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  • 2401.
    Zhan, Shaoqi
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Triviño, Juan Angel De Gracia
    Ahlquist, Mårten S. G.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    The Carboxylate Ligand as an Oxide Relay in Catalytic Water Oxidation.In: Article in journal (Other academic)
    Abstract [en]

    Carboxylate groups have diverse functionality in ligands of transiton metal catalysts. Here we present a conceptuallydifferent function of the carboxylates – the oxide relay. It functions by providing an intramolecular nucleophilic oxygen close tothe oxo group to facilitate O-O bond formation, and at a later stage a remote electrophilic center to facilitate OH- nucleophilic attack.EVB-MD models were generated for key bond forming steps, diffusion coefficients and binding free energies from potentialof mean force estimations were calculated from MD simulations, activation free energies of chemical steps were calculated usingdensity functional theory. The catalyst studied is the extremely active Ru(tda)(py)2 water oxidation catalyst. The combination ofsimulation methods allowed for estimation of the turnover frequencies, which were within one order of magnitude from the experimentalresults at different pH values. From the calculated reaction rates we find that at low pH the OH- anion nucleophilic attack isthe rate-limiting step, which changes at high pH to the O-O bond formation step. Both steps are extremely rapid and key to theefficiency is the oxide relay functionality of a pendant carboxylate group. The functionality was discovered for a ruthenium catalyst,but since there is nothing in the mechanism restricting it to this metal, the oxide relay functionality could open new ways todesign the next generation water oxidation catalysts with improved activity.

  • 2402.
    Zhan, Shaoqi
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Zou, Rongfeng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Ahlquist, Mårten S. G.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Dynamics with Explicit Solvation Reveals Formation of the Prereactive Dimer as Sole Determining Factor for the Efficiency of Ru(bda)L-2 Catalysts2018In: ACS Catalysis, ISSN 2155-5435, E-ISSN 2155-5435, Vol. 8, no 9, p. 8642-8648Article in journal (Refereed)
    Abstract [en]

    This report describes all key steps in the O-O bond formation from two separated [Ru-V=O(bda)L-2](+) cations to form the dinuclear [(bda)L2RuIV-O-Ru-IV(bda)L-2](2+) in explicit solvent. The three steps involve the diffusion of the catalysts in the water phase, formation of the prereactive dimer, and the bond formation between the two catalysts. On the basis of the calculated parameters, we compute the rate constant of two catalysts with different L-ligands, isoquinoline and picoline, and the computed values are in excellent agreement with the experimental ones. The interaction of the axial ligands is key to the improved rates of the larger ligand, mainly by facilitating the formation of the prereactive dimer from the solvated monomer. By comparing the binding free energy of hydrophilic Ru-IV-OH and hydrophobic Ru-V=O, the hydrophobic driving force of Ru-V=O in this system has been estimated to 1 kcal mol(-1).

  • 2403.
    Zhang, Biaobiao
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Li, Yuanyuan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Valvo, M.
    Fan, Lizhou
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Daniel, Quentin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Zhang, Peili
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Wang, Linqin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Electrocatalytic Water Oxidation Promoted by 3 D Nanoarchitectured Turbostratic Δ-MnOx on Carbon Nanotubes2017In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 10, no 22, p. 4472-4478Article in journal (Refereed)
    Abstract [en]

    The development of manganese-based water oxidation electrocatalysts is desirable for the production of solar fuels, as manganese is earth-abundant, inexpensive, non-toxic, and has been employed by the Photosystem II in nature for a billion years. Herein, we directly constructed a 3 D nanoarchitectured turbostratic δ-MnOx on carbon nanotube-modified nickel foam (MnOx/CNT/NF) by electrodeposition and a subsequent annealing process. The MnOx/CNT/NF electrode gives a benchmark catalytic current density (10 mA cm−2) at an overpotential (η) of 270 mV under alkaline conditions. A steady current density of 19 mA cm−2 is obtained during electrolysis at 1.53 V for 1.0 h. To the best of our knowledge, this work represents the most efficient manganese-oxide-based water oxidation electrode and demonstrates that manganese oxides, as a structural and functional model of oxygen-evolving complex (OEC) in Photosystem II, can also become comparable to those of most Ni- and Co-based catalysts.

  • 2404.
    Zhang, Biaobiao
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. Dalian Univ Technol.
    Across the Board: Licheng Sun on the Mechanism of O-O Bond Formation in Photosystem II2019In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 12, no 14, p. 3401-3404Article in journal (Refereed)
    Abstract [en]

    In this series of articles, the board members of ChemSusChem discuss recent research articles that they consider of exceptional quality and importance for sustainability. This entry features Prof. L. Sun, who proposes a special mechanism for O-O bond formation in photosystem II with involvement of an Mn-VII-oxo species induced by charge- and structural rearrangements. In this viewpoint, Proton transfer is involved in changes of the first coordination spheres around the Mn-VII-oxo site on the dangling Mn4 with de- and re-coordination of carboxylates (Glu333 and Asp170).

  • 2405.
    Zhang, Biaobiao
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Artificial photosynthesis: opportunities and challenges of molecular catalysts2019In: Chemical Society Reviews, ISSN 0306-0012, E-ISSN 1460-4744, Vol. 48, no 7, p. 2216-2264Article, review/survey (Refereed)
    Abstract [en]

    Molecular catalysis plays an essential role in both natural and artificial photosynthesis (AP). However, the field of molecular catalysis for AP has gradually declined in recent years because of doubt about the long-term stability of molecular-catalyst-based devices. This review summarizes the development history of molecular-catalyst-based AP, including the fundamentals of AP, molecular catalysts for water oxidation, proton reduction and CO2 reduction, and molecular-catalyst-based AP devices, and it provides an analysis of the advantages, challenges, and stability of molecular catalysts. With this review, we aim to highlight the following points: (i) an investigation on molecular catalysis is one of the most promising ways to obtain atom-efficient catalysts with outstanding intrinsic activities; (ii) effective heterogenization of molecular catalysts is currently the primary challenge for the application of molecular catalysis in AP devices; (iii) development of molecular catalysts is a promising way to solve the problems of catalysis involved in practical solar fuel production. In molecular-catalysis-based AP, much has been attained, but more challenges remain with regard to long-term stability and heterogenization techniques.

  • 2406.
    Zhang, Biaobiao
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Ru-bda: Unique Molecular Water-Oxidation Catalysts with Distortion Induced Open Site and Negatively Charged Ligands2019In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 141, no 14, p. 5565-5580Article, review/survey (Refereed)
    Abstract [en]

    A water-oxidation catalyst with high intrinsic activity is the foundation for developing any type of water-splitting device. To celebrate its 10 years anniversary, in this Perspective we focus on the state-of-the-art molecular water-oxidation catalysts (MWOCs), the Ru-bda series (bda = 2,2'-bipyridine-6,6'-dicarboxylate), to offer strategies for the design and synthesis of more advanced MWOCs. The O-O bond formation mechanisms, derivatives, applications, and reasons behind the outstanding catalytic activities of Ru-bda catalysts are summarized and discussed. The excellent performance of the Ru-bda catalyst is owing to its unique structural features: the distortion induced 7-coordination and the carboxylate ligands with coordination flexibility, proton transfer function as well as small steric hindrance. Inspired by the Ru-bda catalysts, we emphasize that the introduction of negatively charged groups, such as the carboxylate group, into ligands is an effective strategy to lower the onset potential of MWOCs. Moreover, distortion of the regular configuration of a transition metal complex by ligand design to generate a wide open site as the catalytic site for binding the substrate as an extra-coordination is proposed as a new concept for the design of efficient molecular catalysts. These inspirations can be expected to play a great role in not only water oxidation catalysis but also other small molecule activation and conversion reactions involving artificial photosynthesis, such as CO2 reduction and N-2 fixation reactions.

  • 2407.
    Zhang, Biaobiao
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Why nature chose the Mn4CaO5 cluster as water-splitting catalyst in photosystem II: a new hypothesis for the mechanism of O-O bond formation2018In: Dalton Transactions, ISSN 1477-9226, E-ISSN 1477-9234, Vol. 47, no 41, p. 14381-14387Article, review/survey (Refereed)
    Abstract [en]

    Resolving the questions, namely, the selection of Mn by nature to build the oxygen-evolving complex (OEC) and the presence of a cubic Mn3CaO4 structure in OEC coupled with an additional dangling Mn (Mn4) via mu-O atom are not only important to uncover the secret of water oxidation in nature, but also essential to achieve a blueprint for developing advanced water-oxidation catalysts for artificial photosynthesis. Based on the important experimental results reported so far in the literature and on our own findings, we propose a new hypothesis for the water oxidation mechanism in OEC. In this new hypothesis, we propose for the first time, a complete catalytic cycle involving a charge-rearrangement-induced Mn-VII-dioxo species on the dangling Mn4 during the S-3 -> S-4 transition. Moreover, the O-O bond is formed within this Mn-VII-dioxo site, which is totally different from that discussed in other existing proposals.

  • 2408.
    Zhang, Bo
    et al.
    Dalian Univ Technol, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Hou, Jungang
    Dalian Univ Technol, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Wu, Yunzhen
    Dalian Univ Technol, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Cao, Shuyan
    Dalian Univ Technol, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Li, Zhuwei
    Dalian Univ Technol, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Nie, Xiaowa
    Dalian Univ Technol, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Gao, Zhanming
    Dalian Univ Technol, Inst Energy Sci & Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. Dalian Univ Technol, Inst Energy Sci & Technol, DUT .
    Tailoring Active Sites in Mesoporous Defect-Rich NC/V-o-WON Heterostructure Array for Superior Electrocatalytic Hydrogen Evolution2019In: ADVANCED ENERGY MATERIALS, ISSN 1614-6832, Vol. 9, no 12, article id 1803693Article in journal (Refereed)
    Abstract [en]

    Tailoring active sites in earth-abundant non-noble metal electrocatalysts are required toward widespread applications in sustainable energy fields. Herein, an integrated mesoporous heterostructure array is reported by a hydrogenation/nitridation-induced in situ growth strategy. Highly conductive oxygen-vacancies-rich tungsten oxynitride (V-o-WON) nanorod array acts as the backbone encapsulated by ultrathin nitrogen-doped carbon (NC) nanolayers, forming high-quality shell/core NC/V-o-WON heterostructures. Density functional theory calculations reveal that defect-rich heterostructure arrays not only enhance the conductivity and modulate electronic structure but also promote the adsorption and dissociation of reactants and offer substantial potential sites. As expected, porous NC/V-o-WON array exhibits a small overpotential of 16 mV at the current density of 10 mA cm(-2) and a low Tafel slope of 33 mV per decade in alkaline media, accompanied by negligible loss upon a large current density over 100 h. Benefiting from outstanding electrocatalytic hydrogen evolution reaction performance and stability, this defective heterostructure could serve as a prominent alternative electrocatalyst for renewable energy applications.

  • 2409.
    Zhang, Cevin
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Baalsrud Hauge, Jannicke
    KTH, School of Industrial Engineering and Management (ITM).
    Pukk Härenstam, Karin
    Meijer, Sebastiaan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    A Serious Logistical Game of Paediatric Emergency Medicine: Proposed Scoring Mechanism and Pilot Test2019In: Games and Learning Alliance, 8th International Conference, GALA 2019, Athens, Greece, November 27–29, 2019, Proceedings / [ed] Antonios LiapisGeorgios N. YannakakisManuel GentileManuel Ninaus, Springer Publishing Company, 2019, p. 468-478Chapter in book (Refereed)
    Abstract [en]

    Outcomes of care for various diseases and urgent conditions in an emergency department are dependent on balancing the patient’s need and available resources through management and coordination under often rapidly changing preconditions. However, although it is central to resilient operations, decision-making in dynamic resource management is rarely visible to managers. Sometimes the identification of successful strategies is apparent only through adverse event reports. A simulation game could be helpful for the acquisition of non-technical skills in addressing operational conundrums that could threaten the defence ability of a paediatric emergency department under care production pressures. This contribution presents a Sandtable serious logistical game of the care production system and, in particular, proposes its scoring mechanism, which was tested in a set of logistical experiments. The results show that through gamification, participants were challenged in terms of their intrinsic self-interest when it came to approaching the work. More importantly, the proposed extrinsic reward system allows all parallel functional roles to be equally rewarded as the game evolves. Anticipatory human resource management is identified as a successful strategy for achieving a sustainable working environment if the organizational resilience is confronted with patient inflow surges during the busiest hours of the busiest day.

  • 2410.
    Zhang, Cevin
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Sebastiaan, Meijer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    A Simulation Game of Patient Transportation2019In: Neo-Simulation and Gaming Toward Active Learning / [ed] Ryoju Hamada;Songsri Soranastaporn; Hidehiko Kanegae; Pongchai Dumrongrojwatthana; Settachai Chaisanit; Paola Rizzi; Vinod Dumblekar, Springer, 2019, 1, p. 53-66Chapter in book (Refereed)
    Abstract [en]

    The handling of patients is a complex process. The training and education of patient transportation workers are meant to ensure efficiency and health outcomes. A simulation game, joined by personnel with working experience or prospective professionals in the healthcare system, is a life-like medium for improving decision makings in non-rational operation management. However, few examples are known in regard to synthesizing complex systems, such as clinical facilities, into healthcare simulation games. In order to fill this gap, this work proposes the adopt theory and reports the development of a simulation game that reconciles patient handling with the support of different types of simulation techniques. The simulation game has a physical entity simulator as its back-end and a panel of command and control for each player as its front end. The physical entity simulator is based on the interactions of mobile agents. Agent-based modeling targets the correct level of representation of the operative environment. The simulation game is tested with managers who have more than 10-years of working experience with patient flow management in pediatric care. Reflections from players indicate that modeling and abstraction using an agent model is an efficient synthesis of complex systems. The theory, methods, and results of this study are expected to contribute to the development of simulation games that can be applied in health service provision, in general, and in patient transportation, in particular.

  • 2411.
    Zhang, Chen
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Grandits, Thomas
    KTH, School of Technology and Health (STH).
    Härenstam, Karin
    Karolinska Institutet.
    Hauge, Jannicke
    KTH, School of Industrial Engineering and Management (ITM).
    Meijer, Sebastiaan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    A systematic literature review of simulation models for non-technical skill training in healthcare logistics2018In: Advances in Simulation, ISSN 2059-0628, p. 1-15Article in journal (Refereed)
    Abstract [en]

    Resource allocation in patient care relies heavily on individual judgements of healthcare professionals. Such professionals perform coordinating functions by managing the timing and execution of a multitude of care processes for multiple patients. Based on advances in simulation, new technologies that could be used for establishing realistic representations have been developed. These simulations can be used to facilitate understanding of various situations, coordination training and education in logistics, decision-making processes, and design aspects of the healthcare system. However, no study in the literature has synthesized the types of simulations models available for non-technical skills training and coordination of care. A systematic literature review, following the PRISMA guidelines, was performed to identify simulation models that could be used for training individuals in operative logistical coordination that occurs on a daily basis. This article reviewed papers of simulation in healthcare logistics presented in the Web of Science Core Collections, ACM digital library, and JSTOR databases. We conducted a screening process to gather relevant papers as the knowledge foundation of our literature study. The screening process involved a query-based identification of papers and an assessment of relevance and quality. Two hundred ninety-four papers met the inclusion criteria. The review showed that different types of simulation models can be used for constructing scenarios for addressing different types of problems, primarily for training and education sessions. The papers identified were classified according to their utilized paradigm and focus areas. (1) Discrete-event simulation in single-category and single-unit scenarios formed the most dominant approach to developing healthcare simulations and dominated all other categories by a large margin. (2) As we approached a systems perspective (cross-departmental and cross-institutional), discrete-event simulation became less popular and is complemented by system dynamics or hybrid modeling. (3) Agent-based simulations and participatory simulations have increased in absolute terms, but the share of these modeling techniques among all simulations in this field remains low. An extensive study analyzing the literature on simulation in healthcare logistics indicates a growth in the number of examples demonstrating how simulation can be used in healthcare settings. Results show that the majority of studies create situations in which non-technical skills of managers, coordinators, and decision makers can be trained. However, more system-level and complex system-based approaches are limited and use methods other than discrete-event simulation.

  • 2412.
    Zhang, Cheng
    et al.
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Bidkhori, Gholamreza
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Benfeitas, Rui
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Lee, Sunjae
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Arif, Muhammad
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Systems Biology.
    Uhlen, Mathias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Systems Biology.
    Mardinoglu, Adil
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    ESS: A Tool for Genome-Scale Quantification of Essentiality Score for Reaction/Genes in Constraint-Based Modeling2018In: Frontiers in Physiology, ISSN 1664-042X, E-ISSN 1664-042X, Vol. 9, article id 1355Article in journal (Refereed)
    Abstract [en]

    Genome-scale metabolic models (GEMs) are comprehensive descriptions of cell metabolism and have been extensively used to understand biological responses in health and disease. One such application is in determining metabolic adaptation to the absence of a gene or reaction, i.e., essentiality analysis. However, current methods do not permit efficiently and accurately quantifying reaction/gene essentiality. Here, we present Essentiality Score Simulator (ESS), a tool for quantification of gene/reaction essentialities in GEMs. ESS quantifies and scores essentiality of each reaction/gene and their combinations based on the stoichiometric balance using synthetic lethal analysis. This method provides an option to weight metabolic models which currently rely mostly on topologic parameters, and is potentially useful to investigate the metabolic pathway differences between different organisms, cells, tissues, and/or diseases. We benchmarked the proposed method against multiple network topology parameters, and observed that our method displayed higher accuracy based on experimental evidence. In addition, we demonstrated its application in the wild-type and ldh knock-out E. coli core model, as well as two human cell lines, and revealed the changes of essentiality in metabolic pathways based on the reactions essentiality score. ESS is available without any limitation at https://sourceforge.net/projects/essentiality-score-simulator.

  • 2413.
    Zhang, Chi
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Sustainable Business Innovation of Photovoltaic Water Pumping Systems2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The development of renewable energy technology provides an effective approach to replace fossil fuels for greenhouse gas (GHG) emission. Technological innovation and transfer are the main driving forces in promoting renewable energy usage, because of the better efficiency and economic payback under an emission reduction target. With three of the mechanisms of emission trading originating from the Kyoto Protocol, the most wildly accepted and important mechanism between developed and developing countries is the Clean Development Mechanism (CDM). The CDM has been implemented contributing the most of the trading carbon credits. In this study, by extracting and building an exclusive database of issued Chinese CDM projects, a modified multivariable logistic regression model for technology transfer’s correlation test with 11 extended indicators was investigated for the first time. Renewable energy projects were analyzed with certified emission reduction (CER) sizes, economic development, and geographic scopes.In addition, technological innovation should also be enhanced with new business developments to demonstrate and scale up technologies for better economic and environmental performances. This doctoral thesis studied photovoltaic water pumping (PVWP) technology as a technological solution for integration with the new business model for development and co-benefits. The integration of PVWP with water saving irrigation techniques and sustainable management of water resources, leads to technical innovations, economic benefits, and climate benefits. Field measurements at a pilot PVWP system in Inner Mongolia were conducted with detailed economic performance analyses. Different scenarios for PVWP systems considering variant market incentives were proposed with internal rate of return (IRR), and discounted payback period analyses to develop a new business model approach for implementing PVWP systems with multi-value propositions. The environmental externalities were successfully addressed by evaluating the CO2 emission reduction credits. The economic assessment of feasible and optimal production processes for implementing PVWP systems in dairy milk production was conducted with self-supplied energy and forage assumptions. In comparison with other financing mechanisms, discrete choice model analyses were employed with interviews and costumer behavior surveys to explore the willingness to purchase through crowd funding mechanisms in financing integrated PVWP systems.The results showed that emission reduction mechanisms, such as CDM, have promoted the renewable energy development in China with the national incentives at an entrance level. Yet, the limited sizes and lower income from CERs of renewable energy projects than other projects, required renewable energy projects to develop more advanced technological innovations and business model innovations.  The PVWP systems represent the better technical and economic solutions under a feasible innovated business model in comparison with traditional photovoltaic (PV) systems and current PV business models. The dairy farms with integrated PVWP systems and self-sufficient feeds could improve their investment performance through extra energy saving and CO2 emission reductions. The semi-structured interviews and customer surveys’ results showed that customers can tolerate high prices, and are willing to crowd-fund nutritious and secure cow milk with environmental compensation characters. The results from the PVWP technology integration in China as a specific PV application study can be further applied for the business model of innovation of renewable energy systems in other regions of the world under emission reduction targets leading to economic and environmental benefits.

  • 2414.
    Zhang, Chi
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Sch Business Soc & Engn, SE-72123 Vasteras, Sweden..
    Yang, Jin
    China Univ Geosci, Sch Humanities & Econ Management, Beijing 100083, Peoples R China..
    Yu, Chaoqing
    Tsinghua Univ, Dept Earth Syst Sci, Beijing 100084, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Sch Business Soc & Engn, SE-72123 Vasteras, Sweden..
    Economic assessment of photovoltaic water pumping integration with dairy milk production2018In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 177, p. 750-764Article in journal (Refereed)
    Abstract [en]

    As dairy consumption grows, domestic dairy farms face challenges in reducing the cost of feeds and the production of high-quality milk for market demands. This paper aims to introduce and integrate solar energy into the milk production chain to investigate its economic performance. By collecting data on milk production processes from 11 dairy farms in China, we quantified electricity usage and costs of milk production to identify the best and worst cases. Crop yields response to the water demand and the electricity requirements of the dairy farms were considered. The study simulated scenarios of self-sufficiency at 20%, 80%, and 100%, in the identified farms by integrating a photovoltaic water pumping (PVWP) system to provide both power and water for alfalfa and other feeds' irrigation and subsequent milk production. We evaluated annual discounted cost, revenue and net profit under each scenario and case. The results showed that a dairy farm with an integrated PVWP system and self-sufficient feeds would lead to value add-ins, such as electricity saving with solar energy generation, economic cost saving of crops, and CO2 emission reduction. The analysis on return on investment (ROI) and internal rate of return (IRR) revealed that not all the self-sufficient feeds can bring positive marginal profit. Among the investigated scenarios and cases, the dairy farm marked out by the highest ROI with 3.12 and IRR with 20.4%, was the farm where the integrated PVWP system was used to reach 20% self-sufficiency (self-production of only alfalfa). The other scenarios and cases with higher levels of self-sufficiency showed lower ROIs and IRRs. This indicates that high self-production levels of feeds decrease the total profit due to high investment cost. Sensitivity analyses of crop price and operational cost were conducted for ROI with single and double factor approaches. Scale and production of feeds proportions should be carefully considered in improving the economic performance of dairy milk production.

  • 2415.
    Zhang, Chi
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Campana, Pietro Elia
    Yang, Jin
    Yu, Chaoqing
    Yan, Jinyue
    KTH.
    Economic Assessment of Photovoltaic Water Pumping Integration with Dairy Milk ProductionManuscript (preprint) (Other academic)
    Abstract [en]

    As dairy consumption grows, domestic dairy farms face challenges in reducing the cost of feeds and the production of high-quality milk for market demands. This paper aims to introduce and integrate solar energy into the milk production chain to investigate its economic performance. By collecting data on milk production processes from 11 dairy farms in China, we quantified electricity usage and costs of milk production to identify the best and worst cases. Crop yields response to the water demand and the electricity requirements of the dairy farms were considered. The study simulated scenarios of self-sufficiency at 20%, 80%, and 100%, in the identified farms by integrating a photovoltaic water pumping (PVWP) system to provide both power and water for alfalfa and other feeds’ irrigation and subsequent milk production. We evaluated annual discounted cost, revenue and net profit under each scenario and case. The results showed that a dairy farm with an integrated PVWP system and self-sufficient feeds would lead to value add-ins, such as electricity saving with solar energy generation, economic cost saving of crops, and CO2 emission reduction. The analysis on return on investment (ROI) and internal rate of return (IRR) revealed that not all the self-sufficient feeds can bring positive marginal profit. Among the investigated scenarios and cases, the dairy farm marked out by the highest ROI with 3.12 and IRR with 20.4%, was the farm where the integrated PVWP system was used to reach 20% self-sufficiency (self-production of only alfalfa). The other scenarios and cases with higher levels of self-sufficiency showed lower ROIs and IRRs. This indicates that high self-production levels of feeds decrease the total profit due to high investment cost. Sensitivity analyses of crop price and operational cost were conducted for ROI with single and double factor approaches. Scale and production of feeds proportions should be carefully considered in improving the economic performance of dairy milk production. 

  • 2416.
    Zhang, Chi
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Gong, Peng
    Tsinghua Univ, Dept Earth Syst Sci, Ctr Hlth Cities, Inst China Sustainable Urbanizat, Beijing 100084, Peoples R China.;Tsinghua Univ, Tsinghua Urban Inst, Beijing 100084, Peoples R China..
    Healthy China: from words to actions2019In: LANCET PUBLIC HEALTH, ISSN 2468-2667, Vol. 4, no 9, p. E438-E439Article in journal (Other academic)
  • 2417.
    Zhang, Chuang
    et al.
    Beijing Univ Posts & Telecommun, Pattern Recognit & Intelligent Syst Lab, Beijing 100876, Peoples R China..
    Wu, Ming
    Beijing Univ Posts & Telecommun, Pattern Recognit & Intelligent Syst Lab, Beijing 100876, Peoples R China..
    Chen, Jinyu
    Beijing Univ Posts & Telecommun, Pattern Recognit & Intelligent Syst Lab, Beijing 100876, Peoples R China..
    Chen, Kaiyan
    Beijing Univ Posts & Telecommun, Pattern Recognit & Intelligent Syst Lab, Beijing 100876, Peoples R China..
    Zhang, Chi
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Xie, Chao
    Natl Meteorol Ctr, Beijing 100081, Peoples R China..
    Huang, Bin
    Natl Meteorol Ctr, Beijing 100081, Peoples R China..
    He, Zichen
    McGill Univ, Dept Stat & Comp Sci, Montreal, PQ H3A 0G4, Canada..
    Weather Visibility Prediction Based on Multimodal Fusion2019In: IEEE Access, E-ISSN 2169-3536, Vol. 7, p. 74776-74786Article in journal (Refereed)
    Abstract [en]

    Visibility affects all forms of traffic: roads, sailing, and aviation. Visibility prediction is meaningful in guiding production and life. Different from weather prediction, which relies solely on atmosphere factors, the factors that affect meteorological visibility are more complicated, such as the air pollution caused by factory exhaust emission. However, the current prediction of visibility is mostly based on the numerical prediction method similar to the weather prediction. We proposed a method using multimodal fusion to build a weather visibility prediction system in this paper. An advanced numerical prediction model and a method for emission detection were used to build a multimodal fusion visibility prediction system. We used the most advanced regression algorithm, XGBoost, and LightGBM, to train the fusion model for numerical prediction. Through the estimation of factory emission by the traditional detector in the satellite image, we propose to add the result of estimation based on Landsat-8 satellite images to assist the prediction. By testing our numerical model in atmosphere data of various meteorological observation stations in Beijing-Tianjin-Hebei region from 2002 to 2018, our numerical prediction model turns out to be more accurate than other existing methods, and after fusing with emission detection method, the accuracy of our visibility prediction system has been further improved.

  • 2418.
    Zhang, Fan
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Chen, Chengdong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Hou, R.
    Li, Jing
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Cao, Yanhui
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Dong, S.
    Lin, C.
    Pan, Jinshan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Investigation and application of mussel adhesive protein nanocomposite film-forming inhibitor for reinforced concrete engineering2019In: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 153, p. 333-340Article in journal (Refereed)
    Abstract [en]

    A mussel adhesive protein based nanocomposite thin film was produced to be applied as surface pre-treatment or primer on rebars of reinforced concrete. The film deposition and drying processes were investigated to enhance the corrosion protection, and facilitate large-scale industrial applications. The morphology, chemical composition and microstructure of the film were characterised with SEM, EDS, Micro-IR and AFM techniques. EIS results suggested the film provides excellent and increased corrosion protection for the carbon steel in mild and extreme concrete pore solutions. In-situ AFM results demonstrated the self-healing ability of the film to the pitting corrosion.

  • 2419.
    Zhang, Fan
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Pan, Jinshan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Recent Development of Corrosion Protection Strategy Based on Mussel Adhesive Protein2019In: FRONTIERS IN MATERIALS, ISSN 2296-8016, Vol. 6, article id 207Article, review/survey (Refereed)
    Abstract [en]

    Many of traditional anti-corrosion approaches using chromate are effective but hazardous to natural environment and human health, so development of green and effective alternatives is desirable. One of the mussel adhesive proteins derived from mussel byssus presents extraordinary adhesion to steel surface and exhibits film-forming and corrosion inhibition properties. Novel strategies for enhancing the corrosion inhibition of steel by the protein have been demonstrated recently. The protein together with ceria nanoparticles presents a great potential for the development of new corrosion inhibitors and thin films that are "green" and "effective," and have "smart" protection properties.

  • 2420.
    Zhang, Fuguo
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Cong, Jiayan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Li, Yuanyuan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Bergstrand, Jan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Liu, Haichun
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Cai, Bin
    State Key Laboratory of Fine Chemicals, Dalian University of Technology (DUT).
    Hajian, Alireza
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Yao, Zhaoyang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Wang, Linqin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Hao, Yan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Yang, Xichuan
    State Key Laboratory of Fine Chemicals, Dalian University of Technology (DUT).
    Gardner, James M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Ågren, Hans
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Widengren, Jerker
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Kloo, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. State Key Laboratory of Fine Chemicals, Dalian University of Technology (DUT).
    A facile route to grain morphology controllable perovskite thin films towards highly efficient perovskite solar cells2018In: Nano Energy, ISSN 2211-2855, E-ISSN 2211-3282, Vol. 53, p. 405-414Article in journal (Refereed)
    Abstract [en]

    Perovskite photovoltaics have recently attracted extensive attention due to their unprecedented high power conversion efficiencies (PCEs) in combination with primitive manufacturing conditions. However, the inherent polycrystalline nature of perovskite films renders an exceptional density of structural defects, especially at the grain boundaries (GBs) and film surfaces, representing a key challenge that impedes the further performance improvement of perovskite solar cells (PSCs) and large solar module ambitions towards commercialization. Here, a novel strategy is presented utilizing a simple ethylammonium chloride (EACl) additive in combination with a facile solvent bathing approach to achieve high quality methyammonium lead iodide (MAPbI3) films. Well-oriented, micron-sized grains were observed, which contribute to an extended carrier lifetime and reduced trap density. Further investigations unraveled the distinctively prominent effects of EACl in modulating the perovskite film quality. The EACl was found to promote the perovskite grain growing without undergoing the formation of intermediate phases. Moreover, the EACl was also revealed to deplete at relative low temperature to enhance the film quality without compromising the beneficial bandgap for solar cell applications. This new strategy boosts the power conversion efficiency (PCE) to 20.9% and 19.0% for devices with effective areas of 0.126 cm2 and 1.020 cm2, respectively, with negligible current hysteresis and enhanced stability. Besides, perovskite films with a size of 10 × 10 cm2, and an assembled 16 cm2(5 × 5 cm2 module) perovskite solar module with a PCE of over 11% were constructed.

  • 2421.
    Zhang, Hongtao
    et al.
    Univ Waterloo, Dept Mech & Mechatron Engn, Lab Fuel Cell & Green Energy RD&D 20 20, Waterloo, ON N2L 3G1, Canada.;Univ Waterloo, Dept Appl Math, Waterloo, ON N2L 3G1, Canada..
    Li, Xianguo
    Univ Waterloo, Dept Mech & Mechatron Engn, Lab Fuel Cell & Green Energy RD&D 20 20, Waterloo, ON N2L 3G1, Canada..
    Liu, Xinzhi
    Univ Waterloo, Dept Appl Math, Waterloo, ON N2L 3G1, Canada..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Sch Sustainable Dev Soc & Technol, S-72123 Vasteras, Sweden..
    Enhancing fuel cell durability for fuel cell plug-in hybrid electric vehicles through strategic power management2019In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 241, p. 483-490Article in journal (Refereed)
    Abstract [en]

    Fuel cell plug-in hybrid electric vehicles (FC-PHEVs) can have extended range while utilizing cheap grid electricity, but has poor durability of onboard fuel cells due to dynamic loading. In this study, fuel cell durability is enhanced significantly for a novel configuration of FC-PHEVs with three fuel cell stacks through strategic power management by making each fuel cell stack work only at a fixed operating point (i.e., constant output power) and by shortening its active time (operation) via on-off switching control. A hysteresis control strategy of power management is designed to make the active time evenly distributed over the three fuel cell stacks and to reduce the number of on-off switching. The results indicate that the durability of the onboard fuel cells can be increased 11.8, 4.8 and 6.9 times, respectively, for an urban, highway and a combined urban-highway driving cycle. This enhanced fuel cell durability is derived from the fact that the average power demand of real-time driving cycles is only a fraction of the maximum power that FC-PHEVs could provide, and substantially increased durability can be used to reduce the over-design, hence the cost, of fuel cells.

  • 2422. Zhang, J.
    et al.
    Natarajan Arul, Murugan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Tian, Y.
    Bertagnin, C.
    Fang, Z.
    Kang, D.
    Kong, X.
    Jia, H.
    Sun, Z.
    Jia, R.
    Gao, P.
    Poongavanam, V.
    Loregian, A.
    Xu, W.
    Ma, X.
    Ding, X.
    Huang, B.
    Zhan, P.
    Liu, X.
    Structure-Based Optimization of N-Substituted Oseltamivir Derivatives as Potent Anti-Influenza A Virus Agents with Significantly Improved Potency against Oseltamivir-Resistant N1-H274Y Variant2018In: Journal of Medicinal Chemistry, ISSN 0022-2623, E-ISSN 1520-4804, Vol. 61, no 22, p. 9976-9999Article in journal (Refereed)
    Abstract [en]

    Due to the emergence of highly pathogenic and oseltamivir-resistant influenza viruses, there is an urgent need to develop new anti-influenza agents. Herein, five subseries of oseltamivir derivatives were designed and synthesized to improve their activity toward drug-resistant viral strains by further exploiting the 150-cavity in the neuraminidases (NAs). The bioassay results showed that compound 21h exhibited antiviral activities similar to or better than those of oseltamivir carboxylate (OSC) against H5N1, H5N2, H5N6, and H5N8. Besides, 21h was 5- to 86-fold more potent than OSC toward N1, N8, and N1-H274Y mutant NAs in the inhibitory assays. Computational studies provided a plausible rationale for the high potency of 21h against group-1 and N1-H274Y NAs. In addition, 21h demonstrated acceptable oral bioavailability, low acute toxicity, potent antiviral activity in vivo, and high metabolic stability. Overall, the above excellent profiles make 21h a promising drug candidate for the treatment of influenza virus infection.

  • 2423.
    Zhang, Jinbao
    et al.
    Monash Univ, Dept Mat Sci & Engn, Clayton, Vic 3800, Australia..
    Daniel, Quentin
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Zhang, Tian
    Monash Univ, Dept Mat Sci & Engn, Clayton, Vic 3800, Australia..
    Wen, Xiaoming
    Swinburne Univ Technol, Ctr Microphoton, Melbourne, Vic 3122, Australia..
    Xu, Bo
    Uppsala Univ, Phys Chem, Dept Chem, Angstrom Lab, Box 523, S-75120 Uppsala, Sweden..
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. Dalian Univ Technol, State Key Lab Fine Chem, DUT KTH Joint Educ & Res Ctr Mol Devices, Dalian 116012, Peoples R China..
    Bach, Udo
    Monash Univ, Dept Chem Engn, Clayton, Vic 3800, Australia.;CSIRO Mfg, Clayton, Vic 3168, Australia.;Melbourne Ctr Nanofabricat, Clayton, Vic 3800, Australia..
    Cheng, Yi-Bing
    Monash Univ, Dept Mat Sci & Engn, Clayton, Vic 3800, Australia.;Wuhan Univ Technol, State Key Lab Silicate Mat Architectures, Wuhan 430070, Hubei, Peoples R China..
    Chemical Dopant Engineering in Hole Transport Layers for Efficient Perovskite Solar Cells: Insight into the Interfacial Recombination2018In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 12, no 10, p. 10452-10462Article in journal (Refereed)
    Abstract [en]

    Chemical doping of organic semiconductors has been recognized as an effective way to enhance the electrical conductivity. In perovskite solar cells (PSCs), various types of dopants have been developed for organic hole transport materials (HTMs); however, the knowledge of the basic requirements for being efficient dopants as well as the comprehensive roles of the dopants in PSCs has not been clearly revealed. Here, three copper-based complexes with controlled redox activities are applied as dopants in PSCs, and it is found that the oxidative reactivity of dopants presents substantial impacts on conductivity, charge dynamics, and solar cell performance. A significant improvement of open- circuit voltage (V-oc) by more than 100 mV and an increase of power conversion efficiency from 13.2 to 19.3% have been achieved by tuning the doping level of the HTM. The observed large variation of V-oc for three dopants reveals their different recombination kinetics at the perovskite/HTM interfaces and suggests a model of an interfacial recombination mechanism. We also suggest that the dopants in HTMs can also affect the charge recombination kinetics as well as the solar cell performance. Based on these findings, a strategy is proposed to physically passivate the electron- hole recombination by inserting an ultrathin Al2O3 insulating layer between the perovskite and the HTM. This strategy contributes a significant enhancement of the power conversion efficiency and environmental stability, indicating that dopant engineering is one crucial way to further improve the performance of PSCs.

  • 2424.
    Zhang, Li
    et al.
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Yang, Xichuan
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Wang, Weihan
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Gurzadyan, Gagik G.
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Li, Jiajia
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Li, Xiaoxin
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    An, Jincheng
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Yu, Ze
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Wang, Haoxin
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Cai, Bin
    Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China..
    Hagfeldt, Anders
    Ecole Polytech Fed Lausanne, Lab Photomol Sci, Inst Chem Sci & Engn, CH-1015 Lausanne, Switzerland..
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. Dalian Univ Technol, DUT KTH Joint Educ & Res Ctr Mol Devices, Inst Artificial Photosynth, State Key Lab Fine Chem, 2 Linggong Rd, Dalian 116024, Peoples R China.
    13.6% Efficient Organic Dye-Sensitized Solar Cells by Minimizing Energy Losses of the Excited State2019In: ACS ENERGY LETTERS, ISSN 2380-8195, Vol. 4, no 4, p. 943-951Article in journal (Refereed)
    Abstract [en]

    The electron-injection energy losses of dye-sensitized solar cells (DSSCs) are among the fundamental problems hindering their successful breakthrough application. Two triazatruxene (TAT)-based sensitizers, with one containing a flexible Z-type double bond and another a rigid single bond, coded as ZL001 and ZL003, respectively, have been synthesized and applied in DSSCs to probe the energy losses in the process of electron injection. Using time-resolved laser spectroscopic techniques in the kinetic study, ZL003 with the rigid single bond promotes much faster electron injection into the conductive band of TiO2 especially in the locally excited state (hot injection), which leads to higher electron density in TiO2 and a higher V-oc. The devices based on ZL003 exhibited a champion power conversion efficiency (PCE) of 13.6% with V-oc = 956 mV, J(sc) = 20.73 mA cm(-2), and FF = 68.5%, which are among the highest recorded results to date on single dye-sensitized DSSCs. An independent certified PCE of 12.4% has been obtained for devices based on ZL003.

  • 2425.
    Zhang, Liang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology. VINNOVA Competence Ctr Adv Bioprod Continuous Pro, AdBIOPRO, Stockholm, Sweden..
    Castan, Andreas
    GE Healthcare Biosci AB, Bjorkgatan 30, S-75184 Uppsala, Sweden..
    Stevenson, Joanne
    Cobra Biol AB, Stockholm, Sweden..
    Chatzissavidou, Nathalie
    Cobra Biol AB, Stockholm, Sweden..
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience.
    Chotteau, Veronique
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology. VINNOVA Competence Ctr Adv Bioprod Continuous Pro, AdBIOPRO, Stockholm, Sweden..
    Combined effects of glycosylation precursors and lactate on the glycoprofile of IgG produced by CHO cells2019In: Journal of Biotechnology, ISSN 0168-1656, E-ISSN 1873-4863, Vol. 289, p. 71-79Article in journal (Refereed)
    Abstract [en]

    The glycosylation profile of therapeutic monoclonal antibodies (mAbs) is a crucial quality parameter for industrial Immunoglobulin G (IgG) production. Several alternative carbon sources, which function as glycosylation precursors, have been reported to impact the glycosylation pattern. Since the cells give priority to glucose uptake, the presence of this substrate can lower the effects of alternative sugars on the glycosylation. In order to get a better understanding of the influence of alternative sugars on the glycosylation and to investigate how they impact each other, combinations of mannose, fructose, galactose and fucose were fed to Chinese hamster ovary (CHO) cells in batch culture when the glucose became depleted and the lactate, accumulated in the culture, was used as carbon source. Feeding with a feed containing mannose or glucose decreased by 3-7% the percentage of high mannose glycans compared to a feed without mannose or glucose. Feeding with a feed containing galactose led to 8-20% increase of monogalactoglycans (G1) glycans and 2-6% rise of digalactoglycans (G2) glycans compared to feeding without galactose or glucose. The cells fed with fucose exhibited a significantly higher concentration of intracellular GDP-Fucose. This work indicates that a feeding strategy based on non-glucose sugars and potentially lactate, could be adopted to obtain a targeted glycosylation profile.

  • 2426.
    Zhang, Liang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Wang, MingLiang
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligenta system, Decision and Control Systems (Automatic Control).
    Castan, Andreas
    Stevenson, Joanne
    Chatzissavidou, Nathalie
    Hjalmarsson, Håkan
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligenta system, Decision and Control Systems (Automatic Control).
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience.
    Chotteau, Veronique
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology. AdBIOPRO, VINNOVA Competence Centre for Advanced Bioproduction by Continuous Processing, KTH, Sweden.
    Glycan Residues Balance Analysis: A novel model for the N-linked glycosylation of IgG produced by CHO cells.2019In: Metabolic engineering, ISSN 1096-7176, E-ISSN 1096-7184, article id S1096-7176(19)30086-2Article in journal (Refereed)
    Abstract [en]

    The structure of N-linked glycosylation is a very important quality attribute for therapeutic monoclonal antibodies. Different carbon sources in cell culture media, such as mannose and galactose, have been reported to have different influences on the glycosylation patterns. Accurate prediction and control of the glycosylation profile are important for the process development of mammalian cell cultures. In this study, a mathematical model, that we named Glycan Residues Balance Analysis (GReBA), was developed based on the concept of Elementary Flux Mode (EFM), and used to predict the glycosylation profile for steady state cell cultures. Experiments were carried out in pseudo-perfusion cultivation of antibody producing Chinese Hamster Ovary (CHO) cells with various concentrations and combinations of glucose, mannose and galactose. Cultivation of CHO cells with mannose or the combinations of mannose and galactose resulted in decreased lactate and ammonium production, and more matured glycosylation patterns compared to the cultures with glucose. Furthermore, the growth rate and IgG productivity were similar in all the conditions. When the cells were cultured with galactose alone, lactate was fed as well to be used as complementary carbon source, leading to cell growth rate and IgG productivity comparable to feeding the other sugars. The data of the glycoprofiles were used for training the model, and then to simulate the glycosylation changes with varying the concentrations of mannose and galactose. In this study we showed that the GReBA model had a good predictive capacity of the N-linked glycosylation. The GReBA can be used as a guidance for development of glycoprotein cultivation processes.

  • 2427.
    Zhang, Miao
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics. KTH.
    Ngampeerapong, Chonmanart
    Redin, David
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Ahmadian, Afshin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Sychugov, Ilya
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Linnros, Jan
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Thermophoresis-Controlled Size-Dependent DNA Translocation through an Array of Nanopores2018In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 12, no 5, p. 4574-4582Article in journal (Refereed)
    Abstract [en]

    Large arrays of nanopores can be used for high-throughput biomolecule translocation with applications toward size discrimination and sorting at the single-molecule level. In this paper, we propose to discriminate DNA length by the capture rate of the molecules to an array of relatively large nanopores (50–130 nm) by introducing a thermal gradient by laser illumination in front of the pores balancing the force from an external electric field. Nanopore arrays defined by photolithography were batch processed using standard silicon technology in combination with electrochemical etching. Parallel translocation of single, fluorophore-labeled dsDNA strands is recorded by imaging the array with a fast CMOS camera. The experimental data show that the capture rates of DNA molecules decrease with increasing DNA length due to the thermophoretic effect of the molecules. It is shown that the translocation can be completely turned off for the longer molecule using an appropriate bias, thus allowing a size discrimination of the DNA translocation through the nanopores. A derived analytical model correctly predicts the observed capture rate. Our results demonstrate that by combining a thermal and a potential gradient at the nanopores, such large nanopore arrays can potentially be used as a low-cost, high-throughput platform for molecule sensing and sorting.

  • 2428.
    Zhang, Peili
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Li, L.
    Nordlund, D.
    Chen, Hong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Fan, Lizhou
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Zhang, Biaobiao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Sheng, Xia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Daniel, Quentin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Dendritic core-shell nickel-iron-copper metal/metal oxide electrode for efficient electrocatalytic water oxidation2018In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 9, no 1, article id 381Article in journal (Refereed)
    Abstract [en]

    Electrochemical water splitting requires efficient water oxidation catalysts to accelerate the sluggish kinetics of water oxidation reaction. Here, we report a promisingly dendritic core-shell nickel-iron-copper metal/metal oxide electrode, prepared via dealloying with an electrodeposited nickel-iron-copper alloy as a precursor, as the catalyst for water oxidation. The as-prepared core-shell nickel-iron-copper electrode is characterized with porous oxide shells and metallic cores. This tri-metal-based core-shell nickel-iron-copper electrode exhibits a remarkable activity toward water oxidation in alkaline medium with an overpotential of only 180 mV at a current density of 10 mA cm-2. The core-shell NiFeCu electrode exhibits pH-dependent oxygen evolution reaction activity on the reversible hydrogen electrode scale, suggesting that non-concerted proton-electron transfers participate in catalyzing the oxygen evolution reaction. To the best of our knowledge, the as-fabricated core-shell nickel-iron-copper is one of the most promising oxygen evolution catalysts.

  • 2429.
    Zhang, Peili
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, DUT-KTH Joint Education and Research Centre on Molecular Devices, Dalian University of Technology, Dalian, 116024, China.
    Sheng, Xia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, DUT-KTH Joint Education and Research Centre on Molecular Devices, Dalian University of Technology, Dalian, 116024, China.
    Chen, Xiaoyu
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Fang, Zhiyong
    Jiang, Jian
    Wang, Mei
    Li, Fusheng
    Fan, Lizhou
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Ren, Yansong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Zhang, Biaobiao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Timmer, Brian J. J.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Ahlquist, Mårten S. G.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, DUT-KTH Joint Education and Research Centre on Molecular Devices, Dalian University of Technology, Dalian, 116024, China.
    Paired Electrocatalytic Oxygenation and Hydrogenation of Organic Substrates with Water as the Oxygen and Hydrogen Source2019In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 58, no 27, p. 9155-9159Article in journal (Refereed)
    Abstract [en]

    The use of water as an oxygen and hydrogen source for the paired oxygenation and hydrogenation of organic substrates to produce valuable chemicals is of utmost importance as a means of establishing green chemical syntheses. Inspired by the active Ni3+ intermediates involved in electro-catalytic water oxidation by nickel-based materials, we prepared NiBx as a catalyst and used water as the oxygen source for the oxygenation of various organic compounds. NiBx was further employed as both an anode and a cathode in a paired electrosynthesis cell for the respective oxygenation and hydrogenation of organic compounds, with water as both the oxygen and hydrogen source. Conversion efficiency and selectivity of >= 99% were observed during the oxygenation of 5-hydroxy-methylfurfural to 2,5-furandicarboxylic acid and the simultaneous hydrogenation of p-nitrophenol to p-aminophenol. This paired electrosynthesis cell has also been coupled to a solar cell as a stand-alone reactor in response to sunlight.

  • 2430.
    Zhang, Qi
    et al.
    China Univ Petr, Acad Chinese Energy Strategy, Beijing 102249, Peoples R China..
    Li, Hailong
    Malardalen Univ, Sch Business Soc & Engn, Future Energy, Vasteras, Sweden.;Tianjin Univ Commerce, Tianjin Key Lab Refrigerat Technol, Tianjin 300134, Peoples R China..
    Zhu, Lijing
    China Univ Petr, Acad Chinese Energy Strategy, Beijing 102249, Peoples R China..
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Sch Business Soc & Engn, Future Energy, Vasteras, Sweden.
    Lu, Huihui
    China Univ Petr, Acad Chinese Energy Strategy, Beijing 102249, Peoples R China.;Malardalen Univ, Sch Business Soc & Engn, Future Energy, Vasteras, Sweden..
    Wallin, Fredrik
    Malardalen Univ, Sch Business Soc & Engn, Future Energy, Vasteras, Sweden..
    Sun, Qie
    Shandong Univ, Inst Thermal Sci & Technol, Jinan, Shandong, Peoples R China..
    Factors influencing the economics of public charging infrastructures for EV - A review2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 94, p. 500-509Article, review/survey (Refereed)
    Abstract [en]

    Growing concerns about energy conservation and the environmental impacts of greenhouse gas emissions over the world have promoted the development of the electric vehicles (EVs) market. However, one of the biggest barriers in the development of the EV market is the lack of the public charging infrastructure. This paper reviews the factors that can directly and indirectly influence the economics of the public charging infrastructure. The knowledge gaps, barriers and opportunities in the development of the charging infrastructure have been identified and analyzed. In order to promote the development of the public charging infrastructure, more research efforts should be paid on the impacts of psychological factors of customers and the technical development of charging infrastructures and EV batteries. The government support has been proved to play an important role, so that how the government policy can be tailored for the development of the charging infrastructure market should receive more attentions. In addition, the charging price as an endogenous factor should be considered more carefully in modelling the charging infrastructure market. New business models are also urgently needed to accelerate the future development of the public charging infrastructure.

  • 2431.
    Zhang, Qi
    et al.
    East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Key Lab Adv Mat, 130 Meilong Rd, Shanghai 200237, Peoples R China.;East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Joint Int Res Lab Precis Chem & Mol Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China..
    Rao, Si-Jia
    East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Key Lab Adv Mat, 130 Meilong Rd, Shanghai 200237, Peoples R China.;East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Joint Int Res Lab Precis Chem & Mol Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China..
    Xie, Tao
    East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Key Lab Adv Mat, 130 Meilong Rd, Shanghai 200237, Peoples R China.;East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Joint Int Res Lab Precis Chem & Mol Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China..
    Li, Xin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Xu, Tian-Yi
    East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Key Lab Adv Mat, 130 Meilong Rd, Shanghai 200237, Peoples R China.;East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Joint Int Res Lab Precis Chem & Mol Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China..
    Li, Da-Wei
    East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Key Lab Adv Mat, 130 Meilong Rd, Shanghai 200237, Peoples R China.;East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Joint Int Res Lab Precis Chem & Mol Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China..
    Qu, Da-Hui
    East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Key Lab Adv Mat, 130 Meilong Rd, Shanghai 200237, Peoples R China.;East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Joint Int Res Lab Precis Chem & Mol Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China..
    Long, Yi-Tao
    East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Key Lab Adv Mat, 130 Meilong Rd, Shanghai 200237, Peoples R China.;East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Joint Int Res Lab Precis Chem & Mol Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China..
    Tian, He
    East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Key Lab Adv Mat, 130 Meilong Rd, Shanghai 200237, Peoples R China.;East China Univ Sci & Technol, Feringa Nobel Prize Scientist Joint Res Ctr, Sch Chem & Mol Engn, Joint Int Res Lab Precis Chem & Mol Engn, 130 Meilong Rd, Shanghai 200237, Peoples R China..
    Muscle-like Artificial Molecular Actuators for Nanoparticles2018In: CHEM, ISSN 2451-9294, Vol. 4, no 11, p. 2670-2684Article in journal (Refereed)
    Abstract [en]

    Muscle tissue performs crucial contraction/extension motions that generate mechanical force and work by consuming chemical energy. Inspired by this naturally created biomolecular machine, artificial molecular muscles are designed and synthesized to undertake linear actuation functions. However, most of these muscle-like actuators are performed at large ensembles, while to realize the nanoscale actuation at the single-to few-molecule level remains challenging. Herein, we developed an artificial muscle-like molecular actuator that can reversibly control the proximity of the attached nano-objects, gold nanoparticles, within the single-molecule length level by its stimuli-responsive muscle-like linear contraction/extension motion. The molecular actuation motion is accompanied by an optical signal output resulting from the plasmonic resonance properties of gold nanoparticles. Meanwhile, the thermal noise of the muscle-like molecular actuator can be overcome by integrating the optical signal over a sufficiently long period.

  • 2432.
    Zhang, T.
    et al.
    Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden..
    Brumboiu, I. E.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Grazioli, C.
    Sincrotrone Trieste, CNR, ISM, I-34149 Trieste, Basovizza, Italy..
    Guarnaccio, A.
    CNR, ISM, I-85050 Potenza, Italy..
    Coreno, M.
    Sincrotrone Trieste, CNR, ISM, I-34149 Trieste, Basovizza, Italy..
    de Simone, M.
    Sincrotrone Trieste, Lab TASC, CNR, IOM, I-34149 Trieste, Basovizza, Italy..
    Santagata, A.
    CNR, ISM, I-85050 Potenza, Italy..
    Rensmo, H.
    Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden..
    Brena, B.
    Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden..
    Lanzilotto, V.
    Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden..
    Puglia, C.
    Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden..
    Lone-Pair Delocalization Effects within Electron Donor Molecules: The Case of Triphenylamine and Its Thiophene-Analog2018In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 122, no 31, p. 17706-17717Article in journal (Refereed)
    Abstract [en]

    Triphenylamine (TPA) and its thiophene-analog, N,N-diphenyl-2-thiophenamine (DPTA), are both well-known as electron-donating molecules implemented in optoelectronic devices such as organic solar cells and LEDs. Comprehensive valence and core level photoelectron spectroscopy, as well as near edge X-ray absorption spectroscopy (NEXAFS), measurements have been performed on gas phase TPA and DPTA. The experimental results have been compared to density functional theory calculations, providing a detailed description of the molecular electronic structure. Specifically, the C 1s photoelectron lines of both TPA and DPTA were resolved in the different C atom contributions and their binding energies explained as the result of two counter-acting effects: (1) the electronegativity of the nitrogen atom (and sulfur atom in DPTA) and (2) the the N (and S in DPTA) lone-pair electrons. In addition, the C K-edge NEXAFS spectrum of DPTA reveals that the lowest unoccupied molecular orbital (LUMO) energy position is affected differently if the core hole site is on the phenyl compared to the thiophene ring. The electron-donating properties of these two molecules are largely explained by the significant contribution of the N lone-pair electrons (p(z)) to the highest occupied molecular orbital. The contribution to the LUMO and to the empty density of states of the sulfur of the thiophene ring in DPTA explains the better performance of donor-pi-acceptor molecules containing this moiety and implemented in photoenergy conversion devices.

  • 2433.
    Zhang, T.
    et al.
    Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden.;BIT, Sch Informat & Elect, Beijing 100081, Peoples R China..
    Brumboiu, Iulia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology. Korea Adv Inst Sci & Technol, Dept Chem, Daejeon 34141, South Korea..
    Lanzilotto, V.
    Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden.;Univ Roma La Sapienza, Dept Chem, Piazzale Aldo Moro 5, I-00185 Rome, Italy..
    Grazioli, C.
    Sincrotrone Trieste, Lab TASC, CNR, IOM, Trieste, Italy..
    Guarnaccio, A.
    CNR, ISM, Tito, Pz, Italy.;Trieste LD2 Unit, Trieste, Italy..
    Johansson, F. O. L.
    Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden..
    Coreno, M.
    CNR, ISM, Tito, Pz, Italy.;Trieste LD2 Unit, Trieste, Italy..
    de Simone, M.
    Sincrotrone Trieste, Lab TASC, CNR, IOM, Trieste, Italy..
    Santagata, A.
    CNR, ISM, Tito, Pz, Italy.;Trieste LD2 Unit, Trieste, Italy..
    Brena, B.
    Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden..
    Puglia, C.
    Uppsala Univ, Dept Phys & Astron, Box 516, SE-75120 Uppsala, Sweden..
    Electronic structure modifications induced by increased molecular complexity: from triphenylamine to m-MTDATA2019In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 21, no 32, p. 17959-17970Article in journal (Refereed)
    Abstract [en]

    The starburst pi-conjugated molecule 4,4 ',4 ''-tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine (C57H48N4, m-MTDATA), based on triphenylamine (TPA) building blocks, is widely used in optoelectronic devices due to its good electron-donor characteristics. The electronic structure of m-MTDATA was investigated for the first time in the gas phase by means of PhotoElectron Spectroscopy (PES) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy. The combination of Density Functional Theory (DFT) calculations with the experimental spectra provides a comprehensive description of the molecular electronic structure. Moreover, by comparing the results with previous TPA measurements, we could shed light on how the electronic structure evolves when the molecular size is increased. We found that the C 1s photoelectron spectra of m-MTDATA and TPA are similar, due to the balance of the counter-acting effects of the electronegativity of the N atoms and the delocalization of the amine lone-pair electrons. In contrast, the increased number of N atoms (i.e. N lone pairs) in m-MTDATA determines a three-peak feature in the outermost valence binding energy region with strong contributions by the N 2p(z) orbitals. We also obtained a decrease of the HOMO-LUMO gap for m-MTDATA, which points to improved electron donating properties of m-MTDATA with respect to TPA.

  • 2434.
    Zhang, Wang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH). Karolinska institutet.
    Development of novel molecular and microfluidics tools for identification and characterization of latent HIV-1 reservoir2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The existence of latent HIV-1 reservoir (LR) in all HIV-1 infected patients serves as a major obstacle to completely cure HIV-1 infection. However, up to now there is still no available assay that provides an accurate measurement of the reservoir size. This thesis aims to address this challenge from different aspects with several novel technologies, using both molecular and microfluidics-based tools. To find a proper tool to identify the latent HIV-1 reservoir, in Paper I and II, LIPS assay, RNAflow, and RNAscope assay were optimized and evaluated for indirect and direct detection of latent HIV-1 reservoir. The results indicated the LIPS method might not be sufficient for latent HIV-1 reservoir detection, although it has been proposed to quantify the latent HIV-1 reservoir indirectly. Furthermore, the optimized RNAscope technique performed better than RNAflow for transcription and translation competent latent HIV-1 reservoir identification. The RNAscope was also found to be independent of the HIV-1 subtype and can be applied to patient samples at single cell level. As there are currently no available surface biomarkers for latent HIV-1 reservoir, in Paper III, transcriptomics and proteomics-based analysis method for high-throughput selection of potential biomarker were established and applied to different patient groups. Twelve membrane protein-coding genes were identified as downregulated in the patient group who were hypothesized to have lower latent reservoir. These proteins might have the potential to be used as surface biomarkers for latent HIV-1 reservoir. CD4+ T cells, monocyte/macrophages, and natural killer cells are believed to be the primary source for HIV-1 reservoirs in peripheral blood. In paper IV, a microfluidic chip was developed to simultaneously isolate these three mononuclear leukocyte cell types directly from whole blood. The microfluidic method reduces the sample volume requirement and is a promising tool for latent HIV-1 reservoir study. Together, though further improvement and clinical verification are necessary, the work in this thesis has contributed to the advancement of latent HIV-1 reservoir characterization and may facilitate future development of the latent HIV-1 reservoir targeting and clearance methods with the ultimate goal – to cure HIV-1 infection.

  • 2435.
    Zhang, Wang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Nano Biotechnology. karolinska institutet.
    Aljadi, Zenib
    Neogi, Ujjwal
    Russom, Aman
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Nano Biotechnology.
    Microfluidic based immunoaffinity mononuclear leukocytes isolation from whole bloodManuscript (preprint) (Other academic)
    Abstract [en]

    CD4+ T cells, monocyte/macrophages and natural killer cells are believed to be the main source for HIV-1 reservoirs in peripheral blood. However, despite the potential these subsets of providing a wealth of new information about immune function and host pathology, current HIV latency studies are often based on PBMCs or only CD4+ T cells, mainly due to the lack of appropriate cell subset isolation methods. We present here a microfluidic chip-based method to capture and enrich the three mononuclear cells sub-population peripheral leukocyte sub-populations: CD4+ lymphocytes, natural killer cells and monocytes; using a single source of whole blood (volume < 200 μL) on a single integrated platform, within a time frame of 20 min. The single step isolation method can be used for downstream proteomics and genomics analysis to study the aberrations in these cell types’ functions in critical diseases such as HIV.

  • 2436.
    Zhang, Wei
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Hua, Yong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Wang, Linqin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Zhang, Biaobiao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Li, Yuanyuan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Liu, Peng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Leandri, Valentina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Guo, Yu
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Chen, Hong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Gardner, James M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Sun, Licheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry. Dalian Univ Technol DUT, DUT KTH Joint Res Ctr Mol Devices, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Kloo, Lars
    The Central Role of Ligand Conjugation for Properties of Coordination Complexes as Hole-Transport Materials in Perovskite Solar Cells2019In: ACS APPLIED ENERGY MATERIALS, ISSN 2574-0962, Vol. 2, no 9, p. 6768-6779Article in journal (Refereed)
    Abstract [en]

    Two zinc-based coordination complexes Y3 and Y4 have been synthesized and characterized, and their performance as hole-transport materials (HTMs) for perovskite solar cells (PSCs) has been investigated. The complex Y3 contains two separate ligands, and the molecular structure can be seen as a disconnected porphyrin ring. On the other hand, Y4 consists of a porphyrin core and therefore is a more extended conjugated system as compared to Y3. The optical and redox properties of the two different molecular complexes are comparable. However, the hole mobility and conductivity of Y4 as macroscopic material are remarkably higher than that of Y3. Furthermore, when employed as hole-transport materials in perovskite solar cells, cells containing Y4 show a power conversion efficiency (PCE) of 16.05%, comparable to the Spiro-OMeTAD-based solar cells with an efficiency around 17.08%. In contrast, solar cells based on Y3 show a negligible efficiency of about 0.01%. The difference in performance of Y3 and Y4 is analyzed and can be attributed to the difference in packing of the nonplanar and planar building blocks in the corresponding materials.

  • 2437.
    Zhang, Wei
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Sadollahkhani, Azar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Li, Yuanyuan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Leandri, Valentina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Gardner, James M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Mechanistic Insights from Functional Group Exchange Surface Passivation: A Combined Theoretical and Experimental Study2019In: ACS APPLIED ENERGY MATERIALS, ISSN 2574-0962, Vol. 2, no 4, p. 2723-2733Article in journal (Refereed)
    Abstract [en]

    Four different functional groups including amino (-NH2), phosphine (-PH2), hydroxyl (-OH), and thiol (-SH) were combined with POSS (polyhedral oligomeric silsesquioxane) molecules to investigate how functional groups affect the surface passivation of POSS systems. Results from density-functional theory (DFT) calculations indicate that functional group amino (-NH2) with adsorption energy 86 (56) kJ mol(-1) is consistently better than that of thiol (-SH) with adsorption energy 68 (43) kJ mor(-1) for different passivation mechanisms. Theoretical studies on the analogous POSS-OH and POSS-PH2 systems show similar adsorption energies. Two of the systems were also investigated experimentally; aminopropyl isobutyl POSS (POSS-NH2) and mercaptopropyl isobutyl POSS (POSS-SH) were applied as passivation materials for MAPbI(3) (MA = methylammonium) perovskite and (FA)(0.85)(MA)(0.15)Pb(I-3)(0.85)(Br-3)(0)(.15)(FA = formamidinium) perovskite films. The same conclusion was drawn based on the results from contact angle studies, X-ray diffraction (XRD), and the stability of solar cells in ambient atmosphere, indicating the vital importance of choice of functional groups for passivation of the perovskite materials.

  • 2438.
    Zhang, Weiwei
    et al.
    Univ Sci & Technol China, Dept Astron, CAS Key Lab Res Galaxies & Cosmol, Hefei 230026, Anhui, Peoples R China.;Univ Sci & Technol China, Sch Astron & Space Sci, Hefei 230026, Anhui, Peoples R China.;Penn State Univ, Dept Mech & Nucl Engn, University Pk, PA 16802 USA..
    Si, Yubing
    Huanghe Sci & Technol Coll, Inst Nanostruct Funct Mat, Henan Prov Key Lab Nanocomposites & Applicat, Zhengzhou 450006, Henan, Peoples R China..
    Zhen, Junfeng
    Univ Sci & Technol China, Dept Astron, CAS Key Lab Res Galaxies & Cosmol, Hefei 230026, Anhui, Peoples R China.;Univ Sci & Technol China, Sch Astron & Space Sci, Hefei 230026, Anhui, Peoples R China..
    Chen, Tao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Linnartz, Harold
    Leiden Univ, Leiden Observ, Sackler Lab Astrophys, POB 9513, NL-2300 RA Leiden, Netherlands..
    Tielens, Alexander G. G. M.
    Leiden Univ, Leiden Observ, POB 9513, NL-2300 RA Leiden, Netherlands..
    Laboratory Photochemistry of Covalently Bonded Fluorene Clusters: Observation of an Interesting PAH Bowl-forming Mechanism2019In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 872, no 1, article id 38Article in journal (Refereed)
    Abstract [en]

    The fullerene C-60, one of the largest molecules identified in the interstellar medium (ISM), has been proposed to form top-down through the photochemical processing of large (more than 60 C atoms) polycyclic aromatic hydrocarbon (PAH) molecules. In this article, we focus on the opposite process, investigating the possibility that fullerenes form from small PAHs, in which bowl-forming plays a central role. We combine laboratory experiments and quantum chemical calculations to study the formation of larger PAHs from charged fluorene clusters. The experiments show that with visible laser irradiation, the fluorene dimer cation-[C13H9-C13H9](+)-and the fluorene trimer cation-[C13H9-C13H8-C13H9](+)-undergo photodehydrogenation and photoisomerization, resulting in bowl-structured aromatic cluster ions, C26H12+ and C39H20+, respectively. To study the details of this chemical process, we employ quantum chemistry that allows us to determine the structures of the newly formed cluster ions, to calculate the dissociation energies for hydrogen loss, and to derive the underlying reaction pathways. These results demonstrate that smaller PAH clusters (with less than 60 C atoms) can convert to larger bowled geometries that might act as building blocks for fullerenes, because the bowl-forming mechanism greatly facilitates the conversion from dehydrogenated PAHs to cages. Moreover, the bowl-forming induces a permanent dipole moment that-in principle-allows one to search for such species using radio astronomy.

  • 2439.
    Zhang, Wen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Gago-Ferrero, Pablo
    Swedish Univ Agr Sci, Dept Aquat Sci & Assessment, Box 7050, SE-75007 Uppsala, Sweden..
    Gao, Qiuju
    Umea Univ, Dept Chem, Linnaeus Vag 6, SE-90187 Umea, Sweden..
    Ahrens, Lutz
    Swedish Univ Agr Sci, Dept Aquat Sci & Assessment, Box 7050, SE-75007 Uppsala, Sweden..
    Blum, Kristin
    Umea Univ, Dept Chem, Linnaeus Vag 6, SE-90187 Umea, Sweden..
    Rostvall, Ande
    Swedish Univ Agr Sci, Dept Aquat Sci & Assessment, Box 7050, SE-75007 Uppsala, Sweden..
    Björlenius, Berndt
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Andersson, Patrik L.
    Umea Univ, Dept Chem, Linnaeus Vag 6, SE-90187 Umea, Sweden..
    Wiberg, Karin
    Swedish Univ Agr Sci, Dept Aquat Sci & Assessment, Box 7050, SE-75007 Uppsala, Sweden..
    Haglund, Peter
    Umea Univ, Dept Chem, Linnaeus Vag 6, SE-90187 Umea, Sweden..
    Renman, Gunno
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Evaluation of five filter media in column experiment on the removal of selected organic micropollutants and phosphorus from household wastewater2019In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 246, p. 920-928Article in journal (Refereed)
    Abstract [en]

    A bench-scale column experiment was performed to study the removal of 31 selected organic micropollutants (MPs) and phosphorus by lignite, xyloid lignite (Xylit), granular activated carbon (GAC), Polonite (R) and sand over a period of 12 weeks. In total 29 out of the 31 MPs showed removal efficiency > 90% by GAC with an average removal of 97 +/- 6%. Xylit and lignite were less efficient with an average removal of 80 +/- 28% and 68 +/- 29%, respectively. The removal efficiency was found to be impacted by the characterization of the sorbents and physicochemical properties of the compounds, as well as the interaction between the sorbents and compounds. For instance, Xylit and lignite performed well for relatively hydrophobic (log octanol/water partition coefficient (K-ow) >= 3) MPs, while the removal efficiency of moderately hydrophilic, highly hydrophilic and negatively charged MPs were lower. The organic sorbents were found to have more functional groups at their surfaces, which might explain the higher adsorption of MPs to these sorbents. The removal of several MPs improved after four weeks in sand, Xylit, GAC and lignite which may be related to increased biological activity and biofilm development. GAC and sand had limited ability to remove phosphorus (12 +/- 27% and 14 +/- 2%, respectively), while the calcium-silicate material Polonite (R) precipitated phosphorus efficiently and increased the total phosphorus removal from 12% to 96% after the GAC filter.

  • 2440.
    Zhang, Xian
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. Wuhan Univ Sci & Technol, State Key Lab Refractory Mat & Met, Hubei Prov Key Lab Syst Sci Met Proc, Int Res Inst Steel Technol, Wuhan 430081, Hubei, Peoples R China..
    Odnevall Wallinder, Inger
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Leygraf, Christopher
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Atmospheric corrosion of Zn-Al coatings in a simulated automotive environment2018In: Surface Engineering, ISSN 0267-0844, E-ISSN 1743-2944, Vol. 34, no 9, p. 641-648Article in journal (Refereed)
    Abstract [en]

    Accelerated NVDA (VDA 233-102) tests were performed on bare Zn and Al sheets, Galfan coating (Zn-5 wt-% Al) and Galvalume coating (Zn-55 wt-% Al) on steel. ZnO, Zn(OH)(2) and Zn-5(OH)(8)Cl-2 center dot H2O were the main corrosion products identified on both bare Zn sheet and Galfan. AlOOH and Al(OH)(3) were preferentially formed on bare Al sheet and Galvalume. In addition, Zn-Al-containing corrosion products, Zn6Al2(OH)(16)CO3 center dot 4H(2)O and/or Zn2Al(OH)(6)Cl center dot 2H(2)O were identified on both Galfan and Galvalume. Corrosion products of Zn6Al2(OH)(16)CO3 center dot 4H(2)O with a platelet morphology were preferentially formed in the zinc-rich interdendritic regions of the Galvalume surface. Galfan revealed a similar corrosion behaviour as bare Zn sheet, whereas Galvalume exhibited similar behaviour as bare Al sheet. Deposition of chlorides highly influenced the corrosion of both Galvalume and Al rather than Galfan and Zn due to the rapid local damage of the compact native thin film of Al2O3.

  • 2441.
    Zhang, Xianjie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Bogic, Sebastian
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Datautvinning av klickdata: Kombination av klustring och klassifikation2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Owners of websites and applications usually profits through users that clicks on their links. These can be advertisements or items for sale amongst others. There are many studies about data analysis where they tell you if a link will be clicked, but only a few that focus on what needs to be adjusted to get the link clicked. The problem that Flygresor.se have is that they are missing a tool for their customers, travel agencies, that analyses their tickets and after that adjusts the attributes of those trips. The requested solution was an application which gave suggestions about how to change the tickets in a way that would make it more clicked and in that way, make more sales. A prototype was constructed which make use of two different data mining methods, clustering with the algorithm DBSCAN and classification with the algorithm knearest neighbor. These algorithms were used together with an evaluation process, called DNNA, which analyzes the result from the algorithms and gave suggestions about changes that could be done to the attributes of the links. The combination of the algorithms and DNNA was tested and evaluated as the solution to the problem. The program was able to predict what attributes of the tickets needed to be adjusted to get the tickets more clicks. ‘The recommendations of adjustments were reasonable but this result could not be compared to similar tools since they had not been published.

  • 2442.
    Zhang, Xiaoliang
    et al.
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China..
    Cappel, Ute B.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Jia, Donglin
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China..
    Zhou, Qisen
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China..
    Du, Juan
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China..
    Sloboda, Tamara
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Svanström, Sebastian
    Uppsala Univ, Dept Phys & Astron, Div Mol & Condensed Matter Phys, Box 516, SE-75120 Uppsala, Sweden..
    Johansson, Fredrik O. L.
    Uppsala Univ, Dept Phys & Astron, Div Mol & Condensed Matter Phys, Box 516, SE-75120 Uppsala, Sweden..
    Lindblad, Andreas
    Uppsala Univ, Dept Phys & Astron, Div Mol & Condensed Matter Phys, Box 516, SE-75120 Uppsala, Sweden..
    Giangrisostomi, Erika
    Helmholtz Zentrum Berlin GmbH, Inst Methods & Instrumentat Synchrotron Radiat Re, Albert Einstein Str 15, D-12489 Berlin, Germany..
    Ovsyannikov, Ruslan
    Helmholtz Zentrum Berlin GmbH, Inst Methods & Instrumentat Synchrotron Radiat Re, Albert Einstein Str 15, D-12489 Berlin, Germany..
    Liu, Jianhua
    Beihang Univ, Sch Mat Sci & Engn, Beijing 100191, Peoples R China..
    Rensmo, Håkan
    Uppsala Univ, Dept Phys & Astron, Div Mol & Condensed Matter Phys, Box 516, SE-75120 Uppsala, Sweden..
    Gardner, James M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Johansson, Erik M. J.
    Uppsala Univ, Phys Chem, Dept Chem Angstrom, S-75120 Uppsala, Sweden..
    Probing and Controlling Surface Passivation of PbS Quantum Dot Solid for Improved Performance of Infrared Absorbing Solar Cells2019In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 31, no 11, p. 4081-4091Article in journal (Refereed)
    Abstract [en]

    Surface properties of colloidal quantum dots (CQDs) are critical for the transportation and recombination of the photoinduced charge carrier in CQD solar cells, therefore dominating the photovoltaic performance. Herein, PbS CQD passivated using liquid-state ligand exchange (LSLX) and solid-state ligand exchange (SSLX) strategies are in detail investigated using photoelectron spectroscopy (PES), and solar cell devices are prepared to understand the link between the CQD surface properties and the solar cell function. PES using different energies in the soft and hard Xray regime is applied to study the surface and bulk properties of the CQDs, and the results show more effective surface passivation of the CQDs prepared with the LSLX strategy and less formation of lead-oxide. The CQD solar cells prepared with LSLX strategy show higher performance, and the photoelectric measurements suggest that the recombination of photoinduced charges is reduced for the solar cell prepared with the LSLX approach. Meanwhile, the fabricated solar cells exhibit good stability. This work provides important insights into how to fine-tune the CQD surface properties by improving the CQD passivation, and how this is linked to further improvements of the device photovoltaic performance.

  • 2443.
    Zhang, Yang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    A visualization interface for spatial pathway regulation data2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Data visualization is an essential methodology for bioinformatics studies. Spatial Transcriptomics(ST) is a method that aims at measuring the transcriptome of tissue sections while maintaining its spacial information. Finally, the study of biological pathway focuses on a series of biochemical reactions that take place in organisms. As these studies generate a large number of datasets, this thesis attempts to combine the ST’s data with pathwayinformation and visualize it in an intuitive way to assist user comprehension and insight.In this thesis, Python was used for integrating the dataset and JavaScript libraries wereused for building the visualization. The processing of ST pathway data together with the data visualization interface are the outcomes of this thesis. The data visualization can show the regulation of pathways in the ST data and can be accessed by modern browsers. These outcomes can help users navigate the ST and pathway datasets more effectively.

  • 2444.
    Zhang, Yang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Integration of Distributed Renewable Energy and Energy Storages in Buildings2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Photovoltaic (PV) is a distributed renewable energy technology that is suitable for integration in buildings. PV reduces the electricity demands as well as the greenhouse gas emissions of buildings. However, the surplus electricity from PV is exported to the electricity grid, which not only lowers the economic performance of the PV but also creates operational problems in the grid. Efficient approaches should be identified to improve PV’s economic and environmental performance.

    Buildings differ by their connections to energy networks. In buildings that are only connected to the electricity grid, electrical energy storages— including battery and hydrogen storage—can mitigate the mismatch between production and consumption. When a grid-connected PV system follows the conventional operation strategy, its economic performance worsens with storage. Two new operation strategies are developed. With a developed optimization framework, operation strategies and storage capacities are optimized simultaneously. Optimization results indicate that both net present value and self-sufficiency ratio are increased by storages. A comparison between battery storages and hydrogen storages shows that the hydrogen storage can compete with the battery counterpart under an optimistic hydrogen storage cost scenario. In addition, the hydrogen storage can better decrease the exported electricity.

    In buildings that are connected to the electricity grid and the district heating network, additional energy conversion and storage equipment— including heat pumps, electrical heaters, and hot water tanks—can be installed to form an integrated energy system (IES). After optimal system sizing, the IES decreases the net present cost by 22%, and the self-consumption ratio increases from 43% to 61%. Moreover, the IES serves as a new flexibility measure, and the provided flexibility energy is over 36% of its electricity consumption. During system planning, the system configuration and operation cost are obtained without considering forecast errors. Through the year-round simulation of system operation that considers forecast errors, a corrected operation cost is obtained. The yearly operation cost difference between system operation and system planning is less than 4% and 6% under the high and low forecast accuracy scenarios.

    The full text will be freely available from 2019-12-31 12:46
  • 2445.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Lundblad, Anders
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Wandong, Zheng
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Planning and Operation of an Integrated Energy System in a Swedish BuildingManuscript (preprint) (Other academic)
    Abstract [en]

    The increasing capacities of variable renewable energies (VRE) require more flexibility measures. The integration of energy supplies in buildings forms integrated energy systems (IES). IESs can provide flexibility and help increase the VRE penetration level. To upgrade a current building energy system into an IES, several energy conversion and storage components need to be installed. How to decide the component capacities and operate the IES were investigated separately in studies on system planning and system operation. However, a research gap exists that the system configuration from system planning is not validated by real operation conditions in system operation. Meanwhile, studies on system operation assume that the IES configuration is predetermined. This work combines system planning and system operation. The IES configuration is determined by mixed integer linear programming in system planning. Real operation conditions and forecast errors are considered in the system operation. The operation profiles are obtained through different energy management systems. The results indicate that the system configuration from system planning can meet energy demands in real operation conditions. Among different energy management systems, the combination of robust optimization and receding horizon optimization achieves the lowest yearly operation cost. Meanwhile, two scenarios that represent high and low forecast accuracies are employed. Under the high and low forecast accuracy scenarios, the yearly operation costs are about 4% and 6% higher than those obtained from system planning.

  • 2446.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen Univ, Sch Business Soc & Engn, SE-72123 Västerås, Sweden..
    Yang, Ying
    Mälardalen Univ, Sch Business Soc & Engn, SE-72123 Västerås, Sweden..
    Lundblad, Anders
    RISE Res Inst Sweden, Div Safety & Transport Elect, SE-50462 Borås, Sweden..
    Yan, Jerry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen Univ, Sch Business Soc & Engn, SE-72123 Västerås, Sweden..
    Energy Flexibility through the Integrated Energy Supply System in Buildings: A Case Study in Sweden2018In: RENEWABLE ENERGY INTEGRATION WITH MINI/MICROGRID / [ed] Yan, J Wang, C Yu, J Jia, H Wu, J Xu, T Zhang, Y, ELSEVIER SCIENCE BV , 2018, p. 564-569Conference paper (Refereed)
    Abstract [en]

    The increasing penetration level of renewable energies requires more flexibility measures at the consumption side. Flexible energy prices have been placed by energy providers to promote flexibility measures from energy users. However, because of the current energy supply system in buildings, these flexible energy prices haven't been fully taken advantage of This study focuses on the integrated energy supply system in buildings. A Swedish office building is used as the case study. The integrated energy supply system is built by installing new components, including battery, heat pump and electrical heater, and hot water tank. Mixed Integer Linear Programming (MILP) problems are solved to determine the optimal component capacities and operation profiles. The results indicate that all the studied system configurations achieve lower net present cost (NPC) than the current system. It suggests that the integrated energy supply system can take advantage of the flexible energy prices and lower the overall energy cost in the building. Among the studied configurations, the combination of air source heat pump (ASHP) and electrical heater (EH) has the lowest investment cost. This combination also has the lowest NPC except in the scenario with low borehole cost.

  • 2447.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen University, Västerås, Sweden.
    Yang, Ying
    Stridh, Bengt
    Lundblad, Anders
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen University, Västerås, Sweden.
    Energy flexibility from the consumer: Integrating local electricity and heat supplies in a building2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 223, p. 430-442Article in journal (Refereed)
    Abstract [en]

    The increasing penetration level of renewable energy requires more flexibility measures to be implemented in future energy systems. Integrating an energy consumer's local energy supplies connects multiple energy networks (i.e., the electrical grid, the district heating network, and gas network) in a decentralized way. Such integration enhances the flexibility of energy systems. In this work, a Swedish office building is investigated as a case study. Different components, including heat pump, electrical heater, battery and hot water storage tank are integrated into the electricity and heat supply system of the building. Special focus is placed on the flexibility that the studied building can provide to the electrical grid (i.e., the building modulates the electricity consumption in response to the grid operator's requirements). The flexibility is described by two metrics including the flexibility hours and the flexibility energy. Optimization of the component capacities and the operation profiles is carried out by using Mixed Integer Linear Programming (MILP). The results show that the system fully relies on electricity for the heat demand when not considering the flexibility requirements of the electrical grid. This suggests that district heating is economically unfavorable compared with using electricity for the heat demand in the studied case. However, when flexibility requirements are added, the system turns to the district heating network for part of the heat demand. The system provides great flexibility to the electrical grid through such integration. The flexibility hours can be over 5200 h in a year, and the flexibility energy reaches more than 15.7 MWh (36% of the yearly electricity consumption). The yearly operation cost of the system slightly increases from 62,273 to 65,178 SEK when the flexibility hours increase from 304 to 5209 h. The results revealed that flexibility can be provided from the district heating network to the electrical grid via the building.

  • 2448.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Xie, Sheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Yan, Mingdi
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Ramström, Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Organic chemistry.
    Enzyme- and ruthenium-catalyzed dynamic kinetic resolution involving cascade alkoxycarbonylations for asymmetric synthesis of 5-Substituted N-Aryloxazolidinones2019In: Molecular Catalysis, ISSN 2468-8231, Vol. 470, p. 138-144Article in journal (Refereed)
    Abstract [en]

    AAsymmetric synthesis of N-aryloxazolidinones via dynamic kinetic resolution was developed. A ruthenium-based catalyst was used in the racemization of beta-anilino alcohols, while Candida antarctica lipase B (CAL-B) was applied for two selective alkoxycarbonylations operating in cascade. Various N-aryloxazolidinone derivatives were obtained in high yields and good enantiopurities.

  • 2449.
    Zhang, Yongfei
    et al.
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, Dalian 116024, Peoples R China..
    Liang, Yongqi
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, Dalian 116024, Peoples R China..
    Wang, Yajuan
    DUT, DUT KTH Joint Educ & Res Ctr Mol Devices, State Key Lab Fine Chem, Inst Artificial Photosynth, Dalian 116024, Peoples R China..
    Guo, Fengwan
    Peking Univ, Beijing Natl Lab Mol Sci, State Key Lab Struct Chem Unstable & Stable Speci, Coll Chem & Mol Engn, Beijing 100871, Peoples R China..
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Xu, Dongsheng
    Peking Univ, Beijing Natl Lab Mol Sci, State Key Lab Struct Chem Unstable & Stable Speci, Coll Chem & Mol Engn, Beijing 100871, Peoples R China..
    Planar FAPbBr(3) Solar Cells with Power Conversion Efficiency above 10%2018In: ACS ENERGY LETTERS, ISSN 2380-8195, Vol. 3, no 8, p. 1808-1814Article in journal (Refereed)
    Abstract [en]

    Bromide-based hybrid perovskites are of particular interest not only due to the fact that they offer a way to go beyond the Shockley-Queisser limit via the tandem cell scheme but single junction devices of them can also achieve reasonably high efficiency with high stability for solar energy conversion. However, the highest power conversion efficiency achieved up to now for FAPbBr(3) single-junction solar cells is only 8.2%, which is far below the efficiency of-17% predicted from detailed balance analysis. Here, a two-step method (the intermolecule exchange pathway) was systematically optimized for the fabrication of high quality FAPbBr(3) films. A molecule of urea, structurally similar to formamidinium, is introduced as an additive to tune the intermolecular ion exchange procedure. SnO2 is introduced as an electron-selective contact to the planar structured FAPbBr(3) solar cells. As a result, a power conversion efficiency of 10.61% and a V-oc of 1.56 V are achieved with planar structured solar cells, both of which represent the highest value ever reported for FAPbBr(3) solar cells.

  • 2450.
    Zhang, Yuning
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Andrén, Oliver C. J.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Nordström, R.
    Fan, Yanmiao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Malmsten, M.
    Mongkhontreerat, S.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Off-Stoichiometric Thiol-Ene Chemistry to Dendritic Nanogel Therapeutics2019In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 29, no 18, article id 1806693Article in journal (Refereed)
    Abstract [en]

    A novel platform of dendritic nanogels is herein presented, capitalizing on the self-assembly of allyl-functional polyesters based on dendritic-linear-dendritic amphiphiles followed by simple cross-linking with complementary monomeric thiols via UV initiated off-stoichiometric thiol-ene chemistry. The facile approach enabled multigram creation of allyl reactive nanogel precursors, in the size range of 190–295 nm, being readily available for further modifications to display a number of core functionalities while maintaining the size distribution and characteristics of the master batch. The nanogels are evaluated as carriers of a spread of chemotherapeutics by customizing the core to accommodate each individual cargo. The resulting nanogels are biocompatible, displaying diffusion controlled release of cargo, maintained therapeutic efficacy, and decreased cargo toxic side effects. Finally, the nanogels are found to successfully deliver pharmaceuticals into a 3D pancreatic spheroids tumor model. © 2019 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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