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  • 121901. Zhou, Z. -Q
    et al.
    Liu, X.
    Kedem, Yaron
    KTH, Centres, Nordic Institute for Theoretical Physics NORDITA.
    Cui, J. -M
    Li, Z. -F
    Hua, Y. -L
    Li, C. -F
    Guo, G. -C
    Experimental observation of anomalous trajectories of single photons2017In: Physical Review A. Atomic, Molecular, and Optical Physics, ISSN 1050-2947, E-ISSN 1094-1622, Vol. 95, no 4, article id 042121Article in journal (Refereed)
    Abstract [en]

    A century after its conception, quantum mechanics still hold surprises that contradict many "common sense" notions. The contradiction is especially sharp in case one consider trajectories of truly quantum objects such as single photons. From a classical point of view, trajectories are well defined for particles, but not for waves. The wave-particle duality forces a breakdown of this dichotomy and quantum mechanics resolves this in a remarkable way: Trajectories can be well defined, but they are utterly different from classical trajectories. Here, we give an operational definition to the trajectory of a single photon by introducing a technique to mark its path using its spectral composition. The method demonstrates that the frequency degree of freedom can be used as a bona fide quantum measurement device (meter). The analysis of a number of setups, using our operational definition, leads to anomalous trajectories which are noncontinuous and in some cases do not even connect the source of the photon to where it is detected. We carried out an experimental demonstration of these anomalous trajectories using a nested interferometer. We show that the two-state vector formalism provides a simple explanation for the results. © 2017 American Physical Society.

  • 121902.
    Zhou, Zhou
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Li, Xiaogai
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Kleiven, Svein
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Biomechanics of acute subdural hematoma in the elderly: A fluid-structure interaction study2018In: Journal of Neurotrauma, ISSN 0897-7151, E-ISSN 1557-9042Article in journal (Refereed)
    Abstract [en]

    Acute subdural hematoma (ASDH) due to bridging vein (BV) rupture is a frequent and lethal head injury, especially in the elderly. Brain atrophy has been hypothesized to be a primary pathogenesis associated with the increased risk of ASDH in the elderly. Though decades of biomechanical endeavours have been made to elucidate the potential mechanisms, a thorough explanation for this hypothesis appears lacking. Thus, a recently improved finite element head model, in which the brain-skull interface was modelled using a fluid-structure interaction (FSI) approach with special treatment of the cerebrospinal fluid as arbitrary Lagrangian-Eulerian fluid formulation, is used to partially address this understanding gap. Models with various degrees of atrophied brains and thereby different subarachnoid thicknesses are generated and subsequently exposed to experimentally determined loadings known to cause ASDH or not. The results show significant increases in the cortical relative motion and BV strain in the atrophied brain, which consequently exacerbates the ASDH risk in the elderly. Results of this study are suggested to be considered while developing age-adapted protecting strategies for the elderly in the future.

  • 121903.
    Zhou, Zhou
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Li, Xiaogai
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Kleiven, Svein
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Fluid–structure interaction simulation of the brain–skull interface for acute subdural haematoma prediction2018In: Biomechanics and Modeling in Mechanobiology, ISSN 1617-7959, E-ISSN 1617-7940, Vol. 18, no 1, p. 155-173Article in journal (Refereed)
    Abstract [en]

    Traumatic brain injury is a leading cause of disability and mortality. Finite element-based head models are promising tools for enhanced head injury prediction, mitigation and prevention. The reliability of such models depends heavily on adequate representation of the brain–skull interaction. Nevertheless, the brain–skull interface has been largely simplified in previous three-dimensional head models without accounting for the fluid behaviour of the cerebrospinal fluid (CSF) and its mechanical interaction with the brain and skull. In this study, the brain–skull interface in a previously developed head model is modified as a fluid–structure interaction (FSI) approach, in which the CSF is treated on a moving mesh using an arbitrary Lagrangian–Eulerian multi-material formulation and the brain on a deformable mesh using a Lagrangian formulation. The modified model is validated against brain–skull relative displacement and intracranial pressure responses and subsequently imposed to an experimentally determined loading known to cause acute subdural haematoma (ASDH). Compared to the original model, the modified model achieves an improved validation performance in terms of brain–skull relative motion and is able to predict the occurrence of ASDH more accurately, indicating the superiority of the FSI approach for brain–skull interface modelling. The introduction of the FSI approach to represent the fluid behaviour of the CSF and its interaction with the brain and skull is crucial for more accurate head injury predictions.

  • 121904.
    Zhou, Zhou
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Li, Xiaogai
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Kleiven, Svein
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Shah, C.S.
    Hardy, W.N.
    A reanalysis of experimental brain strain data: implication for finite element head model validation2018In: Stapp Car Crash Journal, ISSN 1532-8546, Vol. 62, p. 293-318Article in journal (Refereed)
    Abstract [en]

    Relative motion between the brain and skull and brain deformation are biomechanics aspects associated with many types of traumatic brain injury (TBI). Thus far, there is only one experimental endeavor (Hardy et al., 2007) reported brain strain under loading conditions commensurate with levels that were capable of producing injury. Most of the existing finite element (FE) head models are validated against brain-skull relative motion and then used for TBI prediction based on strain metrics. However, the suitability of using a model validated against brain-skull relative motion for strain prediction remains to be determined. To partially address the deficiency of experimental brain deformation data, this study revisits the only existing dynamic experimental brain strain data and updates the original calculations, which reflect incremental strain changes. The brain strain is recomputed by imposing the measured motion of neutral density target (NDT) to the NDT triad model. The revised brain strain and the brain-skull relative motion data are then used to test the hypothesis that an FE head model validated against brainskull relative motion does not guarantee its accuracy in terms of brain strain prediction. To this end, responses of brain strain and brain-skull relative motion of a previously developed FE head model (Kleiven, 2007) are compared with available experimental data. CORrelation and Analysis (CORA) and Normalized Integral Square Error (NISE) are employed to evaluate model validation performance for both brain strain and brain-skull relative motion. Correlation analyses (Pearson coefficient) are conducted between average cluster peak strain and average cluster peak brain-skull relative motion, and also between brain strain validation scores and brain-skull relative motion validation scores. The results show no significant correlations, neither between experimentally acquired peaks nor between computationally determined validation scores. These findings indicate that a head model validated against brain-skull relative motion may not be sufficient to assure its strain prediction accuracy. It is suggested that a FE head model with intended use for strain prediction should be validated against the experimental brain deformation data and not just the brain-skull relative motion.

  • 121905. Zhou, Zude
    et al.
    Yao, Bitao
    Xu, Wenjun
    Wang, Lihui
    KTH, School of Industrial Engineering and Management (ITM), Production Engineering, Production Systems.
    Condition monitoring towards energy-efficient manufacturing: a review2017In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 91, no 9-12, p. 3395-3415Article, review/survey (Refereed)
    Abstract [en]

    Recently, sustainable development has obtained increasing attentions from governments, industry, and academia owing to the limited natural resources. In the area of energy consumption, manufacturing accounts for a major portion of the total energy usage in industry. There is a clear necessity for energy-efficient manufacturing by optimizing manufacturing activities. Condition monitoring is the technology that provides runtime information for optimization. This paper aims to provide a better understanding of past achievements and future trends of condition monitoring towards energy-efficient manufacturing. Since there are a variety of sensors and technologies that can be used for condition monitoring towards energy-efficient manufacturing, this paper divides manufacturing activities into three levels, namely unit process level, shop-floor level, and supply chain level, and summarizes and discusses the sensors and technologies required to enable energy-efficient manufacturing on each level. With the advancement of technology, condition monitoring shows the characteristic of intelligence. Intelligent sensors that can be applied to condition monitoring in energy-efficient manufacturing are also reviewed. This paper can be helpful to manufacturers who are willing to improve energy efficiency in own manufacturing practice.

  • 121906.
    Zhovtobriukh, Iurii
    et al.
    Stockholm Univ, FYSIKUM, AlbaNova Univ Ctr, SE-10691 Stockholm, Sweden..
    Norman, Patrick
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Pettersson, Lars G. M.
    Stockholm Univ, FYSIKUM, AlbaNova Univ Ctr, SE-10691 Stockholm, Sweden..
    X-ray absorption spectrum simulations of hexagonal ice2019In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 150, no 3, article id 034501Article in journal (Refereed)
    Abstract [en]

    We calibrate basis sets and performance of two theoretical approaches to compute X-ray absorption spectra (XAS) of condensed water by comparison to experiments on hexagonal ice Ih. We apply both the transition-potential half-core-hole approach and the complex polarization propagator using four different models of the crystal with increasing oxygen and proton disorder but find poor agreement with experiments. We note that there are large variations in experimental spectra depending on detection mode and how the ice samples were prepared, which leads us to critically investigate what structures were actually prepared and measured in each case. This is done by using a Monte Carlo-based fitting technique which fits the spectra based on a library of precomputed spectra and assigns weights to contributions from different model structures. These are then used to generate O-O and O-H radial distribution functions and tetrahedrality parameters associated with each of the measured spectra. We find that all spectra are associated with sharp peaks at the oxygen positions in the perfect lattice, but with significant disorder around these positions. We suggest that presently available XAS of hexagonal ice are not fully representative of the perfect crystalline lattice, but contain varying amounts of defects and possible contributions from low-density amorphous ice.

  • 121907. Zhow, Yongjin J.
    et al.
    Buijs, Nicolaas A.
    Zhu, Zhiwei
    Gomez, Diego Orol
    Boonsombuti, Akarin
    Siewers, Verena
    Nielsen, Jens
    KTH, School of Biotechnology (BIO), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab. Chalmers University of Technology, Sweden; Technical University of Denmark, Denmark.
    Harnessing Yeast Peroxisomes for Biosynthesis of Fatty-Acid-Derived Biofuels and Chemicals with Relieved Side-Pathway Competition2016In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 138, no 47, p. 15368-15377Article in journal (Refereed)
    Abstract [en]

    Establishing efficient synthetic pathways for microbial production of biochemicals is often hampered by competing pathways and/or insufficient precursor supply. Compartmentalization in cellular organelles can isolate synthetic pathways from competing pathways, and provide a compact and suitable environment for biosynthesis. Peroxisomes are cellular organelles where fatty acids are degraded, a process that is inhibited under typical fermentation conditions making them an interesting workhouse for production of fatty-acid-derived molecules. Here, we show that targeting synthetic pathways to peroxisomes can increase the production of fatty-acid-derived fatty alcohols, alkanes and olefins up to 700%. In addition, we demonstrate that biosynthesis of these chemicals in the peroxisomes results in significantly decreased accumulation of byproducts formed by competing enzymes. We further demonstrate that production can be enhanced up to 3-fold by increasing the peroxisome population. The strategies described here could be used for production of other chemicals, especially acyl-CoA-derived molecules.

  • 121908.
    Zhu, Anlin
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Rail Vehicles.
    Railway Infrastructure Management - System Engineering and Requirement Management2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Rail Control Solutions (RCS) is one division of Bombardier Transportation, aimed at optimising flow of trains. OPTIFLO is a new solution package within RCS, providing services and solutions to address challenges in modern railway infrastructures worldwide. Infrastructure Management (IM) Service is a significant sub-module under OPTIFLO, performing monitoring and diagnostic functionalities for each impacted system or component in railway signalling systems to continuously improve safety, reliability and availability.

    Requirement management is a significant stage while dealing with engineering problems. In this master thesis project, three modules in railway signalling scope are focused, including system level Infrastructure Management, sub-system level Maintenance and Diagnostic Centre (MDC) and sub-system level Remote Sensor Unit (RSU). For each part, requirement managements have been implemented, referring to CENELEC standards where necessary. The work starts with the draft Requirement Specification for IM and then identify the requirements related to diagnostics and performance in each sub-system. Both links between the requirements in different modules and links between the requirements and their test cases are built from the requirement management tool DOORS to realize verification and validation following the system engineering process. Finally, the standard documentations "System Requirement Specification" for each impacted module that are mostly concerned in the thesis have been released.

  • 121909.
    Zhu, Anqing
    KTH, School of Architecture and the Built Environment (ABE), Architecture.
    Translation From Image to Building2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    After the fire accident, KTH school of architecture is no longer in its best performance. The school indeed need an extension. However, through out this thesis project, I attempt to take one step further. It is not only to construct a functional school, but reconsider the meaning of architectural education. I am interested in three aspects, which all of them has being driving forces to this project. Firstly, I was interested in memory of the old architecture school in Stockholm, which was accommodated in a 19th centry wooden building. It was old and small, but students loved it. One’s memory of certain places would shape his thinking and values as an architect. Therefore, my design attempts to bring back such a memory by study some of the details in the old building and bring them back into the new extension with a twist. Secondly, in terms of working method I am very much resisted to ‘Graphic Architecture’, models always come together with rending images. They are offered to read side by side. The rending images are not trying to present the final products but also used as a development tool. Overall this project was developed from the inside towards the outside. The aim was to make an ordinary building with some thoughtful touches.

  • 121910. Zhu, B.
    et al.
    Fan, L.
    Deng, H.
    He, Y.
    Afzal, M.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Dong, W.
    Yaqub, A.
    Janjua, N. K.
    Erratum: Corrigendum to “LiNiFe-based layered structure oxide and composite for advanced single layer fuel cells” (J. Power Sources (2016) 316 (37–43))2016In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 324Article in journal (Refereed)
    Abstract [en]

    The authors regret that the name of author Yunjuan He was misspelled as ‘Yunjune He’ in the original article. The authors would like to apologise for any inconvenience caused.

  • 121911.
    Zhu, B.
    et al.
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID.
    Hedman, Anders
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID.
    Li, Haibo
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID.
    Design digital mindfulness for personal wellbeing2016In: Proceedings of the 28th Australian Computer-Human Interaction Conference, OzCHI 2016, Association for Computing Machinery, Inc , 2016, p. 626-627Conference paper (Refereed)
    Abstract [en]

    The digital health and wellbeing movement has led to development of what we here baptize as digital mindfulness applications that allow people to improve psychological wellbeing. The approaches to digital mindfulness vary greatly and as a researcher it can be difficult to gain an overview of the field and what to focus on in one's own research. Here we describe four levels of digital mindfulness with examples and focus on the larger question of how to design for digital mindfulness. We end up with a set of general issues that we hope will generate further discussion and research in the field of digital mindfulness. 

  • 121912. Zhu, B.
    et al.
    Lindbergh, Göran
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Corrosion behaviour of high-chromium ferritic steels in molten carbonate in cathode environment2001In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 46, no 17, p. 2593-2604Article in journal (Refereed)
    Abstract [en]

    The corrosion behaviour of four ferritic steels with a high chromium content and AISI 310 was investigated in (Li-0.60/Na-0.40)(2)CO3 melt in three different cathode gas environments. The electrochemical techniques used were linear polarisation resistance and Tafel extrapolation. The corrosion layers formed on the surface during the tests were analysed by glow discharge optical emission spectroscopy (GDOES), The corrosion layer formed on the Thermax 4762 sample consists of an iron-rich outer layer and a protective aluminium- and chromium-rich inner layer. The corrosion potential increased to a more positive value as the corrosion layer grew on the surface. This supports the supposition that the cathodic reaction in the corrosion process changes gradually from water reduction to oxygen reduction. It was shown that higher temperatures and low concentrations of oxygen and carbon dioxide under so-called outlet cathode gas conditions result in higher corrosion rates.

  • 121913. Zhu, B.
    et al.
    Lund, P. D.
    Raza, Rizwan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. COMSATS Institute of Information Technology, Pakistan .
    Ma, Y.
    Fan, L.
    Afzal, Muhammad
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Patakangas, J.
    He, Y.
    Zhao, Y.
    Tan, W.
    Huang, Q. -A
    Zhang, J.
    Wang, H.
    Schottky junction effect on high performance fuel cells based on nanocomposite materials2015In: Advanced Energy Materials, ISSN 1614-6832, Vol. 5, no 8, article id 1401895Article in journal (Refereed)
    Abstract [en]

    A novel fuel cell device based on integrating the Schottky junction effect with the electrochemical principle is designed, constructed, and verified through experiments. It is found that the Schottky junction has a significant effect on the greatly enhanced device performance, and the fuel cell device incorporating the Schottky junction effect reaches a power output of 1000 mW cm-2 at 550 C.

  • 121914. Zhu, B.
    et al.
    Lv, F.
    Ma, D.
    Zhou, Helin
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    A pocket discharge model for narrow bipolar events and possible applications2010In: 2010 Asia-Pacific Symposium on Electromagnetic Compatibility, APEMC 2010, 2010, p. 1558-1561Conference paper (Refereed)
    Abstract [en]

    Narrow bipolar events refer to a distinct type of in-cloud lightning discharge which produces electric field of bipolar and impulse in nature. In this presentation narrow bipolar events were considered as the discharge of the pocket charge to the charge layer inside thundercloud, and the current wave-shape possibly responsible for the narrow bipolar electromagnetic field was featured by two channel-conducting-state depended parameters (α,β). The parameter β inversely reflects the time for the current front to propagate along the channel and can be achieved by the perfect fit of the measured field waveform to the model field waveform with the channel length and current propagation speed bound by the parameter β. The present model was applied to the narrow bipolar fields of two narrow bipolar events to reach a parameter β of 0.333μs-1 and 0.353μs-1 respectively, indicating a channel length less than 1km.

  • 121915. Zhu, B.
    et al.
    Zhou, Helin
    University of Science and Technology of China, Hefei, Anhui, China.
    Ma, M.
    Lv, F.
    Tao, S.
    Estimation of channel characteristics of narrow bipolar events based on the transmission-line model2010In: Journal of Geophysical Research, ISSN 0148-0227, E-ISSN 2156-2202, Vol. 115, no 19, p. D19105-Article in journal (Refereed)
    Abstract [en]

    Narrow bipolar event (NBE) is a distinct class of intracloud lightning discharge, which is associated with the strongest radio frequency emissions and produces typical narrow bipolar radiation field waveforms. On the basis of the transmission-line model, we introduce a direct technique to measure the time taken by the current front to propagate along the channel from distant radiation field pulses; the channel length of the NBE can then be estimated by multiplying this time by an assumed propagation speed. Our method involves integrating over the initial half cycle of narrow bipolar waveform of the NBE. The ratio of the integral result to the initial peak amplitude makes a good approximation to the time taken by the current front to travel along the channel, even though the current amplitude suffers heavy attenuation along the propagating channel. This method can be applied to all NBEs which produce narrow bipolar radiation field waveforms. Besides, if both the far radiation field and the near-electrostatic field measurements were available, one could combine the method here and that of Eack (2004) to obtain the channel length of the NBE.

  • 121916.
    Zhu, Baohua
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Corrosion of current cullector materials in the molten carbonate fuel cell2000Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    The corrosion of current collector materials in MoltenCarbonate Fuel Cells (MCFC) is investigated. The essential aimsof this investigation were to study the corrosion behaviour ofdifferent materials, in varying cathode and anode MCFCenvironments, and to study the contact corrosion resistancesbetween the MCFC current collector and electrodes. For thesepurposes, pure iron, iron-chromium binary alloys and severalcommercial steels were investigated in molten carbonate meltswithin the pot-cell laboratory set-up. In addition, the contactcorrosion resistances, between an AISI 310 current collectorand two cathodes (NiO and LiCoO2), were studied in a laboratory fuel cell.Post-tests were done to study the corrosion products formed atthe surfaces.

    In cathode environments, corrosion potential increased overtime as a protective corrosion layer slowly formed. Eventually,the potential reached a stable value close to the cathodeoperating potential. The main cathode reaction, as corrosionpotential increased, changed from water reduction to oxygenreduction. Corrosion rate under the operating cathode conditiondepended on the chromium content; the higher the concentrationof chromium, the lower the corrosion rate. The corrosion ratesof ferritic steels, with high chromium content, and AISI 310were higher at the so-called outlet operating condition incomparison to the standard and so-called inlet conditions. Thecorrosion rate was higher at the beginning of the exposure,which resulted in a relatively fast corrosion layer growth thatslowed as the protective layer was formed. It was shown thatthe corrosion layers, formed on iron-chromium alloys, AISI 310and ferritic high chromium-containing steels, consisted of twolayers. The outer layer was porous and iron rich, while theinner layer was quite compact and rich in chromium and/oraluminiumTherefore, the corrosion behaviour was dependent onthe corrosion layer structure at the metal surface.

    In anode environments, the beneficial behaviour of aluminiumin ferritic alloys, with high aluminium contents, was due tothe formation of aluminium oxide and/or lithium aluminium oxideat the surface. The corrosion rates at the standard and outletconditions were of the same order of magnitude, while thecorrosion rates at the inlet conditions were considerablyhigher. The lower temperatures and higher carbon dioxideconcentrations in the inlet conditions appeared to result in asurface layer deficient in aluminium. A modified theoreticalmodel was developed to evaluate the corrosion current densitiesfrom experimental polarisation curves or linear polarisationresistance measurements in anode environments. The fittingswere found to be very good.

    An experimental method was developed forin-situmeasurements of the contributions to the totalohmic losses at the cathode in a laboratory scale MCFC. Thecontact resistance between the cathode and current collectorcontributed quite a large value to the total cathodepolarization. The corrosion layer, formed between the LiCoO2cathode and AISI 310 current collector, wasiron-rich and more porous, and contained a small amount ofcobalt. This was deemed to consist of a two-phase oxide, whichresulted in a lower conductivity. The corrosion layer, formedbetween the NiO cathode and AISI 310 current collector, wasrich in nickel. The corrosion layers on the AISI 310, incontact with the cathode, had a different composition comparedto samples immersed in carbonate melts.

    Key words: molten carbonate fuel cell (MCFC), corrosion,current collector, contact corrosion resistance.

  • 121917.
    Zhu, Baohua
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Lindbergh, Göran
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Simonsson, Daniel
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Comparison of electrochemical and surface characterisation methods for investigation of corrosion of bipolar plate materials in molten carbonate fuel cell Part I. Electrochemical study1999In: Corrosion Science, Vol. 41, no 8, p. 1497-1513Article in journal (Refereed)
    Abstract [en]

    The corrosion of bipolar plate and current collector materials in molten carbonate fuel cells (MCFC) was investigated. Tafel extrapolation, linear polarisation resistance, chronopotentiometry and electrochemical impedance spectroscopy (EIS) were used to determine corrosion rates of iron and iron-based alloys in molten carbonate melts for both cathode and anode MCFC environments. During the initial stages, agreement among the methods was good but could have differed after a corrosion layer formed on the surface. The corrosion rate for a fully immersed sample at the open circuit potential seemed to be controlled by external mass transfer of water. Iron-chromium alloys exhibit reasonable corrosion resistance on the cathode side, provided that the chromium concentration exceeds 25%. The corrosion of bipolar plate and current collector materials in molten carbonate fuel cells (MCFC) was investigated. Tafel extrapolation, linear polarisation resistance, chronopotentiometry and electrochemical impedance spectroscopy (EIS) were used to determine corrosion rates of iron and iron-based alloys in molten carbonate melts for both cathode and anode MCFC environments. During the initial stages, agreement among the methods was good but could have differed after a corrosion layer formed on the surface. The corrosion rate for a fully immersed sample at the open circuit potential seemed to be controlled by external mass transfer of water. Iron-chromium alloys exhibit reasonable corrosion resistance on the cathode side, provided that the chromium concentration exceeds 25%.

  • 121918.
    Zhu, Baohua
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Lindbergh, Göran
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Simonsson, Daniel
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Comparison of electrochemical and surface characterisation methods for investigation of corrosion of bipolar plate materials in molten carbonate fuel cell Part II. Surface analysis1999In: Corrosion Science, Vol. 41, no 8, p. 1515-1528Article in journal (Refereed)
    Abstract [en]

    The corrosion of bipolar plate materials in molten carbonate fuel cells (MCFC) was studied by electrochemical techniques. These methods were complemented by thermogravimetric analysis (TGA) and surface analyses, such as SEM, EDX and XRD. The concentration profiles of oxygen, lithium, iron, chromium and nickel in the oxide scales were determined by means of glow discharge optical emission spectroscopy (GDOES). It has been shown that corrosion layers, formed on the iron-chromium and stainless steels surfaces, consist of two layers. The outer layer is porous and has large pores; the inner layer is more compact and may contain small pores. The corrosion of bipolar plate materials in molten carbonate fuel cells (MCFC) was studied by electrochemical techniques. These methods were complemented by thermogravimetric analysis (TGA) and surface analyses, such as SEM, EDX and XRD. The concentration profiles of oxygen, lithium, iron, chromium and nickel in the oxide scales were determined by means of glow discharge optical emission spectroscopy (GDOES). It has been shown that corrosion layers, formed on the iron-chromium and stainless steels surfaces, consist of two layers. The outer layer is porous and has large pores; the inner layer is more compact and may contain small pores.

  • 121919. Zhu, Baoyou
    et al.
    Zhou, Helin
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Thottappillil, Rajeev
    KTH, School of Electrical Engineering (EES), Electromagnetic Engineering.
    Rakov, Vladimir A.
    Simultaneous observations of electric field changes, wideband magnetic field pulses, and VHF emissions associated with K processes in lightning discharges2014In: Journal of Geophysical Research D: Atmospheres, ISSN 2169-897X, Vol. 119, no 6, p. 2699-2710Article in journal (Refereed)
    Abstract [en]

    We studied simultaneous electric field changes, microsecond-scale (VLF/LF) magnetic field pulses, and VHF emissions associated with K processes in 37 cloud and 54 cloud-to-ground lightning flashes that occurred in a local convective thunderstorm in Shanghai. All the observed features were very similar for both types of flashes. Over 98% of the 1252 observed K changes were associated with detectable microsecond-scale pulses, although only about 26% of them were accompanied by large pulses whose amplitude exceeds by at least 50% the average amplitude of the five largest pulses in the flash. VHF bursts, which almost always coincide in time with microsecond-scale pulses, can occur either during K changes or during the gaps between K changes. About 9% of K changes were observed to be associated with regular pulse trains, with pulses in the train showing one-to-one correspondence to VHF bursts and occurring at a geometric mean interval of 6.9 mu s. Overall, our results indicate that small microsecond-scale pulses are an inherent feature of K processes. We infer that the K process can be viewed as a fast negative leader, but only those leaders with appreciable charge transfer show step/ramp-like K changes in electric field records.

  • 121920.
    Zhu, Bin
    KTH, Superseded Departments, Chemical Engineering and Technology. Goeta Technol. Developer Intl, Sweden.
    Advanced ceramic fuel cell R&D2004In: Fuel Cell Science, Engineering and Technology - 2004, 2004, p. 409-417Conference paper (Refereed)
    Abstract [en]

    Since many years in Swedish national research project and Swedish-Chinese research framework we have carried out advanced ceramic fuel cell research and development, targeting for intermediate and low temperature ceramic or solid oxide fuel cells (ILTCFCs or ILTSOFCs, 300-700°C) based on ceramic-based composite materials. The ceramic composite material developments in Sweden have been experienced from the oxyacid-salts oxide proton-based conductors, non-oxide containment salts, the ceria-based composite electrolytes and nano-composites. Among them the ceria-based composites showed excellent ionic conductivity of 0.01 to 1 Scm-1 and ILTCFCs using these composites as electrolytes have achieved high performances of 200 to 1000 mWcm-2 at temperatures between 400 and 700°C. The excellent ion conduction was resulted from hybrid proton and oxygen ion conduction. The hybrid ion conduction and dual electrode reactions and processes create a new fuel cell system. Advanced ceramic fuel cell aims at developing a new generation to realize the challenges for fuel cell commercialization. This paper reviews our more than 14 years R&D on the field with emphasis on the recent progresses and achievements.

  • 121921.
    Zhu, Bin
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Advanced hybrid ion conducting ceramic composites and applications in new fuel cell generation2005In: HIGH-PERFORMANCE CERAMICS III, PTS 1 AND 2 / [ed] Pan, W; Gong, JH; Ge, CC; Li, JF, 2005, Vol. 280-283, p. 413-418Conference paper (Refereed)
    Abstract [en]

    Our developments on ceramic composite conductors have experienced about 15 years from the oxyacid-salts oxide proton-based conductors, non-oxide containment salts, the ceria-based composite electrolytes, hybrid proton and oxygen ion conductors and nano-composites. A special emphasis is paid to new functional nano-composites based on hybrid proton and oxygen ion conductors that have demonstrated advanced properties and fuel cell applications, e.g., excellent ionic conductivity of 0.01 to 1 Scm(-1) and performances of 200 - 1000 mWcm(-2) for temperatures achieved for fuel cells between 400 and 700degreesC. Some proton and oxygen ion conducting mechanisms in the materials are reviewed and discussed. The hybrid ion conduction and dual electrode reactions and processes create a new generation fuel cell system.

  • 121922.
    Zhu, Bin
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Advantages of intermediate temperature solid oxide fuel cells for tractionary applications2001In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 93, no 02-jan, p. 82-86Article in journal (Refereed)
    Abstract [en]

    Our recent achievements suggest that intermediate temperature (IT) solid oxide fuel cells (SOFCs) can become a strong competitor not only for stationary power generation, but also for tractionary applications, e.g. for electrical (hybrid) vehicles. These ITSOFCs are based on ceria-salt composite ceramic materials. These new ceria-based composite ceramic materials have shown a super ionic conductivity (0.1-1.0 S cm(-1)) in the IT region (400-600 degreesC). Using them as the electrolytes the ITSOFCs are operated between 300 and 1500 mA cm(-2) (200-700 mW cm(-2)) continuously between 400 and 600 degreesC. The opportunities and advantages of these new advanced ITSOFCs for electrical vehicle applications are discussed. The high efficiency ITSOFCs fed directly with hydrocarbon containing gas-type and liquid-type fuels have shown an enormous potential for application in electrical vehicles.

  • 121923.
    Zhu, Bin
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Applications of hydrofluoride ceramic membranes for advanced fuel cell technology2000In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 24, no 1, p. 39-49Article in journal (Refereed)
    Abstract [en]

    New types of materials, hydrofluoride-alumina ceramic composites containing one hydride component, CaH2, have been studied for fuel cell applications. Excellent fuel cell performances were achieved for a peak power density of 180 mW cm(-2) at 300 mA cm(-2), and a short-circuit current density near 1000 mA cm(-2). In fuel cell measurements the conductivity and ionic transport properties of the hydrofluoride-based electrolytes have also been investigated. During fuel cell operation, water was often observed at the cathode (air side), indicating that proton conduction occurs in these electrolyte materials. The experiments show an interesting chance for the future development of innovative fuel cell technology for commercialization.

  • 121924.
    Zhu, Bin
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Functional ceria-salt-composite materials for advanced ITSOFC applications2003In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 114, no 1, p. 1-9Article in journal (Refereed)
    Abstract [en]

    This paper reports our current material research and development for advanced intermediate temperature (IT, 400-700 degreesC) solid oxide fuel cells (SOFCs). The materials reported in this work are based on ceria-salt-composites, which have super function, e.g. displaying ionic conductivity of 0.01-1 S cm(-1) in the IT region. They are functional ceramic materials for advanced ITSOFC applications. When these new composites are used as ITSOFC electrolytes, a performance of 300-800 mW cm(-2) between 400 and 650 degreesC has been demonstrated.

  • 121925.
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Nanocomposites for Advanced Fuel Cell Technology2011In: Journal of Nanoscience and Nanotechnology, ISSN 1533-4880, Vol. 11, no 10, p. 8873-8879Article in journal (Refereed)
    Abstract [en]

    NANOCOFC (Nanocomposites for advanced fuel cell technology) is a research platform/network established based on the FP6 EC-China project www.nanocofc.org. This paper reviews major achievements on two-phase nanocomposites for advanced low temperature (300-600 degrees C) solid oxide fuel cells (SOFCs), where the ceria-salt and ceria-oxide composites are common. A typical functional nanocomposite structure is a core-shell type, in which the ceria forms a core and the salt or another oxide form the shell layer. Both of them are in the nano-scale and the functional components. The high resolution TEM analysis has proven a clear interface in the ceria-based two-phase nanocomposites. such interface and interfacial function has resulted in superionic conductivity, above 0.1 S/cm at around 300 degrees C, being comparable to that of conventional SOFC YSZ at 1000 degrees C. Against conventional material design from the structure the advanced nanocomposites are designed by non-structure factors, i.e., the interfaces, and by creating interfacial functionalities between the two constituent phases. These new functional materials show indeed a breakthrough in the SOFC materials with great potential.

  • 121926.
    Zhu, Bin
    KTH, Superseded Departments, Chemical Engineering and Technology.
    New generation or universal fuel cell system? R&D for intermediate temperature solid oxide fuel cells (ITSOFCs)2001In: Journal of New Materials for Electrochemical Systems, ISSN 1480-2422, Vol. 4, no 4, p. 239-251Article in journal (Refereed)
    Abstract [en]

    Present challenges forfuel cell (FC) commercialisation are related to the material and system limitations, delaying the FC market. Most intensive interests currently for the FCs are concentrated on the polymer electroyte fuel cells (PEFCs) and solid oxide fuel cells (SOFCs). Due to the material constraint the SOFC system has to be operated at high temperature, e.g., 1000 degreesC, resulting in expensive SOFC system and complex technology; while the noble platinum catalyst has to be used for the PEFCs, creating a bottleneck for its commercialisation. In addition, the PEFC system has limited applications due to a shortage of the fuel flexibility, e.g., for hydrocarbon fuels, existing commonly in present fuel infrastructure. There is therefore a need to develop new generation or universal FC system, which can be employed for various applications for both mobile, e.g., electrical vehicles, and stationary, e.g., power generation plant. These request an advanced FC system that should possess of the wide fuel flexibility, i.e., fitting to various present hydrocarbon fiiels, and most importantly, this FC system should be cost-effective and marketable. However the present FC systems themselves alone are difficult to meet these demands due to the, material and system limitations. Our strategy is to develop a new advanced or near universal FC system to combine technological advantage from present FC systems to create a new competitive vis-a-vis FC technology. To realise this strategy a key issue is addressed from the material point of view., This paper thus reviews recent developments/progresses and achievements/applications for R&D on the materials and ITSOFCs, more concerned on the new material-based ITSOFCs.

  • 121927.
    Zhu, Bin
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Next generation fuel cell R&D2006In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 30, no 11, p. 895-903Article in journal (Refereed)
    Abstract [en]

    The material innovations and developments can play a key role in realizing solid oxide fuel cell (SOFC) commercialization. However, it seems missing in the long SOFC R&D strategy. Recent R&D. on innovative ceria-based composites (CBCs) make a breakthrough and open a new research subject on low-temperature (300-600 degrees C) SOFCs. Low temperatures create many freedoms to develop next generation fuel cell technology for commercialization.

  • 121928.
    Zhu, Bin
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Proton and oxygen ion conduction in nonoxide ceramics2000In: Materials research bulletin, ISSN 0025-5408, E-ISSN 1873-4227, Vol. 35, no 1, p. 47-52Article in journal (Refereed)
    Abstract [en]

    By directly examining fuel cell performances, it was discovered that nonoxide containing materials such as chlorides and fluorides exhibit significant proton and oxygen ion conduction. Ionic transport measurements showed that both proton and oxygen ion conduction are present, with proton conduction predominant in most cases. Steady-state current output under fuel-cell operation indicates that the transport process in both chloride and fluoride electrolytes is dominated by the source ions, protons, and oxygen ions. These new materials have significant importance for both fundamental and applied research.

  • 121929.
    Zhu, Bin
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Proton and oxygen ion-mixed-conducting ceramic composites and fuel cells2001In: Solid State Ionics, ISSN 0167-2738, E-ISSN 1872-7689, Vol. 145, no 04-jan, p. 371-380Article in journal (Refereed)
    Abstract [en]

    This work focuses on the behaviour and role of protons and oxygen ions for the electrical properties of salt-oxide composites based on halides, more specifically on fluorides e.g. MFx (M = Li, Na. Ca, Ba, Sr, Mg. x = 1, 2)-based composites with oxides. The electrical properties were studied by using DC measurements, employing either gas concentration cell or fuel cell techniques. The conductivity of the fluoride-based composite electrolytes is 10(-3)-10(-2) S/cm at temperatures between 600 and 800 degreesC. Proton and oxygen ion defects, their generation and transport, showed a very strong dependence on the employed gas resources. Possessing both proton and oxygen ion conduction, on one hand, enhances the material total conductivity and, on the other hand, may promote the electrode reaction and the kinetics at two interfaces between the electrolyte and electrodes for fuel cells, thus, enhancing the cur-rent exchange rate and fuel cell performance. Using these composite electrolytes, a typical power density of 120-160 mW/cm(2) under a current density 300-800 mA/cm(2) was obtained in a fuel cell. Although both proton and oxygen ion conduction are possible, the proton defect concentration and related conduction generally predominate as the basic feature of the halide-based composite materials.

  • 121930.
    Zhu, Bin
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Solid oxide fuel cell (SOFC) technical challenges and solutions from nano-aspects2009In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 33, no 13, p. 1126-1137Article in journal (Refereed)
    Abstract [en]

    The classical (over 100 years) oxygen ion conductor and theory for solid oxide fuel cells (SOFCs) have met critical challenges, which are caused by the electrolyte material, the heart of the SOFC. Ionic conductivity of 0.1 S cm(-1) as a basic requirement limits conventional SOFC electrolyte material, yttrium stabilized zirconia (YSZ) functioning at ca. 1000 degrees C. Such high temperature prevents SOFC technology from commercialization. Design and development of materials functioning at low temperatures are therefore a critical challenge. State of the art of the nanotechnology remarks a great potential for SOFCs. Through a review of typical SOFC electrolyte materials and analysis of the ionic conduction theory as well as constrains and disadvantages in single-phase materials, the need for design, development and theory of new materials are obvious. Our approach is to design and develop two-phase materials and functionalities at interfaces between the constituent phases in nanotech-based composites, that is nanocomposites. The nano- and composite technologies can realize superionic conduction by constructing the interfaces as 'ion highways'. Manipulation of the interphases of the nanocomposites can overcome SOFC challenges and thus enhance and improve material conductivity and FC performance at significantly lower temperatures (300-600 degrees C).

  • 121931.
    Zhu, Bin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Albinsson, I.
    Andersson, C.
    Borsand, K.
    Nilsson, M.
    Mellander, B. E.
    Electrolysis studies based on ceria-based composites2006In: Electrochemistry communications, ISSN 1388-2481, E-ISSN 1873-1902, Vol. 8, no 3, p. 495-498Article in journal (Refereed)
    Abstract [en]

    Electrolysis behaviors have been investigated based on ceria-based composite electrolytes and fuel cells. The results showed that both proton and oxygen ion conduction exist in the ceria-based composite electrolytes resulting in high current outputs in both fuel cell and electrolysis operations. Corresponding to high current output in the electrolysis cell, a high hydrogen production can be expected. This work has first demonstrated the ceria-based composite electrolyte used for electrolysis process.

  • 121932.
    Zhu, Bin
    et al.
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Albinsson, I.
    Mellander, B. E.
    Intermediate temperature fuel cells using alkaline and alkaline earth fluoride-based electrolytes2000In: Solid State Ionics, ISSN 0167-2738, E-ISSN 1872-7689, Vol. 135, no 04-jan, p. 503-512Article in journal (Refereed)
    Abstract [en]

    Investigation of fuel cell applications using fluoride electrolytes, especially alkaline and alkaline earth fluorides, is a very new subject. Actually, most of the fluorides can function as fuel cell electrolytes, but the alkaline and alkaline earth fluorides are specially interesting since in composite materials they exhibit excellent performance for fuel cell electrolytes. Among the alkaline earth fluoride fuel cells, the best performance was achieved thus far for the fuel cell using the NaF-BaF2-Al2O3 electrolyte and LiNiO2 anode supported technique: it reached a power density of about 110 mW cm(-2) at a current density of 250 mA cm(-2) at 750 degreesC. Both proton and oxygen ionic conduction may exist in the alkaline earth fluorides since, during the fuel cell operation, water was observed at both the anode and the cathode, but, in most cases, water was formed at the cathode side mainly. Thus, proton conduction predominates, resulting in excellent fuel cell performances. A possible ionic transport mechanism is also discussed.

  • 121933.
    Zhu, Bin
    et al.
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Bai, X. Y.
    Chen, G. X.
    Yi, W. M.
    Bursell, Martin
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Fundamental study on biomass-fuelled ceramic fuel cell2002In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 26, no 1, p. 57-66Article in journal (Refereed)
    Abstract [en]

    Recent development in the advanced intermediate temperature (400 to 700degreesC) ceramic fuel cell (CFC) research brings up feasibility and new opportunity to develop innovative biomass-fuelled CFC technology. This work focuses on fundamentals of the biomass-fuelled CFCs based on available biofuel resources through thermochemical conversion technologies. Both real producer gas from biomass gasification and imitative compounded gas were used as the fuel to operate the CFCs in the biomass CFC testing station. The composition of the fuel gas was varied in a wide range of practices of the present conversion technology both in KTH and Shandong Institute of Technology (SDIT), CFC performances were achieved between 100 and 700 mW cm(-2) at 600-800degreesC corresponding to various gas compositions. A high performance close to 400 mW cm(-2) was obtained at 600degreesC for the gas with the composition of H-2 (50 per cent) + CO (15 per cent) + CO2 (15 per cent) + N-2 (20 per cent) and more than 600 mW cm(-2) for the H-2 (55 per cent) + CO (28 per cent) + CO2 (17 per cent) at 700degreesC. This paper presents the experimental results and discusses the fundamentals and future potentiality on the biomass fuelled CFCs.

  • 121934.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Hubei University, 430062, Wuhan, PR China.
    Basile, Angelo
    Tseng, Chung-Jen
    Materials as a player in hydrogen and fuel cell technologies: Preface to the special issue section2017In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 42, no 34, p. 22090-22090Article in journal (Other academic)
  • 121935.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Hubei University, China.
    Fan, L.
    Deng, H.
    He, Y.
    Afzal, Muhammad
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Dong, W.
    Yaqub, A.
    Janjua, N. K.
    LiNiFe-based layered structure oxide and composite for advanced single layer fuel cells2016In: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 316, p. 37-43Article in journal (Refereed)
    Abstract [en]

    A layered structure metal oxide, LiNi0.1Fe0.90O2-δ (LNF), is explored for the advanced single layer fuel cells (SLFCs). The temperature dependent impedance profiles and concentration cells (hydrogen concentration, oxygen concentration, and H2/air atmospheres) tests prove LNF to be an intrinsically electronic conductor in air while mixed electronic and proton conductor in H2/air environment. SLFCs constructed by pure LNF materials show significant short circuiting reflected by a low device OCV and power output (175 mW cm-2 at 500°C) due to high intrinsic electronic conduction. The power output is improved up to 640 and 760 mW cm-2, respectively at 500 and 550°C by compositing LNF with ion conducting material, e.g., samarium doped ceria (SDC), to balance the electronic and ionic conductivity; both reached at 0.1 S cm-1 level. Such an SLFC gives super-performance and simplicity over the conventional 3-layer (anode, electrolyte and cathode) FCs, suggesting strong scientific and commercial impacts.

  • 121936.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    He, Y.
    Zhao, Y.
    Wang, H.
    A commercial lithium battery LiMn-oxide for fuel cell applications2014In: Materials letters (General ed.), ISSN 0167-577X, E-ISSN 1873-4979, Vol. 126, p. 85-88Article in journal (Refereed)
    Abstract [en]

    Hereby we report first a commercial lithium battery LiMn-oxide (LMO) positive electrode material for fuel cell applications. The obtained LMO can be used for both anode and cathode in a three-layer fuel cell, but displays low electro-catalytic activity and power output. Using a nanocomposite approach we have significantly improved the cell performance from tens mW cm-2 up to 210 mW cm-2, which is technically useful for low temperature (bellow 600 °C) ceramic fuel cells. We also constructed single-layer fuel cell using the LMO/SDC-metal oxide composite and achieved even better performances than those for conventional anode-electrolyte-cathode three-layer fuel cells.

  • 121937.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Lund, Peter
    Breakthrough fuel cell technology using ceria-based multi-functional nanocomposites2013In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 106, p. 163-175Article in journal (Refereed)
    Abstract [en]

    Recent scientific and technological advancements have provided a wealth of new information about solid oxide-molten salt composite materials and multifunctional ceria-based nano-composites for advanced fuel cells (NANOCOFC). NANOCOFC is a new approach for designing and developing of multi-functionalities for nanocomposite materials, especially at 300-600 degrees C. NANOCOFC and low temperature advanced ceramic fuel cells (LTACFCs) are growing as a new promising area of research which can be explored in various ways. The ceria-based composite materials have been developed as competitive electrolyte candidates for low temperature ceramic fuel cells (LTCFCs). In the latest developments, multifunctional materials have been developed by integrating semi- and ion conductors, which have resulted in an emerging insight knowledge concerned with their R&D on single-component electrolyte-free fuel cells (EFFCs) - a breakthrough fuel cell technology. A homogenous component/layer of the semi- and ion conducting materials can realize fuel cell all functions to avoid using three components: anode, electrolyte and cathode, i.e. "three in one" highlighted by Nature Nanotechnology (2011). This report gives a short review and advance knowledge on worldwide activities on the ceria-based composites, emphasizing on the latest semi-ion conductive nanocomposites and applications for new applied energy technologies. It gives an overview to help the audience to get a comprehensive understanding on this new field.

  • 121938.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Fan, Liangdong
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Zhao, Yufeng
    Tan, Wenyi
    Xiong, Dingbang
    Wang, Hao
    Functional semiconductor-ionic composite GDC-KZnAl/LiNiCuZnOx for single-component fuel cell2014In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 4, no 20, p. 9920-9925Article in journal (Refereed)
    Abstract [en]

    The research activities on single-component fuel cells (SCFCs) have opened new doors for keeping ahead with two major areas of focus: improvement of SCFC performances by contributing new materials, and scientific understanding of the SCFC nature and operation mode. The present work reports the exploitation of new material composed of the Gd doped ceria-KAlZn-oxide (GDC-KAZ) and the LiNiCuZn-oxide (LNCZ), combining ionic and semiconducting properties for SCFCs. A new method is first used through an internal electron-hole redox cycle resulting in no net electrons to avoid ceria electronic conduction problems thus to develop an excellent GDC-KAZ electrolyte. Its ionic conductivity, 0.08 S cm(-1) at 600 degrees C, is ten times higher than that of GDC. The SCFC using the GDC-KAZ-LNCZ materials exhibits a remarkable electrochemical performance of 628 mW cm(-2) at 580 degrees C, significantly higher than that of conventional three-component (anode/electrolyte/cathode) fuel cells. The results bring about a new cost-effective and robust system with significant scientific and economic consequences for the fuel cell field.

  • 121939.
    Zhu, Bin
    et al.
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Fu, Q. X.
    Meng, G. Y.
    Jurado, J. F.
    Albinsson, I.
    Mellander, B. E.
    LiF-MgF2 composite electrolyte for advanced ceramic fuel cells: structure, electrical properties and applications2002In: Solid State Ionics, ISSN 0167-2738, E-ISSN 1872-7689, Vol. 148, no 04-mar, p. 583-589Article in journal (Refereed)
    Abstract [en]

    The two-phase composite, LiF-MgF2, has been discovered to have high ionic conductivity within a wide composition range, e.g., 10(-2)-10(-1) S cm(-1) at 600-800 degreesC, which is several orders of magnitude higher than that of pure LiF or MgF2. In addition, the activation energy of the composite is much lower than that of the pure phases. The remarkable conductivity enhancement as well as the low activation energy is attributed to the composite effect, i.e., the conduction takes place mainly in the interfacial region between LiF and MgF2 grains. The agreements of conductivity derived from two different methods, impedance spectra and fuel cell characterisation, in combination of the ESR results, show a possibility that proton (plus hydride ion) conduction dominates the electrical conduction in the LiF-MgF2 system under the H-2/air fuel cell environments.

  • 121940.
    Zhu, Bin
    et al.
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID. China Academy of Art, China.
    Hedman, Anders
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID.
    Feng, Shuo
    KTH, School of Computer Science and Communication (CSC).
    Li, Haibo
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID.
    Osika, Walter
    Designing, Prototyping and Evaluating Digital Mindfulness Applications: A Case Study of Mindful Breathing for Stress Reduction2017In: Journal of Medical Internet Research, ISSN 1438-8871, E-ISSN 1438-8871, Vol. 19, no 6, article id e197Article in journal (Refereed)
    Abstract [en]

    Background: During the past decade, there has been a rapid increase of interactive apps designed for health and well-being. Yet, little research has been published on developing frameworks for design and evaluation of digital mindfulness facilitating technologies. Moreover, many existing digital mindfulness applications are purely software based. There is room for further exploration and assessment of designs that make more use of physical qualities of artifacts. Objective: The study aimed to develop and test a new physical digital mindfulness prototype designed for stress reduction. Methods: In this case study, we designed, developed, and evaluated HU, a physical digital mindfulness prototype designed for stress reduction. In the first phase, we used vapor and light to support mindful breathing and invited 25 participants through snowball sampling to test HU. In the second phase, we added sonification. We deployed a package of probes such as photos, diaries, and cards to collect data from users who explored HU in their homes. Thereafter, we evaluated our installation using both self-assessed stress levels and heart rate (HR) and heart rate variability (HRV) measures in a pilot study, in order to measure stress resilience effects. After the experiment, we performed a semistructured interview to reflect on HU and investigate the design of digital mindfulness apps for stress reduction. Results: The results of the first phase showed that 22 of 25 participants (88%) claimed vapor and light could be effective ways of promoting mindful breathing. Vapor could potentially support mindful breathing better than light (especially for mindfulness beginners). In addition, a majority of the participants mentioned sound as an alternative medium. In the second phase, we found that participants thought that HU could work well for stress reduction. We compared the effect of silent HU (using light and vapor without sound) and sonified HU on 5 participants. Subjective stress levels were statistically improved with both silent and sonified HU. The mean value of HR using silent HU was significantly lower than resting baseline and sonified HU. The mean value of root mean square of differences (RMSSD) using silent HU was significantly higher than resting baseline. We found that the differences between our objective and subjective assessments were intriguing and prompted us to investigate them further. Conclusions: Our evaluation of HU indicated that HU could facilitate relaxed breathing and stress reduction. There was a difference in outcome between the physiological measures of stress and the subjective reports of stress, as well as a large intervariability among study participants. Our conclusion is that the use of stress reduction tools should be customized and that the design work of mindfulness technology for stress reduction is a complex process, which requires cooperation of designers, HCI (Human-Computer Interaction) experts and clinicians.

  • 121941.
    Zhu, Bin
    et al.
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID. China Acad Art, Hangzhou, Zhejiang, Peoples R China..
    Hedman, Anders
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID.
    Li, Haibo
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID.
    Designing Digital Mindfulness: Presence-In and Presence-With versus Presence-Through2017In: PROCEEDINGS OF THE 2017 ACM SIGCHI CONFERENCE ON HUMAN FACTORS IN COMPUTING SYSTEMS (CHI'17), ASSOC COMPUTING MACHINERY , 2017, p. 2685-2695Conference paper (Refereed)
    Abstract [en]

    The digital health and wellbeing movement has led to development of digital mindfulness applications that aim to help people to become mindful. In this paper we suggest a broad scheme for classifying and ordering apps intended to support mindfulness. This scheme consists of four levels of what we here term digital mindfulness. One crucial aspect of the fourth level is that artifacts at this level allow for what we term as presence-with and presence-in as opposed to presence-through, which occurs at the first three levels. We articulate our four levels along with specific design qualities through concrete examples of existing mindfulness apps and through research through design (RtD) work conducted with design fiction examples. We then use a working design case prototype to further illustrate the possibilities of presence-with and presence-in. We hope our four levels of digital mindfulness framework will be found useful by other researchers in discussing and planning the design of their own mindfulness apps and digital artifacts.

  • 121942.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology. Faculty of Physics and Electronic Science, Hubei University, Wuhan, Hubei, China.
    Huang, Yizhong
    Fan, L.
    Ma, Y.
    Wang, Baoyuan
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Faculty of Physics and Electronic Science, Hubei University, Wuhan, Hubei, China.
    Xia, Chen
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Afzal, Muhammad
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Zhang, B.
    Dong, W.
    Wang, H.
    Lund, P. D.
    Novel fuel cell with nanocomposite functional layer designed by perovskite solar cell principle2016In: Nano Energy, ISSN 2211-2855, Vol. 19, p. 156-164Article in journal (Refereed)
    Abstract [en]

    A novel fuel-to-electricity conversion technology resembling a fuel cell has been developed based on the perovskite solar cell principle using a perovskite, e.g. La0.6Sr0.4Co0.2Fe0.8O3-δ and an ionic nanocomposite material as a core functional layer, sandwiched between n- and p-conducting layers. The conversion process makes use of semiconductor energy bands and junctions properties. The physical properties of the junction and alignment of the semiconductor energy band allow for direct ion transport and prevent internal electronic short-circuiting, while at the same time avoiding losses at distinct electrolyte/electrode interfaces typical to conventional fuel cells. The new device achieved a stable power output of 1080mWcm-2 at 550°C in converting hydrogen fuel into electricity.

  • 121943.
    Zhu, Bin
    et al.
    KTH.
    Kürth-Landwehr, S.
    Corbi, Victor Guerrero
    KTH.
    YU: An artistic exploration of interface design for home healthcare2014In: TEI '14 Proceedings of the 8th International Conference on Tangible, Embedded and Embodied Interaction, 2014, p. 332-334Conference paper (Refereed)
    Abstract [en]

    YU is an artistic home healthcare system including measuring, visualizing and displaying personal bio-data as well as biofeedback. It integrates with the home setting and aims for bringing aesthetic experience. Through the system YU, we explore possibilities of design health technologies with artistic interface into our home life. Instead of commonly used numeric or graphical interface, we use Chinese ink painting to visualize the pulse and HRV (Heart Rate Variability). We design an artistic interface with two display modes and three levels of interactivity involving in the home life.

  • 121944.
    Zhu, Bin
    et al.
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID. Hubei Univ.
    Li, Haibo
    KTH, School of Computer Science and Communication (CSC), Media Technology and Interaction Design, MID.
    Designing finger movement on mobile phone touch screen for rich emotional expression2014In: 2014 Asia-Pacific Signal and Information Processing Association Annual Summit and Conference, APSIPA 2014, IEEE conference proceedings, 2014Conference paper (Refereed)
    Abstract [en]

    Emotional expression is significant as an essential part in our daily life. Ubiquitous presence of mobile technology-mediated communication creates various affective occasions and affords rich emotional expressions with lower complexity of input. In this paper, we aim to design a simple way of emotional expression through finger movements on mobile phone touch screen allowing for richer affective expressivities. We categorize the visual representations into four types according to their modality and then raised a schema that including three core properties of touch-screen based finger movement dynamics. From design practice, we find the form and property of visual representation shapes the experience of expression and the way finger moves. Kinesthetic representation with its dynamic property can reflect the core properties of finger movement and thus afford the rich expressivity in presenting emotional experience. Thus, we indicate that simple finger movements based on mobile phone touch screens can express rich emotional experience. Moreover, we suggest designing appropriate and corresponding properties of visual representation regarding to the properties of finger movement as a meaningful and expressive material. © 2014 Asia-Pacific Signal and Information Processing Ass.

  • 121945.
    Zhu, Bin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Li, S.
    Mellander, B. E.
    Theoretical approach on ceria-based two-phase electrolytes for low temperature (300-600 degrees C) solid oxide fuel cells2008In: Electrochemistry communications, ISSN 1388-2481, E-ISSN 1873-1902, Vol. 10, no 2, p. 302-305Article in journal (Refereed)
    Abstract [en]

    Recently, extensive studies on the ceria-based two-phase composites as functional electrolytes have created excellent 300-600 degrees C fuel cell technology. There is an emergence need to deepen the knowledge and to develop theoretical methodologies in this field. The feasibility to design and develop two-phase materials as superionic conductors for 300-600 degrees C solid oxide fuel cells (LTSOFCs) is reported. The superionic conductivity at 300-600 degrees C in two-phase materials where the interfaces between the constituent phases are constructed as "superionic highways" resulting in interfacial high ionic conduction. The material architecture and design presented in this report thus reaches beyond the conventional molecular way to synthesize new compounds.

  • 121946.
    Zhu, Bin
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Li, S.
    Sun, X. L.
    Sun, J. C.
    Fuel Cell and Electrolysis Studies with Dual Phase Proton and Oxide Ion Conduction2012In: Molten Salts and Ionic Liquids: Never the Twain?, John Wiley & Sons, 2012, p. 407-417Chapter in book (Refereed)
  • 121947. Zhu, Bin
    et al.
    Lindquist, Anders
    KTH.
    An Identification Approach to Image Deblurring2016In: PROCEEDINGS OF THE 35TH CHINESE CONTROL CONFERENCE 2016 / [ed] Chen, J Zhao, Q, IEEE Computer Society, 2016, p. 235-241Conference paper (Refereed)
    Abstract [en]

    In this paper we present a new method of reconstructing an image that undergoes a spatially invariant blurring process and is corrupted by noise. The methodology is based on a theory of multidimensional moment problems with rationality constraints. This can be seen as generalized spectral estimation with a finiteness condition, which in turn can be considered a problem in system identification. With noise it becomes an ill-posed deconvolution problem and needs regularization. A Newton solver is developed, and the algorithm is tested on two images under different boundary conditions. These preliminary results show that the proposed method could be a viable alternative to regularized least squares for image deblurring, although more work is needed to perfect the method.

  • 121948.
    Zhu, Bin
    et al.
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Liu, X. G.
    Sun, M. T.
    Ji, S. J.
    Sun, J. C.
    Calcium doped ceria-based materials for cost-effective intermediate temperature solid oxide fuel cells2003In: Solid State Sciences, ISSN 1293-2558, E-ISSN 1873-3085, Vol. 5, no 8, p. 1127-1134Article in journal (Refereed)
    Abstract [en]

    This paper studies preparation and characterization of the calcium doping ceria (CCO) and carbonate composite materials. The material preparation was performed based on an oxalate co-precipitation. Various material characterizations were carried on the material phase structure based on XRD, TG/DSC and their fuel cell applications. The CCO materials showed a two-phase composite with very high ionic conductivity, 0.01 to 0.5 S cm(-1) between 400 and 700degreesC. Using the CCO-composites as the electrolytes for intermediate temperature solid oxide fuel cells (ITSOFC) a high performance, e.g., 600 mW cm(-2) was demonstrated at 600degreesC.

  • 121949.
    Zhu, Bin
    et al.
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Liu, X. G.
    Zhou, P.
    Yang, X. T.
    Zhu, Z. G.
    Zhu, W.
    Innovative solid carbonate-ceria composite electrolyte fuel cells2001In: Electrochemistry communications, ISSN 1388-2481, E-ISSN 1873-1902, Vol. 3, no 10, p. 566-571Article in journal (Refereed)
    Abstract [en]

    An innovative solid carbonate-oxide composite and related fuel cell (FC) technology is reported, It was discovered that solid carbonate-ceria composite (SCC) electrolytes were highly conductive with the material conductivity level varying from 0.001 to 0.2 S cm(-1) between 400 and 600 degreesC, and related FCs reached a power density between 200 and 600 mW cm(2) at a Current density of 300-1200 mA cm(-2) in the same temperature region. The SCCs were discovered to possess both oxide-ion (originating from the ceria phase) and proton (from the carbonate phase) conduction. Being an all-solid ceramic FC. the SCC can effectively reduce the material corrosion problem that is serious for the molten carbonate fuel cells (MCFCs). On the other hand, the innovative FC technology based on the SCC electrolytes developed in this work is similar to solid oxide fuel cells (SOF'Cs) and different from the MCFCs based on their ionic transport and FC processes, which facilitates a development of new type of advanced FC technology.

  • 121950.
    Zhu, Bin
    et al.
    KTH, Superseded Departments, Chemical Engineering and Technology.
    Liu, X. R.
    LiF-CaH2 alumina electrolytes for intermediate temperature fuel cell applications2000In: Electrochemistry communications, ISSN 1388-2481, E-ISSN 1873-1902, Vol. 2, no 1, p. 10-14Article in journal (Refereed)
    Abstract [en]

    Hydrofluoride-based electrolytes with proton conduction have been successfully used in intermediate: temperature fuel cell applications. Among the various hydrofluoride electrolytes, LiF-CaH2 and its composite with Al2O3, i.e., LiF-CaH2-Al2O3, are the most promising candidates which show more advantages than the other hydrofluorides. In this communication, we put our emphasis on the LiF-CaH2-Al2O3 electrolytes and their applications for intermediate temperature fuel cells. Furthermore, new fuel cell processes from hydride ions, H-, and the electrochemical behaviour of LiF-CaH2-Al2O3 electrolytes and fuel cells are discussed in more detail.

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