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  • 1. A. Hosseini, V.
    et al.
    Karlsson, L.
    Örnek, Cem
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. Swerea KIMAB AB.
    Reccagni, P.
    Wessman, S.
    Engelberg, D.
    Microstructure and functionality of a uniquely graded super duplex stainless steel designed by a novel arc heat treatment method2018In: Materials Characterization, ISSN 1044-5803, E-ISSN 1873-4189, Vol. 139, p. 390-400Article in journal (Refereed)
    Abstract [en]

    A novel arc heat treatment technique was applied to design a uniquely graded super duplex stainless steel (SDSS), by subjecting a single sample to a steady state temperature gradient for 10 h. A new experimental approach was used to map precipitation in microstructure, covering aging temperatures of up to 1430 °C. The microstructure was characterized and functionality was evaluated via hardness mapping. Nitrogen depletion adjacent to the fusion boundary depressed the upper temperature limit for austenite formation and influenced the phase balance above 980 °C. Austenite/ferrite boundaries deviating from Kurdjumov–Sachs orientation relationship (OR) were preferred locations for precipitation of σ at 630–1000 °C, χ at 560–1000 °C, Cr2N at 600–900 °C and R between 550 °C and 700 °C. Precipitate morphology changed with decreasing temperature; from blocky to coral-shaped for σ, from discrete blocky to elongated particles for χ, and from polygonal to disc-shaped for R. Thermodynamic calculations of phase equilibria largely agreed with observations above 750 °C when considering nitrogen loss. Formation of intermetallic phases and 475 °C-embrittlement resulted in increased hardness. A schematic diagram, correlating information about phase contents, morphologies and hardness, as a function of exposure temperature, is introduced for evaluation of functionality of microstructures.

  • 2.
    Abbadessa, Anna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Oinonen, Petri
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Ecohelix AB, Teknikringen 38, SE-10044 Stockholm, Sweden..
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Characterization of Two Novel Bio-based Materials from Pulping Process Side Streams: Ecohelix and CleanFlow Black Lignin2018In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 13, no 4, p. 7606-7627Article in journal (Refereed)
    Abstract [en]

    The characteristics of two novel types of technical lignin, namely Ecohelix (EH) and CleanFlow black lignin (CFBL), isolated from two different pulping process side streams, were analyzed. EH and CFBL were analyzed in terms of general composition, chemical functionalities, molar mass distribution, and thermal stability. For comparison, two relevant types of commercially available lignosulfonate and kraft lignin were used. The results showed that EH contains a large amount of sulfonated lignin, together with carbohydrates and ash. As such, it can be considered a lignin-carbohydrate hybrid molecule. CFBL was found to contain 91.5% Klason lignin and the lowest amount of carbohydrates (0.3%). EH showed the highest content of aliphatic OH groups (5.44 mmol/g) and CFBL a high content of phenols (4.73 mmol/g). EH had a molecular weight of 31.4 kDa and a sufficient thermal stability. CFBL had the lowest molecular weight (M-w = 2.0 kDa) and thermal stability of all kraft lignins analyzed in this study. These properties highlighted that EH is a suitable building block for material development and that CFBL is a promising material for the production of biofuel and biochemicals.

  • 3.
    Abbasi, M.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Backstrom, J.
    Mid Sweden Univ, FSCN Mat Phys, Dept Nat Sci, SE-85170 Sundsvall, Sweden..
    Cornell, Ann M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Fabrication of Spin-Coated Ti/TiHx/Ni-Sb-SnO2 Electrode: Stability and Electrocatalytic Activity2018In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 165, no 9, p. H568-H574Article in journal (Refereed)
    Abstract [en]

    A novel three-layer anode having the composition Ti/TiHx/Ni-Sb-SnO2 (Ti/TiHx/NATO) was successfully prepared by a spin-coating and pyrolysis process aiming at a long service lifetime and good electrocatalytic properties for ozone formation. The TiHx as an interlayer was produced by electrochemical cathodic reduction of a coated layer of the TiOx on the titanium substrate. Spin coating and thermal decomposition were used to deposit the Sn-Sb-Ni precursor on the surface of the prepared Ti/TiHx electrode. Cyclic and linear scanning voltammetry, Raman spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to reveal the electrode performance and morphology. Results show that the onset potential for the oxygen evolution reaction (OER) of Ti/TiHx /NATO is higher than for Ti/NATO. They also indicate that the service lifetime of the Ti/TiHx/NATO is twice as long as the Ti/NATO at a current density of 50 mA.cm(-2) at room temperature. Electrochemical ozone generation and degradation of the methylene blue were investigated to confirm selectivity and activity of the electrodes. After 5 min electrolysis, a current efficiency for ozone generation of 56% was obtained the electrode with TiHx while 38% was obtained on Ti/NATO under same conditions. The results also confirm that the Ti/TiH x /NATO has a higher kinetic rate constant and decolorization efficiency for removal of the methylene blue compare to the Ti/NATO. The rate constant for the pseudo-first ordered reaction of methylene blue degradation showed high values of 350 x 10(-3) min(-1) for Ti/NATO and 440 x 10(-3) min(-1) for Ti/TiHx/NATO. 

  • 4.
    Abdel Alim, Richard
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Formation of Soft Particles in Drop-in Fuels2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As the mission to the decrease global warming and phase out highly pollutingenvironmental practices globally, regulations including Euro 6 and policies generated by theUnited Nations Framework Convention on Climate Change (UNFCCC) are pushing companiesto be more innovative when it comes to their energy sources. These regulations involve manyfactors related to the cleanliness of the fuel and produced emissions, for example, propertiesof the fuels such as sulfur content, ash content, water content, and resulting emission valuesof Carbon dioxide (CO2) and Nitrogen Oxides (NOx). Furthermore, Sweden has set achallenging target of a fossil-fuel-independent vehicle fleet by 2030 and no net greenhousegasemissions by 2050.One way to cut down on the polluting properties in the fuel, as well as weakening thedependence on fossil fuel based fuel includes utilizing higher blending ratios of biofuels in thetransport sector. This transition to biofuels comes with many challenges to the transportindustry due to higher concentrations of these new fuels leads to clogging of the filters in theengine, as well as, internal diesel injector deposits (IDIDs) that produce injector fouling. Thisclogging of the filters leads to lower performance by the engines which leads to higher repairtimes (uptime) and less time on the road to transport goods. The formation of these softparticles at the root of the clogging issue is a pivotal issue because the precise mechanismsbehind their formation are highly unknown. Scania, a leader in the Swedish automotiveindustry, is very interested in figuring out what mechanisms are the most influential in theformation of these particles in the engine. Understanding the key mechanisms would allowScania to make appropriate adjustments to the fuel or the engines to ensure more time onthe road and less maintenance.There are many conditions known to be possible causes of the formation of softparticles in engines such as water content, ash content, and temperature. After generatingsoft particles using a modified accelerated method, particles were analyzed using infraredtechnology (RTX-FTIR) and a Scanning Electric Microscope (SEM-EDX). Many differentexperiments were performed to be able to make a conclusion as to which mechanisms weremost influential including temperature, time, water, air, and oil. The combination of agingbiofuels (B100, B10, HVO) with metals, and water produced the largest amount of particlesfollowed by aging the biofuels with aged oil, metals, and water. Aging the fuels with aged oilincreased particles, meanwhile the addition of water prevented particle production possiblydue to additives. B100 produced the highest amount of particles when aged with Copper, B10with Brass, and HVO with Iron.

  • 5.
    Abdelhamid, Hani Nasser
    et al.
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden.;Assiut Univ, Dept Chem, Adv Multifunct Mat Lab, Assiut 71515, Egypt..
    El-Zohry, Ahmed M.
    Uppsala Univ, Dept Chem, Angstrom Labs, POB 523, S-75120 Uppsala, Sweden..
    Cong, Jiayan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Thersleff, Thomas
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Karlsson, Karl Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Kloo, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Zou, Xiaodong
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Towards implementing hierarchical porous zeolitic imidazolate frameworks in dye-sensitized solar cells2019In: Royal Society Open Science, E-ISSN 2054-5703, Vol. 6, no 7, article id 190723Article in journal (Refereed)
    Abstract [en]

    A one-pot method for encapsulation of dye, which can be applied for dye-sensitized solar cells (DSSCs), and synthesis of hierarchical porous zeolitic imidazolate frameworks (ZIF-8), is reported. The size of the encapsulated dye tunes the mesoporosity and surface area of ZIF-8. The mesopore size, Langmuir surface area and pore volume are 15 nm, 960-1500 m(2). g(-1) and 0.36-0.61 cm(3). g(-1), respectively. After encapsulation into ZIF-8, the dyes show longer emission lifetimes (greater than 4-8-fold) as compared to the corresponding non-encapsulated dyes, due to suppression of aggregation, and torsional motions.

  • 6.
    Abdel-Magied, Ahmed F.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Nasser Abdelhamid, Hani
    Ashour, Radwa M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Zou, Xiaodong
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Hierarchical porous zeolitic imidazolate framework nanoparticles for efficient adsorption of rare-earth elements2019In: Microporous and Mesoporous Materials, ISSN 1387-1811, E-ISSN 1873-3093, Vol. 278, p. 175-184Article in journal (Refereed)
    Abstract [en]

    Hierarchical porous zeolitic imidazolate frameworks nanoparticles (ZIF-8 NPs) were synthesized at room temperature via a template-free approach under dynamic conditions (stirring) using water as a solvent. The ZIF-8 NPs were evaluated as adsorbents for rare earth elements (La3+, Sm3+ and Dy3+). Adsorption equilibrium was reached after 7h and high adsorption capacities were obtained for dysprosium and samarium (430.4 and 281.1 mg g(-1), respectively) and moderate adsorption capacity for lanthanum (28.8 mg g(-1)) at a pH of 7.0. The high adsorption capacitiese, as well as the high stability of ZIF-8 NPs, make the hierarchical ZIF-8 materials as an efficient adsorbent for the recovery of La3+, Sm3+ and Dy3+ from aqueous solution.

  • 7.
    Abdi Yusuf Isse, Muna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Identifying Patient Safety and The Healthcare Environment in Puntland, Somalia2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Independent on where in the world one is, patient safety is regarded as one of the most important aspects in the healthcare industry. On the contrary, depending on where you are, the patient safety will differ and is therefore location dependent. The patient safety in a developing country will therefore be evaluated in a different way compared to a developed country. This study, therefore aimed to identify the patient safety in Puntland, Somalia and with it, its healthcare environment in the hospitals. The goal was to identify the main factors that affected the patient safety.

    To investigate this, a field study to the region of interest was made and subsequently interviews with staff at the site were conducted as well as observations in the concerned hospitals. The obtained results were analysed using the method of Qualitative Content Analysis. At a later stage, the results could be thematized into four categories; “​Need​”, “​Device​”, “​Training​” and “​Knowledge​”, which pinpointed the main issues.

    The study show that there was a common transversal issue of a inherent lack of devices, training and knowledge which in turn could severely affect the patients and their safety in ways such as misdiagnosis, delayed treatment and in worst cases death. Furthermore, it was evident that rather than the lack of actual devices, the absence of knowledge was more prevalent. 

  • 8.
    Abdirahman Ahmed, Fatima
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Reologistudie av vattenbaserade industrifärger2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The rheological properties of water-based paint have been studied and the parameters that were investigated were mobility, viscoelasticity, sagging and levelling. The methods that arepresented in this study can predict sagging before the paint is applied on a vertical surface. The purpose of this study is to understand how different paints behave when sprayed on a vertical surface. The main goal in this study is to develop a method that can predict sagging when the wet condition is 300 μm.

    The rheometer gave measurement data that could be graded on a scale. Every paint had a value on this graded scale. A "Shear Rate Loop Test" was used to grade the paints after a graphical analysis. The development on the graded scale gives the right information whether the paint sags or not.

    Different types of oscillation tests were performed and these tests were 3ITT, amplitude sweep and frequency sweep. Elastic and viscous behaviour were measured and they illustrated what behaviour was dominating in the paints. 28 water-based paints were analysed and the methods for these paints can predict how they flow on a vertical surface.

  • 9.
    Abdirahman, Khalid
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Förnberg, Sebastian
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Styrsystem för solcellsladdade batterier2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of solar cells is continuously increasing in Sweden and the powergenerated by the solar cells is usually stored in lead acid batteries. These batterieshave a bad impact on the environment as much energy and environmentallyhazardous materials like lead and sulfuric acid are required to manufacture thesebatteries. Östersjökompaniet AB and many of its customers realize the importanceof sustainable thinking and were interested in knowing if it was possible tomaximize the lifetime of these batteries. During the course of the work, differentmethods of battery charging and discharging were analyzed that could affect thebatteries lifetime and how to take care of them to optimize them. A chargecontroller was used to optimize the charge of the battery. To calculate theremaining state of charge in the battery, the Extended voltmeter method was used.A prototype that was able to charge the batteries optimally, warn when the batterycapacity became too low, and a user-friendly application for battery monitoring wasdesigned. The calculated lifetime of a battery is not an exact science. According tostudies the lifetime of a battery can be doubled if it is c

  • 10.
    Abellan-Flos, Marta
    et al.
    Univ Namur, Dept Chim, Lab Chim Bioorgan, Rue Bruxelles 61, B-5000 Namur, Belgium.;PSL Univ, CNRS, ESPCI Paris, Mol Macromol Chem & Mat, 10 Rue Vauquelin, F-75005 Paris, France..
    Timmer, Brian J. J.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Altun, Samuel
    Attana AB, Bjornnasvagen 21, S-11419 Stockholm, Sweden..
    Aastrup, Teodor
    Attana AB, Bjornnasvagen 21, S-11419 Stockholm, Sweden..
    Vincent, Stephane P.
    Univ Namur, Dept Chim, Lab Chim Bioorgan, Rue Bruxelles 61, B-5000 Namur, Belgium..
    Ramström, Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. Univ Massachusetts, Dept Chem, One Univ Ave, Lowell, MA 01854 USA.;Linnaeus Univ, Dept Chem & Biomed Sci, SE-39182 Kalmar, Sweden..
    QCM sensing of multivalent interactions between lectins and well-defined glycosylated nanoplatforms2019In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 139, article id 111328Article in journal (Refereed)
    Abstract [en]

    Quartz crystal microbalance (QCM) methodology has been adopted to unravel important factors contributing to the "cluster glycoside effect" observed in carbohydrate-lectin interactions. Well-defined, glycosylated nanostructures of precise sizes, geometries and functionalization patterns were designed and synthesized, and applied to analysis of the interaction kinetics and thermodynamics with immobilized lectins. The nanostructures were based on Borromean rings, dodecaamine cages, and fullerenes, each of which carrying a defined number of carbohydrate ligands at precise locations. The synthesis of the Borromeates and dodecaamine cages was easily adjustable due to the modular assembly of the structures, resulting in variations in presentation mode. The binding properties of the glycosylated nanoplatforms were evaluated using flow-through QCM technology, as well as hemagglutination inhibition assays, and compared with dodecaglycosylated fullerenes and a monovalent reference. With the QCM setup, the association and dissociation rate constants and the associated equilibrium constants of the interactions could be estimated, and the results used to delineate the multivalency effects of the lectin-nanostructure interactions.

  • 11.
    Abraham, Johannes
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Romano, Robin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Automatisk kvalitetssäkring av information för järnvägsanläggningar: Automatic quality assurance of information for railway infrastructure2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With increased expectations for the expansion of the future railway, this entails an increased load on the current railway network. The result of the expansion can be an increasing number of cancellations and delays. By taking advantage of technological innovations such as digitalization and automation, the existing system and work  processes can be developed for more efficient management.   The Swedish Transport Administration sets requirements for Building Information Modeling (BIM) in procurements. The planning of signal installations within the railway takes place in Sweco using the CAD program Promis.e. From the program, lists containing the information of the objects (BIS-lists) can be retrieved. The  Swedish Transport Administration requires that the attributes must consist of a  certain format or have specific values. In this thesis project, methods for automatic quality assurance of infrastructure information and the implementation of the method for rail projects were examined. The investigated methods include the  calculation program Excel, the query programming language SQL and the process of ETL.  After analyzing the methods, the ETL process was chosen. The result was that a  program was created to automatically select the type of BIS list that would be  reviewed and to verify that the examined attributes contained allowed values. In  order to investigate whether the cost of the programs would benefit the company in addition to the quality assurance, an economic analysis was carried out. According to the calculations, the choice of method could also be justified from an economic  perspective.

  • 12.
    Abreu, Barbara
    et al.
    Univ Porto, Fac Sci, Dept Chem & Biochem, CIQUP, Rua Campo Alegre, P-4169007 Porto, Portugal..
    Rocha, Jessica
    Univ Porto, Fac Sci, Dept Chem & Biochem, CIQUP, Rua Campo Alegre, P-4169007 Porto, Portugal..
    Ferreira Fernandes, Ricardo Manuel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Regev, Oren
    Ben Gurion Univ Negev, Dept Chem Engn, IL-84105 Beer Sheva, Israel.;Ben Gurion Univ Negev, Ilse Katz Inst Nanotechnol, IL-84105 Beer Sheva, Israel..
    Furo, Istvan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Applied Physical Chemistry.
    Marques, Eduardo F.
    Univ Porto, Fac Sci, Dept Chem & Biochem, CIQUP, Rua Campo Alegre, P-4169007 Porto, Portugal..
    Gemini surfactants as efficient dispersants of multiwalled carbon nanotubes: Interplay of molecular parameters on nanotube dispersibility and debundling2019In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 547, p. 69-77Article in journal (Refereed)
    Abstract [en]

    Surfactants have been widely employed to debundle, disperse and stabilize carbon nanotubes in aqueous solvents. Yet, a thorough understanding of the dispersing mechanisms at molecular level is still warranted. Herein, we investigated the influence of the molecular structure of gemini surfactants on the dispersibility of multiwalled carbon nanotubes (MWNTs). We used dicationic n-s-n gemini surfactants, varying n and s, the number of alkyl tail and alkyl spacer carbons, respectively; for comparisons, single-tailed surfactant homologues were also studied. Detailed curves of dispersed MWNT concentration vs. surfactant concentration were obtained through a stringently controlled experimental procedure, allowing for molecular insight. The gemini are found to be much more efficient dispersants than their single-tailed homologues, i.e. lower surfactant concentration is needed to attain the maximum dispersed MWNT concentration. In general, the spacer length has a comparatively higher influence on the dispersing efficiency than the tail length. Further, scanning electron microscopy imaging shows a sizeable degree of MWNT debundling by the gemini surfactants in the obtained dispersions. Our observations also point to an adsorption process that does not entail the formation of micelle-like aggregates on the nanotube surface, but rather coverage by individual molecules, among which the ones that seem to be able to adapt best to the nanotube surface provide the highest efficiency. These studies are relevant for the rational design and choice of optimal dispersants for carbon nanomaterials and other similarly water-insoluble materials.

  • 13. Abtahi, Farhad
    et al.
    Forsman, Mikael
    Diaz-Olivazrez, Jose A.
    KTH, School of Technology and Health (STH).
    Yang, Liyun
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Lu, Ke
    KTH, School of Technology and Health (STH).
    Eklund, Jörgen
    KTH, School of Technology and Health (STH).
    Lindecrantz, Kaj
    KTH, School of Technology and Health (STH).
    Seoane, Fernando
    Teriö, Heikki
    Mediavilla Martinez, Cesar
    Aso, Santiago
    Tiemann, Christian
    Big Data & Wearable Sensors Ensuring Safety and Health @Work2017In: GLOBAL HEALTH 2017, The Sixth International Conference on Global Health Challenges, 2017Conference paper (Refereed)
    Abstract [en]

    —Work-related injuries and disorders constitute a major burden and cost for employers, society in general and workers in particular. We@Work is a project that aims to develop an integrated solution for promoting and supporting a safe and healthy working life by combining wearable technologies, Big Data analytics, ergonomics, and information and communication technologies. The We@Work solution aims to support the worker and employer to ensure a healthy working life through pervasive monitoring for early warnings, prompt detection of capacity-loss and accurate risk assessments at workplace as well as self-management of a healthy working life. A multiservice platform will allow unobtrusive data collection at workplaces. Big Data analytics will provide real-time information useful to prevent work injuries and support healthy working life

  • 14.
    Abtahi, Farhad
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics. Karolinska Inst, Inst Environm Med, S-17165 Stockholm, Sweden..
    Lu, Ke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Diaz-Olivares, Jose A.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Forsman, Mikael
    Karolinska Inst, Inst Environm Med, S-17165 Stockholm, Sweden..
    Seoane, Fernando
    Karolinska Inst, Dept Clin Sci Intervent & Technol, Halsovagen 7, S-14157 Stockholm, Sweden.;Univ Boras, Swedish Sch Text, Allegatan 1, S-50190 Boras, Sweden.;Karolinska Univ Hosp, Dept Biomed Engn, S-17176 Solna, Sweden..
    Lindecrantz, Kaj
    Karolinska Inst, Inst Environm Med, S-17165 Stockholm, Sweden.;Univ Boras, Sci Pk,Allegatan 1, S-50190 Boras, Sweden..
    Wearable Sensors Enabling Personalized Occupational Healthcare2018In: INTELLIGENT ENVIRONMENTS 2018 / [ed] Chatzigiannakis, I Tobe, Y Novais, P Amft, O, IOS PRESS , 2018, p. 371-376Conference paper (Refereed)
    Abstract [en]

    This paper presents needs and potentials for wearable sensors in occupational healthcare. In addition, it presents ongoing European and Swedish projects for developing personalized, and pervasive wearable systems for assessing risks of developing musculoskeletal disorders and cardiovascular diseases at work. Occupational healthcare should benefit in preventing diseases and disorders by providing the right feedback at the right time to the right person. Collected data from workers can provide evidence supporting the ergonomic and industrial tasks of redesigning the working environment to reduce the risks.

  • 15.
    Acevedo Gomez, Yasna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    On Gas Contaminants, and Bipolar Plates in Proton Exchange Membrane Fuel Cells2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The proton exchange membrane (PEM) fuel cell is an electrochemical device that converts chemical energy into electrical energy through two electrocatalytic reactions. The most common catalyst used is platinum on carbon (Pt/C), which has shown the best performance in the fuel cell until now. However, the drawback of this catalyst is that it does not tolerate impurities, and both hydrogen and oxygen may carry small amounts of impurities depending on the production sources. The purpose of this thesis is to understand the effect of two impurities that are less investigated, i.e., ammonia, which may accompany the hydrogen rich reformates from renewable sources, and nitrogen dioxide, which may come from air pollution. The mechanism of contamination and an adequate recovery method for the respective contaminant are studied. Additionally, electroplated bipolar plates with Ni-Mo and Ni-Mo-P coatings were tested as alternatives to stainless steel and carbon materials.

    The results show that ammonia not only provokes changes in the polymer membrane but also in the oxygen reduction reaction (ORR), hydrogen oxidation reaction (HOR) and catalyst ionomer in both electrodes. The extent of performance recovery after the contamination depends on the concentration used and the exposure time. In contrast, nitrogen dioxide affects the catalyst in the electrode directly; the contamination is related to side reactions that are produced on the catalyst’s surface. However, NO2 is not attached strongly to the catalyst and it is possible to restore the performance by using clean air. The time the recovery process takes depends on the potential applied and the air flow.

    Finally, the evaluation of electroplated Ni-Mo and Ni-Mo-P on stainless steel by ex situ and in situ studies shows that these coatings reduce the internal contact resistance (ICR) and the corrosion rate of the stainless steel considerably. However, the in situ experiments show that phosphorus addition to the coating does not improve the fuel cell performance; thus, the Ni-Mo alloy is found to be a promising choice for electroplating stainless steel bipolar plates.

  • 16.
    Acevedo Gomez, Yasna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lagergren, Carina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Effect of nitrogen dioxide impurities on PEM fuel cell performanceManuscript (preprint) (Other academic)
    Abstract [en]

    Air is the most practical and economical oxidant to feed to the cathode in a proton exchange membrane fuel cell (PEMFC). However, the air is accompanied by small amounts of impurities that affect the performance of the fuel cell. Among these, nitrogen dioxide is the impurity that has been least investigated, and its effect is not fully understood. In this study, a possible mechanism is proposed based on the contamination of the fuel cell at different concentrations and adsorption potentials, and by employing stripping cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The results at different concentrations showed that the catalyst sites are blocked by the adsorption of NO2, and that there is a non-linear relationship between the concentration and degradation. The degradation is suggested to be related to the formation of intermediate species, as also shown by the pseudo-inductive impedance at the concentration of 100 and 200 ppm. Furthermore, the cyclic voltammetry showed that there is an oxidation to NO3- at 1.05 V, followed by the reduction of this specie to NO2- at 0.68 V, and a subsequent reduction of NO2- to N2O and/or NH2OH.

  • 17.
    Acevedo Gomez, Yasna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lagergren, Carina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Performance recovery after contamination with nitrogen dioxide in a PEM fuel cellManuscript (preprint) (Other academic)
    Abstract [en]

    While the market of fuel cell vehicles is increasing, these vehicles will still coexist with combustion engine vehicles on the roads and will be exposed to an environment with significant amounts of contaminants that will decrease the durability of the fuel cell. In order to investigate different recovery methods, a PEM fuel cell is in this study contaminated with 100 ppm of NO2 at the cathode side. The possibility to recover the cell performance is studied by using different airflow rates, different current densities, and by subjecting the cell to successive polarization curves. The results show that the successive polarization curves are the best choice for recovery; it took 35 min to reach full recovery of cell performance, compared to 4.5 hours of recovery with pure air at 0.5 A cm-2 and 110 ml min-1. However, the performance recovery at a current density of 0.2 A cm-2 and air flow 275 ml min-1 was done in 66 min, which is also a possible alternative. Additionally, two operation techniques are suggested and compared during 7 h of operation; air recovery and air depletion. The air recovery technique shows to be a better choice than the air depletion technique.

  • 18. Addicoat, Matthew
    et al.
    Atkin, Rob
    Canongia Lopes, José Nuno
    Costa Gomes, Margarida
    Firestone, Millicent
    Gardas, Ramesh
    Halstead, Simon
    Hardacre, Christopher
    Hardwick, Laurence J.
    Holbrey, John
    Hunt, Patricia
    Ivaništšev, Vladislav
    Jacquemin, Johan
    Jones, Robert
    Kirchner, Barbara
    Lynden-Bell, Ruth
    MacFarlane, Doug
    Marlair, Guy
    Medhi, Himani
    Mezger, Markus
    Pádua, Agílio
    Pantenburg, Isabel
    Perkin, Susan
    Reid, Joshua E. S. J.
    Rutland, Mark W.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Saha, Satyen
    Shimizu, Karina
    Slattery, John M.
    Swadźba-Kwaśny, Malgorzata
    Tiwari, Shraeddha
    Tsuzuki, Seiji
    Uralcan, Betul
    van den Bruinhorst, Adriaan
    Watanabe, Masayoshi
    Wishart, James
    Structure and dynamics of ionic liquids: general discussion2018In: Faraday discussions (Online), ISSN 1359-6640, E-ISSN 1364-5498, Vol. 206, no 0, p. 291-337Article in journal (Refereed)
  • 19.
    Adolfsson, Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Carbon flake coated cellulose filters as dual function devices for rapid environmental contaminant detectionManuscript (preprint) (Other academic)
  • 20.
    Adolfsson, Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Hydrothermal recycling of natural and synthetic polymers to functional carbon materials2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Utilizing renewable recourses and waste recycling are necessary for reaching a circular resource society. The concept of this thesis was to set up a sustainable recycling route, suitable even for low quality biopolymer and plastic waste for production of functional carbon materials. Carbonaceous materials were prepared by mild hydrothermal carbonizations of cellulose and polypropylene (PP) under acidic conditions. The carbonization of cellulose resulted mainly in micro-/nanometer sized carbon spheres (CS) with polar functionalities. After carbonization of PP, products were found in solid and liquid phase. Completely carbonized solid carbons products were obtained from PP at 250 °C after 60 min. The liquid products from the same process displayed aromatics and exhibited fluorescence properties. In addition, new carbon materials were prepared by acid, base and thermal treatments of the carbonized products at low temperatures. Thermally resistant carbon products and antibacterial CS towards both Staphylococcus aureus and Pseudomonas aeruginosa were demonstrated as possible applications for these products. The minimum inhibitory concentrations of CS were 200-400 µg mL-1 depending on the bacteria strain and reached after only 3 h. Furthermore, nanometer sized carbon nanodots with high oxygenation degree and fluorescence properties were derived together with carbon flakes (CF) from the carbonized products. The CF with flat and micrometer sized morphology and polar groups were utilized for coating of cationized cellulose filters, applied as adsorbents and then subsequently as surfaces for SALDI-MS analysis of environmental contaminants. This work contributes with new routes to and applications for functional carbon materials.

    The full text will be freely available from 2020-04-30 10:30
  • 21.
    Adolfsson, Karin H.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Golda-Cepa, M
    Benyahia Erdal, Nejla
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Duch, J
    Kotarba, A
    Hakkarainen, Minna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Importance of Surface Functionalities for Antibacterial Properties of Carbon Spheres2019In: Advanced Sustainable Systems, ISSN 2366-7486Article in journal (Refereed)
    Abstract [en]

    Carbon spheres (CS) are interesting materials for antibacterial applications. Herein, CS are produced by a green process utilizing microwave-assisted hydrothermal treatment of cellulose. The CS are then postmodified in acidic and basic solutions to evaluate the influence of different functionalities on antibacterial properties. CS contain OH/COOH, C Symbol of the Klingon Empire C, and C Symbol of the Klingon Empire O functionalities, while O-CS produced by acid treatment of CS have additional COOH, and NH/NH2 groups, resulting in carbon spheres with negatively and positively charged groups in dispersion. Treatment with base (Na-CS) removes low molecular weight species with oxygen and results in carbon spheres with the highest C/O ratio. CS, O-CS, and Na-CS have nonporous morphology and are in micro/nanometer sizes, although, smaller sized spheres, hollow spheres, and fragments are also attained in the case of O-CS. O-CS show antibacterial activity toward both Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Pseudomonas aeruginosa (P. aeruginosa). The minimum inhibitory concentration is 200 and 400 mu g mL(-1) for S. aureus and P. aeruginosa, respectively, and is achieved only after 3 h of incubation. Neither CS nor Na-CS exhibit antibacterial activity. The antibacterial activity is suggested to originate from electrostatic interactions between O-CS and the bacteria.

  • 22.
    Adolfsson, Karin H.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lin, Chia-feng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Hakkarainen, Minna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Microwave Assisted Hydrothermal Carbonization and Solid State Postmodification of Carbonized Polypropylene2018In: ACS SUSTAINABLE CHEMISTRY & ENGINEERING, ISSN 2168-0485, Vol. 6, no 8, p. 11105-11114Article in journal (Refereed)
    Abstract [en]

    Functional carbon materials produced through a hydrothermal treatment of waste products have gained interest. Particularly, the method is considered more facile and green compared to conventional decomposition methods. Here, we demonstrated an upcycling of polypropylene (PP) waste to carbon materials by a microwave assisted hydro thermal treatment. The solid product obtained from the hydrothermal treatment was analyzed by multiple techniques to reveal the structure and the influence of processing conditions on PP degradation and hydrothermal carbonization. Chemical analyses showed the presence of carbonaceous material independent of acid amount (20 and 30 mL), temperature (210 and 250 degrees C), and time (20-80 min). A complete transformation of PP content to amorphous carbon required 60 min at 250 degrees C. The mass yield of the solid product decreased as a function of harsher processing conditions. At the same time, thermogravimetric analysis illustrated products with increasing thermal stability and a larger amount of remaining residue at 600 degrees C. The solid products consisted of irregular fragments and sheet-like structures. A solid state microwave process in air atmosphere was performed on a product with incomplete carbonization. The modification resulted in a decreased C/O ratio, and TGA analysis in nitrogen showed high thermal stability and degree of carbonization as indicated by the remaining residue of 86.4% at 600 degrees C. The new insights provided on the hydrothermal carbonization, and postmodification in air atmosphere, can catalyze effective handling of plastic waste by enabling transformation of low quality waste into functional carbon materials.

  • 23.
    Afrasiabi, Roodabeh
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Material Physics, MF.
    Söderberg, Lovisa
    KTH, School of Biotechnology (BIO), Proteomics and Nanobiotechnology.
    Jönsson, Håkan
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Nano Biotechnology.
    Björk, Per
    Andersson-Svahn, Helene
    KTH, School of Biotechnology (BIO), Nano Biotechnology (closed 20130101).
    Linnros, Jan
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics.
    Integration of a Droplet-Based Microfluidic System and Silicon Nanoribbon FET Sensor2016In: Micromachines, ISSN 2072-666X, E-ISSN 2072-666X, Vol. 7, no 134Article in journal (Refereed)
    Abstract [en]

    We present a novel microfluidic system that integrates droplet microfluidics with a silicon nanoribbon field-effect transistor (SiNR FET), and utilize this integrated system to sense differences in pH. The device allows for selective droplet transfer to a continuous water phase, actuated by dielectrophoresis, and subsequent detection of the pH level in the retrieved droplets by SiNR FETs on an electrical sensor chip. The integrated microfluidic system demonstrates a label-free detection method for droplet microfluidics, presenting an alternative to optical fluorescence detection. In this work, we were able to differentiate between droplet trains of one pH-unit difference. The pH-based detection method in our integrated system has the potential to be utilized in the detection of biochemical reactions that induce a pH-shift in the droplets.

  • 24.
    Agerskov, Niels
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Adaptable Semi-Automated 3D Segmentation Using Deep Learning with Spatial Slice Propagation2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Even with the recent advances of deep learning pushing the field of medical image analysis further than ever before, progress is still slow due to limited availability of annotated data. There are multiple reasons for this, but perhaps the most prominent one is the amount of time manual annotation of medical images takes. In this project a semi-automated algorithm is proposed, approaching the segmentation problem in a slice by slice manner utilising the prediction of a previous slice as a prior for the next. This both allows the algorithm to segment entirely new cases and gives the user the ability to correct faulty slices, propagating the correction throughout. Results on par with current state of the art is achieved within the domain of the training data. In addition to this, cases outside of the training domain can also be segmented with some accuracy, paving the way for further improvement. The strategy for training the network to utilise auxiliary input lies in the heavy online data augmentation, forcing the network to rely on the provided prior.

  • 25.
    Aghdam, Araz Sheibani
    et al.
    Sabanci Univ, Fac Engn & Nat Sci, TR-34956 Istanbul, Turkey..
    Ghorbani, Morteza
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems. Sabanci Univ, Fac Engn & Nat Sci, Mechatron Engn Program, TR-34956 Istanbul, Turkey;Sabanci Univ, Ctr Excellence Funct Surfaces & Interfaces NanoDi, TR-34956 Istanbul, Turkey..
    Deprem, Gokberk
    Sabanci Univ, Fac Engn & Nat Sci, Mechatron Engn Program, TR-34956 Istanbul, Turkey..
    Cebeci, Fevzi Cakmak
    Sabanci Univ, Fac Engn & Nat Sci, TR-34956 Istanbul, Turkey.;Sabanci Univ, SUNUM Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey..
    Kosar, Ali
    Sabanci Univ, Fac Engn & Nat Sci, Mechatron Engn Program, TR-34956 Istanbul, Turkey.;Sabanci Univ, Ctr Excellence Funct Surfaces & Interfaces NanoDi, TR-34956 Istanbul, Turkey.;Sabanci Univ, SUNUM Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey..
    A New Method for Intense Cavitation Bubble Generation on Layer-by-Layer Assembled SLIPS2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, article id 11600Article in journal (Refereed)
    Abstract [en]

    The importance of surface topology for the generation of cavitating flows in micro scale has been emphasized during the last decade. In this regard, the utilization of surface roughness elements is not only beneficial in promoting mass transportation mechanisms, but also in improving the surface characteristics by offering new interacting surface areas. Therefore, it is possible to increase the performance of microfluidic systems involving multiphase flows via modifying the surface. In this study, we aim to enhance generation and intensification of cavitating flows inside microfluidic devices by developing artificial roughness elements and trapping hydrophobic fluorinated lubricants. For this, we employed different microfluidic devices with various hydraulic diameters, while roughness structures with different lengths were formed on the side walls of microchannel configurations. The surface roughness of these devices was developed by assembling various sizes of silica nanoparticles using the layer-by-layer technique (D2). In addition, to compare the cavitating flow intensity with regular devices having plain surfaces (D1), highly fluorinated oil was trapped within the pores of the existing thin films in the configuration D2 via providing the Slippery Liquid-Infused Porous Surface (D3). The microfluidic devices housing the short microchannel and the extended channel were exposed to upstream pressures varying from 1 to 7.23 MPa. Cavitation inception and supercavitation condition occured at much lower upstream pressures for the configurations of D2 and D3. Interestingly, hydraulic flip, which rarely appears in the conventional conical nozzles at high pressures, was observed at moderate upstream pressures for the configuration D2 proving the air passage existence along one side of the channel wall.

  • 26.
    Aguilera Costa, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Uppgradering och identifiering av cellulosa och hemicellulosa i restströmmar från jordbruk och skogsindustri2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    By-products are in focus for further processing. Residues from agriculture and forest industry contain a large amount of fiber, and this work investigates the qualitative properties of residues and whether there is potential for using them in the cellulose industry.

    By-products collected were wheat straw, rapeseed straw, wheat bran, betfor, silage, branches, primary sludge, sawdust and fiber rejects. A literature study was conducted around each by-product to get a better understanding of what they consist of and how they occur.

    By extracting holocellulose from the by-products, the qualitative properties of the fibers were analyzed. For the slightest change in the shape and dimensions of fibers, a maceration method was used to extract holocellulose from the by-products.

    Methods used to analyze the qualitative properties of the by-products were viscosity, titrations and gravimetric analyzes. With these methods, mass exchanges, ash levels, mass viscosities, peracetic acid and hydrogen peroxide levels could be determined for the extracted holocellulose masses.

    To investigate whether the extracted holocellulose masses can be used in the cellulosic industry, two types of processes were tested. One was aerogel production and the other a compression mold to produce high strength biocomposites.

    It was found that the fiber rejects yielded the greatest holocellulose exchange compared to the other residues. The analyzes gave the result that sawdust had the fibers with the highest degree of polymerization while wheat bran and betfor had the fibers with the lowest degree of polymerization. The dissociation of the holocellulose mass could not be performed because the test sample had either a too high mass viscosity or a too high a proportion of hemicellulose which prevents the solvent from dissolving the fibers. Compression molding of the holocellulose mass from wheat straw was successful as it was possible to make the soft pulp a lot more rigid. Compression molding of the holocellulose masses may be an alternative for producing additive manufacturing materials (3D printing).

  • 27.
    Ahlinder, Astrid
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Fuoco, Tiziana
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Finne Wistrand, Anna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Medical grade polylactide, copolyesters and polydioxanone: Rheological properties and melt stability2018In: Polymer testing, ISSN 0142-9418, E-ISSN 1873-2348, Vol. 72, p. 214-222Article in journal (Refereed)
    Abstract [en]

    Rheological measurements have shown that lactide-based copolymers with L-lactide content between 50 and 100 mol% with varying comonomers, as well as polydioxanone (PDX), can be used in additive manufacturing analogously to poly(L-lactide) (PLLA) if their melt behaviour are balanced. The results indicate that copolymers can be melt processed if the temperature is adjusted according to the melting point, and parameters such as the speed are tuned to conteract the elastic response. Small amplitude oscillatory shear (SAOS) rheology, thermal and chemical characterisation allowed us to map the combined effect of temperature and frequency on the behaviour of six degradable polymers and their melt stability. Values of complex viscosity and Tan delta obtained through nine time sweeps by varying temperature and frequency showed that the molecular structure and the number of methylene units influenced the results, copolymers of L-lactide with D-Lactide (PDLLA) or glycolide (PLGA) had an increased elastic response, while copolymers with trimethylene carbonate (PLATMC) or epsilon-caprolactone (PCLA) had a more viscous behaviour than PLLA, with respect to their relative melting points. PDLLA and PLGA require an increased temperature or lower speed when processed, while PLATMC and PCLA can be used at a lower temperature and/or higher speed than PLLA. PDX showed an increased viscosity compared to PLLA but a similar melt behaviour. Negligible chain degradation were observed, apart from PLGA.

  • 28.
    Ahlquist, Mårten S. G.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Marcos-Escartin, Rocio
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Bicarbonate hydrogenation by iron: Effects of solvent and ligand on the mechanism2018In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Article in journal (Other academic)
  • 29.
    Ahlquist, Mårten
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Zhan, Shaoqi
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Modeling molecular water oxidation catalysts at interfaces2018In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Article in journal (Other academic)
  • 30.
    Ahluwalia, A.
    et al.
    Italy.
    De Maria, C.
    Italy.
    Lantada, A. D.
    Spain.
    Pietro, L. D.
    Italy.
    Ravizza, A.
    Italy.
    Mridha, Mannan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Madete, J.
    Kenya.
    Makobore, P. N.
    Uganda.
    Aabloo, A.
    Estonia.
    Kitsing, R.
    Estonia.
    Leivobits, A.
    Estonia.
    Towards open source medical devices current situation, inspiring advances and challenges2018In: BIODEVICES 2018 - 11th International Conference on Biomedical Electronics and Devices, Proceedings; Part of 11th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2018, SciTePress, 2018, p. 141-149Conference paper (Refereed)
    Abstract [en]

    Open Source Medical Devices may be part of the solution towards the democratization of medical technologies pursuing Universal Health Coverage as part of the Sustainable Development Goals for United Nations. Recent technological advances, especially in information and communication technologies, combined with innovative collaborative design methodologies and manufacturing techniques allow for the mass-personalization of biodevices and help to optimize the related development times and costs, while keeping safety in the foreground through the whole life cycle of medical products. These advantages can be further promoted by adequately fostering collaboration, communication, high value information exchange, and sustainable partnerships and by extending the employment of open source strategies. To this end, within the UBORA project, we are developing a framework for training the biomedical engineers of the future in open-source collaborative design strategies and for supporting the sharing of information and the assessment of safety and efficacy in novel biodevices. An essential part of this open-source collaborative framework is the UBORA e-infrastructure, which is presented in this study, together with some initial success cases. Main future challenges, connected with regulatory harmonization, with educational issues and with accessible and open design and manufacturing resources, among others, are also presented and discussed.

  • 31.
    Ahluwalia, Arti
    et al.
    Univ Pisa, Dept Ingn Informaz, Bioengn, Pisa, Italy..
    De Maria, Carmelo
    Univ Pisa, Dept Ingn Informaz, Bioengn, Pisa, Italy..
    Diaz Lantada, Andres
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Madete, June
    Univ Pisa, Res Ctr E Piaggio, Pisa, Italy.;Kenyatta Univ, Nairobi, Kenya..
    Makobore, Philippa Ngaju
    Uganda Ind Res Inst, Instrumentat Div, Kampala, Uganda..
    Ravizza, Alice
    Univ Pisa, Pisa, Italy..
    Di Pietro, Licia
    Mridha, Mannan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Munoz-Guijosa, Juan Manuel
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Tanarro, Enrique Chacon
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Torop, Janno
    Tartu Ulikool, Inst Technol, Tartu, Estonia..
    Biomedical Engineering Project Based Learning: Euro-African Design School Focused on Medical Devices2018In: International Journal of Engineering ,Science and Innovative Technology, ISSN 0949-149X, E-ISSN 2277-3754, Vol. 34, no 5, p. 1709-1722Article in journal (Refereed)
    Abstract [en]

    Biomedical engineering (BME) has the potential of transforming medical care towards universal healthcare by means of the democratization of medical technology. To this end, innovative holistic approaches and multidisciplinary teams, built upon the gathering of international talent, should be encouraged within the medical industry. However, these transformations can only be accomplished if BME education also continuously evolves and focuses on the internationalization of students, the promotion of collaborative design strategies and the orientation towards context relevant medical needs. In this study we describe an international teaching-learning experience, the "UBORA (Swahili for 'excellence') Design School". During an intensive week of training and collaboration 39 engineering students lived through the complete development process for creating innovative open-source medical devices following the CDIO ("conceivedesign-implement-operate") approach and using the UBORA e-infrastructure as a co-design platform. Our post-school survey and analyses showed that this integral teaching-learning experience helped to promote professional skills and could nurture the future generation of biomedical engineers, who could transform healthcare technology through collaborative design oriented to open source medical devices.

  • 32.
    Ahmad, Shargeel
    et al.
    Dalian Univ Technol, Inst Artificial Photosynthesis, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Liu, Jinxuan
    Dalian Univ Technol, Inst Artificial Photosynthesis, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Ji, Wei
    Dalian Univ Technol, Inst Artificial Photosynthesis, State Key Lab Fine Chem, Dalian 116024, 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. Dalian Univ Technol, Inst Artificial Photosynthesis, State Key Lab Fine Chem, Dalian 116024, Peoples R China.;KTH Royal Inst Technol, Sch Chem Sci & Engn, Dept Chem, S-10044 Stockholm, Sweden..
    Metal-Organic Framework Thin Film-Based Dye Sensitized Solar Cells with Enhanced Photocurrent2018In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 11, no 10, article id 1868Article in journal (Refereed)
    Abstract [en]

    Metal-organic framework thin film-based dye sensitized solar cell is fabricated with highly oriented, crystalline, and porous Zn-perylene metal-organic framework (MOF) thin film (SURMOF) which is integrated with Bodipy embedded in poly(methyl methacrylate). It has been demonstrated that the photocurrent can be enhanced by a factor of 5 relative to Zn-perylene MOF thin film due to triplet-triplet annihilation up-conversion between the Bodipy/PMMA sensitizer and the Zn-perylene MOF thin film acceptor using Co(bpy)(3)(2+/3+) as redox mediator.

  • 33. Ahmed, Mona
    et al.
    Baumgartner, Roland
    Aldi, Silvia
    Dusart, Philip
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Cellular and Clinical Proteomics.
    Hedin, Ulf
    Gustafsson, Bjorn
    Caidahl, Kenneth
    Human serum albumin-based probes for molecular targeting of macrophage scavenger receptors2019In: International Journal of Nanomedicine, ISSN 1176-9114, E-ISSN 1178-2013, Vol. 14, p. 3723-3741Article in journal (Refereed)
    Abstract [en]

    Background: Inflammation and accumulation of macrophages are key features of unstable atherosclerotic plaques. The ability of macrophages to take up molecular probes can be exploited in new clinical imaging methods for the detection of unstable atherosclerotic lesions. We investigated whether modifications of human serum albumin (HSA) could be used to target macrophages efficiently in vitro. Materials and methods: Maleylated and aconitylated HSA were compared with unmodified HSA. Fluorescent or radiolabeled (Zr-89) modified HSA was used in in vitro experiments to study cellular uptake by differentiated THP-1 cells and primary human macrophages. The time course of uptake was evaluated by flow cytometry, confocal microscopy, real-time microscopy and radioactivity measurements. The involvement of scavenger receptors (SR-Al, SR-B2, LOX-1) was assessed by knockdown experiments using RNA interference, by blocking experiments and by assays of competition by modified low-density lipoprotein. Results: Modified HSA was readily taken up by different macrophages. Uptake was mediated nonexclusively via the scavenger receptor SR-Al (encoded by the MSR1 gene). Knockdown of CD36 and ORL1 had no influence on the uptake. Modified HSA was preferentially taken up by human macrophages compared with other vascular cell types such as endothelial cells and smooth muscle cells. Conclusions: Modified Zr-89-labeled HSA probes were recognized by different subsets of polarized macrophages, and maleylated HSA may be a promising radiotracer for radio-nuclide imaging of macrophage-rich inflammatory vascular diseases.

  • 34.
    Ahmed, Mona
    et al.
    Karolinska Inst, Dept Mol Med & Surg, Ctr Mol Med, S-17176 Stockholm, Sweden..
    Gustafsson, Björn
    Karolinska Inst, Dept Mol Med & Surg, Ctr Mol Med, S-17176 Stockholm, Sweden..
    Aldi, Silvia
    Karolinska Inst, Sect Med Inflammat Res, Dept Med Biochem & Biophys, S-17177 Stockholm, Sweden..
    Dusart, Philip
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Cellular and Clinical Proteomics. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Egri, Gabriella
    Surflay Nanotec GmbH, Max Planck Str 3, D-12489 Berlin, Germany..
    Butler, Lynn M.
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Cellular and Clinical Proteomics.
    Bone, Dianna
    Karolinska Inst, Dept Mol Med & Surg, Ctr Mol Med, S-17176 Stockholm, Sweden..
    Dahne, Lars
    Surflay Nanotec GmbH, Max Planck Str 3, D-12489 Berlin, Germany..
    Hedin, Ulf
    Karolinska Inst, Dept Mol Med & Surg, Ctr Mol Med, S-17176 Stockholm, Sweden..
    Caidahl, Kenneth
    Karolinska Inst, Dept Mol Med & Surg, Ctr Mol Med, S-17176 Stockholm, Sweden.;Univ Gothenburg, Sahlgrenska Acad, Inst Med, Dept Mol & Clin Med, S-41345 Gothenburg, Sweden..
    Molecular Imaging of a New Multimodal Microbubble for Adhesion Molecule Targeting2019In: Cellular and Molecular Bioengineering, ISSN 1865-5025, E-ISSN 1865-5033, Vol. 12, no 1, p. 15-32Article in journal (Refereed)
    Abstract [en]

    Introduction: Inflammation is an important risk-associated component of many diseases and can be diagnosed by molecular imaging of specific molecules. The aim of this study was to evaluate the possibility of targeting adhesion molecules on inflammation-activated endothelial cells and macrophages using an innovative multimodal polyvinyl alcohol-based microbubble (MB) contrast agent developed for diagnostic use in ultrasound, magnetic resonance, and nuclear imaging. Methods: We assessed the binding efficiency of antibody-conjugated multimodal contrast to inflamed murine or human endothelial cells (ECs), and to peritoneal macrophages isolated from rats with peritonitis, utilizing the fluorescence characteristics of the MBs. Single-photon emission tomography (SPECT) was used to illustrate 99m Tc-labeled MB targeting and distribution in an experimental in vivo model of inflammation. Results: Flow cytometry and confocal microscopy showed that binding of antibody-targeted MBs to the adhesion molecules ICAM-1, VCAM-1, or E-selectin, expressed on cytokine-stimulated ECs, was up to sixfold higher for human and 12-fold higher for mouse ECs, compared with that of non-targeted MBs. Under flow conditions, both VCAM-1- and E-selectin-targeted MBs adhered more firmly to stimulated human ECs than to untreated cells, while VCAM-1-targeted MBs adhered best to stimulated murine ECs. SPECT imaging showed an approximate doubling of signal intensity from the abdomen of rats with peritonitis, compared with healthy controls, after injection of anti-ICAM-1-MBs. Conclusions: This novel multilayer contrast agent can specifically target adhesion molecules expressed as a result of inflammatory stimuli in vitro, and has potential for use in disease-specific multimodal diagnostics in vivo using antibodies against targets of interest.

  • 35.
    Ahuja, Dipali
    et al.
    Univ Limerick, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Dept Chem Sci, Castletroy, Co Limerick, Ireland..
    Svärd, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena. Univ Limerick, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Dept Chem Sci, Castletroy, Co Limerick, Ireland..
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena. Univ Limerick, Synth & Solid State Pharmaceut Ctr, Bernal Inst, Dept Chem Sci, Castletroy, Co Limerick, Ireland..
    Investigation of solid-liquid phase diagrams of the sulfamethazine-salicylic acid co-crystal2019In: CrystEngComm, ISSN 1466-8033, E-ISSN 1466-8033, Vol. 21, no 18, p. 2863-2874Article in journal (Refereed)
    Abstract [en]

    The influence of temperature and solvent on the solid-liquid phase diagram of the 1 : 1 sulfamethazinesalicylic acid co-crystal has been investigated. Ternary phase diagrams of this co-crystal system have been constructed in three solvents: methanol, acetonitrile and a 7 : 3 (v/v) dimethylsulfoxide-methanol mixture, at three temperatures. The system exhibits congruent dissolution in acetonitrile and the co-crystal solubility has been determined by a gravimetric technique. The Gibbs energy of co-crystal formation from the respective solid components has been estimated from solubility data, together with the corresponding enthalpic and entropic component terms. The Gibbs energy of formation ranges from -5.7 to -7.7 kJ mol -1, with the stability increasing with temperature. In methanol and the DMSO-methanol mixture, the co-crystal dissolves incongruently. It is shown that the solubility ratio of the pure components cannot be used to predict with confidence whether the co-crystal will dissolve congruently or incongruently. The size of the region where the co-crystal is the only stable solid phase is inversely related to the pure component solubility ratio of salicylic acid and sulfamethazine.

  • 36.
    Akhter, Shirin
    et al.
    Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala Bioctr, Dept Plant Biol, Uppsala, Sweden..
    Kretzschmar, Warren W.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Nordal, Veronika
    Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala Bioctr, Dept Plant Biol, Uppsala, Sweden..
    Delhomme, Nicolas
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Umea, Sweden..
    Street, Nathaniel R.
    Umea Sweden, Dept Plant Physiol, Umea Plant Sci Ctr, Umea, Sweden..
    Nilsson, Ove
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Umea, Sweden..
    Emanuelsson, Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Sundström, Jens F.
    Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala Bioctr, Dept Plant Biol, Uppsala, Sweden..
    Integrative Analysis of Three RNA Sequencing Methods Identifies Mutually Exclusive Exons of MADS-Box Isoforms During Early Bud Development in Picea abies2018In: Frontiers in Plant Science, ISSN 1664-462X, E-ISSN 1664-462X, Vol. 9, article id 1625Article in journal (Refereed)
    Abstract [en]

    Recent efforts to sequence the genomes and transcriptomes of several gymnosperm species have revealed an increased complexity in certain gene families in gymnosperms as compared to angiosperms. One example of this is the gymnosperm sister Glade to angiosperm TM3-like MADS-box genes, which at least in the conifer lineage has expanded in number of genes. We have previously identified a member of this subclade, the conifer gene DEFICIENS AGAMOUS LIKE 19 (DAL19), as being specifically upregulated in cone-setting shoots. Here, we show through Sanger sequencing of mRNA-derived cDNA and mapping to assembled conifer genomic sequences that DAL19 produces six mature mRNA splice variants in Picea abies. These splice variants use alternate first and last exons, while their four central exons constitute a core region present in all six transcripts. Thus, they are likely to be transcript isoforms. Quantitative Real-Time PCR revealed that two mutually exclusive first DAL19 exons are differentially expressed across meristems that will form either male or female cones, or vegetative shoots. Furthermore, mRNA in situ hybridization revealed that two mutually exclusive last DAL19 exons were expressed in a cell-specific pattern within bud meristems. Based on these findings in DAL19, we developed a sensitive approach to transcript isoform assembly from short-read sequencing of mRNA. We applied this method to 42 putative MADS-box core regions in P abies, from which we assembled 1084 putative transcripts. We manually curated these transcripts to arrive at 933 assembled transcript isoforms of 38 putative MADS-box genes. 152 of these isoforms, which we assign to 28 putative MADS-box genes, were differentially expressed across eight female, male, and vegetative buds. We further provide evidence of the expression of 16 out of the 38 putative MADS-box genes by mapping PacBio Iso-Seq circular consensus reads derived from pooled sample sequencing to assembled transcripts. In summary, our analyses reveal the use of mutually exclusive exons of MADS-box gene isoforms during early bud development in P. abies, and we find that the large number of identified MADS-box transcripts in P. abies results not only from expansion of the gene family through gene duplication events but also from the generation of numerous splice variants.

  • 37.
    Alander, B.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Capezza, A.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials. Department of Plant Breeding, The Swedish University of Agricultural Sciences, Box 101, Alnarp, Sweden.
    Wu, Q.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Johansson, E.
    Olsson, Richard T.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Hedenqvist, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    A facile way of making inexpensive rigid and soft protein biofoams with rapid liquid absorption2018In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 119, p. 41-48Article in journal (Refereed)
    Abstract [en]

    A novel and facile method to produce inexpensive protein biofoams suitable for sponge applications is presented. The protein used in the study was wheat gluten (WG), readily available as a by/co-product, but the method is expected to work for other cross-linkable proteins. The foams were obtained by high-speed stirring of pristine WG powder in water at room temperature followed by drying. Glutaraldehyde was used to crosslink the foam material in order to stabilize the dispersion, reduce its tackiness and improve the strength of the final foam. The foams were of medium to high density and absorbed readily both hydrophobic and hydrophilic liquids. The foam structure, consisting primarily of an open pore/channel system, led to a remarkably fast capillary-driven (pore-filling only) uptake of a hydrophobic liquid (limonene). Essentially all uptake occurred within the first second (to ca. 90% of the dry weight). In a polar liquid (water), the rapid pore-filling occurred in parallel with a more time-dependent swelling of the foam matrix material. Further improvement in the foam strength was achieved by making a denser foam or adding TEMPO-oxidized cellulose nanofibres. Soft foams were obtained by adding glycerol.

  • 38.
    Albertsson, Ann-Christine
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Celebrating 20 years of Biomacromolecules!2019In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, no 2, p. 767-768Article in journal (Refereed)
  • 39.
    Albertsson, Ann-Christine
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    CELL 104-Renewable and/or degradable polymers2007In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 233, p. 796-796Article in journal (Other academic)
  • 40.
    Albertsson, Ann-Christine
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Micro- and macromolecular design of aliphatic polyesters2015In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 249Article in journal (Other academic)
  • 41.
    Aldabbagh, Zina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    En undersökning av Rönningesjöns miljötillstånd, särskilt när det gäller metaller2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Lake Rönningesjön lies in a geological fault (a crack) and it is affected by the clay in the surrounding fields. The pH-values lie within the interval 7.1–7.7. The lake is also impacted by the roads around the lake. The incoming water contains large amounts of road salt. From the cars also large amounts of metal ions are transported by the incoming storm water. In this project copper, chromium and lead are measured. Most of the metals in the lake pass through the wetland at Löttingelund in one end of the lake and flows through the lake to the outlet, which delivers the metal ions into Hägernäsviken, which is a part of the Baltic Sea. However, a part of the metal ions are precipitated in the lake. The concentrations of metal ions in the lake water are too high. Metal ions are also stored in the sediments. Special dams should be constructed to remove particle bound metals from the storm water, by sedimentation.

  • 42.
    Aldahan, Leith
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Kudoori, Ivan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Utvärdering av roterande borstlösfrekvensomformare tillspårledningar2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Track lines are used in subway stations to show the train locations and determine the speed of the train by chopping the frequency. The frequency of the track lines is obtained from a rotary frequency converter. In today's stations, rotary frequency converters with brushes are commonly used. These emit a great deal of heat in some relays and produce environmental problems in the form of carbon dust from the brushes. The existing systems have been used for over 30 years and obtaining spare parts and conducting maintenance on the systems can be difficult.

    This degree project examines the possibility of newer systems being built on a rotating brushless frequency converter, where the spare parts and servicing would be available for at least the next 25 years.

    The project surveys and compares different rotating brushless frequency converters from different suppliers to find an identical frequency converter to meet the requirements of the Traffic Administration.

    The result of this study has had a lot of focus on the problem area with the brushed frequency converter that produces harmful substances such as carbon dust and the heat in the relay room. Discussions with manufacturing companies of rotating brushless frequency converters have been made during this study where possible options were discussed for further development of the system in relay rooms. The result has also discussed the possibilities of using the new system of frequency converters with brushless motor and generator instead of the current brushed frequency converter available in the facility. The result has also shown that the rotating brushless frequency converter can convert the frequency to 75 Hz. The new system meets RAMS requirements of the Trafikförvaltning, and the system lasts for at least 25 years. This was a major requirement of the Trafikförvaltning, which was fulfilled during this study.

  • 43.
    Alekseeva, L. A.
    et al.
    Natl Acad Sci Ukraine, B Verkin Inst Low Temp Phys & Engn, 47 Nauky Ave, UA-61103 Kharkov, Ukraine..
    Dobryden, Illia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Determination of the low-temperature self-diffusion coefficient in solid p-H-2 from creep experiments2018In: Low temperature physics (Woodbury, N.Y., Print), ISSN 1063-777X, E-ISSN 1090-6517, Vol. 44, no 9, p. 946-951Article in journal (Refereed)
    Abstract [en]

    Dependencies of the relative elongation epsilon under the constantly applied stress at T = 1.8 K on the endurance time t of polycrystalline parahydrogen (p-H-2, similar to 0.2% of o-H-2) of high purity (99.9999 mol.%), with varying deuterium content, were measured. The region of linear dependence between the measured creep rates (epsilon) over dot of samples and the applied stress s was revealed. The conclusion that the low-temperature creep of the studied p-H-2 possesses a vacancy-type diffusion character was made on the basis of linear dependence (epsilon) over dot similar to s. Determination of the low-temperature self-diffusion coefficient of vacancies D in solid p-H-2, which characterizes the rate of low-temperature mass transfer, was performed. The cases of migration of vacancies in the crystal bulk, along boundaries separating individual crystallites, as well as between dislocations existing in crystals, are considered. A significant decrease in the (epsilon) over dot and D values with an increase in the isotope concentration in the samples was observed, while maintaining the linear relationship between (epsilon) over dot and s for the studied p-H-2. Published by AIP Publishing.

  • 44.
    Alemrajabi, M.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Forsberg, Kerstin
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Korkmaz, Kivanc
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Transport Phenomena.
    Rasmuson, Åke Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Isolation of rare earth element phosphate precipitate in the nitrophosphate process for manufacturing of fertilizer2016Conference paper (Refereed)
  • 45.
    Alemrajabi, Mahmood
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Recovery of Rare Earth Elements from an Apatite Concentrate2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Rare earth elements (REE) are a group of 17 elements including lanthanides, yttrium and scandium; which are found in a variety of classes of minerals worldwide. The criticality of the application, lack of high grade and economically feasible REE resources and a monopolistic supply situation has raised significant attention in recovery of these metals from low grade ores and waste materials. In this thesis, the recovery of REE from an apatite concentrate, containing 0.5 mass% of REE, within the nitrophosphate route of fertilizer production has been investigated. Most of the REE (≥ 95%) content can be recovered into a phosphate precipitate with almost 30 mass% REE. Different processes have been developed to convert the REE phosphate precipitate into a more soluble form to obtain a solution suitable for further REE purification and individual separation. It has been shown that after reprecipitation of the REE phosphate concentrate as REE sodium double sulphate and then transformation into a REE hydroxide concentrate, a solution containing 45g/L REE free of Ca, Fe and P can be obtained. The results suggest that the apatite waste after processing of iron ore have the potential to be a very important source for REE in Europe and that the economy is strongly supported by the simultaneous extraction of phosphorous.

    The potential of using hollow fiber supported liquid membrane (HFSLM) extraction in individual and group separation of REE has been investigated. A hollow fiber supported liquid membrane plant in pilot scale has been operated according to the three main configurations: standard hollow fiber supported liquid membrane technology (HFSLM); hollow fiber renewal liquid membrane technology (HFRSLM) and emulsion pertraction technology (EPT). The standard HFSLM operation is more selective than HFRSLM and EPT, while higher metal transport rate is observed in EPT followed by HFRSLM and HFSLM. The HFRLM configuration helps to maintain the performance of the liquid membrane.

  • 46.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Korkmaz, Kivanc
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Dephosphorization and impurity removal from a rare earth phosphate concentrate2017Conference paper (Refereed)
  • 47.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Recovery of phosphorous and rare earth elements from an apatite concentrate2018Conference paper (Refereed)
  • 48.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Korkmaz, Kivanc
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Processing of a rare earth phosphate concentrate obtained in the nitrophosphate process of fertilizer production2019In: Hydrometallurgy, ISSN 0304-386X, E-ISSN 1879-1158Article in journal (Refereed)
  • 49.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Transport Phenomena.
    Rasmuson, Åke C.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Transport Phenomena.
    Korkmaz, Kivanc
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Transport Phenomena.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Recovery of rare earth elements from nitrophosphoric acid solutions2017In: Hydrometallurgy, ISSN 0304-386X, E-ISSN 1879-1158, Vol. 169, p. 253-262Article in journal (Refereed)
    Abstract [en]

    In the present study, the recovery of rare earth elements (REEs) from an apatite concentrate in the nitrophosphate process of fertilizer production has been studied. The apatite concentrate has been recovered from iron ore tailings in Sweden by flotation. In the first step, the apatite is digested in concentrated nitric acid, after which Ca(NO3)2.4H2O is separated by cooling crystallization. The solution is then neutralized using ammonia whereby the REEs precipitate mainly as phosphates (REEPO4.nH2O) and together with calcium as REEn Cam (PO4)(3n + 2m) / 3. In this work, the degree of rare earth coprecipitation during seeded cooling crystallization of Ca(NO3)2.4H2O has been studied. The solubility of calcium nitrate tetrahydrate (Ca(NO3)2.4H2O) in acidic nitrophosphoric acid solutions in the temperature range of − 2 °C to 20 °C has been determined. For the neutralization step, it is shown that the calcium concentration and the final pH play an important role in determining the concentration of REEs in the precipitate. It is found that reaching maximum recovery of REE with minimum simultaneous precipitation of calcium requires careful control of the final pH to about 1.8. It is further observed that the precipitation yield of REEs and iron is favored by a longer residence time and higher temperature. Finally, the effect of seeding with synthesized REE phosphate crystals as well as a mixture of REE and Ca phosphates on the precipitation rate and the composition of the precipitate was studied.

  • 50.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Korkmaz, Kivanc
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Resource recovery.
    Upgrading of a rare earth phosphate concentrate within the nitrophosphate process2018In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 198, p. 551-563Article in journal (Refereed)
    Abstract [en]

    In the nitrophosphate process of fertilizer production, rare earth elements (REE) can be recovered as a REE phosphate concentrate. In this process, after digestion of apatite in concentrated nitric acid, Ca(NO3)2.4H2O is first separated by cooling crystallization and then the REE are precipitated in phosphate form by a partial neutralization step using ammonia. The obtained REE phosphate concentrate is contaminated by mainly calcium and iron, and the main solid phases are CaHPO4.2H2O, FePO4.2H2O and REEPO4.nH2O.

    In this study, a process to obtain a concentrate more enriched with REE with low concentration of calcium and iron and free of phosphorous is developed. In the developed process, enrichment and dephosphorization of the rare earth phosphate concentrate has been achieved by selective dissolution and re-precipitation of the REE as a sodium REE double sulfate salt. It is shown that by selective dissolution of the REE concentrate in nitric acid at a pH of 2.4, most of the calcium and phosphorus are dissolved, and a solid phase more enriched in REE is obtained. Thereafter, the REE phosphate concentrate is first dissolved in a mixture of sulfuric-phosphoric acid and then the REE are reprecipitated as NaREE(SO4)2.H2O by addition of a sodium salt. More than 95% of the Ca, Fe and P are removed and a REE concentrate containing almost 30 mass% total REE is obtained.

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