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  • 1.
    Choi, Byungchul
    et al.
    Chonnam Natl Univ, South Korea.
    Park, Su Han
    Chonnam Natl Univ, South Korea.
    Chiarmonti, David
    RE CORD Renewable Energy COnsortium R&D, Garbagnate Monastero, LC, Ital.
    Bae, Hyeun-Jong
    Chonnam Natl Univ, South Korea.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Inst Technol KTH, Stockholm, Sweden.
    Sustainable alcohol fuels promoting mobility and climate stabilization: The 21st International Symposium on Alcohol Fuels2015Inngår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 160, s. 561-565Artikkel i tidsskrift (Fagfellevurdert)
  • 2.
    Danish, M
    et al.
    East China University of Science and Technology, Shanghai, China.
    Gu, Xiaogang
    East China University of Science and Technology, Shanghai, China.
    Lu, Shuguang
    East China University of Science and Technology, Shanghai, China.
    Xu, Minhui
    East China University of Science and Technology, Shanghai, China.
    Xiang, Zhang
    East China University of Science and Technology, Shanghai, China.
    Fu, Xiaori
    East China University of Science and Technology, Shanghai, China.
    Xue, Yunfei
    East China University of Science and Technology, Shanghai, China.
    Miao, Zhouwei
    East China University of Science and Technology, Shanghai, China.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Nasir, Muhammad
    IRCBM, COMSATS Institute of Information Technology, Lahore, Pakistan.
    Role of reactive oxygen species and effect of solution matrix in trichloroethylene degradation from aqueous solution by zeolite-supported nano iron as percarbonate activator2016Inngår i: Research on chemical intermediates (Print), ISSN 0922-6168, E-ISSN 1568-5675, Vol. 42, nr 9, s. 6959-6973Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The role of reactive oxygen species (ROSs) and effect of solution matrix have been investigated for the degradation of trichloroethylene (TCE). Zeolite-supported nano iron (Z-nZVI) was synthesized as an activator to catalyze sodium percarbonate (SPC) with or without hydroxylamine, i.e. as reducing agent (RA). The probe tests confirmed the generation of OH·and O2−· in the Z-nZVI activated SPC system in absence of the RA, while the presence of RA significantly increased the generation of OH· and O2−· radicals. Scavenger tests demonstrated that OH· was the main ROS responsible for TCE degradation, whereas O2−· also participated in TCE degradation. From the solution matrix perspective, the experimental results confirmed significant scavenging effects of Cl− (1.0, 10.0, and 100 mmol L−1) and HCO3− (1.0 and 10.0 mmol L−1), whereas the scavenging effects were fairly impeded at 100 mmol L−1concentration of HCO3−. On the other hand, a considerable decline in scavenging effect was observed in the presence of RA in tested Cl− and HCO3− concentration ranges. In addition, negligible scavenging effects of NO3− and SO42− anions were found in all tested concentrations. The effect of initial solution pH on catalytic activity indicated a significant increase in the TCE degradation in the presence of RA even at higher pH value of 9. The results indicated that the Z-nZVI activated SPC system in presence of RA can effectively degrade chlorinated organic solvents, but it is important to consider the intensive existence of anions in groundwater.

  • 3.
    Danish, Muhammad
    et al.
    East China University of Science and Technology, Shanghai, China.
    Gu, Xiaogang
    East China University of Science and Technology, Shanghai, China.
    Lu, Shuguang
    East China University of Science and Technology, Shanghai, China.
    Farooq, Usman
    East China University of Science and Technology, Shanghai, China.
    Ahmad, Ayyaz
    University of Engineering and Technology, Multan, Pakistan.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Xue, Yunfei
    East China University of Science and Technology, Shanghai, China.
    Zhang, Xiang
    East China University of Science and Technology, Shanghai, China.
    Effect of solution matrix and pH in Z-nZVI-catalyzed percarbonate system on the generation of reactive oxygen species and degradation of 1, 1, 1-trichloroethane2017Inngår i: Water Science and Technology: Water Supply, ISSN 1606-9749, E-ISSN 1607-0798, Vol. 17, nr 6, s. 1568-1578Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study primarily focuses on evaluating the effects of solution matrix and pH for the generation of reactive oxygen species (ROSs) in Z-nZVI-catalyzed sodium percarbonate (SPC) system to degrade 1,1,1-trichloroethane (1,1,1-TCA) in the absence and presence of reducing agent (RA) i.e. hydroxylamine. 1,1,1-TCA degradation was 49.5% and 95% in the absence and presence of RA. Probe tests confirmed the generation of major hydroxyl radicals (OH•) and minor superoxide species (O2–•), and scavenger tests verified the key role of OH• and less of O2–• radicals. 1,1,1-TCA degradation decreased significantly in the presence of Cl− and HCO3–, while NO3– and SO42– have negligible effects in absence of RA. Addition of RA significantly enhanced 1,1,1-TCA degradation by generating more OH• and O2–• radicals in presence of anions. 1,1,1-TCA degradation increased in acidic range (1–5) while, an inhibitive trend from neutral to basic (7–9) was observed. On the contrary, a significant increase in 1,1,1-TCA degradation was observed with addition of RA in all pH values (1–9). In conclusion, the anions and pH significantly influenced the generation and intensity of ROSs and 1,1,1-TCA was effectively degraded in Z-nZVI-catalyzed SPC system in the presence of RA.

  • 4.
    Dilanson, Nadea
    Mälardalens högskola, Institutionen för biologi och kemiteknik. Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Halfsphere Derivatisation of Magnetic Micro Particles2008Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Abstract

     

    This exam project is an effort to derivatize one side of magnetic beads with one kind of molecule  , and another one on the opposite side. First the surface of the sphere is loaded with a suitable linker with, e.g. amino or hydroxyl groups. In the second step, these groups are derivatized with a photosensitive protecting group such as Nitroveratryloxycarbonyl. In the third step, the particles are placed on a surface and then irradiated with UltraViolet light (320 nm) from above, which will cleave off the Nitroveratryloxycarbonyl on the upper half, while leaving in place the ones at the lower half. The linker groups of the upper half can now be derivatized by other reagents of choice. The remaining Nitroveratryloxycarbonyl groups can be removed by suspending the particles in a solvent and then exposing them to UltraViolet light. Finally the linker groups on this half of the particles can be derivatized by a second reagent.

    Magnetic particles were marked with FITC, two different kinds of magnetic particles were selected, sikastar-NH2 function and sikastar-COOH function. Five different solvents were used to wash the magnetic particles and remove the bounded FITC, solvents are Acetone, 1-butanol, DMSO, 4-propanol, and Urea. Magnetic particles sikastar-NH2 and sikastar-COOH were washed with Tween 20 and SDS to remove non-specific binding of FITC. Sikastar particles were treated with IgG*FITC in constant presence of the following solvents: PBS*10, Pluronic-F127, Tween 20. Pegylation of sikastar particles got done to reduce non-specific binding. Derivatisation of Nitroveratryloxycarbonyl got done and specific bindning of IgG*FITC to micromer particles got done by protein thiolation.

    When a different concentration of FITC was tested to control specific and non-specific binding to sikastar functions, we observed that we had a specific binding to sikastar-NH2 in the lowest concentration. In choice of magnetic particles we had specific binding with sikastar-NH2. Using a different solvents Acetone, 1-butanol, 4-propanol, and Urea  to remove bounded FITC, sikastar-NH2 showed stronger fluoresence than sikastar-COOH after washing because of specific binding and it was difficult to remove FITC with Acetone, 1-butanol,  4-propanol,and Urea, on the other hand DMSO could remove bounded FITC from sikastar particles. When we washed magnetic particles sikastar-NH2 and sikastar-COOH with Tween 20 and SDS to remove non-specific binding of FITC, we could see that magnetic particles showed fluoresence in both functions due to non-specific binding. When sikastar particles got treated with IgG*FITC in constant presence of solvents PBS*10, Pluronic-F127, and Tween 20, we had a specific binding between sikastar particles and IgG*FITC in a presence of pluronic-F127. Pegylation of sikastar particles with a different kind of a PEG was possibl to reduce non-specific bindning. The derivatisation of Nitroveratryloxycarbonyl could be done in a N2 environment, and Nitroveratryloxycarbonyl-sikastar-NH2 could be radiated with UltraViolet light to remove Nitroveratryloxycarbonyl. Also thiolation method could be used to perform specific binding of IgG*FITC to micromer particles.

    Fulltekst (pdf)
    FULLTEXT01
  • 5.
    Edström, Evelina
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Hillström, Martin
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Produktutveckling miljöteknik: Framtagning av produkt som varnar vid förskämning av mjölk2017Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    The aim of the thesis, industrial product design PPU304, is to develop a new product that will reduce food waste of dairy products in households. The main objective is that the product will be able to measure and signal when the milk has expired.The thesis is a start to find the solution to some of the food waste in households which is a major environmental issue in today's society. The goal is to develop a flexible expiration date that can reduce food wastage. With today's sensor technology bacterial levels can be calculated from the milk and that can increase the time a pack of milk can be used. The greater knowledge and awareness humanity have for environmental issues the better world we will live in. To understand the question, “what is it that makes the milk unfit for consumption?” A part of the work has gone into researching the technological aspect. In consumer ready milk there is different bacteria that will grow over time and eventually spoil the milk, how this process works varies depending on what or which bacteria manage to grow the most. Therefore, the most appropriate technique is to measure bacteria in the milk and identify at which level the milk passes its actual expiration date.The design of the product has been guided by two major factors, the predetermined dimensions of the circuit board and the adaptation to the size of the milk carton. The shape of the product is an oblong rear part with a spherical body at the front. The edges are rounded to give a pleasantand smooth feeling to the hand using the product.The thesis in industrial product design resulted in a final concept. The product analyses the amount of bacteria in the milk through sensors that measure bacterial metabolism. The data gets interpreted and displayed through the use of LEDs. To save energy the concept is equipped with a photo resistor that deactivates the LEDs when the fridge is closed and dark. The conclusion of the thesis, performed at Millcroft AB is at a conceptual level. To go from idea to product, is a process that takes a long time to complete and often involves many different moments. The timeframe during this study is considered too short to cover all parts of the product and therefore the boundaries set and the focus has been on constructing a design that fits the estimated technology as well as consumer needs. Some suggestions are that more research in the technical aspect of the product should be concluded. Further testing of dairy sustainability should be conducted on a larger scale and further development of the technology to send data.

    Fulltekst (pdf)
    fulltext
  • 6.
    Ghalali, Aram
    Mälardalens högskola, Institutionen för biologi och kemiteknik. Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    STATINS AND INCREASED EFFICACY OF CANCER TREATMENT2008Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Abstract

    Activation of the PI3K/Akt signaling cascade is often associated with advanced forms of prostate cancer cells, DU145. This is likely explained by the common loss of the PTEN gene in majority of cancer cells. This study have documented that low concentration of atorvastatin, a drug inhibiting HMG-CoA reductase and cholesterol metabolism, decreased the level of insulin-induced phosphorylated Akt in the nucleus.

    The statins effect on Akt/protein kinase B signaling and the sensitizing effect of cytostatic drugs have been investigated in this study and it were found that cytostatic drugs induced Akt phosphorylation and nuclear translocation was inhibited by atorvastatin in A549 and DU145 cells. Inhibition of PI3K with LY294002 was observed by MTT assay, and it were noticed that atorvastatin increased the effect of LY294002.

    The main point of the study was the localization of the tumor suppressor PTEN. This gene acts as a plasma-membrane lipid-phosphatase antagonizing the phosphoinositide 3-kinase/Akt cell survival pathway. The nuclear localization of PTEN is a central for its activity. The insulin-induced A549 cells were treated with atorvastatin, thereafter very rapid change in PTEN localization was observed.

    The study is preformed in view of good laboratory practice, GLP. In this study GLP applies to non-clinical experiment conducted for the assessment of the safety of chemicals (the concentration of the atorvastatin) to man and the environment.

     

  • 7.
    Granstam, Cecilia
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Improvement of biocompatibility of neuroprosthesis devices for long term use; an initial assessment2008Independent thesis Basic level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Abstract

    The aim of this project was to contribute to the improvement of Neuroprobe arrays regarding the biocompatibility by providing those with three different modified biopolymers, either hyaluronic acid, dextran or poly(ethylene glycol). In addition, the biopolymers were tested with two different molecular weights. To get a deeper understanding of the behaviour and configuration of the biopolymers on surfaces, gold, native silicon oxide and artificially made silicon oxide wafers were immobilised with the modified biopolymers and analysed with Atomic Force Microscope and X-ray Photoelectron Spectroscopy. Furthermore, derivatisations of the biopolymers were carried out and in some extent they were amended if possible. The task was to find out which one of the three biopolymers being most suited in the context.

    The first step was to provide the biopolymers with a SS-pyridyl group. The SS-Pyridyl group is reactive towards the gold wafer surface and towards the thiols introduced on the native silicon oxide and the artificial made silicon oxide wafer surfaces via a mercaptopropyl derivatisation. The second step was to immobilise the biopolymers on the gold, native silicon oxide and artificial silicon oxide wafer surfaces and then to analyse them with Atomic Force Microscope and X-ray Photoelectron Spectroscopy. The former step was performed at Mälardalens University and the latter step was performed at Ångströms Laboratory, Uppsala University.

    Atomic Force Microscope pictures and X-ray Photoelectron Spectroscopy measurements were analyzed and evaluated in order to find the biopolymer most suited in the context. In addition, poly(ethylene glycol) was cut from the project leaving the two remaining biopolymers, hyaluronic acid and dextran, open for persual. The outcome gave the hyaluronic acid a slight advantage over dextran considering the results of this project and also the fact that hyaluronic acid occurs as a natural substance within the brain of mammals. Moreover, the surface which the biopolymers were immobilised on did matter. The conformation of the biopolymer seemed to change depending on the surfaces composition. In contrast, the molecular weight of the biopolymers seemed to have less influence.

  • 8.
    Hamidi, Helaleh
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Optimering av FISH- teknik för detektion av Laktobaciller2008Independent thesis Advanced level (degree of Magister), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Sammanfattning

    Syftet med den här studien var att utveckla och optimera FISH (Fluorescense In Situ Hybridisation) tekniken som en snabb och ganska billig metod för detektion av laktobaciller. Det vill säga att kunna på objektsglas använda FISH tekniken för att identifiera laktobaciller på artnivå med fluorescensmärkta prober mot 16S och 23S RNA. FISH är en allmän och användbar metod för att detektera och lokalisera mikroorganismer eller en specifik grupp av mikroorganismer i provet (1). Metoden detekterar DNA- eller RNA- sekvenser med hjälp av fluorescensmärkta prober som hybridiseras specifikt med komplementära målsekvenser i intakta celler (2). Detta innebär att man behåller cellmorfologin och tillför en lättdetekterad fluorescerande färg. I början av studien utvaldes två grupper av bakterier, gramnegativa bakterier som har tunnare cellvägg, vilket underlättar hybridiseringen och grampositiva laktobacillus med en tjockare cellvägg. Enligt tidigare undersökningar gav FISH tekniken bra resultat om rätt probe användes för rätt organism. Som anvisning till den här studien användes en tidigare studie på E.coli K12.(6). I början av den här studien användes samma prober som i studien med E.coli K12. Bakterierna i grupp 1 valdes utifrån homologi mellan probernas sekvens och målsekvensen hos bakterierna. De hade 100 % homologi med probe 1 och hög homologi, 83-100 %, med probe 2 ,vilket väl överensstämmer med resultatet för E. coli. Bakterierna odlades i lämpliga medier och prov togs från log-fas. Bakterierna behandlades med hybridiseringsbuffert och studerades under fluorescensmikroskop. Stark fluorescens iakttogs i flertalet av bakterierna i de fall som homologi mellan probe och målsekvens var hög. Effekten av tiden för förvaring i kyl efter skörd på fluorescensförmågan studerades också. Fluorescensen efter en dag jämfördes med fluorescensen efter 15 dagar och 30 dagar hos samma bakterie. Bakterierna fotograferades i fluorescensmikroskop samt ljusmikroskop och resultaten presenteras i respektive tabeller och/eller bilder. Resultaten visade en sänkning i fluorescensstyrka och i antal bakterier som lyste redan efter 15 dagar. Efter 30 dagar hade nästan alla bakterier upphört att reagera med proben, oavsett vilken art som studerades. Slutligen studerades kvaliteten på tvättningar. Fluorescensbilder togs av bakterierna efter en tvätt och jämfördes med bilder efter 2 och tre tvättar. Ingen stor skillnad observerades efter flera tvättningar jämförd med en tvätt. Studien visade att den teknik som utvecklades är användbar för att detektera specifika sekvenser både i grampositiva och gramnegativa bakterier.

    Fulltekst (pdf)
    FULLTEXT01
  • 9.
    Hofling, Ann
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Upprätta processbeskrivning och utvärdera processtabilitet för en fermenteringsprocess2008Independent thesis Basic level (degree of Bachelor), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Inledning

    Vid Unitech Biopharma, Matfors (Sverige) sker tillverkning av rekombinant Kolera Toxin

    subenhet B (rCTB-213), vilket är en av de aktiva substanserna i vaccinet Dukoral®.

    Unitech Biopharma AB är ett bioteknikföretag fokuserade på legotillverkning av

    rekombinanta proteiner och tillverkar rCTB för SBL Vaccin AB Solna, (Sverige).

    Anläggningen där tillverkningen av denna produkt sker har alla nödvändiga tillstånd

    (Läkemedelsverket, Länsstyrelsen, Arbetsmiljöverket) och uppfyller gällande cGMP-krav

    samt är godkänd av läkemedelsmyndigheterna i EU och Kanada, WHO samt i ytterligare ca

    35 andra länder.

    Dukoral® är ett drickbart vaccin som stimulerar immunförsvaret i tarmen och skapar ett bra

    skydd mot sjukdomen kolera. Vaccinet ger även skydd mot enterotoxinbildande stammar av

    Escherichia coli (ETEC) vars värmekänsliga toxin (LT) delvis liknar koleratoxinet både

    strukturellt, funktionellt och immunologiskt[34]. Vaccinet består förutom rCTB av tre olika

    stammar inaktiverade Vibrio Cholerae bakterier, vilka produceras vid SBL-vaccin AB, där

    även slutformulering av vaccinet sker.

    Tillverkningsprocessen av Monovalent bulk rCTB-213 sker genom mikrobiell fermentering

    av en genetiskt modifierad produktionsstam av Vibrio Cholerae, där huvudodlingssteget sker i

    500 liters skala där hela tillvekningsprocessen sker under Good Manifacturing Practise (GMP)

    förhållanden för att garantera en säker, effektiv och kvalitetsmässigt bra produkt.

    Målet med detta examensarbete är att upprätta en processbeskrivning för

    tillverkningsprocessen av Monovalent bulk rCTB-213. Beskrivningen skall baseras på den

    process som görs idag och innefatta respektive processtegs mål, teori och kritiska parametrar.

    Den kunskap som skapas genom att definiera och kartlägga (dvs. dokumentera arbetsflödet) i

    en process har ett stort värde i sig, den är dessutom en utomordentlig plattform för

    förbättringsarbete genom att den skapar en gemensam bild av vad som sker i processen i dag.

    I detta examensarbete sker även en sammanställning av produktionen av Monovalent bulk

    rCTB-213 för perioden februari 2004 - juni 2005.

    Fakta om hur processen tidigare har betett sig måste användas som bas för

    förbättringsarbete[1].

    För att se om eventuell förekomst av variation för enskilda variabler kan urskiljas, utvärderas

    processdata för variabler som dokumenterats av företaget för batcher tillverkade under

    perioden februrari 2004 tom. juni 2005.

    Under fermentationssteget regleras parametrarna temperatur, pH och andelen löst syre i

    huvudfermentorn för att upprätthålla optimal fysisk miljö för tillväxt och rCTB produktion.

    För att få en uppfattning om hur dessa parameterar förhållit sig vid odlingar som utförts under

    perioden februari 2004 – juni 2005 utvärderas dessa variabler via

    duglighetsanalys/processkapabilitetsstudie (Cpk). I denna studie beräknas de korrigerade

    duglighetsindexen för de ovan nämda parametrarna, där den naturliga spridningen för

    processen sätts i förhållande till vilka gränser som är angivna i registreringsdokument

    (Process Manifacturing Description) för att få en uppfattning om det som är angivet i

    registrerings- dokument efterlevs.

    Fulltekst (pdf)
    FULLTEXT01
  • 10.
    Holmlund, Anna
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Mälardalens högskola, Institutionen för biologi och kemiteknik.
    Molecular interactions of proinsulin C-peptide2008Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The proinsulin C-peptide has long been thought as a byproduct from the insulin synthesis were it promotes the folding of the A and B-chain of insulin, but several studies in the past decade has shown that C-peptide is a bioactive peptide that can be beneficial in preventing diabetes complications. Patients with type I diabetes mellitus that has received C-peptide doses has shown for example improved renal function, increased blood flow in skeletal muscle and stimulated glucose transport. The aim of this study was to investigate the inter- and intramolecular binding properties of the proinsulin C-peptide, and in particular to study if the peptide forms oligomers and how the oligomerization is affected by additatives such as metal ions, insulin and sodium chloride. A method to identify C-peptide by SDS- and Native PAGE was developed. Using this technique, proinsulin C-peptide was found to form oligomers in μM concentrations. The oligomerization was dependent on the concentration, time and temperature. Metal ions such as Mg+, Zn2+ and Fe2+ affected the oligomerization. Insulin was shown to affect the oligomeric states of the C-peptide and to promote its disaggregation. Oligomerization of C-peptide was also detected with Surface Plasmon Resonance. Further studies are needed to find out how these finding can relate to the bioactivity of C-peptide.

    Download (pdf)
    SUMMARY01
  • 11.
    Karlsson, Anders
    Mälardalens högskola, Institutionen för biologi och kemiteknik. Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Adhesion av mikroorganismer till lignocellulosa2008Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The aim of the project was to develop a method to investigate differences in adhesion of microorganisms to materials that contains lignocellulose. The method was tested on a gram-positive (Micrococcus lutea) and one gram-negative (E-coliJM109) bacteria.

    The study was begun by cultivation of the two microorganisms. The cultivation was done to calculate the generation times of the bacteria and to obtain growth curves. Cells from these cultivations were also frozen (-70ºC) and later used for inoculation.

    At STFI-Packforsk AB the total charge on the mass was measured and later a conductivity titration on the mass was executed as well, all to find out more about the different properties of the mass. Properties that in a later part of this study could possibly be linked to the adhesion of cells to the pulp. The adhesion experiments that were executed gave poor results. The adhesion experiment with M. lutea was the only experiment that gave a reproducible result. In this experiment M. lutea was contacted with bleached leaf. A reduction of cells was observed in all of the dilutions where M. lutea had been in contact with the mass. The number of colony forming units of the culture was 1,2×107 before the adhesion and 2×106 subsequently.

     

    Fulltekst (pdf)
    FULLTEXT02
  • 12.
    Karlsson, Christer
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    New Methods for Adaptation to Degeneration in Process Models for Process Industries2009Inngår i: Chemical Product and Process Modeling, Vol. Vol. 4, nr : Iss. 1, s. , Article 25.-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The implementation of model-based control and diagnostics suffer strongly from the fact that models deteriorate as a function of process and sensor deterioration. Also, changes in the raw material (i.e. wood) may occur and often the process control is not addressing these variations in reality. It is thus vital for the model system to be robust in the sense that it is transparent and easy for the operator to maintain. Robustness is essential in many parts of the system, including measurement, process model validation, the ability of the model to adapt to changes in the process, optimization algorithms, and of course the model itself. In this paper, we first show three real-life applications of the utilization of models for diagnostics and control. Thereafter conditions for on-line adaptation of the models are discussed. The challenges when designing such a system are in achieving operator confidence, filtering of misleading measured data, adaptation of process parameters when the process parameters change, and combining validation of measurements and process models. These challenges are met by using a combination of physical and statistical models and methods based on them such as model predictive control (MPC) and parameter estimation. The model should be maintained by a qualified engineer who should be able to explain the system to the operator so that it is understood and confidence can be maintained.

  • 13.
    Kyprianidis, Konstantinos
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Skvaril, JanMälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Developments in Near-Infrared Spectroscopy2017Collection/Antologi (Fagfellevurdert)
    Abstract [en]

    Over the past few decades, exciting developments have taken place in the field of near-infrared spectroscopy (NIRS). This has been enabled by the advent of robust Fourier transform interferometers and diode array solutions, coupled with complex chemometric methods that can easily be executed using modern microprocessors. The present edited volume intends to cover recent developments in NIRS and provide a broad perspective of some of the challenges that characterize the field. The volume comprises six chapters overall and covers several sectors. The target audience for this book includes engineers, practitioners, and researchers involved in NIRS system design and utilization in different applications. We believe that they will greatly benefit from the timely and accurate information provided in this work.

  • 14.
    Ledung, Greger
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Heterogenization of a Cobalt Porphyrin Catalyst Investigated by Scanning Probe Microscopy and X-Ray Photoelectron Spectroscopy: The Effect on Catalysis of Oxidation Reactions2008Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Construction of advanced materials through self-assembly on the molecular level is an important route to achieve novel functionality. Self-assembly of thiols onto gold has during the last decades shown greate promise in the creation of functional nanomaterials, such as sensors or catalysts, but for many applications silicon should be a better substrate since it offers semiconducting properties and better processing abilities in addition to being cheaper. This work describes an efficient novel method to incorporate reactive disulfide bonds onto a silica surface under mild reaction conditions. The reactive thiol groups introduced onto the silica surface will be oxidized but is then converted into highly reactive thiopyridyl groups, which can easily be utilized for further organic synthesis involving thiol-containing molecules.

    Cobalt tetraarylporphyrins with thioacetate-functionalized carbon chains on the aryl groups were synthesized (CoTPP-L) and were used as a model system for investigating catalytic activity in homogeneous and heterogeneous oxidation catalysis. For heterogeneous catalysis CoTPP-L was immobilized onto gold surfaces through thiol-gold self-assembly, and onto silica surfaces by the above mentioned disulfide exchange method.

    The properties of the molecular layers were characterized on the molecular level by means of X-ray photoelectron spectroscopy (XPS) and scanning probe microscopy (SPM). The immobilization on gold surfaces took place through the formation of multiple thiolate bonds and it could be controlled by varying the preparation scheme. More thiolate bonds form if the thioacetyl protective groups of the thiol linkers are cleaved off prior to immobilization. The CoTPP-L molecules were in all cases found to form stable disordered monolayers on gold surfaces. On silica surfaces the CoTPP-L forms patchwise multilayers.

    The catalytic performance of the heterogenized systems (CoTPP-L immobilized onto gold or silicon wafers) was evaluated and it was found that the strong inactivation observed for their homogeneous congener was avoided. As a result, the turnover number per molecule in heterogeneous catalysis was at least 100 times higher than that of the corresponding homogeneous catalyst. It is thus demonstrated that the performance of these catalysts can be dramatically improved if the catalyst arrangement can be controlled on the molecular level. Work is ongoing to extend the system to high surface area materials.

    Fulltekst (pdf)
    FULLTEXT01
  • 15.
    Li, Hailong
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Jakobsen, Jana P
    SINTEF Energy.
    Wilhelmsen, Øivind
    SINTEF Energy.
    Yan, Jinyue
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    PVTxy properties of CO2 mixtures relevant for CO2 capture, transport and storage: Review of available experimental data and theoretical models2011Inngår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 88, nr 11, s. 3567-3579Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The knowledge about pressure–volume–temperature–composition (PVTxy) properties plays an importantrole in the design and operation of many processes involved in CO2 capture and storage (CCS) systems.A literature survey was conducted on both the available experimental data and the theoreticalmodels associated with the thermodynamic properties of CO2 mixtures within the operation windowof CCS. Some gaps were identified between available experimental data and requirements of the systemdesign and operation. The major concerns are: for the vapour–liquid equilibrium, there are no data aboutCO2/COS and few data about the CO2/N2O4 mixture. For the volume property, there are no publishedexperimental data for CO2/O2, CO2/CO, CO2/N2O4, CO2/COS and CO2/NH3 and the liquid volume of CO2/H2. The experimental data available for multi-component CO2 mixtures are also scarce. Many equationsof state are available for thermodynamic calculations of CO2 mixtures. The cubic equations of state havethe simplest structure and are capable of giving reasonable results for the PVTxy properties. More complexequations of state such as Lee–Kesler, SAFT and GERG typically give better results for the volumeproperty, but not necessarily for the vapour–liquid equilibrium. None of the equations of state evaluatedin the literature show any clear advantage in CCS applications for the calculation of all PVTxy properties.A reference equation of state for CCS should, thus, be a future goal.

    Fulltekst (pdf)
    fulltext
  • 16.
    Li, Hailong
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Wilhelmsen, Øivind
    SINTEF Energy Research.
    Lv, Yuexia
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Wang, Weilong
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Yan, Jinyue
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Viscosities, thermal conductivities and diffusion coefficients of CO2 mixtures:Review of experimental data and theoretical models2011Inngår i: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 5, nr 5, s. 1119-1139Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Accurate experimental data on the thermo-physical properties of CO2-mixtures are pre-requisites fordevelopment of more accurate models and hence, more precise design of CO2 capture and storage (CCS)processes. A literature survey was conducted on both the available experimental data and the theoreticalmodels associated with the transport properties of CO2-mixtures within the operation windows ofCCS. Gaps were identified between the available knowledge and requirements of the system design andoperation. For the experimental gas-phase measurements, there are no available data about any transportproperties of CO2/H2S, CO2/COS and CO2/NH3; and except for CO2/H2O(/NaCl) and CO2/amine/H2Omixtures, there are no available measurements regarding the transport properties of any liquid-phasemixtures. In the prediction of gas-phase viscosities using Chapman–Enskog theory, deviations are typically<2% at atmospheric pressure and moderate temperatures. The deviations increase with increasingtemperatures and pressures. Using both the Rigorous Kinetic Theory (RKT) and empirical models in theprediction of gas-phase thermal conductivities, typical deviations are 2.2–9%. Comparison of popularempirical models for estimation of gas-phase diffusion coefficients with newer experimental data forCO2/H2O shows deviations of up to 20%. For many mixtures relevant for CCS, the diffusion coefficientmodels based on the RKT show predictions within the experimental uncertainty. Typical reported deviationsof the CO2/H2O system using empirical models are below 3% for the viscosity and the thermalconductivity and between 5 and 20% for the diffusion coefficients. The research community knows littleabout the effect of other impurities in liquid CO2 than water, and this is an important area to focus infuture work.

    Fulltekst (pdf)
    fulltext
  • 17.
    Lindholm, Tobias
    Mälardalens högskola, Institutionen för biologi och kemiteknik.
    Energioptimering för Recip Strängnäs AB2008Independent thesis Advanced level (degree of Magister), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Recip Strängnäs AB är ett miljöcertifierat företag som framställer och förpackar penicillin produkter. Företaget måste göra vissa reparationer på ett av ventilationssystemen. De tar tillfället i akt att gå igenom energiomsättningen i helhet då åtgärder redan måste göras. På grund av det ökade oljepriset och mer fokus på miljön är det intressant att byta ut denna energikälla som används idag, vilket är ånga som produceras genom eldning av olja. Den energikälla som är tänkt att ersätta ångan är fjärrvärme.

    Flera processer som företaget använder sig av kräver ånga, men beräkningar visar att det bara behövs ca 400 MWh/år för att driva dessa processer. Då den totala energiomsättningen för Recip Strängnäs AB är kring 3100 MWh/år skulle det preliminärt innebära en besparing på 120 000 kr/år för att gå över till att använda fjärrvärme där det är möjligt istället för ånga.

    Det hygienvatten som används på Recip Strängnäs AB kostar i dagsläget ca 76 000 kr/år att värma. En övergång till fjärrvärme skulle sänka den kostnaden till ca 66 000 kr/år. Tanken är dock att använda sig av båda kondensatvattnet, som samlas upp i kondensattanken, och den spillvärme som produceras av värmeväxlaren för ånga, destillationen och kompressorerna till att förvärma hygienvattnet. I denna rapport presenteras två alternativ på hur det kan lösas.

    Även drifttiderna för de större fläktarna har setts över. Genom att ställa ner dem till mer anpassade tider kan elkostnaderna minskas med kring 87 000kr/år.

    Det finns ytterligare möjligheter att sänka kostnaderna. Det är bland annat genom att ställa om kylkompressorn så att den använder mindre vatten och istället höjer temperaturen på det vatten som släpps ut. Det är möjligt att ställa dem på så vis att det går att använda det varma vattnet för uppvärmning av vissa processer. Den fungerar då som en värmepump.

    Vid drageringen finns det ett utgående flöde av varmluft på drygt 40ºC som inte används till något. Genom att installera en värmepump mellan utgående och ingående lufttrumma är det möjligt att minska energiförbrukningen för drageringen med ca 50 %. Det visade sig dock att installationskostnaderna blev högre än priset på den sparade energin.

    Fulltekst (pdf)
    FULLTEXT01
  • 18.
    Mirmoshtaghi, Guilnaz
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Assessment on the impact of including hydrodynamics on the performance of kinetic based models for bubbling fluidized bed gasifiersManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    One of the approaches to model fluidized bed gasifiers is to combine the reaction kinetics and bed hydrodynamics. The kinetic part of the model deals with the chemical reactions occurring in different steps of gasification while hydrodynamics of the bed gives more information about the physical phenomena inside the bed. In this paper two major fluidization models; two phase theory (TPT) and counter current back mixing (CCBM) and one kinetic rate model have been developed and compared in terms of accuracy in predicting product gas concentration and the generality of the model to different ranges of input parameters. The results show that including hydrodynamics of the bed as in TPT improves the accuracy of the kinetic rate model. TPT model can be used for air gasification in bubbling fluidized bed gasifiers while for steam gasification it needs further modification.

  • 19.
    Mirmoshtaghi, Guilnaz
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Biomass gasification in fluidized bed gasifiers: Modeling and simulation2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Using woody biomass as a resource for production of biofuel, heat and power through gasification has been studied for years. In order to reduce the cost of operating and to design the full-scale gasification plant developing a general model to be applicable for different ranges of input data with acceptable level of accuracy, is needed. In order to develop such model for the gasifier, as the main component in the process, three major models have been studied in this thesis; theoretical model (Equilibrium model), semi-empirical model (modified equilibrium model, kinetic combined with hydrodynamic model) and empirical model (statistical model).

    Equilibrium model (EM), shows low accuracy in predicting the content ofmajor components in product gas especially CH4 and CO. Therefore to improve the accuracy of prediction modification of EM is needed. Analyzing the semi-empirical approaches show that although the accuracy of EM can be improved, the generality of the modified models are still low. Therefore two new modified models have been developed. The first model is based on including data from wider range of operating condition to develop the empirical equation. The second model is based on combining QET and reaction kinetics for char gasification approaches. The first model decreases the overall error from 44% to 31% while the overall error of second model is decreased from 36% to 8%. Other semi-empirical model for fluidized bed gasifiers which is not equilibrium-based is developed by combining reaction kinetics with hydrodynamic equations. Investigating different hydrodynamic models show that combining two-phase-structure model with reaction kinetics for bubbling fluidized bed gasifiers improves the accuracy of the kinetic-only model.

    The third type of approaches, investigated in this thesis, towards developing a general model is the empirical model. This model has been developed based on Partial least square (PLS) approach. The PLS-R model show high level of accuracy within the specific range of empirical data used for developing the model. Further analysis on the experimental dataset by PLS-R model show that equivalence ratio (ER) is the operating parameter with the most significant impact on the performance of fluidized bed gasifiers. Optimizing the operation of fluidized bed gasifiers based on this model shows that high gas quality (high volume fraction of H2, CO and CH4 and low volume fraction of CO2), high carbon conversion and low tar yield is achieved when ER≈0.3, Steam to Biomass ratio≈0.7, moisture content≈9% and particle size≈3mm and olivine is the bed material. 

    Fulltekst (pdf)
    fulltext
  • 20.
    Mirmoshtaghi, Guilnaz
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Mälardalen Högskola.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    EVALUATION OF DIFFERENT BIOMASS GASIFICATION MODELING APPROACHES FOR FLUIDIZED BED GASIFIERS2016Inngår i: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 91, s. 69-82Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To develop a model for biomass gasification in fluidized bed gasifiers with high accuracy and generality that could be used under various operating conditions, the equilibrium model (EM) is chosen as a general and case-independent modeling method. However, EM lacks sufficient accuracy in predicting the content (volume fraction) of four major components (H2, CO, CO2 and CH4) in product gas. In this paper, three approaches—MODEL I, which restricts equilibrium to a specific temperature (QET method); MODEL II, which uses empirical correlations for carbon, CH4, C2H2, C2H4, C2H6 and NH3 conversion; and MODEL III, which includes kinetic and hydrodynamic equations—have been studied and compared to map the barriers and complexities involved in developing an accurate and generic model for the gasification of biomass.

    This study indicates that existing empirical correlations can be further improved by considering more experimental data. The updated model features better accuracy in the prediction of product gas composition in a larger range of operating conditions. Additionally, combining the QET method with a kinetic and hydrodynamic approach results in a model that features less overall error than the original model based on a kinetic and hydrodynamic approach.

  • 21.
    Mirmoshtaghi, Guilnaz
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Skvaril, Jan
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    The influence of different parameters on biomass gasification in circulating fluidized bed gasifiers2016Inngår i: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 126, s. 110-123Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The mechanism of biomass gasification has been studied for decades. However, for circulating fluidized bed (CFB) gasifiers, the impacts of different parameters on the gas quality and gasifiers performance have still not been fully investigated. In this paper, different CFB gasifiers have been analyzed by multivariate analysis statistical tools to identify the hidden interrelation between operating parameters and product gas quality, the most influencing input parameters and the optimum points for operation. The results show that equivalence ratio (ER), bed material, temperature, particle size and carbon content of the biomass are the input parameters influencing the output of the gasifier the most. Investigating among the input parameters with opposite impact on product gas quality, cases with optimal gas quality can result in high tar yield and low carbon conversion while low tar yield and high carbon conversion can result in product gas with low quality. However using Olivine as the bed material and setting ER value around 0.3, steam to biomass ratio to 0.7 and using biomass with 3 mm particle size and 9 wt% moisture content can result in optimal product gas with low tar yield.

  • 22.
    Mirmoshtaghi, Guilnaz
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Westermark, Mats
    Royal Institute of Technology, Stockholm, Sweden.
    Mohseni, Farzad
    Royal Institute of Technology, Stockholm, Sweden.
    Simulation of a lab-scale methanation reactor2012Inngår i: Simulation of a lab-scale methanation reactor, 2012Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Due to the worldwide effort on developing renewable fuels, methane production by different methods has gained considerable interest. Considering the difficulties in producing methane from renewable sources such as biomass or black liquor, an interesting methanation reaction for increasing methane concentration in produced gas, found to be hydrogenation of carbon dioxide and is called Sabatier reaction.The present research is on simulation and optimization of the Sabatier reaction in a catalytic bed of Ruthenium on Alumina base. The simulation is based on two different scenarios: first, an adiabatic reactor with interstage cooling and second; an isothermal tube reactor with wall coolingIn this highly exothermic reaction, most of the produced heat must be removed by external cooling in order to prevent too high increase of the bed temperature. Regarding the design optimization done in the project, the best results occur for the isothermal case in 600K and 10 bar, while for the adiabatic run an interstage cooling strategy with 5 coolers and 6 reactors has been modeled. Additionally, recycling some part of cooled product to the entrance can increase the efficiency and reduce the number of reactors for the adiabatic strategy.The conclusion to this study shows that isothermal operation with external cooling is more favorable for lab-scale studies while adiabatic interstage design with recirculation of product gas would be more feasible in full scale cases.

    Key words: methanation reactor, Ruthenium catalyst, isothermal, adiabatic

  • 23.
    Naqvi, Muhammad
    KTH, Energiprocesser.
    Bio-refinery system integrated with pulp and paper mills using black liquor gasification2010Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Mitigation of climate change and energy security are major driving forces for increased biomass energy utilization. The pulp and paper industry consumes a large proportion of biomass worldwide that include bark, wood residues, and black liquor. Due to the fact that modern pulp and paper industries have established infrastructure for handling and processing biomass, it is possible to lay foundation for future gasification based bio-refineries to co-produce electricity, chemicals or bio-fuels together with pulp and paper products. There is a potential to export electricity or bio-fuels by improving today’s existing chemical pulp and paper mills integrating gasification technology.

    The present study evaluates the energy conversion performance of integrated black liquor gasification (BLG) within the chemical pulp mills in comparison with conventional pulp mill energy system. The objective is to investigate and compare various BLG technologies and bio-fuel production routes. The comparison is performed to identify the advantageous route based on system performance indicators e.g. bio-fuel production potential, fuel to product efficiency (FTPE), biomass import, overall system thermal energy efficiency, on-site CO2 reduction using carbon capture, and potential CO2 offsets from bio-fuel use in transport sector.

    The study on a variety of BLG configurations shows promising results for potential bio-fuel production offering significant contributions toward fossil fuel savings, emission reductions, and improved energy security. Methanol, synthetic natural gas (SNG) and dimethyl ether (DME) show promising features as potential fuel candidates. The comparative results show significantly larger bio-fuel production potential of black liquor conversion to SNG from catalytic hydrothermal gasification than DME, methanol or SNG production from the dry BLG (DBLG) and Chemrec BLG (CBLG) systems. The energy ratio of SNG production from the CHG system is higher than DME and methanol in the CBLG and the DBLG systems. When considering consequences of incremental biomass import, the DBLG system is far better than the CBLG and the CHG systems mainly due to the elimination of the lime kiln. Considerable reduction of on-site CO2 emissions could be achieved using CO2 capture and storage in the pulp mills. The CHG and the CBLG systems shows better performance results than the DBLG system comparing potential CO2 emissions offset from bio-fuels replacing fossil fuels.

  • 24.
    Nevalainen, Nina
    Mälardalens högskola, Institutionen för biologi och kemiteknik.
    Effects of glial cell line-derived neurotrophic factor (GDNF) on mouse fetal ventral mesencephalic tissue2008Independent thesis Advanced level (degree of Magister), 20 poäng / 30 hpOppgave
    Abstract [en]

    The symptoms of Parkinson's disease occur due to degeneration of dopamine neurons in substantia nigra. It has been demonstrated that glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic factor when it comes to protect and enhance survival of dopamine neurons in animal models of Parkinson's disease. The aim of this study was to evaluate short- and long-term effects of GDNF on survival and nerve fiber outgrowth of dopamine cells and astrocytic migration in mouse fetal ventral mesencephalic (VM) tissue. Primary tissue cultures were made of mouse fetal VM tissue and evaluated at 7 and 21 days in vitro (DIV) in terms of dopaminergic nerve fiber outgrowth and astrocytic migration when developed with GDNF present, partially, or completely absent. The results revealed that VM tissue cultured in the absence of GDNF did not exhibit any significant differences in migration of astrocytes or dopaminergic nerve fiber outgrowth neither after 7 DIV nor after 21 DIV, when compared with tissue cultured with GDNF present. Migration of astrocytes and dopaminergic nerve fiber outgrowth reached longer distances when tissue was left to develop for 21 DIV in comparison with 7 DIV. In order to study the long-term effects of GDNF, mouse fetal dopaminergic tissue was transplanted into the ventricles of adult mice and evaluated after 6 months. No surviving dopamine neurons were present in the absence of GDNF. In contrast dopamine neurons developed with GDNF did survive, indicating that GDNF is an essential neurotrophic factor when it comes to long-term dopamine cell survival. More cases have to be assessed in the future in order to strengthen the findings. Thus, transplanted dopamine neurons will be assessed after 3 and 12 months in order to map out when dopamine neurons deprived of GDNF undergo degeneration.

    Fulltekst (pdf)
    FULLTEXT01
  • 25.
    Nookuea, Worrada
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zambrano, Jesús
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Tan, Yuting
    Royal Institute of Technology, Sweden.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Institute of Technology, Stockholm, Sweden.
    Comparison of Mass Transfer Models on Rate-Based Simulations of CO2 Absorption and Desorption Processes2017Inngår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, s. 3747-3752Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    One of the keys available options for the large scale carbon capture and storage is the solvent-based post-combustion capture. Due to the high reactivity between CO2 and aqueous amine solutions, chemical absorption is suitable for capturing the CO2 at low concentration such as from the flue gas. From techno-economic analyses of the CO2 chemical absorption plant, absorber and desorber columns are the main cost of the purchased equipment. Since the process involves complex reactive separations, the accurate calculation of hydrodynamic properties, mass and energy transfer are of importance for the design of the columns. Several studies have been done on the impact of different process and property models on the equilibrium and rate-based simulation of the absorption site. However, the impact study of process and property models on the desorption site are still lacking. This paper performs rate-based simulations of CO2 absorption by Monoethanolamine. The software Aspen Plus was used for the simulations. Different mass transfer models were implemented for the mass transfer calculation in gas and liquid phases. The temperature and concentration profiles along the columns are reported and discussed.

  • 26.
    Norin, Anneli
    Mälardalens högskola, Institutionen för biologi och kemiteknik.
    Coordination Chemistry of Novel Drug Candidates for the Treatment of Iron Overload2007Oppgave
    Abstract [en]

    Iron overload is a serious clinical condition caused by excessive iron in the body, which can be largely prevented by the use of iron-specific chelating agents. At the moment there are only a few chelators in clinical use for the treatment of Fe overload. One of them, and so far the best working one, is desferrioxamine (DFO). This iron chelator has a major disadvantage of being orally inactive and is given by long and frequent subcutaneous infusions (12-24 hours/5-6 days/week) to patients. 1 Consequently, the design of an orally active, nontoxic, selective iron chelator has become a high priority. To design an iron chelator for clinical use, the important factors to consider are metal selectivity and affinity, ligand-metal complex stability, bioavailability and toxicity. The best iron chelator should be highly selective for iron(III) in order to minimize chelation of other biological essential metal ions which could lead to deficiency with prolonged usage. Favouring the Fe (III) oxidation state avoids Fenton chemistry and the production of toxic free radicals. This report deals with complexes of aroylpicolylhydrazines. Chemical and biological testing has established that these molecules function extremely well as iron chelators in vivo. The most effective candidates are more efficient at promoting iron efflux (release of iron) from cells than the existing drug DFO. Although the ligands discussed in this report, are selective for iron, there is no record of how they interact with other essential metal ions (Mn, Co, Ni, Cu and Zn) in our body and it is this that is the topic of this report. It was found that the complexes with H2PPH (N,N’-bis(α-picolinoyl)hydrazine) probably built polymeric complexes and therefore they were almost totally insoluble in all common solvents. The complexes of H2BPH (N-(benzoyl)-N’-(picolinoyl)hydrazine)) were also problematic in terms of insolubility. Another problem was decomposition of the complexes in solution, with resultant precipitation of the ligand and that happened with all of the ligands. The ligand H2TPH formed complexes with Ni and Co, [MII(HL)2] and [MIII(L)2]-, and crystals were grown suitable for x-ray structure studies. The cobalt complex is the first one reported of its kind. There was also crystals grown suitable for x-ray work of a protonated picolylhydrazide and that is also the first crystal structure reported.

    Fulltekst (pdf)
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  • 27.
    Nurkkala, Lasse
    Mälardalens högskola, Institutionen för biologi och kemiteknik.
    Design, Synthesis and Properties of Bipyridine-capped Oligothiophenes for Directed Energy and Electron Transfer in Molecular Electronic Applications2007Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The earliest landmark in computer technology was construction of the Electronic Numerial Integrator and Computer, ENIAC. Computational switching was performed with vacuum tubes and relays, rather large in size, making this computer rather unwieldy. The next milestone came with the integration of transistors into computers as the switching component. Since then, transistors have been miniaturised dramatically, resulting in the amount of components integrated on a computer chip increasing logarithmically with time. The components are nowadays so small and so densely packed that problems with leak currents and cross-talk can arise and the lower limit for transistor size will soon be reached. In order to meet increasing demands on the size and performance of electronics, a new paradigm is due – the molecular electronics approach.

    Oligothiophenes have been shown to possess the physical and chemical characteristics required for electron/energy transport in molecular systems. However oligothiophenes must be electronically coupled to other components within a molecular circuit for them to be functional. In this work, different modes of incorporation of [2,2’]-bipyridinyl functionalities onto the ends of prototypic oligothiophene wires have been examined. The bipyridine connectors allow complexation to metal centres which can then function as a source or sink of electrons in the circuit. Ruthenium tris-bipyridine complexes, in particular, possess interesting electrochemical and photophysical characteristics, making them suitable for use in molecular electronics.

    This thesis reports synthetic strategies to a range of novel ligands based on the [2,2’]-bipyridinyl system, together with a study of the redox and fluorescence properties of their ruthenium tris-bipyridine complexes. The mode of connection between the chelating bipyridine and the first member of the oligothiophene chain was found to have a profound effect upon the fluorescence lifetimes and intensities of the resulting complexes. The discovery of complexes exhibiting long and intense fluorescence (a requirement for directed electron/energy transfer within molecular networks) thus forms an important design element in future prototypes.

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  • 28.
    Palm, Anders
    et al.
    Greater Stockholm Fire Brigade, Stockholm, Sweden..
    Kumm, Mia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Ingason, Haukur
    SP Fire Res, SP Tech Res Inst Sweden, Borås, Sweden.;Lund Univ, Lund, Sweden..
    Full Scale Firefighting Tests in the Tistbrottet Mine2016Inngår i: Fire technology, ISSN 0015-2684, E-ISSN 1572-8099, Vol. 52, nr 5, s. 1519-1537Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The paper describes full-scale fire-fighting tests performed in an underground mine. A total of six different methods to fight a full scale fire in a mine tunnel were tested. The methods involved different fire-fighting equipment but were comparable regarding fundamental conditions such as length of response-route, fire-fighting set-up, and smoke and fire size. The aim was to compare different equipment and methods to reach and eventually extinguish the fire. Fire fighters using breathing apparatus (BA) were monitored regarding air consumption, movement speed and local actions and decisions. The results are presented and analyzed in respect to fire-fighting efficiency, front BA operations including moving speed and performed actions, as well as the time to successfully put out the fire. Measurements of heat release rates, temperatures and moving speeds are given in order to quantify the efficiency of the operation. Results indicate that a timespan of 15-30 min is needed for the firefighters to reach the fire source and achieve the extinguishing criteria in five of the tests. The standard equipment and nozzles shows good performance in the tests. A limiting factor on the firefighter's endurance is the amount of air that is available. As a result from these findings the endurance of BA-teams could improve if focus is put on team organization, lightweight equipment and air supply.

  • 29.
    Pettersson, Hanna
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Törnvall, Elin
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Efterbehandling av biogödsel: Ett försök med avskiljning och uppsamling av kväve och vatten genom ammoniakstripping i en efterhygieniseringsprocess2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    During this master thesis, the possibility of ammonia removal from digestate in combination with after hygienization has been investigated. The aim of the work was to see how much ammonia that could be removed but also the properties of other process parameters such as TS/VS content, pH and alkalinity of the digestate. It was also of interest to study the energy balances for a process that combines ammonia stripping with after hygienization. The purpose of hygienization in a biogas plant is to kill pathogens. To study ammonia stripping combined with after hygienization, a prototype of an ammonia stripper was built in a laboratory. The digestate was heated to the hygienization temperature of 70 °C and air was led through with the help of a peristaltic pump by the end of the system. Condensate was trapped in a bottle by cooling the tube and the gases were brought to another bottle containing 1 M sulfuric acid. Ammonia and sulfuric acid reacted and formed ammonium sulfate. The process was also tested with closed system using vacuum to decrease the boiling point and thereby create more condensate. The results from the experiments showed that with an air stripping process most of the ammonium was trapped in the sulfuric acid while with a vacuum process more ammonium was trapped in the condensate. The most important parameters to achieve a good ammonia removal were air flow and time. With the vacuum system, more condensate was removed. The removal of condensate could make it possible to recirculate process fluid from the stripping process and thereby save energy in the centrifugation part which is used to create a solid part of the bio digestate. It was concluded from the experiments that air stripping is more effective when it comes to ammonium recovery. The process could be improved by using higher air flow which could decrease the time to less than one hour, which is the desired hygienization time. However, it is desired to keep the pump flow as low as possible since it is energy consuming. A chemical increase of the pH would also be of interest to try since previous tests showed a strong correlation between high pH-value and good ammonia stripping. More tests overall are of interest to ensure a reliable result. Still, the combination of after-hygienization and ammonia stripping would contribute to a better environment and a sustainable agriculture with a natural and nutritious digestate.

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  • 30.
    Saarinen, Gabrielle
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Development of Synthetic Routes for Preparation of 2,6-Disubstituted Spiro[3.3]heptanes.2009Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    2,6-Disubstituted spiro[3.3]heptanes were synthesized to investigate and develop synthetic methods for preparation of these compounds. Possibilities for introducing different functionalities like nitriles and sulfonamides were also investigated.

     

    Synthetic routes presented describe successive [2+2] cycloadditions between dichloroketene and olefins to give the sought after spiro compounds with low to moderate yields throughout the multi-step synthesis. [2+2] Cycloadditions offered low turnovers and chromatography was required for purification.

     

    A synthetic route with cyclisations through double substitution reactions between di-electrophiles and di-nucleophiles resulting in a 2,6-disubstituted spiro[3.3]heptane is also described. This multi-step synthesis offered higher turnover and yields and often there was no need for purification through chromatography.

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  • 31.
    Sadeghi, Mohammad
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Technology development institute (ACECR), Tehran, Iran.
    Dorodian, M.
    Technology development institute (ACECR), Tehran, Iran.
    Rezaei, M.
    Technology development institute (ACECR), Tehran, Iran.
    Synthesis and Characteristic of Precipitated Nano-Silica2013Inngår i: Journal of Advances in Chemistry, ISSN 2321-807X, Vol. 6, nr 1, s. 917-922Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    The reaction of precipitation of amorphous silicon dioxide from aqueous solution of sodium silicate and sulfuric acid has been studied. The factors affecting the precipitation process of the sodium silicate solution such as sodium silicate concentration and addition of anionic surfactant (sodium dodecyl sulfate, SDS) on particle size, size distribution and degree of agglomeration of the precipitated silica were examined. The precipitation of silica from the produced sodium silicate solution was carried out using sulfuric acid at pH 7. Scaning electron microscope (SEM), transmission electron microscope (TEM) and Dynamic light scattering (DLS) have been used for characterization of the produced nano-silica. The surface area of silica was tested by oil absorption method according to ASTM standard. Results showed that the particle size of the precipitated silica gel was decreased with increasing Na2SiO3 and SDS concentrations and Particle size of about 44nm can be achieved at 20% Na2SiO3 and 200ppm SDS. But with decreasing particle size, degree of agglomeration also increased.

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  • 32.
    Salman, Chaudhary Awais
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Integration of thermochemical processes with existing waste management industries to enhance biomethane production2018Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In most waste management industries, waste is separated into different fractions, each of which is treated with suitable processes. Established technologies such as waste combustion for combined heat and power (CHP) production and biomethane production through anaerobic digestion (AD) of biodegradable waste work fine as standalone processes. However, specific issues are associated with these established standalone waste-to-energy (WtE) processes. For example, traditional CHP plants have high overall energy efficiencies, but lower electrical efficiencies, and their heat outputs are dependent on local demand and seasonal variations. Similarly, biodegradable waste typically sent for AD contains lignocellulosic or green waste. Due to the lower biodegradability of lignocellulosic waste, only a proportion is sent for digestion, while the rest is incinerated, increasing transportation costs. Increased benefits from the perspective of energy and economics can be achieved by integrating new WtE processes with existing technologies.

     

    This thesis aims to design energy-efficient and profitable biorefineries by integrating existing waste management facilities with the thermochemical treatment of waste. A systems analysis of two process integration concepts has been studied through modelling and simulation. The first analysis is of the process integration of gasification with existing CHP plants, and the second is the process integration of pyrolysis with an existing AD plant. For integration of gasification with a CHP plant, reasonable operational limits of the CHP plant have been assessed and compared by integrating three types of gasifier, and the most technically and economically integrated processes have been identified. In the case of integration of pyrolysis with AD, a new process configuration is presented that couples the AD of biodegradable waste with the pyrolysis of lignocellulosic waste. The biochar obtained from pyrolysis is added to a digester as an adsorbent to increase the biomethane production. In addition, the vapors produced by the pyrolysis process are converted to biomethane. Two different conversion processes are compared to convert pyrolysis vapors to biomethane, catalytic methanation and biomethanation. 

     

    The results demonstrate that process integration can contribute to reducing the cost of biomethane production through integration of gasification and pyrolysis with CHP and AD, respectively. The process integration can also utilize infrastructure and products from existing industries and increase the overall process efficiencies. Of the gasifiers studied, the dual fluidized bed gasifier produces more biomethane than the circulating bed and entrained flow gasifiers when retrofitted with an existing CHP plant with up to 85% efficiency. The CHP–gasification integration is capable of producing more biomethane during low heat demand seasons without disturbing the operation of the CHP operation. A gasifier with a flexible capacity can be integrated with the CHP to produce biomethane without affecting the heat production of the CHP. From an economic perspective, the dual-bed gasifier requires lower capital investment and is therefore more profitable, because it requires less equipment than the circulating fluidized and entrained flow gasifiers. The integration of pyrolysis with the AD process can almost double biomethane production comparison with standalone AD process, increasing efficiency to 67%. The integration is an attractive investment when catalytic methanation of syngas is used rather than biomethanation of syngas. The catalytic methanation route has an economic rate of return of 16%, with a six-year payback period.

     

    The main conclusion drawn from this thesis is that production of biomethane can be enhanced through process integration of gasification with the CHP plant and of pyrolysis with AD. However, the increase in biomethane production also increases the demand for waste at the integrated biorefinery. Hence, the capacity of the gasifier and pyrolysis process will be decisive in determining the level of integration of the biorefineries.

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  • 33.
    Skvaril, Jan
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Near-Infrared Spectroscopy and Extractive Probe Sampling for Biomass and Combustion Characterization2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Biomass is characterized by highly variable properties. It can be converted to more valuable energy forms and products through a variety of conversion processes. This thesis focuses on addressing several important issues related to combustion and pulping.

    Experimental investigations were carried out on a biomass-fired industrial fluidized-bed boiler. The observed combustion asymmetry was explained by an imbalance in the fuel feed. Increased levels of carbon monoxide were detected close to boiler walls which contribute significantly to the risk of wall corrosion.

    Moreover, extensive literature analysis showed that near-infrared spectroscopy (NIRS) has a great potential to provide property information for heterogeneous feedstocks or products, and to directly monitor processes producing/processing biofuels in real-time. The developed NIRS-based models were able to predict characteristics such as heating value, ash content and glass content. A study focusing on the influence of different spectra acquisition parameters on lignin quantification was carried out. Spectral data acquired on moving woodchips were found to increase the representativeness of the spectral measurements leading to improvements in model performance.

    The present thesis demonstrates the potential of developing NIRS-based soft-sensors for characterization of biomass properties. The on-line installation of such sensors in an industrial setting can enable feed-forward process control, diagnostics and optimization.

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  • 34.
    Skvaril, Jan
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Odlare, Monica
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Multivariate analysis models for wood properties combined with Open Modelica model for process performance monitoring2015Inngår i: IFAC Proceedings Volumes (IFAC-PapersOnline), 2015, Vol. 48:1, s. 898-899Konferansepaper (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    To perform advanced model based control it is important to know what is fed into a system such as a waste or biomass fired boiler or a pulp digester. In this paper, we present correlations between the lignin content of different types of wood chips and their Near-infrared (NIR) spectra. The Principal Component Regression (PCR) method is used for deriving the correlation, as well as selecting certain wave lengths. Analysis is made including different parts of the spectra in the wave length range 700 – 2500 nm. The model is then used as input to an Open Modelica pulp digester model to tune the reactivity constant of the dissolution of lignin. The lignin content of wood-chips is determined on-line through the NIR measurement at the feed to the digester. Simulations are carried out to determine the content of residual lignin on fibers at the exit (continuous digester) or at the end of a cook (batch digester). By comparing the deviation between predicted values and actual measured values the reactivity constant of the lignin is determined. The regression can be made to the NIR spectrum aside of the lignin content as such. The original content of lignin together with reactivity may then be used for optimized on-line control of the digester. It can also be used for diagnostic purposes with regard to process issues like hang-ups or channeling, as well as possible sensor faults and data reconciliation.

  • 35.
    Skvaril, Jan
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Applications of near-infrared spectroscopy (NIRS) in biomass energy conversion processes: A review2017Inngår i: Applied spectroscopy reviews (Softcover ed.), ISSN 0570-4928, E-ISSN 1520-569X, Vol. 52, nr 8, s. 675-728Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Biomass used in energy conversion processes is typically characterized by high variability, making its utilization challenging. Therefore, there is a need for a fast and non-destructive method to determine feedstock/product properties and directly monitor process reactors. The near-infrared spectroscopy (NIRS) technique together with advanced data analysis methods offers a possible solution. This review focuses on the introduction of the NIRS method and its recent applications to physical, thermochemical, biochemical and physiochemical biomass conversion processes represented mainly by pelleting, combustion, gasification, pyrolysis, as well as biogas, bioethanol, and biodiesel production. NIRS has been proven to be a reliable and inexpensive method with a great potential for use in process optimization, advanced control, or product quality assurance.

  • 36.
    Steen, Robert
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Molecular Electronic Devices based on Ru(II) Thiophenyl Pyridine and Thienopyridine Architecture2010Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    According to the famous axiom known as Moore’s Law the number of transistors that can be etched on a given piece of ultra-pure silicon, and therefore the computing power, will double every 18 to 24 months. However, around 2020 hardware manufacturers will have reached the physical limits of silicon. A proposed solution to this dilemma is molecular electronics. Within this field researchers are attempting to develop individual organic molecules and metal complexes that can act as molecular equivalents of electronic components such as wires, diodes, transistors and capacitors.

    In this work we have synthesized a number of new bi- and terdentate thiophenyl pyridine and pyridyl thienopyridine ligands and compared the electrochemical, structural and photophysical properties of their corresponding Ru(II) complexes with Ru(II) complexes of a variety of ligands based on 6-thiophen-2-yl-2,2'-bipyridine and 4-thiophen-2-yl-2,2'-bipyridine motifs. While the electrochemistry of the Ru(II) complexes were similar to that of unsubstituted [Ru(bpy)3]2+ and [Ru(tpy)2]2+, substantial differences in luminescence lifetimes were found. Our findings show that, due to steric interactions with the auxiliary bipyridyl ligands, luminescence is quenched in Ru(II) complexes that incorporate the 6-thiophen-2-yl-2,2'-bipyridine motif, while it was comparable with the luminescence of [Ru(bpy)3]2+ in the Ru(II) complexes of bidentate pyridyl thienopyridine ligands. The luminescence of the Ru(II) complexes based on the 4-thiophen-2-yl-2,2'-bipyridine motif was enhanced compared to [Ru(bpy)3]2+ which indicates that complexes of this category may be applicable for energy/electron-transfer systems.

    At the core of molecular electronics is the search for molecular ON/OFF switches. Based on the ability of the ligand 6-thiophen-2-yl-2,2'-bipyridine to switch reversibly between cyclometallated and non-cyclometallated modes when complexed with Ru(tpy) we have synthesized a number of complexes, among them a bis-cyclometallated switch based on the ligand 3,8-bis-(6-thiophen-2-yl-pyridin-2-yl)-[4,7]phenanthroline, and examined their electrochemical properties. Only very weak electronic coupling could be detected, suggesting only little, if any, interaction between the ruthenium cores.

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  • 37.
    Svensson, Sara
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Minimizing the sulphur content in Kraft lignin2008Independent thesis Advanced level (degree of Magister), 20 poäng / 30 hpOppgave
    Abstract [en]

    The aim of this project is to investigate the possibilities of minimizing the sulphur content in Kraft lignin. Kraft lignin contains about 1.5 to 3% sulphur. The sulphur is believed to be present in lignin as inorganic sulphur, as elemental sulphur, as adsorbed polysulphide and/or as organically bound sulphur. For the determination of these different types of sulphur components, different approaches and methods were used. For the determination of inorganic sulphur, lignin was washed with water at pH 6 and pH 2 and the wash waters were analysed with ion chromatography (IC). For the determination of total sulphur content in the lignin, two methods were used; Schöniger combustion followed by ion chromatography (IC) and wet digestion followed by inductively coupled plasma (ICP). The elemental sulphur content in water-extracted lignin was determined after n-pentane extraction. ICP analysis was performed on the washed lignin.

    Calcium present in the lignin may bind polysulphides and thus be a source of the observed sulphur. The lignin was thus ion-exchanged to remove any calcium. To further investigate how the sulphur content in lignin can be decreased, two different types of reactions were performed on lignin; oxidation and reduction. The oxidation reactions were made in sodium hydroxide with oxygen at different temperatures and time on both original and water-extracted lignin. The reduction reactions were made on water-extracted lignin with Raney nickel in three different solvent systems: methanol: water, acetone: water and sodium hydroxide.

     

    The original lignin contained 2.6% sulphur as determined by ICP. Washing lowered the content to 1.85% sulphur. By n-pentane extraction the elemental sulphur was lowered to a level of 1.82% sulphur, which was considered to be organically bound sulphur. Neither the ion exchange nor the oxidation lowered the sulphur content significantly.

     

    The reduction reactions successfully the organically bound sulphur from 1.82% to a level of 0.54%.

     

    The relative distribution of the sulphur content in the studied softwood lignin was as follows: about 29% as inorganic sulphur, about 1% as elemental sulphur and approximately 70% as organically bound sulphur, of which 49% could be removed by Raney nickel.

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  • 38.
    Sydkull, Sara
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Optimization of biomolecular techniques for detection of nitrite-oxidizing bacteria2009Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Nitrification is a natural occurring, oxidative process which is essential for plants´ ability to take up nitrogen in the form of nitrate. The oxidation is divided into two steps. First ammonia is oxidized to nitrite by ammonia-oxidizing bacteria (AOB) or archaea (AOA) and then the nitrite is further oxidized to nitrate by nitrite-oxidizing bacteria (NOB). The enzyme used by NOB for the oxidation is nitrite oxidoreductase (nxr). One of few bacteria that catalyze this reaction is Nitrobacter sp.

    The purpose of this study has been to optimize the detection of Nitrobacter in samples of activated sludge from municipal wastewater treatment plants (WWTPs) in Eskilstuna and Västerås (Sweden). This was done by PCR, cloning and sequencing. Primers used were nor F/nor R that are specific for the functional gene encoding nxr. This optimization has been compared to a different PCR-system where nor F/nor R were exchanged for another primerpair consisting of a 16S rDNA-primer (NIT3), which was specific for Nitrobacter and a universal 16S-primer (U2, Rit388). In addition to this, a semi quantitative analyze has also been conducted.

    The result of the study was two PCR-programmes, one optimized for each set of sludge samples. The quantitative analysis showed that the concentration Nitrobacter in the sludge samples was approximately the same as a pure culture, which was used as a positive control and contained ~104 CFU/ml.

    Cloning and sequencing revealed the presence of 3 different Nitrobacter. Surprisingly half of the clones from one of the Västerås samples, taken in December, were most likely Methylibium petroleiphilum. The matter of fact that we were able to detect this bacterium with primers specifically designed for Nitrobacter made this discovery even more interesting. With NIT3/U2 Methylocella sp. was also detected in samples from Västerås, which confirmed the presence of methylotrophic bacteria in the Västerås samples.

     

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  • 39.
    Tengstrand, Therése
    Mälardalens högskola, Institutionen för biologi och kemiteknik. Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Development of Methods for Characterization of Prostate Specific Antigen in Urine2007Oppgave
    Abstract [en]

    Prostate cancer is the most detected cancer in males and one of the leading causes of cancer mortality in the western society. Prostate Specific Antigen (PSA) is since the 1980´s widely used as a serum marker but can not distinguish between prostate cancer and benign prostate hyperplasia. PSA is a glycoprotein with a molecular weight of 30 kDa and consists of an active 237 amino acid residues polypeptide with five disulphide bonds and approximately 7-12 % carbohydrates. The aim of the project was to develop an immunochromatographic test for measuring the total concentration of PSA in urine and to verify, by using size exclusion chromatography, if PSA in urine was free or complexed with other proteins. However, the first issue was to deal with the variable urine composition and the occurrence of precipitate in urine which can bind proteins. Six different immunochromatographic test systems were developed and the concentration of PSA was measured in urine specimens from normal individuals and from patients with prostate cancer by using two selected systems. The most sensitive immunochromatographic system showed a detection limit of 1.2 ng/L which is 130 times more sensitive than presently available commercially enzyme immunoassays. The precipitates in urine were dissolved by pH-adjustment and addition of chelator and detergent. Only 0.5% PSA was detected in the supernatant of centrifuged urine in comparison to when the precipitates where dissolved and these findings confirm that PSA in urine is in precipitate. The median concentration in normal male urine was 106µg/L. The highest value of 991µg/L was obtained in urine from a patient with prostate cancer but several of the urine specimens from patients showed non-detectable values. Four normal and patient urine specimens were separated by size exclusion chromatography and the fractions were measured by two immunochromatographic test systems. For all specimens a single peak was eluted in the same position which was consistent with a 30kDa molecular weight protein and no larger complex of PSA could be found. However, it was found that measurable PSA during storage in the fraction tubes could disappear rapidly.

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  • 40.
    Thirugnanam, Vasanthakumar
    Mälardalens högskola. Mälardalens högskola, Akademin för hälsa, vård och välfärd. Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Effect of combined treatment with R-(+)-methanandamide and chemotherapeutic drugs in mantle cell lymphoma and chronic lymphocytic leukemia: MCLIndependent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Mantle cell lymphoma (MCL) is a non-Hodgkin B-cell lymphoma with very bad prognosis. The genetic hallmark of MCL, is the translocation t(11;14)(q13;q32) which leads to overexpression of cyclin D1, a D-type cyclin that is not usually expressed at high levels in normal B lymphocytes.

     

    Previous studies indicate that cannabinoid receptors are expressed in lymphoma and have shown that lymphoma cell death is induced as a result of exposure to cannabinoids (ligands).

     

    The aim of this diploma work was to combined cytostatics with the cannabinoid receptor ligand R (+)-Methanandmide (R-MA). Our data suggest that combination treatment with cytostatics and R-MA induces synergistic effects in most cases.

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  • 41.
    Xinhai, Yu
    et al.
    East China University of Science and Technology.
    Hongliang, Li
    East China University of Science and Technology.
    Shan-Tung, Tu
    East China University of Science and Technology.
    Yan, Jinyue
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Pt-Co catalyst-coated channel plate reactor for preferential CO oxidation2011Inngår i: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 36, nr 5, s. 3778-3788Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    To achieve preferential CO oxidation, a PteCo catalyst-coated channel plate reactor (CCPR)was produced via conventional mechanical milling and catalyst coating. The proposedreactor performed well under a wide range of operating temperatures and providedsatisfactory results at low temperatures (CO concentrations of 1e10 ppm at 413e443 K and1e50 ppm at 413e453 K). In the proposed CCPR, significant deactivation was not observedduring continuous operation for 100 h. In addition, the reactor exhibited excellent toleranceto undesirable conditions, including reaction temperature runaway and feedingstream failure. Characterisation results indicated that the catalytic activity of the proposedCCPR was high due to the formation of Pt3Co intermetallic compounds and nanoscalemetal particles. The capacity per channel of the proposed CCPR was approximately 50e100times greater than those of conventional microchannel reactors; thus, problems associatedwith excessive reactors were significantly reduced. In general, the results indicated thatCCPR has great potential in the small-scale production of hydrogen for fuel cells.

  • 42.
    Yan, Jinyue
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Inst Technol. KTH, Sweden.
    Chou, Siaw-Kiang
    Natl Univ Singapore, Singapore.
    Desideri, Umberto
    Univ Pisa, Pisa, Italy.
    Lee, Duu-Jong
    Natl Taiwan Univ Sci & Technol, Taiwan.
    Transition of clean energy systems and technologies towards a sustainable future (Part I)2015Inngår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 160, s. 619-622Artikkel i tidsskrift (Fagfellevurdert)
  • 43.
    Yu, Xinhai
    et al.
    E China Univ Sci & Technol, China.
    Yang, Jie
    Univ Shanghai Sci & Technol, China.
    Lu, Haitao
    E China Univ Sci & Technol, China.
    Tu, Shan-Tung
    E China Univ Sci & Technol, China.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Inst Technol, Stockholm, Sweden.
    Energy-efficient extraction of fuel from Chlorella vulgaris by ionic liquid combined with CO2 capture2015Inngår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 160, s. 648-655Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Algae-sourced feedstocks remain confined to commercialization because of the high cost and energy consumption of biomass cultivation and feedstock extraction. In this study, to reduce the energy consumption required for algae extraction, experiments with Chlorella vulgais extraction by ionic liquids (ILs) combined with CO2 capture were conducted considering that captured CO2 by ILs can compensate the energy consumption of extraction. The results showed that the addition of CO2 to [BMIM][BF4] increased the lipid yield of Chlorella vulgaris from 68.0% to 75.6%. The properties of synthesized biodiesel from C vulgaris lipids met the UNE-EN 14214 European biodiesel standard except for oxidative stability. Protein denaturation and degradation were found during the lysis of algae cells. Approximately 82.2 wt.% of the total extracted proteins could be precipitated during both algae lysis and supernatant liquid drying. A microalgae-to-biofuel route including C vulgaris extraction and CO2 capture was proposed that involves wet algae input and delivery outputs of water, biodiesel, pyrolysis oil, proteins, sugars, biogas and glycerol. Fossil energy ratios (FER) based on the overall energy balance were 3.30 (n = 1, n is the volume ratio of IL to wet algae) and 3.84 (n = 2) for [BMIM][BF4] with CO2 capture, approximately 2.5 times those based on commercially available technologies. The possibilities of synthesizing novel ILs that show both high CO2 absorption and good abilities in cell wall breakage are discussed. More progress is greatly needed to reduce IL recovery loss. (C) 2015 Elsevier Ltd. All rights reserved.

  • 44.
    Zaidi, Syed Faraz Ali
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Sudthanom, Juthatip
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    To Analyze The Relationship between BOD, Nitrogen And Phosphorus Contents at Constant Dissolved Oxygen Concentration In Municipal Wastewater Treatment2011Independent thesis Advanced level (degree of Master (One Year)), 15 poäng / 22,5 hpOppgave
    Abstract [en]

    In this report, the application of Principle Component Analysis (PCA) and Partial Least Square (PLS)  regression analyzing methods used to understand the relationship of interdependent loads in municipal wastewater treatment plant. Two different wastewater treatment plants were chosen for analysis of  the relationship between interdependent loads. Firstly, the collected data of incoming wastewater and outgoing water from both Västerås and Eskilstuna wastewater treatment plants were analyzed to find some relationship or correlation between contents and compare the data of both the plants. Secondly, the correlated contents were used to generate the regression model for predicting the value in the future, in this report we have focussed only on ammonium nitrogen value for regression model. The PCA study shows the variation between incoming and outgoing wastewater’s characteristics  given by  Västerås and Eskilstuna plant.   

    Fulltekst (pdf)
    Analysis Report of Municipal WWTP
  • 45.
    Zhang, Guoqiang
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Yan, Jinyue
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Jin, Hongguang
    Chinese Acad Sci, Inst Engn Thermophys, Beijing.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Integrated black liquor gasification polygeneration system with CO2 Capture in pulp and paper mills to produce methanol and electricity2011Inngår i: International Journal of Green Energy, ISSN 1543-5075, E-ISSN 1543-5083, Vol. 8, nr 2, s. 275-293Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Based on KAMa pulp and paper mill, a polygeneration system integrated with a black liquor gasifier is proposed. The effects of CO2 captured by oxygen-fuel combustion and Selexol absorption on the performance of the polygeneration system are studied in terms of both thermodynamic performance and cost assessment. Using the Aspen Plus simulator, the performance of the studied polygeneration systems are analyzed from the perspectives of the first and second laws of thermodynamics. Compared with the reference system, the first law efficiency of the polygeneration system increased from 15.7% to 29.3%, with an investment increment of 17.9%. The investment incremental rates for CO 2 capture by oxyfuel combustion and Selexol absorption are 15.1% and 16.7%, respectively. Energy penalty due to CO2 capture and compression is 0.61 MJ electricity/kg CO2, avoided in the oxygen-fuel method at a cost of $29.6/tonne CO2. However, energy penalty can reach 1.03 MJ product (electricity and methanol) per kg CO2, avoided in the Selexol absorption CO2 capture process at a cost of $46.0/tonne CO2.

  • 46.
    Ågren, Joakim
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Utveckling av analysmetoder för en tillämpning inom beredskapsdiagnostik2007Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Bacillus anthracis is a risk class III organism and needs to be handled inside a biosafety level 3-laboratory. A major problem when working with airborne, spore-forming bacteria like B. anthracis are the hazardous aerosols created when using an automated DNA-extraction method to prepare samples suspected to contain the organism. This study has therefore evaluated the possibility of enclosing a DNA-extraction-robot inside an air tight container (glove box). A prototype of a class III safety cabinet (also known as a glove box) was designed and built to enclose a BioRobot EZ1 from Qiagen. The purpose of this prototype was to evaluate the measurements needed to and also the feasibility of working with the robot inside the cabinet. During the manual DNA-extractions, there was some contamination found on the glove box gloves, probably due to the significantly lowered dexterity that was seen with the thick gloves. The enclosing of the robot revealed no obstacles as the machine was very easy to operate. In addition, protocols have been created for the operation of a transportable class III safety cabinet from Germfree available at SVA. The protocols include the different pressure tests that needed before every experiment take place and also decontamination steps before and after each run. Bacillus cereus was used as a model organism for different DNA-extractions, i.e. automated and manual extractions. The extracted DNA was analysed by real-time polymerase chain reaction (PCR). DNA was also extracted and analysed from B. cereus-spores. When using a manual DNA-extraction kit, B. cereus-DNA was detected at the femtogram level, i.e. 10-15 g DNA / PCR. When using the automated BioRobot EZ1, detection level was found to be at 10-16 g DNA / PCR. The PCR-efficiency for the manual kit was 89-90 % for all samples, whereas with the EZ1, efficiency was 99 %, showing the strengths of the magnetic bead separation used by the machine. A novel PCR-machine, the AlphaHelix QuanTyper™, was evaluated and compared to an ABI 7500 with regards to efficiency, speed and consistency. The QuanTyper™ was found to be superior in ramping speeds, performing a 40-cycle real-time PCR-run with melting point analysis in only 14 minutes. The fastest run accomplished on the ABI 7500 took 1 h 40 min. A ready made master mix for PCR was used for most tests (Platinum® SYBR® Green qPCR SuperMix-UDG), but faster and more robust enzymes are available and further studies need to be performed on the QuanTyper™ to fully evaluate the platform. Three target genes in Bacillus anthracis-DNA were analysed in only 38 minutes with efficiencies between 96-104 % for the virulence plasmids and detection at femtogram amount of DNA. This master thesis has addressed rapid pathogen-detection with automated DNA-extraction and novel PCR-technology, coupled with a strong biosafety aspect. The thesis will hopefully contribute to the surprisingly small area of biosafety and safety cabinet research.

    Fulltekst (pdf)
    FULLTEXT01
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