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Optimising banking procedures for non-viable skin and dermal plantsHuang, Qizhi January 2002 (has links)
No description available.
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Modulation of phase behaviour and structures of phospholipid model membranes by organic solutesYu, Zhi Wu January 1995 (has links)
No description available.
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Co-digestion of hog manure with glycerol to boost biogas and methane productionWohlgemut, Oswald 21 January 2009 (has links)
The use of off-farm materials as amendments in anaerobic digestion of manure is an interesting option due to the benefits of boosting biogas production, and making the process more economical for the farmer. The addition of varying amounts of glycerol, which is a by-product of biodiesel production, was used as an amendment to anaerobic digestion of hog manure in lab-scale tests. The use of 2% glycerol produced the greatest amount of methane and biogas, however stabilization time was high, and the digestion of nutrients in the manure decreased. The addition of 4% glycerol resulted in an overloading of COD and digester failure. The addition of 1% glycerol resulted in a doubling of the methane and biogas production and the acclimation period was quite short, while the effluent quality remained good. There were no detrimental effects of using crude glycerol observed compared to using pure glcyerol. Batch tests also showed that smaller additions of glycerol (0.5%, 1%) produced the highest methane yields and were recommended as good co-substrates for anaerobic digestion with hog manure. / February 2009
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Effects of anode modification on the improved performance of organic solar cells based on poly (3-hexylthiophene): FullereneHuang, Yen-liang 17 July 2007 (has links)
We investigated the different percentage of glycerol or ethylene glycol doped into PEDOT:PSS as anode buffer layer in OSC. The electrical, optical and physical properties of PEDOT:PSS were measured before and after adding glycerol or ethylene glycol. Their optical transparency was almost the same by UV-Vis spectrophotometer. Their HOMO value, measured by PESA, was around 5.1eV. Modified PEDOT:PSS with proper concentration addition increased its conductivity. Finally, surface roughness of PEDOT:PSS layer increased with higher concentration of addition resulted in bad film-forming from spin coating process.
We fabricated polymer solar cells with modified PEDOT:PSS as anode buffer layer. The devise was consisted of ITO/PEDOT:PSS (different doping concentration of glycerol or ethylene glycol ) /P3HT:PCBM /Al and measured device parameter of solar cell with sunlight simulation of AM1.5G 100mW/cm2 . We found that improvement of power conversion efficiency of polymer solar cell from 2% to 3% and short-circuit current was improved for 32%, with modified PEDOT:PSS as anode buffer layer.
We suggested that the improved short-circuit current was originated from increased conductivity of PEDOT:PSS that was modified by glycerol or ethylene glycol. Finally power conversion efficiency of polymer solar cell was increased with modified.
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Development of sustainable microbial fermentation strategies for the production of medium-chain length polyhydroxyalkanoates (mcl-PHAs) from biodiesel derived glycerolSharma, Umesh January 1900 (has links)
Bio-plastics have emerged as a promising alternative to conventional petrochemical derived plastics particularly over the past few decades. Numerous production methods for bio-plastics have been researched; however, work remains towards developing a commercially viable and economical process. The purpose of this research was to develop a sustainable fermentation strategy for production and scale-up of medium-chain length polyhydroxyalkanoates (mcl-PHAs), or bio-plastics, using a novel strain of the gram negative bacterium Pseudomonas putida, LS46, with biodiesel derived waste glycerol (WG) as feedstock. Experiments were conducted to gain a basic understanding of the general growth patterns exhibited by LS46. Thereafter, flask-batch experiments were conducted to study effects of variation in media conditions upon cell biomass production and mcl-PHA accumulation. Subsequently, optimal medium conditions observed within flasks were scaled-up and employed in the operation of a pilot-scale fermenter to increase production capacity for mcl-PHAs. It was concluded that mcl-PHA production at commercial levels could be viable with advanced process optimization. / October 2015
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Co-digestion of hog manure with glycerol to boost biogas and methane productionWohlgemut, Oswald 21 January 2009 (has links)
The use of off-farm materials as amendments in anaerobic digestion of manure is an interesting option due to the benefits of boosting biogas production, and making the process more economical for the farmer. The addition of varying amounts of glycerol, which is a by-product of biodiesel production, was used as an amendment to anaerobic digestion of hog manure in lab-scale tests. The use of 2% glycerol produced the greatest amount of methane and biogas, however stabilization time was high, and the digestion of nutrients in the manure decreased. The addition of 4% glycerol resulted in an overloading of COD and digester failure. The addition of 1% glycerol resulted in a doubling of the methane and biogas production and the acclimation period was quite short, while the effluent quality remained good. There were no detrimental effects of using crude glycerol observed compared to using pure glcyerol. Batch tests also showed that smaller additions of glycerol (0.5%, 1%) produced the highest methane yields and were recommended as good co-substrates for anaerobic digestion with hog manure.
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Co-digestion of hog manure with glycerol to boost biogas and methane productionWohlgemut, Oswald 21 January 2009 (has links)
The use of off-farm materials as amendments in anaerobic digestion of manure is an interesting option due to the benefits of boosting biogas production, and making the process more economical for the farmer. The addition of varying amounts of glycerol, which is a by-product of biodiesel production, was used as an amendment to anaerobic digestion of hog manure in lab-scale tests. The use of 2% glycerol produced the greatest amount of methane and biogas, however stabilization time was high, and the digestion of nutrients in the manure decreased. The addition of 4% glycerol resulted in an overloading of COD and digester failure. The addition of 1% glycerol resulted in a doubling of the methane and biogas production and the acclimation period was quite short, while the effluent quality remained good. There were no detrimental effects of using crude glycerol observed compared to using pure glcyerol. Batch tests also showed that smaller additions of glycerol (0.5%, 1%) produced the highest methane yields and were recommended as good co-substrates for anaerobic digestion with hog manure.
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The synthesis and physical properties of selected triacylglycerolsGriffiths, David John January 1985 (has links)
The study of triacylglycerol interactions in the solid phase and their behaviour during crystallisation requires the availability of individual triacylglycerols of proven positional and structural purity. The aim of this work was to prepare some specific triacylglycerols and to examine their crystallisation behaviour as individual samples and in binary mixtures with each other. The first part of this thesis details the synthesis of glycerol 1-stearate 2-caprate 3-palmitate, glycerol 1-stearate 2-oleate 3-palmitate, glycerol 1-stearate 2-elaidate 3-palmitate, glycerol 1-stearate 2,3-dimyristate and glycerol 1,3-dipalmitate 2-laurate. The unsaturated acids used were isolated from olive oil and modified where required. Methods of analysis for quantitative purity determination are given. The second part of the thesis involves the examination of the selected triacylglycerols by methods of X-ray powder diffraction and differential scanning calorimetry. The triacylglycerols prepared as described were supplemented by lipid samples from other sources [glycerol 1-stearate 2-laurate 3-myristate, glycerol 1-stearate 2-myristate 3-laurate, glycerol 1-palmitate 2-stearate 3-oleate, glycerol 1-palmitate 2,3-dielaidate, glycerol 1,2,3-triarachidate, glycerol 1,2,3-triplamitate, glycerol 1, 2,3-tristearate and cocoa butter]. The polymorphic forms of samples prepared from solvent and from thermal conditioning were obtained. Five pairs of the triacylglycerols were chosen for examination as binary mixtures. The preparation methods and result detailed and summarised in temperature vs. composition (phase) diagrams.
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Produção de glicerol quinase em Pichia pastoris /Aizemberg, Raquel. January 2011 (has links)
Orientador: Edwil Aparecida de Lucca Gattás / Banca: Eleonora Cano Carmona / Banca: Rubens Monti / Resumo: A levedura Pichia pastoris vem sendo largamente utilizada como um eficiente sistema de expressão para a produção de proteínas heterólogas, pois é um sistema seguro, fácil e mais barato que sistemas de expressão de outros eucariotos. Neste trabalho, a enzima de interesse é a glicerol quinase (GK), que cataliza a transferência do fosfato terminal do ATP para o glicerol originando glicerol-3-fosfato e ADP. Esta reação pode ser utilizada na determinação da concentração de glicerol, subproduto da fermentação alcoólica. A leitura do consumo de glicerol é realizada pela determinação espectrofotométrica do NADH gerado na reação de oxido-redução catalizada pela enzima glicerol-3-fosfato desidrogenase. Este estudo de indução foi realizado em diferentes condições de crescimento da levedura Pichia pastoris. Os resultados mostraram a seleção do melhor clone da levedura Pichia pastoris para a expressão extracelular da enzima glicerol quinase, e a determinação das melhores condições do meio de cultura para a produção da enzima de interesse foram: concentração do meio de cultura BMMY (20 vezes), densidade inicial de célula (0,1 mg/mL), concentração de metanol na fase de indução (1%), natureza do tampão (fosfato de potássio), pH (6,0), suplementação de glicerol no meio BMMY (1%), peptona (marca Difco), sem adição de sulfato de amônio, caseína e glicina, uso do meio BMMY e liofilização do mesmo. Estudos de parâmetros cinéticos foram realizados e a atividade máxima da GK foi obtida em pH 9,8, a 50ºC e 2,5 μM de substrato, por metodologia clássica, além da presença de sulfato de magnésio e diluição da enzima de 30 vezes. A enzima apresentou alta estabilidade térmica ― a atividade foi completamente... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The yeast Pichia pastoris has been widely used as an efficient expression system for production of heterologous proteins because it is a safe, easy and cheaper than expression systems in other eukaryotes.In this studie, the enzyme of interest is glycerol kinase (GK), which catalizes the transfer of terminal phosphate from ATP to glycerol resulting glycerol-3-phosphate and ADP. This reaction can be used in determining the concentration of glycerol, a byproduct of fermentation. The reading of the consumption of glycerol is carried out by spectrophotometric determination of NADH generated in the redox reaction catalyzed by the enzyme glycerol-3-phosphate dehydrogenase. This study of induction was performed in different conditions of growth of the yeast Pichia pastoris. The results show that selecting the best clone of the yeast Pichia pastoris for the expression of extracellular enzyme glycerol kinase, and determining the best conditions of the culture medium for producing the enzyme of interest were: concentration of the culture medium BMMY (20 times), initial cell density (0.1 mg/mL), methanol concentration in the induction phase (1%), nature of buffer (potassium phosphate), pH (6.0), glycerol supplementation in BMMY medium (1%), peptone (Difco), without addition of ammonium sulfate, casein and glycine in BMMY and lyophilized medium. Studies of kinetic parameters were conducted and the GK maximum activity was obtained at pH 9.8 at 50°C and 2.5 μM substrate by conventional method, besides the presence of magnesium sulfate and diluting the enzyme 30 times. The enzyme showed high thermal stability - the activity was fully maintained up to 50°C for one hour - and at pH 7.0 for 7 days and kept under refrigeration, freeze-dried extract showed a decrease in enzymatic activity. Calculated by... (Complete abstract click electronic access below) / Mestre
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Hidrogenólise do glicerol a dióis catalisada por metais de transição suportados em argilas pilarizadas / Hydrogenolysis of glycerol to diols catalyzed by transition metals supported on pillared claysZanin, Cristiane Imenes de Campos Bueno 16 August 2018 (has links)
Orientadores: Elizabete Jordão, Wagner Alves Carvalho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-16T19:26:07Z (GMT). No. of bitstreams: 1
Zanin_CristianeImenesdeCamposBueno_M.pdf: 1177792 bytes, checksum: 1d486d6f780a5b8b17b181686be89bd5 (MD5)
Previous issue date: 2010 / Resumo: O aproveitamento do glicerol tem se tornado assunto de grande importância, uma vez que ele é um subproduto da síntese do biodiesel. Além de fatores econômicos e políticos, a partir da década de 1990, devido a um aumento da conscientização acerca dos problemas ambientais causados pela queima de combustíveis fósseis, o biodiesel tem sido apontado como alternativa, fazendo com que a produção de glicerol aumente cada vez mais, diminuindo assim o seu preço. Contudo, é de grande importância sua transformação em produtos com maior valor agregado como os dióis, com interesse voltado para a indústria petroquímica. Com a finalidade de se expandir a produção de biodiesel, torna-se necessário o desenvolvimento de uma ?nova química do glicerol?, sendo a hidrogenólise para diálcoois bastante promissora. O presente trabalho tem o objetivo de estudar a influência da quantidade de catalisador, pressão de H2 e da temperatura na velocidade inicial das reações, bem como na seletividade e no total de conversão do substrato, a partir de catalisadores de Pt, Pd e Ru suportados em argila pilarizada (A?-PilC). Os catalisadores foram preparados através de impregnação em suspensões aquosas, a partir dos precursores Pt (NH3)4Cl2.0,68H2O, PdCl2 e RuCl3.1,37H2O, respectivamente, de modo a obter um catalisador com teor nominal de 2% em peso. Os catalisadores preparados foram caracterizados por meio das técnicas: área superficial específica (B.E.T.), redução à temperatura programada (TPR), difração de raios X (DRX), espectroscopia na região do infravermelho (FTIR) de piridina adsorvida e dessorção de piridina a temperatura programada. O desempenho dos catalisadores foi avaliado na reação de hidrogenólise do glicerol em fase líquida, empregando-se um reator Parr de alta pressão. Os resultados obtidos indicam que o uso de catalisadores bifuncionais metal-ácido é uma forma de tornar a hidrogenólise mais efetiva, uma vez que favorecem as reações de desidratação e hidrogenação para a produção de 1,2-propanodiol / Abstract: The use of glycerol has become a subject of great importance, since it is a byproduct of the synthesis of biodiesel. Besides economic and political factors, from the 1990s, due to environmental problems caused by burning fossil fuels, biodiesel has been become an alternative, making the production of glycerol increases more, thereby lowering its price. However, it is of great important its transformation into products with higher added value such as diols, with interest focused on the petrochemical industry. In order to expand the production of biodiesel, it becomes necessary to develop a "new chemistry of glycerol?, and the hydrogenolysis to dialcohols is promising. The present work aims to study the influence of substrate concentration, amount of catalyst, H2 pressure and temperature on initial velocity of reactions, as well as selectivity and total conversion of substrate, using catalysts based on Pt, Pd and Ru supported on pillared clay (A?-PILC). The catalysts were prepared by impregnation with aqueous suspensions, from the precursor Pt (NH3)4Cl2.0, 68H2O, PdCl2 and RuCl3.1, 37H2O, respectively, to obtain a catalyst with nominal content of 2% ww. The catalysts were characterized by the methods: specific surface area (B.E.T.), temperature programmed reduction (TPR), X-ray diffraction (DRX), infrared spectroscopy (FTIR) of adsorbed pyridine and the pyridine desorption temperature. The performance of the catalysts was evaluated in the reaction of hydrogenolysis of glycerol in the liquid phase, using a high pressure Parr reactor. The results indicate that the use of bifunctional metal-acid catalysts is a way to make the hydrogenolysis more effective, because it favors the dehydration and hydrogenation reactions to produce 1,2-propanediol / Mestrado / Sistemas de Processos Quimicos e Informatica / Mestre em Engenharia Química
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