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1	Investigation of the Feasibility of Manufacturing Solid Oxide Fuel Cell Graded Electrolytes by Suspension Plasma Spraying Arevalo-Quintero, Olga Lucia 31 August 2012 (has links) Solid oxide fuel cell compositionally graded electrolytes could offer the advantage of improving electrical performance and efficiency compared to single-layered or bi-layered yttria stabilized zirconia and samaria doped ceria electrolytes and improving mechanical performance by reducing thermal expansion mismatch stresses compared to bi-layered electrolytes with sharp interfaces. Manufacturing of these graded structures is difficult if implementing conventional wet ceramic techniques. Suspension plasma spraying is an emerging technology that has the potential to rapidly produce thin, dense ceramic layers with no requirement for post deposition heat treatments. However, SPS requires a careful examination of the stability of the feedstock suspensions in order to produce high quality coatings. Optimum suspension formulations with excellent particle dispersion were designed based on rheological and electrostatic stability measurements. These optimized suspensions were used as feedstocks for the fabrication of suspension plasma sprayed compositionally graded YSZ/SDC layers. The feasibility of fabricating graded electrolyte structures was thus demonstrated. Graded YSZ/SDC electrolyte Electrostatic stability Isoelectric point Suspension plasma spraying 0548
2	Investigation of the Feasibility of Manufacturing Solid Oxide Fuel Cell Graded Electrolytes by Suspension Plasma Spraying Arevalo-Quintero, Olga Lucia 31 August 2012 (has links) Solid oxide fuel cell compositionally graded electrolytes could offer the advantage of improving electrical performance and efficiency compared to single-layered or bi-layered yttria stabilized zirconia and samaria doped ceria electrolytes and improving mechanical performance by reducing thermal expansion mismatch stresses compared to bi-layered electrolytes with sharp interfaces. Manufacturing of these graded structures is difficult if implementing conventional wet ceramic techniques. Suspension plasma spraying is an emerging technology that has the potential to rapidly produce thin, dense ceramic layers with no requirement for post deposition heat treatments. However, SPS requires a careful examination of the stability of the feedstock suspensions in order to produce high quality coatings. Optimum suspension formulations with excellent particle dispersion were designed based on rheological and electrostatic stability measurements. These optimized suspensions were used as feedstocks for the fabrication of suspension plasma sprayed compositionally graded YSZ/SDC layers. The feasibility of fabricating graded electrolyte structures was thus demonstrated. Graded YSZ/SDC electrolyte Electrostatic stability Isoelectric point Suspension plasma spraying 0548
3	Electrostaticanalisys the Ras active site Khan, Abdul Kareem 05 March 2009 (has links) La preorganització electrostàtica del centre actiu s'ha postulat com el mecanisme genèric de l'acció dels enzims. Així, alguns residus "estratègics" es disposarien per catalitzar reaccions interaccionant en una forma més forta amb l'estat de transició, baixant d'aquesta manera el valor de l'energia dactivació g cat. S'ha proposat que aquesta preorientació electrostática s'hauria de poder mostrar analitzant l'estabilitat electrostàtica de residus individuals en el centre actiu.Ras es una proteïna essencial de senyalització i actúa com un interruptor cel.lular. Les característiques estructurals de Ras en el seu estat actiu (ON) són diferents de les que té a l'estat inactiu (OFF). En aquesta tesi es duu a terme una anàlisi exhaustiva de l'estabilitat dels residus del centre actiu deRas en l'estat actiu i inactiu. / The electrostatic preorganization of the active site has been put forward as the general framework of action of enzymes. Thus, enzymes would position "strategic" residues in such a way to be prepared to catalyze reactions byinteracting in a stronger way with the transition state, in this way decreasing the activation energy g cat for the catalytic process. It has been proposed thatsuch electrostatic preorientation should be shown by analyzing the electrostatic stability of individual residues in the active site.Ras protein is an essential signaling molecule and functions as a switch in thecell. The structural features of the Ras protein in its active state (ON state) are different than those in its inactive state (OFF state). In this thesis, an exhaustive analysis of the stability of residues in the active and inactive Ras active site is performed. dinàmica centre actiu relacions d'estructura activitat preorganització reorganització estat de transició estat actiu estabilitat electrostàtica interacción proteïna-proteïna test de ranks de Wilcoxon P-loop G1 motif HVR metastability RMSD substrate assisted catalysis sequence alignment beta sheet helix Z-test wilcoxon rank test protein-protein interactions electrostatic stability active state dynamics signal transduction electrostatic stabilization ras effectors guanine exchange factor GTPase-activating proteins quantum mechanics/molecular PDLD/S-LRA X-ray crystallography solvation energy free energy perturbation statistical analysis GTP hydrolysis guanosine diphosphate guanosine triphosphate computer simulation thermodynamics protein conformation electrostatics interruptor II interruptor I llaç P motiu G1 HVR (regions altament variables) metaestabilita RMSD catàlisi assistida pel substrat aliniament de seqüència fulla beta hèlix test Z transducció del senyal estabilització electrostàtica efectors de ras factor de bescamvi de guanina proteïnes activadores de l'activitat mecànica quàntica/mecànica PDLD/S-LRA cristalografia de raigs X energia de solvatació perturbació de l'energia lliure anàlisi estadística hidròlisi de GTP difosfat de guanosina trifosfat de guanosina simulació computacional termodinàmica conformació proteïca electrostàtica switch-I switch-II 537 576

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