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1.
Jale F. Akyurtlu Ates Akyurtlu Charles E. Hamrin JR 《Chemical Engineering Communications》1988,66(1):169-187
A theoretical investigation of a catalytic porous-wall reactor in which gaseous and liquid reactants approach each other from opposite sides of the catalyst is undertaken. Equations for the annular liquid-channel are coupled with those for the catalytic wall and solved numerically and analytically using a simplified model. For the model reaction under study, the main design and operation parameters which affect reactor performance are the Thiele modulus, Peclet number, width of the liquid channel and the inlet concentration of the reactant in the liquid phase.
The effect of reactor configuration is peculiar to the cylindrical geometry because the thickness and relative location of the catalytic wall as well as the selection of the liquid and gas channels can influence the reactor performance. Thin-walled catalyst tubes have larger effectiveness factors and as the tube radius approaches that of the reactor, conversion in the reactor increases especially when the liquid is saturated with the gaseous reactant. Concentration of the liquid reactant in the feed has a significant effect if the reactant is depleted at some point inside the catalyst wall. Since the reaction zone width can be adjusted by changing the feed composition, this might have important implications with respect to selectivity. 相似文献
The effect of reactor configuration is peculiar to the cylindrical geometry because the thickness and relative location of the catalytic wall as well as the selection of the liquid and gas channels can influence the reactor performance. Thin-walled catalyst tubes have larger effectiveness factors and as the tube radius approaches that of the reactor, conversion in the reactor increases especially when the liquid is saturated with the gaseous reactant. Concentration of the liquid reactant in the feed has a significant effect if the reactant is depleted at some point inside the catalyst wall. Since the reaction zone width can be adjusted by changing the feed composition, this might have important implications with respect to selectivity. 相似文献
2.
Jale Acar V. G?kmen Esma Elden Taydas 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1998,207(4):328-331
The effects of different treatments on the patulin content of apple juice during the production of industrial apple juice
concentrate were investigated. Conventional clarification using a rotary vacuum precoat filter was found to be more effective
than using ultrafiltration for the removal of patulin from apple juice. The average losses of patulin were 39% and 25% for
conventional clarification and filtration, and ultrafiltration, respectively. Washing and handling appeared to be the most
critical steps in removing patulin from apples since up to 54% could be removed using high-pressure water spraying.
Received: 22 January 1998 / Revised version: 21 April 1998 相似文献
3.
In this study, pyrolysis mass spectrometry has been applied for the investigation of thermal characteristics of ‐doped polythiophene (PTh) films. Thermal degradation of PTh showed behaviour identical with ‐doped polythiophene (BF4‐PTh), indicating that the effects of the dopants in question on the thermal characteristics of the PTh are not significant. Besides the oligomer peaks (up to hexamer), peaks indicating decomposition of the thiophene ring have also been detected as in the case of BF4‐PTh. However, the data also indicated that the oxidation of the dopant was much more effective, yielding mainly POF3, H3PO4 compounds even for the freshly prepared samples. Upon ageing, the yield of these products increased and exposure to air for more than 50 days also caused degradation of the PTh chains. Furthermore, substitution of the thiophene (Th) ring by fluorine has been recorded and was associated with reactions of Th with the reactive oxidation products of the dopant. Analyses of the de‐doped samples showed that although de‐doping was effective to a certain extent, inward diffusion of the counter ion (C4H9)4N+ has also occurred. This diffusion was more efficient than that was observed for BF4‐PTh samples. Copyright © 2004 Society of Chemical Industry 相似文献
4.
Jale Müslehiddinolu Paul Lobben Simon Leung Lori Spangler San Kiang 《Catalysis Today》2007,123(1-4):164-170
Hydrogenolysis of a carbobenzyloxy group (CBz) was studied utilizing molecular hydrogen in the presence of carbon-supported palladium catalyst. It was demonstrated that the kinetics of the reaction are greatly influenced by the presence of the CO2 by-product. It was found out that the presence of CO2 determines whether the reaction is first or zero order since it causes deactivation of the catalyst via inhibition. The effect of potassium carbonate (K2CO3) and triethylamine (TEA) as additives was investigated. A considerable solvent effect was also observed that may be explained by the variation of dispersion of the catalyst from one solvent to another. 相似文献
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6.
The effects of dough formula and baking conditions on the formations of acrylamide and hydroxymethylfurfural (HMF) were studied in a cookie model system. Increasing the sugar concentration in the dough formula increased acrylamide formation during baking at 205 °C for 11 min. The effect of sugar on acrylamide formation was more pronounced for glucose than for sucrose, expectedly. Addition of citric acid into dough formula comprising sucrose increased the susceptibility of acrylamide formation, while it decreased acrylamide formation in the dough formula comprising glucose. Decreasing the pH of dough formula increased the tendency to surface browning and the formation of hydroxymethylfurfural in cookies during baking. The results suggest that a cookie with acceptable texture and colour, but having less than 150 ng/g of acrylamide, can be manufactured by lowering the baking temperature and avoiding reducing sugars in the recipe. 相似文献
7.
In this study, apples inoculated with pure cultures of Rhizopus stolonifer, Penicillium expansum and Lactobacillus plantarum were utilised as the raw material to produce apple juice concentrate. The effects of microorganisms and various processing
treatments on the fumaric acid, lactic acid and patulin contents of apple juice were investigated. R. stolonifer was found to be the most responsible causative agent of fumaric acid and lactic acid. L. plantarum also produced certain amounts of lactic acid, but not as much as R. stolonifer. L. plantarum caused a significant decrease in L-malic acid content indicating the occurrence of malolactic fermentation. During this complicated
biochemical pathway, a small amount of fumaric acid was also formed by L. plantarum. P. expansum produced only patulin, but did not affect the fumaric acid and lactic acid contents. Fumaric acid contents of the samples
decreased throughout the processing steps excepting evaporation. The fumaric acid contents of the samples increased just after
evaporation depending on the heat applied. The patulin and lactic acid contents of the samples also showed a decreasing trend
throughout processing. However, L. plantarum caused a significant increase in lactic acid content just after depectinization depending on whether the appropriate time-temperature
conditions for incubation were available during depectinization.
Received: 3 November 1998 / Revised version: 4 January 1999 相似文献
8.
Soydan?OzcanEmail author Jale?Tezcan Bijay?Gurung Peter?Filip 《Journal of Materials Science》2011,46(1):38-46
This paper investigates the effect of heat treatment temperature on the interfacial shear strength (IFSS) of carbon/carbon
composites reinforced with polyacrylonitrile-based fibers. A series of single fiber push-out tests were performed on specimens
heat treated at 1800, 2100, and 2400 °C, using a nanoindenter with a flat ended conical tip. The microstructure was characterized
using polarized light and transmission electron microscopy and the debonded fiber/matrix interface was examined using scanning
electron microscopy. Wavelet analysis of the load–displacement data was used as an additional tool to investigate the initiation
and progression of debonding. Compared to 1800 °C, heat treatment at 2400 °C was associated with a decrease in IFSS, from
12 to 7 MPa. Transmission electron microscopy study showed that the microstructure of the fiber/matrix interphase remained
amorphous even with heat treatment at 2400 °C. The decrease in the IFSS can be partly attributed to the reorganization of
the graphene sheets in the matrix in the vicinity of fiber/matrix interphase. The thermal expansion mismatch between fiber
and pyrocarbon matrix is another possible reason for the observed decrease in the IFSS. 相似文献
9.
Dr. Andreas Gollner Dr. Harald Weinstabl Dr. Julian E. Fuchs Dr. Dorothea Rudolph Dr. Geraldine Garavel Karin S. Hofbauer Jale Karolyi-Oezguer Gerhard Gmaschitz Wolfgang Hela Dr. Nina Kerres Elisabeth Grondal Patrick Werni Dr. Juergen Ramharter Dr. Joachim Broeker Dr. Darryl B. McConnell 《ChemMedChem》2019,14(1):88-93
Mouse double minute 2 (MDM2) is a main and direct inhibitor of the crucial tumor suppressor p53. Reports from initial clinical trials showed that blocking this interaction with a small-molecule inhibitor can have great value in the treatment of cancer for patients with p53 wild-type tumors; however, it also revealed dose-limiting hematological toxicities and drug-induced resistance as main issues. To overcome the former, an inhibitor with superior potency and pharmacokinetic properties to ultimately achieve full efficacy with less-frequent dosing schedules is required. Toward this aim, we optimized our recently reported spiro-oxindole inhibitors by focusing on the crucial interaction with the amino acid side chain of His96MDM2. The designed molecules required the targeted synthesis of structurally complex spiro[indole-3,2′-pyrrolo[2,3-c]pyrrole]-2,4′-diones for which we developed an unprecedented intramolecular azomethine ylide cycloaddition and investigated the results by computational methods. One of the new compounds showed superior cellular potency over previously reported BI-0252. This finding is a significant step toward an inhibitor suitable to potentially mitigate hematological on-target adverse effects. 相似文献
10.
Chandrashekar P. Kelkar Jale F. Akyurtlu Ates Akyurtlu Charles E. Hamrin Jr. 《Chemical Engineering Communications》1992,117(1):101-109
A novel annular catalytic three-phase reactor is theoretically investigated for a second order hydrogenation reaction. The results indicate that the ratio of the gaseous reactant to the liquid reactant within the reaction zone of the annular reactor can be adjusted by changing the reactor dimensions and the concentration of the gaseous reactant in the feed. As a consequence, the annular reactor may have a significant advantage over the trickle-bed reactor with respect to the selectivities that may be achieved in the reactor. 相似文献