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71.
EPR and conductivity measurements on the “one-dimensional” semiconductor Magnus' Green Salt doped with Fe or Cu impurities are described. It is found that the introduction of these impurities causes significantly higher localization of the previously identified dz2 holes. 相似文献
72.
Raymond JW Jalaie M Bradley MP 《Journal of chemical information and computer sciences》2004,44(2):601-609
This paper introduces a new consensus scoring approach for merging the results of different virtual screening methods based on conditional probabilities. The technique is experimentally evaluated using several ligand-based virtual screening methods and compared to two variations of the established Sum-rank fusion method where it performs as well or better than the Sum-rank methods. Our experiments confirm that consensus scoring increases the number of active compounds retrieved with respect to the best individual methods on average. 相似文献
73.
Triton X-100-substituted Sepharose 4B (Sepharose-TX) was used for adsorptive immobilization of intestinal brush border membrane
using lactose-phlorizin hydrolase as a representative membrane enzyme. Limited heating of membrane preparations was found
to enhance binding. This enhancement is concluded to be owing to a greater availability of the hydrophobic sites, as also
confirmed by the 1-anilino-8-naphthalene sulfonate fluorescence studies, for interaction with Triton X-100 moieties on the
support. The immobilized preparations obtained by this procedure were found useful in hydrolysis of lactose, involving lactose-phlorizin
hydrolase, in continuous operations. It is suggested that the approach may be of general utility for immobilization of biologic
membranes by interaction of their extramembrane structures using supports with appropriate hydrophobic groups. 相似文献
74.
Ali Jebali Seyedhossein Hekmatimoghaddam Aliasghar Behzadi Iraj Rezapor Bahador Haji Mohammadi Tahereh Jasemizad Seyed Ali Yasini Morteza Javadzadeh Asiye Amiri Mansoure Soltani Zeynab Rezaei Najme Sedighi Mina Seyfi Mohammad Rezaei Mehran Sayadi 《Cellulose (London, England)》2013,20(6):2897-2907
In this study, cellulose nanoparticles were prepared by acid hydrolysis, separately conjugated with allicin and lysozyme by a carbodiimide cross-linker, and characterized by scanning electron microscopy, dynamic light scattering, and Fourier transform infrared spectroscopy. Then, their antimicrobial properties were evaluated by the microdilution method and compared with allicin, lysozyme, and nanocellulose alone. The results showed that nanocellulose had few antimicrobial activities, but allicin-conjugated nanocellulose (ACNC) and lysozyme-conjugated nanocellulose (LCNC) had good antifungal and antibacterial effects against standard strains of Candida albicans, Aspergillus niger, Staphylococcus aureus, and Escherichia coli. Noticeably, although allicin and lysozyme had different minimum inhibitory concentrations (MICs) against all strains, the same quantity of MIC50 and MIC90 was observed for both ACNC and LCNC. The authors suggest that both ACNC and LCNC can be used in industries as an antimicrobial agent in food packaging, inside foodstuffs, and in textile materials. 相似文献
75.
Mehran Asad Ayoubi Kaizheng Zhu Bo Nyström Ulf Olsson Kristoffer Almdal Alexei R. Khokhlov Lennart Piculell 《Journal of Polymer Science.Polymer Physics》2013,51(23):1657-1671
Samples of compositionally (highly) asymmetric diblock copolymers and, also, mixtures of diblock and triblock copolymers (the latter obtained as end‐coupling products of two diblock molecules of the mixture), composed of (a) monodisperse majority block(s) of poly(styrene) (PS) and a polydisperse minority block of poly(methacrylic acid) (PMAA), microphase separate into spherical PMAA microdomains, either in disordered liquid‐like state or body‐centered‐cubic (BCC) arrangement, at various annealing temperatures T, in the strong segregation regime SSR. We found that (i) the microphase separated state is favored over an anticipated molecularly homogenous state, (ii) the spherical microdomain morphology (with BCC symmetry) is favored over an anticipated hexagonally packed cylindrical morphology, (iii) the extent of the dissolution of short PMAA blocks in the PS material can be quantified, (iv) the spherical microdomains are dilated, and (v) despite molecular‐weight (and architectural) polydispersity, well‐ordered BCC structures can be obtained. © 2013 Wiley Periodicals, Inc. J. Polym. Sci. Part B: Polym. Phys. 2013 , 51, 1657–1671 相似文献
76.
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78.
Nanocrystalline MgO with a relatively high surface area and mesoporous structure was synthesized by a surfactant assisted precipitation method for use as the support of nickel catalysts for steam reforming of methane. The samples were characterized by X‐ray diffraction, N2 adsorption, temperature‐programmed reduction, temperature‐programmed oxidation, scanning electron microscopy, and transmission electron microscopy. The catalysts showed high catalytic activity and good stability in the steam reforming of methane. Increasing the nickel loading up to 10 wt% gave increased activity. Catalysts with higher nickel loadings showed more deposited carbon after reaction. The excellent anti‐coking performance of the catalysts was attributed to the formation of a nickel‐magnesia solid solution, basicity of the support surface, and nickel‐support interaction. 相似文献
79.
Seyed Mohammad Shoaei Hossein Aghaei Majid Monajjemi Mehran Aghaei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):652-660
The mechanism of electrochemical oxidation of catechol and some of its derivatives have been studied in the presence of triethyl phosphite as a nucleophile in aqueous solution. Voltammetric studies indicate that the quinones derived from catechol, and its derivatives, participate in Michael addition reaction with triethyl phosphite. The reaction mechanism consists of electron transfer followed by a chemical reaction which is named as an EC mechanism. The homogeneous rate constants (kobs) were estimated by comparing the experimental cyclic voltammograms with the digitally simulated voltammograms based on EC mechanism. Also the effects of nucleophile concentration and substituted group of catechols on voltammetric behavior and the rate constants of chemical reactions were examined. 相似文献
80.
Dr. Farah Kawtharani Dr. Svetlana Mintova Dr. Richard Retoux Prof. Mehran Mostafavi Dr. Guy Buntinx Dr. Vincent De Waele 《Chemphyschem》2020,21(24):2634-2643
Silver cations were introduced in nanosized BEA-type zeolite containing organic template by ion-exchange followed by chemical reduction towards preparation of photoactive materials (Ag0-BEA). The stabilization of highly dispersed Ag0 nanoparticles with a size of 1–2 nm in the BEA zeolite was revealed. The transient optical response of the Ag-BEA samples upon photoexcitation at 400 nm was studied by femtosecond absorption. The photodynamic of the hot electrons was found to depend on the sample preparation. The lifetime of the hot electrons in the Ag−BEA samples containing small Ag nanoparticles (1–2 nm) is significantly shortened in comparison to bear Ag nanoparticles with a size of 10 nm. While for the larger Ag nanoparticles, the energy absorbed in the conduction band is decaying by electron-phonon coupling into the metal lattice, the high surface-to-volume ratio of the small Ag nanoparticles favors the dissipation of the energy of the hot electrons from the metal nanoparticles (Ag0) towards the zeolitic micro-environment. This finding is encouraging for further applications of Ag-containing zeolites in photocatalysis and plasmonic chemistry. 相似文献