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The structural, electronic and magnetic properties of small gallium clusters doped with Cobalt have been studied using spin-polarised density functional theory. The binding energy per atom, second-order differences of total energies and fragmentation energies of equilibrium geometries of the host Gan+1 and doped GanCo (n = 1–12) clusters are computed. Doped clusters are found to be more stable than pure Ga clusters; Ga3Co, Ga5Co and Ga8Co clusters are exceptionally stable. Doping with Co changes the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO–LUMO) gap, and also affects the magnetic moments of clusters. 相似文献
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Munish Puri Shivani Gupta Parveen Pahuja Aneet Kaur J. R. Kanwar J. F. Kennedy 《Applied biochemistry and biotechnology》2010,160(1):98-108
β-D-galactosidase (EC 3.2.1.23) from Kluyveromyces marxianus YW-1, an isolate from whey, has been studied in terms of cell disruption to liberate the useful enzyme. The enzyme produced
in a bioreactor on a wheat bran medium has been successfully immobilized with a view to developing a commercially usable technology
for lactose hydrolysis in the food industry. Three chemical and three physical methods of cell disruption were tested and
a method of grinding with river sand was found to give highest enzyme activity (720 U). The enzyme was covalently immobilized
on gelatin. Immobilized enzyme had optimum pH and temperature of 7.0 and 40 °C, respectively and was found to give 49% hydrolysis
of lactose in milk after 4 h of incubation. The immobilized enzyme was used for eight hydrolysis batches without appreciable
loss in activity. The retention of high catalytic activity compared with the losses experienced with several previously reported
immobilized versions of the enzyme is significant. The method of immobilization is simple, effective, and can be used for
the immobilization of other enzymes. 相似文献
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The oxidation of α-benzoyl-o-hydroxyacetophenones (3a-d) using iodobenzene diacetate in methanolic potassium hydroxide provides a new direct method for the synthesis of 2-benzoylcoumaran-3-ones (4a-c) in good yields. The formation of 4a-d is explained by neighb uring group participation. 相似文献
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Glutamine and gamma-aminobutyric acid (GABA), formed from glutamic acid in crude tissue extracts by glutamine synthetase and glutamic acid decarboxylase respectively, were separated by derivatization with dansyl chloride followed by reversed-phase high-performance liquid chromatography on the Altex Ultrasphere ODS-5 column. The mobile phase was a gradient of 100 mM potassium dihydrogen phosphate (pH 2.1) with 0-40% acetonitrile. The amounts of glutamine and GABA formed from glutamic acid were determined under different reaction conditions. 相似文献
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This paper discusses experimental isotherms and isobars of polyoxymethylene, polyethyleneoxide, and poly(tetrahydrofuran) that have been analyzed in terms of our theory of anharmonic polymer crystals. The trends shown by various characteristic parameters for these polyethers are interpreted in terms of their chemical structure. 相似文献
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Hypervalent iodine oxidation of several flavanones (1a-1f) using (hydroxy(tosyloxy)iodo] benzene in methanol offers a new method for the synthesis of flavones (2a-2f). 相似文献
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Abhishek Pahuja Manoj Singh Parihar V. Dinesh Kumar 《Optical and Quantum Electronics》2018,50(11):401
A theoretical study on nanoantenna and its application in enhancing the performance of the thin film solar cell (TFSC) is presented. In this work, a novel design of nanoantenna i.e. Euler spiral nanoantenna (ESNA) is introduced, which has evolved after bending the conventional dipole nanoantenna in the manner of Euler spiral. The bending is performed up to an optimum length so that the antenna can equally respond to the two orthogonally polarized waves. Then the proposed nanoantenna in turnstile manner is examined for the intended application of enhancing the absorption in TFSCs. The antenna is placed on the absorber layer (Si amorphous) of the TFSC with a coating of Zinc Oxide. The simulation results show that the proposed ESNA can significantly increase the absorption in the absorber layer of the TFSC. The performance in terms of absorption and quantum efficiency of the solar cell incorporated with ESNA has been studied. ESNA confines the electric field in a larger area which results in absorption increase. The simulation results show that proposed ESNA can enhance the absorption up to 97.6% in the absorber layer and the photocurrent is enhanced by a factor of 1.39. To the best of our knowledge, this is the first study on Euler spiral nanoantenna and so as in its application with solar cells. 相似文献
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