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排序方式: 共有103条查询结果,搜索用时 15 毫秒
81.
Candida parapsilosis ATCC 7330 was found to be an efficient biocatalyst for the deracemisation of aryl α-hydroxy esters (65–85% yield and 90–99% ee). A variety of aryl and aryl substituted α-hydroxy esters were synthesized to reflect steric and electronic effects on biocatalytic deracemisation. The mechanism of this biocatalytic deracemisation was found to be stereoinversion. 相似文献
82.
83.
S Chanda Sarmishtha Bhattacharyya Tumpa Bhattacharjee SS Ghugre Swapan Kumar Basu S Muralithar RP Singh B Mukherjee RK Bhowmik SN Ray 《Pramana》2001,57(1):175-179
The high spin states in N=80 139Pr have been investigated by in-beam γ-spectroscopic techniques following the reaction 130Te (14N, 5n) reaction at E=75 MeV, using a gamma detector array, consisting of seven 23% compton-suppressed high purity germanium detectors and a multiplicity
ball of fourteen bismuth germanate elements. Based on γ-γ coincidence data, the level scheme of 139Pr has been considerably extended up to 7.2 MeV excitation. Tentative spin-parity assignments are done for the newly proposed
levels on the basis of the DCO ratios corresponding to strong gates and the available information from the earlier light ion
experiments. 相似文献
84.
85.
Chinnadurai T. Prabaharan N. Raj N. Mohan Pandian M. Karthigai 《Journal of Thermal Analysis and Calorimetry》2018,132(3):1813-1824
Journal of Thermal Analysis and Calorimetry - Automobile industries are focusing toward the reduction in the weight of vehicle that leading to cost reduction and improving the fuel efficiency.... 相似文献
86.
Himalay Basumatary Mithun Palit J. Arout Chelvane S. Pandian M. Manivel Raja V. Chandrasekaran 《Journal of magnetism and magnetic materials》2010,322(18):2769-2772
Alloys of Fe77Ga23Bx (x=0, 0.025, 0.050, 0.075 and 0.1) were heat treated at 1000 °C/10 h and characterized for microstructural features and magnetostriction. The study indicates that the parent alloy consists of three phases viz. A2 as the major phase and L12 and DO3 as minor phases. However, the volume fraction of L12 and DO3 decreases with B addition and as a result magnetostriction improves. The decrease in volume fraction of these phases is attributed to B-segregation to the grain boundary, which seems to prevent the formation of these phases. The alloy with x=0.1, however, exhibits an additional Fe2B phase and consequently its presence leads to the re-emergence of the DO3 phase, affecting the magnetostriction. 相似文献
87.
The electron paramagnetic resonance (EPR) spectra of sodic plagioclase from dykes of granitic pegmatite occurring in the Kadavur area, Tamil Nadu, India, were examined at room temperature to identify paramagnetic impurities in a “low plagioclase” using EPR and optical techniques. The EPR spectra showed the presence of Fe(III) and Mn(II) impurities. After heating the plagioclase samples for various durations at 600 °C, it has been observed that the concentration of Mn(II) remained as such in one sample but completely disappeared in another sample, while there was no change in Fe(III) ion concentration after the heat treatment in either sample. Optical absorption spectra also showed Fe(II) and Fe(III) in addition to Ti(III) impurities in sodic plagioclase before heating, while after heating the relative concentration of Fe(II) and Fe(III) changed, accompanied by the disappearance of Ti(III). 相似文献
88.
Baburaj Baskar N. Ganesh Pandian Kuttikode Priya Anju Chadha 《Tetrahedron: Asymmetry》2004,15(24):3961-3966
Enantioselective bioreduction of alkyl 2-oxo-4-arylbutanoates and 2-oxo-4-arylbut-3-enoates mediated by Candida parapsilosis ATCC 7330 resulted in the formation of the corresponding (S)-2-hydroxy compounds in high enantiomeric excesses (93–99%) and good isolated yields (58–71%). The absolute configuration of enantiomerically pure ethyl 2-hydroxy-4-(p-methylphenyl)but-3-enoate obtained by the reduction of the corresponding keto ester was assigned by 1H NMR using Mosher’s method. 相似文献
89.
One pot synthesis of polymer protected gold nanoparticles and nanoprisms in glycerol 总被引:1,自引:0,他引:1
A. Nirmala Grace K. Pandian 《Colloids and surfaces. A, Physicochemical and engineering aspects》2006,290(1-3):138-142
Uniform and stable polymer protected spherical gold nanoparticles were synthesized using glycerol as reducing agent. Further it was observed that the morphology of the particles varied from spherical to triangular prismatic gold nanoparticles when the reaction was changed from normal mode of reflux condition to microwave mode (MW) of heating. Further a brief mechanism relating the formation of prisms with the orientation of polymer and nucleation period has been discussed. Formation of triangular prismatic and spherical gold nanoparticles were characterised using UV–vis spectroscopy, transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. 相似文献
90.
Kaliyaperumal Ashokkumar Arjun Pandian Muthusamy Murugan M.K. Dhanya Thiravidamani Sathyan Paramasivam Sivakumar 《Natural product research》2020,34(9):1306-1310
AbstractThe objective of this study was to examine the bioactive flavonoids and carotenoids concentration in fifteen south Indian spice and two tree nut species using high performance liquid chromatography (HPLC). Among four flavonoids, catechin concentration was the highest in all spices and nuts and ranged between 97.1 and 1745.4 µg g?1. Quercetin concentration was the greatest in cinnamon, followed by garlic and cumin and ranged from 0.4 to 65 µg g?1 in other spices and nuts. Lutein concentration ranged from 0.1 to 102.8 µg g?1. Of the spices and nuts studied, β-carotene concentration was highest in coriander leaves (74.7 µg g?1), followed by red pepper (12.5 µg g?1) and curry leaves (8.5 µg g?1). This research shows that consumption of south Indian spices and nuts could substantially benefit consumers living in regions experiencing Vitamin A and other micronutrient deficiencies. 相似文献