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91.
Amit L. Sharma Manju Gerard Rahul Singhal B. D. Malhotra S. Annapoorni 《Applied biochemistry and biotechnology》2001,96(1-3):155-165
Poly(2-fluoroaniline) was prepared by both chemical and electrochemical polymerization in acidic medium. Characterization
of poly(2-fluoroaniline) was accomplished experimentally using ultraviolet-visible, Fourier transform infrared, differential
scanning calorimetry, thermal gravimetric analysis, and X-ray diffraction techniques, respectively. Scanning electron microscopy
studies revealed globular morphology of chemically synthesized poly(2-fluoroaniline). The cyclic voltammetric studies revealed
diffusion-controlled phenomenon in electrochemically synthesized poly(2-fluoroaniline). 相似文献
92.
93.
Manju Ghosh 《Tetrahedron》2007,63(47):11710-11715
A simple route for the synthesis of enantiopure substituted γ-butyrolactones involving a highly diastereoselective alkylation of an enantiomerically pure substituted latent succinate ester is described. This route provides entry into both enantiomers of 3,4-disubstituted butyrolactones from a single enantiomer, 2,3-di-O-cyclohexylidine-R-(+)-glyceraldehyde. The synthetic potential of this methodology has been demonstrated by a formal synthesis of both enantiomers of enterolactone. 相似文献
94.
Photogalvanic effects were studied in photogalvanic cells containing sodium lauryl sulphate as surfactant, EDTA as reductant
and azur-B as photosensitizer. The photopotential and photocurrent generated were 814#x00B7;0 mV and 255·0 μA respectively.
The observed conversion efficiency was 1·2% and the maximum power of cell was 207·57 μW. The storage capacity of the cell
was 26#x00B7;0 min in dark. The effect of different parameters on electrical output of the cell was observed. A mechanism
has been proposed here for the generation of photocurrent in photogalvanic cells 相似文献
95.
Bhanu Prakash Vibhav Katoch Asmita Shah Manju Sharma M. Manolata Devi Jiban J Panda Jadab Sharma Ashok Kumar Ganguli 《Photochemistry and photobiology》2020,96(6):1273-1282
The present study is focused on the integration of microreactors to synthesize visible light active nanophotocatalysts for inline photocatalytic degradation of organic dye and antibacterial activity. A wire-assisted and a rapid laser micromachining technique has been employed for the fabrication of polydimethylsiloxane (PDMS) and poly(methyl methacrylate) (PMMA)-based microreactors, respectively. By varying the design and chemical reagents involved, different sizes of visible light active Ag2S nanoparticles were prepared via a continuous microfluidics approach using fabricated microreactors. When polyvinylpyrrolidone (PVP) was utilized as the capping agent during the reaction, smaller particles of the size of ~ 15 nm were observed. The photocatalytic performance of these nanoparticles has been evaluated inline by employing the single-inlet planar microreactor as a function of flow rate and channel length. The photocatalyst durability test and a comparative photocatalytic efficiency study between the microreactor and the conventional beaker reactor have also been carried out. Under visible light, these nanoparticles exhibit a remarkable enhancement of ~ 94.5% in the inline microreactor-based photocatalytic degradation of methylene blue dye. The slower the flow rate and longer the channel length, gradual enhancement in the performance has been observed. Also, these nanoparticles express an antibacterial effect with very high efficacy even at very low (2 mg mL−1) concentration toward the inhibition of Escherichia Coli. 相似文献
96.
An efficient, waste-free protocol has been developed for the synthesis of amides directly from nonactivated carboxylic acids and amines without any tedious purification. Fatty acids were also converted into corresponding amides by reaction with nonactivated amines. The synthesized amides were cyclized to tetrahydroisoquinolines in good yields. 相似文献
97.
A transition metal–free process, promoted by sodium borohydride, has been developed for convenient and selective hydration of nitriles to corresponding amides. The present process converts the aromatic, aliphatic, and heteroaromatic nitriles with wide functional group tolerance. The regioselective hydration of one nitrile moiety in the presence of an other nitrile group makes high impact in the present protocol. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource: Full experimental and spectral details.] 相似文献
98.
Sanjay Kumar Manju Taxak Nagaiyar Krishnamurthy 《Journal of Thermal Analysis and Calorimetry》2013,112(1):51-57
V4Cr4Ti alloy is synthesized by aluminothermy process followed by electron beam refining. Hydrogen absorption characteristics of the alloy have been evaluated by measuring the pressure composition isotherm (PCIT) at 57 °C temperature. Two plateau pressures are observed in the PCIT curve. Substantial decrease in the hydrogen absorption capacity of the alloy as compared to vanadium has been recorded. Hydrogen absorption kinetics of the alloy was investigated in the temperature range of 200–500 °C. Three-dimensional diffusion appears to be the rate controlling step of the hydrogen absorption. The apparent activation energy was calculated as 0.16 eV/atom-hydrogen. 相似文献
99.
The objective of this study was to examine the protective effect of phytic acid (PA) in reducing oxidative stress in an animal model for human hereditary hemochromatosis (HH) fed high-fat diets. Sixty-four ß2 microglobulin knockout (β2m KO) mice were randomly assigned to three treatments by feeding: control (basal), atherogenic (AT), and polyunsaturated fatty acid (PUFA) diets. One-half of the mice in each treatment group were fed 2% (wt/wt) PA. The ß2m+/+ mice (wild type (WT)) were fed a basal diet. All seven groups were fed for 10 weeks with a 50-ppm iron-containing diet (AIN-93G). Free iron and lipids were measured in serum samples. Nonheme iron, thiobarbituric acid-reactive substances (TBARS), superoxide dismutase (SOD), and catalase concentrations were measured in the liver tissue. Nonheme iron concentration in ß2m KO mice (on the basal diet) was 20× higher (p < 0.0001) than in the WT mice. Compared to the WT mice, ß2m KO mice had a significantly higher concentration of free iron in the serum (p < 0.0001), six-fold higher hepatic TBARs (p < 0.0001), and 18% lower hepatic SOD level. When PA was added to the β2m KO basal diet, a reduction (26 to 50%) of iron concentration was seen in the liver and heart. The addition of PA also significantly reduced TBARs in all three dietary groups of the iron-overloaded group, but most effectively in the control group. An increase in SOD concentration was seen only in the PUFA group, but serum triacylglycerol (TG) concentration was reduced in both dietary fat groups. In conclusion, our results suggest that PA protects against oxidative stress-induced by genetic iron overload alone or when fed high fat. 相似文献
100.
Baljit Kaur Manju Sharma Rohit Soni H. S. Oberoi B. S. Chadha 《Applied biochemistry and biotechnology》2013,169(2):393-407
Thirty heterokaryons, formed by protoplast fusion of Aspergillus nidulans and Aspergillus tubingensis, were selected on the basis of their ability to grow on 2-deoxyglucose (0.2 %, w/v) and intermediate spore color. These heterokaryons were studied for cellulase production using shake flask and solid substrate cultures at 40 °C. Fusants 51 and 28 exhibited appreciably higher levels of endoglucanase, cellobiohydrolase, β-glucosidase, and FPase activities when compared with parental strains. Employing proteomic-based approaches, the differential expression of proteins in secretome of fusants and parental strains were analyzed using two-dimensional electrophoresis. The expression of some of the proteins in the fusants was found to be up/downregulated. The upregulated proteins in the fusant 51 were identified by liquid chromatography–mass spectroscopy as endoxylanase, endochitinase, β-glucosidase, as well as hypothetical proteins. The cellulases produced by fusants 28 and 51 showed improved saccharification of alkali treated rice straw when compared with the parental strains. 相似文献