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11.
S. N. Mishra D. Rambabu A. K. Grover R. G. Pillay P. N. Tandon H. G. Devare R. Vijayaraghavan 《Hyperfine Interactions》1986,28(1-4):471-474
57Fe Mössbauer and magnetization studies on a new series Fe4–2xRuxSix (1.0x1.7) are reported. The system is seen to transform from a collinear ferromagnet for x1.2 to a cluster spin glass for x>=1.54 In the intermediate region the magnetic behaviour of the system, as probed by the Mössbauer effect, is dominated by the presence of clusters and their dynamics. The alloys have large ordering temperatures ( 750 K) throughout the series except for x>1.54 where they drop sharply. The moment values, in contrast, fall sharply from 4.8B at x=1 to 0.5B at x=1.6C. The average value of the HF at57Fe measured at 15 K does not change significantly throughout the series. 相似文献
12.
The formation of palladium(II) complexes with aliphatic amines and their oxidation by chloramine‐T in perchloric acid medium has been studied. The spectrophotometric studies showed the formation of 1:1 and 1:2 complexes between palladium(II) and amine in absence of HClO4. An increase in [HClO4] in reaction mixture suppresses the complex formation and in presence of [HClO4] ~10?3 mol dm?3 only a 1:1 complex between palladium(II) and amine has been observed. The effect of Cl? on the complex formation has also been studied. Palladium(II)‐catalyzed oxidation of these amines by chloramine‐T showed a first‐order dependence of rate with respect to each—oxidant, substrate, catalyst, and H+. The mechanism consistent with kinetic data for the oxidation process has been proposed in absence as well as in presence of initial [Cl?]. © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 603–612, 2002 相似文献
13.
Singh Karamjeet Chebaane Saleh Ben Khalifa Sana Benabdallah Feres Ren Xiaobing Khemakhem Hamadi Grover Amit Singh Mehtab 《Wireless Networks》2022,28(3):1003-1016
Wireless Networks - Inter-satellite data transmission links are very crucial for providing global inter-connectivity. We report designing and investigations on high date rate inter-satellite... 相似文献
14.
4-Hydroxybenzofuran-3-ones show a large bathochromic shift in UV spectrum on the addition of sodium acetate. Such a large shift is not observed in 6-hydroxycompounds. 相似文献
15.
16.
Komuraiah Buduma Niranjana Kumar A Satya Srinivas KVN Kotesh Kumar J Srinivas Chinde Anand Kumar Domatti Yogesh Kumar Paramjit Grover Ashok Tiwari Feroz Khan 《Journal of heterocyclic chemistry》2021,58(11):2078-2089
Design, synthesis, and bioactivity evaluation of novel mannich bases ( 2a-2j ) and triazole-chalcone derivatives ( 7a-7k ) of Eugenol 1 were reported. Among all the derivatives tested for antiproliferative activity, di-amine manich derivative 2b (32.92 μM), and 4-methoxy chalcone triazole derivative 7d (33.05 μM) significantly inhibited HepG2 cell lines when compared to the standard doxorubicin (37.29 μM). Whereas most of the compounds such as diethylamine 2a (17.75 μM), (aminomethyl) methane diamine 2b (17.02 μM), and bis (chloromethyl) amine 2c (20.12 μM) showed moderate to better inhibition towards MCF-7 cell lines. The synthesized analogues were also tested for antidiabetic and antiobesity potentials. Compounds 2f (55.50%), 2c (54.34%), 7g (55.5%), and 2a (55.5%) have shown moderate inhibitory potentials toward intestinal α-glucosidase enzyme when compared to the standard Acarbose (72.86%). Likewise, compounds 7d (82.95%), 7f (76.19%), 7g (74.81%), 7e (74.81%), and 2g (72.50%) have shown significant to moderate inhibitory potentials toward Pancreatic lipase enzyme when compared to the standard orlistat (91.10%). ROS induces life-threatening diseases like diabetes, cancer, etc., and antioxidants play a major role in controlling their production. Compounds 2c (99.81%), 2i (99.80%), 2d (99.26%), 2g (98.79%), and 2f (98.42%) have shown significant antioxidant profiles in ABTS assay when compared to the standard Trolox (99.07%). Further, In silico Molecular docking and pharmacokinetic screening of the eugenol derivatives complemented the in vitro results indicating the drug likeness of the obtained active compounds. 相似文献
17.
Unprecedented cyclization was observed during N-sulfonylation of 3-[1-(phenylhydrazono)-ethyl]-chromen-2-one in pyridine, affording 3-methyl-1-phenylchromeno[4,3-c]pyrazol-4(1H)-ones. To avoid use of noxious pyridine, reaction was tried in different basic conditions and the best results were obtained with potassium carbonate in acetone. A wide range of substrates bearing either electron-donating or electron-withdrawing substituents on phenylhydrazine ring were compatible with the developed methodology. Rapid access of starting material, 3-acetylcoumarin, excellent yields of products, and use of environmentally benign base and solvent for the cyclization make this strategy an efficient and convenient method for synthesis of 3-methyl-1-phenylchromeno[4,3-c]pyrazol-4(1H)-ones. 相似文献
18.
Charles W. Teplin Sachit Grover Adrian Chitu Alexander Limanov Monical Chahal James Im Daniel Amkreutz Stefan Gall Heayoung P. Yoon Vincenzo Lasalvia Paul Stradins Kim M. Jones Andrew G. Norman David L. Young Howard M. Branz Benjamin G. Lee 《Progress in Photovoltaics: Research and Applications》2015,23(7):909-917
We fabricate thin epitaxial crystal silicon solar cells on display glass and fused silica substrates overcoated with a silicon seed layer. To confirm the quality of hot‐wire chemical vapor deposition epitaxy, we grow a 2‐µm‐thick absorber on a (100) monocrystalline Si layer transfer seed on display glass and achieve 6.5% efficiency with an open circuit voltage (VOC) of 586 mV without light‐trapping features. This device enables the evaluation of seed layers on display glass. Using polycrystalline seeds formed from amorphous silicon by laser‐induced mixed phase solidification (MPS) and electron beam crystallization, we demonstrate 2.9%, 476 mV (MPS) and 4.1%, 551 mV (electron beam crystallization) solar cells. Grain boundaries likely limit the solar cell grown on the MPS seed layer, and we establish an upper bound for the grain boundary recombination velocity (SGB) of 1.6x104 cm/s. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
19.
Dr. Uttam Dutta Sandip Porey Sandeep Pimparkar Astam Mandal Jagrit Grover Adithyaraj Koodan Dr. Debabrata Maiti 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(47):21017-21022
Biaryl compounds are extremely important structural motifs in natural products, biologically active components and pharmaceuticals. Selective synthesis of biaryls by distinguishing the subtle reactivity difference of distal arene C−H bonds are significantly challenging. Herein, we describe para-selective C−H arylation, which is acheived by a unique combination of a meta-directing group and norbornene as a transient mediator. Upon direct meta-C−H palladation, one-bond relay palladation occurs in presence of norbornene and subsequently para-C−H arylation is achieved for sulfonates, phosphonates and phenols bearing 2,6-disubstitution patterns. The protocol is amenable to electron-deficient aryl iodides. Multisubstituted arenes and phenols are obtained by postsynthetic modification of the products. The protocol allows the synthesis of hexa-substituted benzene by sequential selective distal C−H functionalization. 相似文献
20.
Ramandeep Kaur Heena Ripneel Kaur Aman Grover Susheela Rani Ashok Kumar Malik Abuzar Kabir Kenneth G. Furton 《Journal of separation science》2020,43(13):2626-2635
A simple, fast, and sensitive analytical protocol using fabric‐phase sorptive extraction followed by high performance liquid chromatography with ultraviolet detection has been developed and validated for the extraction of five parabens including methylparaben, ethylparaben, propylparaben, butylparaben, and benzylparaben. In the present work, sol‐gel polyethylene glycol coated fabric‐phase sorptive extraction membrane is used for the preconcentration of parabens (polar) from complex matrices. The use of fabric‐phase sorptive extraction membrane provides a high surface area which offers high sorbent loading, shortened equilibrium time, and overall decrease in the sample preparation time. Various factors affecting the performance of fabric‐phase sorptive extraction, including extraction time, eluting solvent, elution time, and pH of the sample matrix, were optimized. Separation was performed using a mobile phase consisting of water:acetonitrile (63:37; v/v) at an isocratic elution mode at a flow rate of 0.9 mL/min with wavelength at 254 nm. The calibration curves of the target analytes were prepared with good correlation coefficient values (r2 > 0.9955). The limit of detection values range from 0.252 to 0.580 ng/mL. Finally, the method was successfully applied to various cosmetics and personal care product samples such as rose water, deodorant, hair serum, and cream with extraction recoveries ranged between 88 and 122% with relative standard deviation <5%. 相似文献