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81.
Neeraj Shukla Saurabh K. BoseMihir Sarkar Nobin BanerjiAnjan K. Gupta Harish C. Verma 《Journal of magnetism and magnetic materials》2012
2 MeV protons and 1 MeV carbon ions are bombarded on highly oriented pyrolytic graphite (HOPG) samples and their electronic transport measurements are carried out in the presence of magnetic field. The Magneto-Resistance (MR) measurements show measurable hysteresis in the resistance value after ion beam irradiation for the in-plane magnetic field direction as well as for the out-of-plane field direction. The MR depends on the thickness of the flake and the method of its separation from the bulk HOPG. The results substantiate that the ferromagnetic coupling between the magnetic moments at the vacancy defect sites in HOPG sensitively depends on the average defect separation. The average defect separation range of 1.7–0.5 nm allows only a part of the 40 μm thick proton beam irradiated sample to go for ferromagnetic ordering. Similar conclusions are drawn from carbon ion irradiated HOPG flake. The irradiation increases the resistance of the flake as well. 相似文献
82.
Nirupam Das Biswajit Dash Meenakshi Dhanawat Sushant Kumar Shrivastava 《Chemical Papers》2012,66(1):67-74
Ten derivatives of N1 substituted/unsubstituted 5-(4-chlorophenyl)-3-(2-thienyl) pyrazoline were synthesised from chalcone-like
intermediate and substituted phenyl hydrazines, hydrazine hydrate, and semi/thiosemicarbazide. The chemical structure of compounds
was confirmed by means of IR, 1H NMR, mass spectroscopy, and elemental analysis. The antidepressant and anticonvulsant activities were investigated by Porsolt’s
behavioural despair test (forced swimming) and maximum electroshock seizure test, respectively. Rota-Rod test was performed
to assess any probable changes in motor coordination induced by the test compounds. Four compounds (IId, IIg, IIi, and IIj) exhibited good activity profile against depression and docking studies confirmed their consensual interaction with monoamine
oxidase A. In addition, compounds IIc and IIe showed protection against MES-induced seizures. 相似文献
83.
Prashant T. Mistry Nimesh R. Kamdar Dhaval D. Haveliwala Saurabh K. Patel 《Journal of heterocyclic chemistry》2012,49(2):349-357
A variety of pyrano[2,3‐d]pyrimidine‐5‐one derivatives 5 , 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j , 6 , 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h , 6i , 6j have been synthesized from 6‐amino‐4‐(substituted phenyl)‐5‐cyano‐3‐methyl‐1‐phenyl‐1,4‐dihydropyrano[2,3‐c]pyrazole derivatives 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 4i , 4j via cyclization using formic acid and acetic acid. All the newly synthesized compounds have been characterized by IR, 1H NMR, 13C NMR, and elemental analysis. All the synthesized compounds have been screened for antibacterial, antifungal and antitubercular activity. J. Heterocyclic Chem., (2012). 相似文献
84.
Dhruba Gupta C Samanta R Kanungo P Basu Subinit Roy S Kailas A Chatterjee B J Roy K Mahata A Samant A Shrivastava 《Pramana》2001,57(1):209-213
Inclusive cross sections of α particles and tritons from the breakup of 42 MeV 7Li by 12C and 197Au targets are presented and analysed in the framework of the Serber model. Spectral distortions due to the targets and relevant
reaction mechanisms are discussed. 相似文献
85.
Purnima Shrivastava 《PAMM》2007,7(1):2150043-2150044
Simulating the heat conduction in between a solid conducting body immersed in fluid at a given temperature is a difficult task, particularly when the body is tapered in shape and the costs have to be kept low. The body in question is cylindrical, symmetrical about z-axis, tapered in shape and has been heated to a high temperature before being immersed into the fluid. The heat conduction equation in cylindrical polar coordinates with all derivative boundary conditions is attempted to be solved in two ways – first analytically making use of Bessel's function and then by numerical modelling with the help of Finite Difference method, and equations thus formed have been solved through ADI explicit and Implicit (Peaceman Rachford) scheme on microcomputer. The paper is an account of work already done on this and includes further possibilities for general solution with analytical methods and a suitable low-cost numerical solution. Also possible analogy with flow of fluids have been explored. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
86.
Ritu Karwasra Shaban Ahmad Nagmi Bano Sahar Qazi Khalid Raza Surender Singh Saurabh Varma 《Molecules (Basel, Switzerland)》2022,27(18)
Punicalagin is the most bioactive pomegranate polyphenol with high antioxidant and free-radical scavenging activity and can potentially cure different ailments related to the cardiovascular system. The current research work was envisioned to predict the targeting efficiency of punicalagin (PG) nanoparticles to the macrophages, more specifically to bone marrow macrophages. For this, we selected mannose-decorated PLGA-punicalagin nanoparticles (Mn-PLGA-PG), and before formulating this nanocarrier in laboratory settings, we predicted the targeting efficiency of this nanocarrier by in silico analysis. The analysis proceeded with macrophage mannose receptors to be acquainted with the binding affinity and punicalagin-based nanocarrier interactions with this receptor. In silico docking studies of macrophage mannose receptors and punicalagin showed binding interactions on its surface. PG interacted with hydrogen bonds to the charged residue ASP668 and GLY666 and polar residue GLN760 of the Mn receptor. Mannose with a docking score of −5.811 Kcal/mol interacted with four hydrogen bonds and the mannose receptor of macrophage, and in PLGA, it showed a −4.334 Kcal/mol docking score. Further, the analysis proceeded with density functional theory analysis (DFT) and HOMO–LUMO analysis, followed by an extensive 100 ns molecular dynamics simulation to analyse the trajectories showing the slightest deviation and fluctuation. While analysing the ligand and protein interaction, a wonderful interaction was found among the atoms of the ligand and protein residues. This computational study confirms that this nanocarrier could be a promising lead molecule to regulate the incidence of drug-induced neutropenia. Furthermore, experimental validation is required before this can be stated with complete confidence or before human use. 相似文献
87.
The Ramanujan Journal - In Maier and Tenenbaum (Invent Math 76(1):121–128, 1984), Tenenbaum and the first author proved an old conjecture of Paul Erd?s about the propinquity of divisors... 相似文献
88.
Joshua W. M. MacMillan Katherine M. Marczenko Prof. Dr. Erin R. Johnson Prof. Dr. Saurabh S. Chitnis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(71):17134-17142
The addition of Sb−H bonds to alkynes was reported recently as a new hydroelementation reaction that exclusively yields anti-Markovnikov Z-olefins from terminal acetylenes. We examine four possible mechanisms that are consistent with the observed stereochemical and regiochemical outcomes. A comprehensive analysis of solvent, substituent, isotope, additive, and temperature effects on hydrostibination reaction rates definitively refutes three ionic mechanisms involving closed-shell charged intermediates. Instead the data support a fourth pathway featuring open-shell neutral intermediates. Density-functional theory (DFT) calculations are consistent with this model, predicting an activation barrier that is in agreement with the experimental value (Eyring analysis) and a rate limiting step that is congruent with the experimental kinetic isotope effect. We therefore conclude that hydrostibination of arylacetylenes is initiated by the generation of stibinyl radicals, which then participate in a cycle featuring SbII and SbIII intermediates to yield the observed Z-olefins as products. This mechanistic understanding will enable rational evolution of hydrostibination as a synthetic methodology. 相似文献
89.
A gauge-invariant Rarita-Schwinger theory of a massive spin-3/2 particle interacting with external electromagnetic, gravitational and dilaton fields is obtained by Kaluza-Klein reduction of a massless Rarita-Schwinger theory with graviational interaction. Fermionic gauge invariance serves to determine the background equations of motion. The couplings with external fields obtained by the Kaluza-Klein reduction are shown to lead to the absence of the classical Velo-Zwanziger problem and on quantizing using Dirac's procedure, the field anticommutators are found to be positive definite. 相似文献
90.
Saurabh D Rindani 《Pramana》1995,45(1):263-276
The prospects of experimental detection ofCP violation ate + e ? and\(pp/p\bar p\) colliders are reviewed. After a general discussion on the quantities which can measureCP violation and on the implications of theCPT theorem, various possibilities of measuringCP violation arising outside the standard model are taken up.CP violation in leptonic processes, especially polarization effects ine + e ?→l + l ? are discussed next.CP violation in\(t\overline t \) andW + W ? production and decay is also described. 相似文献