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81.
K. Prashanthi B.A. Chalke K.C. Barick A. Das I. Dhiman V.R. Palkar 《Solid State Communications》2009,149(5-6):188-191
La doping at Bi Site in multiferroic BiFeO3 (BFO) is known to stabilize the ferroelectric perovskite phase and reduce the leakage current. It has been observed that in Dy modified BFO sample, La is not required for the said reason. In fact, the removal of La from Dy modified BFO system leads to the reduction in leakage current. Moreover, the magnetic properties are enhanced by order of magnitude in the absence of La in the system. Remarkably, a similar trend in properties has been also observed in thin films grown on Pt/TiO2/SiO2/Si substrate by using the pulsed laser deposition technique. This significant variation in the properties after removal of La from the system could be attributed to the change in lattice parameters, bond lengths and Fe–O–Fe bond angle as determined by powder x-ray and neutron diffraction study. 相似文献
82.
A validated LC‐MS/MS assay for simultaneous quantification of methotrexate and tofacitinib in rat plasma: application to a pharmacokinetic study
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Kuldeep Sharma Kalpeshkumar Giri Vinay Dhiman Abhishek Dixit Mohd Zainuddin Ramesh Mullangi 《Biomedical chromatography : BMC》2015,29(5):722-732
A highly sensitive, specific and rapid LC‐ESI‐MS/MS method has been developed and validated for simultaneous quantification of methotrexate (MTX) and tofacitinib (TFB) in rat plasma (50 μL) using phenacetin as an internal standard (IS), as per the US Food and Drug Administration guidelines. After a solid‐phase extraction procedure, the separation of the analytes and IS was performed on a Chromolith RP18e column using an isocratic mobile phase of 5 m m ammonium acetate (pH 5.0) and acetonitrile at a ratio of 25:75 (v/v) using flow‐gradient with a total run time of 3.5 min. The detection was performed in multiple reaction monitoring mode, using the transitions of m/z 455.2 → 308.3, m/z 313.2 → 149.2 and m/z 180.3 → 110.2 for MTX, TFB and IS, respectively. The calibration curves were linear over the range of 0.49–91.0 and 0.40–74.4 ng/mL for MTX and TFB, respectively. The intra‐ and interday accuracy and precision values for MTX and TFB were <15% at low quality control (QC), medium QC and high QC and <20% at lower limit of quantification. The validated assay was applied to derive the pharmacokinetic parameters for MTX and TFB post‐dosing of MTX and TFB orally and intravenously to rats. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
83.
Matiur Rahman Avik Kr. Bagdi Dhiman Kundu Adinath Majee Alakananda Hajra 《Journal of heterocyclic chemistry》2012,49(5):1224-1228
4‐(1‐Imidazolium) butane sulfonate is an excellent catalyst for the synthesis of 2,4,5‐trisubstituted and 1,2,4,5‐tetrasubstituted imidazoles through the condensation of 1,2‐dicarbonyl compounds, aldehydes, and ammonium acetate or amine via multicomponent condensation strategy under solvent‐free conditions. The key advantages of this process are high yields, reusability of catalyst, environmental friendliness, easy work‐up and purification of products by nonchromatographic methods. 相似文献
84.
Chavan Pramod V. Pandit Kapil S. Desai Uday V. Wadgaonkar Prakash P. Nawale Laxman Bhansali Sujit Sarkar Dhiman 《Research on Chemical Intermediates》2017,43(10):5675-5690
Research on Chemical Intermediates - A series of spirochromene-tethered 1,2,3-triazoles (1,2,3-triazolylspirochromenes) were designed and synthesized via click-chemistry-based one-pot... 相似文献
85.
86.
J.R. GuptaJoginder S. Dhiman M.G. Gorla 《Journal of Mathematical Analysis and Applications》2002,276(2):882-895
The amenability of the linear stability analysis for the magnetohydrodynamic thermal stability problem in completely confined fluids carried by Gupta and Dhiman [J. Math. Anal. Appl. 262 (2001) 221-228] for extension to the magnetohydrodynamic thermohaline stability problems of Veronis and Stern type configurations is shown to yield some general qualitative mathematical results concerning the character of marginal state, stability of oscillatory motions and limitations on the oscillatory motions of growing amplitude, which to the best of our knowledge do not appear to have been reported earlier in the literature on thermohaline stability problem with the same degree of generality. 相似文献
87.
Tanvi?Dhiman Charanjeet?SinghEmail author Maalti?Puri Harpreet?Kaur Randeep?Kaur S.?Bindra Narang 《The European Physical Journal B - Condensed Matter and Complex Systems》2015,88(10):271
The microwave characteristics of Pb1?x Ca x Fe0.5Nb0.5O3 multiferroics (x = 0.0, 0.4, 0.45, 0.5, 0.55, 0.6), have been investigated as a function of frequency and substitution. The results depict ?13.99 dB reflection loss at 11.65 GHz in composition x = 0.6. Microwave absorption is enhanced with substitution of Ca2+ ions and undoped composition 0.0 behaves as electromagnetic shield. The model governing microwave absorption is discussed and different compositions for electromagnetic applications have been suggested. 相似文献
88.
P. K. Raina A. Shukla P. K. Rath B. M. Dix K. Chaturverdi R. Chandra S. K. Dhiman A. J. Singh 《Physics of Atomic Nuclei》2004,67(11):2021-2026
The quality of Hartree-Fock-Bogolyubov wave functions is tested by comparing the theoretically calculated results with the available experimental data for a number of spectroscopic properties like yrast spectra, reduced B(E2) transition probabilities, quadrupole moments, and g factors for the nuclei involved in 2νββ decay. It is observed that the np interactions vis-à-vis the deformations of the intrinsic ground states of medium-mass nuclei play a crucial role in the fine tuning of the nuclear matrix elementsM2ν. 相似文献
89.
Joginder S Dhiman 《Proceedings Mathematical Sciences》2000,110(3):335-345
Recently discovered hydrodynamic instability [1], in a simple Bénard configuration in the parameter regime
under the action of a nonadverse temperature gradient, is shown to be suppressed by the simultaneous action of a uniform
rotation and a uniform magnetic field both acting parallel to gravity for oscillatory perturbations whenever (Qσ
1/π2 + J/π4) > 1 and the effective Rayleigh numberR(1 -T
0α2) is dominated by either 27π4(1 + l/σ1/4 or 27π4/2 according as σ1 ≥1 or σ1
≤ 1 respectively. HereT
0is the temperature of the lower boundary while α2 is the coefficient of specific heat at constant volume due to temperature variation and σ1,R,Q andJ respectively denote the magnetic Prandtl number, the Rayleigh number, the Chandrasekhar number and the Taylor number. 相似文献
90.
This paper studies Rayleigh-Bénard convection of micropolar fluid layer heated from below with realistic boundary conditions. A specific approach for stability analysis of a convective problem based on variational principle is applied to characterize the Rayleigh number for quite general nature of bounding surfaces. The analysis consists of replacing the set of field equations by a variational principle and the expressions for Rayleigh number are then obtained by using trial function satisfying the essential boundary conditions. Further, the values of the Rayleigh number for particular cases of large and small values of the microrotation coefficient have been obtained. The effects of wave number and micropolar parameter on the Rayleigh numbers for onset of stationary instability for each possible combination of the bounding surfaces are discussed and illustrated graphically. The present analysis establishes that the nature of bounding surfaces combination and microrotation have significant effect on the onset of convection. 相似文献