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11.
12.
Dwivedi Jyotsana Gupta Abhishek Verma Shikhar Paliwal Sarvesh Rawat Ajay Kumar Singh 《平面色谱法杂志一现代薄层色谱法》2019,32(2):103-108
JPC – Journal of Planar Chromatography – Modern TLC - A high-performance thin-layer chromatography (HPTLC) method for the simultaneous quantitative determination and validation of... 相似文献
13.
Vijay Narayan Anoop Kumar Pandey Apoorva Dwivedi Benard Samwel Mwankemwa Avantika Maurya Ankit Kumar Sharma Vijay Singh 《印度化学会志》2022,99(8):100580
Uracil mustard belongs to the nitrogen mustard family and is primarily used in anticancer drugs. The research that follows, investigates many quantum chemical features such as the computation of global minimum energies with no negative wavenumber values using the Density Functional Theory (DFT) with Becke three functional and 6-311G (d, p)/6–311++G (d, p) basis sets. All the vibrational modes have been calibrated and justified in comparison to their experimental counterparts. Mustard's polarizability and hyperpolarizability components, Natural Bond Analysis (NBO), electronic properties, Fukui function analysis, various global parameters, Quantum Theory of Atoms In Molecule (QTAIM) analysis, ADMET analysis, and docking analysis have all been investigated using the same theory and basis sets, indicating its biochemical significance. The biological activity of the molecule is reported by using PASS software. The Full fitness score and binding affinity parameters are utilized to determine the binding strength with 6cq3 protein. The acidity of the title molecule is calculated in water solvent by polarizable continuum model (PCM) solvent effects (estimated in water). The HOMO, LUMO, and MESP plots are used to explore the nature of binding and surfaces. The Fukui functions are computed using Mulliken atomic charges for neutral atoms, cations, and anions. The Ultraviolet–visible (UV–vis) of the molecule is computed employing the TD-DFT method. 相似文献
14.
Jigar Panchal Sonika Jain Pankaj Kumar Jain Dharma Kishore Jaya Dwivedi 《Journal of heterocyclic chemistry》2021,58(11):2049-2066
The greener methodology to synthesize s-triazine derivatives (also known as TCT) is described, including synthesis through microwave, ultrasound, and solvent-free conditions. This review mainly focuses on reactions of TCT (2,4,6-trichloro-1,3,5-triazine) with various substituents having amine and hydroxy functionalities to give corresponding triazine derivatives under a greener approach. The results of reactions indicate that, unlike classical methods, green methods result in better yields of the product, through a rapid reaction, under mild reaction conditions, and by easy workup procedures. 相似文献
15.
Latent damage tracks of energetic40Ar ions (18·56 MeV/u) have been recorded in Lexan polycarbonate detector. Bulk and track-etch parameters are evaluated under successive chemical
etching. Our results show a linear correlation between the measured track-etch rate along the track and the corresponding
total energy-loss rate and predict a threshold value of 5·0 MeV mg−1 cm2 for track registration. Maximum etchable track lengths of40Ar ions as a function of energies have also been measured and compared with three different sets of theoretical ranges. 相似文献
16.
A. GARAY S. DEMETER K. KOVÁCS G. HORVÁTH ÁGNES FALUDI-DÁNIEL 《Photochemistry and photobiology》1972,16(2):139-144
Abstract— Circular dichroism (CD) spectra were studied in System I particles prepared by digitonin fragmentation of chloroplasts of normal maize and carotenoid-deficient mutants. CD bands of pigment molecules were found to be higher in particles than in solutions. This phenomenon was most pronounced for the particles containing the carotenoid composition of normal chloroplast lamellae. The CD signal of chlorophylls bound to particles of carotenoid-deficient chloroplasts was closer to that found in solutions. This indicates that aggregation and/or binding of chlorophylls in carotenoid-deficient mutants may be less extensive than in normal chloroplasts. 相似文献
17.
Various empirical theories of ultrasonic velocity have been applied to three binary liquid mixtures, under pressures up to
200 MPa and their validity have been tested. A pressure dependent study of ultrasonic velocities has been made at 303.15 K.
The agreement between theory and experiment is found to be quite satisfactory. 相似文献
18.
C B Dwivedi 《Pramana》2000,55(5-6):849-854
Theoretical prediction of a new kind of normal mode behaviour of electro-mechanical nature was first time reported by Dwivedi
and Das in 1992 in the context of mesospheric modeling of observed neutral induced turbulence. Local dynamo action (due to
relative neutral flow) governs the basic physical principle for linear excitation of the neutral induced low frequency instability
(NILF) in mesospheric plasma, which comprises of weakly ionized inhomogeneous gas confined by the external gravity and ambient
magnetic field. The present contribution offers physical explanation in terms of dynamo transformation of neutral drag effect
as a source to understand complete suppression of the usual collisional R-T and in turn linear driving of the NILF. It is
therefore emphasized, worth calling it as the dynamo instability. 相似文献
19.
We study projective curvature tensor in K-contact and Sasakian manifolds. We prove that (1) if a K-contact manifold is quasi projectively flat then it is Einstein and (2) a K-contact manifold is ξ-projectively flat if and only if it is Einstein Sasakian. Necessary and sufficient conditions for a K-contact manifold to be quasi projectively flat and φ-projectively flat are obtained. We also prove that for a (2n + 1)-dimensional Sasakian manifold the conditions of being quasi projectively flat, φ-projectively flat and locally isometric to the unit sphere S
2n+1 (1) are equivalent. Finally, we prove that a compact φ-projectively flat K-contact manifold with regular contact vector field is a principal S
1-bundle over an almost Kaehler space of constant holomorphic sectional curvature 4. 相似文献
20.
The modal dispersion characteristics of EM waves in a new unconventional plasma loaded doubly clad waveguide having a shape of the lemniscates of Bernoulli-type core cross-section have been studied analytically. The proposed waveguide has three parts namely the core with slighter high index, the inner cladding with plasma and the outer cladding with air. Now using the necessary orthogonal coordinates for the proposed structure and imposing the boundary conditions under the weak guidance condition, the modal characteristics equation has been obtained considering variations in plasma width and plasma frequency, the dispersion curves and cutoff frequencies have been obtained and presented in this paper. It is noted that as the width of plasma layer increases, the cutoff frequency also increases considerably in all considered cases. This shows that using plasma width as a new parameter we can control any particular mode on our wish. 相似文献