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201.
Desai Namita D. Singh Pirthipal P. Amin Purnima D. Jain Satishkumar P. 《Chromatographia》2009,69(3-4):385-388
This paper discusses the development of a stability-indicating reversed-phase LC method for analysis of cholecalciferol as the bulk drug and in formulations. The mobile phase was acetonitrile–methanol–water 50:50:2 (v/v). The calibration plot for the drug was linear in the range 0.4–10 μg mL−1. The method was accurate and precise with limits of detection and quantitation of 64 and 215 ng, respectively. Mean recovery was 100.71%. The method was used for analysis of cholecalciferol in pharmaceutical formulations in the presence of its degradation products and commonly used excipients.
相似文献202.
203.
Viktor Takts F.C. Miller Himanshu Jain C. Cserhti I.A. Szab D. Beke S. Kokenyesi 《Journal of Non》2009,355(37-42):1849-1852
Investigations of light-induced volume expansion and surface pattern recording in amorphous chalcogenide layers and nano-layered structures (NLS) were extended to direct electron-beam recording on Se/As2S3 and Sb/As2S3 NLS. Light as well as e-beam induced bleaching occurs in all NLS, while volume expansion occurs only in chalcogenide–chalcogenide NLS and in homogeneous Se or As2S3 layers. Comparison of these two phenomena revealed the possible role of purely electronic and thermal processes in the interdiffusion and relief formation. The latter is supposed to be connected with radiation-induced defect creation, free volume increase under the increased fluidity conditions as well as with the possible additional influence of electrostatic forces and stress. 相似文献
204.
Treatment of [PtCl2(Ptolyl3)2] (tolyl = 4-MeC6H4) with Na2S in benzene gave [Pt2(μ2-S)2(Ptolyl3)4] (1), which is soluble in common organic solvents. Reactions of (1) with various metal complexes have been studied and several polynuclear metal aggregates isolated. These new complexes were
characterized by elemental analysis and n.m.r. spectroscopy.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
205.
Periodic orbits belonging to the stromgren families A, B and C around the collinear libration points in the restricted three
body problem have been studied when the smaller primary is a triaxial rigid body and more massive body is a source of radiation
pressure. These families are determined in three different cases: (i) classical case, (ii) when bigger primary is a source
of radiation pressure, (iii) when smaller primary is a triaxial rigid body and bigger primary is a source of radiation pressure.
The Liapunov stability of each periodic solution has also been examined.
相似文献
206.
LI GuangShun ZHOU XiaoHong ZHANG ShuangQuan ZHANG YuHu & MENG Jie Institute of Modern Physics Chinese Academy of Sciences Lanzhou China Graduate University of Chinese Academy of Sciences Beijing School of Physics SK Laboratory of Nuclear Physics & Technology Peking University Beijing 《中国科学:物理学 力学 天文学(英文版)》2011,(Z1)
Theoretical calculations have been performed for the ν9/2+[624](i13/2) and ν7/2-[503](f7/2) bands of 185Pt in the framework of particle-rotor model. The band properties of signature splitting and configuration mixing have been analyzed. The level energy and signature splitting before the band crossing can be well interpreted by introducing triaxiality. The positive-parity yrast band is pro posed to be dominated by the ν9/2+[624](i13/2) component, while the negative-parity band shows strong mixing of ν7/2-[5... 相似文献
207.
Rajendra N. Goyal Neena Jain Vibha Gurnani 《Monatshefte für Chemie / Chemical Monthly》2001,132(5):575-585
Summary. The electrochemical behaviour of chlorpromazine has been examined in phosphate buffers in aqueous as well as micellar media
at a pyrolytic graphite electrode surface. Two oxidation peaks were obtained in linear sweep voltammetry of chlorpromazine.
The first peak corresponds to the formation of the cationic free radical, which on further 1e−-oxidation gives a dication. The spectroscopic changes and kinetics of the cationic free radical and dication species generated
during electrooxidation of chlorpromazine were investigated in both media. The decay of the dication was studied chronoamperometrically
and was found to follow first-order kinetics with a half-life of ∼25 ms. Surfactants affect both E
p and i
p values. The anionic surfactant SDS has been found to catalyze the reaction of the free radical cation and the dication. 相似文献
208.
We use lookback time versus redshift data from galaxy clusters (Capozziello et al., 2004 [9]) and passively evolving galaxies (Simon et al., 2005 [62]), and apply a Bayesian prior on the total age of the Universe based on WMAP measurements, to constrain dark energy cosmological model parameters. Current lookback time data provide interesting and moderately restrictive constraints on cosmological parameters. When used jointly with current baryon acoustic peak and Type Ia supernovae apparent magnitude versus redshift data, lookback time data tighten the constraints on parameters and favor slightly smaller values of the nonrelativistic matter energy density. 相似文献
209.
Multiple UAVs path planning algorithms: a comparative study 总被引:1,自引:0,他引:1
B. Moses Sathyaraj L. C. Jain A. Finn S. Drake 《Fuzzy Optimization and Decision Making》2008,7(3):257-267
Unmanned aerial vehicles (UAVs) are used in team for detecting targets and keeping them in its sensor range. There are various
algorithms available for searching and monitoring targets. The complexity of the search algorithm increases if the number
of nodes is increased. This paper focuses on multi UAVs path planning and Path Finding algorithms. Number of Path Finding
and Search algorithms was applied to various environments, and their performance compared. The number of searches and also
the computation time increases as the number of nodes increases. The various algorithms studied are Dijkstra’s algorithm,
Bellman Ford’s algorithm, Floyd-Warshall’s algorithm and the AStar algorithm. These search algorithms were compared. The results
show that the AStar algorithm performed better than the other search algorithms. These path finding algorithms were compared
so that a path for communication can be established and monitored. 相似文献
210.
The pressure—volume—temperature properties of a series of copolymers ranging in content from 18 to 40 wt % of vinyl acetate, and up to a maximum pressure of 1800 kg/cm2 are studied. The results for the melt state can be satisfactorily fitted by the scaled equation of state, developed previously and applied to single-component systems and to mixtures. The dependence of the scaling parameters for the copolymers on composition deviates from that expected for a mixture, where volumes at elevated pressures can be predicted without further recourse to experiment. These differences are discussed in terms of the sequential structure of the copolymer chain and its series of interfaces between the two species. 相似文献