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51.
Mudigonda K Jukanti R Apte SS Ajjala DR Shrivastava W Kandikere VN Nirogi RV 《Biomedical chromatography : BMC》2006,20(10):1028-1032
A rapid, reliable HPLC method with UV detection (240 nm) was developed and validated for quantitation of saquinavir in mice brain and testis. Saquinavir and the internal standard were isolated from homogenized tissue matrices using liquid-liquid extraction procedure and were then analyzed using an isocratic mobile phase by reversed-phase liquid chromatography. The lower limit of quantification was 50 ng/g for both brain and testis. A linear dynamic range of 50-5000 ng/g for both brain and testis was established. This HPLC method was validated with between-batch precision of 0.5-4.4 and 1.5-5.5% for brain and testis, respectively. The between-batch accuracy was 94.7-105.9% and 97.5-105.0% for brain and testis, respectively. The present method was applied for tissue distribution studies of the novel drug delivery systems of saquinavir in mice. 相似文献
52.
Nirogi RV Kandikere VN Shrivastava W Mudigonda K Datla PV 《Rapid communications in mass spectrometry : RCM》2006,20(8):1225-1230
A simple, sensitive and rapid high-performance liquid chromatography/negative ion electrospray tandem mass spectrometry method was developed and validated for the assay of fluvastatin in human plasma. Following solid-phase extraction, the analytes were separated using an isocratic mobile phase on a reversed-phase column and analyzed by mass spectrometry in the multiple reaction monitoring mode using the respective [M-H]- ions, m/z 410/348 for fluvastatin and m/z 480/418 for the internal standard. The assay exhibited a linear dynamic range of 2-500 ng/mL for fluvastatin in human plasma. The lower limit of quantification was 2 ng/mL with a relative standard deviation of less than 5%. Acceptable precision and accuracy were obtained for concentrations over the standard curve range. A run time of 1.5 min for each sample made it possible to analyze more than 400 human plasma samples per day. The validated method has been successfully used to analyze human plasma samples for application in pharmacokinetic, bioavailability or bioequivalence studies. 相似文献
53.
V. Kumar A.K. Shrivastava Vijeta Jha 《Journal of Physics and Chemistry of Solids》2010,71(11):1513-1520
Using the plasma oscillations theory of solids, simple relations have been proposed for the calculation of bulk modulus (B) and microhardness (H) of group IV, II-VI, III-V, I-III-VI2 and II-IV-V2 semiconductors with tetrahedral structure. We find that B=K1 (?ωp)2.3333 and H=K2 (?ωp)2.3333−K3, where K1, K2 and K3 are the constants. The numerical values of K1, K2 and K3 are respectively, 0.141, 0.036 and 12.895 for group IV, 0.109, 0.0037 and 0.782 for II-VI, 0.125, 0.0202 and 5.743 for III-V, 0.109, 0.0065 and 1.160 for I-III-VI2, and 0.125, 0.0359 and 15.310 for II-IV-V2 semiconductors. The calculated values of B and H are compared with the experimental values and the values reported by different workers. Reasonably good agreement has been obtained between them. 相似文献
54.
A.M. Samant S. Kailas A. Chatterjee A. Shrivastava A. Navin P. Singh 《The European Physical Journal A - Hadrons and Nuclei》2000,7(1):59-64
The fission fragment angular distributions have been measured for the system 19F +209Bi over a range of bombarding energies from 88.0 MeV to 125.6 MeV. The measured fission fragment anisotropies are in agreement
with the saddle point statistical model calculations in the above energy range. Combining these data with those available
for 11B, 12C, 14N, 16O and 18O +209Bi, 208Pb systems, it is concluded that the spherical target plus projectile systems behave “normal” from near- to above – barrier
energies. This observation is in contrast to the “anomalous” anisotropies exhibited by the deformed actinide target – projectile
systems at near – barrier energies.
Received: 5 May 1999 / Revised version: 25 July 1999 相似文献
55.
JPC – Journal of Planar Chromatography – Modern TLC - The phytochemical fingerprint profile of ammoniacum gum (from Dorema ammoniacum) was defined by subjecting different extracts of... 相似文献
56.
T. Zerguerras B. Blank Y. Blumenfeld T. Suomijärvi D. Beaumel B. A. Brown M. Chartier M. Fallot J. Giovinazzo C. Jouanne V. Lapoux I. Lhenry-Yvon W. Mittig P. Roussel-Chomaz H. Savajols J. A. Scarpaci A. Shrivastava M. Thoennessen 《The European Physical Journal A - Hadrons and Nuclei》2004,20(3):389-396
Light proton-rich bound and unbound nuclei were produced by means of stripping reactions of secondary beams of 20Mg and 18Ne. The decays of the unbound nuclei 18,19Na have been measured by detecting their decay products 17,18Ne and one proton and by performing an invariant-mass reconstruction. For 18Na, the present work is the first measurement of its decay. As the decay scheme of this nucleus could not be determined, two possible scenarios are proposed and discussed. In addition, the decay of excited states in 17Ne via two-proton emission was observed. The proton-proton angular distribution is isotropic for the first two-proton-emitting states, whereas higher-lying states seem to decay by a correlated two-proton emission, consistent with a 2He emission pattern for part of the decay strength.Received: 30 September 2003, Revised: 27 November 2003, Published online: 2 June 2004PACS:
21.10.-k Properties of nuclei; nuclear energy levels - 23.40.-s
decay; double
decay; electron and muon capture - 23.50. + z Decay by proton emissionM. Chartier: Present address: Physics Department, University of Liverpool, Liverpool, UK.M. Fallot: Present address: SUBATECH, Ecole des Mines, BP 20722, F-44307 Nantes Cedex, France.A. Shrivastava: Permanent address: Bhabha Atomic Research Center, Mumbai, India.Experiment performed at the GANIL facility, Caen, France. 相似文献
57.
Mechanoluminescence spectra of triglycine sulfate, guanidine aluminium sulfate, rochelle salt, diglycine manganous chloride
dihydrate, lithium ammonium tartate monohydrate and potassium dihydrogen phosphate crystals resemble the discharge spectra
of nitrogen gases. Glycine silver nitrate, thiourea, ammonium sulfate and azobenzene crystals, the structure of which is centrosymmetric
at room temperature, do not show mechanoluminescence. Following the role of crystal structure, the mechanoluminescence excitation
is discussed on the basis of the piezo-electrification of the new surfaces created during fracture of the crystals. 相似文献
58.
The electron paramagnetic resonance of Mn2+ in KNO3 single crystal is investigated over a temperature cycle through transition temperatures. The hyperfine coupling constant, A, half width,Δ H, and the line intensity, I, are found to show sudden changes at the transition temperature, at whichα-KNO3 changes intoβ-KNO3. The lines are much sharper in the high temperatureβ-phase than inα-phase of the crystal. They are explained, qualitatively, in terms of structure change and rotation of NO 3 ? ions. The spectra in the two phases,α andβ, are analysed in terms of usual spin-Hamiltonian. A search of metastableγ-phase is also made and probable indications for the same are found. 相似文献
59.
The core and overlap contributions to the electronic charge density at the 107Ag nucleus in AgF and AgCl lattices are calculated as a function of the interatomic distance. 相似文献
60.
Using Bohm and Pines theory of plasma oscillations in solids the relative intensities of the Mg KVβ and Al KVIβ satellites have been estimated as 0.89% and 0.61% respectively. These values are in close agreement with the experimental values reported by Kunzl. 相似文献