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901.
902.
A. Agarwal A. Sheoran S. Sanghi V. Bhatnagar S.K. Gupta M. Arora 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(3):964-969
Glasses with compositions xNb2O5·(30 ? x)M2O·69B2O3 (where M = Li, Na, K; x = 0, 4, 8 mol%) doped with 1 mol% V2O5 have been prepared using normal melt quench technique. The IR transmission spectra of the glasses have been studied over the range 400–4000 cm?1. The changes caused by the addition of Nb2O5 on the structure of these glasses have been reported. The electron paramagnetic resonance spectra of VO2+ ions in these glasses have been recorded in X-band (9.14 GHz) at room temperature (300 K). The spin Hamiltonian parameters, dipolar hyperfine coupling parameter and Fermi contact interaction parameter have been calculated. It is observed that the resultant resonance spectra contain hyperfine structures (hfs) due to V4+ ions which exist as VO2+ ions in octahedral coordination with a tetragonal compression in the present glasses. The tetragonality of V4+O6 complex decreases with increasing concentration of Nb2O5. The 3dxy orbit contracts with increase in Nb2O5:M2O ratio. Values of the theoretical optical basicity, Λth, have also been reported. 相似文献
903.
An efficient synthesis of (+)- and (−)-deoxoprosophylline was accomplished from the readily available cis-2-butene-1,4-diol in which the Sharpless asymmetric dihydroxylation was used as the key step. 相似文献
904.
T. N. Srivastava A. K. S. Chauhan Miss Manjula Agarwal 《Transition Metal Chemistry》1978,3(1):378-379
Summary Binuclear complexes of phenyltin(IV) chlorides with transition metal chelates of tetradentate Schiff bases derived from acetylacetone, benzoylacetone oro-hydroxyacetophenone and ethylenediamine or propylenediamine, of the general formula PhnSnCl4-nML (where n = 1 or 2, M = Ni11 or Cu11 and L2–= the Schiff base dianion), have been synthesised and characterized through elemental analysis, conductance and i.r. spectroscopic data. The coordination of metal chelates to tin involves two triply bonded oxygen atoms giving rise to an octahedral environment around SnIV. The molar conductance of the complexes in nitrobenzene shows the presence of the uncoordinated ML and phenyltin(IV) chloride moieties in solution.Author to whom all correspondence should be directed. 相似文献
905.
Kusuma Kumari Garikapati Ravi Kiran Ammu V. V. V. Praveen Thaggikuppe Krishnamurthy Narenderan S. T. Babu B. Krishnaveni Nagappan 《Biomedical chromatography : BMC》2022,36(5):e5326
A bioanalytical method for the quantification of rosiglitazone in rat plasma and tissues (adipose tissue, heart, brain, bone, and kidney) using LC–MS/MS was developed and validated. Chromatographic separation was achieved on a Gemini C18 column (50 × 4.6 mm, 3 μm) using a mobile phase consisting of 10 mM ammonium formate (pH 4.0) and acetonitrile (10:90, v/v) at a flow rate of 0.8 mL/min and injection volume of 10 μL (internal standard: pioglitazone). LC–MS detection was performed with multiple reaction monitoring mode using target ions at m/z → 358.0 and m/z → 357.67 for rosiglitazone and pioglitazone (internal standard), respectively. The calibration curve showed a good correlation coefficient (r2) over the concentration range of 1–10,000 ng/mL. The mean percentage recoveries of rosiglitazone were found to be over the range of 92.54–96.64%, with detection and lower quantification limit of 0.6 and 1.0 ng/mL, respectively. The developed method was validated per U.S. Food and Drug Administration guidelines and successfully utilized to measure rosiglitazone in plasma and tissue samples. Further, the developed method can be utilized for validating specific organ-targeting delivery systems of rosiglitazone in addition to conventional dosage forms. 相似文献
906.
Mohan Pasham Sharath Babu Haridasyam N. V. V. D. Praveen Boppy Muvvala Venkatanarayana Ashok Kumar Palakurthi 《Biomedical chromatography : BMC》2022,36(4):e5330
Montelukast sodium (MLS) is a leukotriene receptor antagonist drug used in the treatment of asthma, bronchospasm, allergic rhinitis and urticaria. A reversed-phase high performance liquid chromatography method was developed to separate, identify and quantitative determination of MLS and its eight known organic impurities in tablet dosage form using a C18 column and mobile phases consisting of a gradient mixture of pH 2.5 phosphate buffer and acetonitrile. The stability-indicating character of the developed method was proven using stress testing (1 m HCl at 80°C/30 min, 1 m NaOH at 80°C/30 min, H2O at 80°C/30 min, 3% H2O2 at 25°C/1 min, dry heat at 105°C/10 h and UV–vis light/4 days) and was validated for specificity, quantitation limit, linearity, precision, accuracy and robustness. For MLS and its eight known impurities, the quantitation limits, linearity and recoveries were 0.015–0.03 μg/ml, correlation coefficient > 0.997 (R2 > 0.995) and 85.5–107.0%, respectively. The developed chromatographic method is suitable for impurity profiling and also for assay determination of MLS in bulk drugs and pharmaceutical formulations. The mass values (m/z) of newly formed degradation products (DP1 and DP2) of montelukast sodium were identified using liquid chromatography–mass spectrometry. 相似文献
907.
Alassad Mustafa Hussain Muhammad Nihal Agarwal Nitin 《Central European Journal of Operations Research》2022,30(1):367-394
Central European Journal of Operations Research - With the power of social media being harnessed to coordinate events and revolutions across the globe, it is important to identify the key sets of... 相似文献
908.
Madhusudhan C. K. Kumar R. S. Praveen Faisal Muhammad Mahendra K. Raghavendra Narasimha Vasantha V. T. 《Colloid Journal》2022,84(3):364-373
Colloid Journal - The present study highlights the suitability of multiwalled carbon nanotube (MWCNT) incorporated polypyrrole (PPy) nanohybrids for corrosion inhibition applications. These... 相似文献
909.
910.
The laser cooling of atoms is a result of the combined effect of Doppler shift, light shift and polarization gradient. These are the phenomena which generally introduce frequency shift and uncertainty. However, they combine gainfully in realizing laser cooling and trapping of the atoms. In this paper we discuss the laser cooling of atoms in the presence of the squeezed light with the decay of atomic dipole moment into noisy quadrature. We show that the higher decay rate of the atomic dipole moment into the noisy quadrature, which leads to decrease in the signal to noise ratio, may contribute in realizing larger cooling force vis-à-vis with coherent laser light. 相似文献