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101.
Vaneet K. Sharma Sonam Bansal Ashok K. Malik † Rakesh K. Mahajan 《International journal of environmental analytical chemistry》2013,93(14-15):1105-1110
A procedure has been developed for the direct fourth derivative spectrophotometric determination of zinc(II) dimethyldithiocarbamate by converting it into its copper(II) dimethyldithiocarbamate complex, which is then dissolved in Triton X-100. Beer's law is obeyed over the concentration range 0.5–30?µg/mL in the final solution. Various parameters such as the effect of pH and the interference of a number of ions on the determination of Ziram have been studied in detail. The method is sensitive and can be used for the determination of Ziram in commercial samples like Zirax and Ziron containing Ziram and from wheat grains. 相似文献
102.
103.
Experimental densities (ρ), viscosities (η), and speeds of sound (u) of the binary mixtures of n-dodecane with an alkan-1-ol (hexan-1-ol, heptan-1-ol, octan-1-ol) or an alkan-2-ol (hexan-2-ol, heptan-2-ol and octan-2-ol) were measured over the whole mixture composition range at T = 298.15 K. From these data, the excess molar volume ( $ V_{\text{m}}^{\text{E}} $ V m E ), deviations in viscosity (Δη), and excess isentropic compressibility ( $ \kappa_{S}^{\text{E}} $ κ S E ) have been calculated. The results were fitted by means of the Redlich–Kister equation, in order to estimate the binary coefficients and standard errors. Differences among these binary systems are ascribed to the different association abilities of the alkan-1-ols and alkan-2-ols. Experimental data on the constituted binaries were analyzed using McAllister’s multi-body interaction model, the Jouyban–Acree model, the Prigogine–Flory–Patterson theory, and the Bloomfield and Dewan model. The experimental and calculated quantities are used to study the nature of mixing behavior among the mixtures. 相似文献
104.
Hitendra S. Mahajan Mayur H. Pingale Kapil M. Agrawal 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(3-4):467-472
The objective of the present study was to formulate inclusion complex of saquinavir mesylate to improve the aqueous solubility and dissolution rate. Saquinavir mesylate is a BCS class II drug having low aqueous solubility and therefore low oral bioavailability. In the present study, inclusion complex of saquinavir mesylate with hydroxypropyl-β-cyclodextrin were prepared by kneading method. Inclusion complex were characterized by differential scanning calorimetry (DSC), X-ray diffractometry (XRD), 1H NMR studies, and Fourier transform infrared spectroscopy and evaluated for in vitro dissolution, and phase solubility studies. DSC and XRD study demonstrated that there was a significant decrease in crystallinity of pure drug present in inclusion complex, which resulted in an increased dissolution rate of saquinavir mesylate and 1H NMR studies strongly, confirmed that the inclusion complex has formed. Inclusion complexation results in improvement in solubility and dissolution rate. The inclusion complexation would be suitable method for dissolution and bioavailability enhancement of saquinavir mesylate. 相似文献
105.
Monika Swami Karuna Mahajan Neeti Gupta R. V. Singh Sunita Arya Sonalika Kushwah 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):2125-2139
The present article describes the synthesis and characterization of tetracoordinated boron (III) complexes with monobasic bidentate ligands (L 1 H, L 2 H, L 3 H, L 4 H, L 5 H, and L 6 H) having the general formulae PhB(L)(OH) and PhB(L) 2 . The 1:1 and 1:2 reactions of phenyl boronic acid with monobasic bidentate ligands resulted in the formation of colored solids. The complexes have been characterized by elemental analysis, molecular weight determinations, and IR and NMR ( 1 H, 13 C and 11 B) spectroscopy, as well as UV-vis spectral studies. Based on these studies, a tetrahedral geometry has been proposed for the resulting complexes. The ligands, along with their complexes, have been screened in vitro against a number of pathogenic fungal and bacterial strains. The studies indicate that the boron chelates are more potent than the parent ligands. 相似文献
106.
Karuna Mahajan Monika Swami R. V. Singh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2664-2679
Tetra- and pentacoordinated antimony and bismuth derivatives have been prepared by the interactions of monophenylantimonydichloride(III), trichlorostibane, and trichlorobismuthane with the sodium salts of 3-(indolin-2-one)hydrazinecarbothioamide (L1H) and 3-(indolin-2-one)hydrazinecarboxamide (L2H), under microwave irradiation as well as by conventional heating. These compounds were further characterized by analytical and spectroscopic techniques including UV, IR, 1H NMR, and 13C NMR spectra. Newly synthesized complexes with their corresponding ligands were also tested for their antifungal and antibacterial activities. 相似文献
107.
Nonlinear Dynamics - We study the 2D dynamics of a rigid dimer, a dumbbell-shaped extended body, on an elastic surface carrying a harmonic traveling wave. The impact of the dimer with the surface... 相似文献
108.
Penicillin acylases 总被引:5,自引:0,他引:5
Pramod B. Mahajan 《Applied biochemistry and biotechnology》1984,9(5-6):537-554
109.
Amol Dighe Anirban Kundu K. Agashe B. Anantanarayan A. Chandra A. Datta P. K. Das S. P. Das A. Dighe R. Forty D. K. Ghosh Y. -Y. Keum A. Kundu N. Mahajan S. Majhi G. Mazumdar K. Mazumdar P. Mehta Y. Nir J. P. Saha R. Singh N. Sinha R. Sinha A. Soni S. Uma Sankar R. Vaidya 《Pramana》2004,63(6):1359-1365
This is a report of the low energy and flavour physics working group at WHEPP-8, held at the Indian Institute of Technology,
Mumbai, India, during 5–16 January 2004. 相似文献
110.
Bhimrao D. Sarwade Sudhakar S. Mahajan 《Journal of polymer science. Part A, Polymer chemistry》1991,29(6):825-829
Polyamides were synthesized from diacids containing a s-triazine ring and two aromatic diamines, namely 4,4′-diaminodiphenyl ether (ODA) and 4,4′-diaminodiphenylmethane (MDA), by direct polycondensation using the phosphorylation reaction. Polymers thus obtained were characterized by viscosity measurement, IR spectroscopy, thermogravimetry, X-ray diffraction, and solubility tests. These polyamides had inherent viscosities in the range of 0.51–0.77 dL/g, and were amorphous in nature. All the polymers were readily soluble in various organic solvents and did not lose weight below 270°C in air. 相似文献