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91.
Riaz N Anis I Malik A Ahmed Z Aziz-ur-rehman Muhammad P Nawaz SA Choudhary MI 《Chemical & pharmaceutical bulletin》2003,51(3):252-254
Paeonins A and B, new monoterpene galactosides have been isolated from the chloroform-soluble fraction of the roots of Paeonia emodi and showed potent lipoxygenase inhibitory activity. The structures of 1 and 2 have been assigned on the basis of spectral analysis including one- and two-dimensional NMR techniques. 相似文献
92.
93.
The Rayleigh–Taylor instability (RTI) of a ferrofluid has been the subject of recent research, because of its implications on the stability of stellar and planetary interiors. This paper analyzes the effects of rotation and magnetic field on nonlinear RTI of two superposed ferrofluids. It is considered that the system is subjected to uniform parallel rotation and normal magnetic field. Surface tension acts at the interface. The method of multiple scales is utilized to obtain the solutions and dispersion relations are obtained for the nonlinear problem of RTI of magnetic fluids. Finally the stability of the problem is discussed. 相似文献
94.
Afaq Shagufta Khan Sadia Kazmi Mehdi Hassan Fatima Itrat Malik Abdul Inamullah Farah Farhad Zahid Abbas Tanveer Tareen Rasool Bakhsh 《Chemistry of Natural Compounds》2021,57(2):269-273
Chemistry of Natural Compounds - Armatans A (1) and B (2), new isoflavans, have been isolated from the EtOAc-soluble fraction of the MeOH extract of Colutea armata Hemsl. & Lace, along with... 相似文献
95.
An algorithm has been developed for calculating radii, direction vectors, and coordination numbers (c.n.) for an arbitrary number of coordination spheres (CS) of the diamond lattice. It is established that the space of CS of the diamond lattice has imaginary CS in addition to real ones. The imaginary CS are defined by a direction vector, one of the components of which is an imaginary value. The coordination numbers of such CS are zero. For a great number of tabulated CS, we have studied the hierarchies of structural groups (motifs), forming in the space of coordination spheres and determining the X-ray spectra of lattice CS, the crystallomorphological growth forms of diamond crystals, and the forms of diamond fragmentation induced by thermal destruction and melting. 相似文献
96.
Priya Budhani Sayed Aftab Iqbal Suman Malik Mamta Bhattacharya Liviu Mitu 《Journal of Saudi Chemical Society》2010,14(3):281-285
The present paper deals with the synthesis and characterization of Schiff base complexes of pyrazinamide an antitubercular drug. Metals selected for complexation are copper, silver, gold, zinc, mercury, iron and cobalt. The complexes have been suitably synthesized and isolated in pure powdered form. Analytical data agrees with the compositions M(L), M′(L)2 and M″(L)2·2H2O, respectively where M = Ag, M′ = Cu, Au, Zn and Hg and M″ = Fe and Co, ligand metal ratios were also confirmed by monovariation method and Job’s method of continuous variation. Molar conductance values suggest the non ionic nature of the complexes. The tentative structure assigned to the complexes on the basis of stoichiometry and analytical data were further supported by spectral studies viz; IR, NMR, magnetic susceptibility and electronic spectra. A preliminary attempt has also been made to compare the potencies of metal complexes with parent drug. The Cu and Ag complexes are giving encouraging results. Particle size studies further suggest that the drug molecule undergoes reduction in size on complexation. 相似文献
97.
98.
A variety of phosphorodiamidate compounds were synthesized from the corresponding phosphorodichloridate intermediates and phosphorus oxychloride. These were completely characterized using different spectroscopic methods and single crystal X-ray diffraction studies on one of them. Studies revealed that water in the presence of a mild Lewis acid like ZnCl2 was found to assist the hydrolysis of the P–N linkage. The proof of this concept was effectively realized through the hydrolysis of hexamethylphosphoramide. 相似文献
99.
Neha Sharma Bipin K. Srivastava Anjali Krishnamurthy A.K. Nigam 《Solid State Sciences》2010,12(8):1464-1468
Magnetic behaviour of the perovskite La0.5Gd0.5CrO3 has been studied. The orthochromite orders canted antiferromagnetically below Neel temperature TN of ~225 K. Reversal of magnetization is observed in temperature dependence of magnetization measured in field cooled mode under external fields upto 500 Oe. In the field dependence of magnetization below TN, a small hysteresis is observed with the magnetic anisotropy continuously increasing with lowering of temperature. Estimated values of Cr3+ moments, internal field due to sub-lattice of canted ordered Cr3+ and the paramagnetic Curie temperature of Gd3+ sub-lattice are found to be smaller than reported for GdCrO3. Compared with Pr substituted analogue La0.5Pr0.5CrO3, Cr3+ moment is about the same but the internal field at the Gd3+ sub-lattice is much smaller. 相似文献
100.