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111.
A. B. Deshpande C. R. Rajan S. L. Kapur 《Journal of polymer science. Part A, Polymer chemistry》1973,11(6):1317-1320
Vanadium-based catalyst complexes prepared in the presence of monomers have been used for the copolymerization of styrene and acrylonitrile. VOCl3–Al(i-C4H9)3 catalyst system seems to yield an alternating copolymer. The copolymers are easily soluble in DMF and have low softening points. 相似文献
112.
Chemoselective hydrogenation of substituted nitroaromatics using novel water-soluble iron complex catalysts 总被引:2,自引:0,他引:2
Deshpande RM Mahajan AN Diwakar MM Ozarde PS Chaudhari RV 《The Journal of organic chemistry》2004,69(14):4835-4838
Chemoselective hydrogenation of substituted nitroaromatic compounds by water-soluble iron complex catalysts with molecular hydrogen has been reported for the first time. This biphasic catalyst presents an opportunity for a solvent-free hydrogenation. This catalyst system provides a low-cost, efficient alternative to the selective but environmentally unacceptable stoichiometric reductions as well as the supported noble metal catalysts used for hydrogenation. An efficient recycling strategy has resulted in a cumulative turnover number above 6000. 相似文献
113.
A. B. Deshpande S. M. Kale S. L. Kapur 《Journal of polymer science. Part A, Polymer chemistry》1973,11(9):2105-2109
Styrene is polymerized with chromium acetylacetonate–triisobutylaluminum catalyst at 40°C in a benzene medium. At the stoichiometric ratio of Al/Cr of 4, the activity for polymerization was found to be maximum. Further, the kinetic studies were carried out at this ratio of Al/Cr of maximum activity. The kinetics of polymerization and the total activation energy around 10.00 kcal/mole suggest a coordinate anionic mechanism. 相似文献
114.
A study of theEXAFS associated with theK x-ray absorption discontinuity of germanium in pure germanium and in the rare-earth germanides RGe2 (where R=La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er and Y) has been carried out. The Ge-Ge distances have been obtained in these
compounds. Considering the phase to the RGe2 system, the bond lengths in these compounds have been determined. The values obtained by us for the RGe2 compounds (R=La, Ce, Pr, Nd, Sm, Gd, Dy and Y) agree with those obtained earlier by crystallographic methods. The bond lengths
for the compounds TbGe2, HoGe2 and ErGe2 are also being reported. 相似文献
115.
116.
Farheen N. Sayed Srungarpu N. Achary Sudhanshu·K. Deshpande Balasubhramanian Rajeswari Ramakant M. Kadam Sandhya Dwebedi Arun K. Nigam Avesh K. Tyagi 《无机化学与普通化学杂志》2014,640(10):1907-1921
Polycrystalline samples of La2MMnO6 (M = Co and Mg) were prepared by a combined gel‐combustion and high temperature reaction method. The samples were annealed in different oxygen partial pressure (pO2) and characterized by powder XRD, SQUID magnetometry, ac impedance spectroscopy, and electron paramagnetic resonance techniques. Monoclinic (P21/n) and rhombohedral (R$\bar{3}$ ) lattices were observed for La2CoMnO6 and La2MgMnO6, respectively. On annealing in inert atmosphere, La2MgMnO6 partially converted to monoclinic La2CoMnO6 type structure, whereas no structural change was observed in La2CoMnO6. Dielectric studies of La2CoMnO6 indicated relaxor like behavior with polaronic conduction, which systematically decreased with the increase in pO2 of the annealing atmosphere. Magnetic studies indicated multiple ferromagnetic phase transitions in La2CoMnO6 and a spin‐glass like phase transition in La2MgMnO6. The fraction of ferromagnetic phases of La2CoMnO6 was significantly dependent on the annealing environments. The variations of magnetic and dielectric properties of samples were related to the fluctuation of oxidation state of transition metal ions and oxygen vacancies in the samples. 相似文献
117.
M. D. Deshpande Ravindra Pandey Miguel A. Blanco Arun Khalkar 《Journal of nanoparticle research》2010,12(4):1129-1136
We report the magnetic properties of small Ni13-nAln\hbox{Ni}_{13-n}\hbox{Al}_n clusters with n = 0–13 calculated in the framework of density functional theory. The cluster magnetic moment decreases with the sequential
substitution of Ni by Al atoms, which can be attributed to a greater degree of hybridization that forces the pairing of the
electrons in the molecular orbitals of Ni and Al. For Ni7Al6, the complete quenching of the cluster magnetic moment appears to be due to the antiferromagnetic alignment of atomic spins
as revealed by the spin density plots. 相似文献
118.
A. B. Thomas A. A. Chaudhari R. K. Nanda L. P. Kothapalli U. B. Chavan A. D. Deshpande 《Chromatographia》2009,69(11-12):1485-1487
The simultaneous determination of enalapril (Ena) and losartan (Los) in solid dosage forms were done by two methods. The first method involves spectrophotometric determination using the simultaneous equation method at 222 and 250 nm for Ena and Los, respectively. The second method involved an RP-LC method of analysis using methanol:water:acetonitrile (45:35:20% v/v) as the mobile phase. Both methods were satisfactorily validated as per ICH guidelines. 相似文献
119.
Couplings between standard model particles and unparticles from a nontrivial scale invariant sector can lead to long range forces. If the forces couple to quantities such as baryon or lepton (electron) number, stringent limits result from tests of the gravitational inverse square law. These limits are much stronger than from collider phenomenology and astrophysics. 相似文献
120.
Michael A. Schmidt Kishta KatipallyAntonio Ramirez Omid SoltaniXiaoping Hou Huiping ZhangBang-Chi Chen Xinhua QianRajendra P. Deshpande 《Tetrahedron letters》2012,53(31):3994-3997
Efforts to prepare ethyl 3-phenyl-4-(trifluoromethyl)isoxazole-5-carboxylate (1) by developing a regioselective 1,3-dipolar cycloaddition between phenyl nitrile oxide and various 4,4,4-trifluoromethyl crotonates are described. The substitution at the C2-position of crotonate dipolarophile 4 significantly influenced the regiochemistry and yield of the cycloaddition. Enol and enol ether-based crotonates underwent regioselective cycloadditions with phenyl nitrile oxide to provide 4-trifluoromethyl isoxazoles in good yields. 相似文献