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61.
Garg BS Nandan Kumar D Sarbhai M Reddy MJ 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(12):2775-2783
Dimeric (hydrated and anhydrated) complexes of Cu(II) with N,N'-bis(3-carboxy-1-oxo-2-prop-2-enyl)ethylenediamine(BCOPENH(2), A) and N,N'-bis(2-carboxy-1-oxo-phenylenyl)ethylenediamine(BCOPHENH(2), B) have been prepared and characterised by elemental analysis, magnetic susceptibility measurements, EPR, thermal and spectral (IR, UV/Vis) studies. EPR parameters and magnetic behaviour indicates that the complexes are antiferromagnetic in nature and most likely adopt the typical carboxylate cage structure. Interesting amide bonding patterns have been observed and various EPR parameters have been evaluated on the basis of these studies, tentative probable structures of the complexes have been proposed. 相似文献
62.
We study chiral symmetry structure at finite density and temperature in the presence of external magnetic field and gravity,
a situation relevant in the early Universe and in the core of compact stars. We then investigate the dynamical evolution of
phase transition in the expanding early Universe and possible formation of quark nuggets and their survival. 相似文献
63.
64.
A linear ball is a simplicial complex whose geometric realization is homeomorphic to a ball and whose Stanley–Reisner ring has a linear resolution. It turns out that the Stanley–Reisner ring of the sphere which is the boundary complex of a linear ball satisfies the multiplicity conjecture. A class of shellable spheres arising naturally from commutative algebra whose Stanley–Reisner rings satisfy the multiplicity conjecture will be presented. 相似文献
65.
Harsh Kumar Meenu Singla Rajeev Jindal 《Monatshefte für Chemie / Chemical Monthly》2014,145(4):565-575
66.
One of the most powerful rare earth oxides, ceria CeO2 was incorporated in Ni matrix and the effect of cobalt addition in the matrix, on the structure and properties has been studied. The amount of cobalt incorporated in the Ni matrix was in the range of 25-85 wt.%. The presence of cobalt resulted in a marginal variation in CeO2 content from 5 to 8 wt.%. The microhardness studies revealed that a maximum value of 540 Hk50gf was obtained in the presence of 25 wt.% cobalt in Ni-CeO2 matrix compared to 50 and 85 wt.% addition. The presence of 25 wt.% cobalt in Ni-CeO2 matrix also improved its wear resistance as seen from Tribology studies. The wear products were identified using Raman Spectroscopy. The X-ray diffraction (XRD) studies showed that an increase in cobalt content from 25 to 85 wt.% resulted in a change in crystal structure from fcc to hcp. A change in surface morphology with variation in cobalt content was seen from scanning electron microscopy (SEM). It was perceived from the thermal stability studies that the presence of 85 wt.% cobalt in Ni-CeO2 matrix imparted better stability in microhardness at temperatures up to 800 °C. Although, the incorporation of cobalt in Ni-CeO2 matrix enhanced the microhardness, wear resistance and thermal stability it did not improve the corrosion resistance as noticed from immersion corrosion studies. 相似文献
67.
Bi4−xMxV2O11 (M = La, Gd) was prepared by solid state reactions. The amount of La and Gd in the (Bi4−xMxV2O11) was varied in the range of (0 x 0.4). The addition of La and Gd to Bi4V2O11 electrolyte was found to stabilize the β crystalline phase for x 0.3. In addition, the phase transition corresponding β- to γ-phases are evident in the ionic conductivity plots as well as in XRD, DSC profiles of x 0.3 samples. The highest ionic conductivity was observed in Bi3.9La0.1V2O11 and Bi3.8Gd0.2V2O11 samples in the range of 10−3–10−4 S/cm for 700–500 °C. These results were supported by impedance spectroscopy, X-ray diffraction (XRD) and differential scanning calorimetry (DSC). 相似文献
68.
In recent decades, a large number of reports related to the synthesis of N-, O- and S-containing heterocycles have appeared owing to a wide variety of their biological activity. The investigation of methods for the chemical synthesis is a growing area of interest due to increasing environmental issues. The use of catalysts in organic reactions has gained extensive interest. Metal and nonmetal catalysts provided a new improved alternative to traditional methods in modern synthetic chemistry. The aim of present review is to focus on the applications of nickel for the synthesis of five-membered heterocylces. 相似文献
69.
70.
Dharam V.S. Jain Vijay K. Singla Suraj B. Saini Rajwant S. Sidhu 《The Journal of chemical thermodynamics》1983,15(12):1105-1107
Excess molar volumes VmE as function of mole fraction x for methylcyclohexane + benzene, + methylbenzene, + 1,4-dioxane, and + tetrahydrofuran are reported at 303.15 K. The excess molar volumes are positive and indicate the presence of weak interactions. 相似文献