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To investigate the modification effect of the modifier ZnO on boro-tellurite glass, a series of glasses with compositions 50B2O3–(50?x)ZnO–xTeO2 have been prepared by conventional melt quenching technique. Amorphous nature of the samples was confirmed through X-ray diffraction technique. Optical absorption and IR structural studies are carried out on the glass system. The optical absorption studies revealed that the cutoff wavelength increases while optical band gap (Eopt) and Urbach energy decreases with an increase of ZnO content. Refractive index evaluated from Eopt was found to increase with an increase of ZnO content. The compositional dependence of different physical parameters such as density, molar volume, oxygen packing density, optical basicity, have been analyzed and discussed. The IR studies showed that the structure of glass consists of TeO4, TeO3/TeO3+1, BO3, BO4 and ZnO4 units. 相似文献
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Ch. V. Koti Reddy R. Balaji Rao K. Chandra Mouli D. V. Rama Koti Reddy K. B. S. Krishna 《Ionics》2013,19(5):811-822
A series of glass samples, according to the formula (100 ? x) (0.5Li2O ? 0.2Ga2O3 ? 0.3P2O5) + xSeO2 (x?=?0, 2, 4, 6, 8, 10) and 12 mol.%, labeled as LGPS x (x is the mole percent of SeO2), were synthesized through melt quenching technique. All the LGPS x samples were irradiated by a high energy proton (H+) beam of 3 MeV at fluence of 1014, 5 × 1014, and 10 × 1014 ions/cm2. FTIR and Raman spectra indicated that SeO2 acts either as a glass modifier (SeO 3 2? ) or a glass former (SeO 4 2? ), as the dose rate of beam fluence changes. The bulk conductivity of the highest conducting sample LGPS10 irradiated at a beam fluence of 5 × 1014 ions/cm2 was determined as 5.87 × 10?04 S/cm at 303 K. The super curve in the normalized spectra of electrical modulus at different temperatures confirms that the LGPS samples follow the temperature-independent, frequency-dependent relaxation time before and after irradiation. 相似文献
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Gangavaram V.M. Sharma Samala Mallesham Chirutha Chandra Mouli 《Tetrahedron: Asymmetry》2009,20(21):2513-2529
Studies directed toward the synthesis of acremodiol and acremonol resulted in the synthesis of two macrodiolides 1, 1a, and 2 besides 3. The attempted synthesis of 1 and 2 confirmed that the absolute stereochemistry defined in the earlier report is incorrect. Compound 1 was synthesized by RCM-mediated macrocyclization. Attempted synthesis of 2 failed to give good yields in the cyclization, and 1a and 2 were synthesized by the Yamaguchi macrolactonization method. 相似文献
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Devineni Subba Rao Madduri Thirupal Reddy Chamarthi Naga Raju Liu Cong-Qiang Pavuluri Chandra Mouli 《Chemistry of Heterocyclic Compounds》2019,55(3):266-274
Chemistry of Heterocyclic Compounds - 2,5-substituted-6-(4-nitrophenyl)-5H-thiazolo[3,2-a]pyrimidin-7-amines. This method, optimized under microwave conditions, was highly efficient and... 相似文献
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Electron spin resonance studies were carried out on VO2+ in cadmium maleate dihydrate single crystals at 303 K. The spin hamiltonian parameters were evaluated. The results lead us
to conclude that like Cu2+, VO2+ enters the lattice interstitially. 相似文献