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41.
A comparative study of the Chevrel phases Mo6S8, Mo6Se8, PbMo6S8 and Cu1.8Mo6S8 is made by the positron angular correlation technique at room temperature. Electronic properties like the number of conduction electrons per cluster, the density of states at the Fermi level, the electron effective masses and the Fermi velocities are obtained within the framework of the free electron model. The results are discussed in terms of available theoretical and other experimental data. 相似文献
42.
Anamalai K. Samylingam L. Kadirgama K. Samykano M. Najafi G. Ramasamy D. Rahman M. M. 《Journal of Thermal Analysis and Calorimetry》2019,135(2):1533-1544
Journal of Thermal Analysis and Calorimetry - The emphasis of this paper is to evaluate the thermophysical properties of crystalline nanocellulose (CNC)-based nanofluid and the optimized machining... 相似文献
43.
Potassium hydrogen malate monohydrate (PHMM), a semi-organic nonlinear optical material, has been synthesized and single crystals were grown from aqueous solution. Single crystals of PHMM have been grown by slow evaporation of solvent at room temperature up to dimensions of 22 mm×16 mm×14 mm. Single-crystal X-ray diffraction study on grown crystals shows that they belong to monoclinic system and non-centrosymmetry spacegroup Cc. The structural perfection of the grown crystals has been analyzed by high-resolution X-ray diffraction (HRXRD) rocking curve measurements. Fourier transform infrared (FTIR) spectroscopic study was performed for the identification of different modes of functional groups present in the compound. The UV–Vis transmission spectrum has been recorded in the range 200–1100 nm. The thermal stability of the compound has been determined by TG-DTA curves. The dielectric studies were performed. From the microhardness measurements, Vicker's hardness number (Hv), Stiffness constant (C11), fracture toughness (kc), Brittle index (Bi) and yield strength (σy) have been calculated. The Young's modulus was calculated using the Knoop hardness measurement. The SHG relative efficiency of PHMM crystal was found to be 1.2 times higher than that of KDP. 相似文献
44.
C.E. Satheesh Pushpanathan N. Sathish Kumar P. Raghavendra Kumara Ramasamy Karvembu Amar Hosamani M. Nethaji 《应用有机金属化学》2019,33(10)
Two new half‐sandwich Ru (II)(p‐cymene) complexes ( 1 and 2 ) containing dopamine‐based (N, O) Schiff base ligands ( L 1 H and L 2 H ) were synthesized and characterized by FT‐IR, UV–Visible and 1H & 13C NMR spectral techniques, and elemental analyses. The spectroscopic and analytical data revealed monobasic bidentate coordination of the ligands with Ru ion. The molecular structures of L 1 H , L 2 H and 2 were further confirmed by single crystal X‐ray diffraction study. Complexes 1 and 2 have been employed as catalysts in the transfer hydrogenation of ketones using 2‐propanol as a hydrogen source at 85 °C under base‐free condition. Good to the excellent yield of secondary alcohols, gram scale synthesis, and high TON and TOF made this catalytic system interesting. 相似文献
45.
46.
B. Sachin Kumar C. Dhanasekhar A. Venimadhav Sreeram K. Kalpathy S. Anandhan 《Journal of Sol-Gel Science and Technology》2018,85(3):664-676
Poly(chloropropyl-methyl)silsesquioxanes (PCMSQ) were prepared using the base catalyzed sol–gel processing on methyltrimethoxysilane (MTMS) and 3-chloropropyltriethoxysilane (CPTES) with 5:5, 6:4, and 7:3 molar ratios in methanol and water. The PCMSQ with 6:4 molar ratio of MTMS:CPTES, which has the maximum yield, according to the elemental analysis, was chosen and some chlorine atoms of the chloropropyl groups were changed to different amines by refluxing it with ethylenediamine (en), diethylenetriamine (dien), ortho-phenylenediamine (opda), and 2-imidazolidinethion (imt). The amine grafted PCMSQ were then used to support MoO2(acac)2 complex and dien grafted PCMSQ with higher metal content was applied to the epoxidation of cis-cyclooctene with TBHP. The product yields were studied by gas liquid chromatography and the catalytic procedure was optimized for the parameters involved such as the solvent and oxidant. The catalytic activity of this catalyst also was investigated toward epoxidation of some other alkenes. It was also applied to check its reuse ability. 相似文献
47.
R. Prakash K. Srinivasamoorthy S. Gopinath K. Saravanan F. Vinnarasi G. Ponnumani S. Chidambaram P. Anandhan 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):25-36
Submarine groundwater discharge is the fresh groundwater discharge to sea that impacts the coastal regions. Radon (222Rn) isotope has been used to quantify SGD in coleroon river estuary, India. Continuous 222Rn analyses were attempted for 10 days in groundwater and pore water samples at three different locations. 222Rn in groundwater ranges between 35.0 and 222.0 Bq m?3 and in pore water between 14.0 and 150.0 Bq m?3 irrespective of locations. The radon mass balance estimated total SGD rate ranges between 2.37 and 7.47 m days?1. The SGD increases with distance from coast, influenced by tides and hydrological features. 相似文献
48.
Dr. Ramasamy Jayarajan Jayabrata Das Sukdev Bag Rajdip Chowdhury Prof. Dr. Debabrata Maiti 《Angewandte Chemie (International ed. in English)》2018,57(26):7659-7663
Arenes containing conformationally flexible long alkyl chains have been successfully functionalized at the meta‐position. Good to excellent meta selectivity is achieved for systems with up to 20 atoms between the target C?H bond and the coordinating heteroatom of the directing group. The palladium‐catalyzed functionalization reactions include alkylation, cyanation, olefination, and acetoxylation. The meta selectivity is exclusively governed by the design of flexible pyrimidine‐based scaffolds. 相似文献
49.
G. Madhurambal P. Ramasamy P. AnbuSrinivasan M. Suganthi G. Vasudevan S. C. Mojumdar 《Journal of Thermal Analysis and Calorimetry》2008,94(1):45-51
Good quality benzophenone (BP) crystals were grown by solution technique using CHCl3 as solvent by adopting slow evaporation method at room temperature. The grown crystals were subjected to various characterization
studies to analyze its purity and applications. The condensation product 2,4-dinitro phenyl hydrazone of benzophenone (DNPBP)
was prepared by adopting standard procedure. Then mixed crystal of BP and DNPBP was also grown by solution growth. Both the
condensation product and mixed crystals were characterized by UV, FTIR, 1H NMR spectra. Thermal (TG and DTA) studies have proved to be very useful techniques not only to study the thermal properties
of BP, DNPBP and mixed crystal but also to study their purity. Second harmonic generation (SHG) efficiency of the grown crystals
was determined. 相似文献
50.
Sreeram Kalarical Janardhanan Indumathy Ramasamy Balachandran Unni Nair 《Transition Metal Chemistry》2008,33(1):127-131
Natural polymers like chitosan and starch have been employed as templates for the preparation of iron oxide nanoparticles.
The templates offer selective binding sites for Fe(II) under aqueous conditions. Controlled drying and subsequent removal
of the template backbone enables the synthesis of spatially separated iron oxide nanoparticles. The crystalline character
of the iron oxide and near narrow particle size distribution pattern have been confirmed through powder XRD, Photon Correlation
Spectroscopy, and TEM measurements. The crystallite sizes of the particles were found to be 26–35 nm irrespective of the nature
of the template. 相似文献