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71.
72.
A green synthesis of 1,2,3-triazolyl-pyridine hybrids and evaluation of their antibacterial activity
73.
Sivaperuman Saravanan Shanmugam Muthusubramanian 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2411-2421
Synthesis and characterization of several diethyl 2-[aryl(4-aryl-1,2,3-selenadiazol-5-yl)methyl]malonates are reported. 相似文献
74.
Tidmarsh IS Laye RH Brearley PR Shanmugam M Sañudo EC Sorace L Caneschi A McInnes EJ 《Chemical communications (Cambridge, England)》2006,(24):2560-2562
The solvothermal synthesis, crystal structure and preliminary magnetic studies are reported of the first high nuclearity V(III)-based polyoxo(alkoxo)vanadium cage, a V(III)16V(IV)2 complex. 相似文献
75.
We present a simple and facile synthesis of MnO octahedral nanocrystals and MnO@C core-shell composite nanoparticles. The synthesis is accomplished by a single-step direct pyrolysis of cetyltrimethylammonium permanganate in specially made Let-lock union cells. The products are characterized by HRSEM, HRTEM, Raman spectroscopy, and cyclic voltammetry (CV). The product consists mainly of octahedral MnO nanocrystals and MnO coated with carbon (MnO@C). The core-shell particles are observed only when the core size is smaller than 150 nm. The shape of the nanocrystals can be controlled by varying parameters such as reaction temperature and duration. As the temperature increases from 600 to 800 degrees C, the octahedral MnO crystals observed are without any carbon shell. The effect of time and temperature on the octahedral MnO nanocrystal formation is described. The electrocatalytic activities of the products are studied for oxygen reduction reaction in aqueous basic medium and are compared with bulk MnO. The MnO nanocrystals and core-shell composites exhibit higher activity than that of bulk MnO. 相似文献
76.
Ikeda S Toganoh M Easwaramoorthi S Lim JM Kim D Furuta H 《The Journal of organic chemistry》2010,75(24):8637-8649
A variety of N-fused porphyrin derivatives were prepared and their photophysical properties were investigated. Although intact N-fused tetraarylporphyrins showed almost no emission, introduction of electron-withdrawing groups such as a nitro group and a cyano group on the macrocycles caused significant refinements in their emission efficiency. Long emission wavelengths (900-1000 nm) as well as fairly large Stokes shifts (~1200 cm(-1)) are exceptionally unique photophysical properties among [18]annulenic compounds, which could be rationalized by the excited state intramolecular proton transfer (ESIPT) process. Relatively weak emission quantum yields (~5.0 × 10(-4)) and unusually short S(1) state lifetimes (~13.5 ps) are in good agreement with the ESIPT process. The solvent and substituent effects on the photophysical properties are also discussed in conjunction with the theoretical studies, where the mesityl groups at the meso-positions play a unique role. 相似文献
77.
A new superionic conducting transparent phosphate glasses with composition Li(4+x)TixNb1?xP3O12 (0 ≤ x ≤ 1.0) were prepared by rapid melt quenching. As quenched samples were characterized by X-ray powder diffraction, differential scanning calorimetric and Fourier transform infrared spectroscopy studies. These glasses were found to have high thermal stability parameter and Li4NbP3O12 has been found to have high glass forming ability. Electrical properties of the present glasses were studied by impedance and dielectric spectroscopy in the frequency range 10 Hz–3 MHz in the temperature range 323–523 K. Arrhenius behavior has been observed for all the glass in conductivity, dielectric loss and conductivity relaxation and their activation energies are explained and reported. 相似文献
78.
Landau theory used for studying hot rotating nuclei usually uses zero temperature Strutinsky smoothed total energy for the
temperature dependent shell corrections. This is replaced in this work by the temperature dependent Strutinsky smoothed free
energy. Our results show that this replacement has only marginal effect for temperatures greater than 1 MeV but plays significant
role at lower temperatures. 相似文献
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