排序方式: 共有6条查询结果,搜索用时 15 毫秒
1
1.
Kaleb C. Burrage Christopher S. Perreault Eric K. Moss Jeffrey S. Pigott Blake T. Sturtevant Jesse S. Smith 《高压研究》2013,33(3):489-498
ABSTRACTThe isothermal compression of transition metal tantalum (Ta) was studied in a diamond anvil cell by X-ray diffraction utilizing rhenium (Re) and gold (Au) as internal X-ray pressure standards. The Re pressure marker was employed during non-hydrostatic compression to pressures up to 310?GPa while the Au pressure marker was used during quasi-hydrostatic compression in a neon pressure-transmitting medium to 80?GPa. Two ultra-high pressure experiments were conducted on Ta and Re mixtures utilizing focused-ion beam machined toroidal diamond anvils with central flats varying from 8 microns to 16 microns in diameter. The Ta metal was observed to be stable in the body-centered-cubic phase to a volume compression V/V0?=?0.581. The measured equations of state (EOS) of Ta using two different calibrations of the Re pressure marker are compared with the ambient temperature isotherm derived from shock compression data. We provide a detailed analysis of EOS fit parameters for Ta under quasi-hydrostatic and non-hydrostatic conditions. 相似文献
2.
Ammonium metavanadate: A novel catalyst for synthesis of 2-substituted benzimidazole derivatives 总被引:1,自引:0,他引:1
Ammonium metavanadate (10 tool%) was found to be a useful catalyst for the synthesis of various 2-substituted aryl benzimidazoles. It was used as an oxidizing agent for the condensation of o-pbenylenediamine with different substituted aryl aldehydes at room temperature in ethanol. The method was proved to be simple, convenient and the product was isolated with good yields (79-91%). 相似文献
3.
Synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzo[d]imidazoles by the reaction of o-phenylenediamine with substituted aromatic aldehydes in the presence of l-heptanesulfonic acid sodium salt (10 mol%) at room temperature.The reactions were performed in acetonitrile:water (8:2).The method was proved to be eco-friendly,convenient and the products were isolated with good yields (82-90%). 相似文献
4.
Mondal Kanchan Hartman Kaleb Dasgupta Debalina Trifon George Dasari Mallika 《Journal of Sol-Gel Science and Technology》2015,73(1):265-269
Journal of Sol-Gel Science and Technology - 1-D nanostructures are deemed to be important building blocks for future optical and optoelectronic nanodevices. We have used electrospinning methods to... 相似文献
5.
East AL Grittner KL Afzal AI Simpson AG Liebman JF 《The journal of physical chemistry. A》2005,109(50):11424-11428
Conjugated polyynes are a class of species of diverse and increasing interest. Length-scrambling and substituent scrambling reaction energies were examined using ab initio quantum chemistry calculations to investigate issues concerning the energetic effects of the molecular ends (substituent communication). Computations were performed for the parent, monohalogenated, and dihalogenated (F, Cl, Br, I) polyynes of up to 60 carbon atoms. A study of resonance effects using natural resonance theory and bond lengths demonstrates lone-pair-donating effects that increase in the series F < Cl < Br < I, but run counter to the halogen inductive effects which decrease in this series and dominate energetic effects. 相似文献
6.
Francis H. Barnes Aaron D. Nicholas Henry Melzer Kaleb P. Cormier Matthew D. Kessler Howard H. Patterson Robert D. Pike 《无机化学与普通化学杂志》2019,645(16):1043-1051
trans‐[Ln(NO3)2(Ph3AsO)4](NO3)2 ( 1 ) and mer‐[Ln(NO3)3(Ph3AsO)3] ( 2 ) complexes were prepared from Ln(NO3)3 · xH2O and Ph3AsO in chloroform (Ln = Y, Sm, Eu, Tb, and Dy). Production of complexes 1 vs. 2 and solvent content was found to be highly dependent on crystallization solvent choice. Tb and Eu produced only 1 , while the other Ln metals produced both 1 and 2 . Solvent‐free, acetone‐, and methanol‐containing polymorph series were identified for complexes 1 . Acetone/ether‐ and CH2Cl2‐containing polymorph series were identified for complexes 2 . Luminescence measurements were performed on solvent‐free 1 (Ln = Y, Eu, Tb, and Dy) and 2 (Ln = Sm) at 78 K. Sensitized lanthanide emission bands via resonance energy transfer were observed in all cases, except the control (Ln = Y). The efficiency of this energy transfer process varies amongst the lanthanide metals studied and was rationalized using Latva's empirical rule and Density Functional Theory calculations. 相似文献
1