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排序方式: 共有452条查询结果,搜索用时 15 毫秒
1.
Giannatiempo A. Nannini A. Perego A. Sona P. 《The European Physical Journal A - Hadrons and Nuclei》2002,13(3):339-347
The states of 104Pd, populated in the EC-β+ decay of the ground ( J π = 5+) and metastable ( J π = 2+) states of 104Ag, have been investigated in the framework of the proton-neutron interacting boson model, extending a previous analysis to take into account the newly appeared experimental data. All positive-parity states up to an excitation energy of 3 MeV and spin in the range J = 1-6, fed by more than 0.3% in the decay of the parent nucleus, have been considered. As a result, strong evidence has been found for interpreting most of these states as states of collective nature having a quite pure full- or mixed-symmetry character and, in particular, for identifying the 1+ level at 2276 keV as the lowest 1+ mixed-symmetry state. 相似文献
2.
Kelly A. Burke Sona Sivakova Blayne M. McKenzie Patrick T. Mather Stuart J. Rowan 《Journal of polymer science. Part A, Polymer chemistry》2006,44(17):5049-5059
We report herein studies on the liquid crystalline behavior of a series of supramolecular materials that contain different ratios of two complementary symmetrically-substituted alkoxy-bis(phenylethynyl)benzene AA- and BB-type monomers. One monomer has thymine units placed at either end of the rigid mesogenic core, while the other has N6-(4-methoxybenzoyl)-adenine units placed on the ends. Differential scanning calorimetric and polarized optical microscopy studies have been carried out on these systems. These studies show that the material's behavior is strongly dependent on its thermal history. As a result, the materials can exhibit, on heating, either a liquid crystalline phase, a crystalline phase, or the coexistence of crystalline and liquid crystalline regions. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5049–5059, 2006 相似文献
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The inhibition of the model enzyme, haloalkane dehalogenase from Sphingomonas paucimobilis, was investigated by a combination of electrophoretically mediated microanalysis with a partial filling technique, followed by indirect or direct detection. In this setup, part of the capillary is filled with a buffer suitable for the enzymatic reaction (20 mM glycine buffer, pH 8.6) whereas the rest of the capillary is filled with the background electrolyte optimal for separation of substrates and products. Two different background electrolytes and corresponding detection approaches were used to show the versatility of the developed method. The inhibition effect of 1,2-dichloroethane on the dehalogenation of brominated substrate 1-bromobutane was studied by means of 10 mM chromate - 0.1 mM cetyltrimethylammonium bromide (pH 9.2) in combination with indirect detection or 20 mM beta-alanine - hydrochloric acid (pH 3.5) in combination with direct detection. The method was used to estimate the inhibition constant K(I) (0.44 mM by indirect detection and 0.63 mM by of direct detection) and to determine the inhibition type. Compared to spectrophotometric and other discontinuous assays, the method is rapid, can be automated, and requires only small amount of reagents that is especially important in the case of enzymes and inhibitors. 相似文献
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Issa Yavari Loghman Moradi Farough Nasiri Hoorieh Djahaniani 《Monatshefte für Chemie / Chemical Monthly》2005,36(9):1757-1761
The regioselective reaction of N1-benzyl-N2-(4-nitrophenyl)ethanediamide with dialkyl acetylenedicarboxylates or alkyl propiolates in the presence of triphenylphosphine
leads to dialkyl 4-benzylamino-1-(4-nitrophenyl)-5-oxo-2,5-dihydro-1H-pyrrole-2,3-dicarboxylates or alkyl 4-benzylamino-1-(4-nitrophenyl)-2-oxo-5-pyrrolidinecarboxylates in good yields. 相似文献
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Mwsleh Mwhmadi Mehdi Kamali Jamal Rashidiani Omid Rezai Kaveh Moradi Ashkan Faridi Khadijeh Eskandari 《Journal of Cluster Science》2014,25(6):1577-1587
NiO and CuO nanostructures were synthesized successfully via simple and fast microwave approach. Olive oil was chose as surfactant for stabilizing nanostructures. Different parameters such as microwave time and power and olive oil concentration were investigated on product size and morphology. The products were characterized with X-ray diffraction pattern, scanning electron microscopy, transmission electron microscopy and energy dispersive spectrometry analysis. 相似文献