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971.
Hasuike Noriyuki Miyamoto Nobutoshi Funahashi Kohei Takeda Minoru 《Optical Review》2021,28(6):620-625
Optical Review - The correlation between electrical properties and surface plasmon resonance (SPR) wavelength was discussed using ITO grating coupler. ITO films were prepared on SiO $$_{2}$$ /Si... 相似文献
972.
973.
A synthesis of (±)-heliannuol C is described involving Bargellini condensation, Dieckmann cyclization and ortho-ester Claisen rearrangement followed by a regioselective epoxide reduction. A new CuI-catalyzed [2+2] cycloaddition reaction is also described. 相似文献
974.
975.
Kazuto Nagata Nobuhiro Takeda Norihiro Tokitoh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1859-1862
The first stable disulfido and diselenido complexes of platinum-bearing bulky phosphine ligands were synthesized by the reaction of the corresponding zerovalent platinum complexes with elemental sulfur and selenium, respectively. The molecular structures of these complexes were determined by spectral data, elemental analysis, and X-Ray crystallographic analysis. 相似文献
976.
Abstract The Syn isomers (3b and 4b) of xylene-bridged cryptophane showed selective complexing abilities for 2,2-dimethylbutane, 3-methylpentane, 3,3-di-methylpentane and 3-ethylpentane among the investigated alkanes, although the Anti isomers (3a,4a,5a) did not complex with these alkanes. However, both the Anti-and Syn-isomers (2a and 2b) of the diethyleneoxy-bridged cryptophane showed selective complexing abilities for 2,2-dimethylbutane, 3,3-dimethylpentane, 2,2,3-trimethylbutane and 2,2,3,3-terramethybutane among the investigated alkanes. 相似文献
977.
Sen‐Wang Zhang Ling‐Pan Lu Ying‐Yun Long Yue‐Sheng Li 《Journal of polymer science. Part A, Polymer chemistry》2013,51(24):5298-5306
A series of novel vanadium(III) complexes bearing bidentate phenoxy‐phosphine oxide [O,P=O] ligands, (2‐R1‐4‐R2‐6‐Ph2P=O‐C6H2O)VCl2(THF)2 ( 2a : R1 = R2 = H; 2b : R1 = F, R2 = H; 2c : R1 = tBu, R2 = H; 2d : R1 = Ph, R2 = H; 2e : R1 = R2 = Me; 2f : R1 = R2 = tBu; 2g : R1 = R2 = CMe2Ph) have been synthesized by adding 1 equiv of the ligand to VCl3(THF)3 dropwise in the presence of excess triethylamine. Under the same conditions, the adding of VCl3(THF)3 to 2.0 equiv of the ligand afforded vanadium(III) complexes bearing two [O,P=O] ligands ( 3c , 3f ). All the complexes were characterized by FTIR and mass spectra as well as elemental analysis. Structures of complexes 2c and 3c were further confirmed by X‐ray crystallographic analysis. On activation with Et2AlCl and ethyl trichloroacetate, these complexes displayed high catalytic activities for ethylene polymerization (up to 26.4 kg PE/mmolV·h·bar) even at high reaction temperature (70 °C) indicative of high thermal stability, and produced high molecular weight polymers with unimodal molecular weight distributions. Additionally, the complexes with optimized structure exhibited high catalytic activities for ethylene/1‐hexene copolymerization. Catalytic activity, comonomer incorporation, and polymer molecular weight can be controlled in a wide range via the variation of catalyst structure and the reaction parameters such as Al/V molar ratio, comonomer feed concentration, and reaction temperature. The monomer reactivity ratios rE and rH were determined according to 13C NMR spectra, which indicated these complexes preferred ethylene to 1‐hexene in the copolymerization. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 5298–5306 相似文献
978.
Dr. Ting‐Jen R. Cheng Shi‐Yun Wang Dr. Wen‐Hsien Wen Dr. Ching‐Yao Su Mengi Lin Wen‐I Huang Dr. Ming‐Tsan Liu Dr. Ho‐Sheng Wu Nung‐Sen Wang Chung‐Kai Cheng Chun‐Lin Chen Dr. Chien‐Tai Ren Dr. Chung‐Yi Wu Prof. Jim‐Min Fang Dr. Yih‐Shyun E. Cheng Prof. Chi‐Huey Wong 《Angewandte Chemie (International ed. in English)》2013,52(1):366-370
979.
980.
We construct a BCS-like model that combines nucleonic pairing correlations and possible quartic correlations of alpha-type
in a single variational wave function and derive corresponding gap equations. In the approximation of large logarithms typical
for the BCS approach, we show that the system reveals two possible types of a condensate which cannot coexist. If the alpha-type
condensate prevails at N = Z, the growth of the neutron excess will naturally lead to the first order phase transition to the nucleon condensates. 相似文献