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51.
Naomichi Furukawa Mitsuo Fukumura Takehiko Nishio Shigeru Oae 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):231-237
Abstract Various N-acyldiphenylsulfilimines (1a-k) were found to undergo photolysis in argon atmosphere, to afford the corresponding isocyanates, diphenyl sulfide and diphenyl disulfide. Attempts to trap intramolecularly the acylnitrene with olefinic linkage or sulfide afforded small amounts of the trapped products, whereas photolysis of N-mesitoyldiphenyl-sulfilimine (Ia) afforded a C–H inserted product of the nitrene in a substantial yield together with the isocyanate. Benzophenone-sensitized photolysis of Ia indicates that the nitrene generated is a singlet species. 相似文献
52.
Norimasa Yoza Hisanobu Hirano Yoshinobu Baba Shigeru Ohashi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):605-608
Abstract Inorganic pyrophosphatase (EC 3. 6. 1. 1) drived the reaction of uridine 5′-triphosphate with glucose 1-monophosphate in the direction of uridine 5′-diphosphoglucose formation. 相似文献
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54.
Unmodified and SiCl4-modified spherical zirconia-supported methylaluminoxane were used as cocatalyst for propylene polymerization as well as ethylene/1-hexene copolymerization in combined with Me2Si(η3-C13H8)(η1-NtBu)TiMe2 (1) at 0 °C. The modification with SiCl4 improved the catalytic activity. The improvement was clearer in ethylene/1-hexene copolymerization than in propylene polymerization. The number average molecular weight (Mn) of polypropylenes increased linearly against the polymerization time regardless the cocatalyst used to give polymers with narrow molecular weight distribution (Mw/Mn < 1.32), indicating the living nature of the catalytic systems. Thus, propagation rate constant (kp) and the number of active centers (C*) were evaluated from Mn and the number of polymer-chains. When the zirconia was modified with SiCl4, the kp value decreased and the C* increased. The latter effect was more significant to enhance the catalytic activity. 相似文献
55.
Tao Yang Prof. Dr. Xiang Zhao Prof. Dr. Shigeru Nagase 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(8):2649-2654
Like C60, C70 is one of the most representative fullerenes in fullerene science. Even though there are 8149 C70 isomers, only two of them have been found before: the conventional D5h and an isolated pentagon rule (IPR)‐violating C2v(7854). Through the use of quantum chemical methods, we report a new unconventional C70 isomer, C2(7892), which survives in the form of dimetallic sulfide endohedral fullerene Sc2S@C70. Compared with the IPR‐obeying C70 and the C2v(7854) fullerene with three pairs of pentagon adjacencies, the C2(7892) cage violates the isolated pentagon rule and has two pairs of pentagon adjacencies. In Sc2S@C2(7892)‐C70, two scandium atoms coordinate with two pentalene motifs, respectively, presenting two equivalent Sc? S bonds. The strong coordination interaction, along with the electron transfer from the Sc2S cluster to the fullerene cage, results in the stabilization of the non‐IPR endohedral fullerene. The electronic structure of Sc2S@C70 can be formally described as [Sc2S]4+@[C70]4?; however, a substantial overlap between the metallic orbitals and cage orbitals has also been found. Electrochemical properties and electronic absorption, infrared, and 13C NMR spectra of Sc2S@C70 have been calculated theoretically. 相似文献
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Tomohito Morosaki Tsubasa Suzuki Wei‐Wei Wang Shigeru Nagase Takayoshi Fujii 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(36):9723-9725
Electronic effects on the central carbon atom of carbone, generated by the replacement of the SIV ligand of carbodisulfane (CDS) with other chalcogen ligands (Ph2E, E=S or Se), were investigated. The carbones Ph2E→C←SPh2(NMe) [E=S( 1 ) or Se( 2 )] were synthesized from the corresponding salts, and their molecular structures and electronic properties were characterized. The carbone 2 is the first carbone containing selenium as the coordinated atom. DFT calculations revealed the electronic structures of 1 and 2 , which have two lone pairs of electrons at the carbon center. The trend in HOMO energy levels, estimated by cyclic voltammetry measurements, for the carbones and CDS follows the order of 2 > 1 >CDS. Analysis of a doubly protonated dication and trication complex revealed that the central carbon atom of 2 behaves as a four‐electron donor. 相似文献
58.
The electrical conductivity in aqueous solutions of electrolytes has been obtained in terms of inter-particle potentials and pair distribution functions, based on a generalized Langevin equation for the cation and anion. This treatment allows us to connect and compare with the work of a computer simulation where the inter-particle potentials are the only input. The results for the concentration dependence of electrical conductivity are basically represented as a function of the square root of concentration. The electrophoretic and relaxation effects are discussed from a microscopic view point. The ionic hydration in electrolytic solution is also discussed. Available inter-particle potentials in aqueous solutions of electrolytes are proposed. The numerical application is carried out for sodium chloride and other aqueous electrolyte solutions. 相似文献
59.
WeiPing Liu ZhiHong Li JiangJun He XiaoDong Tang Gang Lian Zhu An JianJun Chang Han Chen QingHao Chen XiongJun Chen ZhiJun Chen BaoQun Cui XianChao Du ChangBo Fu Lin Gan Bing Guo GuoZhu He Alexander Heger SuQing Hou HanXiong Huang Ning Huang BaoLu Jia LiYang Jiang Shigeru Kubono JianMin Li KuoAng Li Tao Li YunJu Li Maria Lugaro XiaoBing Luo HongYi Ma ShaoBo Ma DongMing Mei YongZhong Qian JiuChang Qin Jie Ren YangPing Shen Jun Su LiangTing Sun WanPeng Tan Isao Tanihata Shuo Wang Peng Wang YouBao Wang Qi Wu ShiWei Xu ShengQuan Yan LiTao Yang Yao Yang XiangQing Yu Qian Yue Sheng Zeng HuanYu Zhang Hui Zhang LiYong Zhang NingTao Zhang QiWei Zhang Tao Zhang XiaoPeng Zhang XueZhen Zhang ZiMing Zhang Wei Zhao Zuo Zhao Chao Zhou JUNA Collaboration 《中国科学:物理学 力学 天文学(英文版)》2016,59(4):642001
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of~(25)Mg(p,γ)~(26)Al,~(19)F(p,α)~(16)O,~(13)C(α,n)~(16)O and ~(12)C(α,γ)~(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given. 相似文献
60.
JianJun He ShiWei Xu ShaoBo Ma Jun Hu LiYong Zhang ChangBo Fu NingTao Zhang Gang Lian Jun Su YunJu Li ShengQuan Yan YangPing Shen SuQing Hou BaoLu Jia Tao Zhang XiaoPeng Zhang Bing Guo Shigeru Kubono WeiPing Liu 《中国科学:物理学 力学 天文学(英文版)》2016,59(5):652001
In 2014, the National Natural Science Foundation of China(NSFC) approved the Jinping Underground Nuclear Astrophysics laboratory(JUNA) project, which aims at direct cross-section measurements of four key stellar nuclear reactions right down to the Gamow windows. In order to solve the observed fluorine overabundances in Asymptotic Giant Branch(AGB) stars, measuring the key ~(19)F( p,α)~(16)O reaction at effective burning energies(i.e., at Gamow window) is established as one of the scientific research sub-projects. The present paper describes this sub-project in details, including motivation, status, experimental setup, yield and background estimation, aboveground test, as well as other relevant reactions. 相似文献