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101.
Mitsuharu Fujita Yoshitaro Miyashita Nagina Amir Yasunori Yamada Kiyoshi Fujisawa Ken‐ichi Okamoto 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(9):m435-m436
In the complex cation of the title compound, [Ir2(C2H6NS)2(C4H12N2S2)2]Br4·2H2O, which was obtained by rearrangement of [Re{Ir(aet)3}2]3+ (aet is 2‐aminoethanethiolate) in an aqueous solution, two approximately octahedral fac(S)‐[Ir(NH2CH2CH2S)3] units are linked by two coordinated disulfide bonds. The complex cation has a twofold axis, and the two non‐bridging thiolate S atoms in the complex are located on opposite sides of the two disulfide bonds. Considering the absolute configurations of the two octahedral units (Δ and Λ) and the four asymmetric disulfide S atoms (R and S), the complex consists of the ΔRRΔRR and ΛSSΛSS isomers, which combine to form the racemic compound. 相似文献
102.
Wen Hu Dr. Xiao D. Niu Dr. Masaharu Watada Yoshiteru Kawabe Yao M. Wu Prof. Li D. Wang Li M. Wang Prof. 《Chemphyschem》2010,11(1):295-300
The discovery of the icosahedral phase (i‐phase) in rapidly quenched Ti1.6V0.4Ni1?xCox (x=0.02–0.1) alloys is described herein. The i‐phase occurs in a similar amount relative to the coexisting β‐Ti phase. The electron diffraction patterns show the distinct spot anisotropy, indicating that the i‐phase is metastable. The electrochemical hydrogen storage performances of these five alloy electrodes are also reported herein. The hydrogen desorption of nonelectrochemical recombination in the cyclic voltammetric (CV) response exhibits the demand for electrocatalytic activity improvement. A discharge capacity of 261.5 mA h g?1 was measured in a Ti1.6V0.4Ni0.96Co0.04 alloy electrode at 30 mA g?1 and 303 K and it is shown that an appropriate amount of Co element addition would enhance the cycling stability at the expense of high‐rate discharging ability. 相似文献
103.
New Fluorescence Domain “Excited Multimer” Formed upon Photoexcitation of Continuously Stacked Diaroylmethanatoboron Difluoride Molecules with Fused π‐Orbitals in Crystals 下载免费PDF全文
Atsushi Sakai Dr. Eisuke Ohta Yuichi Yoshimoto Mirai Tanaka Dr. Yasunori Matsui Prof. Dr. Kazuhiko Mizuno Prof. Dr. Hiroshi Ikeda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(50):18128-18137
The crystal‐packing structures of seven derivatives of diaroylmethanatoboron difluoride ( 1 a – gBF2 ) are characterized by no overlap of the π‐conjugated main units of two adjacent molecules (type I), overlap of the benzene ring π‐orbitals of two adjacent molecules (type II), and overlap of the benzene and dihydrodioxaborinine rings π‐orbitals of adjacent molecules (type III). The crystal‐packing structures govern the fluorescence (FL) properties in the crystalline states. The FL domain that is present in type I crystals, in which intermolecular orbital interactions are absent, leads to excited monomer‐like FL properties. In the case of the type II crystals, the presence of intermolecular overlap of the benzene rings π‐orbitals generates new FL domains, referred to as “excited multimers”, which possess allowed S0–S1 electronic transitions and, as a result, similar FL lifetimes at longer wavelengths than the FL of the type I crystals. Finally, intermolecular overlap of the benzene and dihydrodioxaborinine ring π‐orbitals in the type III crystals leads to “excited multimer” domains with forbidden S0–S1 electronic transitions and longer FL lifetimes at similar wavelengths as that in type I crystals. 相似文献
104.
Matsuda R Yoshioka Y Akiyama H Aburatani K Watanabe Y Matsumoto T Morishita N Sato H Mishima T Gamo R Kihira Y Maitani T 《Journal of AOAC International》2006,89(6):1600-1608
The labeling of 5 major allergenic ingredients (egg, milk, wheat, buckwheat, and peanut) is mandatory in Japan, and 2 series of enzyme-linked immunosorbent assay (ELISA) kits have been established as official screening methods. However, these official methods have not provided the necessary sensitivity, due in part to poor extraction efficiency. To address this need, 2 novel ELISA kits have been developed: the FASTKIT ELISA Ver. II Series and the FASPEK Allergenic Substances Detection Kit. The new kit systems use an improved extraction buffer that can extract insoluble proteins produced by processing and feature new antibodies that bind to the denatured proteins extracted with the new extraction buffer. The analytical performances of the 2 new ELISA kit series were evaluated in an interlaboratory study. Ten laboratories participated in the study and determined the major allergenic ingredients contained in 5 types of model processed food. The 2 ELISAs displayed fairly good reproducibility and sufficient recovery. 相似文献
105.
Dehydrogenative Carbon–Carbon Bond Formation Using Alkynyloxy Moieties as Hydrogen‐Accepting Directing Groups 下载免费PDF全文
Dr. Yasunori Minami Tatsuro Kodama Prof. Dr. Tamejiro Hiyama 《Angewandte Chemie (International ed. in English)》2015,54(40):11813-11816
In the presence of a catalyst system consisting of Pd(OAc)2, PCy3, and Zn(OAc)2, the reaction of alkynyl aryl ethers with bicycloalkenes, α,ß‐unsaturated esters, or heteroarenes results in the site‐selective cleavage of two C? H bonds followed by the formation of C? C bonds. In all cases, the alkynyloxy group acts as a directing group for the activation of an ortho C? H bond and as a hydrogen acceptor, thus rendering the use of additives such as an oxidant or base unnecessary. 相似文献
106.
107.
Yaoita Y Yoshihara Y Kakuda R Machida K Kikuchi M 《Chemical & pharmaceutical bulletin》2002,50(4):551-553
Two edible mushrooms, Pleurotus eryngii and Panellus serotinus, have been investigated chemically. Two new sterols, 5alpha,9alpha-epidioxy-8alpha,14alpha-epoxy-(22E)-ergosta-6,22-dien-3beta-ol (1) and 3beta,5alpha-dihydroxyergost-7-en-6-one (2), have been isolated from P. eryngii, together with six known ones (3-8). Compound 1 was also isolated from P. serotinus. The structures of the new compounds were elucidated on the basis of their spectral data. 相似文献
108.
Chang CJ Nolan EM Jaworski J Okamoto K Hayashi Y Sheng M Lippard SJ 《Inorganic chemistry》2004,43(21):6774-6779
The synthesis of a difluorofluorescein monocarboxaldehyde platform and its use for preparing ZP8, a new member of the Zinpyr family of neuronal Zn(2+) sensors, are described. By combining an aniline photoinduced electron transfer (PET) switch and an electron-withdrawing fluorescein scaffold, ZP8 displays reduced background fluorescence and improved dynamic range compared to previous ZP probes. The bright sensor undergoes an 11-fold increase in fluorescence intensity upon Zn(2+) complexation (Phi = 0.03-0.35) with high selectivity over cellular concentrations of Ca(2+) and Mg(2+). In addition, sensors in the ZP family have been utilized for optical imaging in biological samples using two-photon microscopy (TPM). The cell-permeable ZP3 probe is capable of identifying natural pools of labile Zn(2+) within the mossy fiber synapses of live hippocampal slices using TPM, establishing the application of this technique for monitoring endogenous Zn(2+) stores. 相似文献
109.
Bis(carbazolylphenyl) and bis(diphenylaminophenyl) derivatives of 1,6-methano[10]annulene, which is luminescent material and contains seven-membered rings, are synthesized. The bis(phenylcarbazole) derivative 3 have high melting point and glass transition temperature. Electroluminescence characteristics of organic light-emitting diodes using these methano[10]annulenes were investigated. 相似文献