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151.
Tokumoto T Brooks JS Oshima Y Choi ES Brunel LC Akutsu H Kaihatsu T Yamada J van Tol J 《Physical review letters》2008,100(14):147602
Electron spin resonance reveals the spin behavior of conduction (pi) and localized (d) electrons in beta-(BDA-TTP)2MCl4 (M=Fe, Ga). Both the Ga3+(S=0) and Fe3+(S=5/2) compounds exhibit a metal-insulator transition at 113 K with the simultaneous formation of a spin-singlet ground state in the pi electron system of the donor molecules. The behavior is consistent with charge ordering in beta-(BDA-TTP)2MCl4 at the metal-insulator transition. At 5 K, the Fe3+ compound orders antiferromagnetically, even though the pi electrons, which normally would facilitate magnetic exchange, are localized nonmagnetic singlets. 相似文献
152.
Guang Liu Lakshmi Chakka Joseph E. Gadzia R. Suzuki N. Oshima 《Applied Surface Science》2008,255(1):115-118
Positronium annihilation lifetime (PAL) spectroscopy and Doppler broadening energy spectra (DBES) have been used to search for selectivity and sensitivity for cancerous skin samples with and without cancer. This study is to further explore the melanoma cancerous system and other different types of skin samples. We found that the S parameter in melanoma skin samples cut at 0.39 mm depth from the same patient's skin is smaller than near the skin surface. However in 10 melanoma samples from different patients, the S parameters vary significantly. Similarly, among 10 normal skin samples without cancer, the S parameters also vary largely among different patients. To understand the sensitivity of PAS as a tool to detect cancer formation at the early stage, we propose a controlled and systematic study of in vivo experiments using UV-induced cancer skin from living animals. 相似文献
153.
LIU Yuan ZHOU Xiao-Hong ZHANG Yu-Hu ZHENG-Yong LIU Min-Liang GUO Ying-Xiang M. Oshima Y. Toh M. Koizumi A. Osa Y. Hatsukawa SUN Yang 《中国物理快报》2008,25(5):1633-1635
A standard in-beam γ-spectroscopy experiment for 188Pt is performed via the176Yb(18O, 6n) reaction at beam energies of 88 and 95MeV, and the level scheme for 188Pt is established. Prolate and oblate shape coexistence has been demonstrated to occur in 188Pt by applying the projected shell model. The rotation alignment of i13/2 neutrons drives the yrast sequence changingsuddenly from prolate to oblate shape at angular momentum 10h, indicating likely a new type of shape phase transition along the yrast line in 188Pt. 相似文献
154.
Gert-Jan Bekker Mitsugu Araki Kanji Oshima Yasushi Okuno Narutoshi Kamiya 《Journal of computational chemistry》2020,41(17):1606-1615
Multicanonical molecular dynamics based dynamic docking was used to exhaustively search the configurational space of an inhibitor binding to the N-terminal domain of heat-shock protein 90 (Hsp90). The obtained structures at 300 K cover a wide structural ensemble, with the top two clusters ranked by their free energy coinciding with the native binding site. The representative structure of the most stable cluster reproduced the experimental binding configuration, but an interesting conformational change in Hsp90 could be observed. The combined effects of solvation and ligand binding shift the equilibrium from a preferred loop-in conformation in the unbound state to an α-helical one in the bound state for the flexible lid region of Hsp90. Thus, our dynamic docking method is effective at predicting the native binding site while exhaustively sampling a wide configurational space, modulating the protein structure upon binding. 相似文献
155.
156.
A highly efficient and mild method for the synthesis of 1,5-hexadienes, nickel-catalyzed reactions of Boc-protected allyl alcohols with homoallyl alcohols, has been developed. Nickel-mediated retro-allylation allows for the use of homoallyl alcohols as allylmetal equivalents in the synthesis of 1,5-hexadienes. 相似文献
157.
The AlCl3-catalyzed acetylation of 1,2-hydrophenylated [60]fullerenes, HC60-Ar, proceeded via a sequential manner involving the acetylation at the hydrogenated fullerene carbon, the following intramolecular cyclization with the adjacent aryl group, the facile loss of water, and the second acetylation of the generated indenylidene double bond. However, the similar reaction of the hydrobiphenylated analogue brought about the normal acetylation at the terminal aromatic ring prior to the same sequential reactions as did hydrophenylated fullerenes. 相似文献
158.
Vinylcyclopropanes bearing one or two electron-withdrawing groups on the cyclopropane ring undergo nickel-catalyzed borylative ring opening with bis(pinacolato)diboron to yield allylic boronates. The reaction proceeded with high E selectivity. 相似文献
159.
Treatment of alkyl halides, including tertiary alkyl bromides, with cyclopentadienylmagnesium bromide in the presence of a catalytic amount of copper(II) triflate yielded the corresponding cyclopentadienylated products in high yields. The following hydrogenation of the products provided alkyl-substituted cyclopentanes. 相似文献
160.
Oshita K Seo K Sabarudin A Oshima M Takayanagi T Motomizu S 《Analytical and bioanalytical chemistry》2008,390(7):1927-1932
A chitosan resin possessing a phenylarsonic acid moiety (phenylarsonic acid type chitosan resin) was developed for the collection
and concentration of trace uranium prior to inductively coupled plasma (ICP) atomic emission spectrometry (AES) measurement.
The adsorption behavior of 52 elements was systematically examined by packing it in a minicolumn and measuring the elements
in the effluent by ICP mass spectrometry. The resin could adsorb several cationic species by a chelating mechanism, and several
oxo acids, such as Ti(IV), V(V), Mo(VI), and W(VI), by an anion-exchange mechanism and/or a chelating mechanism. Especially,
U(VI) could be adsorbed almost 100% over a wide pH region from pH 4 to 8. Uranium adsorbed was easily eluted with 1 M nitric
acid (10 mL), and the 25-fold preconcentration of uranium was achieved by using a proposed column procedure, which could be
applied to the determination of trace uranium in seawater by ICP-AES. The limit of detection was 0.1 ng mL−1 for measurement by ICP-AES coupled with 25-fold column preconcentration. 相似文献