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181.
Nakano K Kawata S Yoneda K Fuyuhiro A Yagi T Nasu S Morimoto S Kaizaki S 《Chemical communications (Cambridge, England)》2004,(24):2892-2893
The variable temperature magnetic susceptibility, X-ray crystallography, and IR and Raman spectra of a new dinuclear complex [{Fe(II)(NCBH(3))(4-phpy)}(2) mu-bpypz)(2)] demonstrated the first two-step spin-crossover associated with a 1 : 1 mixture of high-spin pair [HS-HS] and low-spin pair [LS-LS] at the plateau. 相似文献
182.
Eguchi K Enomoto S Furuno K Goldman J Hanada H Ikeda H Ikeda K Inoue K Ishihara K Itoh W Iwamoto T Kawaguchi T Kawashima T Kinoshita H Kishimoto Y Koga M Koseki Y Maeda T Mitsui T Motoki M Nakajima K Nakajima M Nakajima T Ogawa H Owada K Sakabe T Shimizu I Shirai J Suekane F Suzuki A Tada K Tajima O Takayama T Tamae K Watanabe H Busenitz J Djurcic Z McKinny K Mei DM Piepke A Yakushev E Berger BE Chan YD Decowski MP Dwyer DA Freedman SJ Fu Y Fujikawa BK Heeger KM Lesko KT Luk KB Murayama H 《Physical review letters》2003,90(2):021802
KamLAND has measured the flux of nu;(e)'s from distant nuclear reactors. We find fewer nu;(e) events than expected from standard assumptions about nu;(e) propagation at the 99.95% C.L. In a 162 ton.yr exposure the ratio of the observed inverse beta-decay events to the expected number without nu;(e) disappearance is 0.611+/-0.085(stat)+/-0.041(syst) for nu;(e) energies >3.4 MeV. In the context of two-flavor neutrino oscillations with CPT invariance, all solutions to the solar neutrino problem except for the "large mixing angle" region are excluded. 相似文献
183.
A new efficient system for transporting saccharides through a liquid membrane has been constructed. The transport rates of saccharides were accelerated greatly by the cyclodextrin dimer 2; by contrast, the corresponding cyclodextrin monomer 1 was not effective at mediating saccharide transport. The transport rate of D-ribose through a chloroform liquid membrane was 17 times faster when the cyclodextrin dimer 2 was used as the transporter than when the cyclodextrin monomer 1 was used. Similarly the transport rate of methyl D-galactopyranoside was 16 times faster by 2 than by 1. 相似文献
184.
An efficient method has been developed for the first solid-phase synthesis of HTLV-1 protease inhibitors that contain hydroxyethylamine isostere as a transition-state mimetic. The synthetic procedure was designed to allow the evaluation of stereostructure-activity relationships at the scissile site. All the possible configurations at the hydroxy- and side chain-bearing asymmetric centers of the isostere were constructed by an ester-derived asymmetric aldol reaction. Each inhibitor containing the isostere backbone was synthesized on solid support by using the newly developed succinate ester linker. The configuration at the hydroxy- and side chain-bearing asymmetric center showed remarkable effects on the inhibitory activity; the K(i) value changed with approximately 2 orders of magnitude. The described approach enables an efficient preparation of the inhibitors containing secondary alcohol as a transition-state mimetic. 相似文献
185.
Simple bis(imidazolyl)porphyrin cobalt(III) complex was found to form a long polymeric array by complementary coordination of imidazole to cobalt ion. Formation of higher ordered assemblies was also observed. 相似文献
186.
Hatano T Takeuchi M Ikeda A Shinkai S 《Chemical communications (Cambridge, England)》2003,(3):342-343
It was found that [60]fullerene encapsulated in anionic calix[8]arenes can be readily deposited by electrochemical oxidative polymerization of ethylenedioxythiophene: the resultant electrode generates a photocurrent wave (ca. 100 nA cm(-2)) in response to visible light irradiation. 相似文献
187.
Sugasaki A Sugiyasu K Ikeda M Takeuchi M Shinkai S 《Journal of the American Chemical Society》2001,123(42):10239-10244
We have designed phenylboronic acid group appended Ce(IV) bis(porphyrinate) double decker 1 and meso-meso linked porphyrin 2, useful for the allosteric binding of biologically important saccharides, Lewis oligosaccharides. Compound 1 binds Lewis oligosaccharides in aqueous media because of the boronic acid-diol interaction, but the complexation event can occur only above the critical concentrations because of the sigmoidal [oligosaccharide] versus [complex] isotherm. Compound 1 has a sufficiently high affinity with Lewis oligosaccharides (K = 10(5)-10(6) M(-2)) with Hill coefficients n of 1.8-2.0, and Lewis(X) series and Lewis(a) series give opposite, symmetrical CD spectra. This is the first example of efficient binding of Lewis oligosaccharides to the artificial receptor, which has become possible by positive homotropic allosterism. 相似文献
188.
Ida K Funaba H Kado S Narihara K Tanaka K Takeiri Y Nakamura Y Ohyabu N Yamazaki K Yokoyama M Murakami S Ashikawa N deVries PC Emoto M Goto M Idei H Ikeda K Inagaki S Inoue N Isobe M Itoh K Kaneko O Kawahata K Khlopenkov K Komori A Kubo S Kumazawa R Liang Y Masuzaki S Minami T Miyazawa J Morisaki T Morita S Mutoh T Muto S Nagayama Y Nakanishi H Nishimura K Noda N Notake T Kobuchi T Ohdachi S Ohkubo K Oka Y Osakabe M Ozaki T Pavlichenko RO Peterson BJ Sagara A Saito K Sakakibara S Sakamoto R 《Physical review letters》2001,86(23):5297-5300
Recent large helical device experiments revealed that the transition from ion root to electron root occurred for the first time in neutral-beam-heated discharges, where no nonthermal electrons exist. The measured values of the radial electric field were found to be in qualitative agreement with those estimated by neoclassical theory. A clear reduction of ion thermal diffusivity was observed after the mode transition from ion root to electron root as predicted by neoclassical theory when the neoclassical ion loss is more dominant than the anomalous ion loss. 相似文献
189.
Narihara K Watanabe KY Yamada I Morisaki T Tanaka K Sakakibara S Ida K Sakamoto R Ohyabu N Ashikawa N Emoto M Funaba H Goto M Hayashi H Idei H Ikeda K Inagaki S Inoue N Kaneko O Kawahata K Kobuchi T Komori A Kubo S Kumazawa R Masuzaki S Miyazawa J Morita S Motojima O Murakami S Muto S Mutoh T Nagayama Y Nakamura Y Nakanishi H Nishimura K Noda N Notake T Ohdachi S Oka Y Ohkubo K Osakabe M Ozaki S Peterson BJ Sagara A Saito K Sasao H Sasao M Sato K Sato M Seki T Shimozuma T Shoji C Sudo S 《Physical review letters》2001,87(13):135002
It was observed that the vacuum magnetic island produced by an external error magnetic field in the large helical device shrank in the presence of plasma. This was evidenced by the disappearance of flat regions in the electron temperature profile obtained by Thomson scattering. This island behavior depended on the magnetic configuration in which the plasmas were produced. 相似文献
190.
N. Ikeda 《Physica A》2007
We propose a model of time evolving networks in which a kind of transport between vertices generates new edges in the graph. We call the model “Network formed by traces of random walks”, because the transports are represented abstractly by random walks. Our numerical calculations yield several important properties observed commonly in complex networks, although the graph at initial time is only a one-dimensional lattice. For example, the distribution of vertex degree exhibits various behaviors such as exponential, power law like, and bi-modal distribution according to change of probability of extinction of edges. Another property such as strong clustering structure and small mean vertex–vertex distance can also be found. The transports represented by random walks in a framework of strong links between regular lattice is a new mechanisms which yields biased acquisition of links for vertices. 相似文献