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71.
Inada Y Horikoshi M Nakajima S Kuwata-Gonokami M Ueda M Mukaiyama T 《Physical review letters》2008,101(18):180406
We report on measurements of the critical temperature and the temperature dependence of the condensate fraction for a fermion pair condensate of 6Li atoms. Bragg spectroscopy is employed to determine the critical temperature and the condensate fraction after a fast magnetic field ramp to the molecular side of the Feshbach resonance. Our measurements reveal evidence of level off of the critical temperature and limiting behavior of condensate fraction near the unitarity limit. 相似文献
72.
Li Sheng Tomoya Higashihara Rina Maeda Teruaki Hayakawa Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2013,51(10):2216-2224
A series of block copolystyrene derivatives, poly{[4‐(4‐sulfobutyloxy)styrene]x‐block‐[4‐(n‐butoxystyrene)]y} (PSBOSx‐b‐PnBOSy), containing a flexible alkylsufonated side chain and hydrophobic alkoxy chain with various ion exchange capacities (IECs) have been synthesized based on living anionic polymerization. The resulting crosslinked membranes were prepared using 4,4′‐methylene‐bis[2,6‐bis(hydroxyethyl)phenol] as the crosslinker in the presence of methanesulfonic acid. The crosslinked PSBOS2.2‐b‐PnBOS1 membrane with IEC of 2.89 mequiv g?1 displays a high proton conductivity (0.01 S cm?1) at 30% relative humidity and 80 °C, which is comparable to that of Nafion. The well‐developed phase separation and the continuous hydrophilic domains in the crosslinked PSBOS2.2‐b‐PnBOS1 membranes have been observed in a transmission electron microscope image. Moreover, the dynamic mechanical analysis measurement and Fenton's reagent testing show that the crosslinked PSBOSx‐b‐PnBOSy membranes have good mechanical properties and oxidative stability. These results indicate that the introduction of flexible alkylsulfonated side chains to the polystyrene main chains positively affect both the proton conductivity and oxidative stability. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
73.
Selective introducing of aryl and amino groups: reaction of benzanthrone and organometallic reagents
Rui Umeda Teruaki Namba Tomohiro Yoshimura Masamichi Nakatsukasa Yutaka Nishiyama 《Tetrahedron》2013,69(5):1526-1531
The reaction of benzanthrone and aryl magnesium bromides produced 6-aryl-substituted benzanthrones in moderate to good yields. Similarly, 6-alkylaminobenzanthrones were selectively prepared by the reaction of benzanthrone and lithium alkylamides. In contrast, for the lithium arylamides, the arylamino groups were selectively introduced at the 4-position of the benzanthrone. 相似文献
74.
Ohnishi Teruaki 《Nuclear Physics A》1981,362(2):480-502
The possibility of the production of putative superdense nuclei (SDNs) in the universe is studied with the assumption that the SDNs can certainly be formed when nucleons are compressed over some critical density. Possible nuclear astrophysical processes for SDN production taking place in the early big-bang universe, in interstellar space and in ejection from neutron stars are investigated. It is found that the SDNs cannot be produced at all in a hot universe regardless of the properties of SDNs. The situation that would occur in a cold universe is also discussed. A finite amount of SDNs is found to be formed in interstellar space as the product of high-energy reactions between primary cosmic rays and interstellar matter. It also becomes clear that the astration of SDNs thus formed plays no essential role for the enhancement of the number of SDNs. On the other hand, the SDNs originating from neutron stars are estimated to have a cosmic abundance relative to Si as high as 8 × 10?8??5, which is, apparently, in contradiction with observations. Some implications of this are discussed. 相似文献
75.
Teruaki Mukaiyama 《Tetrahedron》1981,37(23):4111-4119
Various highly stereoselective asymmetric reactions based on chiral diamines having pyrrolidine ring are described. Some of these reactions have been successfully applied to the syntheses of natural products. 相似文献
76.
Yamada T Nagata T Sugi KD Yorozu K Ikeno T Ohtsuka Y Miyazaki D Mukaiyama T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(18):4485-4509
The highly enantioselective borohydride reduction of aromatic ketones or imines to the corresponding alcohols was developed in the presence of a catalytic amount of an optically active cobalt(II) complex catalyst. This enantioselective reduction is carried out using a precisely premodified borohydride with alcohols such as tetrahydrofurfuryl alcohol, ethanol and methanol. High optical yields are obtained by choosing the appropriate alcohol as modifiers and a suitable beta-ketoiminato ligand of the catalyst. The enantioselective borohydride reduction has been successfully applied to the preparation of optically active 1,3-diols, the stereoselective reduction of diacylferrocenes, and dynamic and/or kinetic resolution of 1,3-dicarbonyl compounds. 相似文献
77.
We consider a representation of the entropy production for a completely positive, trace-preserving dynamical semigroup satisfying detailed balance with respect to its faithful stationary state denned on aW*-algebra(): it is expressed as a positive Hermitian form on(), which is analogous to the quantum correlation functions used in the Kubo theory. By considering this Hermitian form as a variation function of a vector in(), an exact characterization of the stationary states of semigroups in a certain class is obtained. On this basis, the problem of characterizing the stationary states discussed by Spohn and Lebowitz for manyreservoir open systems is solved without the restriction to situations near thermal equilibrium. 相似文献
78.
Ge Z Hayakawa T Ando S Ueda M Akiike T Miyamoto H Kajita T Kakimoto MA 《Organic letters》2008,10(3):421-424
The electronic structures of eight bathophenanthroline derivatives were elucidated by DFT calculations, and four representatives of which CZBP, m-CZBP, m-TPAP, and BPABP were synthesized and employed as the hosts to afford highly efficient phosphorescent OLEDs. The calculated molecular orbital energies agree well with the experimental results, which further demonstrates that the localization of HOMO and LUMO at the respective hole- and electron-transporting moieties is desirable in bipolar molecular designs. 相似文献
79.
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