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101.
Ken-ichi Mimura Kosuke Hiramatsu Makoto Moriya Wataru Sakamoto Satoshi Kawado Yoshiaki Uesu Toshinobu Yogo 《Journal of nanoparticle research》2010,12(5):1933-1943
A transparent BaTiO3 particle/polymer hybrid was synthesized from a Ba–Ti double alkoxide modified with an organic ligand and its refractive index
and second harmonic generation were studied. BaTiO3 particles modified with 2-vinyloxyethanol (ethylene glycol monovinyl ether, EGMVE) were polymerized with methyl methacrylate
(MMA) yielding the transparent BaTiO3 particle/poly MMA hybrid. X-ray photoelectron spectra indicated that the formation of chemical bonds between BaTiO3 nanoparticles and the organic matrix. The refractive indexes of the hybrid films depended on the crystallite size of BaTiO3 nanoparticles and the volume fractions of BaTiO3 and polymer phases. The hybrid film synthesized at BaTiO3/8EGMVE/30H2O/PMMA revealed a refractive index of 1.65 at 589 nm with an Abbe number of 54. The hybrid film exhibited a second harmonic
wave of 532 nm on irradiation with a fundamental wave of 1,064 nm. 相似文献
102.
Hajime Moriya 《Communications in Mathematical Physics》2006,264(2):411-426
We discuss fermion grading symmetry for quasi-local systems with graded commutation relations. We introduce a criterion of
spontaneously symmetry breaking (SSB) for general quasi-local systems. It is formulated based on the idea that each pair of
distinct phases (appeared in spontaneous symmetry breaking) should be disjoint not only for the total system but also for
every complementary outside system of a local region specified by the given quasi-local structure. Under a completely model
independent setting, we show the absence of SSB for fermion grading symmetry in the above sense.
We obtain some structural results for equilibrium states of lattice systems. If there would exist an even KMS state for some
even dynamics that is decomposed into noneven KMS states, then those noneven states inevitably violate our local thermal stability
condition. 相似文献
103.
Diastereoselective Synthesis of Open‐Chain Secondary Alkyllithium Compounds and Trapping Reactions with Electrophiles 下载免费PDF全文
Dr. Guillaume Dagousset Kohei Moriya Rasmus Mose Dr. Guillaume Berionni Prof. Dr. Konstantin Karaghiosoff Prof. Dr. Paul Knochel 《Angewandte Chemie (International ed. in English)》2014,53(5):1425-1429
A practical stereoselective iodide–lithium exchange was used in the first general preparation of functionalized stereodefined acyclic secondary nonstabilized lithium reagents from the corresponding secondary alkyl iodides. These lithium reagents react with various electrophiles including carbon electrophiles with high retention of configuration. Kinetic data on the configurational stability of these acyclic alkyllithium reagents are given. This methodology offers a new entry to chiral synthons for the stereoselective synthesis of open‐chain molecules. 相似文献
104.
Takaoki Ishii Ryo Watanabe Toshimitsu Moriya Prof. Dr. Hirohisa Ohmiya Prof. Dr. Seiji Mori Prof. Dr. Masaya Sawamura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(40):13547-13553
Catalyst–substrate hydrogen bonds in artificial catalysts usually occur in aprotic solvents, but not in protic solvents, in contrast to enzymatic catalysis. We report a case in which ligand–substrate hydrogen‐bonding interactions cooperate with a transition‐metal center in alcoholic solvents for enantioselective catalysis. Copper(I) complexes with prolinol‐based hydroxy amino phosphane chiral ligands catalytically promoted the direct alkynylation of aldehydes with terminal alkynes in alcoholic solvents to afford nonracemic secondary propargylic alcohols with high enantioselectivities. Quantum‐mechanical calculations of enantiodiscriminating transition states show the occurrence of a nonclassical sp3‐C? H???O hydrogen bond as a secondary interaction between the ligand and substrate, which results in highly directional catalyst–substrate two‐point hydrogen bonding. 相似文献
105.
Toshio Koizumi Nobuyoshi Saeki Hisatoshi Abematsu Shu-Ichi Terada Osamu Moriya Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》1999,37(16):3419-3426
Synthesis and radical polymerization behavior of N-vinylsaccharin (1) are described. Radical homopolymerization of 1 was carried out in the presence of a radical initiator for 24 h to afford the polymer containing a saccharin moiety in the side group, which was insoluble in common organic solvents. Among the copolymers of 1 with various vinyl monomers such as vinyl acetate (VAc), methyl acrylate (MA), acrylonitrile (AN), and styrene (St), only the copolymer [copoly(1-St)] obtained from 1 and St was soluble in common organic solvents. In the copolymerization of 1 and St, the Q and e values of 1 were estimated to be 0.10 and −1.60, respectively. These values are similar to those of N-vinylphthalimide (Q = 0.36, e = −1.52). The reaction of copoly(1-St) with LiAlH4 was carried out in THF for 24 h to convert the saccharin moiety into the ring-opened structure bearing hydroxy and sulfonamide groups. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3419–3426, 1999 相似文献
106.
In our previous report a new methodology for intermolecular cross-linking or bridging of protein utilizing a spontaneous chelate formation process was proposed. In this paper the reliability of the process as a tool for protein immobilization has been further evaluated. The chromatographic behavior of tryptophan in a column packed with Sepharose coupled with salicylaldehyde residue showed that the alpha-amino acid was bound tightly to the gel in the presence of copper(II) ion and was eluted by the addition of ethylenediaminetetraacetate (EDTA). It was also proved that subtilisin modified with an alpha-amino acid residue was immobilized on the column, and this binding was reversed by the addition of EDTA as well. 相似文献
107.
We show some distinct features of quantum entanglement for bipartite CAR systems such as the failure of triangle inequality of von Neumann entropy and the possible change of our entanglement degree under local operations. Those are due to the nonindependence of CAR systems and never occur in any algebraic independent systems. We introduce a new notion half-sided entanglement. 相似文献
108.
T. Kikuchi T. Motobayashi N. Iwasa Y. Ando M. Kurokawa S. Moriya H. Murakami T. Nishio J. Ruan S. Shirato S. Shimoura T. Uchibori Y. Yanagisawa T. Kubo H. Sakurai T. Teranishi Y. Watanabe M. Ishihara M. Hirai T. Nakamura S. Kubono M. Gai R.H. France III K.I. Hahn T. Delbar P. Lipnik C. Michotte 《The European Physical Journal A - Hadrons and Nuclei》1998,3(3):213-215
We have measured the dissociation of 8B in the Coulomb field of 208Pb at Ein=51.9 MeV/nucleon and extracted the cross section of the 7Be(p,γ)8B reaction at 0.4 ≤ Erel≤ 3 MeV, which is of importance for the 8B solar-neutrino production rate. The extracted astrophysical S17 factors are consistent with our earlier Coulomb dissociation measurement, and agree with the values deduced from the direct
capture measurements by Filippone et al., Vaughn et al. and Hammache et al. The S factor at zero energy was extracted to be
18.9±1.8 eV-b with the help of theoretical energy-dependence.
Received: 15 August 1998 相似文献
109.
110.
Dr. Nina Hartrampf Dr. Toshiyuki Seki Dr. Andreas Baumann Philip Watson Nynke A. Vepřek Belinda E. Hetzler Prof. Dr. Anja Hoffmann-Röder Prof. Dr. Moriya Tsuji Prof. Dr. Dirk Trauner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(20):4476-4479
α-Galactosylceramides are glycosphingolipids that show promise in cancer immunotherapy. After presentation by CD1d, they activate natural killer T cells (NKT), which results in the production of a variety of pro-inflammatory and immunomodulatory cytokines. Herein, we report the synthesis and biological evaluation of photochromic derivatives of KRN-7000, the activity of which can be modulated with light. Based on established structure–activity relationships, we designed photoswitchable analogues of this glycolipid that control the production of pro-inflammatory cytokines, such as IFN-γ. The azobenzene derivative α-GalACer-4 proved to be more potent than KRN-7000 itself when activated with 370 nm light. Photolipids of this type could improve our mechanistic understanding of cytokine production and could open new directions in photoimmunotherapy. 相似文献