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961.
Y. Fujiwara 《Few-Body Systems》2014,55(8-10):993-996
Four-cluster Faddeev–Yakubovsky calculations using two-cluster RGM kernels are carried out for identical clusters. A precise ground-state energy of the α-particle, predicted by the quark-model nucleon–nucleon (NN) interaction fss2, is E α = ?26.61 MeV, including approximate effects of the Coulomb force and the charge dependence of the 2N force. The missing ?1.7 MeV in the experimental value ?28.3 MeV is about half of 3–4 MeV, predicted by modern meson-exchange 2N potentials, implying that almost half of 3–4 MeV is attributed to the off-shell effect of our nonlocal NN interaction fss2. As to the applications to four-α system, a method to eliminate the Faddeev redundant components from the basic Faddeev–Yakubovsky equations is proposed. 相似文献
962.
Yasuto Uchimura Dr. Takashi Takeda Dr. Ryo Katoono Prof. Dr. Kenshu Fujiwara Prof. Dr. Takanori Suzuki 《Angewandte Chemie (International ed. in English)》2015,54(13):4010-4013
Upon reduction of a 1H‐cyclobuta[de]naphthalene‐4,5‐diylbis(diarylmethylium) species, a new C? C bond is formed between the Cα and Cortho atoms of the two chromophores, which presents an unprecedented coupling pattern for the dimerization of two trityl units. By attaching an annulated cyclobutane ring at the opposite peri position of the naphthalene core, the distance between the Cα carbon atoms was elongated beyond the limit of σ‐bond formation through “scissor effects”. The suppression of Cα? Cα bond formation, which would lead to hexaphenylethane‐type compounds, is key to the first successful isolation of the α,o‐adducts. The 5‐diarylmethylene‐6‐triarylmethyl‐1,3‐cyclohexadiene unit in the α,o‐adducts is stable, and isomerization of the cyclohexadiene unit into an aromatic system was not observed. The newly formed Cα? Cortho bond was cleaved upon two‐electron oxidation to regenerate the dicationic dye. 相似文献
963.
Formation of Foam‐like Microstructural Carbon Material by Carbonization of Porous Coordination Polymers through a Ligand‐Assisted Foaming Process 下载免费PDF全文
Dr. Kanokwan Kongpatpanich Dr. Satoshi Horike Yu‐ichi Fujiwara Naoki Ogiwara Dr. Hirotomo Nishihara Prof.Dr. Susumu Kitagawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(38):13278-13283
Porous carbon material with a foam‐like microstructure has been synthesized by direct carbonization of porous coordination polymer (PCP). In situ generation of foaming agents by chemical reactions of ligands in PCP during carbonization provides a simple way to create lightweight carbon material with a foam‐like microstructure. Among several substituents investigated, the nitro group has been shown to be the key to obtain the unique foam‐like microstructure, which is due to the fast kinetics of gas evolution during carbonization. Foam‐like microstructural carbon materials showed higher pore volume and specific capacitance compared to a microporous carbon. 相似文献
964.
Tomoko Ishikawa‐Fujiwara Eri Shiraishi Yoshihiro Fujikawa Toshio Mori Tohru Tsujimura Takeshi Todo 《Photochemistry and photobiology》2017,93(1):315-322
Proteins of the cryptochrome/photolyase family (CPF) exhibit sequence and structural conservation, but their functions are divergent. Photolyase is a DNA repair enzyme that catalyzes the light‐dependent repair of ultraviolet (UV)‐induced photoproducts, whereas cryptochrome acts as a photoreceptor or circadian clock protein. Two types of DNA photolyase exist: CPD photolyase, which repairs cyclobutane pyrimidine dimers (CPDs), and 6‐4 photolyase, which repairs 6‐4 pyrimidine–pyrimidone photoproducts (6‐4PPs). Although the Cry‐DASH protein is classified as a cryptochrome, it also has light‐dependent DNA repair activity. To determine the significance of the three light‐dependent repair enzymes in recovering from solar UV‐induced DNA damage at the organismal level, we generated mutants in each gene in medaka using the CRISPR genome editing technique. The light‐dependent repair activity of the mutants was examined in vitro in cultured cells and in vivo in skin tissue. Light‐dependent repair of CPD was lost in the CPD photolyase‐deficient mutant, whereas weak repair activity against 6‐4PPs persisted in the 6‐4 photolyase‐deficient mutant. These results suggest the existence of a heretofore unknown 6‐4PP repair pathway and thus improve our understanding of the mechanisms of defense against solar UV in vertebrates. 相似文献
965.
A hybrid strategy using global analysis of oxidized fatty acids and bioconversion by Bacillus circulans 下载免费PDF全文
966.
Shin Nakamura Takaya Mitsui Kosuke Fujiwara Naoshi Ikeda Yasuhiro Kobayashi Susumu Shimomura 《Hyperfine Interactions》2016,237(1):157
A Mössbauer diffractometer has been developed by using 57Fe nuclear resonant scattering apparatus at SPring-8 BL11XU in order to obtain a crystal-site-selective Mössbauer spectrum. A ??-2?? goniometer was newly installed between the nuclear monochromator and a detector. From a single crystal Fe3 O 4 mounted on the goniometer, the 111, 222, and 220 reflected γ-rays were used to collect the diffraction spectra at room temperature. The intensity ratio of the two subspectra, corresponding to A- and B-site Fe ions, changes notably according to the reflection index. The diffraction spectrum is composed of a major absorption spectrum and a minor emission spectrum. The former is given by the γ-ray due to the electron scattering and nuclear absorption, whereas the latter is given by the γ-ray due to the nuclear resonant scattering. Interference effects between these two γ-rays are also seen as line broadenings, asymmetric line shapes, and slope of the base lines. These features can be successfully expressed by a Fano function. We consider that the emission spectrum due to the nuclear resonant scattering represents crystal-site-selective Mössbauer spectrum. 相似文献
967.
A. Gutierrez M. D. Ashkezari M. Baquero-Ruiz W. Bertsche C. Burrows E. Butler A. Capra C. L. Cesar M. Charlton R. Dunlop S. Eriksson N. Evetts J. Fajans T. Friesen M. C. Fujiwara D. R. Gill J. S. Hangst W. N. Hardy M. E. Hayden C. A. Isaac S. Jonsell L. Kurchaninov A. Little N. Madsen J. T. K. McKenna S. Menary S. C. Napoli P. Nolan K. Olchanski A. Olin P. Pusa C. Ø. Rasmussen F. Robicheaux R. L. Sacramento E. Sarid D. M. Silveira C. So S. Stracka J. Tarlton T. D. Tharp R. I. Thompson P. Tooley M. Turner D. P. van der Werf J. S. Wurtele A. I. Zhmoginov 《Hyperfine Interactions》2015,231(1-3):21-28
We have observed a new mechanism for compression of a non-neutral plasma, where antiprotons embedded in an electron plasma are compressed by a rotating wall drive at a frequency close to the sum of the axial bounce and rotation frequencies. The radius of the antiproton cloud is reduced by up to a factor of 20 and the smallest radius measured is ~ 0.2 mm. When the rotating wall drive is applied to either a pure electron or pure antiproton plasma, no compression is observed in the frequency range of interest. The frequency range over which compression is evident is compared to the sum of the antiproton bounce frequency and the system’s rotation frequency. It is suggested that bounce resonant transport is a likely explanation for the compression of antiproton clouds in this regime. 相似文献
968.
Hiroto Kudo Yusuke Fujiwara Makoto Miyasaka Tadatomi Nishikubo 《Journal of polymer science. Part A, Polymer chemistry》2010,48(24):5746-5751
Polycarbosilanes were synthesized by hydrosilylation reaction of A2 monomer containing bis Si? H moieties and Bn (n = 2, 3, and 4) monomers containing di‐, tri‐, and tetra‐vinyl groups in the presence of Karstedt's catalyst. The corresponding linear polycarbosilanes (LPC) and hyperbranched polycarbosilanes (HBPC) having Mn 2200–51,500 were obtained in 34–94% yield, without any gel product. The values of refractive index (nD) of the synthesized LPC and HBPC were in the range from 1.460 to 1.711, and were consistent with the structures of the synthesized products. In the case of HBPC, the values of nD increased with increase of number‐average molecular weight (Mn), molecular weight distribution (Mw/Mn), and glass transition temperature (Tg), apparently because of increased density due to the presence of microgels, that is, high refractive index hyperbranched carbosilanes could be synthesized by A2 + Bn (n = 3 and 4) method. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
969.
970.
Matsusaburô Fujiwara 《Mathematische Zeitschrift》1926,24(1):161-169
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