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排序方式: 共有323条查询结果,搜索用时 15 毫秒
31.
In this note, inequalities between the distance degrees of distance degree regular graphs and to characterize the graphs when one of the equalities holds are proved. 相似文献
32.
Katsuyuki Ogura Kazuo Ohtsuki Masami Nakamura Nobuhiro Yahata Kazumasa Takahashi Hirotada Iida 《Tetrahedron letters》1985,26(20):2455-2458
Methylthiomethyl p-tolyl sulfone (1) was conveniently alkylated to give mono- and dialkylated products (2 and 4). Reaction conditions for the trasformation of 2 and 4 into aldehydes (3) and ketones (5), respectively, were exploited. 相似文献
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35.
Cai YQ Chow PC Restrepo OD Takano Y Togano K Kito H Ishii H Chen CC Liang KS Chen CT Tsuda S Shin S Kao CC Ku W Eguiluz AG 《Physical review letters》2006,97(17):176402
A sharp feature in the charge-density excitation spectra of single-crystal MgB2, displaying a remarkable cosinelike, periodic energy dispersion with momentum transfer (q) along the c* axis, has been observed for the first time by high-resolution nonresonant inelastic x-ray scattering (NIXS). Time-dependent density-functional theory calculations show that the physics underlying the NIXS data is strong coupling between single-particle and collective degrees of freedom, mediated by large crystal local-field effects. As a result, the small-q collective mode residing in the single-particle excitation gap of the B pi bands reappears periodically in higher Brillouin zones. The NIXS data thus embody a novel signature of the layered electronic structure of MgB2. 相似文献
36.
Y. Kondo T. Nakamura Y. Satou T. Matsumoto N. Aoi N. Endo N. Fukuda T. Gomi Y. Hashimoto M. Ishihara S. Kawai M. Kitayama T. Kobayashi Y. Matsuda N. Matsui T. Motobayashi T. Nakabayashi T. Okumura H.J. Ong T.K. Onishi K. Ogata H. Otsu H. Sakurai S. Shimoura M. Shinohara T. Sugimoto S. Takeuchi M. Tamaki Y. Togano Y. Yanagisawa 《Physics letters. [Part B]》2010
37.
K. Tshoo Y. Satou H. Bhang S. Choi T. Nakamura S. Deguchi Y. Kawada Y. Kondo N. Kobayashi Y. Nakayama K. N. Tanaka N. Tanaka N. Aoi M. Ishihara T. Motobayashi H. Otsu H. Sakurai S. Takeuchi Y. Togano K. Yoneda Z. H. Li F. Delaunay J. Gibelin F. M. Marques N. A. Orr T. Honda M. Matsushita T. Kobayashi Y. Miyashita T. Sumikama K. Yoshinaga S. Shimoura D. Sohler T. Zheng Z.X. Cao 《Few-Body Systems》2013,54(1-4):459-463
The unbound excited states of the most neutron-rich dripline oxygen isotope, 24O, have been investigated by using the 24O(p,p′)24O* reaction at the beam energy of 62 MeV/nucleon in inverse kinematics. The first and second unbound excited states of 24O have been observed at ${E_{\rm x}= 4.63_{-0.14}^{+0.30}}$ MeV and ${E_{\rm x}= 5.13_{-0.24}^{+0.19}}$ MeV (preliminary) along with the evidence for another higher lying state at around 7.3 MeV. The quadrupole deformation parameter ${\beta_{2^+}}$ was deduced to be ${0.15_{-0.03}^{+0.08}}$ (preliminary) for the first time. The systematics of the ${\beta_{2^+}}$ and the ${E_{\rm x}(2_1^+)}$ in the Z = 8 isotopes shows the N = 16 spherical shell closure in 24O. 相似文献
38.
Recyclable carbon fiber‐reinforced plastics (CFRP) containing degradable acetal linkages: Synthesis,properties, and chemical recycling 下载免费PDF全文
Ayaka Yamaguchi Tamotsu Hashimoto Yoshinori Kakichi Michio Urushisaki Toshikazu Sakaguchi Kazumasa Kawabe Keiichi Kondo Hirohumi Iyo 《Journal of polymer science. Part A, Polymer chemistry》2015,53(8):1052-1059
Two epoxy resins containing degradable acetal linkages were synthesized by the reaction of cresol novolak‐type phenolic resin (CN) with vinyl ethers containing a glycidyl group [cyclohexane dimethanol vinyl glycidyl ether (CHDMVG) and 4‐vinyloxybutyl glycidyl ether (VBGE). Carbon fiber‐reinforced plastics (CFRPs) were prepared by heating laminated prepreg sheets with CN‐CHDMVG resin (derived from CN and CHDMVG) and CN‐VBGE resin (derived from CN and VBGE), in which carbon fibers are impregnated with epoxy resins containing curing agents [dicyandiamide (DICY)] and curing accelerator [3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea (DCMU)]. CN‐CHDMVG‐based CFRPs and CN‐VBGE‐based CFRPs exhibited almost the same tensile strength as the conventional bisphenol‐A‐based CFRPs. CN‐CHDMVG‐based CFRPs and CN‐VBGE‐based CFRPs underwent smooth breakdown with the treatment of hydrochloric acid in tetrahydrofuran at room temperature for 24 h to regenerate strands of carbon fibers. The surface conditions of the recovered carbon fibers had little changes during degradation and recovery processes on the basis of scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS). The recovered carbon fibers exhibited almost the same tensile strength as virgin carbon fibers and hence would be reused for the production of CFRPs. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1052–1059 相似文献
39.
Masaki Matsui Yuya Tsuzuki Yasuhiro Kubota Kazumasa Funabiki Toshiyasu Inuzuka Kazuhiro Manseki Shinji Higashijima Hidetoshi Miura Hiroyasu Sato Tsukasa Yoshida 《Tetrahedron》2018,74(40):5867-5878
(2R,3aR,8bR)- and (2S,3aS,8bS)-2-Methyl indoline dye tetrabutylammonium carboxylates exhibited the highest conversion efficiency among four regio and stereo isomers. These indoline dyes also showed higher conversion efficiency than DN350. 相似文献
40.
The composition dependences of molar volume and elastic constants were investigated for sodium and potassium germanate glasses of composition xR2O·GeO2 (O < x < 0.65 in the sodium-glasses and O < x < 0.75 in the potassium-ones). The variation of the molar volume could be approximated by straight lines crossing at 0.18 and 0.16 in x in the sodium- and potassium-glasses, respectively. At these compositions the elastic constants showed maxima. With reference to the structures of several alkali germanate crystals, it was concluded that the fraction of GeO6 units, N6, reaches a maximum at 0.18 in x in the sodium-glasses (15.6) mol.% Na2O) and at 0.16 in x in the potassium-glasses (13.8 mol.% K2O). It was also considered that N6 is not null at 0.5 but is null probably at 1.0 in x in the glasses. A network model of the germanate glasses was discussed. 相似文献