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101.
Naofumi Naga Hitomi Nagino Midori Iwashita Tomoharu Miyanaga Hidemitsu Furukawa 《Journal of polymer science. Part A, Polymer chemistry》2015,53(11):1360-1368
Organic–inorganic hybrid gels containing Si‐vinylene units have been synthesized by a hydrosilylation reaction of tri‐ or tetra‐ethynyl aryl compounds, 1,3,5‐triethynylbenzene (TEB), 3,3′,5,5′‐tetraethynylbiphenyl (TEBP), or tetrakis(4‐ethynylphenyl)methane (TEPM), and bisdimethylsilyl compounds, 1,1,3,3‐tetramethyldisiloxane (TMDS) or 1,4‐bisdimetylsilylbenzene (BDMSB), in toluene. Network structure of the resulting gels was quantitatively characterized by a scanning microscopic light scattering. The reactions yielded the gels having homogeneous network structure of 1.5–2.9 nm mesh size under the monomer concentrations that were relatively higher than the critical gelation concentration. The gels obtained from TEB showed broad absorption in the range from 340 to 370 nm, and emission in the range from 440 to 490 nm. The TEB–BDMSB gels showed remarkable red shift of the emission in comparison with that of the corresponding reaction solutions derived from the network formed by σ–π conjugation. The TEPM–TMDS, BDMSB gels exited by 280 nm showed not only the emission peak at around 360 nm derived from TEPM, but the broad peak at around 420 nm, which should be derived from interaction between phenyl groups of TEPM in the gels. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1360–1368 相似文献
102.
Under the Atherton–Todd reaction conditions, the stereochemistry on the reaction of H-phosphinates with different nucleophiles (e.g., amines, alcohols, phenols) was investigated. All reactions took place stereospecifically with inversion of configurations at the phosphorus centers. The reaction might proceed via a phosphoryl chloride intermediate with retention of configuration at phosphorus, followed by the attack of nucleophiles from the backside of Cl to give the substitution products with inversion of configuration at the phosphorus center. A plausible mechanism was proposed for these reactions. 相似文献
103.
Shindo K Kumagai G Takano M Sawada D Saito N Saito H Kakuda S Takagi K Ochiai E Horie K Takimoto-Kamimura M Ishizuka S Takenouchi K Kittaka A 《Organic letters》2011,13(11):2852-2855
C15-Substituted 1α,25-dihydroxyvitamin D(3) analogs were synthesized for the first time to investigate the effects of the modified CD-ring on biological activity concerning the agonistic positioning of helix-3 and helix-12 of the vitamin D receptor (VDR). X-ray cocrystallographic analysis proved that 0.6 ? shifts of the CD-ring and shrinking of the side chain were necessary to maintain the position of the 25-hydroxy group for proper interaction with helix-12. The 15-hydroxy-16-ene derivative showed higher binding affinity for hVDR than the natural hormone. 相似文献
104.
105.
Efficient Asymmetric Hydrogenation of α‐Acetamidocinnamates through a Simple,Readily Available Monodentate Chiral H‐Phosphinate 下载免费PDF全文
Dr. Xiang‐Bo Wang Dr. Midori Goto Dr. Li‐Biao Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(13):3631-3635
An air‐stable, simple (RP)‐mentylbenzylphosphinate, readily available in large quantities, can efficiently induce the rhodium‐catalyzed asymmetric hydrogenation of α‐acetamidocinnamates with high enantioselectivity (up to 99.6 % ee). Intramolecular hydrogen bonding plays an important role in this asymmetric induction. 相似文献
106.
Hiroki Takeshita Midori Sano Kotaro Wada Keita Tamura Masamitsu Miya Katsuhiko Takenaka Tomoo Shiomi 《Colloid and polymer science》2009,287(10):1123-1129
Shrinking kinetics of poly(N-isopropylacrylamide) gels prepared in the presence of a nonionic surfactant C9PE10 was investigated. The shrinking rate of
the gels containing more than 6 wt.% of C9PE10 showed about a thousand-fold increase. From the analysis of the shrinking process
and the small-angle X-ray scattering profiles, the fast shrinking kinetics was attributed to the incorporation of spatial
heterogeneity of the network structure, which is caused by the addition of the surfactant. 相似文献
107.
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109.
Seiji Shinkai Hidefumi Kinda Midori Ishihara Osamu Manabe 《Journal of polymer science. Part A, Polymer chemistry》1983,21(12):3525-3539
The crosslinked polystyrene beads which immobilized two terminal azophenoxide groups of an azobenzene-crown(24-crown-8)-azobenzene unit were synthesized. The polymer beads adsorbed Cs+ in the dark while they rapidly released Cs+ into the solution under UV-light irradiation, and the photoresponsive complexation occurred reversibly. On the other hand, the crosslinked polystyrene beads which immobilized one terminal azophenoxide group of an azobenzene-crown (24-crown-8) unit scarcely (or only to a smaller extent) exhibited such a photoresponsive behavior. Similarly, the polymer beads which immobilized two terminal azophenoxide groups of an azobenzene-crown (18-crown-6) azobenzene unit reversibly adsorbed and desorbed K+ in response to UV-light irradiation. The novel photoresponsive behavior is ascribed to a conformational distortion of the crown rings which induced by the photoisomerization of the azobenzene moiety, although the photoinduced polarity change of the polymer beads is not completely ruled out. The results suggest that the polymer support is useful as a “fixed point” to enforce the conformational changes of immobilized functional molecules. 相似文献
110.
Mohamed S. Abdelfattah Kazufumi Toume Midori A. Arai Hyuma Masu Masami Ishibashi 《Tetrahedron letters》2012,53(26):3346-3348
An unusual alkaloid with a 2-azaquinone-phenylhydrazone structure, katorazone (1), and other metabolites were isolated from the ethyl acetate extract of Streptomyces sp. IFM 11299. The chemical structure of katorazone (1) was elucidated by 1D and 2D NMR analyses together with HR-ESI mass spectrometry. Katorazone (1) showed a synergistic effect in combination with TRAIL and decreased the viability of human gastric adenocarcinoma (AGS) cells. 相似文献