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191.
192.
Kaori Umezawa 《Discrete Mathematics》2009,309(13):4656-4660
The graph parameter tree-length, which is defined in terms of Robertson-Seymour’s tree decomposition, was introduced by Dourisboure and Gavoille [Y. Dourisboure, C. Gavoille, Tree-decompositions with bags of small diameter, Discrete Math. 307 (2007) 2008-2029], and has recently been studied. In this paper, we introduce a new graph parameter branch-length, which is defined in terms of Robertson-Seymour’s branch decomposition. We also prove the equivalence between tree-length and branch-length. 相似文献
193.
Kaori Yamazaki 《Acta Mathematica Hungarica》2011,132(1-2):42-48
A classical insertion theorem due to Kat??tov?CTong (or Dowker?CKat??tov, Michael) reads that ? can be a test space for the range of maps on the insertion theorem which characterizes the domain to be normal (or normal and countably paracompact, perfectly normal). It is known that the range ? in the Kat??tov?CTong insertion theorem is not necessarily replaced by a non-trivial separable Banach lattice. We show that the range ? in the Dowker?CKat??tov and Michael insertion theorems can be replaced by any non-trivial separable Banach lattice. 相似文献
194.
Kaori Tateishi Shiori Tsukagoshi Tsuyoshi Nakamura Shotaro Watanabe Vadim A. Soloshonok Osamu Kitagawa 《Tetrahedron letters》2013
We report here the theoretical design and proof of principle of the first example of a conceptually new approach for the preparation of enantiomerically pure compounds from the racemates by chiral initiator-induced Self-Disproportionation of Enantiomers (SDE) via achiral chromatography. 相似文献
195.
196.
Shunsuke Moriya Kaori Iwasaki Keijiro Samejima Koichi Takao Kohfuku Kohda Kyoko Hiramatsu Masao Kawakita 《Analytica chimica acta》2012
An analytical method for the determination of three polyamines (putrescine, spermidine, and spermine) and five acetylpolyamines [N1-acetylspermidine (N1AcSpd), N8-acetylspermidine (N8AcSpd), N1-acetylspermine, N1,N8-diacetylspermidine, and N1,N12-diacetylspermine] involved in the polyamine catabolic pathway has been developed using a hybrid tandem mass spectrometer. Heptafluorobutyryl (HFB) derivatives of these compounds and respective internal standards labeled with stable isotopes were analyzed simultaneously by TOF MS, based on peak areas appearing at appropriate m/z values. The isomers, N1AcSpd and N8AcSpd were determined from their fragment ions, the acetylamidopropyl and acetylamidobutyl groups, respectively, using MS/MS with 13C2-N1AcSpd and 13C2-N8AcSpd which have the 13C2-acetyl group as an internal standard. The TOF MS method was successfully applied to measure the activity of enzymes involved in polyamine catabolic pathways, namely N1-acetylpolyamine oxidase (APAO), spermine oxidase (SMO), and spermidine/spermine N1-acetyltransferase (SSAT). The following natural substrates and products labeled with stable isotopes considering the application to biological samples were identified; for APAO, [4,9,12-15N3]-N1-acetylspermine and [1,4,8-15N3]spermidine (15N3-Spd), respectively; for SMO, [1,4,8,12-15N4]spermine and 15N3-Spd, respectively; and for SSAT, 15N3-Spd and [1,4,8-15N3]-N1-acetylspermidine, respectively. 相似文献
197.
The structure of a complex between heme(Fe(3+)) and a parallel G-quadruplex DNA formed from a single repeat sequence of the human telomere, d(TTAGGG), has been characterized by (1)H NMR. The study demonstrated that the heme(Fe(3+)) is sandwiched between the 3'-terminal G-quartets of the G-quadruplex DNA. Hence, the net +1 charge of the heme(Fe(3+)) in the complex is surrounded by the eight carbonyl oxygen atoms of the G-quartets. Interaction between the heme Fe(3+) and G-quartets in the complex was clearly manifested in the solvent (1)H/(2)H isotope effect on the NMR parameters of paramagnetically shifted heme methyl proton signals, and interaction of the heme Fe(3+) with the eight carbonyl oxygen atoms of the two G-quartets was shown to provide a strong and axially symmetric ligand field surrounding the heme Fe(3+), yielding a heme(Fe(3+)) low-spin species with a highly symmetric heme electronic structure. This finding provides new insights as to the design of the molecular architecture and functional properties of various heme-DNA complexes. 相似文献
198.
K Sugihara J Stucki L Isa J Vörös T Zambelli 《Journal of colloid and interface science》2012,386(1):421-427
Inverted hexagonal blocks of 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) lipid adsorbed on a polyethyleneimine (PEI)-coated surface in deionized water transformed its shape upon the application of an electric field, forming lipid objects in a variety of shapes (e.g. lines with a width of 10-50μm). The phenomenon was driven by the electrophoresis, because the zwitterionic lipid, DOPE turned out to be highly negatively charged in deionized water. The interaction between DOPE and the PEI surface stabilized the system, assuring a lifetime over several weeks for the formed structures after the electric field was switched off. The free-drawing of microscopic objects (lines, crosses, and jelly fish) was also achieved by controlling the direction of the lipid movement with the field direction. 相似文献
199.
Nao Terasaki Dr. Noritaka Yamamoto Dr. Takashi Hiraga Dr. Yoshinori Yamanoi Dr. Tetsu Yonezawa Dr. Hiroshi Nishihara Prof. Tsutomu Ohmori Dr. Makoto Sakai Dr. Masaaki Fujii Prof. Akihiko Tohri Dr. Masako Iwai Dr. Yasunori Inoue Prof. Satoshi Yoneyama Dr. Makoto Minakata Prof. Isao Enami Prof. 《Angewandte Chemie (International ed. in English)》2009,48(9):1585-1587
Plug and play : Photoinduced electron transfer occurs from photoexcited P700 in photosystem I (PSI) to a gold surface (see picture). A novel molecular connector system is used, in which an artificial molecular wire, which is assembled on the gold surface, was plugged into PSI by reconstitution. Analysis of the photoelectron transfer kinetics proved both the output of electrons from PSI and the effectiveness of the molecular wire.
200.
Okubo S Okazaki T Hirose-Takai K Suenaga K Okada S Bandow S Iijima S 《Journal of the American Chemical Society》2010,132(43):15252-15258
The molecular orientation of ellipsoidal C(70) in single-walled carbon nanotubes (SWCNTs) depends on the tube diameter (d(t)). Photoluminescence (PL) studies reveal that the fullerene encapsulation effects on the optical transition energy of SWCNTs are significantly different for C(70) and C(60) at d(t) = 1.405-1.431 nm. This indicates that the transition from the "lying" alignment to the "standing" alignment occurs at d(t) ≈ 1.41 nm and the electronic states of SWCNTs are very sensitive to the interspacing between the encapsulated molecules and the SWCNTs. The present findings suggest that the electronic structure of SWCNTs is tunable not only by alternating the encapsulated molecules but also by controlling their molecular orientations, thus paving the way for development of novel SWCNT-based devices. 相似文献