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1.
Koichi Mikami Yukinori Yusa Manabu Hatano Kazuki Wakabayashi Kohsuke Aikawa 《Tetrahedron》2004,60(20):4475-4480
A tropos rhodium(I) complex having skewphos ligand is shown to be a highly enantioselective catalyst for asymmetric ene-type carbocyclization of 1,6-enynes with tri-substituted olefins to control quaternary stereogenic centers or spiro-rings. 相似文献
2.
A simple method for the diastereoselective synthesis of racemic 1,2-diol mediated by low-valence niobium generated in situ is described. A 1,4-dioxane-toluene solvent system was found to be essential to achieve higher selectivities and to prevent other reactions of pinacols, such as deoxygenation and acetal formation. Aromatic aldehydes and ketones were converted to the corresponding pinacols with up to 97 and 85% de, respectively. 相似文献
3.
4.
Hideaki Hioki Yumiko Ohnishi Miwa Kubo Emi Nashimoto Yukinori Kinoshita Miho Samejima Mitsuaki Kodama 《Tetrahedron letters》2004,45(3):561-564
A fluorescence-labeled calix[4]arene library substituted with peptides at the upper rim was synthesized. Screening of the library for binding a dye-labeled oligopeptide indicated that some peptidocalix[4]arenes selectively bind the oligopeptide. The chemosensitivity of the library members for a target peptide was also investigated. 相似文献
5.
6.
Takahiro Gunji Yukinori Nagao Takahisa Misono Yoshimoto Abe 《Journal of polymer science. Part A, Polymer chemistry》1992,30(3):371-377
From polytitanosiloxanes (PTS), SiO2–TiO2 oxide fibers with fairly good tensile strength were prepared, and their mechanical and thermal properties were investigated. The precursor fibers PTS-0.5 and PTS-1.0 were obtained by dry spinning of a highly viscous PTS solution which were formed as the reaction mixture of silicic acid (SA) with bis(2,4-pentanedionato)titanium diisopropoxide (PTP) in the molar ratios (SA/PTP) of 0.5 and 1.0. The precursor fibers PTS-0.5 were too brittle to measure their tensile strength, whereas PTS-1.0 and the heat-treated fibers were found to have tensile strength of 130 (precursor), 540 (500°C), and 450 (900°C) MPa, respectively. Heat-treatment of the fibers PTS-1.0 at above 1000°C forms anatase and rutile of titanium dioxide. The crystallization is resulted from the unreacted PTP which is not incorporated into the polymer network. 相似文献
7.
Yoshiyuki Koyano Norio Takenaka Yukinori Nakagawa Masataka Nagaoka 《Journal of computational chemistry》2010,31(14):2628-2641
8.
Eguchi Y 《Biomedical chromatography : BMC》2002,16(8):500-503
Lipoprotein lipase (LPL) is a key enzyme which regulates the plasma triglyceride concentration by hydrolyzing triglycerides in chylomicrons and very-low-density lipoprotein (VLDL). The activity of LPL was conventionally analyzed using radio-labeled residues or direct sandwich-ELISA. An assay for lipoprotein lipase activity which used a nonradioactive substrate, tri-olein, is described. In this method, LPL activity was detected fluorometrically by reacting 9-anthryldiazomethane (ADAM) with the oleic acid generated from tri-olein by enzyme activity and separated by reversed-phase HPLC. This method has been optimized and the optimum enzyme incubation time and reaction time of the generated oleic acid with ADAM were both at 20 min. The method correlated well with the conventional method. 相似文献
9.
[reaction: see text] The tropos (chirally flexible) or atropos (chirally rigid) nature of BIPHEP-Rh complexes at room temperature critically depends on the amines complexed. The aliphatic DPEN complex is atropos, whereas the aromatic DABN complex is tropos. BIPHEP-Rh chirality can thus be controlled by DABN at room temperature. The amine-free BIPHEP-Rh complex is tropos. At 5 degrees C, even amine-free BIPHEP-Rh complexes are atropos and hence can be used as enantiopure catalysts to give high enantioselectivity in ene-type cyclization of 1,6-enynes. 相似文献
10.
Chiba JY Tanaka K Ohshiro Y Miyake R Hiraoka S Shiro M Shionoya M 《The Journal of organic chemistry》2003,68(2):331-338
This paper describes a convenient synthetic procedure for nucleoside mimics, 1-6, in which the 3',5'-hydroxy groups of natural 2'-deoxythymidine or 2'-deoxyadenosine are replaced by thiol, amine, or alkylthiol groups. Such nucleosides would be built up into a single DNA strand with cooperative participation of metal coordination, where internucleoside linkages are replaced by metal complexation motifs. The X-ray crystal structure and complexation behaviors of 3',5'-dithiothymidine, 1, with Au(I) are also reported. 相似文献