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121.
El-Halawany AM Chung MH Ma CM Komatsu K Nishihara T Hattori M 《Chemical & pharmaceutical bulletin》2007,55(9):1332-1337
Through an anti-estrogenic bioassay-guided fractionation of the methanol extract of Mansonia gagei, three new coumarins, called mansorins I (1), II (2) and III (3) and a new naphthoquinone, mansonone I (4), were isolated. Their structures were determined based on their NMR data and CD spectroscopy. The anti-estrogenic activity of the fractions and the isolated compounds were investigated using a yeast two-hybrid assay method expressing estrogen receptors alpha (ERalpha) and beta (ERbeta). In addition, an ERalpha competitor screening system (ligand binding screen) was used to verify the binding affinities of the isolated compounds to the estrogen receptor. 1,2-Naphthoquinones (mansonones) showed more binding affinities to ER in both assay systems. All the tested compounds showed higher binding affinities to ERbeta than to ERalpha in the yeast two-hybrid assay. Mansonones F and S showed the most potent estrogen binding and estrogen antagonistic effects. 相似文献
122.
We consider a supersymmetric model in which gaugino masses are generated by the anomaly-mediation mechanism while scalar masses are from tree-level supergravity interaction. In such a model, scalar fermions as well as Higgsinos become as heavy as O(10–100 TeV) and hence only the gauginos are superparticles kinematically accessible to the LHC. We study how and how well the properties of gauginos can be studied. We also discuss the strategy to test the anomaly-mediation model at the LHC. 相似文献
123.
The arylation of dihydrosilanes with aryl iodides or heteroaryl iodides in the presence of a palladium catalyst provides the corresponding monohydrosilanes in good to high yield. Moderate to good yields are obtained even in the presence of a variety of reactive functional groups, such as -NH2, -OH, or -CN, without their protection. 相似文献
124.
Back Cover: Cycloparaphenylene‐Based Ionic Donor–Acceptor Supramolecule: Isolation and Characterization of Li+@C60⊂[10]CPP (Angew. Chem. Int. Ed. 12/2015) 下载免费PDF全文
125.
Inside Back Cover: Porous Carbon Fibers Containing Pores with Sizes Controlled at the Ångstrom Level by the Cavity Size of Pillar[6]arene (Angew. Chem. Int. Ed. 22/2015) 下载免费PDF全文
126.
Dr. Marian Olaru Dr. Julius F. Kögel Risa Aoki Prof. Dr. Ryota Sakamoto Prof. Dr. Hiroshi Nishihara Dr. Enno Lork Dr. Stefan Mebs Dr. Matthias Vogt Prof. Dr. Jens Beckmann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(1):275-284
The reaction of 2,6-F2C6H3SiMe3 with Ph2PLi provided 2,6-(Ph2P)2C6H3SiMe3 ( 1 ), which can be regarded as precursor for the novel anionic tridentate ligand [2,6-(Ph2P)2C6H3]− (PCP)−. The reaction of 1 with [AuCl(tht)] (tht=tetrahydrothiophene) afforded 2,6-(Ph2PAuCl)2C6H3SiMe3 ( 2 ). The subsequent reaction of 2 with CsF proceeded with elimination of Me3SiF and yielded the neutral tetranuclear complex linear-[Au4Cl2(PCP)2] ( 3 ) comprising a string-like arrangement of four Au atoms. Upon chloride abstraction from 3 with NaBArF4 (ArF=3,5-(CF3)2C6H3) in the presence of tht, the formation of the dicationic tetranuclear complex linear-[Au4(PCP)2(tht)2](BArF4)2 ( 4 ) was observed, in which the string-like structural motif is retained. Irradiation of 4 with UV light triggered a facile rearrangement in solution giving rise to the dicationic tetranuclear complex cyclo-[Au4(PCP)2(tht)2](BArF4) ( 5 ), which comprises a rhomboidal motif of four Au atoms. In 3 – 5 , the Au atoms are associated by a number of significant aurophilic interactions. The atom-economic and selective reaction of 3 with HgCl2 yielded the neutral trinuclear bimetallic complex [HgAu2Cl3(PCP)] ( 6 ) comprising significant metallophilic interactions between the Au and Hg atoms. Therefore, 6 may be also regarded as a metallopincer complex [ClHg(AuCAu)] between HgII and the anionic tridentate ligand [2,6-(Ph2PAuCl)2C6H3]− (AuCAu)− containing a central carbanionic binding site and two “gold-arms” contributing pincer-type chelation trough metallophilic interactions. Compounds 1 – 6 were characterized experimentally by multinuclear NMR spectroscopy and X-ray crystallography and computationally using a set of real-space bond indicators (RSBIs) derived from electron density (ED) methods including Atoms In Molecules (AIM), the Electron Localizability Indicator (ELI-D) as well as the Non-Covalent Interaction (NCI) Index. 相似文献
127.
β-1,3-Dicarbonyl aldehydes were synthesized by iron-catalyzed oxidative reactions between 1,3-dicarbonyl compounds and two molecules of tertiary amines in the presence of tert-butyl hydroperoxide (TBHP). α,β-Unsaturated aldehydes generated by tertiary amine oxidation in situ act as key intermediates under mild reaction conditions. 相似文献
128.
Kobayashi K Nishimura Y Gao F Gotoh K Nishihara Y Takagi K 《The Journal of organic chemistry》2011,76(6):1949-1952
Carbonylative homocoupling of arylzinc compounds 1 using 1 atm of CO and 1,2-dibromoethane as an oxidant was achieved in the presence of Rh-dppf catalyst, affording symmetrical diaryl ketones in good yields. Under similar conditions, Pd or Ni catalysts induced oxidative homocoupling of 1 to yield biaryls instead. The beneficial catalysis by Rh in the carbonylation was presumed to stem from the facility by which the migration of the aryl ligand to CO at the Rh(3+) intermediate occurred. 相似文献
129.
Kimichi Suzuki Masanori Tachikawa Hiroshi Ogawa Somlak Ittisanronnachai Hirotomo Nishihara Takashi Kyotani Umpei Nagashima 《Theoretical chemistry accounts》2011,130(4-6):1039-1042
To analyze the proton/deuteron (H/D) isotope effect on the stable adsorption sites on zeolite-templated carbon (ZTC), we have performed path integral molecular dynamics simulations including thermal and nuclear quantum effects with the semi-empirical PM3 potential at 300?K. Here, for the adsorption sites of additional proton (H*) and deuteron (D*), we chose different five carbon atoms labeled as ??-, ??1-, ??2-, ??-, and ??-carbons from edge to bottom for inside of buckybowl (C36H12 and C36D12). The stable adsorption sites of D* are observed on all carbon atoms, while those of H* are not observed on ??-carbon atom, but only on ??-, ??1-, ??2-, and ??-carbon atoms. This result is explained by the fact that H* can easily go over the barrier height for hydrogen transferring from ??- to ??2-carbons at 300?K, since the zero-point energy of H* is greater than that of D*. 相似文献
130.