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991.
Horike S Kishida K Watanabe Y Inubushi Y Umeyama D Sugimoto M Fukushima T Inukai M Kitagawa S 《Journal of the American Chemical Society》2012,134(24):9852-9855
We elucidated the specific adsorption property of CO(2) for a densely interpenetrated coordination polymer which was a nonporous structure and observed gas separation properties of CO(2) over CH(4), C(2)H(4), and C(2)H(6), studied under both equilibrium and kinetic conditions of gases at ambient temperature and pressure. 相似文献
992.
T Kusakabe K Kawaguchi M Kawamura N Niimura R Shen H Takayama K Kato 《Molecules (Basel, Switzerland)》2012,17(8):9220-9230
The cyclization-carbonylation-cyclization coupling reaction (CCC-coupling reaction) of propargyl ureas catalyzed by PdII(box) complexes afforded symmetrical ketones bearing two 2-amino-2-oxazoline groups in good to moderate yields. 相似文献
993.
Ohyoshi T Funakubo S Miyazawa Y Niida K Hayakawa I Kigoshi H 《Angewandte Chemie (International ed. in English)》2012,51(20):4972-4975
Ring functionalization: the total synthesis of a natural derivative of (-)-13-oxyingenol, a potent anti-HIV diterpenoid, is reported. The key steps in this synthesis include a ring-closing olefin metathesis and a Mislow-Evans-type [2,3]-sigmatropic rearrangement. This synthesis provides access to (-)-13-oxyingenol and its natural derivative in 21 steps from a synthetic intermediate previously prepared by Kigoshi and co-workers. 相似文献
994.
O- or N-protonated? The bis(μ-hydroxo)divanadium(IV)-substituted γ-Keggin-type polyoxometalate (see picture, left) (TBA)(4)[γ-SiV(IV)(2)W(10)O(36)(μ-OH)(4)] (TBA = tetra(n-butyl)ammonium) was synthesized and characterized by X-ray crystallography. Its reaction with phenyl isocyanate gave (TBA)(4)[γ-SiV(IV)(2)W(10)O(38)(μ-OH)(2)(PhNHCO)(2)], which contains two N-protonated phenyl isocyanate species and catalyzes the cyclotrimerization of phenyl isocyanate. 相似文献
995.
Hamura T Chuda Y Nakatsuji Y Suzuki K 《Angewandte Chemie (International ed. in English)》2012,51(14):3368-3372
A fair exchange: In the title reaction, alkynyllithium serves as an initiator for benzyne generation through an iodine-lithium exchange (see scheme; Tf=trifluoromethanesulfonyl). When performed in the presence of stoichiometric amounts of a nucleophile, the generated benzyne undergoes attack by lithio nucleophiles to generate aryllithium, which is then iodinated by iodoalkyne to give the iodoarenes 1. 相似文献
996.
Gokulnath S Toganoh M Yamaguchi K Mori S Uno H Furuta H 《Dalton transactions (Cambridge, England : 2003)》2012,41(20):6283-6290
Singly N-confused [26] and [28]hexaphyrins (4, 5) with planar and twisted structures, respectively, were prepared via the acid catalyzed [3 + 3] condensation of N-confused and regular tripyrrane precursors. Hückel aromaticity is observed for [26]hexaphyrin, while the [28]hexaphyrin and its mono-Pd(II) complex exhibit "nonaromaticity" in spite of their M?bius-type structures, judging from the spectroscopic features and theoretical calculations. 相似文献
997.
Fusano A Sumino S Nishitani S Inouye T Morimoto K Fukuyama T Ryu I 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(30):9415-9422
The atom-transfer carbonylation reaction of various alkyl iodides thereby leading to carboxylic acid esters was effectively accelerated by the addition of transition-metal catalysts under photoirradiation conditions. By using a combined Pd/hν reaction system, vicinal C-functionalization of alkenes was attained in which α-substituted iodoalkanes, alkenes, carbon monoxide, and alcohols were coupled to give functionalized esters. When alkenyl alcohols were used as acceptor alkenes, three-component coupling reactions, which were accompanied by intramolecular esterification, proceeded to give lactones. Pd-dimer complex [Pd(2)(CNMe)(6)][PF(6)](2), which is known to undergo homolysis under photoirradiation conditions, worked quite well as a catalyst in these three- or four-component coupling reactions. In this metal/radical hybrid system, both Pd radicals and acyl radicals are key players and a stereochemical study confirmed the carbonylation step proceeded through a radical carbonylation mechanism. 相似文献
998.
Prof. Dr. Shiki Yagai Keisuke Ohta Marina Gushiken Kazunori Iwai Atsushi Asano Prof. Dr. Shu Seki Dr. Yoshihiro Kikkawa Prof. Dr. Masakazu Morimoto Prof. Dr. Akihide Kitamura Prof. Dr. Takashi Karatsu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(8):2244-2253
Diarylethene 1 equipped with two monotopic melamine hydrogen‐bonding sites and oligothiophene‐functionalized ditopic cyanurate (OTCA) were mixed in a nonpolar solvent to form AA‐BB‐type supramolecular co‐polymers (SCPs) bearing photoswitchable moieties in their main chains and extended π systems as side chains. UV/Vis, fluorescence, dynamic light scattering (DLS), TEM, and AFM studies revealed that the two functional co‐monomers formed flexible quasi‐one‐dimensional SCPs in solution that hierarchically self‐organized into helical nanofibers through H‐aggregation of the oligothiophene side chains. Upon irradiating the SCPs with UV light, a transition occurred from the H‐aggregated state to non‐aggregated monomeric oligothiophene side chains, as shown by spectroscopic studies, which indicates the formation of small oligomeric species held together only by hydrogen‐bonding interactions. TEM and AFM visualized unfolded fibrils corresponding to elongated single SCP chains formed upon removal of solvent. The helical nanofibers were regenerated upon irradiating the UVirradiated solution with visible light. These results demonstrated that the supramolecular polymerisation followed by hierarchical organization can be effectively controlled by proper supramolecular designs using diarylethenes and π‐conjugated oligomers. 相似文献
999.
Synthesis and application of poly(fluorene-alt-naphthalene diimide) as an n-type polymer for all-polymer solar cells 总被引:1,自引:0,他引:1
Zhou E Cong J Zhao M Zhang L Hashimoto K Tajima K 《Chemical communications (Cambridge, England)》2012,48(43):5283-5285
A new alternating copolymer of fluorene and naphthalene diimide, PF-NDI, was synthesized and characterized. The highest power conversion efficiency of all-polymer solar cells based on P3HT:PF-NDI reached 1.63% with a relatively high fill factor of 0.66 by using 1,8-diiodooctane as a solvent additive to optimize the mixing morphology. 相似文献
1000.
Fujihara T Nogi K Xu T Terao J Tsuji Y 《Journal of the American Chemical Society》2012,134(22):9106-9109
Nickel-catalyzed carboxylation of aryl and vinyl chlorides employing carbon dioxide has been developed. The reactions proceeded under a CO(2) pressure of 1 atm at room temperature in the presence of nickel catalysts and Mn powder as a reducing agent. Various aryl chlorides could be converted to the corresponding carboxylic acid in good to high yields. Furthermore, vinyl chlorides were successfully carboxylated with CO(2). Mechanistic study suggests that Ni(I) species is involved in the catalytic cycle. 相似文献