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991.
Kota Omori Shunji Nagase Hajime Baba Kazuo Kodaira Takashi Abe 《Journal of fluorine chemistry》1977,9(4):279-291
The electrochemical fluorination of chlorine-containing alkylamines has been studied. It was found that, in general, the carbon-chlorine bond in the alkylamines is retained during electrochemical fluorination is anhydrous hydrogen fluoride, yielding chlorine-containing polyfluoroalkylamines. Perfluoroalkylamines and fluorocarbons were also produced.By the use of this method, several new chloropolyfluoroamines such as (CF3)2NCF2CClF2, (C2F5)2NCF2CClF2, (CF3)(C2F5)NCF2CClF2, (CClF2CF2)2NCF3, (CClF2CF2)2NC2F5, (C2F5)(CClF2CF2)NF, (CClF2CF2)2NF, (CF3)2NCF2CF2CClF2, CF2CClF2, and CF2CClF2 have been isolated and characterized. 相似文献
992.
Kazuo Nate Mitsuo Ishikawa Naoya Imamura Yoshihide Murakami 《Journal of polymer science. Part A, Polymer chemistry》1986,24(7):1551-1563
The synthesis and photochemical behavior of three types of polysiloxanes containing phenyldisilanyl units as chromophore have been reported. Irradiation of thin liquid films of the polymer (2) prepared from copolymerization of octamethylcyclotetrasiloxane and 1,3,5-triphenyl-1,3,5-tris(trimethylsilyl)cyclostrisiloxane (1) with a 500-W Xe-Hg lamp afforded transparent solid films which are insoluble in common organic solvents. Similar irradiation of thin liquid films of polysiloxane (8) containing both phenyldisilanyl units and vinyl groups resulted in formation of crosslinked solid films. When thick films of the polymers 2 and 8 were irradiated with a Xe-Hg lamp, crosslinking occurred only on the surface of the films, but inside remained as liquid. Irradiation of the films prepared from the polysiloxane involving the phenyldisilanyl units and butenyl groups, however, gave crosslinked solid films, whatever thickness of the films. The mechanism of photochemically induced crosslinking of the copolymers is discussed on the basis of the results obtained from the photolysis of 1,1-bis(trimethylsiloxy)-1-phenyl(trimethyl)disilane as a model compound. 相似文献
993.
Takata Y Matsubara H Kikuchi Y Ikeda N Matsuda T Takiue T Aratono M 《Langmuir : the ACS journal of surfaces and colloids》2005,21(19):8594-8596
The line tension of an air/hexadecane/aqueous solution of an dodecyltrimethylammonium bromide (DTAB) system was measured as a function of the molality of DTAB at 298.15 K by means of a newly constructed apparatus. It was estimated to be on the order of 10(-10)-10(-12) N, which is comparable to the theoretical estimation. Furthermore, its sign was reversed from positive to negative in the vicinity of the wetting transition concentration. The reversal of the sign was examined on the basis of our experimental findings on the wetting transition and the theory of Indekeu. 相似文献
994.
Takeshi Matsumoto Fuyuhiko Matsuda Kazuo Hasegawa Mitsutoshi Yanagiya 《Tetrahedron》1984,40(12):2337-2343
Synthesis of optically active pedamide (3), one of the tetrahydropyran moieties of the potent insect poison pederine (1), has been accomplished through a new, remote controlled asymmetric reduction of a ketone as key step. 相似文献
995.
Tetsuji Kametani Kazuo Kigasawa Mincharu Hiiragi Kikuo Wakisaka Nagatoshi Wagatsuma Osamu Kusama Tsunco Urya 《Journal of heterocyclic chemistry》1973,10(6):999-1005
1,2,3,4,5,6-Hexahydro-8-hydroxy-2,6-methano-3,6,1 1-trimethyl-2,3-benzo |g| diazocine (IV) and 1,2,3,4,5,10,11,12-octahydro-7-hydroxy-1,5-dimethylpyridazino |2,3-b| isoquinoline (VI) were synthesized from a common intermediate, 3-(3-methoxyphenyl)-2-butanone (VII), through several steps. Reaction of VII with ethyl bromoacetate gave the mixture of ethyl 4-keto-3-(3-methoxyphenyl)-3-methylpentanoate (XIV) and ethyl 4-keto-5-(3-methoxyphenyl)hexanoate (XV) which were hydrolyzed and condensed with methylhydrazine to give the 4,5-dihydro-5-(3-methoxyphenyl)-2,5,6-trimethyl- (XVIII) and 4,5-dihydro-6-(3-methoxy-α-methylbenzyl)-2-methylpyridazine-3(2H)one (XIX). Reduction of XVIII and XIX followed hy cyclization afforded the 2,3-benzo |g| diazocine (XXII) and the pyridazino |2,3-b| isoquinoline (XXIII) which on treatment with 47% hydrobromine acid afforded the phenolic bases (IV and VI), respectively. The mass spectrum of IV, VI, XXII and XXIII was also discussed. 相似文献
996.
A verdazyl derivative of benzo-15-crown-5 () has been prepared, and the complex formation between the spin labeled crown ether () and the alkali metal salts has been studied by ESR spectroscopy. 相似文献
997.
Kazuo Murato Bruno Frei Wolfhard Bernd Schweizer Hans Richard Wolf Oskar Jeger 《Helvetica chimica acta》1980,63(7):1856-1866
On triplet sensitization (E)- 5 gives (Z)- 5 and isomerizes via C(δ), O-bond cleavage to the cyclobutanone 6 and the conjugated γ-ketoester 7 . - On singulet excitation 6 undergoes decarbonylation and yields the bicyclo [4.1.0]heptane 8 . However, on triplet sensitization 6 is converted to the isomeric tricyclononane 9 by a stereospecific oxa-di-π-methane rearrangement. The structure of 9 is determined by X-ray analysis of the p-nitrobenzoate 15: a = 10.573, b = 14.707, c = 13.494 Å, β = 112.40°, P21/n, Z, = 4. 相似文献
998.
Kazuo Hara Yukio Imanishi Toshinobu Higashimura Mikiharu Kamachi 《Journal of polymer science. Part A, Polymer chemistry》1971,9(10):2933-2948
1-Vinylcyclohexene (VCH), which has one of the double bonds in the ring and the other outside the ring, was synthesized and polymerized by cationic catalysts. The reactivity of VCH was very large in the polymerizations catalyzed by boron trifluoride etherate (BF3OEt2) and stannic chloride–trichloroacetic acid complex. Similar to other cyclic dienes, the polymerization of VCH was a nonstationary reaction having a very fast initiation step. The polymerization proceeded by either a 1,2- or a 1,4-propagation mode in which vinyl group was always involved. Particularly when BF3OEt2 was used as a catalyst, an intramolecular proton or an intramolecular hydride ion transfer reaction took place, resulting in the formation of methyl groups in the polymer. The degree of polymerization of polymer formed was about 10. This indicates the preponderance of monomer transfer reaction. To investigate the reason for the high reactivity of cyclic dienes, cationic copolymerizations of VCH and 3-methyl-cis/trans-1,3-pentadiene (cis/trans-MPD) was carried out. The relative reactivity of monomers decreased in the order VCH > trans-MPD > cis-MPD. On the other hand, the resonance stabilization of monomers decreased in the order VCH > trans-MPD > cis-MPD. Therefore, it could be considered that the monomer reactivity is mainly determined by the stability of carbonium ion intermediate. The relative stability of carbonium ion must be VCH > trans-MPD > cis-MPD. Thus the influence of the conformation of ion on its stability was clearly demonstrated. 相似文献
999.
Kazuo Soga Yoshiji Takano Shigeo Go Tominaga Keii 《Journal of polymer science. Part A, Polymer chemistry》1967,5(11):2815-2823
The influence of SeOCl2 on the polymerization of propylene by TiCl3–Al(C2H5)3, and the temperature dependence of the stereospecificity of the catalyst, TiCl3–Al(C2H5)3, have been investigated. SeOCl2 decreases the rate of polymerization and increase the stereospecificity of the catalyst, which could be explained on the basis of a decrease of the concentration of Al(C2H5)3 accompanied by a reaction between Al(C2H5)3 and SeOCl2. On the other hand, the stereospecificity of the catalyst, TiCl3–Al(C2H5)3, increases gradually with a decrease in polymerization temperature from 40 to 0°C. From these results, we conclude that SeOCl2 exerts no essential influence on the polymerization of propylene by TiCl3–Al(C2H5)3, and that the stereospecificity of the catalyst is attributed mainly to the reducing ability of the organometallic compound. 相似文献
1000.
Motokazu Uemura Kazuhiko Take Kazuo Isobe Tatsuya Minami Yuji Hayashi 《Tetrahedron》1985,41(24):5771-5778
(3-Methoxybenzylalcohol)chromium tricarbonyl (10) and (7-methoxy-1-tetralol)chromium tricarbonyl (12) are selectively lithiated at the 4- and 6-positions, respectively, by treatment with n-BuLi-TMEDA. Since the directed lithiation of the corresponding chromium free arenes normally proceeds at the 2-and 8-positions, complementarily substituted arenes can be prepared by using the chromium tricarbonyl complexes. The difierent position of lithiation is explained by the relative configuration of the chromium tricarbonyl group in the (arene)Cr(CO)3 and electrostatic factors. Some anthraquinones, 31,36,42, and 7-hydroxycalamenenes, 43, have been synthesized through the stereo- and regioselective introduction of substituents by means of(η6-arene)chromium tricarbonyl complexes. 相似文献