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111.
G. A. Kozlov 《Theoretical and Experimental Chemistry》1989,25(2):214-216
ESR has been applied to the interactions of [K(DBC)]3[Co(CN)5], in which DBC is dibenzo-18-crown-6, in methanol solution with triphenylphosphine, pyridine, and triethylamine. The ESR spectra are described for the paramagnetic [(NC)5CoB]3– adducts, where B is triphenylphosphine or pyridine.Translated from Teoreticheskaya i Éxperimental'naya Khimiya, Vol. 25, No. 2, pp. 234–237, March–April, 1989. 相似文献
112.
Roman Mazurkiewicz 《Monatshefte für Chemie / Chemical Monthly》1989,120(11):973-980
Summary N-Acylanthranilamides react with dibromotriphenylphosphorane in the presence of triethylamine as HBr captor to give 4-imino-4H-3,1-benzoxazines in good yields. If the reaction is carried out without acid acceptor, N-acetylanthranilamides yield 2-methyl-4-quinazolones, whereas N-benzoylanthranilamides give 2-phenyl-4-imino-4H-3,1-benzoxazines. It has also been found that 2-methyl-4-imino-4H-3,1-benzoxazines rearrange under the influence of HCl or HBr into the respective 2-methyl-4-quinazolones; 2-phenyl-4-imino-4H-3,1-benzoxazines, however, do not undergo such a rearrangement.
Synthese und Umlagerung von 4-Imino-4H-3,1-benzoxazinen
Zusammenfassung Die Umsetzung von N-Acyl-anthranilsäure-amiden mit Triphenyldibromphosphoran in Gegenwart von Triethylamin als HBr-Akzeptor führt mit guten Ausbeuten zu 4-Imino-4H-3,1-benzoxazinen. Wird die Reaktion ohne säurebindendes Mittel durchgeführt, dann entstehen aus N-Acetyl-anthranilsäure-amiden 2-Methylchinazolone-4, jedoch erhält man aus N-Benzoylanthranilsäure-amiden 2-Phenyl-4-imino-4H-3,1-benzoxazine. 2-Methyl-4-imino-4H-3,1-benzoxazine erleiden unter dem Einfluß von HBr oder HCl eine Umlagerung in entsprechende 2-Methylchinazolone-4, während 2-Phenyl-4-imino-4H-3,1-benzoxazine zu einer solchen Umlagerung nicht befähigt sind.相似文献
113.
Koval'skaya S. S. Kozlov N. G. Dikusar E. A. 《Russian Journal of Organic Chemistry》2004,40(5):668-674
Reaction of 2-(3-hydroxy-3-methyl-1-butynyl)adamantan-2-ol with acetonitrile under Ritter reaction conditions is accompanied by isomerization and partial hydration where the water addition to the triple bond occurs nonselectively. As a result of reaction carried out in the presence of 8 equiv of sulfuric acid a mixture was obtained of N
2-[4-(1-acetylamino-2-adamantyl)-2-methyl-3-butyn-2-yl]acetamide, N
3-[1-(1-acetylamino-2-adamantyl)-3-methyl-2-oxo-3-butyl]-acetamide, and N
3-[1-(1-acetylamino-2-adamantyl)-3-methyl-1-oxo-3-butyl]acetamide in ~10:3:2 ratio. In the presence of 2 equiv of the acid the mixture obtained consisted of N
2-[4-(1-acetylamino-2-adamantyl)-2-methyl-3-butyn-2-yl]acetamide, N
3-[1-(1-acetylamino-2-adamantyl)-3-methyl-2-oxo-3-butyl]acetamide, and 1-(1-acetylamino-2-adamantyl)-3-methyl-2-buten-1-one in the same ratio. In Rupe reaction conditions we obtained instead of the expected ,-unsaturated ketones a mixture of 1-(1-hydroxy-2-adamantyl)-3-hydroxy-3-methylbutan-1-one and 1-(1-hydroxy-2-adamantyl)-3-hydroxy-3-methylbutan-2-one in a 5:3 ratio. 相似文献
114.
Abstract— The UV spectra of solid amorphous films of all-trans retinyl polyenes. i. e. retinyl acetate, retinyl palmitate, axerophtene and retinal, on supports are investigated. It is shown that in the absence of oxygen the spectra of the films do not change at room temperature; in the presence of O2 the fast oxidation of the polyenes occurs which in the case of retinol esters and axerophtene is accompanied by the shift of the absorption maxima to the shorter wavelengths. Consequently, the interpretation of blue shift of UV spectra of retinyl polyene films given by Hotchandani and Leblanc (1976) is incorrect. The formation of the only compound is shown to occur during the first stage of the oxidation of retinyl acetate and retinyl palmitate films. Proceeding from IR spectra of oxidized films the compound is assigned to the corresponding 11-cis isomer. 相似文献
115.
Roman Pogreb Oleg Popov Vlad Lirtsman Oleg Pyshkin Alexander Kazachkov Albina Musin Gene Whyman Binyamin Finkelshtein Yuri Shmukler Dan Davidov Alexander Gladkikh Edward Bormashenko 《先进技术聚合物》2006,17(1):20-25
The work is devoted to luminescent properties of trivalent lanthanide complexes dispersed in thermoplastic host matrices. Polyethylene films and polypropylene‐rods, both doped with these complexes, were manufactured using an extrusion technique. Two kinds of dopants were used: Eu(III)‐thenoyltrifluoroacetone‐1,10‐phenanthroline complex (1) and Eu(III)‐La(III)‐1,10‐phenanthroline complex (2). Absorption, excitation, emission spectra and lifetime of luminescence were studied. The impact of the polymer matrix on the emission spectra was investigated. Emission spectra of the films were studied at room and helium temperatures. Time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) surface mapping showed that in the Eu(III)‐La(III) complex europium forms islands (clusters) with a dimension of 1 µm, whereas lanthanum was dispersed more uniformly in the polymer matrix. Dependence of emission intensity on the excitation was determined. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
116.
Roman Boča 《Theoretical chemistry accounts》1982,61(2):179-192
The perturbative configuration interaction using localized orbitals (the PCILO method) was extended in the way that current limitations to the two-centre bond approach were overcome. The localized molecular orbitals contain an arbitrary number of the basis set components; this follows from the a priori stated localized bonding model of a molecule. The extended PCILO method was formulated for the CNDO, INDO and NDDO Hamiltonian approximations. The configuration interaction was performed using the Rayleigh-Schrödinger many-body perturbation theory with the Møller-Plesset type of Hamiltonian partitioning, similar to that used in the so-called modified PCILO method. Applications to molecules with semi-localized and/or semi-delocalized bonds, as benzene or diborane, are presented. 相似文献
117.
Calculations are made of the ordering energyV (R) and the Fourier transform v() of it for the disordered Cu3Au alloy in the Fermi sphere approximation using the pseudopotential method in the second order of perturbation theory. These characteristics are used to calculate some properties of the alloy, in particular, the short- and long-range order and the temperature of the order-disorder transition.Translated from Izvestiya Vysshikh Zavedenii, Fizika, No. 10, pp. 84–88, October, 1980. 相似文献
118.
The charging of an illuminated silicon surface discovered by Abkevich [1] is of considerable interest for a number of practical applications (for example, semiconductor photography [2] and gas analysis). The present paper gives the results of investigations aimed at establishing the possibility of controlling the optical charge memory on the silicon surface by adsorption methods.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 92–96, January, 1981.We thank V. F. Kiselev for discussing the work and for helpful comments. 相似文献
119.
Silicon-silicon dioxide structures obtained by thermal, anodic, and chemical oxidation of silicon are studied by the photocharge and photoinjection current methods. It is shown that the extent of the fluctuation state tails" near the edges of the SiO2 forbidden zone is small (0.2 eV). The threshold for negative photocharging of anodic oxide traps is found to decrease with increase in oxide thickness, a fact related to the existence of a nonstoichiometric transition layer between the silicon and silicon dioxide. The effect of hydration and dehydration on negative optical charge of oxide traps is studied, and it is shown that the basis of electron traps is formed by the most hydrated and deformed SiO4Hn tetrahedra. The possibility of creating electron and hole traps in the oxide layer by doping with metal ions from a solution is demonstrated. It is found that the corresponding defects are also adsorption centers for water molecules by a coordination mechanism.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 3–7, July, 1981.In conclusion, the authors thank V. F. Kiselev for his interest in the study and valuable remarks. 相似文献
120.
Christine GozeDenis V. Kozlov Felix N. CastellanoRaymond Ziessel 《Tetrahedron letters》2003,44(48):8713-8716
The synthesis of novel ruthenium(II) bipyridine or terpyridine complexes bearing an increasing number of pyrene or toluyl moieties is described. The ruthenium complexes are constructed in a first step with ligands bearing the required bromine functions, followed in a second step by stepwise grafting of 1-ethynylpyrene or 4-ethynyltoluene promoted by Pd(0). A complex bearing a protected triethylsilylacetylene function was also prepared. In situ deprotection of this function with K2CO3 and cross-coupling with 1-bromopyrene afforded a soluble complex in which two pyrene moieties are linearly linked via ethynyl spacers to one of the bipyridine ligands. These highly coloured complexes exhibit well defined absorption and emission properties in solution at both rt and 77 K. 相似文献