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1.
The spectrum and the spatial distribution of the emission of scattered particles upon bombardment of Be, Ti, Ta, and W with H and He ions were studied. The quantum yield and the velocity and angular distributions of the scattered excited particles were measured. Computer simulation of the scattering of H ions and He ions from the metals under study was performed with the use of the program TRIM-95. Agreement is observed between the calculated and experimentally measured angular distributions of the scattered particles. 相似文献
2.
V. T. Kalinnikov Zh. A. Ezhova N. A. Zakharov E. M. Koval’ 《Russian Journal of Inorganic Chemistry》2007,52(1):112-115
The CaCl2-(NH4)2HPO4-NH2(CH2)4NH2CHCOOH-NH3-H2O system at 25°C is studied using Tananaev’s solubility (residual concentrations) method and pH measurements. Lysine-containing calcium hydroxylapatite Ca10(PO4)6(OH)1.9[NH2(CH2)4NH2CHCOO]0.1 · 6H2O is identified using chemical analysis, thermogravimetry, powder X-ray diffraction, and IR spectroscopy. 相似文献
3.
A new preparative method of synthesis was developed for unsymmetrical, symmetricaldisulfides consisting in sulfenylation of sodium thiolates with N-arenesulfenyl-N,N'-bis(arenesulfonyl)sulfin-amidines. Imination of unsymmetrical disulfides with sodium chloroamides of sulfonic acids occurs at the more nucleophilic sulfur atom affording N,N'-bis(arenesulfonyl)sulfinamidines and symmetrical disulfides. 相似文献
4.
E. A. Belousova V. V. Koval N. I. Rechkunova S. Kh. Degtyarev O. S. Fedorova O. I. Lavrik 《Russian Chemical Bulletin》2005,54(5):1306-1310
The interaction of DNA polymerase Tte from Thermus thermophilus B35 with dUTP analog containing a fluorescein residue bound to C(5) of the base (Flu-dUTP) was studied by fluorescence titration.
The dissociation constants of the enzyme—substrate complexes in the absence and in the presence of a DNA duplex containing
an extended template and bivalent metal ions and the kinetic parameters of polymerization by DNA polymerase Tte in the presence of Flu-dUTP were determined.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1268–1272, May, 2005. 相似文献
5.
The molecular structures of 1,3-benzodioxole and 1,3-indandione partially oriented in nematic solvents have been studied by NMR. Results for 1,3-indandione agree well with a planar model. The structural parameters are similar to those obtained by X-ray studies. No keto-enol tautomerism is observed. An anomalous structural result is obtained for 1,3-benzodioxole if the molecule is assumed to be planar. Dipolar couplings agree well with puckered model. The puckering angle is found to be about 15.5° ± 2°, similar to the values observed for TTF, TSeF and 2,5-dihydrofuran. 相似文献
6.
N. V. Stratan E. P. Koval’chuk J. Blazejowski 《Russian Journal of General Chemistry》2004,74(12):1900-1906
In terms of the ability for electrochemical transformations in acidic medium, the reactivity decreases in the order o-aminoacetophenone > p-aminoacetophenone > m-aminoacetophenone > aniline. The products of electrochemical polycondensation of the ortho and para isomers are conductors. Oxidative polycondensation of o-aminoacetophenone forms emeraldin hydrosulfate, and with p- and m-aminoacetophenones, emeraldin and leucoemeraldin are formed. In terms of thermal stability, polyacetoaminophenones can be ranked in the order poly-o-aminoacetophenone > poly-m-aminoacetophenone > poly-p-aminoacetophenone.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 12, 2004, pp. 2012–2018.Original Russian Text Copyright © 2004 by Stratan, Kovalchuk, Blazejowski.This revised version was published online in April 2005 with a corrected cover date. 相似文献
7.
V. Brabec M. Ryšavý O. Dragoun M. Fišer A. Kovalík Cs. Ujhelyi D. Berényi 《Zeitschrift für Physik A Hadrons and Nuclei》1982,306(4):347-351
The relative conversion line intensities of the 35 keV transition in125Te were measured using the 50 cm π√2 iron-yoke magnetic spectrometer. The transition was proved to be ofM1+(8.7±1.5)×10?4 E2 multipolarity, the magnetic component being affected by the nuclear structure with λ=2.4±1.4. The conversion intensity ratio,0/N 1 , was determined to be 0.115+0.005 for both Ag125 I and Cu125 I sources. It is in accordance with previous measurements for the Zn125m Te and Pb125m Te sources and differs from those for the125mTeO2 and Na2H 4 125m TeO6 ones. The conversion coefficients were calculated for 32 configurations of the valence shell of free tellurium atom and ions and were compared with the experimental results. 相似文献
8.
Novikova N. N. Yakunin S. N. Koval’chuk M. V. Yur’eva E. A. Stepina N. D. Rogachev A. V. Kremennaya M. A. Yalovega G. E. Kosmachevskaya O. V. Topunov A. F. 《Crystallography Reports》2019,64(6):952-957
Crystallography Reports - XANES spectra of protein films (hemoglobin and alkaline phosphatase) formed on the surface of a liquid subphase in a Langmuir trough have been obtained experimentally. The... 相似文献
9.
Radiophysics and Quantum Electronics - The Wigner and Kirkwood functions are widely used for signal processing. We review their properties and representations. The Wigner function calculation... 相似文献
10.
Zh. A. Ezhova N. A. Zakharov E. M. Koval’ N. T. Kuznetsov 《Russian Journal of Inorganic Chemistry》2018,63(8):1001-1006
Nanocomposites (NCs) based on carbonated calcium hydroxyapatite (CHA) (bioapatite, an analogue of the inorganic component of mammalian bone tissue), carbonate apatite (Ca10(PO4)6CO3, CA), and multiwall carbon nanotubes (CNTs) are prepared in the system CaCl2–(NH4)2HPO4–NH4HCO3–NH3–CNT–H2O (25°C) by coprecipitation of calcium and phosphorus salts with CNTs from aqueous solutions. The physicochemical properties of nanocomposites are studied as dependent on their formation conditions and composition using the solubility (residual concentrations) method and pH measurements. The composition, crystal structure, morphology, spectroscopic and thermal characteristics of the synthesized CHA/CNT and CA/CNT NCs are determined using chemical analysis, X-ray powder diffraction, thermal analysis, and IR spectroscopy. Either CHA/CNT NCs of composition Ca10(PO4)6(CO3)x(OH)2–2х · yCNT · zH2O, where х = 0.2; 0.5; 0.8; y = 1, 2, 3; z = 6.8–10.8, or (when х = 1) CA/CNT NCs of composition Ca10(PO4)6CO3 · yCNT · zH2O, where y = 1–3; z = 6.9–10.8, are formed as the carbonate and CNT contents of the NC increase. Our results favor the understanding of the effect of carbonization and CNTs on the metabolic formation of native bone tissue apatite and can be used for the design of efficient ceramics for bone implants. 相似文献