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11.
12.
V. V. Gusev V. I. Puzynin V. V. Kostrykin A. A. Kvitsinsky S. P. Merkuriev L. I. Ponomarev 《Few-Body Systems》1990,9(2-3):137-153
The adiabatic hyperspherical (AH) approach to the three-body Coulomb bound-state problems is considered. The variational method of computation of the AH harmonics potential curves and coupling matrix elements is developed. The method takes into account the asymptotic behaviour of the AH harmonics at large and small values of the hyperradius . The developed method allows to perform calculations with high accuracy and stability for any hyperradius (0,) with only a few AH harmonics. The efficiency of the method and its convergence is illustrated by calculations of energy levels of the mesic moleculesdd anddt. 相似文献
13.
14.
Gusev AI Wilkinson WR Proctor A Hercules DM 《Analytical and bioanalytical chemistry》1996,354(4):455-463
The protocol and various matrices were examined for quantification of biomolecules in both the low ca. 1200 amu and mid mass 6000-12000 amu ranges using an internal standard. Comparative studies of different matrices of MALDI quantitative analysis showed that the best accuracy and standard curve linearity were obtained for two matrices: (a) 2,5-dihydroxybenzoic acid (DHB) combined with a comatrix of fucose and 5-methoxysalicylic acid (MSA) and (b) ferulic acid/fucose. In the low mass range, the quantitative limit was in the 30 fmol range and in the mid mass range the quantitative limit was in the 250 fmol range. Linear response was observed over 2-3 decades of analyte concentration. The relative error of the standard curve slope was 1.3-1.8% with correlation coefficients of 0.996-0.998.The main problem for quantitative measurement was suppression of the signal of the less concentrated component (analyte or internal standard) by the more concentrated component. The effect was identified with saturation of the matrix by the analyte. The threshold of matrix saturation was found to be in the range of 1/(3000-5000) analyte/matrix molar ratio. To avoid matrix saturation the (analyte+internal standard) to matrix molar ratio should be below this threshold. Thus the internal standard concentration should be as low as possible.DHB/MSA/fucose and ferulic acid/fucose matrices demonstrated good accuracy and linearity for standard curves even when the internal standard had chemical properties different from the analyte. However, use of an internal standard with different chemical properties requires highly stable instrumental parameters as well as constant (analyte+internal standard)/matrix molar ratio for all samples. 相似文献
15.
N. A. Ustynyuk M. G. Peterleitner O. V. Gusev L. I. Denisovich 《Russian Chemical Bulletin》1993,42(10):1727-1730
The electrochemical behavior of rhodium sandwich complexes containing η4-pentamethylcyclopentadiene or tetramethylfulvene fragments has been studied by cyclic voltammetry. The complexes undergo
one-electron oxidation to give unstable 17-electron radical cations which are converted into rhodocenium salts as a result
of elimination or uptake of hydrogen or C-C bond cleavage.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1802–1805, October, 1993. 相似文献
16.
17.
V. P. Feshin M. Yu. Kon'shin A. V. Radushev E. V. Feshina V. Yu. Gusev A. E. Lesnov V. I. Karmanov 《Russian Chemical Bulletin》1996,45(11):2505-2508
The basicity of hydrazides of the highest aliphatic carboxylic acids RC(O)NHNH2 (R = CnH2n+1,n = 5-12) has been studied by potentiometric titration, and IR and1H NMR spectroscopy.Ab initio Hartree-Fork calculations using the 6–31G* basis set with full optimization of geometry were carried out on the simplest acy1hydrazines and their possible protonated forms. Based on these calculations, and the 1R and1H NMR spectra, the tautomerism of alkylhydrazides and the structures of their protonated forms are discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2645–2649, November, 1996. 相似文献
18.
1. | A method of the measurement of the acidity function H0 of sulfo cation exchangers was proposed. It was based on their absorption of an indicator base from an aqueous solution taking into account the activity coefficient of its unionized form (fB) in the phase of the sulfo cation exchanger. This is measured in an aqueous solution of p-toluenesulfonic acid with the same molar ratio of the sulfo groups to water as in the swollen sulfo cation exchanger. |
2. | The fB values of o-nitroaniline in aqueous solutions of p-toluenesulfonic acid (up to 53%) were measured at 25°C. |
3. | The H0 values of styrene-divinylbenzene sulfo cation exchangers of the gel type KRS-1, KRS-3, KRS-6, KRS-10, and KRS-12 and the large-pore types KU-23-15/100 and KU-23-30/ 100 were measured at 25°C. |
19.
G. A. Domrachev B. S. Kaverin E. G. Domracheva S. A. Gusev S. Yu. Ketkov V. L. Karnatsevich A. I. Kirillov I. L. Vasilevskaya M. A. Lopatin 《Russian Chemical Bulletin》1994,43(8):1305-1309
Hexagonal close-packed (HCP) C60 and C70 films have been prepared by the Langmuir method and examined by electron microscopy and electron-diffraction analysis. It has been shown that the vacuum deposition of a C60+C70 mixture results in the formation of a film with small sized grains and a distorted C60-HCP structure. The simultaneous deposition of C60 and ferrocene results in the formation of a film with a changed morphology and an electron-diffraction pattern that contains a variable amount of ferrocene depending on the experimental conditions. The electron-diffraction pattern corresponds to the presence of the known molecular complex C60[(C5H5)2Fe]2. The analogous simultaneous deposition of fullerene C60 and cobaltocene results in the formation of a C60 film stable in air and water, which contains carbon and cobalt (from the data of X-ray fluorescence, electron microscopy and microdiffraction). It has a different morphology and different diffraction patterns than pure C60 films and, depending on the cobaltocene content (relative to that of fullerene), appears to be a fullerite film doped with various amounts of cobaltocenium fullende, which is an ionic compound.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1379–1383, August, 1994.The work was financially supported by the Russian Foundation for Basic Research (Projects 93-03-4676 and 93-03-18368). 相似文献
20.
Abramov D. I. Bogdanova L. N. Gusev V. V. Ponomarev L. I. 《Hyperfine Interactions》1996,101(1):301-306
The sticking probabilities
Jv,G- and-factors for all bound states of mesic molecules ppµ, pdµ, ptµ, ddµ, dtµ, and ttµ withJ=0 andv=0, 1 have been calculated in the adiabatic hyperspherical approach (AHSA). 相似文献