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11.
Di Li Naoki Ohashi Shunichi Hishita Taras Kolodiazhnyi Hajime Haneda 《Journal of solid state chemistry》2005,178(11):3293-3302
An overall comparative study was carried out on N-doped, F-doped, and N-F-codoped TiO2 powders (NTO, FTO, NFTO) synthesized by spray pyrolysis in order to elucidate the origin of their visible-light-driven photocatalysis. The comparisons in their experimentally obtained characteristics were based on the analysis of XPS, UV-Vis, PL, NH3-TPD and ESR spectra. The comparisons in their theoretically predicted properties were based on the analysis of the calculated electronic structures. As the results, N-doping into TiO2 resulted in not only the improvement in visible-light absorption but also the creation of surface oxygen vacancies. F-doping produced several beneficial effects including the creation of surface oxygen vacancies, the enhancement of surface acidity and the increase of Ti3+ ions. Doped N atoms formed a localized energy state above the valence band of TiO2, whereas doped F atoms themselves had no influence on the band structure. The photocatalytic tests indicated that the NFTO demonstrated the highest visible-light activity for decompositions of both acetaldehyde and trichloroethylene. This high activity was ascribed to a synergetic consequence of several beneficial effects induced by the N-F-codoping. 相似文献
12.
Petrenko P. A. Gdaniec M. Simonov Yu. A. Stavila V. G. Gulea A. P. 《Russian Journal of Coordination Chemistry》2004,30(11):813-817
A Ni(II) complex of the composition Ni(HNta) · 4H2O (I) was synthesized. Its structure was found to consist of neutral mononuclear [Ni(HNta)(H2O)3] complexes and crystallization water molecules. The Ni atom has octahedral surrounding and is coordinated to tridentate-chelate HNta2– ligand through the N atom and O atoms of two deprotonated acetate groups and through the O atoms of three water molecules. The structure of I was compared with those of the Zn(HNta) · 4H2O and Co(HNta) · 4H2O complexes isostructural to I. Thermogravimetric method showed that the decomposition of compound I occurs through several successive stages of dehydration, deaquation, decarboxylation, and the formation of inorganic residue. 相似文献
13.
The induction of single-strand breaks (SSB) by two quantum processes in DNA is well established. We now report that biphotonic processes result in double-strand breaks (DSB) as well. pUC19 and bacteriophage M13 RF DNA were irradiated using an excimer laser (248 nm) at intensities of 10(7), 10(9), 10(10) and 10(11) W/m2 and doses up to 30 kJ/m2. The proportion of DNA as supercoil, open circular, linear and short fragments was determined by gel electrophoresis. Linear molecules were noted at fluences where supercoiled DNA was still present. The random occurrence of independent SSB in proximity to each other on opposite strands (producing linear DNA) implies introduction of numerous SSB per molecule in the sample. If so, supercoiled DNA that has sustained no SSB should not be observed. A model accounting for the amounts of supercoiled, open circular, linear and shorter fragments of DNA due to SSB, DSB and Scissions (opposition of two independently occurring SSB producing an apparent DSB) was developed, our experimental data and those of others were fit to the model, and quantum yields determined for SSB and DSB formation at each intensity. Results showed that high intensity laser radiation caused an increase in the quantum yields for both SSB and DSB formation. The mechanism of DSB formation is unknown, and may be due to simultaneous cleavage of both strands in one biphotonic event or the biased introduction of an SSB opposite a preexisting SSB, requiring two biphotonic events. 相似文献
14.
V. V. Lapachev O. A. Zagulyaeva O. P. Petrenko S. F. Bychkov V. P. Mamaev 《Chemistry of Heterocyclic Compounds》1984,20(6):676-680
The existence of a pyrimidinyl-pyrimidinylidene tautomeric equilibrium in solutions of 2-pyrimidinylcyanoacetic acid esters in CDCl3 was observed. Unsymmetrically substituted compounds form two types of ylidene tautomers that differ with respect to the position of the NH proton, the ratio between which is controlled by the substituents in the 4 (6) position. The introduction of both donor and acceptor substituents into the 5 position of the pyrimidine ring increases the amount of the pyrimidine form. The same thing occurs when the polarity of the solvent is decreased. The addition of DMSO or DMF to CDCl3 leads to conversion of the intrachelate ylidene tautomers to unchelated tautomers. Protonation (CF3COOH) shifts the equilibrium to favor the ylidene tautomer that has higher basicity.See [1] for communication 5.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 827–831, June, 1984. 相似文献
15.
K. B. Petrenko 《Journal of Mathematical Sciences》1992,61(2):2044-2045
The result of the note consists in the fact that the Radon—Nikodym property (see A. V. Bukhvalov, Zap. Nauchn. Sem. LOMI, Vol. 65, pp. 5–16, 1976) corresponds to the boundary behavior of functions from the vector-valued Hardy classes HP(Dn, X) and not only to those from the one-dimensional classes HP(D, X).Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akademii Nauk SSSR, Vol. 178, pp. 163–165, 1989. 相似文献
16.
T. I. Emets M. V. Steblyuk N. A. Klyuev V. V. Petrenko 《Chemistry of Natural Compounds》1995,30(3):292-294
The lipid composition of the free fatty acids of the seed oil ofMalva sylvestris from the Ukrainian flora has been studied by chromato-mass spectrometry. The fatty acid composition was represented by 20 compounds, among which malvic and sterculic acids were detected. The presence of terpineols and retinol has been shown.Zaporozh'e Medical Institute. Translated from Khimiya Prirodnykh Soedenii, No. 3, pp. 322–325, May–June, 1994. 相似文献
17.
18.
M. L. Antipova D. L. Gurina V. E. Petrenko 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2014,88(2):259-266
Hydrogen-bonded clusters and solvate structures formed by o-hydroxybenzoic acid (o-HBA) and water in supercritical CO2 were studied (T = 318 K, 348 K, ρ = 0.7 g/cm3). The atom-atom radial distribution functions, coordination numbers, average numbers of hydrogen bonds for individual atomic groups, and power spectrum were calculated by the Car-Parrinello molecular dynamics. Despite the high polarity of the cosolvent, the hydroxyl group of o-HBA predominantly forms intramolecular hydrogen bond, while hydrogen bonds with water involve only the atoms of carboxyl groups. The temperature effect on the stability of these bonds showed itself in different ways. The intermolecular interactions of o-HBA with carbon dioxide were found to be weaker than those with water. It was established that the Lewis acid-Lewis base interactions between CO2 and the hydroxyl group of the solute increase with increasing temperature. Instantaneous configurations illustrating the temperature effects on the molecular structures were obtained. 相似文献
19.
Petrenko D. E. Nikolaeva A. Yu. Lazarenko V. A. Dorovatovskii P. V. Timofeev V. I. Vlaskina A. V. Korzhenevskiy D. A. Mikhailova A. G. Rakitina T. V. 《Crystallography Reports》2020,65(2):264-268
Crystallography Reports - Oligopeptidases B (OpdBs) are two-domain serine peptidases with trypsin-like substrate specificity belonging to the prolyl oligopeptidase family. These enzymes are... 相似文献
20.
D. L. Gurina V. E. Petrenko M. L. Antipova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(7):1138-1144
Radial distribution functions and the average number of hydrogen bonds per methanol molecule under standard, subcritical, and supercritical conditions are obtained via classical molecular dynamics and Car-Parrinello nonempirical molecular dynamics. It is shown that independent methods of modeling yield close results. It is noted that the calculated radial distribution functions agree well with the experimental data only at T = 298 K and P = 0.1 MPa, while at high temperatures and pressures, considerable divergence from the experimental functions known from the literature is observed. It is concluded that both modeling methods reproduce the degree of hydrogen bonding in methanol and its variations depending on the state parameters and correspond closely to the experimental results. 相似文献