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81.
Xiaoyi Wang Mark D. Wilkinson Xiaoyan Lin Ren Ren Keith R. Willison Aleksandar P. Ivanov Jake Baum Joshua B. Edel 《Chemical science》2020,11(4):970
Actin is a key protein in the dynamic processes within the eukaryotic cell. To date, methods exploring the molecular state of actin are limited to insights gained from structural approaches, providing a snapshot of protein folding, or methods that require chemical modifications compromising actin monomer thermostability. Nanopore sensing permits label-free investigation of native proteins and is ideally suited to study proteins such as actin that require specialised buffers and cofactors. Using nanopores, we determined the state of actin at the macromolecular level (filamentous or globular) and in its monomeric form bound to inhibitors. We revealed urea-dependent and voltage-dependent transitional states and observed the unfolding process within which sub-populations of transient actin oligomers are visible. We detected, in real-time, filament-growth, and drug-binding at the single-molecule level demonstrating the promise of nanopore sensing for in-depth understanding of protein folding landscapes and for drug discovery.Nanopipettes were used for real-time investigation into actin dynamics and drug binding at single-molecule resolution, showing promise for a better understanding of the mechanism of protein–protein interactions and drug discovery. 相似文献
82.
L. V. Grishchuk E. I. Ivanov V. E. Kuz'min A. M. Turyanskaya R. Yu. Ivanova 《Chemistry of Heterocyclic Compounds》2003,39(3):340-343
The reaction of 4-aryl-2-hydrazino-3-nitro-6-R-quinolines with NaNO2 in AcOH gives the corresponding tetrazolo[1,5-a]quinolines. In contrast to tetrazolo[1,5-c]pyrimidines they cannot be converted to 6-R-4-phenyl[1,2,5]oxadiazolo[3,4-b]quinoline-3-oxides by heating in THF, toluene, or AcOH. Total energy quantum-chemical calculations using the MINDO/3 and MNDO methods show that [1,2,5]oxadiazolo[3,4-b]quinoline-3-oxides are significantly higher in energy (230-280 kcal/mol) than the mentioned tetrazolo[1,5-a]quinolines and hence their formation is unlikely. 相似文献
83.
The homotopic method has been used to analyze the kinetic model of three-stageCO oxidation on two nonuniform surface patches conjugated byCO
2 spillover. Diagrams of steady states depending on the portion of surface patchm
1 at various temperatures and pressure ratiosP(O
2)/P(CO) have been constructed. The ratios of different type patches corresponding to the maximum overall reaction rate have been found. 相似文献
84.
V. L. Ivanov V. A. Artemov L. A. Rodinovskaya A. M. Shestopalov V. N. Nesterov Yu. T. Struchkov V. P. Litvinov 《Chemistry of Heterocyclic Compounds》1996,32(1):105-111
Substituted pyrido,[3',2':4,5]thieno[3,2-b]pyndines were obtained by the reaction of 3-amino-2-benzoylthieno [2,3-b]pyridines with malononitrile and the reaction of 3-cyanopyridine-2(IH)-thiones with 2-aryl-3-bromo-I,I-dicyanopropene. 2-Amino-4-(4-bromophenyl)-7, 9-dimethyl-3-cyanopyrido [3',2':4,5]thieno[3, 2-b]-pyridine was used for the synthesis of a derivative of pyrido[3",2":4', 5']thieno[2',3':5,6]pyrido[2,3-d]-pyrimidine. The structure of these compounds was confirmed by spectral data and x-ray diffraction structural analysis.Deceased. 相似文献
85.
The effect of stirring a vanadium-titanium-tellurium catalyst on the yield of the selective oxidation products for oxidation of o-xylene in fluidized bed reactors has been studied. It is shown that the stirring of catalyst pellets increases the yield of phthalic anhydride.
-- - . , .相似文献
86.
Nekrasov A. A. Ivanov V. F. Gribkova O. L. Vannikov A. V. 《Russian Journal of Electrochemistry》2004,40(3):249-258
The electrochemical oxidation–reduction of films of polyaniline is studied in the presence of various counteranions. The differential cyclic voltabsorptometric (DCVA) curves (dA/dt relative to potential, where A is the optical absorption) are recorded at characteristic wavelengths corresponding to individual spectrum components previously isolated with the Alentsev–Fok method. The DCVA curves for aqueous solutions of HCl, HClO4, and H2SO4 at different potential scan rates are compared to traditional cyclic voltammograms. For the DCVA curves obtained at 665 nm discovered is one broad peak of dA/dt in the region of potentials between the first and second stages of polyaniline oxidation (0.6 V vs. Ag/AgCl). An assumption is made about a chemical nature of the process of generation of absorption in this spectral region, which, more likely than not, is connected with the emergence of dimers of radical cations of polyaniline. It is discovered that the electrochemical processes in the region of potentials that correspond to the first stage of oxidation give rise to variations in the absorption inside several regions of spectrum: 435 nm (radical cations) and 755 nm (localized polarons). An assumption is made that the first peak of the current corresponds to several successive processes that occur in a polyaniline molecule in the course of oxidation as well as to the existence of heterogeneous regions where the generation of localized polarons proceeds at different rates. 相似文献
87.
I. N. Ivanov O. K. Nikolaenko A. S. Shtan 《Journal of Radioanalytical and Nuclear Chemistry》1985,90(1):189-196
Expanding application of activation analysis in industry resulted in exposure of features related to higher requirements to productivity, reliability, automation level, metrological support of analytical methods and equipment. Based on the application of neutron generators, radioisotope neutron sources, nuclear reactors, electron accelerators as activating radiation sources, high-productivity activation analytical systems used directly in analytical laboratories and plants were constructed. Level of development of the above works makes it possible to conclude that industrial activation analysis has formed as an independent trend of nuclear analytics and has considerable prospects. 相似文献
88.
S. V. Trepalin A. V. Yarkov V. B. Sokolov A. N. Ivanov 《Russian Chemical Bulletin》1990,39(3):476-480
The potential function has been constructed for internal rotation of the NO-group in (CH3)2CClNO, CH3CCl2NO, and their deuterium analogs. It has been established that the N=O bond in the cisCl conformer of CH3CCl2NO does not eclipse the C-Cl bond, rather forming an angle of approximately 30. It has been shown that a change in substitutent on the -carbon atom may produce a substantial change in the form of the potential function of internal rotation (PFIR) of the NO group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 550–555, March, 1990. 相似文献
89.
90.
B. E. Ivanov S. S. Krokhina T. V. Chichkanova A. B. Ageeva 《Russian Chemical Bulletin》1986,35(12):2535-2539
Conclusion N-Acetoxymethyldiethylamine reacts with tetraethyldiamidophenylphosphonite and diethylamidodiphenylphosphinite, and N-acetoxymethylbenzamide with tetraethyldiamidophenylphosphonite at the phosphorus atom only to form Arbuzov reaction products. The reaction of N-acetoxymethylacetamide with tetraethyldiamidophenylphosphonite and diethylamidodiphenylphosphinite, and the reaction of N-acetoxymethylbenzamide with diethylamidodiphenylphosphinite proceed at two reaction centers at the phosphorus atom to form the Arbuzov reaction products, and at the nitrogen atom to form acetoxyphosphinites (phosphonites) and N-diethylaminomethylamides.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2765–2769, December, 1986. 相似文献