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111.
V. Karimäki R. Kinnunen M. Korkea-aho J. Tuominiemi G. W. van Apeldoorn D. Harting D. J. Holthuizen B. J. Pijlgroms P. Johnson P. Mason P. Michaelides Ch. Michaelidou H. Muirhead G. D. Patel G. Ekspong T. Moa S. Nilsson 《Zeitschrift fur Physik C Particles and Fields》1981,9(2):117-129
Inclusive production of ?0,K *±(892), andf is studied in \(\bar p\) p interactions at 12 GeV/c. The inclusive cross sections for ?0,K *±(892), andf are found to be 6.7±0.3 mb, 1.0±0.2 mb, and 1.4±0.3 mb, respectively. The differential cross sections are presented as a function of c.m. rapidity, Feynmanx and square of the transverse momentump T 2 . Comparison with the correspondingpp data shows some interesting differences which can be attributed to the \(\bar p\) p annihilation. The results are compared with the predictions of the quark fusion model. 相似文献
112.
Ivan panik Jan Krupcik Ivan Skacani Jaap De Zeeuw Mario Galli Pat Sandra 《Journal of separation science》1997,20(12):688-692
The separation of isomers and enantiomers of branched C10-C12 phenylalkanes by gas chromatography on fused silica capillary columns coated with some modified β- and γ-cyclodextrins was studied. It was shown that the separation of positional isomers of C10-C12 phynylalkanes on modified cyclodextrin capillary columns is not better than that on a column coated with modified polyethylene glycol. Differences were found in the enantioselectivity of modified β- and γ-cyclodextrins for the separation of C10-C12 secondary phenylalkane enantiomers. While alkylderivatives of β-CDs resolve enantiomers of 3-phenylalkanes, alkyl derivatives of γ-CD resolve enantiomers of 2-phenylalkanes. Since shape selectivity factors of modified cyclodextrins have indicated no inclusion of the considered solutes in cyclodextrin cavities, enantioselective interactions most probably occur on the outer sphere of cyclodextrins. 相似文献
113.
114.
Alexey Sulimov Ivan Ilin Danil Kutov Khidmet Shikhaliev Dmitriy Shcherbakov Oleg Pyankov Nadezhda Stolpovskaya Svetlana Medvedeva Vladimir Sulimov 《Molecules (Basel, Switzerland)》2022,27(17)
Candidates to being inhibitors of the main protease (M) of SARS-CoV-2 were selected from the database of Voronezh State University using molecular modeling. The database contained approximately 19,000 compounds represented by more than 41,000 ligand conformers. These ligands were docked into M using the SOL docking program. For one thousand ligands with best values of the SOL score, the protein–ligand binding enthalpy was calculated by the PM7 quantum-chemical method with the COSMO solvent model. Using the SOL score and the calculated protein–ligand binding enthalpies, eighteen compounds were selected for the experiments. Several of these inhibitors suppressed the replication of the coronavirus in cell culture, and we used the best three among them in the search for chemical analogs. Selection among analogs using the same procedure followed by experiments led to identification of seven inhibitors of the SARS-CoV-2 replication in cell culture with EC values at the micromolar level. The identified inhibitors belong to three chemical classes. The three inhibitors, 4,4-dimethyldithioquinoline derivatives, inhibit SARS-CoV-2 replication in Vero E6 cell culture just as effectively as the best published non-covalent inhibitors, and show low cytotoxicity. These results open up a possibility to develop antiviral drugs against the SARS-CoV-2 coronavirus. 相似文献
115.
Grigorii Alexandrovich Mironenko Ivan Alexandrovich Zagorskii Nataliya Anatolievna Bystrova Konstantin Alexandrovich Kochetkov 《Molecules (Basel, Switzerland)》2022,27(19)
The research object was the liquid protein hydrolysate “AGROMOREE” from the rainbow trout, which was provided by the company “Russian Aquaculture LLC”. The purpose of this study was the evaluation of the effect of the hydrolysate “AGROMOREE” as a biostimulant on the growth and yield of wheat (Triticum aestivum L.). Biometric indicators of wheat (Triticum aestivum L.) growth were determined in the laboratory and in field tests. In the laboratory, the liquid concentrated hydrolysate was dried to facilitate its use. “AGROMOREE” promoted an increase in germination of 2–4% in all samples compared to the control samples, as well as an increase in the length and number of wheat roots. The biostimulant “AGROMOREE” was introduced in the soil in liquid form at about 3000 L/ha and 4000 L/ha in the field tests. This study showed that “ARGOMOREE” contributed to an increase in the length and quantity of wheat ears, the quantity of grains in the ear and the seed weight. At the same time, the quantity of productive stems increased, so that the biostimulant “AGROMOREE” increased the productivity by 3.9–6.3% with respect to the control sample. In general, using the biostimulant “AGROMOREE” on spring wheat seeds from 2019 in the growing season of 2021 provided an increase in yield from 0.21 t/ha to 0.28 t/ha. The maximum value of raw gluten content in the seed was 5.2%, higher than the content in the control. The content of the mass fraction of protein in the seed was in the range of 12.33–12.56%, i.e., 2% higher than that of the control sample. Thus, according to qualitative and quantitative indicators and the total productivity indicators, the biostimulant «AGROMOREE» can be used to increase wheat productivity and reduce the use of nitrogen fertilizers. 相似文献
116.
Anton S. Ganin Mikhail Yu. Moskalik Ivan A. Garagan Vera V. Astakhova Bagrat A. Shainyan 《Molecules (Basel, Switzerland)》2022,27(20)
Allyl halides with triflamide under oxidative conditions form halogen-substituted amidines. Allyl cyanide reacts with triflamide in acetonitrile or THF solutions in the presence of NBS to give the products of bromotriflamidation with a solvent interception, whereas in CH2Cl2 two regioisomers of the bromotriflamidation product without a solvent interception were obtained. The formed products undergo base-induced dehydrobromination to give linear isomers with the new C=C bond conjugated either with the nitrile group or the amidine moiety or alkoxy group. Under the same conditions, the reaction of allyl alcohol with triflamide gives rise to amidine, which was prepared earlier by the reaction of diallyl formal with triflamide. Unlike their iodo-substituted analogs, bromo-substituted amidines successfully transform into imidazolidines under the action of potassium carbonate. 相似文献
117.
Eugene P. Kramarova Sophia S. Borisevich Edward M. Khamitov Alexander A. Korlyukov Pavel V. Dorovatovskii Anastasia D. Shagina Konstantin S. Mineev Dmitri V. Tarasenko Roman A. Novikov Alexey A. Lagunin Ivan Boldyrev Aiarpi A. Ezdoglian Natalia Yu. Karpechenko Tatiana A. Shmigol Yuri I. Baukov Vadim V. Negrebetsky 《Molecules (Basel, Switzerland)》2022,27(21)
The synthesis of the products of the 1,3-propanesultone ring opening during its interaction with amides of pyridinecarboxylic acids has been carried out. The dependence of the yield of the reaction products on the position (ortho-, meta-, para-) of the substituent in the heteroaromatic fragment and temperature condition was revealed. In contrast to the meta- and para-substituted substrates, the reaction involving ortho-derivatives at the boiling point of methanol unexpectedly led to the formation of a salt. On the basis of spectroscopic, X-Ray, and quantum-chemical calculation data, a model of the transition-state, as well as a mechanism for this alkylation reaction of pyridine carboxamides with sultone were proposed in order to explain the higher yields obtained with the nicotinamide and its N-methyl analog compared to ortho or meta parents. Based on the analysis of ESP maps, the positions of the binding sites of reagents with a potential complexing agent in space were determined. The in silico evaluation of possible biological activity showed that the synthetized compounds revealed some promising pharmacological effects and low acute toxicity. 相似文献
118.
Daria V. Vorobyeva Dmitry A. Petropavlovskikh Ivan A. Godovikov Fedor M. Dolgushin Sergey N. Osipov 《Molecules (Basel, Switzerland)》2022,27(23)
A convenient pathway to a new series of α-CF3-substituted α-amino acid derivatives bearing pharmacophore isoquinolone core in their backbone has been developed. The method is based on [4+2]-annulation of N-(pivaloyloxy) aryl amides with orthogonally protected internal acetylene-containing α-amino carboxylates under Rh(III)-catalysis. The target annulation products can be easily transformed into valuable isoquinoline derivatives via a successive aromatization/cross-coupling operation. 相似文献
119.
Dmitriy S. Yambulatov Irina A. Lutsenko Stanislav A. Nikolaevskii Pavel A. Petrov Ivan V. Smolyaninov Irina K. Malyants Victoria O. Shender Mikhail A. Kiskin Alexey A. Sidorov Nadezhda T. Berberova Igor L. Eremenko 《Molecules (Basel, Switzerland)》2022,27(23)
Three new Pt(II) complexes [(dpp-DAD)PtCl2] (I), [(Mes-DAD(Me)2)PtCl2] (II) and [(dpp-DAD(Me)2)PtCl2] (III) were synthesized by the direct reaction of [(CH3CN)2PtCl2] and corresponding redox-active 1,4-diaza-1,3-butadienes (DAD). The compounds were isolated in a single crystal form and their molecular structures were determined by X-ray diffraction. The purity of the complexes and their stability in solution was confirmed by NMR analysis. The Pt(II) ions in all compounds are in a square planar environment. The electrochemical reduction of complexes I–III proceeds in two successive cathodic stages. The first quasi-reversible reduction leads to the relatively stable monoanionic complexes; the second cathodic stage is irreversible. The coordination of 1,4-diaza-1,3-butadienes ligands with PtCl2 increases the reduction potential and the electron acceptor ability of the DAD ligands. The synthesized compounds were tested in relation to an adenocarcinoma of the ovary (SKOV3). 相似文献
120.
Alena L. Stalinskaya Nadezhda V. Martynenko Zarina T. Shulgau Alexandr V. Shustov Viktoriya V. Keyer Ivan V. Kulakov 《Molecules (Basel, Switzerland)》2022,27(12)
The COVID-19 pandemic is ongoing as of mid-2022 and requires the development of new therapeutic drugs, because the existing clinically approved drugs are limited. In this work, seven derivatives of epoxybenzooxocinopyridine were synthesized and tested for the ability to inhibit the replication of the SARS-CoV-2 virus in cell cultures. Among the described compounds, six were not able to suppress the SARS-CoV-2 virus’ replication. One compound, which is a derivative of epoxybenzooxocinopyridine with an attached side group of 3,4-dihydroquinoxalin-2-one, demonstrated antiviral activity comparable to that of one pharmaceutical drug. The described compound is a prospective lead substance, because the half-maximal effective concentration is 2.23 μg/μL, which is within a pharmacologically achievable range. 相似文献