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991.
L. I. Kas’yan S. I. Okovityi I. N. Tarabara A. O. Kas’yan Ya. S. Bondarenko 《Russian Journal of Organic Chemistry》2005,41(6):816-824
4-Azatricyclo[5.2.1.02,6]dec-8-ene was synthesized and brought into reactions with benzoyl, o-chlorobenzoyl, p-bromobenzoyl, p-, m-, and o-nitrobenzoyl, and bicyclo[2.2.1]hept-2-ene-endo-5,endo-6-dicarboximidoacetyl chlorides in chloroform in the presence of pyridine. The tricyclic amides thus obtained were epoxidated with peroxyphthalic acid prepared in situ by reaction of phthalic anhydride with a 35% aqueous solution of hydrogen peroxide. The structure of newly synthesized compounds was confirmed by IR and 1H and 13C NMR spectroscopy and mass spectrometry. Their NMR spectra were compared with those of previously synthesized N-arylsulfonyl-4-azatricyclo[5.2.1.02,6]dec-8-enes on the basis of conformational composition of the corresponding p-nitrophenyl-substituted derivatives, which was determined by PM3 semi-empirical quantum-chemical calculations.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 6, 2005, pp. 837–845.Original Russian Text Copyright © 2005 by L. Kas’yan, Okovityi, Tarabara, A. Kas’yan, Bondarenko. 相似文献
992.
E. L. Gaidarova K. Rosher A. É. Aliev G. V. Grishina 《Chemistry of Heterocyclic Compounds》1992,28(10):1175-1178
Enantiomericalfy pure (–)-(10S)-6,10-dimethyl-6-am-1,9-octahydroquinoline, which has been obtained from optically pure (3S)-1,3-dimethyl-3-(2-cyanoethyl)piperid-4-one, is a chiral intermediate for the preparation of novel biologically active compounds and an analog of piperidine and decahydroquinoline alkaloids. The chiroptical properties of the synthesized 6-azaoctahydroquinoline are examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1379–1383, October, 1992. 相似文献
993.
K. L. Lutfullin M. M. Tadzhibaev V. M. Malikov U. A. Abdullaev U. Rakhmankulov 《Chemistry of Natural Compounds》1977,12(6):696-699
Summary The biosynthesis of the alkaloids ofAmmothamnus lehmannii Bge. have been studied by supplying the plants with [1,5-14C2] cadaverine. It has been shown that cadaverine is a precursor of sophocarpidine, sophocarpine, and pachycarpine. Possible routes of interconversions have been studied by supplying the plants with the tritium-labelled alkaloids [3H] sophocarpine, [3H] matrine, and [3H] pachycarpine.V. I. Lenin Tashkent State University. Institute of Plant Biochemistry, Academy of Sciences of the German Democratic Republic, Halle. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 776–780, November–December, 1976. 相似文献
994.
The exchange reaction of D2 with OH groups of HY zeolites was followed both in the solid and gas phase by IR and MS. The rates of D2–OH and D2–H2 exchange increase considerably with dehydroxylation of the sample. The active centers are probably vacancies formed by removal of oxygen from the lattice, they catalyze the dissociation of D2. Dehydroxylation of the sample is accompanied by the formation of 3 740 cm–1 hydroxyls, whose exchange with D2 is slower than that with other OH groups and which affect the kinetics in the gas phase.
D2 OH HY - O2–OH O2–H2 . , , , O2. OH, 3740 –1, , OH .相似文献
995.
L. S. Ettre 《Chromatographia》1994,38(7-8):521-526
Summary The most important definitions, terms and symbols included in the new, unified Nomenclature for Chromatography issued by the International Union of Pure and Applied Chemistry (IUPAC) are outlined. 相似文献
996.
J. Margitfalvi S. Gbölös E. Kwaysser M. Hegedüs F. Nagy L. Koltai 《Reaction Kinetics and Catalysis Letters》1984,24(3-4):315-321
The influence of rhenium on the behavior of a Pt/Al2O3 catalyst was studied in n-hexane reaction by means of dilution of the catalyst bed with Re/Al2O3. Parallel to activity, selectivity and ageing data obtained in slug pulse and continuous flow reactors, the amount of the surface carbon formed during the reaction was determined and its reactivity in hydrogen atmosphere was also studied. It is suggested that in the presence of rhenium due to the increase in the amount of hydrogen available for hydrogen consuming reactions including hydrodepolymerization of the carbonaceous surface overlayer, the routes of ageing processes are changed, resulting in lower carbon content on the catalyst and less pronounced catalyst deactivation.
Pt/Al2O3 -, Re/Al2O3. , , , , . , , , , , , , .相似文献
997.
The mass spectra of eight nitrosamines have been recorded, with excitation by chemical ionization (CI) and electron impact (EI). Comparison of the intensities of the base peaks under CI and El conditions gives intensity ratios in the range 1.4-1.9 for low resolution measurements and up to 10 for high resolution measurements, confirming the enhanced sensitivity available in the CI mode. 相似文献
998.
J. T. Guthrie L. J. Squires 《Journal of polymer science. Part A, Polymer chemistry》1984,22(1):135-144
The effect of a range of 10 organic nitriles on the radiation-induced polymerization of styrene was studied. A dose rate of 4.4 rad s?1 was used. A rate of polymerization of styrene (1.744 mol L?1 of toluene solution) of 5.0 × 10?7 mol L?1 s?1 was found. With organic nitriles present (styrene:nitrile ratio of 1:0.28) the rate of polymerization increased. Rates in the range of 5.5 × 10?7 ?5.2 × 10?6 mol L?1 s?1, depending on the nitrile present, were obtained. The polymers were partially characterized and evidence of involvement of each of the nitriles in the polymer chains was revealed. The increase in rate of polymerization has been attributed to the part played by nitrile radicals in the initiation of styrene polymerization. Radical yield values [as G(nitrile radical)] were derived from the relevant rate expressions. Values ranged from 2.7 to 49.5, depending on the particular nitrile. Corresponding values of G(nitrile radical) in the range of 5.1–129.4 were obtained by the manipulation of number-average molar mass data. Values of kpkt of approximately 2 × 10?5 L mol?1 s?1 were found. Trommsdorff types of effect are absent from these systems. 相似文献
999.
The thermal degradation of a highly chlorinated paraffin, (Cl 70% w/w)(CP), used as a fire retardant additive for polymers, has been studied by TG, DTA and TVA. The main volatile degradation product is HCl which is eliminated in two steps. To 60–70% dehydrochlorination an apparent zero order reaction occurs with a detectable rate from 250°C, probably initiated at labile chlorine atoms. The apparent activation energy of the process is 40 kcal/mole. A charred residue containing 35% chlorine is obtained. This residue undergoes nearly complete dehydrochlorination in the range 300–600°C. 相似文献
1000.
W. Lautsch W. Broser W. Bandel W. Biedermann W. Gehrmann E. Schröder H. Gnichtel I. Zehmisch G. Kurth R. Krüger H. J. Kraege 《Colloid and polymer science》1954,138(3):129-142
Ohne Zusammenfassung
Die Arbeit wurde aus Mitteln des Marshall-Planes (ERP-Mittel) und mit Spenden aus dem „Fonds Chemie“ ausgeführt. Wir sprechen
den zust?ndigen Stellen für die Gew?hrung der Beihilfe unseren verbindlichsten Dank aus. Der Deutschen Forschungsgemeinschaft
danken wir für die überlassung einer Ultrazentrifuge, den Behring-Werken für die uns zur Verfügung gestellten Serumalbumin-
und -globulin-Pr?parate. 相似文献