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951.
Wei-Qiang Zhang Nikolay V.Tkachenko Lei Qiao Alexander I.Boldyrev Zhong-Ming Sun 《中国化学》2022,40(1):65-70
Polyarsenides containing coinage metals,[As7Cu(PPh3)]2-(1)and[M2As14]4-(M=Cu,2;Ag,3),were synthesized by reactions of the nominal composition K3As7 with Group 11 metal complexes.The possible intermediate,cluster 1,was isolated from the solution phase through subtle changes in reaction conditions in the formation process of complex 2.Hence,we establish the pathway of the bimetallic bridged clusters[Cu2As14]4-by the oxidation of the[As7Cu(PPh3)]2-.Quantum chemical calculations reveal the presence of metallophilic interaction in clusters 2 and 3. 相似文献
952.
M. G. Voronkov N. M. Kudyakov V. I. Rakhlin A. L. Kuznetsov M. V. Sigalov R. G. Mirskov 《Russian Chemical Bulletin》1985,34(11):2423-2424
Conclusions Phenyl- and diphenylphosphines add to 2,6-dimethyl-2-vinyl-1,3-dioxa-6-aza-2-silacyclooctane upon the action of UV irradiation to form 2,6-dimethyl-2-[(2-phenylphosphino)ethyl)]-1,3-dioxa-6-aza-2-silacyclooctane and 2,6-dimethyl-2-[(2-diphenylphosphino)ethyl]-1,3-dioxa-6-aza-2-silacyclooctane, respectively.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2615–2616, November, 1985. 相似文献
953.
Youhnovski N Matecko I Samalikova M Grandori R 《European journal of mass spectrometry (Chichester, England)》2005,11(5):519-524
Protein charge-state distributions (CSDs) in electrospray-ionization mass spectrometry (ESI-MS) represent a sensitive tool to probe different conformational states. We describe here the effect of trifluoroethanol (TFE) on cytochrome c equilibrium unfolding at different pH by nano-ESI-MS. While even low concentrations of TFE destabilize the protein native structure at low pH, a TFE content of 2.5%-5% is found to favor cyt c folding at pH approximately 7. Furthermore, we perform comparison of CSDs obtained by time-of-flight (ToF) and Fourier-transform-ion- cyclotron-resonance (FT-ICR) mass analyzers. To this purpose, we analyze spectra of cyt c in the presence of different kind of denaturants. In particular, experiments with 1-propanol suggest that also by FT-ICR-MS, as previously observed on an ESI-ToF instrument, CSDs do not appear to be controlled by the solvent surface tension as predicted by the Rayleigh-charge model. Moreover, there is general good agreement in conformational effects revealed by the different instruments under several buffer conditions. Nevertheless, the ToF instrument appears to discriminate better between unfolded and partially unfolded forms. 相似文献
954.
A series of γ,δ-unsaturated azo compounds was prepared by thermal isomerization of allylalkylhydrazones obtained from the simplest carbonyl compounds. The oxidation of N-aminophthalimide with lead tetraacetate in the presence of these unsaturated compounds gave rise to mixtures of adducts at the azo group, regioisomers of phthalimidoazimines. The oxidative addition of N-aminophthalimide to 1-isopropylazocycloalkenes afforded bicyclic C-isopropylazo-N-phthalimidoaziridines, but the same reaction with 2-alkylazopropenes did not result in any adducts with these conjugated azocompounds.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 2, 2005, pp. 214–223.Original Russian Text Copyright © 2005 by Kuznetsov, Belov, Buchaka. 相似文献
955.
Emil D. Krumov Dimitar G. Popov Nikolay S. Starbov 《Central European Journal of Chemistry》2005,3(4):668-673
Thick aluminum oxide films are prepared on Al plates by anodizing. On the ceramic surface thus obtained a very thin Ag film
is deposited via vacuum thermal evaporation. The Ag/Al2O3/Al samples prepared are irradiated by Nd:YAG laser through a suitable metal mask in order to remove the top metal film in
the exposed areas. Thus, a negative silver image of the copied mask is obtained. Further, the samples are processed in Ni
electroless chemical bath activated by the rest of silver. All processing steps are studied by scanning electron microscopy
(SEM). EDS X-ray mapping is applied to study the final distribution of Al and Ni in the processed areas. In addition, the
DC conductivity of the fabricated Ni wires obtained is measured. The proposed new method for selective chemical deposition
of electroconductive Ni onto laser microstructured Ag/Al2O3/Al samples is simple, versatile and not restricted to the metal/ceramic system studied as well as to the electroless deposited
metal. 相似文献
956.
Shram SI Lazurkina TYu Myasoyedov NF Varfolomeyev SD 《Applied biochemistry and biotechnology》1999,82(1):37-56
Synthesis of prostanoids is accompanied by various processes reducing the product yield. These processes are also known to
affect syntheses of thromboxane (TX) and 12(S)-hydroxy-5(Z),8(Z),10(E),14(Z)-eicosatetraenoic acid (12-HETE). Partially purified preparations of TX synthase and prostaglandin
(PG) synthase were used to optimize TX synthesis with respect to concentrations of the enzymes and eicosapolyenoic acid (EPA).
Conditions for the maximum product yield and the minimum consumption of enzymes were determined. Consumption of the TX synthase
was large owing to its inactivation during the reaction and the nonenzymatic destruction of the intermediate product PG-endoperoxide.
Separate addition of PG and TX synthases increased the product yield by preventing EPA sorption on ballast proteins. Microsomal
12-lipoxygenase (12-LO) was also shown to be inactivated during the reaction, and this process was the major limitation of
12-HETE synthesis. Lipoxygenase reaction in the presence of some reducing agents led to a considerable increase of the 12-HETE
yield, supposedly by preventing further oxidation of the 12-LO reaction product 12-hydroperoxy derivative of eicosatetraenoic
acid. The possibility of using human blood platelet microsomes for preparation of some derivatives of EPAs is discussed. 相似文献
957.
Sergey M. Desenko Victoria V. Lipson Oleg V. Shishkin Sergey A. Komykhov Valery D. Orlov Evgeny E. Lakin Valery P. Kuznetsov Herbert Meier 《Journal of heterocyclic chemistry》1999,36(1):205-208
The reaction of 3-amino-1,2,4-triazole ( 1 ) with substituted methyl cinnamates 2a-h leads selectively to the formation of 7-aryl-6,7-dihydro[1,2,4]triazolo[1,5-a]pyrimidin-5(4H)-ones 3a-h . The structure eluci dation of the products is based on ir, 1H and 13C nmr measurements and X-ray diffraction. 相似文献
958.
959.
Kateryna V. Terebilenko Igor V. Zatovsky Nikolay S. Slobodyanik Konstantin V. Domasevitch Denis V. Pushkin Vyacheslav N. Baumer Valentina S. Sudavtsova 《Journal of solid state chemistry》2007,180(12):3351-3359
Phase equilibrium in the pseudo-quaternary system K2O–MoO3–P2O5–Bi2O3 was studied as three-component solvent K2MoO4–KPO3–MoO3 containing 15 mol% Bi2O3 during slow cooling and spontaneous crystallization. The results of the investigation were shown on a composition diagram, which indicates the crystallization fields of K2Bi(PO4)(MoO4), K5Bi(MoO4)4, BiPO4 and K3Bi5(PO4)6. New phosphate K3Bi5(PO4)6 was characterized by single-crystal X-ray diffraction (space group C2/c, a=17.680(4), b=6.9370(14), c=18.700(4) Å, β=113.79(3)°) and FTIR spectroscopy. The possibility of lone electron pair stereoactivity of bismuth was suggested using the calculations of characteristics of the Voronoi–Dirichlet polyhedra for K3Bi5(PO4)6 and K2Bi(PO4)(MoO4). 相似文献
960.
Dr. Dong Heon Nam Dr. Jenny Z. Zhang Virgil Andrei Dr. Nikolay Kornienko Dr. Nina Heidary Andreas Wagner Kenichi Nakanishi Katarzyna P. Sokol Barnaby Slater Dr. Ingo Zebger Prof. Stephan Hofmann Dr. Juan C. Fontecilla‐Camps Prof. Chan Beum Park Prof. Erwin Reisner 《Angewandte Chemie (International ed. in English)》2018,57(33):10595-10599
Hydrogenases (H2ases) are benchmark electrocatalysts for H2 production, both in biology and (photo)catalysis in vitro. We report the tailoring of a p‐type Si photocathode for optimal loading and wiring of H2ase through the introduction of a hierarchical inverse opal (IO) TiO2 interlayer. This proton‐reducing Si|IO‐TiO2|H2ase photocathode is capable of driving overall water splitting in combination with a photoanode. We demonstrate unassisted (bias‐free) water splitting by wiring Si|IO‐TiO2|H2ase to a modified BiVO4 photoanode in a photoelectrochemical (PEC) cell during several hours of irradiation. Connecting the Si|IO‐TiO2|H2ase to a photosystem II (PSII) photoanode provides proof of concept for an engineered Z‐scheme that replaces the non‐complementary, natural light absorber photosystem I with a complementary abiotic silicon photocathode. 相似文献