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61.
N. N. Golovnev A. A. Leshok G. V. Novikova 《Russian Journal of Inorganic Chemistry》2010,55(2):291-293
The effect of acidity and equilibrium chloride ion concentration on the interaction of PdCl4 2- with cystine (H2CySS) in hydrochloric acid solutions was studied. Pd(H4CySS)Cl3+ complex was found to form at [Cl–] = 1.0, 0.5, or 0.25 mol/Linthe [H+] range from 0.10 to 1.00 mol/L; the relevant equilibrium constant was determined. Monodentate coordination of cystine to palladium(II) through the sulfur atom was proposed on the basis of analysis of conditional stability constants as functions of [Cl–] and [H+]. 相似文献
62.
Rose Mary Michell Alejandro J. Müller Mariya Spasova Philippe Dubois Stefano Burattini Barnaby W. Greenland Ian W. Hamley Daniel Hermida‐Merino Nicolas Cheval Amir Fahmi 《Journal of Polymer Science.Polymer Physics》2011,49(19):1397-1409
The thermal properties, crystallization, and morphology of amphiphilic poly(D ‐lactide)‐b‐poly(N,N‐dimethylamino‐2‐ethyl methacrylate) (PDLA‐b‐PDMAEMA) and poly (L ‐lactide)‐b‐poly(N,N‐dimethylamino‐2‐ethyl methacrylate) (PLLA‐b‐PDMAEMA) copolymers were studied and compared to those of the corresponding poly(lactide) homopolymers. Additionally, stereocomplexation of these copolymers was studied. The crystallization kinetics of the PLA blocks was retarded by the presence of the PDMAEMA block. The studied copolymers were found to be miscible in the melt and the glassy state. The Avrami theory was able to predict the entire crystallization range of the PLA isothermal overall crystallization. The melting points of PLDA/PLLA and PLA/PLA‐b‐PDMAEMA stereocomplexes were higher than those formed by copolymer mixtures. This indicates that the PDMAEMA block is influencing the stability of the stereocomplex structures. For the low molecular weight samples, the stereocomplexes particles exhibited a conventional disk‐shape structure and, for high molecular weight samples, the particles displayed unusual star‐like shape morphology. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1397–1409, 2011 相似文献
63.
L. N. Novikova B. A. Mazurchik N. A. Ustynyuk S. V. Kukharenko V. V. Strelets 《Russian Chemical Bulletin》1994,43(2):299-303
New cationic complexes [(6-C13H10)Fe(5-Cp*)]PF6 and [(6-9-CH3-C13H9)Fe(5-Cp*)]PF6 were obtained by the reaction of Cp*Fe(CO)2Br with fluorene and 9-methylfluorene, respectively. Deprotonation of these complexes byt-BuOK in THF affords zwitter-ionic compounds (6-C13H9)Fe(5-Cp*) and (6-9-CH3-C13H8)Fe(5-Cp*) (A). WhenA is heated in nonane at 150 °C it undergoes 65 inter-ring rearrangement with the formation of hexamethyldibenzoferrocene (B). The electrochemical behavior ofA andB was studied by cyclic voltammetry. One-electron reduction ofA andB to the corresponding radical anions induces inter-ring haptotropic rearrangementA
.–B
.–. The equilibrium in the 19 state is shifted to the 6-isomeric radical anionA
.–, while in the 18 precursors, it shifts to the 5-isomerB.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 319–324, February, 1994.The authors are grateful to D. V. Zagorevskii (A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences) for recording and interpreting the mass spectra, and to A. A. Borisenko (Moscow State University) for recording the NMR spectra.This work was financially supported by the Russian Foundation for Basic Research (Grant 93-03-5209). 相似文献
64.
The reaction of O-methyl tetramethyldiamidophosphite with 3-bromopropanol or 3-bromo-2-butanol occurs with the liberation of dimethylamine and results in mixed phosphites. The reaction of O-methyl tetramethyldiamidophosphite with 3-thiocyano-2-butanol proceeds with the participation of the sulfur atom of the thiocyano group and formation ofS-(3-hydroxybutyl) tetramethyldiamidothiophosphate.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 167–169, January, 1994. 相似文献
65.
66.
Stanislav N. Naryzhny Victor G. Zgoda Maria A. Maynskova Svetlana E. Novikova Natalia L. Ronzhina Igor V. Vakhrushev Elena V. Khryapova Andrey V. Lisitsa Olga V. Tikhonova Elena A. Ponomarenko Alexander I. Archakov 《Electrophoresis》2016,37(2):302-309
Virtual and experimental 2DE coupled with ESI LC‐MS/MS was introduced to obtain better representation of the information about human proteome. The proteins from HEPG2 cells and human blood plasma were run by 2DE. After staining and protein spot identification by MALDI‐TOF MS, the protein maps were generated. The experimental physicochemical parameters (pI/Mw) of the proteoforms further detected by ESI LC‐MS/MS in these spots were obtained. Next, the theoretical pI and Mw of identified proteins were calculated using program Compute pI/Mw ( http://web.expasy.org/compute_pi/pi_tool‐doc.html ). Accordingly, the relationship between theoretical and experimental parameters was analyzed, and the correlation plots were built. Additionally, virtual/experimental information about different protein species/proteoforms from the same genes was extracted. As it was revealed from the plots, the major proteoforms detected in HepG2 cell line have pI/Mw parameters similar to theoretical values. In opposite, the minor protein species have mainly very different from theoretical pI and Mw parameters. A similar situation was observed in plasma in much higher degree. It means that minor protein species are heavily modified in cell and even more in plasma proteome. 相似文献
67.
V. N. Voshula Yu. B. Vysotskii V. I. Seraya N. T. Novikova R. Ya. Mushii V. I. Dulenko 《Chemistry of Heterocyclic Compounds》1990,26(12):1349-1357
The interaction of 1-methallylpyrazoles with acetic or propionic anhydride in the presence of perchloric acid forms products of acylation at the double bond and subsequent heterocyclization — pyrazolo[1,2-a]pyridazinium salts — that are representatives of a new heteroaromatic system. Analogous cyclization is observed in the acylation of 3-(2-hydroxy-2-methylpropyl-pyrazole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1623–1631, December, 1990. 相似文献
68.
L. M. Likhosherstov O. S. Novikova L. O. Kononov A. V. Orlova I. B. Sivaev V. I. Bregadze 《Russian Chemical Bulletin》2007,56(10):2105-2108
Conjugates of β-lactosylamine derivatives bearing terminal amino groups in aglycon with ortho-carboranylacetic acid were synthesized. Five glycoconjugates with spacers of different length (from 9 to 18 atoms) and hydrophilicity
containing di-, tri-, and pentapeptide fragments constructed of glycine and serine residues and spacers incorporating ethylenediamine
and tartaric acid or tertiary amine residues were prepared
Dedicated to the memory of outstanding chemist and biochemist V. N. Shibaev.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2033–2036, October, 2007. 相似文献
69.
Nikolai A. Ustynyuk Oleg V. Gusev Lyudmila N. Novikova Mikhail G. Peterleitner Larisa I. Denisovich Tat’yana A. Peganova Oleg V. Semeikin Dmitry A. Valyaev 《Journal of Solid State Electrochemistry》2007,11(12):1621-1634
In this review, redox-induced reactions of π- and σ,π-complexes leading to the selective formation (or cleavage) of C–H, C–C,
and C–O bonds have been summarized. To illustrate the synthetic potential of such methodology, the following representative
reactions studied in our group are discussed: (1) oxidatively induced hydrogen elimination from “open” cyclic diene and dienyl
complexes resulting in formation of “closed” dienyl and arene complexes, respectively; (2) reductive activation of C–H bonds
in diene, vinylidene, and carbyne complexes forming new multiple C–C bonds; (3) oxidative dehydrodimerization of vinylidene
complexes into binuclear μ-divinylidene species; and (4) oxidatively induced addition of oxygen nucleophiles to μ-divinylidene
complexes affording cyclic μ-dicarbene derivatives.
Oleg V. Gusev, deceased on October 31. 相似文献
70.
An oxidosqualene cyclase makes numerous products by diverse mechanisms: a challenge to prevailing concepts of triterpene biosynthesis 总被引:1,自引:0,他引:1
Lodeiro S Xiong Q Wilson WK Kolesnikova MD Onak CS Matsuda SP 《Journal of the American Chemical Society》2007,129(36):11213-11222
The genome of the model plant Arabidopsis thaliana encodes 13 oxidosqualene cyclases, 9 of which have been characterized by heterologous expression in yeast. Here we describe another cyclase, baruol synthase (BARS1), which makes baruol (90%) and 22 minor products (0.02-3% each). This represents as many triterpenes as have been reported for all other Arabidopsis cyclases combined. By accessing an extraordinary repertoire of mechanistic pathways, BARS1 makes numerous skeletal types and deprotonates the carbocation intermediates at 14 different sites around rings A, B, C, D, and E. This undercurrent of structural and mechanistic diversity in a superficially accurate enzyme is incompatible with prevailing concepts of triterpene biosynthesis, which posit tight control over the mechanistic pathway through cation-pi interactions, with a single proton acceptor in a hydrophobic active site. Our findings suggest that mechanistic diversity is the default for triterpene biosynthesis and that product accuracy results from exclusion of alternative pathways. 相似文献