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11.
A. Zh. Zhakaeva T. Yu. Orlova V. I. Zdanovich V. N. Setkina D. N. Kursanov 《Russian Chemical Bulletin》1977,26(1):202-203
Conclusions The pyridinium cyclopentadienylidechromium(molybdenum) tricarbonyl complexes were synthesized and a study was made of their IR, NMR, and mass spectra.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 227–228, January, 1977.The authors express their gratitude to N. I. Vasyukova and G. A. Panosyan for taking the mass and NMR spectra. 相似文献
12.
Atomic cations (26), M+, have been shown to lie within a thermodynamic window for O-atom transport catalysis of the reduction of N2O by CO and have been checked for catalytic activity at room temperature with kinetic measurements using an inductively-coupled plasma/selected-ion flow tube (ICP/SIFT) tandem mass spectrometer. Only 10 of these 26 atomic cations were seen to be catalytic: Ca+, Fe+, Ge+, Sr+, Ba+, Os+, Ir+, Pt+, Eu+, and Yb+. The remaining 16 cations that lie in the thermodynamic window (Cr+, Mn+, Co+, Ni+, Cu+, Se+, Mo+, Ru+, Rh+, Sn+, Te+, Re+, Pb+, Bi+, Tm+, and Lu+) react too slowly at room temperature either in the formation of MO+ or in its reduction by CO. Many of these reactions are known to be spin forbidden and a few actually may lie outside the thermodynamic window. A new measure of efficiency is introduced for catalytic cycles that allows the discrimination between catalytic cations on the basis of the efficiencies of the two legs of the catalytic cycle. Also, a potential-energy landscape is computed for the reduction of N2O by CO catalyzed by Fe+(6D) that vividly illustrates the operation of an ionic catalyst. 相似文献
13.
Shi T Orlova G Guo J Bohme DK Hopkinson AC Siu KW 《Journal of the American Chemical Society》2004,126(25):7975-7980
Despite reports to the contrary, doubly charged lead monohydrate is a stable species against both proton and charge transfers. [Pb(H(2)O)](2+) has been observed as a minor product in the ligand-exchange reaction of [Pb(CH(3)CN)](2+) with H(2)O after collisional activation. Density functional theory has been used to examine reaction profiles of [Pb(H(2)O)(n)](2+) where n = 1, 2, and 3. 相似文献
14.
M. G. Ezernitskaya B. V. Lokshin T. Yu. Orlova V. N. Setkina V. I. Shilnikov S. Nunziante Cesaro 《Russian Chemical Bulletin》1994,43(11):1841-1845
FTIR spectra have been studied for staircase cyclopentadienyl complexes containing two or three metal carbonyl fragments bound by the metal-carbon bond Cp(CO)2Fe-CpmMn(CO)3 (1), Cp(CO)2Fe-CpmFe(CO)2CH2Ph (2), Cp(CO)2Fe-Cpm(CO)2Fe-CpmMn(CO)3 (3), Cp(CO)2Mo-Cpm(CO)2Fe-CpmMn(CO)3 (4), Cp(CO)3W-Cpm(CO)2Fe-CpmMn(CO)3 (5), Cp(CO)2Fe-Cpm(CO)2Fe-BmCr(CO)3 (6), Cr(CO)3Bm-CpmFe(CO)2CH2Ph (7), where Cp = 5-C5H5, Cpm = 15-C5H4, Bm = 16-C6H5. Temperature-dependent FTIR spectra were measured inn-pentane solutions over a wide temperature range and in the low-temperature solid matrices of argon and nitrogen. Rotamers, formed due to rotation about the metal-carbon -bond, were found in solutions and matrices. A molecular mechanics calculation of1 proved the possibility of such rotation.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1952–1956, November, 1994.The authors are grateful to the Russian Foundation for Basic Research (project code No 93-03-18592) and to the International Science Foundation (project code No MEQ000). 相似文献
15.
F. I. Zubkov V. P. Zaitsev A. A. Orlova A. S. Peregudov N. M. Mikhailova A. V. Varlamov 《Russian Journal of Organic Chemistry》2007,43(8):1202-1208
Dimethyl acetylenedicarboxylate reacts with 4-substituted and 3,4-fused 2-furyl-1,2,3,4-tetrahydroquinoline derivatives at the furan fragment according to the [4 + 2]-cycloaddition pattern. The reaction is not stereoselective, and it yields two diastereoisomeric 7-oxabicyclo[2.2.1]hepta-2,5-dienes whose structure was determined by X-ray analysis and NMR spectroscopy. 相似文献
16.
T. Yu. Orlova Yu. S. Nekrasov P. V. Petrovskii M. G. Ezernitskaya T. V. Magdesieva S. V. Milovanov K. P. Butin 《Russian Chemical Bulletin》1998,47(9):1785-1788
The behavior of binuclear “ladder” type complexes FpL, where Fp=Cp(CO)2Fe, L=p-MeC6H4Cr(CO)3 (4), CH2C6H5Cr(CO)3 (5), andp-FpC6H4Cr(CO)3 (6), under conditions of metallation was studied. Unlike compounds5 and6, the σ-bound ligand L in compound4 migrates from the iron atom to the cyclopentadienyl ring to give complexes Me(CO)2FeC5H4−C6H4(p-Me)Cr(CO)3. The electrochemical reduction potentials of the complexes4–6 and the rearrangement products were measured. The migration activity of L is determined by the ease of reductive cleavage
of the Fe−L bond and the susceptibility of the system to undergo intramolecular electron transfer from the Cp ligand to the
aromatic ring.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1832–1835, September, 1998. 相似文献
17.
V. P. Tashchi T. I. Rukasov Yu. G. Orlova Yu. A. Putsykin Yu. A. Baskakov 《Chemistry of Heterocyclic Compounds》1982,18(6):566-568
2-(-Oximinoethyl)-2-methylthiirane was obtained by the reaction of 3,4-dibromo-3-methyl-2-butanone oxime with sodium sulfide. At the same time, the O-carbamoyl derivative of the ,-dibromo oxime was converted to the corresponding substituted ,-unsaturated oxime under the same conditions. Thiirane oxime, like its O-carbamoyl derivative, underwent the desulfuration that is characteristic for thirranes under the influence of tributylphosphine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 751–753, June, 1982. 相似文献
18.
Dudkin VY Orlova M Geng X Mandal M Olson WC Danishefsky SJ 《Journal of the American Chemical Society》2004,126(31):9560-9562
Synthetic gp120331-335 glycopeptide fragments carrying hybrid and high-mannose type N-linked glycans were evaluated for binding to broadly neutralizing antibody 2G12 using surface plasmon resonance technology. None of the hybrid-type constructs demonstrated binding to 2G12. In the high-mannose series, the "Cys dimer" construct, presenting two undecasaccharide glycans, showed significantly higher binding than the Cys-protected monomer. The binding of the dimeric structure was further investigated in competition with recombinant gp120. The data suggest that gp120 and its designed synthetic epitope construct bind to the same site on 2G12. 相似文献
19.
Adamovich MI Aggarwal MM Alexandrov YA Andreeva NP Anson ZV Arora R Avetyan FA Badyal SK Basova E Bazarov IK Bhalla KB Bhasin A Bhatia VS Bogdanov VG Bubnov VI Burnett TH Cai X Carshiev DA Chasnicov IY Chernova LP Chernyavski MM Eligbaeva GZ Eremenko LE Gaitinov AS Ganssauge ER Garpman S Gerassimov SG Grote JG Gulamov KG Gupta SK Gupta VK Heckman HH Huang H Jacobsson B Judek B Kachroo S Kalyachkina GS Kanygina EK Karabova M Kharlamov SP Kitroo S Koss T Krasnov SA Kumar V Lal P Larionova VG 《Physical review D: Particles and fields》1993,47(9):3726-3732
20.
M. A. Yurovskaya A. Z. Afanas'ev I. A. Orlova V. A. Chertkov 《Chemistry of Heterocyclic Compounds》1993,29(11):1281-1286
Alkyl-3-nitropyridinium salts react with DMF diethylacetal to give -aminovinyl derivatives under considerably milder conditions than with the corresponding bases. The regioselectivity of this process has been studied in dependence on the structure and positions of the alkyl substituents in the initial salt.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1488–1494, November, 1993.This work was carried out with a grant from the Russian Fund for Fundamental Research (project # 93-03-4593). 相似文献