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21.
Kazbanov V. I. Starkov A. K. Kozhukhovskaya G. A. Kazbanova T. K. Trofimov V. I. Pavlenko N. I. 《Russian Journal of Coordination Chemistry》2001,27(1):65-69
A comparison study of the bis(-oxalato)tetramminediplatinum(II) dimer [Pt2(NH3)4(-C2O4)2] and the oxalatodiammineplatinum(II) chelate [Pt(NH3)2C2O4] is performed. The kinetics and mechanism of substitution of C2O2–
4 for Cl– in aqueous chloride solutions are studied by photoelectronic spectroscopy, gravimetry, and chemical phase analysis within the 1.0–6.7 pH range at 75°C. The rate constants of substitution and the equilibrium constants for a two-step protonation for the dimeric and chelate complexes are calculated. Their solubility in 1 M KCl at 75°C; is determined. The unit cell parameters for [Pt2(NH3)4(-C2O4)2] are determined: a = 3.858 Å, b = 10.704 Å, c = 6.795 Å, = 94.35°. The IR spectra of [Pt(NH3)2C2O4], [Pt2(NH3)4(-C2O4)2], and their deuterated analogs are studied. 相似文献
22.
V. A. Shagun O. A. Tarasova B. A. Trofimov 《Russian Journal of Organic Chemistry》2006,42(7):1039-1044
Reactions of pyrrole, imidazole, pyrazole, and 1,2,4-triazole with allene and propyne in the gas phase with formation of the corresponding N-isopropenylazoles were simulated at the RHF/6-31G**, B3LYP/6-31G**, and MP2(full)/6-31G** levels. Dissociation of the N-H bond to give azolate ion is the main constituent of the reaction coordinate. All the examined azoles react preferentially with allene rather than with propyne; their reactivity decreases in the series pyrrole > imidazole > pyrazole > 1,2,4-triazole due to participation of the pyridine type nitrogen atoms in the prototropic propyne-allene rearrangement. 相似文献
23.
The electron-transfer-catalyzed rearrangement of the housanes 1 affords regioselectively the two cyclopentenes 2 and 3 by 1,2-migration of a group at the methano bridge. Appropriate ring annelation in the intermediary cyclopentane-1,3-diyl radical cation 1(*+) changes the stereochemical course of the rearrangement from complete stereoselectivity (stereochemical memory) for the structurally simple housane 1b to partial loss of stereoselectivity through competing conformational interconversion for the tricyclic housane 1c. Additional cyclohexane annelation, as in the tetracyclic housane 1a, results in complete loss of stereocontrol through Curtin-Hammett behavior, as substantiated by the viscosity dependence on the product ratio of the rearrangement. Whereas in the radical cations 1b(*+) and 1c(*+) the 1,2-shifts (k(2) and k(3)) are faster than the conformational anti <==> syn change (k(1), k(-1)), the reverse applies for the radical cation 1a(*+). Such structural manipulation of conformational effects in radical cation rearrangements has hitherto not been documented. 相似文献
24.
The method for dynamic crystallization of II—VI compounds with a gaseous control of vapour concentrations in the growth zone is developed. The predeterminated change of the transport gas flows which carry the vapours of the initial elements into the reaction zone together with the change of additional inert gas flows conducted directly to the crystallizer entries gives the posibility to displace the growth zone during the process of synthesis. It results in the considerable increase in crystal number and size and leads to best quality of grown crystals. 相似文献
25.
26.
Boris Trofimov Nina Gusarova Lambert Brandsma 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):601-604
Abstract Generation of phosphide anions from phosphorus red or phosphine under the action of strong bases followed by their reactions with organyl halides, electrophilic alkenes and alkynes proves to be the most straightforward and well-controlled route to mono-, di- or triorganylphosphines or phosphine oxides of diverse structure. 相似文献
27.
28.
Kulyako Yu. M. Trofimov T. I. Pilyushenko K. S. Vinokurov S. E. Myasoedov B. F. 《Physics of Atomic Nuclei》2020,83(10):1396-1399
Physics of Atomic Nuclei - The use of microwave heating to produce solid solutions of actinide oxides in the processes of thermal denitration of model nitric acid solutions formed in reducing... 相似文献
29.
The feasibility of an optical switch of femtosecond range controlled by a femtosecond light pulse acting on a nonlinear one-dimensional photonic crystal (a layered one-dimensional periodic structure) is demonstrated by computer simulation. The crystal comprises linear and weakly defocusing layers. It is shown that switching occurs when the peak intensity of the initial pulse exceeds a certain threshold value due to the dependence of the transmission-reflection bands of the photonic crystal on the nonlinearity of the medium. 相似文献
30.
B. A. Trofimov T. A. Skotheim L. V. Andriyankova A. G. Malkina G. F. Myachina S. A. Korzhova T. I. Vakul'skaya I. P. Kovalev Yu. V. Mikhailik 《Russian Chemical Bulletin》1999,48(3):459-462
Polydiethylsiloxane reacts with elemental sulfur at 300–320 °C (ZnCl2 slightly accelerates the process) with evolution of hydrogen sulfide and formation of black lustrous paramagnetic powders (sulfur content up to 38.50%), which possess a noticeable electric conductivity (3.20·10−7 S cm−1 when doped with I2) and redox properties. Polydimethylsiloxanes are stable under the same conditions. In rechargeable lithium batteries, the sulfurized polydiethylsiloxane behaves as an active cathode material allowing charging and discharging of the battery. The specific capacities of the cathodic and anodic processes (80–100 (mA h) g−1) change insignificantly. The hydrolytic stability, elemental analysis, IR and ESR spectra, DSC-TGA and derivatographic analyses data, the electric conductivity, and the character of the electrochemical activity of the polymers synthesized indicate that the polymers contain the polyvinylene disulfide blocks cross-linked by the polysiloxane chain. 相似文献