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51.
The synthetic samples of nickel olivine were measured in the temperature range 100–630 K by the X-ray powder diffraction method. Temperature dependencies of molar volumes and coefficients of bulk thermal expansion of liebenbergite were determined. Interpolation and extrapolation of the experimental data were performed by the procedure based on the Debye–Mie–Gruneisen theory of solid body in the range from 50 to 2000 K, and the Gruneisen coefficient and Debye temperature were calculated. Heat capacity and its behavior in accordance with temperature were evaluated.
相似文献52.
Georgios Velkos Denis S. Krylov Kyle Kirkpatrick Lukas Spree Vasilii Dubrovin Bernd Büchner Stanislav M. Avdoshenko Valeriy Bezmelnitsyn Sean Davis Paul Faust James Duchamp Harry C. Dorn Alexey A. Popov 《Angewandte Chemie (International ed. in English)》2019,58(18):5891-5896
The azafullerene Tb2@C79N is found to be a single‐molecule magnet with a high 100‐s blocking temperature of magnetization of 24 K and large coercivity. Tb magnetic moments with an easy‐axis single‐ion magnetic anisotropy are strongly coupled by the unpaired spin of the single‐electron Tb?Tb bond. Relaxation of magnetization in Tb2@C79N below 15 K proceeds via quantum tunneling of magnetization with the characteristic time τQTM=16 462±1230 s. At higher temperature, relaxation follows the Orbach mechanism with a barrier of 757±4 K, corresponding to the excited states, in which one of the Tb spins is flipped. 相似文献
53.
Danilov D. V. Burmistrov V. V. Rasskazova E. V. Butov G. M. 《Russian Journal of Organic Chemistry》2020,56(6):983-989
Russian Journal of Organic Chemistry - A series of N-(4-oxoadamantan-1-yl)-N′-[fluoro(chloro)phenyl]ureas have been synthesized in 27–73% yields by reaction of... 相似文献
54.
Danilov D. V. Burmistrov V. V. Butov G. M. 《Russian Journal of Organic Chemistry》2020,56(7):1132-1139
Russian Journal of Organic Chemistry - Methods have been developed for the synthesis of N,N′-disubstituted ureas containing an adamantane fragment separated from the urea nitrogen atom by an... 相似文献
55.
Dr. Zhenghai Yang Dr. Srinivas Doddipatla Dr. Chao He Vladislav S. Krasnoukhov Prof. Dr. Valeriy N. Azyazov Prof. Dr. Alexander M. Mebel Prof. Dr. Ralf I. Kaiser 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(60):13584-13589
The silene molecule (H2SiCH2; X1A1) has been synthesized under single collision conditions via the bimolecular gas phase reaction of ground state methylidyne radicals (CH) with silane (SiH4). Exploiting crossed molecular beams experiments augmented by high-level electronic structure calculations, the elementary reaction commenced on the doublet surface through a barrierless insertion of the methylidyne radical into a silicon-hydrogen bond forming the silylmethyl (CH2SiH3; X2A′) complex followed by hydrogen migration to the methylsilyl radical (SiH2CH3; X2A′). Both silylmethyl and methylsilyl intermediates undergo unimolecular hydrogen loss to silene (H2SiCH2; X1A1). The exploration of the elementary reaction of methylidyne with silane delivers a unique view at the widely uncharted reaction dynamics and isomerization processes of the carbon–silicon system in the gas phase, which are noticeably different from those of the isovalent carbon system thus contributing to our knowledge on carbon silicon bond couplings at the molecular level. 相似文献
56.
Andreiy A. Gushchin Vladimir I. Grinevich Valeriy Ya. Shulyk Elena Yu. Kvitkova Vladimir V. Rybkin 《Plasma Chemistry and Plasma Processing》2018,38(1):123-134
The processes of degradation of 2,4-dichlorophenol (2,4-DCP) aqueous solutions under the action of atmospheric pressure of DBD in oxygen were studied. The degradation of 2,4-DCP proceeds efficiently, the degree of decomposition reaching 100%. The degradation kinetics of 2,4-DCP obeys a formal first-order kinetic law on concentration of 2,4-DCP. The effective rate constants depend weakly on the experimental conditions and are equal to ~ 2 s?1. Based on experimental data, the energy efficiency of 2,4-DCP decomposition was determined to be in the range of 0.039–0.173 molecules per 100 eV depending on the experimental conditions. The composition of the products was studied by gas chromatography, chromatography-mass spectrometry, UV/visible spectroscopy, fluorescent methods and some chemical methods. The main decomposition products present in the solution were found to be carboxylic acids, aldehydes and chloride ions, whereas carbon dioxide and molecular chlorine appear in the gas. The results obtained are compared with similar data from other advanced oxidation processes (AOP’s) methods. 相似文献
57.
Valeriy K. Bulitko 《Mathematical Logic Quarterly》2002,48(3):367-373
In this paper we consider the we known method by E. Post of solving the problem of construction of recursively enumerable sets that have a degree intermediate between the degrees of recursive and complete sets with respect to a given reducibility. Post considered reducibilities ≤m, ≤btt, ≤tt and ≤T and solved the problem for al of them except ≤T. Here we extend Post's original method of construction of incomplete sets onto two wide classes of sub‐Turing reducibilities what were studying in [1, 2]. 相似文献
58.
Vladimir V. Glushkov Alexey D. Bozhko Alexey V. Bogach Sergey V. Demishev Anatoliy V. Dukhnenko Volodimir B. Filipov Mikhail V. Kondrin Alexey V. Kuznetsov Ilia I. Sannikov Alexey V. Semeno Natalya Yu. Shitsevalova Valeriy V. Voronov Nikolay E. Sluchanko 《固体物理学:研究快报》2016,10(4):320-323
We report the study of transport and magnetic properties of the YbB6–δsingle crystals grown by inductive zone melting. A strong disparity in the low temperature resistivity, Seebeck and Hall coefficients is established for the samples with the different level of boron deficiency. The effective parameters of the charge transport in YbB6–δ are shown to depend on the concentration of intrinsic defects, which is estimated to range from 0.09% to 0.6%. The pronounced variation of Hall mobility μH found for bulk holes is induced by the decrease of transport relaxation time from τ ≈ 7.7 fs for YbB5.994 to τ ≈ 2.2 fs for YbB5.96. An extra contribution to conductivity from electrons with μH≈ –1000 cm2 V–1 s–1 and the very low concentration n /nYb≈ 10–6 discovered below 20 K for all the single crystals under investigation is suggested to arise from the surface electron states appeared in the inversion layer due to the band bending. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
59.
A. S. Demyanova T. L. Belyaeva A. N. Danilov Yu. A. Glukhov S. A. Goncharov S. V. Khlebnikov V. A. Maslov Yu. D. Molchanov Yu. E. Penionzkevich R. V. Revenko M. V. Safonenko Yu. G. Sobolev W. Trzaska G. P. Tyurin A. A. Ogloblin 《Physics of Atomic Nuclei》2009,72(10):1611-1616
We present new measurements of the α + 12C elastic and inelastic (to the states 4.44, 7.65, and 9.64 MeV) scattering at E lab = 110 MeV in the wide angular range from ~10° to 175°, which enable us to examine the condensate and cluster properties of the low-lying excited states in 12C. We present the diffraction-radius analysis of our data together with a considerable amount of the existing data. The magnitudes of the diffraction radii for the ground and the first excited (4.44 MeV) states are found to be equal, whereas they appear to be enhanced by ~0.6 fm both for 7.65 and 9.64 MeV states. This result shows that the radius of the Hoyle’s 0 2 + , 7.65 MeV state in 12C is by a factor of ~1.2–1.3 larger than that of the ground state. It is demonstrated that the direct transfer mechanism of 8Be dominates at the largest angles in all four reactions reported here. The configuration corresponding to the transfer of 8Be in its ground state (I π = 0+) with L = 0 turns out to be the most important for the 7.65 MeV state of 12C. Evidence of existence of some features of α-condensed structure of the Hoyle’s 0 2 + state in 12C was obtained: its enhanced radius and large contribution of α-particle configuration with L = 0. 相似文献
60.
S. V. Zaitsev I. A. Akimov L. Langer Yu. A. Danilov M. V. Dorokhin B. N. Zvonkov D. R. Yakovlev M. Bayer 《Journal of Experimental and Theoretical Physics》2016,123(3):420-428
The coherent spin dynamics of carriers in the heterostructures that contain an InGaAs/GaAs quantum well (QW) and an Mn δ layer, which are separated by a narrow GaAs spacer 2–10 nm thick, is comprehensively studied by the magnetooptical Kerr effect method at a picosecond time resolution. The exchange interaction of photoexcited electrons in QW with the ferromagnetic Mn δ layer manifests itself in magnetic-field and temperature dependences of the Larmor precession frequency of electron spins and is found to be very weak (several microelectron volts). Two nonoscillating components related to holes exist apart from an electron contribution to the Kerr signal of polarization plane rotation. At the initial stage, a fast relaxation process, which corresponds to the spin relaxation of free photoexcited holes, is detected in the structures with a wide spacer. The second component is caused by the further spin dephasing of energyrelaxed holes, which are localized at strong QW potential fluctuations in the structures under study. The decay of all contributions to the Kerr signal in time increases substantially when the spacer thickness decreases, which correlates with the enhancement of nonradiative recombination in QW. 相似文献