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881.
We relate the entropies of ensembles of atoms in optical lattices to atoms in simple traps. We then determine which ensembles of lattice-bound atoms will adiabatically transform into a Bose condensate. This shows a feasible approach to Bose condensation without evaporative cooling. 相似文献
882.
Reaction of Rh(I) and Zn(II) metal centers with a ligand containing salicylaldiminato and thioether-phosphine moieties resulted in the formation of a tetranuclear heterobimetallic molecular square. The directionality required to form these structures is imparted by both the tetrahedral and square planar metal centers acting in concert with one another. 相似文献
883.
V. M. Antonov Yu. P. Zakharov A. V. Melekhov V. N. Oraevskii A. G. Ponomarenko V. G. Posukh 《Journal of Applied Mechanics and Technical Physics》2001,42(6):949-958
Experiments using a powerful CO2 amplifier were performed with the aim of developing a technique for simulating a space explosion in the magnetosphere of the Earth and other planets under laboratory conditions using laser plasma clouds. The amplifier radiation with an energy of about 300 J and a pulse duration of about 10–7 sec focused on a Caprolon target of 4 mm diameter produced an exploding plasma in a dipole magnetic field with a characteristic dimension of 15 cm and a magnetic moment of 1.1·107 Gs · cm3. The paper presents preliminary results of simulating a space explosion under quasitrapping conditions, where the energy of the explosion is much lower than the geomagnetic energy and the explosion point is located in the equatorial plane at a distance of two Earth's radii. 相似文献
884.
The molecular dynamics (MD) simulation, based on a realistic atom-atom interaction potential, was performed on 4-n-pentyl-4'-cyanobiphenyl (5CB) in the nematic phase. The rotational viscosity coefficients (RVCs) γ
i, (i = 1, 2) and the ratio of the RVCs λ = - γ
2/γ
1 were investigated. Furthermore, static and frequency-dependent dielectric constants and ε were calculated using parameters obtained from the MD simulation. Time correlation functions were computed and used to determine
the rotational diffusion coefficient, D
⊥. The RVCs and λ were evaluated using the existing statistical-mechanical approach (SMA), based on a rotational diffusion
model. The SMA rests on a model in which it is assumed that the reorientation of an individual molecule is a stochastic Brownian
motion in a certain potential of mean torque. According to the SMA, γ
i are dependent on the orientational order and rotational diffusion coefficients. The former was characterized using: i) orientational
distribution function (ODF), and ii) a set of order parameters, both derived from analyses of the MD trajectory. A reasonable
agreement between the calculated and experimental values of γ
i and λ was obtained.
Received 22 March 2000 and Received in final form 8 October 2000 相似文献
885.
Daniel T. Seidenkranz Kurt A. Langworthy Lev N. Zakharov 《Supramolecular chemistry》2019,31(8):499-507
ABSTRACTWe report here the first chiral barbiturate to act as a single-component LMOG capable of gelating a variety of chlorinated and aromatic solvents. Solution-based DOSY NMR experiments, solid-state VP-SEM, and X-ray crystallography techniques were used to characterize chloroform-based gels at a variety of size domains. This scaffold provides a simple system to study the dynamics of gelation and self-assembly. 相似文献
886.
Dr. Pavel A. Petrov Evgeny M. Kadilenko Dr. Taisiya S. Sukhikh Dr. Ilia V. Eltsov Prof. Artem L. Gushchin Prof. Vladimir A. Nadolinny Prof. Maxim N. Sokolov Prof. Nina P. Gritsan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(64):14688-14699
Interaction of the tetradentate redox-active 6,6′-[1,2-phenylenebis(azanediyl)]bis(2,4-di-tert-butylphenol) (H4L) with TeCl4 leads to neutral diamagnetic compound TeL ( 1 ) in high yield. The molecule of 1 has a nearly planar TeN2O2 fragment, which suggests the formulation of 1 as TeIIL2−, in agreement with the results of DFT calculations and QTAIM and NBO analyses. Reduction of 1 with one equivalent of [CoCp2] leads to quantitative formation of the paramagnetic salt [CoCp2]+[ 1 ].−, which was characterised by single-crystal XRD. The solution EPR spectrum of [CoCp2]+[ 1 ].− at room temperature features a quintet due to splitting on two equivalent 14N nuclei. Below 150 K it turns into a broad singlet line with two weak satellites due to the splitting on the 125Te nucleus. Two-component relativistic DFT calculations perfectly reproduce the a(14N) HFI constants and A∥(125Te) value responsible for the low-temperature satellite splitting. Calculations predict that the additional electron in 1 .− is localised mainly on L, while the spin density is delocalised over the whole molecule with significant localisation on the Te atom (≥30 %). All these data suggest that 1 .− can be regarded as the first example of a structurally characterised monomeric tellurium–nitrogen radical anion. 相似文献
887.
888.
A. A. Radkovskaya G. S. Pal’vanova E. I. Lebedeva V. N. Prudnikov O. A. Kotel’nikova P. N. Zakharov A. F. Korolev 《Bulletin of the Russian Academy of Sciences: Physics》2013,77(12):1401-1406
Results from an experimental study of the interaction between elements of discrete magnetic metamaterials in the GHz range, depending on the mutualorientation of meta-atoms in the same plane, are presented. The increased complexity of the mechanism of interaction between meta-atoms is discussed for when the size of the elements is reduced as optical frequencies are approached. 相似文献
889.
In this note we recast the Geronimus transformation in the framework of polynomials orthogonal with respect to symmetric bilinear forms. We also show that the double Geronimus transformations lead to non-diagonal Sobolev type inner products. 相似文献
890.