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91.
We have calculated the eigenvalue trajectories of the scattering kernel for a system of three, identical particles with Yamaguchi interactions, for both spin half and spin zero particles. For potential strengths corresponding to large values of the two-body scattering length, we find several, weakly-bound, three-body excited states of the type proposed by Efimov, and calculate their binding energies. 相似文献
92.
Fausto Ramirez Panayiotis V. Ioannou James F. Marecek George H. Dodd Bernard T. Golding 《Tetrahedron》1977,33(6):599-608
A new method for the synthesis of the cardiolipin family of phospholipids which are characteristically located at the inner membrane of mitochondria, and particularly abundant in the heart, is described in this paper. A 1,2-diacyl-sn-glycerol, derived from stearic, palmitic, or myristic acid, is converted into the corresponding 1',3'-diphosphatidylglycerol (DPG), by means of the phosphorylating reagent di(1,2-dimethylethenylene) pyrophosphate in 29%, 23% and 25% overall yields, respectively. The synthesis involves four steps, two of which are carried out in one-flask; only one intermediate and the final product, DPG·2NH4+·2H2O, are purified, the former by silica gel, and the latter by DEAE-cellulose column chromatography. The ammonium salts are converted into metal ion salts, DPG·2Na+· 2H2O, DPG·Mg2+ 2H2O and DPG·Ca2+·2H2O by metathesis with NaCl, MgCl2 and CaCl2, respectively. 相似文献
93.
94.
Dodd ES Hemker RG Huang CK Wang S Ren C Mori WB Lee S Katsouleas T 《Physical review letters》2002,88(12):125001
This Letter examines the electron-hosing instability in relation to the drivers of current and future plasma-wakefield experiments using fully three-dimensional particle-in-cell simulation models. The simulation results are compared to numerical solutions and to asymptotic solutions of the idealized analytic equations. The measured growth rates do not agree with the existing theory and the behavior is shown to depend sensitively on beam length, shape, and charge. We find that even when severe hosing occurs the wake can remain relatively stable. 相似文献
95.
The separation of arylarsonic acids by HPLC on a reverse-phase C18 column is described. Solutions containing these arsenicals and others such as arsenobetaine are photo-oxidized to arsenate by ultraviolet (UV) radiation (1200 W, 1 h exposure). This allows the analysis of the solution for arsenic by hydride generation techniques. The method, UV HGAA, is developed and applied to the determination of arsenic in the methanol extracts of the Manila clam (Verupis japonica) and the Horse clam (Schizothoerus nutalli). 相似文献
96.
A convergent synthetic approach is outlined to the tricyclic compound , which contains the full carbon skeleton of olivin. 相似文献
97.
Phase incremented and continuous irradiation multiple spin correlation methods are applied to spin [Formula: see text] nuclei with small quadrupole couplings such as (7)Li in LiCl and are shown to successfully produce a coherently coupled dipolar spin network. Application to the analogous Na salt shows successful spin correlation evolving at a slower rate due to the weaker homonuclear dipolar coupling strength between Na nuclei. The results are analysed using a statistical approach. Spin counting is non-trivial as not only multiple quantum coherences between spins are generated but also within the quadrupolar spin levels. Na(2)C(2)O(4) is investigated as a material with non-negligible quadrupole coupling and it is in this limit that the spin correlation techniques are found to break down. 相似文献
98.
Doros N. Theodorou Travis D. Boone Lawrence R. Dodd Kevin F. Mansfield 《Macromolecular theory and simulations》1993,2(2):191-238
The calculation of the stress tensor from molecular simulations of atomistic model polymer systems employing periodic boundary conditions is discussed. Starting from the dynamical equations governing the motion of sites, correct double summation forms of the atomic and the molecular virial equations are derived, which are valid for flexible, infinitely stiff and rigid chain models even in the presence of interactions between different images of the same parent macromolecule. A new expression for the true instantaneous stress (flux of momentum through the faces of the simulation box) is derived and shown to exhibit large fluctuations when applied in molecular dynamics simulations. A new equation for the thermodynamic stress, cast exclusively in terms of intermolecular forces on interaction sites, is also derived. Application to Monte Carlo simulations shows that the molecular virial expression exhibits the smallest fluctuations among all stress expressions discussed, and thus allows computation of the thermodynamic stress with least uncertainty. A scheme is developed for the calculation of surface tension from intermolecular forces only. 相似文献
99.
A. H. Dodd 《Fresenius' Journal of Analytical Chemistry》1933,92(3-4):160
Ohne Zusammenfassung 相似文献
100.