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41.
Kaplan L Heller EJ 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,59(6):6609-6628
The phenomenon of periodic orbit scarring of eigenstates of classically chaotic systems is attracting increasing attention. Scarring is one of the most important "corrections" to the ideal random eigenstates suggested by random matrix theory. This paper discusses measures of scars and in so doing also tries to clarify the concepts and effects of eigenfunction scarring. We propose a universal scar measure which takes into account an entire periodic orbit and the linearized dynamics in its vicinity. This measure is tuned to pick out those structures which are induced in quantum eigenstates by unstable periodic orbits and their manifolds. It gives enhanced scarring strength as measured by eigenstate overlaps and inverse participation ratios, especially for longer orbits. We also discuss off-resonance scars which appear naturally on either side of an unstable periodic orbit. 相似文献
42.
G. W. A. Milne W. L. Budde S. R. Heller D. P. Martinsen R. G. Oldham 《Journal of mass spectrometry : JMS》1982,17(11):547-552
Over 1400 electron ionization mass spectra of selected organic compounds have been measured under carefully defined conditions. In this paper, the variables such as sample purity and spectrometer calibration that are controlled are described. The quality of the resulting spectra as well as the cost of the measurements is reported. 相似文献
43.
Wilfried Heller Ellen Shirley E. Schwartz 《Journal of Polymer Science.Polymer Physics》1972,10(10):1903-1915
The theory of an interferometric method for determining partial specific volumes of macromolecules is briefly reviewed. The experimental technique developed in this laboratory is described. Detailed results are given on the partial specific volume of ovalbumin in aqueous solution and its dependence on pH and KCl concentration. The results are compared, as far as possible, with dilatometric results obtained in another laboratory. The contribution of a change in partial specific volume of the macromolecules and in the partial specific volume of the water associated with them to the results is analyzed, and the scope of a possible complication due to changes in molecular polarizability is pointed out. 相似文献
44.
Progress in the development of the NIH—EPA chemical information system is reviewed. 相似文献
45.
Abstract— A methodology for the determination of chemiluminescence quenching terms is given. By using the oxidation of tetrakis(dimethylamino)ethylene as an example, it is shown how the nature and magnitude of the quenching terms help to elucidate the reaction mechanism, or how ignoring them can lead to false impressions. It is shown that chemiluminescence quenching effects need not be the same as those for photoluminescence of the same electronically excited species. 相似文献
46.
The rheological behavior of an elastomer composed of a polyurethane rubber filled with granular potassium chloride is studied on the basis of a series of compression tests with superimposed hydrostatic pressure. It is suggested that behavior may be approximated by a linear anelastic response for relatively small strains until a marked change in structure occurs, and that further deformation involves shear-dependent dilatation which is strongly influenced by mean pressure. Theories are suggested which describe the experimentally observed behavior. 相似文献
47.
Aubin C Bernard C Detar C Di Pierro M Freeland ED Gottlieb S Heller UM Hetrick JE El-Khadra AX Kronfeld AS Levkova L Mackenzie PB Menscher D Maresca F Nobes M Okamoto M Renner D Simone J Sugar R Toussaint D Trottier HD;Fermilab Lattice Collaboration;MILC Collaboration;HPQCD Collaboration 《Physical review letters》2005,95(12):122002
We present the first lattice QCD calculation with realistic sea quark content of the D+-meson decay constant f(D+). We use the MILC Collaboration's publicly available ensembles of lattice gauge fields, which have a quark sea with two flavors (up and down) much lighter than a third (strange). We obtain f(D+)=201+/-3+/-17 MeV, where the errors are statistical and a combination of systematic errors. We also obtain f(Ds)=249+/-3+/-16 MeV for the Ds meson. 相似文献
48.
O2 was electroreduced to water, at a true-surface-area-based current density of 0.5 mA cm-2, at 37 degrees C and at pH 5 on a "wired" laccase bioelectrocatalyst-coated carbon fiber cathode. The polarization (potential vs the reversible potential of the O2 /H2O half-cell in the same electrolyte) of the cathode was only -0.07 V, approximately one-fifth of the -0.37 V polarization of a smooth platinum fiber cathode, operating in its optimal electrolyte, 0.5 M H2SO4. The bioelectrocatalyst was formed by "wiring" laccase to carbon through an electron conducting redox hydrogel, its redox functions tethered through long and flexible spacers to its cross-linked and hydrated polymer. Incorporation of the tethers increased the apparent electron diffusion coefficient 100-fold to (7.6 +/- 0.3) x 10-7 cm 2 s-1. A miniature single-compartment glucose-O2 biofuel cell made with the novel cathode operated optimally at 0.88 V, the highest operating voltage for a compartmentless miniature fuel cell. 相似文献
49.
50.
Fiete GA Hersch JS Heller EJ Manoharan HC Lutz CP Eigler DM 《Physical review letters》2001,86(11):2392-2395
We explain the origin of the Kondo mirage seen in recent quantum corral scanning tunneling microscope experiments with a scattering theory of electrons on the surfaces of metals. Our theory, combined with experimental data, provides a direct observation of a single Kondo atom phase shift. The Kondo mirage observed at the empty focus of an elliptical quantum corral is shown to arise from multiple electron bounces off the corral wall adatoms. We demonstrate our theory with direct quantitive comparison to experimental data. 相似文献