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71.
B. Roussière E. Le Blanc G. Savard H. T. Duong J. Pinard S. Liberman J. K. P. Lee J. E. Crawford G. Thekkadath P. Kilcher J. Obert J. Oms J. C. Putaux J. Sauvage ISOCELE Collaboration 《Hyperfine Interactions》1988,43(1-4):473-476
Isotope shift (IS) and hyperfine structure (HFS) measurements have been performed for185, 187, 189, 191, 195Pt using the PILIS (Post ISOCELE Laser Isobar Separator) apparatus installed at the ISOCELE facility. Magnetic and quadrupole
moments have been deduced from the HFS results. The charge radius changes determined for these odd nuclei from the IS results,
added to the σ<r2> values of the even-A nuclei are compared to the results of lattice Hartree-Fock+BCS calculations for asymmetric solutions:185Pt is confirmed to be prolate shaped whereas187, 189, 191Pt are likely triaxial in their ground states. 相似文献
72.
V. E. Dudkin E. E. Kovalev N. A. NefedovV. A. Antonchik S. D. Bogdanov V. I. OstroumovE. V. BentonH. J. Crawford 《Nuclear Physics A》1991,530(3-4):759-769
Nuclear photographic emulsion is used to study the dependence of the characteristics of target-nucleus fragments on the masses and impact parameters of interacting nuclei. The data obtained are compared in all details with the calculation results made in terms of the Dubna version of the cascade-evaporation model (DCM). 相似文献
73.
74.
H. Gabelmann J. Münzel B. Pfeiffer G. I. Crawford H. Wollnik K. -L. Kratz 《Zeitschrift für Physik A Hadrons and Nuclei》1982,308(4):359-360
Beta-delayed neutron emission probabilities (Pn) of short-lived Sr, Y, Ba and La precursors were measured. As expected from systematics, but in disagreement with recent data from the SOLIS-group, only small Pn -values were obtained. 相似文献
75.
The hydrogen vibrational modes in LaHx samples have been investigated by pulsed neutron spectroscopy. The results are compared with a simple model emphasizing strong HH forces and the lack of stoichiometry in LaH2.28. 相似文献
76.
B. Roussière F. Le Blanc J. Pinard L. Cabaret J. Crawford H. T. Duong J. Genevey G. Huber F. Ibrahim M. Krieg J. K. P. Lee J. Obert J. Oms J. C. Putaux C. Richard-Serre J. Sauvage V. Sebastian 《Acta Physica Hungarica A》1998,7(1):97-100
Isotope shift and hyperfine structure measurements have been performed on the short lived184Au nucleus using the COMPLIS apparatus installed at ISOLDE. The charge radius change and the magnetic and quadrupole moments of both isomeric and ground states have been deduced. The184Au ground state appears to be slightly more deformed than the isomeric state. 相似文献
77.
K. -L. Kratz H. Ohm H. Gabelmann G. I. Crawford G. Jung B. Pfeiffer 《Zeitschrift für Physik A Hadrons and Nuclei》1982,305(1):93-94
Beta-delayed neutron measurements on95Rb have indicated evidence for two heretofore unknown excited O+ states in94Sr which are not fed by ß -decay from the Jπ = 3? ground state of94Rb. 相似文献
78.
79.
Tasić U Alexeev Y Vayner G Crawford TD Windus TL Hase WL 《Physical chemistry chemical physics : PCCP》2006,8(40):4678-4684
Ab initio calculations at the CCSD(T)/aug-cc-pVTZ level of theory were used to characterize the Ar-CH(3)OH intermolecular potential energy surface (PES). Potential energy curves were calculated for four different Ar + CH(3)OH orientations and used to derive an analytic function for the intermolecular PES. A sum of Ar-C, Ar-O, Ar-H(C), and Ar-H(O) two-body potentials gives an excellent fit to these potential energy curves up to 100 kcal mol(-1), and adding an additional r(-n) term to the Buckingham two-body potential results in only a minor improvement in the fit. Three Ar-CH(3)OH van der Waals minima were found from the CCSD(T)/aug-cc-pVTZ//MP2/aug-cc-pVTZ calculations. The structure of the global minimum is in overall good agreement with experiment (X.-C. Tan, L. Sun and R. L. Kuczkowski, J. Mol. Spectrosc., 1995, 171, 248). It is T-shaped with the hydroxyl H-atom syn with respect to Ar. Extrapolated to the complete basis set (CBS) limit, the global minimum has a well depth of 0.72 kcal mol(-1) with basis set superposition error (BSSE) correction. The aug-cc-pVTZ basis set gives a well depth only 0.10 kcal mol(-1) smaller than this value. The well depths of the other two minima are within 0.16 kcal mol(-1) of the global minimum. The analytic Ar-CH(3)OH intermolecular potential also identifies these three minima as the only van der Waals minima and the structures predicted by the analytic potential are similar to the ab initio structures. The analytic potential identifies the same global minimum and the predicted well depths for the minima are within 0.05 kcal mol(-1) of the ab initio values. Combining this Ar-CH(3)OH intermolecular potential with a potential for a OH-terminated alkylthiolate self-assembled monolayer surface (i.e., HO-SAM) provides a potential to model Ar + HO-SAM collisions. 相似文献
80.
Coupled-cluster and density-functional methods have been used to determine specific rotations and electronic circular dichroism (ECD) rotational strengths for (S)-2-chloropropionitrile. Coupled-cluster specific rotations using both the length- and velocity-gauge representations of the electric-dipole operator, computed with basis sets of triple-zeta quality containing up to 326 functions, compare very well with recently reported gas-phase cavity-ring-down polarimetry data. ECD rotational strengths for the six lowest-lying excited states are found to vary in sign, and the second excited state, which has a larger rotational strength than the first by a factor of 4, was found to yield a much larger contribution (by a factor of 10) to the overall negative specific rotation observed both experimentally and theoretically. However, both valence and Rydberg states appear to make substantial contributions to the total rotation, often of opposite sign from the converged/linear-response result. Furthermore, the sum-over-states approach was found to be inadequate for reproducing the specific rotations derived from the linear-response approach, even when 100 excited states (well beyond the estimated ionization limit) were included in the summation. Density-functional specific rotations using the B3LYP functional with basis sets of quadruple-zeta quality containing up to 588 functions are found to be too large compared to experiment by approximately a factor of 2. This error appears to be related to both the underestimation of the electronic excitation energies, as well as concomitant overestimation of the corresponding ECD rotational strengths. Although earlier studies reported good agreement between density-functional specific rotations and experiment when electric-field-dependent functions were used in conjunction with a double-zeta-quality basis set, the results reported here, which are near the basis-set limit, suggest that this agreement may be fortuitous. 相似文献