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51.
Several bands of nitrous oxide occurring in the region of about 5.3 μm have been measured by using a high resolution vacuum infrared spectrograph. The molecular constants derived from the data have been given along with the basic data. 相似文献
52.
J.-M. Flaud C. Camy-Peyret K. Narahari Rao Da-Wun Chen Yan-Shek Hoh J.-P. Maillard 《Journal of Molecular Spectroscopy》1979,75(3):339-362
Measurements of the line positions of H216O in the 8050 to 9370 cm?1 region have been performed at a spectral resolution of 0.07 cm?1. A grating spectrum of room-temperature water vapor and a Fourier transform spectrum of heated water vapor (T ? 60°C) were used in the interpretation. A careful analysis of the bands ν1 + 3ν2, 3ν2 + ν3, 2ν1 + ν2, ν1 + ν2 + ν3, and ν2 + 2ν3 has led to a set of rotational levels belonging to the vibrational states (130), (031), (210), (111), and (012). Many vibrorotational resonances were detected. 相似文献
53.
54.
Extensive computations were performed on aqueous clusters of monovalent sodium cation [Na+(H2O) n ; (n = 1–20)] using MP2/cc-pVTZ and density functional theory. The structure, energy, and coordination number (CN) preference of a large number of competing conformations of different complexes have been explored. For complexes up to n = 12, the CN 4 is most preferred while 5, 6 CNs are favored in case of larger complexes containing up to 20 water molecules. These results are in very good agreement with experimental observations. The strength of hydrogen bonding among the waters coordinated to the Na+ ion is found to play a major role in the stability of the complexes. The varying preferences for CN of Na+ ion were explored by screening two important databases: Protein Databank and Cambridge Structural Database. A linear correlation is observed between the M (Metal)–O distance and the charge on metal ion in complex with the increase in CN of metal ion. 相似文献
55.
56.
Fork-join queueing systems offer a natural modelling paradigm for parallel processing systems and for assembly operations in automated manufacturing. The analysis of fork-join queueing systems has been an important subject of research in recent years. Existing analysis methodologies—both exact and approximate—assume that the servers are failure-free. In this study, we consider fork-join queueing systems in the presence of server failures and compute the cumulative distribution of performability with respect to the response time of such systems. For this, we employ a computational methodology that uses a recent technique based on randomization. We compare the performability of three different fork-join queueing models proposed in the literature: the distributed model, the centralized splitting model, and the split-merge model. The numerical results show that the centralized splitting model offers the highest levels of performability, followed by the distributed splitting and split-merge models. 相似文献
57.
58.
V. Malathy Devi P.P. Das K. Narahari Rao Š. Urban D. Papoušek V. Špirko 《Journal of Molecular Spectroscopy》1981,88(2):293-299
The spectra of the ν2 bands of 14ND3 and 15ND3 were measured under Doppler-limited resolution with a diode laser spectrometer in order to resolve the K structure of the sR(J, K) and aR(J, K) multiplets. By a simultaneous least-squares analysis of these data, the Fourier spectra of the ν2 band measured by Jones [J. Mol. Spectrosc.74, 409 (1979)], and the ground-state microwave transitions, sets of improved ν2-band parameters were obtained, including the sextic centrifugal distortion coefficients. 相似文献
59.
A new method for the determination of the constant A0 in symmetric top molecules is proposed. This method utilizes the data for the overtone bands of a doubly degenerate vibration of symmetry species E1u. Transitions necessary for the determination of A0 have been indicated for all symmetric top symmetry groups. The precision of A0 values determined according to the method suggested is also discussed. 相似文献
60.
L. Henry A. Valentin W. J. Lafferty J. T. Hougen V. Malathy Devi P. P. Das K. Narahari Rao 《Journal of Molecular Spectroscopy》1983,100(2):260-289
Fourier transform measurements with an apodized apparatus function up to 0.002 cm−1 are reported for the ν9 band (ρu) of ethane in the 12-μm region, together with an integrated band strength obtained from intensity measurements on selected Q-branch lines recorded using a diode laser spectrometer. Since the ν9 band falls in an atmospheric window, these data may be useful in studies of the ethane concentration in the atmosphere of Jupiter and other outer planets. Torsional splittings in the ν9 level caused by a higher-order Coriolis interaction with the close lying 3ν4 state (a1u) have been analyzed in a global least squares fit of 2206 Fourier transform lines and 58 diode splittings to a molecular Hamiltonian containing 20 parameters, with a standard deviation of 0.35 × 10−3 cm−1. Rotational levels of one component of the torsionally split 3ν4 state cross interacting rotational levels of the ν9 state for K = 17, and the spectrum is followed to K = 19 on the pP subband side to permit inclusion of ν9 levels beyond this crossing. No transitions to 3ν4 levels were observed. The theoretical treatment presented here makes use of standard symmetric top formalism and of the G36† double-group formalism for ethane. 相似文献