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151.
G.Yu. Golubiatnikov M.A. Koshelev A.F. Krupnov 《Journal of Molecular Spectroscopy》2003,222(2):191-197
Low pressure measurements of broadening parameters of the 118.75 GHz fine structure line of oxygen molecule have been made by a BWO-based spectrometer with acoustic detector (RAD) at room temperature. Pressure broadening parameters were obtained for the buffer gases O2, N2, Ne, He, Ar, H2O, CO2, and CO and have the following values 2.23 ± 0.01, 2.245 ± 0.02, 1.375 ± 0.02, 1.62 ± 0.03, 2.005 ± 0.02, 2.52 ± 0.04, 2.66 ± 0.08, and 2.31 ± 0.05 MHz/Torr, respectively. Measured central frequency is 118 750.340 ± 0.007 MHz. The central frequencies and broadenings by O2 and N2 of fine structure lines 1+, 5−, 7+, 11+, and 15− belonging to the 60-GHz band are also measured. Comparison of previous and recent data on electronic, rotational, and fine structure lines broadenings reveals their close values (within 10%) and dependencies on corresponding rotational quantum numbers for these different oxygen spectra stretching from millimeter through submillimeter up to the optical bands. Such similarity could be used for estimation of the broadenings of not measured yet oxygen lines. 相似文献
152.
Sergei V. Shirin Oleg L. Polyansky Nikolai F. Zobov Roman I. Ovsyannikov Jonathan Tennyson 《Journal of Molecular Spectroscopy》2006,236(2):216-223
Adiabatic potential energy surfaces (PESs) for three major isotopologues of water, H216O, H217O, and H218O, are constructed by fitting to observed vibration-rotation energy levels of the system using the nuclear motion program DVR3D employing an exact kinetic energy operator. Extensive tests show that the mass-dependent ab initio surfaces due to Polyansky et al. [O.L. Polyansky, A.G. Császár, S.V. Shirin, N.F. Zobov, P. Barletta, J. Tennyson, D.W. Schwenke, P.J. Knowles, Science 299 (2003) 539-542.] provide an excellent starting point for the fits. The refinements are performed using a mass-independent morphing function, which smoothly distorts the original adiabatic ab initio PESs. The best overall fit is based on 1788 experimental energy levels with the rotational quantum number J = 0, 2, and 5. It reproduces these levels with a standard deviation of 0.079 cm−1 and gives, when explicit allowance is made for nonadiabatic rotational effects, excellent predictions for levels up to J = 40. Theoretical linelists for all three isotopologues of water involved in the PES construction were calculated up to 26 000 cm−1 with energy levels up to J = 10. These linelists should make an excellent starting point for spectroscopic modelling and analysis. 相似文献
153.
Nitric acid (HNO3) plays an important role in the Earth’s atmosphere as a reservoir molecule of NOx species. It has a strong infrared signature at 11 μm which is one of the most commonly used for the infrared retrieval of this species in the atmosphere since this spectral region coincides with an atmospheric window. It is therefore essential to have high quality spectral parameters in this spectral region. For the H14NO3 (main) isotopic species, the 11 μm bands were already the subject of numerous extensive studies which involve not only the ν5 and 2ν9 cold bands but also the first hot bands. The present work is the first high resolution Fourier transform analysis of the 11 μm bands for H15NO3, which is the second most abundant isotopomer of nitric acid [a ≅ 0.00365(7)]. In this way, the analysis of the ν5 and 2ν9 cold bands centered at 871.0955 and 893.4518 cm−1 was performed, and as for H14NO3, these bands are significantly perturbed since rather strong resonances couple the 51 and 92 rotational levels. The theoretical model that we used to compute the line positions and line intensities is directly issued from the one which we used recently for H14NO3 [A. Perrin, J. Orphal, J.-M. Flaud, S. Klee, G. Mellau, H. Mäder, D. Walbrodt, M. Winnewisser, J. Mol. Spectrosc. 228 (2004) 375-391]. Actually, for the H15NO3 line positions, the Hamiltonian matrix accounts for the rather strong Fermi and the weaker Coriolis interactions linking the 51⇔92 rotational levels. Using this model which accounts correctly for the strong mixing of the 51 and 92 upper state energy levels, the ν5 and 2ν9 line intensities for H15NO3 were satisfactorily computed using the ν5 and 2ν9 transition moment operators achieved previously for the 14N (main) isotopic species. In this way, the transfer of intensities from the ν5 fundamental (and presumably strong) band to the 2ν9 overtone (and presumably weak) band could be explained for H15NO3 as it was done previously for the 14N (main) isotopic species. Finally, the position of the H15NO3ν5 + ν9 − ν9 hot band was identified at 875.245 cm−1. 相似文献
154.
D. Boudjaadar V. Dana G. Guelachvili X. Thomas 《Journal of Molecular Spectroscopy》2006,238(1):108-117
Using Fourier-transform spectra and a multispectrum fitting procedure, 124 absolute line intensities of 12C16O2 are obtained for the cold band 30011-00001 and the hot band 01131-01101 between 6460 and 6950 cm−1. Vibrational transition dipole moments squared and Herman-Wallis coefficients are reported for each band. Cross comparisons made with previous experimental results and with data available in the HITRAN and Carbon Dioxide Spectroscopic Databank (CDSD), bring some confidence on the good level of accuracy of the present results. Motivated by the demanding needs of some atmospheric experiments dedicated to the survey of the carbon cycle, an additional evaluation of potential absolute line intensity measurement limit is also performed on recently published carbon dioxide absolute line intensity independent measurements. These are obtained in two different laboratories on the bands 30013-00001 and 30012-00001 both located in the 1.6 μm spectral window. It is shown that Fourier-transform experimental CO2 line intensity determination is approaching the challenging required figure of about 0.3% accuracy needed for the survey of the atmospheric carbon cycle. 相似文献
155.
本文从理论,实验上论证了“马氏(红移)定律”,同时指出所谓“退行速度Vr”或“星系红移”与“星系间的距离”无必须的关系,从这个意义上来说,哈勃定律是错误的。 相似文献
156.
本文采用顺序等离子体光谱技术测定煤飞灰中主要成份(Ca、Mg、Fe、Al、Si、Na、K、Ti)及微量成份(Cu、Sc、V、Ni、Be、Mn)。用扫描光谱法研究了分析线的选择和光谱背景的扣除。试样用密封罐混酸溶解。测定煤飞灰标准样品NBS1633a的结果与标准值一致。方法用于测定新制备的煤飞灰标准参考物。 相似文献
157.
利用谱线宽度测人发中的微量元素 总被引:2,自引:0,他引:2
通过实验证明了可以利用谱线宽度做永久工作曲线用于光谱定量分析。给出了用于测量人发中微量元素Cu,Zn,Fe和Ca的永久工作曲线,利用这些工作曲线对实际样品进行了测定,所得结果与用ICP-AES测得的结果相吻合。 相似文献
158.
159.
160.
利用多道光学分析仪测量Hα线形分布,从线形的分布推出再循环的氢原子主要来源于离子中性化后的反射和氢分子的离解。通过双高斯拟合Hα线形分布,由多普勒频移得出了氢原子的入射速度。从氢原子能量分布上的特征峰得出氢分子的离解方式主要是电离和直接离解。 相似文献