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排序方式: 共有182条查询结果,搜索用时 15 毫秒
101.
Yunjing Li Meirong Lin Wenli Zou Baozheng Zhang Wenju Chen 《Molecular physics》2013,111(17):1365-1367
The laser-induced fluorescence spectra of the InCl molecule over the range 266.5–287.0nm and 332.0–373.0nm are reported and assigned to C1Π1-X1Σ+, B3Π1-X1Σ+, or A3Π0-X1Σ+ transitions. It is the first time those radiative lifetimes of the C1Π1 and B3Π1 states have been measured by laser-induced fluorescence. The collision-free fluorescence radiative lifetime τ0 = 353(7)ns and a quenching rate constant k Q = 1.985(0.010)x 10-10 cm3 molecule-1 s-1 are proposed for B3Π1 and τ0 = 11(1)ns for C1Π1 states. From the radiative lifetime τ0 and the Franck-Condon factors qv″v′ for the v′ - v″ transitions, the electronic transition moments |Re|2 of the B3Π1 and C1Π1 states have been obtained. 相似文献
102.
亚铁离子对驱油聚合物溶液黏度的影响及其降黏机理 总被引:1,自引:0,他引:1
采用NaOH沉淀法去除胜坨油田T28区污水含有的亚铁离子(Fe2+),使配制的聚合物溶液黏度增加,通过红外光谱仪(IR)、荧光光谱仪及扫描电子显微镜(SEM)对Fe2+的降黏机理进行了分析。 结果表明,采用NaOH沉淀法处理Fe2+含量为5.9 mg/L的污水,控制pH=9,聚合物溶液的黏度可由19.17 mPa·s提高到92.50 mPa·s。 Fe2+使聚合物大分子发生断链,分子间的缔合作用减弱,破坏了分子链间形成的空间网络结构,导致溶液黏度显著降低;当用NaOH处理Fe2+后形成了Fe(OH)2沉淀而析出,同时使聚合物分子链间形成致密的空间网络结构。 相似文献
103.
104.
105.
Spatial beam shaping by quartz crystal piano-convex lens 总被引:1,自引:0,他引:1
Based on the optical activity of quartz crystal, we proposed a scheme for shaping the spatial intensity distribution of a linearly polarized laser beam by utilizing a quartz crystal piano-convex lens in combination with a polarizer. The intensity profile of the shaped laser beam can be easily switched from one profile to another by controlling the polarization direction of the incident laser beam. 相似文献
106.
Bai Zhen Wang Qi Xu Hushan Wang Meng Wang Jiansong Hu Zhengguo Han Jianlong Chen Ruofu Zhang Xueyin Sun Zhiyu Tu Xiaolin Yue Ke Yang Yanyun Yao Xiangwu Huang Meirong Tang Bin Zhang Yapeng Zhang Xueheng Wu Dapeng Qiu Hao Chin Jinda Zang Yongdong Li Dehui Zhang Jie Xu Zhiguo Xiao Guoqing 《近代物理研究所和兰州重离子加速器实验室年报》2007,(1)
107.
108.
Determining the nuclear temperature dependence on source neutron-proton asymmetry in heavy-ion reactions at intermediate energy 下载免费PDF全文
Guofeng Qu Yu Huang Hua Zheng Xingquan Liu R. Wada Weiping Lin Meirong Huang Jifeng Han Peipei Ren Zhenlei Yang Xin Zhang Qiangzhong Leng 《中国物理C(英文版)》2023,47(5):054002-054002-8
In this article, we investigate the dependence of nuclear temperature on emitting source neutron-proton (\begin{document}$ N/Z $\end{document} ![]()
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) asymmetry with light charged particles (LCPs) and intermediate mass fragments (IMFs) generated from intermediate-velocity sources in thirteen reaction systems with different \begin{document}$ N/Z $\end{document} ![]()
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asymmetries, \begin{document}$ ^{64} \rm{Zn} $\end{document} ![]()
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on \begin{document}$ ^{112} \rm{Sn} $\end{document} ![]()
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, and \begin{document}$ ^{70} \rm{Zn} $\end{document} ![]()
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, \begin{document}$ ^{64} \rm{Ni} $\end{document} ![]()
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on \begin{document}$ ^{112,124} \rm{Sn} $\end{document} ![]()
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, \begin{document}$ ^{58,64} \rm{Ni} $\end{document} ![]()
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, \begin{document}$ ^{197} \rm{Au} $\end{document} ![]()
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, and \begin{document}$ ^{232} \rm{Th} $\end{document} ![]()
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at 40 MeV/nucleon. The apparent temperature values of LCPs and IMFs from different systems are deduced from the measured yields using two helium-related and eight carbon-related double isotope ratio thermometers, respectively. Then, the sequential decay effect on the experimental apparent temperature deduction with the double isotope ratio thermometers is quantitatively corrected explicitly with the aid of the quantum statistical model. The present treatment is an improvement compared to our previous studies in which an indirect method was adopted to qualitatively consider the sequential decay effect. A negligible \begin{document}$ N/Z $\end{document} ![]()
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asymmetry dependence of the real temperature after the correction is quantitatively addressed in heavy-ion reactions at the present intermediate energy, where a change of 0.1 units in source \begin{document}$ N/Z $\end{document} ![]()
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asymmetry corresponds to an absolute change in temperature of an order of 0.03 to 0.29 MeV on average for LCPs and IMFs. This conclusion is in close agreement with that inferred qualitatively via the indirect method in our previous studies. 相似文献
109.
This paper deals with the existence of positive solutions for the nonlinear system
. This system often arises in the study of positive radial solutions of nonlinear elliptic system. Here u = (u
1, …, u
n) and f
i, i = 1, 2, …, n are continuous and nonnegative functions, p(t), q(t): [0, 1] → (0, ∞) are continuous functions. Moreover, we characterize the eigenvalue intervals for
. The proof is based on a well-known fixed point theorem in cones. 相似文献
110.
This paper aimed at studying chiral symmetry-breaking phenomena in one crystal. Preferential crystallization of racemic asparagines was carried out in nonseeded stagnant solutions through slow cooling. By varying the supersaturation, only one transparent crystal could be obtained at enough low supersaturation of dl-asparagine, and the crystal was not pure enantiomer with crystal enantiomeric excess increasing inversely with the degree of supersaturation. Crystal enantiomeric excess can amount up to 85% in one transparent crystal. Because no secondary nucleation occurred except for stochastic primary nucleation, we suggest that primary nucleation and competition between l- and d-nuclei were considered to be a mechanism for asymmetry amplification. High-performance capillary electrophoresis coupled with laser-induced fluorescence was used to separate and quantify l- and d-asparagine and the enantiomeric excess value can be calculated according to their concentration. 相似文献