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101.
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  
黄漫  李美蓉  田兰兰  黄银  马宝东  刘坤 《应用化学》2013,30(12):1399-1403
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.
吴美容  孙浩  陈辉 《运筹学学报》2014,18(2):119-125
介绍了能准确刻画现实生活中每个参与者有三种选择的双合作对策,在此基础上研究了双合作对策的\tau值,并对双准均衡合作对策的\tau值进行了公理化,其中双合作对策的上向量、间隙函数、让步向量的构造是刻画其\tau值的基础.  相似文献   
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.
107.
贴片散斑法将一种可剥离铝箔贴附在试件表面,经随机划痕制栅后,以其精细的光学结构和高度的反射本领,在白光或激光照射下,表面辐射率随机分布函数作为散斑场,采取直接记录手段,用全息底片对此作物体变形前后的两次曝光,所得到的散斑底片将包含宽广的空间频谱范围,且全场分析条纹清晰、灵敏度高、量程调节范围大。此方法不仅适用于各种材料的直接散斑法测量,具有经济、可靠、操作简便的特点,还能应用于平面及可展曲面构件的现场量测。  相似文献   
108.
In this article, we investigate the dependence of nuclear temperature on emitting source neutron-proton (\begin{document}$ N/Z $\end{document}) asymmetry with light charged particles (LCPs) and intermediate mass fragments (IMFs) generated from intermediate-velocity sources in thirteen reaction systems with different \begin{document}$ N/Z $\end{document} asymmetries, \begin{document}$ ^{64} \rm{Zn} $\end{document} on \begin{document}$ ^{112} \rm{Sn} $\end{document}, and \begin{document}$ ^{70} \rm{Zn} $\end{document}, \begin{document}$ ^{64} \rm{Ni} $\end{document} on \begin{document}$ ^{112,124} \rm{Sn} $\end{document}, \begin{document}$ ^{58,64} \rm{Ni} $\end{document}, \begin{document}$ ^{197} \rm{Au} $\end{document}, and \begin{document}$ ^{232} \rm{Th} $\end{document} at 40 MeV/nucleon. The apparent temperature values of LCPs and IMFs from different systems are deduced from the measured yields using two helium-related and eight carbon-related double isotope ratio thermometers, respectively. Then, the sequential decay effect on the experimental apparent temperature deduction with the double isotope ratio thermometers is quantitatively corrected explicitly with the aid of the quantum statistical model. The present treatment is an improvement compared to our previous studies in which an indirect method was adopted to qualitatively consider the sequential decay effect. A negligible \begin{document}$ N/Z $\end{document} asymmetry dependence of the real temperature after the correction is quantitatively addressed in heavy-ion reactions at the present intermediate energy, where a change of 0.1 units in source \begin{document}$ N/Z $\end{document} 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.
Positive solutions and eigenvalue intervals for nonlinear systems   总被引:1,自引:0,他引:1  
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   
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