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61.
Accurate calculation of the potential energy curve and spectroscopic parameters of X~2Σ~+ state of ~(12)Mg~1H 下载免费PDF全文
High level calculations on the ground state of12Mg1 H molecule have been performed using multi-reference configuration interaction(MRCI) method with the Davidson modification. The core–valence correlation and scalar relativistic corrections are included into the present calculations at the same time. The potential energy curve(PEC) of the ground state, all of the vibrational levels and spectroscopic parameters are fitted. The results show that the levels and spectroscopic parameters are in good agreement with the available experimental data. The analytical potential energy function(APEF) is also deduced from the calculated PEC using the Murrell–Sorbie(M–S) potential function. The present results can provide a helpful reference for the future spectroscopic experiments or dynamical calculations of the molecule. 相似文献
62.
Enhanced ionization of vibrational hot carbon disulfide molecules in strong femtosecond laser fields 下载免费PDF全文
By using a heated molecular beam in combination with a time-of-flight mass spectrometer, we experimentally study the ionization of vibrational-hot carbon disulfide(CS_2) molecules irradiated by a linearly polarized 800-nm 50-fs strong laser field. The ion yields are measured in a laser intensity range of 7.0 × 10~(12) W/cm~2–1.5 × 10~(14) W/cm~2 at different molecular temperatures of up to 1400 K. Enhanced ionization yield is observed for vibrationally excited CS_2 molecules.The results show that the enhancement decreases as the laser intensity increases, and exhibits non-monotonical dependence on the molecular temperature. According to the calculated potential energy curves of the neutral and ionic electronic states of CS_2, as well as the theoretical models of molecular strong-field ionization available in the literature, we discuss the mechanism of the enhanced ionization of vibrational-hot molecules. It is indicated that the enhanced ionization could be attributed to both the reduced ionization potential with vibrational excitation and the Frank–Condon factors between the neutral and ionic electronic states. Our study paves the way to understanding the effect of nuclear motion on the strongfield ionization of molecules, which would give a further insight into theoretical and experimental investigations on the interaction of polyatomic molecules with strong laser fields. 相似文献
63.
以K3Mn(CN) 6,N ,N 二甲基甲酰胺和Eu(NO3) 3·6H2 O为原料合成了新型一维链状氰根桥联配合物[Eu(DMF) 4(H2 O) 2 Mn(CN) 6·H2 O]n,并通过元素分析、红外光谱和紫外光谱进行了表征 .利用单晶X射线四圆衍射测定了配合物的晶体结构 ,结果表明 ,晶体属单斜晶系 ,P2 1/c空间群 ,晶胞参数a =1.2 992 (3)nm ,b =1.2 76 4(3)nm ,c =1.915 4(4 )nm ,β =10 9.42 (3)°,V =2 .995 6 (12 )nm3,Dx=1.5 73Mg/m3,Z =4,R =0 .0 372 ,Rw=0 .0 96 2 ,GOF =1.0 95 .在Eu和Mn原子之间存在两个CN桥 ,配合物呈现一维链状结构 . 相似文献
64.
boldmath B3Σu-–X3Σg- transition in selenium dimer: ab initio multireference configuration interaction calculations 下载免费PDF全文
Theoretical investigation of low-lying electronic states and B3Σu-–X3Σg- transition properties of selenium dimer using size-extensivity singly and doubly excitation multireference configuration interaction theory with nonrelativistic all-electron basis set and relativistic effective core potential plus its split valence basis set is presented in this paper. The spectroscopic constants of ten low-lying Λ-S bound states have been obtained and compared with experiments. Spin-orbit calculations for coupling between B3Σu- sates and repulsive 1Πu, 5Πu states have been made to interpret the predissociation mechanisms of the B3Σu- state. The lifetimes of B3Σu- (v=0~6) have been calculated with scalar relativistic effects included or excluded, respectively, and reasonably agree with experimental values. 相似文献
65.
针对近年来基于有机改性硅氧烷作为连接体构筑的光功能稀土杂化材料的最新进展进行了评述,其重点着眼于稀土离子的优良光敏化有机配体修饰硅氧烷偶联剂获得有机改性硅氧烷,以其作为多功能连接体(分子桥)来实现对发光稀土杂化材料体系的化学键组装。内容主要涉及基于芳香羧酸衍生物类改性硅氧烷构筑稀土杂化材料、基于β-二酮及类β-二酮衍生物类改性硅氧烷构筑稀土杂化材料、基于大环配体衍生物类改性硅氧烷构筑稀土杂化材料、基于杂环等衍生物类改性硅氧烷构筑稀土杂化材料、基于有机改性硅氧烷多元组装稀土杂化材料及基于离子液体改性硅氧烷构筑稀土介孔硅杂化材料几个重要方面。主要结合我们自己的近期研究工作,通过系统总结来展现该领域的研究面貌并提出未来展望。 相似文献
66.
67.
采用从头计算方法从理论上解释了实验中双原子分子S2(B3∑u-→X3∑g-)吸收谱中谱带(18,0)开始出现的弥散现象.计算了包含自旋-轨道耦合(SOC)的B3∑u-和排斥的15∏u,23∑u+态的电子势能曲线.对于(18,0)谱带开始弥散,给出了与其他文献不同的物理解释.计算结果表明B3∑u-与15∏u,23∑u+态的SOC作用导致预解离对谱带的弥散起着决定作用,并与实验结果作了比较,符合很好. 相似文献
68.
将C60掺入聚甲基丙烯酸甲酯形成C60复合材料。研究了其折射率与温度变化的关系;随加入C60量不同,导致折射率有不同的变化;并研究了该复合物经紫外线照射后的折射率变化。结果表明:掺入C60的聚甲基丙烯酸甲酯折射率比纯甲基丙烯酸甲酯折射率明显提高。此种C60复合物的折射率随温度升高而降低,而且C60含量越高,折射率对温度变化越敏感;经紫外线照射后的C60复合物的折射率对温度的变化更加敏感。 相似文献
69.
将杯[4]醌(Calix[4]quinone,C4Q)通过灌注法与有序介孔炭CMK-3制备成纳米复合材料,可抑制其在常规有机电解液中的溶解。 为了进一步提升其电化学性能,本文在C4Q/CMK-3复合材料中加入单壁碳纳米管(SWCNTs),减少了CMK-3的用量,并代替导电炭黑Super-P作为导电剂,通过脱泡搅拌法制备了C4Q/CMK-3/SWCNTs复合材料。 研究表明,当m(C4Q):m(CMK-3):m(SWCNTs)为1:1:1时,电化学性能最佳,0.1 C电流密度下循环100圈后,电池的容量保持为238.7 mA·h/g,当电流密度增大到1 C时,放电容量仍有260 mA·h/g,这是由于SWCNTs在复合材料C4Q/CMK-3中构建了三维导电网络,增强了电极的稳定性,降低了电池内阻,从而提升了电池的循环性能与倍率性能。 相似文献
70.
Spin--orbit ab initio curves of 80Se2+ ion and theassignment of photoelectron spectra of 80Se2 molecule 下载免费PDF全文
This paper carries out ab initio calculations to study the ^80Se2(X^3Σg^-) state and ^80Se2^+(X^2Πg), ^80Se2^+(a^4Πg) states by using completed active space self-consistent field and multi-reference second order perturbation theory. The electronic curves of these states including spin-orbit coupling are calculated, and then the spectroscopic parameters are obtained. The photoelectron spectra of ^80Se2 molecule in gas phase are assigned according to Franck-Condon analysis based on calculated potential energy curves. The ionization energies of ^80Se2 molecule are determined by the present calculation. 相似文献