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排序方式: 共有107条查询结果,搜索用时 62 毫秒
1.
飞秒泵浦—探测实验数据分析   总被引:4,自引:0,他引:4  
陈述了几种获取飞秒泵浦 探测实验数据中的光解动力学信息的解析物理模型 .其中单分量和双分量模型用来解释母体分子的单通道和双通道解离过程 ,另一个单分量模型用来解释碎片分子的解离或去激发过程 .所有模型都结合泵浦 探测实验数据予以解释  相似文献
2.
XeF2光解离波时空特性研究   总被引:4,自引:2,他引:2  
利用分幅相机拍摄了不同实验条件下的XeF2光解离波图像,反映了解离波的形成过程,获得了不同XeF2初始浓度下光解离波半径、解离层厚度、发展速度随时间的变化曲线,分析了光解离波参数的时间、空间特性.结果表明,光解离波在目前实验条件下所达到的最大距离约3 cm,解离波发展速度最大达28km/s;XeF2初始浓度越低解离波半径越大,发展速度越快,解离层厚度越厚.  相似文献
3.
焦耳量级光抽运XeF蓝绿激光器   总被引:4,自引:0,他引:4  
阐述了焦耳量级XeF(C-A)激光器的总体设计及抽运源辐射能力的测试方法,分析了XeF(C-A)激光特性参量与XeF2初始浓度、输出透过率以及气体成分之间的关系。抽运源采用紧凑型结构,有效地减小了放电回路面积,使回路电感降低到330nH,从而使放电沉积效率达到74%,抽运源平均沉积功率密度达到12MW/cm。利用分幅相机拍摄了XeF2光解离波并对抽运源辐射能力进行了诊断,抽运源辐射在140~170nm波段的光子出射通量达到5×1023s-1.cm-2,辐射亮度温度高于25kK。激光器有效激活长度80cm,采用平凹谐振腔,激光器获得了稳定的焦耳级能量输出,最大输出能量2.5J,总转换效率0.1%,激光脉宽约为700ns。  相似文献
4.
激发态CsHe(Ar)分子的光离解   总被引:3,自引:1,他引:2       下载免费PDF全文
研究Cs(62P)+He(Ar)+nhν→Cs(92D)+He(Ar)+(n-1)hν过程,激光频率调到Cs9D3/2→6P1/2跃迁谱线的蓝翼20~100cm-1,测量了精细结构谱线强度分支比I(9D3/2→6P3/2)/I(9D5/2→6P3/2)。实验表明,原子相互作用势和非绝热效应在离解动力学中起关键作用。  相似文献
5.
双向光泵浦XeF(C-A)激光   总被引:3,自引:2,他引:1  
讨论了双向光泵浦XeF(C—A)激光技术,给出了双向泵浦情况下的XeF2光解离波图像。在双向泵浦条件下XeF(C-A)激光输出能量提高了近3倍,最大输出达到3.3J,激光脉宽增加到1100ns。激光输出特性受XeF2初始浓度的显著影响,激光形成时间随XeF2初始浓度增大而加长,激光脉宽先增大后减小,激光近场光斑呈现出不同的形状,由方形变化为“X”形状。  相似文献
6.
若丹明6G光解过程的顺磁共振研究   总被引:1,自引:1,他引:0  
本文报道了用顺磁共振研究激光染料若丹明6G的光解过程。实验表明染料三重态分子和溶剂分子间存在着能量转移。  相似文献
7.
Photodissociation of NaH using time-dependent fourier grid method   总被引:1,自引:0,他引:1  
We have solved the time dependent Schr?dinger equation by using the Chebyshev polynomial scheme and Fourier grid Hamiltonian method to calculate the dissociation cross section of NaH molecule by 1-photon absorption from the X 1Σ+ state to the B 1Π state. We have found that the results differ significantly from an earlier calculation [1] although we have used the same set of potential energy curves [2].  相似文献
8.
    
The fluorescence spectra of CS2 and SO2 have been studied at three incident photon wavelengths of 121.6, 73.6–74.4 and 58.4 nm and relative production cross sections for different product states have been measured. The CS(A 1Π→X 1Σ+) system between 240 and 290nm has been obtained when CS2 is photoexcited at 121.6nm whereas CS 2 + (B 2Σ u +X 2Π g ) and CS 2 + (A 2Π u X 2Π g ) systems have been produced between 276 and 295 and 437 and 555nm respectively when excited by both the incident photon wavelengths of 73.6–74.4 and 58.4nm. The fluorescence spectra of SO2 obtained at 121.6 and 73.6–74.4nm include the vibrational bands of SO(A 3Π→X 3Σ) and SO(B 2ΠX 3Σ) systems from 240 to 268 and 268 to 442nm respectively whereas the emission spectrum at 58.4nm, has contributions from the two SO systems and SO+(A 2Π→X 2Π) system. In all these emission spectra, the fluorescence bands of different systems have been analyzed and their relative production cross sections have been measured. The results obtained in the present investigations have been compared with a few recent reliable measurements reported in literature.  相似文献
9.
Summary Photon emitted in the visible and near ultraviolet range by germinating soya seeds has been measured by means of a low-noise photomultiplier coupled to a data acquisition system. The photon energy spectrum, determined by means of a set of optical filters, shows two main contributions in the red and UV bands. Results show that both the radiation intensity and its spectrum change during germination according to seed physiological conditions. The photon emission of seeds at rest changes with their germinability. The UV component at the germination beginning is a factor 6 larger for living seeds than for the devitalized ones. This result can be interpreted as an experimental evidence of the existence of mitogenetic radiation. The authors of this paper have agreed to not receive the proofs for correction.  相似文献
10.
    
S M Ahmed  Vijay Kumar 《Pramana》1992,39(4):367-380
The photoabsorption and fluorescence cross-sections for carbon disulphide have been measured in the 188.2–213 and 287.5–339.5 nm spectral regions using an argon mini-arc light source. The absorption cross-sections have been measured with an accuracy of ±4.2% whereas the most probable error estimated in the case of fluorescence cross-sections is ±5.1%. The fluorescence quantum yields for CS2 have also been obtained in the two spectral regions.  相似文献
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