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用脉冲激光饱和荧光法测定铀原子光吸收截面
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作者 李自卫 王新 +3 位作者 潘文杰 于贵明 弗林 张佳立 《激光杂志》 CAS CSCD 北大核心 1997年第4期34-36,47,共4页
本文介绍了用脉冲激光饱和荧光法,来测定铀的0~16900cm-1能级的吸收截面,讲述了测量光吸收截面的基本原理,实验测量过程,并用此方法测量铀原子光吸收截面和国外文献发表相吻合。
关键词 脉冲激光 吸收截面 荧光探测 光吸收截面
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用于真空紫外光吸收和光电离截面测量的多电极光电离室装置
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作者 刘付轶 齐飞 +2 位作者 盛六四 俞书勤 张允武 《原子与分子物理学报》 CAS CSCD 北大核心 1998年第2期253-260,共8页
详细介绍了所制的多电极真空紫外光电离室实验装置。它主要由光学聚焦系统、真空系统、多级光电离吸收室和数据采集系统四部分组成。其主要特点是使用圆筒形多级电极收集光电离产生的电子和离子,并能精确地测量分子的绝对光吸收、光电... 详细介绍了所制的多电极真空紫外光电离室实验装置。它主要由光学聚焦系统、真空系统、多级光电离吸收室和数据采集系统四部分组成。其主要特点是使用圆筒形多级电极收集光电离产生的电子和离子,并能精确地测量分子的绝对光吸收、光电离和光离解截面,以及光电离量子产率和光学振子强度分布等。结合光电离质谱技术,可获得碎片离子的部分光电离截面。最后给出初步实验结果。 展开更多
关键词 光电离室 紫外 光吸收截面 光电离截面 分子
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原子分子真空紫外光吸收和光电离绝对截面的精确测量 被引量:1
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作者 刘付轶 盛六四 +1 位作者 俞书勤 张允武 《光学学报》 EI CAS CSCD 北大核心 1998年第12期1601-1605,共5页
介绍了一种精确测量原子分子真空紫外光吸收和光电离绝对截面的实验方法。该方法的主要特点是使用圆筒形多级电极,有效地收集光电离产生的电子和离子,并利用高通量的同步辐射作光源,精确地测量分子(原子)的绝对光吸收、光电离和光... 介绍了一种精确测量原子分子真空紫外光吸收和光电离绝对截面的实验方法。该方法的主要特点是使用圆筒形多级电极,有效地收集光电离产生的电子和离子,并利用高通量的同步辐射作光源,精确地测量分子(原子)的绝对光吸收、光电离和光离解截面,以及光电离量子产率和光学振子强度分布等。利用该方法获得了Xe原子和N2分子的一些实验结果。 展开更多
关键词 光电离室 真空紫外 光吸收截面 光电离截面
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球形金属簇等离子体线宽的研究方法进展
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作者 朱俊 《陕西科技大学学报(自然科学版)》 2012年第1期116-121,共6页
由于量子尺寸效应,金属纳米粒子表现出一些特殊的光学性质,而金属纳米粒子在生物、化学和新型材料等方面的广阔应用前景,使我们对其光学性质的理解和研究变得至关重要.对于中间大小(半径R:0.5~2.5nm)的金属纳米粒子,Landau衰减是其主... 由于量子尺寸效应,金属纳米粒子表现出一些特殊的光学性质,而金属纳米粒子在生物、化学和新型材料等方面的广阔应用前景,使我们对其光学性质的理解和研究变得至关重要.对于中间大小(半径R:0.5~2.5nm)的金属纳米粒子,Landau衰减是其主要的能量耗散方式.作者系统总结了球形金属纳米粒子表面等离子体共振线宽的研究方法,介绍了粒子大小、温度和电介质环境对线宽的影响,并指出了近年来金属纳米粒子光学性质方面的研究热点. 展开更多
关键词 金属纳米粒子 表面等离子体 朗道衰减 光吸收截面 线宽
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Theoretical Studies on One-photon and Two-photon Absorption Properties of Pyrene-core Derivatives
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作者 丁明翠 张珍 +1 位作者 宋阳 王传奎 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第6期664-668,745,共6页
The analytic response theory at density functional theory level is applied to investigate onephoton and two-photon absorption properties of a series of recently synthesized pyrene-core derivatives. The theoretical res... The analytic response theory at density functional theory level is applied to investigate onephoton and two-photon absorption properties of a series of recently synthesized pyrene-core derivatives. The theoretical results show that there are a few charge-transfer states for each compound in the lower energy region. The one-photon absorption properties of the five investigated compounds are highly consistent with those given by experimental measurements. The two-photon absorption intensities of the compounds are greatly enhanced with the increments of the molecular sizes, in which the two-photon absorption cross section of the four-branched compound is about 5.6 times of that of the mono-branched molecule. Fhrthermore, it is shown that the two-photon absorption properties are sensitive to the geometrical arrangements. 展开更多
关键词 Two-photon absorption Response theory Pyrene-core derivative
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Influence of Integral Instability of Kramers-Kronig Transformation on Photoabsorption Cross Sections 被引量:1
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作者 MA Xiao-Guang GONG Yu-Bing QU Zhao-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第8期369-376,共8页
The photoabsorption cross sections of condensed atoms and molecules have proven to be dependent not only on the imaginary parts but also on the real parts of the polarizabilities due to the strong interatomie interact... The photoabsorption cross sections of condensed atoms and molecules have proven to be dependent not only on the imaginary parts but also on the real parts of the polarizabilities due to the strong interatomie interactions in condensed environment. The real parts of the polarizabilities calculated usually by using the famous Kramers-Kronig transformation (KKT) from the photoabsorption cross sections of the isolated atoms are very sensitive to the accuracy of the implementation method of the infinite integral in the KKT. The influence of the integral instability of the KKT and the real part of the polarizability on the variation of the photoabsorption cross sections with the number density and the structure of the condensed matter has been studied in the present work for the first time. The conclusion is that the integration method with interpolation has given more reasonable results than the direct truncation method if some appropriate interpolation functions have been used. Some notes and conclusions have also been given for the applications of the alternative coupled expressions of photoabsorption cross sections. 展开更多
关键词 condensed-phase photoabsorption Kramers-Kronig transformation dynamic polarizability
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Cavity Ring-Down Spectroscopy Measurements of Trace H_(2)S in SF_(6) and SF_(6)/N_(2) Mixture 被引量:1
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作者 ZOU Keyuan ZHU Min ZHANG Chaohai 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2022年第S01期113-119,共7页
H_(2)S is one of the most important characteristic decomposition components of SF_(6)insulated gas,and the detection of trace H_(2)S is significant for early fault diagnosis of gas insulated electrical equipment.A 157... H_(2)S is one of the most important characteristic decomposition components of SF_(6)insulated gas,and the detection of trace H_(2)S is significant for early fault diagnosis of gas insulated electrical equipment.A 1578 nm wavelength distributed feedback diode laser(DFB-DL)based cavity ring-down spectroscopy(CRDS)experimental platform is developed to monitor the concentrations of H_(2)S in SF_(6)and SF_(6)/N_(2)mixture carrier gas.The detection sensitivity is higher than 1×10^(-6).The absorption cross section parameterσis vital for calculating the concentration.With repeated experiments using standard gas samples,parameterσof H_(2)S in pure SF_(6)and SF_(6)/N_(2)mixture carrier with different mixing ratios is calibrated.Compared with the simulatedσvalues,the influence of carrier gas on the broadening of spectral profile is discussed.The variation of absorption cross sectionσwith different carrier gas mixing ratios is studied as well,so that the calculation of the concentration in the carrier gas of any mixing ratio is possible.Thus,the application of CRDS in trace component detection of gas insulated electrical equipment is promising. 展开更多
关键词 cavity ring-down spectroscopy(CRDS) absorption cross section H_(2)S SF_(6)decomposition component
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Effect of Substitution Site on Two-Photon Absorption and Excited States Properties of Lipid Droplets Detection NAPBr Dyes:a Theoretical Perspective
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作者 Hong-yang Wang Xiao-fei Wang +1 位作者 Jian-zhong Fan Yong Zhou 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第4期673-684,I0150,共13页
Two-photon fluorescence dyes have shown promising applications in biomedical imaging.However,the substitution site effect on geometric structures and photophysical properties of fluorescence dyes is rarely illustrated... Two-photon fluorescence dyes have shown promising applications in biomedical imaging.However,the substitution site effect on geometric structures and photophysical properties of fluorescence dyes is rarely illustrated in detail.In this work,a series of new lipid droplets detection dyes are designed and studied,molecular optical properties and non-radiative transitions are analyzed.The intramolecular weak interaction and electron-hole analysis reveal its inner mechanisms.All dyes are proven to possess excellent photophysical properties with high fluorescence quantum efficiency and large stokes shift as well as remarkable two-photon absorption cross section.Our work reasonably elucidates the experimental measurements and the effects of substitution site on two-photon absorption and excited states properties of lipid droplets detection NAPBr dyes are highlighted,which could provide a theoretical perspective for designing efficient organic dyes for lipid droplets detection in biology and medicine fields. 展开更多
关键词 Substituting effect Two-photon absorption cross section Non-radiative transition Fluorescence quantum efficiency
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Linear and Nonlinear Optical Properties of Novel Multi-branched Oligomers
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作者 Li-jing Gong Ying-hui Wang +3 位作者 Zhi-hui Kang Tian-hao Huang Ran Lu Han-zhuang Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第6期636-641,I0003,共7页
We investigate the fluorene-vinylene unit dependent photo-physical properties of multi- branched truxene based oligomers (Tr-OFVn, n=1-4) employing steady-state absorption and emission spectroscopy, transient absorp... We investigate the fluorene-vinylene unit dependent photo-physical properties of multi- branched truxene based oligomers (Tr-OFVn, n=1-4) employing steady-state absorption and emission spectroscopy, transient absorption spectroscopy, two-photon fluorescence, and z-scan technique. The results show that the increasing of fluorene-vinylene unit leads to a red-shift in the spectra of absorption and fluorescence, and shortens the excited state lifetime. Meanwhile, two-photon fluorescence efficiency and two-photon absorption cross section of truxene based oligolners gradually enhance in company with the extension of π- conjugated length. In addition, the values of two-photon absorption cross section modeled on the sum-over-state approach agree well with the experimental ones. The results indicate multi-branched truxene based oligomers bearing organic materials for two-photon applications. 展开更多
关键词 Multi-branch oligomer Two-photo absorption Z-SCAN
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Variation of Two-photon Absorption Cross Sections and Optical Limiting of Compounds Induced by Static Electric Field
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作者 Yu-jin Zhang Yu-zhi Song Chuan-kui Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第3期259-264,共6页
By numerically solving the Maxwell-Bloch equations using an iterative predictor-corrector finite-difference time-domain technique, we investigate propagating properties of a few-cycle laser pulse in a 4,4'-bis(di-n-... By numerically solving the Maxwell-Bloch equations using an iterative predictor-corrector finite-difference time-domain technique, we investigate propagating properties of a few-cycle laser pulse in a 4,4'-bis(di-n-butylamino) stilbene (BDBAS) molecular medium when a static electric field exists. Dynamical two-photon absorption (TPA) cross sections are obtained and optical limiting (OL) behavior is displayed. The results show that when the static electric field intensity increases, the dynamical TPA cross section is enhanced and the OL behavior is improved. Moreover, both even- and odd-order harmonic spectral components are generated with existence of the static electric field because it breaks the inversion symmetry of the BDBAS molecule. This work provides a method to modulate the nonlinear optical properties of the BDBAS compounds. 展开更多
关键词 Static electric field Optical limiting Two-photon absorption Organic molecule
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Theoretical Analysis on Optical Limiting Properties of Newly Synthesized Graphene Oxide-Porphyrin Composites
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作者 Yu-jin Zhang Wen-jing Yang +2 位作者 Jian-zhong Fan Yu-zhi Song Chuan-kui Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第3期257-262,I0001,共7页
Optical limiting (OL) properties and two-photon absorption (TPA) of a series of covalently linked graphene oxide-porphyrin composite materials have been investigated by numerically solving the rate equations and f... Optical limiting (OL) properties and two-photon absorption (TPA) of a series of covalently linked graphene oxide-porphyrin composite materials have been investigated by numerically solving the rate equations and field intensity equation with an iterative predictor-corrector finite-difference time-domain technique in nanosecond time domain. Our results show that graphene oxide-porphyrin composites exhibit enhanced OL behavior and possess larger TPA cross section compared with individual porphyrins. Interestingly~ unlike the previous result that porphyrin with heavier central metal shows better nonlinear abilities than that with- out metal substitute, graphene oxide-metal free porphyrin composite has stronger nonlinear absorption properties compared with graphene oxide-metal porphyrin composite. The com- putational results are in reasonable agreement with the experimental ones. Special attention has been paid to the influence of thickness of the medium and pulse width on TPA cross sections, which presents that larger TPA cross sections are obtained as the medium is thicker or the pulse duration is wider. 展开更多
关键词 Optical limiting Two-photon absorption Graphene oxide PORPHYRIN
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Analytical Absorption Cross-Section for Photon by a Hydrogen 2s Atom
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作者 Boniface Otieno Ndinya Stephen Onyango Okeyo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第4期659-661,共3页
We calculate the absorption cross-section for photon by a hydrogen 2s atom using the quantum-classical approximation for the total photo cross-section of many electron atoms. With the application of the first-order te... We calculate the absorption cross-section for photon by a hydrogen 2s atom using the quantum-classical approximation for the total photo cross-section of many electron atoms. With the application of the first-order term of the Baker Hausdorf expansion, the absorption cross-section for the hydrogen 2s atom decreases to a minimum, the Cooper paJr minimum, at low photon energy. Such a minimum is absent in the exact absorption cross-section for photon by a hydrogen 2s atom. We have extended the calculation for the absorption cross-section of the hydrogen 2s atom using the quantum-classical approximation for the total photo cross-section of many electron to include the second-order term of the Baker-Hausdorf expansion and observed a great reduction in the dip associated with the Cooper pair minimum at the zero crossing. 展开更多
关键词 absorption cross-section Cooper pair minimum and Baker-Hausdorf expansion
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激光诱导荧光法测量钆原子光谱 被引量:1
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作者 王德武 王建华 王立军 《清华大学学报(自然科学版)》 EI CAS CSCD 北大核心 2002年第S1期23-25,共3页
为了有效地利用同位素研究钆原子的光谱特性。采用原子蒸气束激光诱导荧光法测量钆原子的第一激发态的同位素位移及超精细结构、原子跃迁自发辐射的分支比和原子蒸气束的多普勒宽度。通过对测量结果的分析和计算 ,分别给出钆原子 5条谱... 为了有效地利用同位素研究钆原子的光谱特性。采用原子蒸气束激光诱导荧光法测量钆原子的第一激发态的同位素位移及超精细结构、原子跃迁自发辐射的分支比和原子蒸气束的多普勒宽度。通过对测量结果的分析和计算 ,分别给出钆原子 5条谱线的同位素位移和超精细结构、两个能级 (17795 .2 6 7cm- 1 ,172 2 7.96 9cm- 1 )的寿命 (2 37ns,94 7ns)和光吸收截面 (1.39× 10 - 1 3cm2和 8.77×10 - 1 4cm2 )。这些研究结果为进一步测量钆原子高激发态和电离态的光谱打下基础。 展开更多
关键词 同位素位移 超精细结构 能级寿命 光吸收截面 原子蒸气束
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共振Q^2相关的极化结构函数性质的研究 被引量:1
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作者 董宇兵 《高能物理与核物理》 CSCD 北大核心 1998年第6期550-555,共6页
在组分夸克模型基础上,极化质子、中子结构函数随Q~2演化关系得到了研究.同时理论对总的光吸收截面也给出了相应的预言.计算结果与实验数据相一致.
关键词 共振态 极化结构函数 Q^2演化关系 光吸收截面
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HMX分子异构体性质的理论研究
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作者 孙娜娜 洪许海 +1 位作者 焦亚龙 王锋 《中国科学:物理学、力学、天文学》 CSCD 北大核心 2013年第6期749-755,共7页
在含时密度泛函理论的框架下,首先选取了三个软件包(PWSCF软件包、CPMD软件包、OCTOPUS软件包)和两种泛函(PBE泛函、LDA泛函)构成的五种方案优化了HMX单分子异构体的四种构型(Boat构型与Boat-Boat构型属于C2群,Chair构型属于Ci群,Boat-C... 在含时密度泛函理论的框架下,首先选取了三个软件包(PWSCF软件包、CPMD软件包、OCTOPUS软件包)和两种泛函(PBE泛函、LDA泛函)构成的五种方案优化了HMX单分子异构体的四种构型(Boat构型与Boat-Boat构型属于C2群,Chair构型属于Ci群,Boat-Chair构型属于C1群),并计算了各构型的相对总能量关系,所得结论与前人有所不同,Boat-Boat构型总能量不是最低;其次计算了HMX单分子异构体的态密度,结果表明除Boat-Chair型外其他构型均具有明显的能级分裂特征,各构型均具有绝缘体特征且Boat型能隙最大;最后计算了各构型的光吸收截面,发现Boat构型的HMX分子的光吸收截面中能观察到的显著的峰最多,其次是Boat-Boat构型、Boat-Chair构型,Chair构型最少. 展开更多
关键词 HMX分子 态密度 光吸收截面 含时密度泛函理论
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The orbital g-factor and related sum rules 被引量:2
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作者 BENTZ Wolfgang ARIMA Akito 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第2期194-197,共4页
The renormalization of the orbital g-factor in nuclei is discussed on the basis of gauge invariance.The relation of the orbital g-factor to the integrated E1 photoabsorption cross section is reviewed,and its relation ... The renormalization of the orbital g-factor in nuclei is discussed on the basis of gauge invariance.The relation of the orbital g-factor to the integrated E1 photoabsorption cross section is reviewed,and its relation to the M1 sum rule for the scissors mode of deformed nuclei is examined. 展开更多
关键词 nuclear magnetic moments G-FACTORS giant resonances sum rules
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The optical properties of Tm^(3+) doped Na_5Lu_9F_(32) single crystal
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作者 盛启国 夏海平 +3 位作者 汤庆阳 何仕楠 章践立 陈宝玖 《Optoelectronics Letters》 EI 2017年第3期201-205,共5页
Tm^(3+) doped Na_5Lu_9F_(32) single crystal with high optical quality was grown by an improved Bridgman method. The Judd-Ofelt intensity parameters ?_t(t=2, 4, 6) were calculated according to the measured absorption s... Tm^(3+) doped Na_5Lu_9F_(32) single crystal with high optical quality was grown by an improved Bridgman method. The Judd-Ofelt intensity parameters ?_t(t=2, 4, 6) were calculated according to the measured absorption spectra and physical-chemical properties of the obtained Na_5Lu_9F_(32) single crystal. The stimulated emission cross-section of the ~3F_4→~3H_6 transition(~1.8 μm) is 0.35×10^(-20) cm^2 for Tm^(3+) doped Na_5Lu_9F_(32) single crystal. The emission spectra under the excitation of 790 nm laser diode(LD) and fluorescence lifetime at 1.8 μm were measured to reveal the fluorescence properties of Tm^(3+) doped Na_5Lu_9F_(32) single crystal. The research results show that the Tm^(3+) doped Na_5Lu_9F_(32) single crystal has larger stimulated emission cross-section compared with other crystals. All these spectral properties suggest that this kind of Tm^(3+)doped Na_5Lu_9F_(32) crystal with high physical-chemical stability and high-efficiency emission at 1.8 μm may be used as potential laser materials for optical devices. 展开更多
关键词 Bridgman lifetime excitation stimulated relaxation excited transparency spacing spectrometer termine
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