一个新的具有双光子诱导荧光测量能力的在水中对铅离子有选择性的荧光探针

报道了一个对Pb^2＋具有很好选择性的探针1,其荧光团部分为：1,4-二氰基-2,5-联（苯乙烯基）苯;配体为：[（2-羧基甲氧基-苯基）-羧基甲基-胺基]-乙酸．在探针1的水溶液中滴加铅离子,它的荧光发射光谱发生变化,在590nm处出现一个新的宽带峰．探针1在生理环境的pH范围内不受pH的影响,并且在740nm,它的双光子吸收截面为最大：51GM．     

Absorption Cross Section and Decay Rate of Stationary Axisymmetric Einstein-Maxwell Dilaton Axion Black Hole

The low energy absorption cross section and the decay rate of the stationary Axisymmetric Einstein-Maxwell Dilaton Axion black hole for massless scalar particles is calculated analytically. It is shown that the partial absorption cross section increases as the rotating parameter a and the absolute value of the dilaton D decreases. It is also shown that the partial absorption cross section is not always positive due to superradianee factor ω - mΩ. However, the decay rate of this black hole is always positive.     

二氧化钒纳米点阵红外光学特性研究

针对二氧化钒纳米点阵从半导体到金属的可逆相变,考虑到点阵中各个点之间散射光的交互作用,基于VO2在不同温度和波长下的折射率和消光系数,以及小颗粒的吸收和散射特性,建立了VO2纳米颗粒的数学模型,研究了VO2纳米颗粒的相变光学特性.结果表明,随着波长变化,吸收截面相对散射截面占主导,金属相在980nm附近出现吸收峰值;随着温度变化,可见光区域的消光系数变化较小,而红外区域较大,其中在近红外区域的消光系数变化最大.在纳米点阵中,消光截面随着颗粒间距变化,当颗粒间距增大时,消光峰值出现红移,且峰值大小也会随之增大;当间距超过一定数值后,峰值反而会逐渐减小.采用多孔氧化铝掩模的方法,通过磁控反应溅射制备VO2纳米点阵,测试结果表明其透过率比薄膜的透过率高.     

有机材料的双光子吸收物理特性及其应用

近年来，具有大双光子吸收截面的有机材料的物理性质及其应用的研究成为令人关注的重要研究课题。文章综述了有机材料的双光子吸收过程，物理特性以及其实验测试和研究方法，评述了有机材料的双光子吸收效应的应用，包括上转换散射，光学限幅，双光子荧光显微成像、三维光信息存储和光学微加工等。     

Variation of Two-photon Absorption Cross Sections and Optical Limiting of Compounds Induced by Static Electric Field

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.     

掺铒光纤放大器增益的温度依赖关系

报道掺铒光纤放大器增益随温度变化的依赖关系，提出了一个解释这种依赖关系的数学模型。此模型基于如下假设：由于温度的变化，引起处在基态和激发态的斯塔克能级上的掺铒离子浓度的重新分布，从而引发光纤发射截面和吸收截面的变化。理论结果与实验结果符合很好。     

小分子光解动力学的理论研究

光解过程是化学中的核心问题之一。量子态分辨的光解动力学可以使人们在原子与分子的层次上深刻理解光解反应的机制。态-态水平的光解动力学在过去四十年中取得了长足的进步,实验和理论的相互结合极大地促进了我们对光解反应本质的认识。本文综述了小分子态-态光解动力学的理论研究进展,总结了H2O和CH3I这两个最具代表性体系的态-态光解动力学研究成果,并提出了该领域未来面临的挑战。     

车载二氧化硫差分吸收激光雷达系统

研制了一套探测低层大气二氧化硫的车载可移动激光雷达系统.该系统选用的差分波长对为300.05nm和301.50nm.光源采用两台Nd…YAG激光器分别泵浦两台窄线宽染料激光器经过倍频来获得.激光经过合束、扩束后与望远镜同轴发射.后向散射信号被近牛顿式望远镜接收后,通过光电倍增管转换为电信号,然后被数据采集卡采集,最后用来反演二氧化硫分布廓线.在淮南地区进行了针对近地面水平探测的外场实验,结果表明,在0.8~3.0km范围内,当晚二氧化硫浓度在20μg·m-3上下波动,气象部门地面仪器结果为18~22μg·m-3,实验结果与仪器结果具有可比性.     

Growth and Spectroscopic Properties of Nd3＋：Sr3Gd2（BO3）4 Crystal

<正>This paper reports the growth,X-ray diffraction and spectroscopy of Nd~(3+):Sr_3Gd_2(BO_3)_4 crystal.A Nd~(3+):Sr_3Gd_2(BO_3)_4 crystal with dimensions ofφ20×45 mm~3 has been grown by the Czochralski method.Nd~(3+):Sr_3Gd_2(BO_3)_4 crystal belongs to the orthorhombic system,space group Pnma(D_(2h))with a=0.7401,b=1.604 and c=0.8755 nm.The absorption and emission spectra of Nd~(3+):Sr_3Gd_2(BO_3)_4 were investigated.The absorption cross sectionσ_a is 3.11×10~(-20)cm~2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm.The luminescence lifetimeτ_f is 51.7 us.The emission cross sectionσ_e at 1064 nm wavelength is 1.09×10~(-19)cm~2.     

xF （or y）-Dependence of Nuclear Absorption and Energy Loss Effects on J/ψ Production

By means of the nuclear parton distribution studied only with lepton deep-inelastic scattering experimental data, the J/ψ ＂normal nuclear absorption＂ and energy loss effects are studied in a GIauber formalism at HERA and RHIC energies. Assuming that the absorption cross section σabs increases with the charmonium-nucleon center of mass energy, the results reveal a significant dependence of the aabs on rapidity g at RHIC energies. The initial-state energy loss effect, which is found important only at HERA energies, is also considered, and its influence should be eliminated when we studied the absorption effect at low collision energies. Finally, we also present the theoretical prediction for LHC.