Ground-state complex formation of perylene with pyromellitic dianhydride studied by static fluorescence quenching

The association of complex formation with static quenching in CT systems was investigated. Evaluation of the data made evident that the inner filter effect must be allowed for. Time-resolved and temperature-dependent stationary measurements of fluorescence led to the separation of dynamic and static quenching components. The static quenching constant is discussed with respect to the equilibrium constant of complex formation determined by absorption spectroscopy.     

Selective quenching of tryptophanyl fluorescence in bovine serum albumin by the iodide ion

Modified Stern-Volmer equation is obeyed by bovine serum albumin (BSA)-iodide system showing selective quenching of tryptophanyl fluorescence of BSA. The fraction of accessible protein fluorescence is 0.56 and the effective Stern-Volmer constant is 290 M^-1 at pH 7.4 in 0.005 M phosphate buffer at 25°C. Collisional quenching is operative both in the BSA -I⁻¹ system and the model system, tryptophan-I⁻¹. It is supported by the observed relationship between the ratio of quenching rate constants (k _q ) and diffusion coefficients and alsok _q with bulk viscosity.     

碱土金属氟卤化物中的Eu3+的荧光光谱特征

本文系统研究了MFX体系中Eu³⁺荧光光谱特征,着重讨论了X^-,M²⁺及杂质缺陷(主要为O^2-)对Eu³⁺发光的影响.     

用计算机测量PN结的反向物理特性

本对PN结反向物理特性，应用电子技术和计算机技术实现了对实验过程的控制和效据处理。     

电流并联负反馈放大器实验的研究

用实验的方法，研究电流并联负反馈对放大器性能的改善，提出电流型、并联型负反馈放大器性能参数的测量方法。     

离心泵在启动阶段的水力特性研究

针对工作的离心泵,分析了其内部流体的流动情况,建立了在非稳定工况下操作的理论扬程公式,非稳态理论扬程包括旋转加速附加扬程和水流加速消耗扬程以及由于流动速度变化引起泵壳中的附加压力而产生的扬程。在离心泵的启动阶段,对其在不同阀门开度下的水力性能进行了试验研究。测量了瞬时转速、流量、扬程随时间的变化关系,并把试验结果进行修正。由于启动时一部分扬程用来提供流体加速,压力传感器测量不到,因此必须把试验扬程加以修正。将理论计算与修正的试验结果进行了比较分析,两者基本吻合。     

PDT光敏剂HA在不同液相体系下的光谱特性研究

为了对候选光敏剂竹红菌甲素(HA)进行改性并保持其优异的敏化特性,对HA的光谱特性和激发态性质作了进一步的指认。系统研究了HA在不同液相体系下的吸收和荧光光谱,对指认HA的光谱和电子跃迁的机制提出了新的依据,结果表明,吸收带I产生于π-π*跃迁,吸收带Ⅱ和Ⅲ产生于P-π共轭所导致的L→aπ跃迁的电子振动结构;荧光发射带I和Ⅱ是产生于同一跃迁机制S1(L,aπ)→S0的正常荧光的振动结构。     

Application of x-ray fluorescence analysis to investigation of the composition of gunshot residues

We have used x-ray fluorescence analysis to study the elemental composition of gunshot residues from smooth-bore and rifled-bore guns. We have established that it is possible to differentiate between types of projectiles (jacketed/lead), types of primers (corrosive/noncorrosive), and types of propellant powders (black/smokeless) by analysis of the elemental composition of the gunshot residues. We have shown that the mercury content in gunshot residues on the surface of the object carrying the residues steadily decreases as storage time increases. Despite this fact, mercury can be preserved as a component of gunshot residues on the object (cotton cloth) under room conditions for more than 45 days. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 3, pp. 320–325, May–June, 2006.     

我国封闭式投资基金业绩评价实证研究

随着我国基金行业超常发展,恰当的分析和评价基金业绩已越来越重要。本文根据CAPM的基本原理,利用国外先进的基金业绩评价方法对我国封闭式基金的综合业绩进行实证研究。研究结果表明:总体来看,基金获得的市场超额收益显著为负。基金经理不具有证券选择能力,但具有一定的市场择时能力,但这两种能力均不显著。同时,我们还发现不同投资风格的基金经理具有不同的证券选择能力和市场择时能力。