散射背景下激光热透镜光谱分析法测定人体血清中锌量

建立了散射背景下测定人体血清中Zn^2＋含量的激光热透镜光谱分析方法。比较了蛋白质微粒散射对于分光光度法和激光热透镜光谱分析法测定的影响。结果表明，激光热透镜光谱分析方法能够避免溶液中存留蛋白质微粒散射的影响。Zn^2＋量在0～1．6μg/mL范围内呈线性关系（r=0．9986），检出限为1ng/mL。应用于人体血清中Zn^2＋含量的测定，与原子吸收法测定结果基本一致。     

毛细管微池激光热透镜光谱分析方法研究

采用毛细管为测定微池,研究了毛细管微池激光热透镜光谱分析方法。理论上给出了毛细管微池激光热透镜光谱分析表达式。探讨了毛细管微池光反射的影响及其在光路位置特征、有机溶剂增强效应等。应用毛细管微池激光热透镜光谱分析于钼蓝法测定磷和浊点萃取测定孔雀石绿。结果表明建立的毛细管微池激光热透镜光谱分析方法,具有简单易行、高灵敏度的特点,适用于微量样品的分析测定。该研究不仅对于微量样品的测定具有应用价值,而且对于激光热透镜光谱分析法在绿色分析化学中的应用具有积极的促进作用。     

交叉束激光热透镜光度法的研究

激光热透镜光度法是一种高灵敏度光谱分析技术。本文用探测束非聚焦的He-Ne激光双光束交叉热透镜技术研究了影响热透镜灵敏度的几个因素,并对远场光斑截面内信号强度分布进行了测定,对实验结果进行了讨论。在正交束构型的最佳参数下,检测了1-(2-吡啶偶氮)-2-萘酚(PAN)-Co(Ⅲ)的氯仿溶液,得到最小吸光度为1.17×10~(-6),相当于1.7 ng/mL的     

激光热透镜光谱分析法*

激光热透镜光谱法是20世纪80年代发展起来的一种光热光谱分析技术。该法以其高灵敏度、低检出限以及适应于微、少量样品分析等特点引 分析工作者的极大兴趣。本文从测量装置、理论、痕量无机物和有机物测定以及与其它分析技术的联用等方面对1990年以来激光热透镜光谱分析法的进展作了较为详细的综述。     

脉冲激光热透镜光度法的研究Ⅰ.钕的测定

本文采用探测激光非聚焦型光学结构,用自装的热透镜实验装置,研究了溶液中Nd~(3+)的热透镜行为和影响热透镜效应的一些因素。用热透镜光度法直接分析了混合轻稀土氧化物样品中钕的含量。大量共存的镧、铈、镨不干扰测定。用1.8mJ/脉冲的加热激光能量,检出限为3.2×10~(-5)吸光度。     

间接原子吸收法测定药物制剂中布洛芬的含量

鉴于布洛芬(简称BLF)在医药上的应用价值，其含量的测定一直为人们所关注。目前该药的测定方法有酸碱滴定法、色谱法、紫外分光光度法及差示扫描量热法等，而用原子吸收法测定，尚未见报道。本实验基于BLF在适当的酸性条件下与Cu^2 形成络合物，通过CHCl3萃取，测定水相中剩余Cu^2 的含量来利用络合反应-原子吸收分光光度法测定药物制剂中BLF的含量。用于实际样品的测定，获得满意结果。     

左旋18—甲基炔诺酮—硅橡胶缓释体系小角激光散射法研究

以小角激光前向散射和背散射法研究了左旋１８－甲基炔诺酮－甲基乙烯基硅橡胶缓释体系的光散射时效行为，用紫外分光光度法测定释放过程，讨论药物释放过程中高分子链段运动和聚合物结构对药物释放的影响．     

高分子聚合物对激光热透镜分析的增强作用

本文报道非水溶性高分子对激光热透镜在痕量金分析中的增强作用，结果表明，聚氯乙烯（ＰＶＣ）能改变体系的热物理特性，并使体系最大吸收波长蓝移，从而增强热透镜光谱（ＴＬＳ）的信号强度，该方法的分析灵敏度比分光光度法高三个数量级，成功地用于化探样品中痕量金的测定。     

催化近场激光热透镜光谱法测定痕量铱

将近场激光热透镜光谱分析法与动力学分析法相结合.基于铱(Ⅳ)催化高碘酸钾氧化耐尔蓝A的动力学反心,建立了催化近场激光热透镜光谱法测定痕量铱的新方法,并探讨了反应机理。结果表明:铱浓度在0.05～2.4μg/L范围内呈线性关系;俭出限为6.2 x 10-12g/mL。应用该方法测定矿样中痕量铱.结果满意。     

盐析剂——氯化钠存在下稀土含量的准确测定

分光光度法(Spectrophotometry)和电感耦合等离子体发射光谱法(ICP-AES)是常用的测定单一稀土含量的方法。但是萃取稀土过程中通常会加入盐析剂NaCl,萃余水相中大量钠离子所产生的光谱背景严重干扰了稀土含量的测定。考察了NaCl对稀土含量测定的影响,实验结果表明:在基体不匹配的情况下,只有当钠盐浓度低于0.08 mol·L-1时,分光光度法可以准确测定萃余液中单一轻稀土(La,Ce,Pr,Nd)及中稀土(Sm,Eu,Gd)的含量,但不能准确测定重稀土的含量;而使用ICP-AES法,在NaCl浓度为0.001~1.0 mol·L-1条件下无法准确测定稀土含量。因此,实验室宜采用分光光度法在基体不匹配的条件下测定轻、中稀土含量,重稀土在基体匹配的条件下用电感耦合等离子体发射光谱法测定。     

High-pressure studies of optical dephasing in polymer glasses

The effect of high pressure on the optical dephasing of chromophores in organic polymers at low temperature is evaluated within the stochastic sudden jump two-level-system (TLS) model. The approximations within the "standard" TLS model cannot account for the observed pressure dependence of the pure dephasing rate without ad hoc assumptions about changes in the TLS density of states. However, the photon echo model of Geva and Skinner for disordered systems can be used to model pressure-dependent optical dephasing results for a variety of doped polymer systems without assuming changes in the TLS density of states. The relative importance of pressure-induced changes in TLS density, chromophore-TLS coupling, and TLS-phonon coupling is evaluated by fitting experimental high-pressure photon echo results to the TLS model.     

Structure of the water salt solutions of DNA with sulfonated scandium diphthalocyanine

Interaction of sulfonated scandium diphthalocyanine ScPc₂(SO₃)₄(NH₄)₄ with DNA in water salt solutions was studied by small-angle neutron scattering, dynamic light scattering, and atomic force microscopy. The results provide evidence about packaging of DNA molecules and agree with previous viscosimetry and spectrophotometry data.     

Effect of the length of surfactant hydrocarbon radicals on the association of cationic polyelectrolytes with alkyl sulfates in water-alcohol solutions

The effect of the lengths of the alkyl radicals of sodium alkyl sulfates (decyl sulfate, dodecyl sulfate, and tetradecyl sulfate) on the association with partially quaternized poly(4-vinylpyridine) in wateralcohol solutions of different compositions is studied via potentiometry, viscometry, spectrophotometry, and dynamic light scattering. The critical concentrations of surfactant association, hydrodynamic radii, and molecular-mass characteristics of polyelectrolyte-surfactant associates are determined. The parameters of the surfactant-polymer cooperative association and the dissociation constants of the complexes are calculated. An increase in the lengths of the alkyl radicals results in enhanced associative interactions in the polyelectrolyte-surfactant system at ethanol concentrations below 34 vol %. In solutions with higher alcohol concentrations, the composition of the solvent plays the decisive role in polymer-colloid complexation.     

Ag-CV的表面增强共振散射光谱研究

采用共振散射光谱和紫外可见光谱研究了银胶与结晶紫的相互作用。在ＰＨ为４．０的ＨＡｃ－ＮａＡｃ缓冲溶液中,奶胶在３４５ｎｍ和７００ｎｍ有两个共振散射峰;当加入带下辈民的阳离子染料结晶紫后,产生表面增强效应,３４５ｎｍ和７００ｎｍ处的共振散身信号大为增强,从而获得灵敏的表面增强共振散射光谱。     

Thermal lens spectrometric determination of hexavalent chromium

The applicability of thermal lens spectrometry (TLS) for quantification and routine determination of hexavalent chromium was investigated by using a collinear dual beam thermal lens spectrometer. In aqueous solutions the LOD of 0.1 μg l⁻¹ was obtained for Cr(VI) by using 160 mW laser power. The performance of the technique was verified by the determination of hexavalent chromium in standard reference water samples (NIST SRM 1643a and NIST SRM 1643c) and comparing the results for Cr(VI) in CCA (Cr, Cu, As)-treated timber extracts to concentrations obtained by atomic absorption spectrometry (AAS). Good agreement between the TLS results and reported values for Cr(VI) in SRMs as well as AAS results for Cr(VI) in CCA-treated timbers confirmed that TLS is a reliable and accurate analytical technique applicable for the determination of Cr(VI) in aqueous solutions at concentration levels 0.5–100 μg l⁻¹.     

Effect of the association of azo compounds on the results of the potentiometric determination of copper(II) in process solutions

The direct potentiometric determination of copper(II) using chalcogenide glass electrodes was studied in solutions containing azo dyes. The association of azo dyes, most pronounced in aqueous solutions of acid Blue 2K, was demonstrated by spectrophotometry. The interfering effect of reagent association on the results of the potentiometric determination of copper(II) was found.     

Quantification of nanodiamonds in aqueous solutions by spectrophotometry and thermal lens spectrometry

Spectrophotometry and thermal lens spectrometry were used to study solutions of several commercial detonation nanodiamonds. It was found that the absorption spectra of solutions of all studied nanodiamond samples obey the Bouger-Lambert-Beer law, which ensures the precise determination of the total mass concentration of unknown nanodiamond solutions using a calibration plot. It was shown that the absorption spectra of nanodiamond solutions exhibit both absorption and scattering components, both significantly affecting signal formation. Conditions were proposed for the spectrophotometric determination of nanodiamonds at 250 nm (l = 1.0 cm). The detection limits were from 60 ng/mL to 2 ??g/mL, depending on the nanodiamond type. Limits of detection of SDND nanodiamonds by spectrophotometry and thermal lens spectrometry were calculated for identical conditions of sample preparation and measurements (488 nm, l = 1.0 cm). These were 10 and 0.6 ??g/mL for spectrophotometry and thermal lens spectrometry, respectively (power of excitation radiation 150 mW).     

Influence of the fluoride ion on the aggregation and catalytic properties of micellar solutions of cetyltrimethylammonium bromide

The influence of the fluoride ion on the aggregation behavior and catalytic properties of neutral and alkaline aqueous solutions of cetyltrimethylammonium bromide in nucleophilic substitution reactions of phosphorus acid esters was studied by tensiometry, small-angle neutron scattering, and UV spectrophotometry. The critical micelle concentrations and the radii, aggregation numbers, and shape of micelles forming in these systems, as well as the kinetic parameters of the nucleophilic substitution reactions of phosphorus acid esters, were determined.     

Photon correlation spectroscopic and spectrophotometric studies of the formation of cadmium sulfide nanoparticles in ammonia–thiourea solutions

Nucleation of CdS in an aqueous ammonia solution of thiourea and cadmium chloride was studied by photon correlation spectroscopy (PCS), static light scattering, and spectrophotometry. The hydrodynamic diameter of nanoparticles, light scattering intensity, and optical density of the solutions increased with temperature and synthesis time. The processes of formation, growth, and coagulation of nanoparticles can be transferred from solution to the filter surface by continuously filtering the reaction mixture through a 200-nm filter.