锇(Ⅳ)-KIO4-偶氮氯膦-pA催化光度法测定微量锇

在1.0 mol·L-1硝酸介质中,微量锇(Ⅳ)对KIO4氧化偶氮氯膦-pA的褪色反应有明显的催化作用,利用此反应可在水相中直接测定微量锇.锇(Ⅳ)含量在0.02～0.60 mg·L-1范围内符合比耳定律,检出限为0.01 mg·L-1.     

催化动力学光度法测定痕量锰

研究了在pH4.63的乙酸-乙酸钠介质中,Mn(Ⅱ)催化高碘酸钾氧化丁基罗丹明B的反应,建立了测定痕量Mn(Ⅱ)的催化动力学分析方法。方法线性范围为0~1.0μg/25mL,检出限为2.87×10-6g.L-1,用于水中Mn(Ⅱ)的测定,结果满意。     

示差光度法快速测定样品中高含量硅

根据硅钼蓝光度法原理,对高含量硅的测定条件进行了试验,采用示差光度法、反酸化处理、分段比色、标样紧密内插法等措施,试验出了能适用于各种系列样品中常量硅含量的快速测定方法。该方法准确、简便、快速、易掌握。     

气浮溶剂浮选光度法测定食品中痕量SO32-的研究

提出了碘溴化十六烷基三甲胺缔合体系溶剂浮选褪色光度法测定SO2-3 的新方法,方法的摩尔吸光系数ε365=3.0×105L·mol-1·cm-1,最大吸收波长为365 nm,测定5.0μg/50 mLSO2-3 6次,RSD为1.8%,线性范围为0~30μg/50 mL,方法应用于食品中SO2-3 的测定。     

催化溴酸钾氧化1-(2-吡啶偶氮)-2-萘酚动力学光度法测定痕量亚硝酸根

研究了在磷酸介质中,亚硝酸根对溴酸钾氧化1-(2-吡啶偶氮)-2-萘酚(PAN)的催化作用的反应条件,建立了测定亚硝酸根的动力学光度法。试验结果线性范围为0.2~8.0μg/25 mL,检出限为5.7μg.L-1,用于样品中亚硝酸根的测定,测定结果的RSD小于2.5%,回收率在101%~104%之间。     

用显示器测量人眼衬比度敏感函数

人眼视觉系统(HVS)特性是图像显示、处理和理解等理论与技术的重要依据,衬比度敏感函数(CSF)是描述视觉系统空间特性的主要指标之一。显示器作为图像信息输出的主要设备,显示器环境下人眼衬比度敏感函数数据更有实际应用价值。研究用阴极射线管(CRT)显示器测量人眼亮度衬比度敏感函数,详细描述采用10 bit图像显示卡产生亮度条纹衬比度达到人眼阈值的方法,提出采用多衬比度交互阈值确定(MITD)衬比度阈值的心理物理学实验方法。对矩形条纹的平均亮度10 cd/m26、0 cd/m29、0 cd/m2三个等级,0.41 cpd,0.82 cpd,1.23 cpd,1.97 cpd,3.08 cpd,3.79 cpd,4.93 cpd,7.04 cpd,9.86 cpd,16.43 cpd,24.64 cpd 11个空间频率和12名正常视力的青年进行了测量。测量结果与国内外采用光学装置方法测量结果进行了比较和讨论。     

Determination of Manganese with Triethanolamine Using Long-Path Photometry

Abstract

Manganese(II) in strongly alkaline medium in presence of triethanolamine (TEA) is readily oxidized to form an emerald green Mn(III)-TEA complex. The complex, long ago proposed by Bruno for a photometric determination, has a molar absorptivity of about one-tenth that of permanganate. However, when measured in a long-path cell this deficiency can readily be compensated for and the enormous advantages over the conventional method result, that chloride is no interference and boiling is not required. In order to employ the simplest available suitable instrument, especially for field work, an LED was used as a light source. Its peak wave length is somewhat off the absorbance maximum and a reinvestigation of linearity and interferences became necessary. Also investigated were some modifications proposed by Nightingale. They were found only to complicate but not to improve Bruno's simple procedure.     

Ant Colony Algorithm and Optimization of Test Conditions in Analytical Chemistry

The research for the new algorithm is in the forward position and an issue of general interest in chemometrics all along.A novel chemometrics method,Chemical Ant Colony Algorithm,has first been developed.In this paper,the basic principle,theevaluation function,and the parameter choice were discussed.This method has been successfully applied to the fitting of nonlinear multivariate function and the optimization of test conditions in chrome-azure-S-Al spctrophotometric system.The sum of residual square of the results is 0.0009,which has reached a good convergence result.     

Sodium Chloride Aerosol Generation Method for high Efficiency Particulate air Filter Testing

A method for submicron aerosol generation from the sodium chloride aqueous solution and the results related to the generation capacity and aerosol particle characterization as a function of the experimental conditions are presented.     

Frequency-selective absorbance detection: Refractive index and turbidity compensation with dual-wavelength measurement

A frequency-selective absorbance detection approach and its applications are described. First, a digital signal processor-lock-in amplifier (DSP-LIA)-based absorbance detector was evaluated. Compared to a simple operational amplifier (TL082CP)-based detector, the DSP-LIA-based detector showed lower noise levels, but the relative advantage was reduced under very low photocurrent levels (down to few nA). A 7 cm pathlength flow cell with this commercial LIA-based detector exhibited excellent Beer's law linearity (r² = 0.9999) and a noise level of 7 micro absorbance units (μAU). The limit of detection (LOD, S/N = 3) for methyl orange (MO) was 7 nM with this detector. Finally, as a more affordable alternative to an LIA, a balanced demodulator integrated circuit chip was used to fabricate a dual wavelength-frequency-selective LED-based absorbance detector. This device successfully compensated refractive index (RI) effect and turbidity effect in test flow systems. The LOD for MO with this system was 8 nM.