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从分光光度计杂散光测试原理出发,对我国目前在用的几种杂散光测试材料特性进行了分析。通过实验验证,指出了其中的不合理处,并提出了对杂散光测试材料特性的基本要求。 , 相似文献
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A copper-sensitive optical chemical sensor (optrode) is described. The optrode is based on a Nafion membrane and an immobilized organic ligand coupled with a flow injection (FI) system. The FI system includes a flow-through removable measuring cell and a simple spectrophotometer. Owing to the miniature size of the system and the efficient use of optical fibers, this optrode is well suited for monitoring environmental water samples. The success of the described optrode system depends on the effectiveness of the FI reagent delivery system. Optimum contact time with the membrane (as determined by the reagent flow rates) and the injected sample volume are critical. Environmental water samples were analyzed for copper content using the optimized optrode system. To validate the optrode's performance, the same water samples were analyzed using the atomic absorption spectrophotometer. 相似文献
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Results of using a field spectrophotometer and its appropriate protocols as a surrogate method for an oilfield produced water treatment process is presented. Methylene chloride extractions of the produced water before and after treatment maintained a yellow color pigment that was directly proportional to the hydrocarbon concentration. From this, an absorption spectrum and standard curve were developed. A resultant linear plot of the standard curve indicated that there is an excellent correlation (r2=0.9847) between the varying concentrations and the associated absorbance values at a wavelength of 400 nm. Total n-alkane concentration comparisons between the laboratory GC/MS analysis and the spectrophotometry analysis generated data of similar accuracy and precision at concentrations ranging from 1 to 137 mg/l (alpha=0.05). Linear comparisons between GC/MS and spectrophotometric coefficients were near unity, with the constant being near zero, with a correlation coefficient (r2) of 0.99. Based on this study, spectrophotometry is a complimentary method to GC/MS for determining total n-alkane concentrations in oilfield produced water samples. 相似文献
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A new and highly sensitive spectrophotometric method is developed for the determination of sub ppm levels of the widely used organophosphorus insecticide dichlorvos. The method is based on alkaline hydrolysis of dichlorvos to dichloroacetaldehyde followed by coupling with diphenyl semicarbazide (DPC) in alkaline medium. The absorption maxima of the wine red dye compound formed is measured at 490 nm. Beer's law is obeyed over the concentration range of 4.3 to 34 μg in a final solution volume of 25 mL (0.18–1.36 ppm). The molar absorptivity, Sandell's sensitivity and correlation coefficient were found to be 2.9 × 105 l mole?1 cm?1, 0.013 μg cm?2 and 0.9999, respectively. The standard deviation and relative standard deviation were found to be ± 0.007 and 1.90%, respectively. The lower limit of detection is 0.04 μg. The method is simple, sensitive and free from interferences of other pesticides and diverse ions. Other organophosphorous pesticides do not interfere with the proposed method. The method has been satisfactorily applied to the determination of dichlorvos in environmental and agricultural samples. 相似文献
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介绍了721型分光光度计,灯电源电路和稳压电路故障现象,分析了故障产生的原因,提供了排除故障办法,对该仪器维修提供了借鉴的经验。 相似文献
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通常测色分光光度计均由两个独立且完全相同的分光系统组成,为实现测色分光光度计小型化、轻量化,提出一种双光束分光系统设计。将传统的分光系统进行改进,使一个分光系统实现双光束分光系统的功能,用两个小狭缝代替一个狭缝,即可实现两束光谱同时探测。分析了双光束分光系统的工作原理及设计要求,设计了一个用于便携式测色分光光度计的分光系统。设计的Czerny-Turner结构双光束分光系统采用超环面成像镜,可以较好的校正像散,防止两束光谱串扰,两束光谱在探测器上完全没有重叠,光谱分辨率小于10 nm,谱面长度9.12 mm,体积仅为57 mm×54 mm×23 mm,满足设计指标要求。通过与相同设计指标的单光束分光系统比较得出,采用双光束分光系统的改进型测色分光光度计比传统的测色分光光度计减少了一整套分光系统,从而使体积大幅缩小。该方法特别适用于便携式测色分光光度计,也可适用于其他双光束分光光度计。 相似文献