A Kinetic Spectrophotometric Method for the Determination of Iron （Ⅲ） in Water Samples

A new kinetic spectrophotometric method has been developed for the determination of iron (Ⅲ). The method is based on the catalytic effect of iron (Ⅲ) on the oxidation of weak acid brilliant blue dye (RAWL) by KIO4 in acid medium. The advantages of the proposed method are that it is sensitive, accurate, rapid, inexpensive, can be operated under room temperature and has a large determination concentration range compared to other techniques. The obtained optimum conditions are pH 3.15, RAWL (200 mgL-1) 5.00mL, Potassium periodate solution (0.01 molL-1) 0.30mL, phenanthroline (0.02molL-1) 1.00mL, reaction temperature 25℃ and reaction time 7 miu. With this method iron could quantitively be determined in the range 0.00-0.02 mgL-1, the detection limit being 4.10×10-10mL-1. The relative standard deviations (RSD) in five replicate determinations for 3 μgL-1 and 5μgL-1 iron (Ⅲ) are 3.1% and 1.9%, respectively. The method has been applied to the determination of iron (Ⅲ) in tap water samples and seawater samples (from the South China Sea), the recovery rates being 98.0% and 100.5%, respectively.     

New spectrophotometry for SZ cam (the problem of a third component)

We present the results of our spectroscopic observations of the eclipsing binary SZ Cam performed with the 1-m (Zeiss-1000) and 6-m (BTA) telescopes at the Special Astrophysical Observatory of the Russian Academy of Sciences in 2000 and 2003. Based on our results and published data, we have calculated new values for the component mass ratio, q = 0.72 ± 0.02, the radial velocity of SZ Cam relative to the Solar system barycenter, V ₀ =?10.6 ± 2.0 km s^?1, and the semi-amplitudes of the radial velocity curves for both components, K ₁ = 192.0 ± 2.6 and K ₂ = 266.4 ± 2.5 km s^?1. The orbital semimajor axes and masses of the components have been determined: α₁ = 10.4R _⊙, α₂ = 14.5R _⊙, M ₁ = 16.7M _⊙, M ₂ = 12.0M _⊙. New light elements and parameters of the radial velocity curve for the third body have been obtained. The mass of the secondary component of the third body M ₂ ^3b is discussed. Its lower limit is estimated to be M ₂ ^3b = 1.4M _⊙.     

偏最小二乘法用于多组分的分光光度分析——钙锶钡的同时测定

文章选用对Ca、Sr、Ba较灵敏的偶氮磺Ⅲ为显色剂,考察了其在不同体系下同Ca、Sr和Ba的络合行为,确定了光度法同时测定的最佳条件。采用偏最小二乘法(PLS)为数学模型,对络合物吸收光谱完全重叠的Ca、Sr、Ba进行了同时测定。方法用于合成样品和实际地质样品的分析,结果满意。     

Does chlorophyllidea reduce reliability of chlorophylla measurements in marine coastal sediments?

Pigment concentrations (chlorophylla, chlorophyllidea and pheopigmentsa) were measured by HPLC and spectrophotometry with acidification on 57 samples collected in different marine coastal sediments, containing autochthonous microphytes, and with various organic matter contents (plant detritus, biodeposits or hydrocarbons). Statistical analysis shows that the spectrophotometry with acidification, as compared to HPLC, gives reliable values for chlorophylla. Chlorophyllidea concentrations may be considered as negligible. Though spectrophotometric methods are sometimes questioned when applied to sediments they appear to give easy, quick and good estimates of Chla contents in benthic microphytes for hydrobiological studies in coastal areas.     

土壤中五氯酚的快速测定

针对五氯酚(PCP)污染土壤,根据NaOH与五氯酚反应生成五氯酚钠的原理,将不易溶于水的PCP与碱液反应生成易溶于水的盐类,从而达到从土壤中提取五氯酚的目的。用紫外分光光度法定量测定五氯酚含量,确定出最佳提取与分析条件。结果表明,PCP-Na合适的紫外吸收波长为319 nm;在300 r/min振荡时,最佳提取条件为提取液pH>12.5、土液比为1∶8(g/mL)、提取时间为20 min。在此条件下,加标回收率为91.2%~116.7%,最低检测限为2μg/mL。方法快速、简便,适合于农田土壤中五氯酚的现场检测。     

原子吸收分光光度法测定工业废水样品中的总铬

原子吸收分光光度计测定工业废水中的总铬,通过标准曲线的线性及方法的精密度和准确度验证表明,该方法简单、快速、准确,方法检出限为Ｃｒ：０．０３ｍｇ／Ｌ,可以满足工业废水样品中总铬的监测需要。     

钪的光度分析进展

文章介绍了我国１９８１－１９９２年钪的光度分析进展,列举了钪的光度显色剂和显色体系的特性及其应用。附参考文献５４篇。     

高浓度示差分光光度法测定钢厂循环管道除垢污水中的总磷

循环水及污水中总磷的国家标准方法是用分光光度法测定,当样品中有机磷含量高时,分解易碳化,操作繁琐,分析误差大.本文应用磷钼黄显色示差分光光度技术测定某钢厂循环管道除垢污水中的总磷,通过正交实验确立了采用硝酸-高氯酸消解样品,将样品中聚磷酸盐、有机磷酸盐转化为正磷酸盐,在硝酸溶液中,正磷酸盐与钒钼酸铵作用生成可溶性黄色磷钒钼酸配合物,基于其颜色强度与磷的浓度成正比测定高浓度磷的含量.实验对使用的氧化剂用量、溶解温度、显色条件、测定波长进行优化,结果表明,磷含量在10.0 ～ 40.0 mg/L范围符合朗伯-比尔定律,方法精密度(RSD)＜1.0％(n=5),加标回收率为98.8％～105.0％.建立的示差光度法比一般光度法相对误差小,准确度更高;与电感耦合等离子体发射光谱法的测定结果基本吻合,且测定成本更低.     

带形蜈蚣藻多糖和可溶性蛋白含量测定及藻红蛋白分析鉴定

用沸水浴的方法提取了带形蜈蚣藻(Grateloupia turuturuYamada)中的多糖成分,并用“苯酚-硫酸法”测定了其含量。用此法得到的多糖标准曲线,相关系数r=0.998 4,结果显示带形蜈蚣藻多糖质量分数为44.91%;利用Bradford法,测得60℃恒温干燥的带形蜈蚣藻可溶性总蛋白质量分数为0.33%;用简单的羟基磷灰石柱层析的方法分离了藻红蛋白,光谱检测证明为R-藻红蛋白,其在带形蜈蚣藻中的质量分数为0.114 5%。本实验测定方法可靠且简便易行。     

邻二氮菲分光光度法测定赤泥和石灰石混匀度

用盐酸提取赤泥和石灰石的混合料后,通过邻二氮菲分光光度法测定提取液中铁含量,进而求得混合料中氧化铁的质量分数,以此来衡量混匀度。结果表明,该法与重铬酸钾法比较,精密度和准确度均无显著性差异,测定混匀度的相对误差在±2%,且方法简便、快速、准确、对环境友好,可用于生产实时监控。