Highly Sensitive Determination of Traces of Co(II) in Pharmaceutical and Urine Samples Using Kinetic–Spectrophotometric Method

Abstract

A high sensitive, accurate and simple kinetic method has been developed for determination of trace of Co(II) ions, based on its strongly catalytic effect in the reaction oxidation of disodium-6-hydroxy-5-[(4-sulfophenyl)azo]-2-naphtalenesulfonic acid (artificial color, Sunset Yellow FCF, E110 in text selected as SY) by hydrogen peroxide in borate buffer at pH of 9.5, by monitoring the rate of disappearance of SY. Reaction rate was monitored spectrophotometrically, at λ_max of the SY at 478.4 nm. The optimum operating conditions regarding reagents concentration and temperature were established. The tangent method was adopted for constructing the calibration curve, which was found to be linear over the concentration range 1.18–17.67 ng ml^?1 and 17.67–58.90 ng ml^?1 of Co(II). The limit of detection (3σ) is 0.15 ng ml^?1, and limit of quantification (10σ) is 0.5 ng ml^?1. The effects of the other ions on the reaction rate were determined for an assessment of the selectivity of the method. The developed kinetic procedure was successfully applied for the determination of Co(II) in pharmaceutical and urine samples. The unique features of this procedure are that the determination can be performed at room temperature, and the analysis time is short. The newly developed method is high sensitive, simple, inexpensive and efficient for use in the analysis of a large number of samples.     

Diode-pumped passively Q-switched yellow laser with SrWO4 Raman crystal and ceramic Nd:YAG gain medium

A diode-pumped passively Q-switched Nd:YAG/SrWO₄/KTP yellow laser is presented for the first time. As high as 1.02 W average output power was obtained at a pump power of 14.0 W with a pulse repetition frequency of 21.9 kHz and the corresponding diode-to-yellow conversion efficiency was 7.29%. The highest pulse energy of 56.2 μJ was obtained at a pump power of 7.2 W.     

酸性金黄偶氮染料在银镜上的表面增强拉曼光谱研究

以银氨溶液和葡萄糖制备的银镜为吸附基底,获得了酸性金黄G偶氮染料在银镜上的表面增强拉曼光谱,并对其拉曼峰的归属及吸附机理进行了探讨。酸性金黄G靠静电引力和范德华力以带孤对电子的N原子垂直吸附在银镜表面,SERS强度随染料浓度的降低而降低,检出限为10-10mol/L。     

多波长K系数分光光度法的应用研究

同时测定混合物中相互干扰的各组分含量,在很多领域具有实际意义。本文以食品中柠檬黄、日落黄、胭脂红测定为例,讨论了多波长K系数法在混合体系中的应用,效果良好。与多波长线性回归法相比,该方法准确度高,精密度也较好。     

Metals in water and surface sediments from Henan reaches of the Yellow River,China

The concentrations of Cd,Cr,Cu,Ni,Pb and Zn were determined in the water and surface sediments from the Henan reaches of the Yellow River.Twenty-three sampling sites along the Yellow River and its tributaries were selected.Generally,metal concentrations were found to decrease in sequences of Zn>Cu>Pb>Cr>Ni>Cd in water and Zn>Cr>Pb>Ni>Cu>Cd in sediments.High levels of metal concentration were determined at a few stations of the river and its tributaries,such as Yiluo River,Si River and Qin River.The pollutio...     

黄河甘宁蒙段表层沉积物中稀土元素形态和分馏作用研究

应用BCR连续提取法和高分辨电感耦合等离子体质谱(HR-ICP-MS)对黄河甘宁蒙段12个采样点(S1～S12)水体表层沉积物中14种稀土元素进行了含量测定及形态分析,并对稀土元素的分馏作用进行了研究。结果表明：各采样点表层沉积物中稀土元素的含量顺序均相同,且12个采样点14种稀土元素的平均含量(mg·kg-1)依次为铈(Ce, 66.4)>镧(La, 35.8)>钕(Nd, 28.6)>镨(Pr, 7.88)>钐(Sm, 5.87)>钆(Gd, 5.01)>镝(Dy, 4.53)>镱(Yb, 2.86)>铒(Er, 2.51)>铕(Eu, 1.31)>钬(Ho, 0.856) >铽(Tb, 0.760)>铥(Tm, 0.428)>镥(Lu, 0.404),与中国土壤背景含量相近;各稀土元素残渣态含量最高,约为71.9%～93.9%,表明生物有效性较低,对环境影响较小;可还原态含量较低,分布于0.20%～3.87%之间,均值为0.83%;弱酸提取态与可氧化态平均含量相近(7.69%和7.61%),玛曲采样点(S12)可氧化态含量(16.1%)明显高于弱酸提取态(1.73%),相关性分析结果表明总有机碳(TOC)含量与可氧化态含量之间有显著正相关关系,相关系数在0.763～0.914之间。稀土元素分馏作用研究结果表明：黄河甘宁蒙段表层沉积物中稀土元素主要来源于土壤风化,表现为轻稀土元素富集,Eu中度亏损。球粒陨石标准化图解曲线显示金沙湾(S8)和包头磴口(S1)二个采样点中La和Ce可能有外源稀土元素进入,且各采样点重稀土元素均有一定程度的外源影响。     

LD-pumped Nd:YAG/LBO 556 nm yellow laser

A new laser transition at 1112 nm was obtained after analyzing the parameters of the main laser transitions in Nd:YAG and calculating the transmission loss of the cavity at 1064, 1319, and 946 nm. The maximum output power of the fundamental wavelength was 610 mW, the fundamental wavelength light-to-light conversion efficiency was 38.1%, the maximum output at 556 nm was 109 mW intra-cavity frequency doubled by LBO, the SHG conversion efficiency was 17.8%, and the overall light-to-light efficiency was 6.8% for the pump power of 1.6 W.     

茜素黄GG共振光谱散射法测定人血清白蛋白

研究了酸性介质中茜素黄GG与人血清白蛋白(HSA)作用产生的共振光散射(RLS)现象.在pH=3.0附近RLS增强信号与一定浓度范围内的HSA呈线性关系,共振光特征峰在414nm.据此建立了一种测定HSA的新方法.线性范围0-5.0mg/L,检出限:24μg/L.     

LD泵浦Nd:YVO4/LBO腔内和频连续黄光激光器

用国产半导体激光二极管泵浦Nd:YVO4晶体,通过优化膜系,调节1064 nm谱线的线性损耗以达到与弱谱线1342 nm 增益匹配,在室温下实现1064 nm和1342 nm双波长连续运转,并通过Ⅰ类临界相位匹配LBO晶体腔内和频在国内首次实现593.5 nm黄色激光连续输出,当泵浦注入功率为1.8 W时和频黄激光最大输出达85 mW,光光转换效率为4.7%,功率稳定性24 h内优于±2.8%.