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1.
在强酸性介质中,VO3与N-苯甲酰苯基羟胺(BPHA)反应生成紫红色络合物,能定量地被CHCL3萃取.萃取液加入2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5—Br—PADAP)后可发生配体交换反应,并生成橙红色的V(V)-5—Br—PADAP络合物,有机相可直接用于光度测定.V(V)-5—Br-PADAP的最大吸收波长为600nm,摩尔吸光系数为5.4X10 ̄4L·mol-1·cm-1,线性范围为0~0.76μgv/wl。  相似文献   

2.
合成了新试剂4-(H-酸偶氮)1-苯基-3-甲基吡唑酮(HPMP),研究了其和铜的显色反应。在pH=7的NH4Ac缓冲介质中,CTMAB存在下,HPMP与Cu(Ⅱ)生成2∶1紫色络合物,λmax=580nm,ε=5.68×104L·mol-1·cm-1。铜含量在0~0.6mg/L内符合比耳定律。方法用于水样和生物样品中铜的测定,结果令人满意。  相似文献   

3.
研究了8-羟基喹啉与NO^-2-碘胺重氮盐偶联反应的条件及其产物的极谱行为。二阶导数波高与NO^-2的浓度在0.002-0.2mg/L内呈良好的线性关系,回收率为98%-103%,已用于环境水样中NO^-2的测定。  相似文献   

4.
研究了NO2^--磺胺重氮盐与N,N-二甲基苯胺偶联反应的条件及产物在乙醇,NH3-NH4Cl(pH=10)介质中的极谱行为。二阶导数波高与NO2^--N浓度在0.0006-0.07mg/L内呈良好线性关系,回收率为97%-102%,已用于环境水中NO^-2-N的测定。  相似文献   

5.
钴 5-Cl-PADAB分光光度法天然水中钻含量很低,浓度多数为每升0.01-l卜g,对人、动植物不会产生毒害作用。有色金属冶炼厂和加工厂等企业的废水中常含高浓度的钻。水中钻的浓度为0.1-0.27mg/L时,对西红柿等植物产生毒害作用,硫酸钻浓度为...  相似文献   

6.
在十二烷基硫酸钠,氟化钠和盐酸羟胺存在下,PH=5.2~7醋酸-醋酸钠缓冲溶液中,Cu(Ⅱ),Fe(Ⅱ)分别与5-CI-PADAB形成紫红色络合物。选择测定波长为530nm,铜和铁的摩尔吸光系数分别为52×104L·mol-1·cm-1,60×104L·mol-1·Cm-1.铜和铁分别在0~12ug/10ml和0~10ug/10m1范围内符合比尔定律。选用了硫代硫酸钠-硫脲褪色液和EDTA掩蔽剂,直接用于血清及水中铜和铁的连续测定,结果满意。  相似文献   

7.
钼 催化极谱法   总被引:1,自引:0,他引:1  
钼 催化极谱法天然水中钼的含量为每升数微克。废水中铝的含量一般比较低。人和动物体内含银过多可使钙、磷和铜的代谢受到影响,发生病变。日本规定错的环境水质标准为0.07mg/L,使用ICP-AES或石墨炉原于吸收法测定。概述1.方法原理:在硫酸一二苯羟乙...  相似文献   

8.
研究了镉(Ⅱ)与4-(2-喹啉偶氮)-1,3-二羟萘(2-QADVM)的显色反应。结果表明:在0.3mnol/L氢氧化钠溶液中,当有十二烷基(2-羟乙基)二甲基氯化铵(DEMAC)存在时,镉(Ⅱ)与2-喹啉偶氮形成1:2橙红色络合物,λ_max为510_nm,摩尔吸光系数ε=1.2×105L·mol-1·cm-1,镉的浓度的在0~20μg/(25mL)范围内符合比尔定律,用2-喹啉偶氮作显色剂,可直接测定废水中的镉。试样用标准加入法测得回收率为96%~104%,相对标准偏差小于3%,用此法与双硫腙分光光度法对模拟镀镉废水进行了对比试验,其相对误差小于4%。  相似文献   

9.
高压蒸汽消化法测定废水化学需氧量的再研究   总被引:2,自引:0,他引:2  
用"自控式高压蒸汽消解器"作为高压蒸汽消化法测定废水化学需氧量的消化装置,详细研究了消化条件,最后确定,消化体系中(1/6)K2Cr2O7浓度为01mol/L,H2SO4浓度为10.1mol/L,催化剂Ag+浓度为0.03mol/L,消化温度为130℃,恒温时间为20min。用此方法和条件测定了12种单纯有机化合物和16种不同工业废水的化学需氧量,与标准回流法相比,相对误差在-5.5-6.0%之间。  相似文献   

10.
报道了利用N,N─二甲基苯胺为偶联试剂的Criess反应以示波极谱法测定NO_2~-的测试方法。在拟定的实验条件下,NO_2~-在4.0×10~-3~4.8×10~-1μg/ml范围内与极谱波波高呈良好的线性关系。环境水测定的相对标准偏差小于l%,回收率在97%~101%之间。  相似文献   

11.
Using previously established procedures that utilise linear free energy relationships, we estimated binding constants for the Windermere Humic Aqueous Model VII (WHAM/Model VII) for several radionuclide cations (Pd(2+), Sn(2+), U(4+), NpO(2)(2+), Pu(4+) and PuO(2)(2+)). This extends the number of cations that can be calculated with the model above the 40 included in the original Model VII work. When combined with equilibrium constants for inorganic species this allows the calculation of equilibrium distributions of chemical species under a wide range of conditions.  相似文献   

12.
为验证大气中SO2的浓度对气态H2O2自动荧光法监测的影响,设置了SO2与H2O2在自动荧光过氧化氢分析仪中的反应实验;同时,利用SO2和H2O2的反应速率公式进行了模拟计算,模拟计算结果与仪器的监测结果基本相符.证明了在大气SO2浓度较高的情况下,气态SO2对H2O2的自动荧光法测定确实会有显著影响,通过模拟计算的方法可对在线监测的H2O2浓度数据进行校正.  相似文献   

13.
水溶液中二氧化氯及系列氧化物的测定   总被引:7,自引:0,他引:7  
根据碘离子在不同pH值与ClO2、Cl2、ClO2-、ClO3-发生不同反应的原理,提出同时分析含氯系列氧化物的方法.相对标准偏差1.2%~6.5%,加标回收率可达92.6%~94.8%.该方法不仅可用于测定二氧化氯发生器产物各组分的浓度,还能用于测定给水和废水处理中的二氧化氯.  相似文献   

14.
被动采样监测环境空气中SO 2和NO 2   总被引:1,自引:0,他引:1  
用自主研制的采样管开展环境空气中SO2和NO2的被动采样监测.结果表明,被动采样监测结果与自动监测结果高度相关,经回归方程修正后,两者的结果没有显著性差异,被动采样的采样和分析产生的误差得以消除.  相似文献   

15.
16.
Indoor NO2 concentrations were measured in the kitchen, the living room and bedroom of 612 houses in two different areas in the Netherlands. In a group of housewives living in these homes, personal exposure to NO2 was measured. NO2 concentrations indoors were dependent on the presence or absence of (un)vented gas appliances. Personal NO2 exposure was only different between the two areas in the group with the lowest indoor concentrations. In this study, it was determined that gas appliances inside the house are the most important factor with respect to NO2 exposure and that outside NO2 concentration played a secondary role, except in situations where gas appliances were absent.  相似文献   

17.
废气中二氧化硫和硫化氢的气相色谱分析   总被引:1,自引:1,他引:1       下载免费PDF全文
试验了气相色谱法分离分析废气中高浓度二氧化硫和硫化氢的方法,用高分子多孔微球GDX 502为固定相,2m玻璃柱分离,火焰光度检测器检测,取得了分离效果好、峰形对称、分析速度快的测定效果。对色谱柱进行了选择,并讨论了柱管材质和担体对样品的吸附作用。  相似文献   

18.
Based on high spectral resolution infrared solar observations made at the International Scientific Station of the Jungfraujoch, Switzerland, total vertical column abundances of 18 atmospheric gases have been monitored routinely since 1984. The observed temporal evolutions in the columns of CH4, N2O, CO, CHClF2 (HCFC-22) and CF2Cl2 (CFC-12) are reported here as typical examples of this monitoring effort which is conducted within the frame of Global Change and Network for the Detection of Stratospheric Change programs.  相似文献   

19.
Effects of Cu2+, Pb2+ and Zn2+ were studied on voltage-activated Na-, Ca-, and K-currents in snail neurons. It was found that: 1. In normal physiological saline Cu2+, Pb2+ and Zn2+ ions exerted complex changes on the total ionic currents; 2. All three metal ion have depressed the inward Na-currents but with different K D , moreover Pb 2+ increased Na-current at low concentrations (5 M); 3. The inward Ca-current was also reduced. The sequence of the blocking effect of metals was different: Pb>Cu>Zn, however the steady-state inactivation was influenced only by Cu2+; 4. Outward currents were decreased in all neurons by Cu2+, but the effects of Pb2+ and Zn2+ were either depression or enhancement in different indentified neurons; 5. The possibility of binding heavy metals to wide variety of membrane proteins and the observed effects on different ionic channels suggest that the metal effect is complex and cannot be taken as a specific one to a single channel type or site of location.  相似文献   

20.
The goal of this paper is to compare and evaluate the performance of three air quality regulatory models for mercury releases. The models include Industrial Source Complex Short Term model (ISCST2), Industrial Source Complex Long Term model (ISCLT2), and SCREEN2. The evaluation is conducted in multiple point source urban environment using meteorological data, emission inventory and monitoring data for eight stations for the year 1990 to 1992. The performance of the models is evaluated using eight statistical parameters. The comparison of models results for both quarterly and annual averaging periods shows that ISCST2 predictions qualitatively match the observed concentrations; whereas SCREEN2 predicts highest concentrations and ISCLT2 the lowest concentrations. The summary of statistical analysis obtained by using three different methods of observed concentration (Co) and predicted concentrations (Cp) comparison show that the ISCST2 has a better overall performance than ISCLT2 and SCREEN2 models. However, none of the models met the criteria for a reasonable model. Summaries of 95% confidence limits on normalize mean square error (NMSE), geometric mean variance (VG) and geometric mean bias (MG) for each and among model indicate that of the three models, ISCST2 has the best overall performance indicators. Improved model performance may be achieved by incorporating different types of mercury forms into emission rate and air dispersion calculations.  相似文献   

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