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1.
采用离子交换树脂预处理工业废水方法测定微量Cr^6+,排除了Cr^3+、Fe^3+、Hg^2+等阳离子干扰,减除水中浊度、色度、免去冗长预处理手续,使原方法简便易行,回收率达90%以上。  相似文献   

2.
铬污染土壤中六价铬的测定   总被引:8,自引:0,他引:8  
于世繁  张国峰 《干旱环境监测》1996,10(4):207-208,241
研究了土壤中Cr^6+的提取测定方法。结果表明,用0.4mol/L KCl为提取剂,离心分离提取液,可简单,快速,准确地测定土壤中Cr^6+,所建立的方法适用于北方偏碱性土壤。  相似文献   

3.
离子色谱法测定水中主要阳离子   总被引:7,自引:0,他引:7  
报导了水中阳离子Li^+,Na^+,K^+,Ca^2+〉Mg^2+的离子色谱分析及其分析精密度,准确性和线性范围。与阴离子组分同时测定用于水中离子总量的分析,获得满意结果。  相似文献   

4.
停流──诱导动力学光度法测定微量钒   总被引:2,自引:0,他引:2  
Cr(Ⅳ)-Ⅰ-淀粉体系的氧化还原反应可被Cr(Ⅳ)-V(Ⅳ)反应所诱导,本文据此提出了一种测定微量钒(Ⅳ)的停流-诱导动力学光度法,并建立了测定最佳条件。常见离子中,除Fe2+,Tr1+,Se4+,As3+以外,大部分不干扰测定。本法测定钒(Ⅳ)的线性范围为0~1.8μg/ml;测定了土壤中微量钒,六次测定的RSD=2.45%。  相似文献   

5.
高氯离子废水COD的吸收测定方法研究   总被引:5,自引:0,他引:5  
本法基于可定星测定K2Cr2O7和Cl-的反应产物Cl2这一原理,在用吸收装置吸收Cl2后.用碘量法测定余氯,从而消除氯离子的干扰。本法具有较高的准确度和精密度。  相似文献   

6.
陈赋杏  李国刚 《干旱环境监测》1995,9(3):129-131,146
在强酸性介质中,VO^-3与N-苯甲酰基羟胺反应生成紫红色络合物,能定量地被CHCl3萃取。萃取液加入2--5-二乙氨基酚后可发生配体交换反应,并生生成橙红色的V-5-Br-PADAP络合物,有机相可直接用于光度测定。  相似文献   

7.
从CODcr废液中回收银及硫酸银   总被引:1,自引:0,他引:1  
从CODcr废液中回收银及硫酸银刘艳,张向东(石河子市环境监测站832000)用重铬酸钾法测定CODCr需加入硫酸银作催化剂。每测定一个水样需消耗约0.3g硫酸银,每升废液中约含2.1g硫酸银。含Ag+废水排入城市下水道,不仅污染环境,也是经济损失。...  相似文献   

8.
测定地面水中Cr6+的回收率问题的探讨马文英张占银(河北邢台市环境保护局,邢台054000)色度很深的水样,用锌盐沉淀分离法进行预处理脱色后还应消除氧化性物质方可进行C6+r测定,这是绝对不可忽视的一个关键。消除氧化性物质的处理步骤:水样置于150m...  相似文献   

9.
废水的BOD5测定中取稀释比是一个很重要的问题。本文根据数学推导得出BOD5测定中取稀释比的一种方法。BOD5/CODcr值在0.05-0.1,0.1-0.3,0.3-0.6,0.6-1.0四个范围内其稀释比f2可对应取55/CODcr、22/CODcr、9/CODcr、5/CODcr。  相似文献   

10.
石河子市地下水环境背景值   总被引:11,自引:0,他引:11  
采集并测定了石河子市19个地下水背景水样,分别确定了该市潜水和承压—自流水中K+、Na+、Ca2+、Mg2+、Cl-、SO、HCO、NO、F-、总硬度、矿化度、可溶性SiO2、COD、pH、Cu、Pb、Zn、Cd、Mn、V、Li、Mo、Se、Hg、I、As、Cr+5、C6H5OH、CN-、ABS的环境背景值.  相似文献   

11.
基于甲基橙(MO)在水体中和阳离子表面活性剂发生的褪色反应,采用分光光度法测定十六烷基三甲基溴化铵(CTAB),优化了试验条件,讨论了干扰物质的影响。MO与CTAB在10%乙醇-水溶液中反应形成淡黄色离子缔合物,以MO的最大吸收波长470 nm为测定波长,CTAB质量浓度在0 mg/L~13.1 mg/L范围内遵守朗伯-比尔定律,吸光系数为17.48 L/(g.cm),方法检出限为0.364 mg/L,标准溶液平行测定的RSD为2.3%,样品加标回收率为91.8%~107%。  相似文献   

12.
The increasing demand for environmental pollution control results in the development and use of new procedures for the determination of dangerous chemicals. Simple screening methods, which can be used directly in the field for a preliminary assessment of soil contamination, seem to be extremely advantageous. In our laboratory, we developed and optimized a rapid test for a preliminary evaluation of both the concentration and the mobility of some potentially toxic metals in soils. This screening test consists of a single extraction of the soil sample with a buffer solution, followed by the titration of the extracted solution with dithizone to determine the contents of bi-valent heavy metals (such as Pb, Cu, Zn, and Cd). This screening method was then directly applied in the field during the sampling campaign in the framework of an Italian–Serbian collaborative project, finalized in the study of metal availability in soils. The results obtained in the field with the rapid test were compared with those obtained in the laboratory following the conventional procedure commonly used to evaluate metal bioavailability (diethylenetriaminepentaacetic extraction). Moreover, selected samples were analyzed sequentially in the laboratory using the standardized BCR three-step sequential extraction procedure. The screening test gave results conceptually in good agreement with those obtained via the BCR procedure. These preliminary data show that the proposed screening test is a reliable method for the preliminary rapid evaluation of metal total concentrations and of potential metal mobility in soils, supporting sampling activities directly in the field.  相似文献   

13.
TCLP法对天津市农田重金属生态风险评价   总被引:1,自引:0,他引:1  
TCLP法是用缓冲剂提取重金属的一种方法,该法评价重金属生态风险在美国已开展多年。利用TCLP法对天津市某农田土壤重金属进行生态风险评价,结果表明,在采集的23个样品中有效态铜、铅、锌、镉的含量范围为1.13~5.26、2.11~5.22、2.60~30.6、1.09×10-3~77.9×10-3mg/kg,普遍低于铜、铅、锌、镉在土壤中的总量(22.1~66.8、21.2~50.6、56.8~445、0.04~0.20 mg/kg)。镉的TCLP有效态与总量的差别最大。锌、铅存在轻微污染,污染率分别为21.7%、4.3%。  相似文献   

14.
A new electrochemical adsorptive stripping voltammetry method was developed for the determination of trace amounts of copper in food and water samples. The study of electrochemical behavior of Cu ion indicated that Cu(II) and Schiff base formed a complex in H3BO4–NaOH buffer solution (pH?=?7.25). An accumulation potential of ?100 mV (vs Ag/AgCl) was applied while the solution was stirred for 60 s. The response curve was recorded by scanning the potential, and the peak current of ?0.31 V (vs Ag/AgCl) was recorded. The peak current and concentration of copper accorded with linear relationship in the range of 0.04–120 ng mL?1. The relative standard deviation (for 12 ng mL?1 of copper) was 1.73 %, and the detection limit was 0.007 ng mL?1. The possible interference of some common ions was studied. The proposed method was applied to the determination of copper in water, rice, wheat, tea, milk, and tomato with satisfactory results.  相似文献   

15.
In this study, an ultra-sensitive and highly selective, rapid flow-injection spectrophotometric method for the determination of iron (II) and total iron has been proposed. The method was based on the reaction between iron (II) and 2′, 3, 4′, 5, 7-pentahydroxyflavone in slightly acidic solution with a strong absorption at 415 nm. The carrier solution used was 1?×?10?5 M 2′, 3, 4′, 5, 7-pentahydroxyflavone in 0.1 M HAc/Ac? buffer solution at pH 4.5. Parameters that affect simultaneously the determination of iron (II) and interfering ions were tested. The relative standard deviation for the determination of 50 μg L?1 iron (II) was 0.85 % (n?=?10), and the limit of detection (blank signal plus three times the standard deviation of the blank) was 3 μg L?1, both based on injection volumes of 20 μL. The method has been successfully applied to the determination of iron (II) and total iron in water samples and ore samples. The method was verified by analysing a certified reference material Zn/Al/Cu 43XZ3F.  相似文献   

16.
针对EDTA滴定法测定水中总硬度(简称"标准法")时,存在的缓冲溶液配制繁琐、耗时长的问题,提出了缓冲溶液配制的改进方法(简称"改进法").改进法很好地克服了标准法的不足.通过地表水、地下水以及总硬度标准样品的比对测定,两法测定结果无显著差异.  相似文献   

17.
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   

18.
A simple and fast solid phase extraction procedure was developed to pre-concentrate traces of Cu and Zn prior to their determination in honey samples by flame atomic absorption spectrometry. The sample preparation included dissolution of honey samples and the passage (at 20 ml/min) of resulting 10 % m/v solutions (100 ml) through Dowex 50W?×?8-400 resin beds in order to quantitatively retain Cu and Zn and separate them from the glucose and fructose matrix. Enriched Cu and Zn traces were recovered with 5.0 ml of a 3.0 mol/l HCl solution and quantified by flame atomic absorption spectrometry. The procedure proposed was used to analyze sixty nine commercially available and freshly ripened honey samples coming from the Lower Silesia region (Poland). It enabled to measure Cu and Zn within the range of 0.01–1.42 and 0.03–15.38 μg/g, respectively, with precision better than 4 %. Accuracy, assessed on the basis of the recovery test and the comparison of results with those obtained using wet digestion and inductively coupled plasma optical emission spectrometry, was ranged from ?4 % to +6 %. Detection limits of Cu and Zn achieved with this method were 5 and 7 ng/g, respectively.  相似文献   

19.
采用常规酸消化方法分解锑渣和铋渣固体废弃物试样.处理后的消解液直接用ICP—AES法同时测定了Cu、Ph、Mn、Cr、Ni、和Zn等多种重金属元素。方法的精密度和准确度较好,适合于常规固体环境样品的分析。  相似文献   

20.
空气或废气中挥发性醛、酮的气相色谱法测定   总被引:3,自引:1,他引:3  
本文研究采用了空气或废气中挥发性醛、酮类化合物在常温下经2,4二硝基苯肼(DNPH)的酸性饱和溶液吸收,分别形成各自的腙,用CS2萃取后,经气相色谱法(GCFID)以3%SE30/ChromosorbWHP80100目为固定相和载体,分离测定,对空气或废气中的甲醛、乙醛、丙烯醛、丁醛、丙酮、丁酮、甲基异丁基酮等的测定,获得较满意的结果。  相似文献   

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