共查询到20条相似文献,搜索用时 125 毫秒
1.
以0.0030mol/LNaHCO-0.0024mol/LNa2CO3为淋洗液,离子色谱法测定土壤浸提液中的组分,Cl^-,NO^-3,SO^2-4三组分的相对标准偏差小于5%,加标回收率在90%以上,可以做多组分的同时测定,具有比较高的测试效率。 相似文献
2.
采用混合式厌氧反应器,以酒槽废水为基质,在厌氧体系中投加不同的浓度的SO^2-3,和Cl^-,研究盐离子日加入量和累积量与厌氧体系抑制程度的关系,得出维持厌氧体系正常运行把允许的日加入量(SO^2-4,低于144mg/L,Cl^-低于3195mg/L)和累积浓度(SO^2-4,低于300mg/L,Cl^-低于20000mg/L),研究了污泥对SO^2-4,和Cl^-的负荷,在SO^2-4/VS浓度 相似文献
3.
离子色谱法同时测定有机和无机阴离子 总被引:2,自引:0,他引:2
用离子色谱法同时测定有机阴离子和无机阴离子,实验中采用一种新型高容量分离柱,灵敏度高,选择性好。讨论了最佳实验条件的选择测定了F^-,Cl^-,SO4^2-,NO2^-,SeO3^2-、C2O4^2-、甲酸奶和乙酸根等阴离子,并且分析了沈阳地区雪样中的几种阴离子。 相似文献
4.
酸沉降与非金属建筑材料腐蚀机理的探讨 总被引:2,自引:0,他引:2
将酸雨对非金属建筑材料的整个腐蚀过程分为腐蚀初期,中期和末期3个腐蚀阶段,进而提出腐蚀机理。对整个腐蚀过程探讨表明:酸雨对材料的腐蚀是酸雨中H^+和SO4^2-共同侵蚀作用的结果;H^+将溶解硬化水泥中的Ca(OH)2,SO4^2-将与硬化水泥石作用生成膨胀性的物质CaSO4·2H2O。因此,酸雨对非金属建筑材料的腐蚀,主要是H^+引起溶解腐蚀和SO4^2-引起的膨胀腐蚀 。 相似文献
5.
6.
7.
8.
9.
地下水中硒存在形态的分析方法 总被引:3,自引:0,他引:3
本文采用含高浓度Mg^2+和SO4^2-的三种地下水样,在PH〈5条件下,地下水样中的SeO3^2-和SeO4^2-选择性地吸附于CuO颗粒物上,然后在PH=12.5时解吸。接着用HGAAS和IC法分别测出SeO3^2-,SeO4^2-浓度。并对二阶阳离子影响水中SeO4^2-的测定作了估算。 相似文献
10.
报道了一种简便的CC14体外引发自由基反应的模型,以小鼠肝匀浆脂质过氧化产物丙二醛(MDA)的OD532mm值(MDA-OD532mm)作为测定自由基反应的间接指标,研究了Hg^2+、Mn^2+、Ni^2+、Cr^3+、SeO3^2-等离子和Ss2O3水溶液在CC14引发自由基反应体系中的作用。结果表明:Mn^2+能显著抑制自由基的生成,Cr^3+有一定的抑制作用,而HgT^2+对自由基产生有明显促进 相似文献
11.
A method was developed for the determination of trace arsenic by spectrophotometry. The proposed method is rapid, simple,and inexpensive. This method can be used for sensitive determination of trace arsenic in environmental samples and especially in air particulates. The results obtained by this method as a proposed method were compared with those obtained by hydride generation atomic absorption spectrometry as a popular reported method for the determination of arsenic and an excellent agreement was found between them. The method was also used for determination of arsenic associated with airborne particulate matter and diesel exhaust particulates.The results showed that considerable amount of arsenic are associated with diesel engine particulates. The variation in concentration of arsenic was also investigated. The atmospheric concentration of arsenic was different in different sampling stations was dependent to the traffic density. 相似文献
12.
In this study we investigated the enrichment ability of oxidized multiwalled carbon nanotubes (MWCNTs) and established a new method for the determination of trace cadmium in environment with flame atomic absorption spectrometry.The MWCNTs were oxidized by potassium permanganate under appropriate conditions before use as preconcentration packing.Parameters influencing the recoveries of target analytes were optimized.Under optimal conditions,the target analyte exhibited a good linearity (R~2=0.9992) over the concentration range 0.5-50 ng/ml.The detection limit and precision of the proposed method were 0.15 ng/ml and 2.06%, respectively.The proposed method was applied to the determination of cadmium in real-world environmental samples and the recoveries were in the range of 91.3%-108.0%.All these experimental results indicated that this new procedure could be applied to the determination of trace cadmium in environmental waters. 相似文献
13.
大气颗粒物样品采集量较少,一般只有5~10mg左右,其中铂族元素含量很低并且受到Cu、Ni、Cd、Zr、Hf等元素的严重干扰,直接测定误差很大,必须要进行分离富集。因此,同时测定其中的微量元素及铂族元素非常困难。本文利用HF和HNO3在封闭溶样装置中对大气颗粒物样品进行消解,样品完全消解后,分取约1/4的样品溶液,以Ir作为内标元素等离子体质谱法测定微量元素,然后将剩余样品通过Dowex,50W X8阳离子树脂和P507萃淋树脂混合交换柱,分离基体元素及干扰元素,以Ir为内标等离子体质谱法测定Pt、Pd、Rh三个铂族元素以及Re和Au。实现了一次溶样同时测定大气颗粒物中的微量元素、稀有分散元素及铂族元素。国际标样结果稳定可靠。 相似文献
14.
煤中微量元素的环境效应 总被引:1,自引:0,他引:1
以华北某电厂燃煤为例,探讨了煤中微量元素的环境效应评价方法。通过电感耦合等离子体原子发射光谱(ICP-AES)等方法测定了电厂循环流化床炉原煤、飞灰、底灰中F,Pb,Hg,等11种微量元素的含量,通过淋滤实验测得了原煤及底灰中Pb、Hg、Cr等7种微量元素的淋出率,并测定了煤堆附近土壤中Cd、Hg、Cr等6种微量元素的含量,计算出了煤中微量元素对大气、水和土壤环境的污染因子。结果表明,燃煤中元素F、Hg、Se、Cl挥发性较强,燃煤中微量元素对大气环境的综合污染因子达3.5,属重污染。元素Hg、As的淋出率较高,原煤和底灰中微量元素对水环境的综合污染因子分别为0.71和0.88,污染程度属微污染。土壤对Cd、Hg、Pb等元素的富集程度很高,煤中微量元素对土壤环境的综合污染因子为0.98,属微污染。 相似文献
15.
16.
区域大气颗粒物干沉降采集及金属元素分析方法 总被引:14,自引:10,他引:4
以颗粒物为载体,从大气向水体、土壤和植被沉降的金属元素污染日趋严重.为了解其在京津冀区域的污染程度和沉降规律,利用聚氨酯泡沫膜片(PUF膜)为代用面,在区域内布设10个站点同步采集大气颗粒物干沉降.选择HNO3-H2O2-HF为消解酸体系,建立了微波消解-电感耦合/等离子体质谱(MAD-ICP/MS)测定其中20余种金属元素的方法,并通过分析2种国家标准物质的条件实验确定了优化的分析方案.结果表明,2007~2008年冬季京津冀地区大气颗粒物干沉降通量变化为85~912 mg.(m2.d)-1,其中河北保定地区金属元素沉降通量最高,兴隆最低;北京、天津和唐山市区明显高于郊区站点.地壳元素(A、lFe、Mn、K、Na、Ca、Mg)干沉降通量变化为151~16 034μg.(m2.d)-1,明显高于人为源元素(Cu、Pb、Cr、N i、V、Zn、Ba)1~3个数量级[14~243μg.(m2.d)-1];Zn和Ca分别是区域内干沉降通量最高的重金属和地壳元素,Mo、Co、Cd、As、Be沉降量较少;Pb和Zn出现明显富集. 相似文献
17.
Junming Guo Shichang Kang Jie Huang Mika Sillanpää Hewen Niu Xuejun Sun Yuanqing He Shijing Wang Lekhendra Tripathee 《环境科学学报(英文版)》2017,29(2):18-28
In order to investigate the compositions and wet deposition fluxes of trace elements and rare earth elements (REEs) in the precipitation of the southeastern edge of the Tibetan Plateau, 38 precipitation samples were collected from March to August in 2012 in an urban site of Lijiang city in the Mt. Yulong region. The concentrations of most trace elements and REEs were higher during the non-monsoon season than during the monsoon season, indicating that the lower concentrations of trace elements and REEs observed during monsoon had been influenced by the dilution effect of increased precipitation. The concentrations of trace elements in the precipitation of Lijiang city were slightly higher than those observed in remote sites of the Tibetan Plateau but much lower than those observed in the metropolises of China, indicating that the atmospheric environment of Lijiang city was less influenced by anthropogenic emissions, and, as a consequence, the air quality was still relatively good. However, the results of enrichment factor and principal component analysis revealed that some anthropogenic activities (e.g., the increasing traffic emissions from the rapid development of tourism) were most likely important contributors to trace elements, while the regional/local crustal sources rather than anthropogenic activities were the predominant contributors to the REEs in the wet deposition of Lijiang city. Our study was relevant not only for assessing the current status of the atmospheric environment in the Mt. Yulong region, but also for specific management actions to be implemented for the control of atmospheric inputs and the health of the environment for the future. 相似文献
18.
高温热水解-催化分光光度法测定植物样品中的痕量碘 总被引:1,自引:0,他引:1
建立了测定植物中痕量碘的高温热水解-催化分光光度法。设计了预处理程序以使植物样品能够稳定、彻底地进行热水解。通过正交实验优化了样品预处理的热水解参数:样品质量0.5g、氧气流量100mL/min、吸收液的NaOH浓度0.2mol/L、温度1100℃和热水解时间20min。为提高催化分光光度法测定吸收液中痕量碘的灵敏度,碘催化砷铈氧化还原反应的条件优化为:反应温度45℃、反应时间35min。该方法的检测限和定量下限分别为0.3ng/g和0.9ng/g,满足植物样品中痕量碘的分析要求。对国家标准植物样品的分析结果表明该方法准确度高、精密度好。由于使用的仪器都很常用、便宜,并具有测试费用低廉,检测限低、准确度和精密度高等优点,该方法易于推广使用,适合于植物样品碘含量的日常分析。 相似文献
19.
典型海洋大气环境当量加速试验环境谱研究 总被引:10,自引:8,他引:2
以典型海洋大气环境谱为基础,采用当量折算法,给出了各环境块参数的确定方法及加速谱与外场暴露环境的当量关系,编制了由紫外照射和周期浸润2个环境块构成的典型海洋大气环境加速试验环境谱.该谱的提出为水上飞机/水陆两栖飞机的选材和结构日历寿命评定提供了重要依据. 相似文献
20.
采集方法对氯化物沉积速率测试结果的影响 总被引:1,自引:0,他引:1
空气中氯化物的沉降速率是环境因素法评估大气腐蚀严酷度的一个重要因素,ISO9223标准规定的测试方法是使用湿烛法采集空气中的氯化物,而我国目前采用的方法是挂片法。文中同时使用湿烛法和挂片法采集万宁试验站近海暴露场大气中的氯化物并计算其沉积速率,每月采集一次,每次采集时间为1个月,连续采集11次,对这两种方法的测试结果是否一致进行了研究。研究表明:当显著水平为0.01时,湿烛法和挂片法具有明显的差异,挂片法确定的氯离子沉积速率等级可能要比湿烛法所确定的高一级。 相似文献