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1.
研究了碱提取吹扫捕集气相色谱冷原子荧光光谱法测定沉积物中甲基汞的影响因素,包括载气流速、柱温、衍生化试剂、样品称取量、前处理时碱性提取液加入量和反应瓶中提取液加入量的影响,分析了提取液加入量对Tenax管的影响、提取液保存的影响因素、沉积物样品保存的影响因素以及样品中Hg2+的干扰影响。根据影响情况确定最佳测定条件,应用于广西龙江河流域上9个代表性监测断面的底泥样品中甲基汞的测定,采用污染指数法对该流域甲基汞的污染现状进行评价。结果表明,最佳载气流速范围为22~27 mL/min,最佳柱温为46℃。衍生化试剂选择四乙基硼化钠和四丙基硼化钠均能达到较好的回收率。样品称取量选择0.50 g时回收率好。前处理时碱性提取液的加入量对甲基汞的提取效率没有显著影响。为保证水相衍生反应体系最终pH在5左右,乙酸-乙酸钠缓冲溶液的加入量随提取液加入量的增加而增加。当缓冲溶液为300μL时,提取液小于150μL不会影响Tenax管性能。避光与否对提取液的保存和样品的保存影响都不大,提取液保存3 d后、样品保存15 d后,甲基汞回收率将低于80%。衍生化前定量体积提取液中Hg  相似文献   

2.
高效液相色谱法测定土壤中阿维菌素残留   总被引:1,自引:0,他引:1       下载免费PDF全文
采用高效液相色谱法紫外检测器测定土壤中的阿维菌素残留,选择丙酮为提取剂、二氯甲烷为萃取剂,优化了色谱条件.方法在0 mg/L~12.1 mg/L范围内线性良好,检出限为0.014 mg/kg,空白土壤加标样品平行测定的RSD≤6.5%,回收率为78.6%~83.1%,残留试验表明阿维菌素在土壤中消解速率较快.  相似文献   

3.
建立了测定土壤中高氯酸盐的离子色谱法,通过前处理条件优化和色谱条件优化形成准确高效的测定方法,并采集实际土壤样品进行实验验证。称取 1.00 g土壤样品,用20 mL超纯水混合均匀,超声提取40 min,离心后采用水系微孔滤膜过滤的前处理方式,土壤中高氯酸盐的加标回收率最稳定;在淋洗液浓度和流速都满足测定条件的前提下,为了缩短高氯酸盐的保留时间,避免复杂基质干扰,延长淋洗液发生器的使用寿命以及保护色谱柱,选择淋洗液浓度为40 mmol/L,流速为1.0 mL/min。在优化条件下,高氯酸盐的方法检出限为0.04 mg/kg。实际样品加标中高氯酸盐的相对标准偏差为1.9%~8.8%,加标回收率为91.0%~106%,结果表明离子色谱法测定土壤中高氯酸盐简单、灵敏、快速。  相似文献   

4.
在室温低于 1 5℃的条件下 ,用重量法测定苯可溶物时 ,恒温水浴 90℃的加热条件 ,无法使苯蒸馏物回流到提取器中 ,在上行支管处便冷凝后直接回流到蒸发瓶。解决这一问题的办法 :1在上行支管处加保温层 (可用脱脂棉、滤纸、胶布等缠绕 )。2将恒温水浴提高到 93℃。3间歇启用排风机。在使用排风机时 ,需将恒温水浴提高到 95℃以上。在低温条件下重量法测定苯可溶物@刘文凯$河北省环境监测中心站!河北石家庄050051  相似文献   

5.
采用气相色谱法测定土壤和植物中的毒鼠强,用苯作为提取剂,中性氧化铝-硅镁柱净化。土壤和植物的回收率分别为84.0%~87.0%8、1.4%~86.0%,样品最低检出量为20ng/g。  相似文献   

6.
采用加速溶剂萃取-高效液相色谱法探究土壤和沉积物中11种均三嗪类农药测定相关保存条件。结果表明,在4℃以下避光、密封,标准贮备液可保存60 d;标准曲线系列溶液可重复使用11 d;阿特拉津等6种化合物的土壤样品可保存20 d,其他化合物可保存5 d~12 d;经过冷冻干燥处理,阿特拉津等7种化合物的沉积物样品可保存8 d,其他化合物可保存12 d;土壤提取液至少可保存60 d。  相似文献   

7.
采用碱性微波提取法处理土壤样品,用电感耦合等离子体质谱(ICP/MS)法测定试样中的六价铬,以标准物质测定相对误差的绝对值作为试验指标建立正交模型,确定碱性微波消解的提取温度95 ℃、提取时间30 min、氯化镁用量005 g、提取液体积6 mL为最佳试验条件,采用He碰撞池技术和在线内标分别消除基体带来的质谱和非质谱干扰。条件优化后,方法检出限为0.10 mg/kg,实际样品6次测定结果的RSD分别为13.0%和5.7%,加标回收率为120%和106%。将该方法用于有证标准土壤样品的测定,测定结果均在标准值范围内。  相似文献   

8.
通过固相萃取法提取地表水中10种氨基甲酸酯类农药,萃取溶液经浓硫酸脱色,佛罗里硅土柱除杂,用柱后衍生高效液相色谱法测定.在5μg/L~500μg/L范围内,标准曲线线性关系良好,仪器检出限低于1μg/L,水样平均加标回收率为90.0%~101%,RSD为1.1%~9.2%.  相似文献   

9.
研究了废弃泥浆中的Cr(VI)提取测定方法并与土壤的浸提方法进行比较。结果表明,用0.1mol/L的KH2PO4为提取剂高速搅拌离心,分离提取液,可简单、快速、准确地测定废弃泥浆中的Cr(VI)。该方法的相对标准偏差为0.6%~2.5%,加标回收率86%~98%。  相似文献   

10.
化学法测定工业废水中氰化物 ,干扰物质较多 ,通常需作蒸馏预处理 ,用离子色谱法测定则简单得多。水样采集后 ,立即加入氢氧化钠 ,使氰化钠水解生成甲酸钠 ,用HPICAS4阴离子柱分离 ,0 0 0 50mol/LNa2 B4O7·H2 O作淋洗液 ,抑制型电导检测器进行测定 ,由HCOONa的质量浓度可得出CN-的质量浓度。用此方法测定CN- ,灵敏度较低 ,为mg/L级。改用 1 4 7mmol/L乙二胺、1 0mmol/LNa2 H2 BO3、1 0mmol/LNa2 CO3作淋洗液 ,同样分离柱分离 ,电导检测器测定 ,可达到 μg/L级。离子色谱法测定氰化物的改进@董国强$肥城市环境监测中心站!山…  相似文献   

11.
我国沙尘暴灾害及其治理对策初步研究   总被引:4,自引:0,他引:4  
分析研究了沙尘暴的成因、时空分布、发展趋势及造成的灾害,结合国外经验提出了我国治理的对策建议。  相似文献   

12.
李江 《干旱环境监测》2006,20(4):246-248
针对目前室内环境监测工作出现的种种问题,就如何规范的开展室内环境监测工作,更好地为社会提供真实、准确、有效的监测数据,本文提出相关的探讨。  相似文献   

13.
The social and economic implications of atmospheric change on biodiversity need to be seen in a global context of major shifts in the conceptualization and management of our relationship with nature. Traditionally, we have conceptualized the atmosphere and the other creatures of the biosphere as separate from the human, but their quasi-autonomy is now becoming subject to more and more human management. This raises not only economic issues, but social, political, and ethical concerns that will have substantial influence on public policy. Among these are the commodification of genetic material; the privatization of traditional knowledge; and the management of information. In this broader context, the paper examines an array of current and proposed strategies of response to changes in biodiversity as a result of climatic and other stresses.  相似文献   

14.
Canada responded to the Global Biodiversity Convention by completing the Canadian Biodiversity Strategy in 1995. At the same time, Environment Canada also completed a national Science Assessment on Biodiversity. During this period, the Smithsonian Institution, in partnership with Parks and Environment Canada, initiated the implementation of a global biodiversity monitoring program in Canada. Under the auspices of the United Nations Man and the Biosphere Program, the SI/MAB monitoring protocols and plots have spread across Canada at an unprecedented rate. National champions in the science and educational sectors, working within an inter-disciplinary ecological framework, have guided the development, education, quality control and sharing of atmosphere-biodiversity observations electronically.Atmospheric-Biodiversity Networks and Networking have traditionally operated within separate mandates with little degree of integration. Air-Bio Networks were designed within an integrated framework to better understand the atmospheric stress on biodiversity and the adaptation actions, nationally and regionally. Detailed examples of the cumulative effects of climate change, stratospheric ozone depletion, acid deposition, ground-level ozone, suspended particulate matter and hazardous air pollutants on biodiversity will be discussed using a Southern Ontario case study. In addition, recommendations will be presented for future paired SI/MAB plots, linked networks and networking for adaptation within the context of climate, chemical and ecological gradients.  相似文献   

15.
针对太原市空气臭氧污染较为严重的问题,开展臭氧主要前体物醛酮化合物质量浓度及其变化规律研究.利用2,4-二硝基苯肼固相吸附/高效液相色谱方法,通过对太原市2019年冬季和夏季大气的醛酮化合物进行分析,发现太原市冬季总醛酮化合物的平均质量浓度为13μg/m3,低于夏季的27μg/m3.其中甲醛、乙醛和丙酮质量浓度最高,且...  相似文献   

16.
A simple and accurate method of determining metalaxyl and cymoxanil in pepper and soil was developed by ultra-performance liquid chromatography–photodiode array detection. The limits of detection were 0.015 mg/kg for metalaxyl and 0.003 mg/kg for cymoxanil. The limits of quantification were 0.05 mg/kg for metalaxyl in pepper and soil as well as 0.01 mg/kg for cymoxanil in pepper and soil. Recoveries of pepper and soil were investigated at three spiking levels and ranged within 77.52 to 102.05 % for metalaxyl and 87.15 to 103.21 % for cymoxanil, with relative standard deviations below 9.30 %. For field experiments, the half-lives of metalaxyl were 3.2 to 3.9 days in pepper and 4.4 to 9.5 days in soil at the three experimental locations in China. At harvest, pepper samples were found to contain metalaxyl and cymoxanil well below the maximum residue limit MRLs of the European Union (EU) following the recommended dosage and the interval of 21 days after last application.  相似文献   

17.
A simple and accurate method for the determination of bismerthiazol and its metabolite 2-amino-5-mercapto-1,3,4-thiadiazole was developed in Chinese cabbage and soil by high-performance liquid chromatography-diode array detection in this study. The limits of detection were 0.06 mg/kg for bismerthiazol and 0.03 mg/kg for 2-amino-5-mercapto-1,3,4-thiadiazole, respectively. Recoveries of cabbage and soil were investigated at three spiking levels and were in the range of 84.0–96.0 % for bismerthiazol and 71.0–74.6 % for 2-amino-5-mercapto-1,3,4-thiadiazole, with relative standard deviations below 7.0 %. For field experiments, the half-life of bismerthiazol was 2.4–2.5 days in Chinese cabbage and 2.5–4.8 days in soil at the two experimental locations in China. Dissipation residues of 2-amino-5-mercapto-1,3,4-thiadiazole were lower than 0.72 mg/kg. Terminal residues of bismerthiazol and its metabolite were less than 3.0 and 0.3 mg/kg in Chinese cabbage, respectively. No bismerthiazol or metabolite residues were detected in soil on days 5, 7, 10, and 14 after the last spraying at the two dosage levels.  相似文献   

18.
阐述了环境监理与环境管理的关系,指出了以制度和程序规范两者的分工与合作可充分发挥环境监理在环境管理中的作用  相似文献   

19.
废旧干电池的环境污染防治及回收利用   总被引:5,自引:0,他引:5  
王颖 《干旱环境监测》2002,16(2):113-115
介绍了各种干电池的基本化学组成,分析了废旧干电池污染环境的主要途径及对人类的危害,并就回收利用问题提出建议。  相似文献   

20.
A simple residue analytical method using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) procedure for the determination of trifloxystrobin and its metabolite trifloxystrobin acid (CGA321113) in tomato and soil was developed using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The limits of detection were 0.0005 mg/kg for trifloxystrobin and 0.001 mg/kg for trifloxystrobin acid, respectively. The average recoveries in tomato and soil ranged from 73–99 % for trifloxystrobin and 75–109 % for trifloxystrobin acid, with relative standard deviations below 15 %. The method was then used to study the dissipation and residues in tomato and soil. The dissipation half-lives of trifloxystrobin in tomato were 2.9 days (Beijing) and 5.4 days (Shandong), while in soil were 1.9 days (Beijing) and 3.0 days (Shandong), respectively. The final results showed that the major residue compound was trifloxystrobin in tomato whereas it was its metabolite, trifloxystrobin acid, in soil. The final residues of total trifloxystrobin (including trifloxystrobin acid) were below the EU maximum residue limit of 0.5 mg kg?1 in tomato 3 days after the treatment.  相似文献   

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