共查询到19条相似文献,搜索用时 78 毫秒
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用分光光度法测定水中溶解氧 总被引:3,自引:0,他引:3
测定水中溶解氧的经典方法是碘量法(滴定法)[1]。本文采用一种新方法——分光光度比色法测定水中溶解氧,该法经实验验证是可行的。1方法原理水样中溶解氧加入硫酸锰后,在碱性条件下将低价态锰氧化成高价态锰,然后在酸性条件下高价锰又将碘负离子氧化析出橙黄色游离碘。反应过程为:依据以上化学反应用分光光度法测定I2的吸光值,即可求得水样中溶解氧值。2试剂和仪器硫酸标溶液、碱性碘化钾溶液、硫酸均同碘量法[1]。固体碘(GR),碘化钾。721型分光光度计。3测定步骤3·1标准曲线的绘制称取12.700gI2和40gKI溶于1000ml蒸馏水中,… 相似文献
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异相平衡流动注射分光光度法测定水中痕量SO^2—4 总被引:2,自引:0,他引:2
根据异相平衡的原理,确立了用流动注射分光光度法测定水样中痕量SO^2-4的新方法。利用Ba(Ⅱ)与偶氮氯磷Ⅲ的二元络合显色反应及BaSO4=Ba^2++SO^2-4进入微溶化合物BaSO4反应柱前后吸光值的改变,从而求得SO^2-浓度。表观摩尔吸光系数ε=2.3*10^4L.mol^-1.cm^-1,SO^2-4检的线性范围为0-40mg/L,检测限为0.80mg/L,相对标准偏差为1.2%,试 相似文献
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试验了碘的倍增反应用于微量碘的测定,用淀粉指示剂显色,最大吸收峰位于620mm,摩尔吸光系数可达1×105L·mol-1·Cm-1.0~6μg碘/10ml符合比耳定律,可用于盐湖水、矿泉水、油田水和食盐、海产品中微量碘的测定. 相似文献
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溶剂浮选吸光光度法测定工业废水中痕量酚 总被引:1,自引:0,他引:1
本文拟定了以CPB(溴化十六烷基吡啶)为捕收剂,正戊醇为有机溶剂,浮选苯酚偶氮盐的溶剂浮选吸光光度法测定痕量苯酚的方案.表观摩尔吸光系数为2.6×106Lmol-1.Cm-1,检测下限为0.2pPb,用于炼油厂总排污水中苯酚的测定,7次的相对标准偏差为0.6%。 相似文献
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氧化偶氮胂M褪色光度法测定微量锰的研究 总被引:1,自引:0,他引:1
在酸性介质中,Mn(Ⅶ)强的氧化性对偶氮胂M有褪色作用,借此进行吸光光度法测定微量锰的研究。实验表明,在18~27mol/LH2SO4介质中,有色溶液的最大吸收波长为540nm,表观摩尔吸光系数为183×104L/mol·cm,锰量在0~14μg/ml范围内与有色溶液吸光度的减少值呈线性关系。方法简单快速、选择性好、准确度高,灵敏度是高锰酸盐法的近8倍,可用于测定水样、地质样品中的微量锰。在测定某些地质样品中的微量锰时,结果满意。 相似文献
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方忻兰 《环境监测管理与技术》1995,(6)
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
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高效液膜分离富集测定微量铜 总被引:1,自引:0,他引:1
应用高效乳状液膜技术分离、富集水和土壤样品中微量铜(Ⅱ).研究了流动载体(P204)、表面活性剂(SPan80)、膜的增强剂(液体石蜡)、膜溶剂(煤油)和内相解吸剂(2.5mol/LH2SO4)等液膜体系,对分离富集微量铜(Ⅱ)的影响.确定了Span80—P204─液体石蜡─煤油─H2SO4高效液膜体系的最佳组成和最适宜的实验条件.富集后的溶液用1-(2-吡啶偶氮)-2-萘酚(PAN)分光光度法测定铜(Ⅱ).用本法富集水和土壤中微铜(Ⅱ).回收率在99%以上。应用于测定水和土壤中的微量铜.相对标准偏差为1.2%~4.5%。 相似文献
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meso-四(3-氯-4-甲氧基苯基)卟啉二阶导数分光光度法测定废水中痕量汞(Ⅱ) 总被引:4,自引:0,他引:4
本文基于Hg(Ⅱ)meso四(3氯4甲氧基苯基)卟啉(T(3Cl4MOP)P)Twen80显色体系,提出一种高灵敏度二阶导数分光光度法测定工业废水中的痕量汞(Ⅱ),研究了汞配合物的形成条件。在pH72~79的中性介质中和Tween80的存在下,沸水浴加热6min,反应进行完全。汞(Ⅱ)量在18~104μg/L范围内符合比尔定律,二阶导数分光光度法测定汞(Ⅱ)的表观摩尔吸光系数ε4526,4616=988×106L·mol-1cm-1,检出限为18ng/ml。方法用于工业废水中痕量Hg(Ⅱ)的测定,结果满意。 相似文献
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TOA—苯体系萃取分离—原子吸收法测定环境水样中铬(Ⅲ)和铬(Ⅵ) 总被引:2,自引:0,他引:2
研究了三正辛胺(TOA)-茉体系对Cr(Ⅲ)和Cr(Ⅵ)的选择性萃取作用,在硫酸介质中可将水相中的Cr(Ⅵ)萃取到有机相里,而Cr(Ⅲ)仍留在留在水相中,用原子吸收法(AAS)测定可求得Cr(Ⅲ)和Cr(Ⅵ)的含量,回收率分别为94% ̄105%和94% ̄104%。方法简单、快速、准确。 相似文献
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铬渣样品以(1+10)磷酸溶液加热消解1.5h,可得到完全澄清的消解液。采用恒电流库仓滴定法测定消解液中的Cr(Ⅵ),测得值(1.64%)与标样参考值(1.7%)接近,准确度高,相对标准偏差为0.98%。适于铬渣中Cr(Ⅵ)的日常监测。 相似文献
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本文介绍一个简单而灵敏的催化分光光度法,用于测定环境样品中微量碘,本法系基于亚硝酸根存在时微量碘离子催化还原硫氰酸铁络含物,并以分光光度计测量该红色络合物的减弱强度,在一定温度时,该络合物的分解速度正比于磺的含量.在给定的实验条件下,磺离子的浓度在0.001-0.024毫克/升之间服从比尔定律. 本法已成功地应用于天然水、土壤、海底泥和海生物中微量磺的测定,结果良好. 相似文献
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Huang Z Ito K Morita I Yokota K Fukushi K Timerbaev AR Watanabe S Hirokawa T 《Journal of environmental monitoring : JEM》2005,7(8):804-808
Using a novel high-sensitivity capillary electrophoretic method, vertical distributions of iodate, iodide, total inorganic iodine, dissolved organic iodine and total iodine in the North Pacific Ocean (0-5500 m) were determined without any sample pre-treatment other than UV irradiation before total iodine analysis. An extensive set of data demonstrated that the iodine behaviour in the ocean water collected during a cruise in the North Pacific Ocean in February-March 2003 was not conservative but correlated with variations in concentrations of dissolved oxygen and nutrient elements such as silicon, nitrogen and phosphorus. This suggests that the vertical distribution of iodine is associated with biological activities. The dissolved organic iodine was found in the euphotic zone in accord with observations elsewhere in the oceans. The vertical profile of dissolved organic iodine also appears to be related to biogeochemical activity. The concentrations of all measured iodine species vary noticeably above 1000 m but only minor latitudinal changes occur below 1000 m and slight vertical alterations can be observed below 2400 m. These findings are thought to reflect the stratification of nutrients and iodine species with different biological activities in the water column. 相似文献
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Saqer AS Seham H Ragaa G Yehia Ael W Wafaa S 《Environmental monitoring and assessment》2007,130(1-3):341-346
Strongyloidiasis presents a major health hazard when reusing wastewater. Albendazol with a concentration of 4 mg/l, a contact time of 45 min,
pH 1.2 and pH 10.2, killed the larva. The larva was also killed with a 0.03% concentration of iodine and a detention time
of 30 min or a 0.04% concentration of iodine and a contact time of 10 min. The required detention time to inactivate larva
in water was found to be 17 days. The minimum revealed residual chlorine to kill the larvae was 4 mg/l with 120 min of detention
time, and a minimum contact time was found to be 80 min with a residual of 23 mg/l. Many methods are available to inactivate
the Strongyloides stercoralis, which could be acids, alkaline chemicals, larvicidal chemicals, super chlorination, or just detention time. The best method
must be determined according to the prevailing specific environmental site and the feasibility of the selected method(s). 相似文献
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A. Farmany A. Khosravi S. Abbasi J. Cheraghi R. Hushmandfar S. Sobhanardakani H. Noorizadeh S. S. Mortazavi 《Environmental monitoring and assessment》2013,185(1):553-558
A new kinetic method has been developed for the determination of iodine in water samples. The method is based on the catalytic effect of I? with the oxidation of Indigo Carmine (IC) by KBrO3 in the sulfuric acid medium. The optimum conditions obtained are 0.16 M sulfuric acid, 1?×?10?3 M of IC, 1?×?10?2 M KBrO3, reaction temperature of 35°C, and reaction time of 80 s at 612 nm. Under the optimized conditions, the method allowed the quantification of I? in a range of 12–375 ng/mL with a detection limit of 0.46 ng/mL. The method was applied to the determination of iodine in river and city water samples with the satisfactorily results. 相似文献
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张迪生 《环境监测管理与技术》2014,26(2):60-62
采用定电位电解法测定固定污染源废气中SO2,根据CO标准气体干扰SO2 测定的规律建立数学模型,并在实验室用CO标气对数学模型进行验证.用该数学模型对5家企业固定污染源废气中SO2 监测,将测定结果与碘量法的测定结果比对,绝对误差与相对误差在允许范围内. 相似文献