还原荧光法测定水和废水中的对硝基酚

本文用乙酸丁酯萃取水和废水中的对硝基酚,用氢氧化钠溶液反萃取,然后用硼氢化钾还原对硝基酚为对氨基酚,用荧光法进行分析测定。荧光激发波长和发射波长分别为274nm和372nm。检测限为3.0μg/L。样品加标回收率为89％～96％。     

银盐分光光度法测定水和废水中的元素磷

本文拟定一种新的分光光度法分析水或废水中的元素磷(黄磷)。水中元素磷经有机溶剂萃取后,与硝酸银溶液反应,生成亮黄色溶液,直接进行分光光度测定。检测下限0.01μg黄磷;相对标准偏差0％～8％;回收率88％～100％。方法简单、快速、选择性好、精密度和准确度高,无毒,安全。     

用石墨炉原子吸收法测定水质中微量砷,硒的探讨

采用石墨炉原子吸收法测定水中微量砷，硒，经大量实验条件摸索，选择不同仪器分析工作条件，找出了最佳升温程序条件，特别是原子化时气流控制，使分析方法的检出限降低为：Ａｓ０．６μｇ／Ｌ，Ｓｅ０．５μｇ／Ｌ。线性范围；Ａｓ０．０００－０．１２０ｍｇ／Ｌ，Ｓｅ０．０００－０．０２４ｍｇ／Ｌ；精密度，相对标准偏差分别为：Ａｓ１．２６％，３．６７％，Ｓｅ２．５６％，４．５７％，回收率为：Ａｓ９８．０％－１１０．     

卡尔曼滤波分光光度法同时测定水中微量砷和磷

研究了砷钼酸和磷钼酸与乙基罗丹明Ｂ的缔合物的吸收光谱，并以卡尔曼滤波算法对这两个严重重叠的光谱进行数据解析，达到了不需分离和掩蔽而同时测定砷和磷的目的，本法准确，精密，应用于水样分析，获得满意结果。     

石墨炉原子吸收光谱法测定生活饮用水中砷的方法优化

建立了石墨炉原子吸收光谱(GFAAS)法测定生活饮用水中砷的方法。升压放电空心阴极灯的使用,降低了基线噪声水平和检出限。对温度程序、化学基体改进剂和热稳定剂进行了优化并用于GFAAS测定砷,无需进行初步处理。研究结果显示,线性方程为y=0.005 62x+0.000 04,相关系数R为0.998 3,样品体积为16μL时的检出限为0.26μg/L。加标回收率为98.1%～99.2%,相对标准偏差<5%。取实际饮用水样验证了其适用性。     

离子色谱法测定选矿废水中4种阴离子

采用离子色谱法测定选矿废水中微量F-、Cl-、NO3-、SO42-的含量。以SH-AC-1型阴离子分离柱为离子交换柱,以2.5 mmol.L-1碳酸钠-3.5 mmol.L-1碳酸氢钠溶液为淋洗液,采用抑制电导器检测。F-、Cl-、NO3-、SO24-4种阴离子分别在0.01~4.0,0.01~15.0,0.01~15.0,0.01~30.0 mg.L-1范围内呈线性关系,检出限(3S/N)分别为6.13,3.89,5.86,8.49μg.L-1。方法用于选矿废水试样中4种阴离子的测定,加标回收率分别为97.5%,104.0%,102.0%,98.3%,相对标准偏差均小于4.0%。     

石墨炉原子吸收光谱法测定生活饮用水中砷的方法优化

建立了石墨炉原子吸收光谱(GFAAS)法测定生活饮用水中砷的方法。升压放电空心阴极灯的使用,降低了基线噪声水平和检出限。对温度程序、化学基体改进剂和热稳定剂进行了优化并用于GFAAS测定砷,无需进行初步处理。研究结果显示,线性方程为y=0.005 62x+0.000 04,相关系数R为0.998 3,样品体积为16μL时的检出限为0.26μg/L。加标回收率为98.1%～99.2%,相对标准偏差5%。取实际饮用水样验证了其适用性。     

Determination of Trace Arsenic and Selenium in Water Samples by Inductively-Coupled-Plasma Mass Spectrometry

Utilisation of a miniature anion-exchanger preconcentration column of Dowex 1-X8 to increase the sensitivity for As and Se determinations by inductively-coupled-plasma mass spectrometry (ICP-MS) is described. The ion signal was enhanced were 15 fold for As and 20 fold for Se. The multielement detection limits were 2 ppt (ng/L) and 33 ppt for As and Se, respectively. This flow injection ICP-MS method was applied to the determination of trace levels of arsenic and selenium in riverine reference material SLRS-2 and spring water samples.     

全自动电位滴定法测定水中氯化物

为了实现快速准确测定水中氯化物含量,建立了一种全自动电位滴定法测定水中氯化物的分析方法,对取样体积进行了优化,结果表明本方法最佳取样体积为50mL。研究了CO32-、S2-、I-、Br-等对氯化物测定结果的影响,并就干扰离子的消除提出了有效的方法,水样中加入1 ml （2+98）硝酸溶液可消除S2-、CO32-的干扰,当水样中I-、Br-浓度高于5mg/L时仪器可自动校正并扣除干扰。本方法检出限为0.19mg/L,大大低于水质 氯化物的测定 硝酸银滴定法GB 11896-89中规定的10 mg/L的要求,该方法测定地表水、地下水和工业废水实际样品,精密度为1.9%～2.3%,加标回收率为91.9%～99.0%。采用全自动电位滴定法测定水中氯化物,方法检出限低、精密度和正确度良好。本方法的建立为复杂环境水样中氯化物的准确测定提供了有益的技术支撑。     

高效毛细管电泳法测定人血及尿样中甲磺酸帕珠沙星

采用高效毛细管电泳法测定甲磺酸帕珠沙星在人血及尿样中的含量。实验用未涂层弹性石英毛细管柱,规格是39 cm×50μm(i.d.),其有效长度为28.5 cm。pH 6.0的磷酸盐缓冲溶液(75 mmol/L)作为运行缓冲液,氧氟沙星为内标,在10 kV高压下进样12 s,分离电压选择20 kV,在波长为247 nm的条件下,可有效分离甲磺酸帕珠沙星与氧氟沙星。甲磺酸帕珠沙星在10~700μg/L质量浓度范围内线性良好(r=0.999 6),检出限为5.0μg/L。此方法简便、准确、重复性好。     

Optimisation and critical evaluation of a collision cell technology ICP-MS system for the determination of arsenic in foodstuffs of animal origin

The determination of arsenic (⁷⁵As) was studied using an ICP-MS equipped with collision cell technology (CCT). Different mixtures of gases (He and H₂) were tested using HCl conditions and a He flow rate of 4 mL min⁻¹ was found to be suitable for the removal of the poly-atomic spectral interference [⁴⁰Ar³⁵Cl]⁺. Trueness of the optimised method has been evaluated in both standard and CCT modes on six certified reference materials in foodstuffs of animal origin and on three external proficiency testing schemes (FAPAS). The results obtained generally coincided with the certified values, except for CCT mode in some categories of samples (meat, mussels and milk powder), for which a positive bias on results was observed due to the formation of poly-atomic interferences within the collision cell. The main interferences were studied and their contributions estimated. [⁵⁸Fe¹⁶O¹H]⁺ and [⁷⁴Ge¹H]⁺ were the most significant interferences formed in the cell. Finally, different parameters (e.g. hexapole and quadrupole bias voltage, nebuliser gas flow) were optimised to try to attenuate these interferences.     

Capillary Electrophoresis Coupled with Electrochemiluminescence for the Facile Separation and Determination of Salbutamol and Clenbuterol in Urine

A capillary electrophoresis coupled with tris(2,2′‐bipyridyl) ruthenium(II) (Ru(bpy)₃²⁺) electrochemiluminescence detection system was developed to determine salbutamol and clenbuterol in urine. Some factors that affected the performances of separation and detection were investigated. Under the optimized conditions, one single quantitative analysis of salbutamol and clenbuterol was achieved at a separation voltage of 15 kV within 9 min, and the LODs (S/N=3) and LOQs (S/N=10) of salbutamol and clenbuterol were 8.43×10^?8 mol/L, 2.61×10^?7 mol/L and 2.73×10^?7 mol/L, 8.21×10^?7 mol/L, respectively. The recovery obtained from the analysis of spiked urine samples was between 88.6 % and 104.7 % with RSDs lower than 6.70 %. The method was successfully applied to determine salbutamol and clenbuterol in urine samples.     

离子色谱／氢化物发生／原子吸收法测定天然水中的砷形态

砷酸盐(As(Ⅴ))、亚砷酸盐(As(Ⅲ))、甲基胂酸盐(MMAA)和二甲基胂酸盐(DMAA),是天然水中砷的主要存在形态。本文用离子色谱分离这些砷形态,继以KBH_4还原、原子吸收法检测。分离用国产YSA-Ⅱ型阴离子交换色谱柱来完成。按上述砷形态的顺序,检出限以砷计是0.8μl、0.2μl、0.4μl和0.4μg/L。湖水样及市售矿泉水样的加标回收率为93.2％～107.5％。给出上述水样中砷形态的分析结果。     

双硫腙光极法测定废水中的痕量汞离子

本文用双硫腙为探针制备了PVC膜离子选择性光极,在优化膜组成和考察对常见金属离子响应的基础上,提出了一种测定痕量汞的光极方法。结果表明:光极膜组成为双硫腙∶PVC∶DOP∶KTpClPB(相对于双硫腙的mol%)=4∶60∶120∶50%时,对汞离子的响应最佳;在pH4.5的缓冲体系中,该光极对5×10-8～7×10-7mol/L的Hg2+有线性响应,检出限达4×10-8mol/L,只有Ag+、Pb2+有较小干扰,可用于水体中痕量汞的快速检出。     

聚四氟乙烯毛细管在线富集分离痕量钌(Ⅲ)及荧光测定

利用碱性条件下聚四氟乙烯毛细管(PTFEtube)对钌-邻菲罗啉具有富集作用,建立了单道流动注射在线富集分离及检测痕量钌的荧光分析法。本方法考察了毛细管壁、流速、pH值、温度及掩蔽剂EDTA、干扰离子等因素对富集效果的影响。当浓缩液pH值为11.8,邻菲罗啉浓度为1×10-4mol/L,浓缩和洗脱速度为3.8mL/min及EDTA的浓度为2×10-2mol/L时,获得最佳结果。在优化的实验条件下,该方法在0~50ng/L范围内呈良好的线性关系,检出限为0.8ng/L(S/N=3);RSD=2.1%(n=3)。     

毛细滴管称量滴定法测定水中溶解氧

将微量称量滴定法应用于硫代硫酸钠-碘量法测定水中溶解氧的含量.在滴定中采用自制的聚乙烯毛细滴定管代替了国标GB 10738-1989中所规定使用的结构复杂精细的称量滴定装置.操作时,在聚乙烯毛细滴定管中吸满了Na2S2O3标准溶液,在精密电子天平上称得滴定前后(以淀粉为指示剂)毛细滴定管及滴定剂的总质量.从滴定中所耗Na2S2O3标准溶液的质量按文中所给出的公式即可计算水样中的溶解氧含量,所制作的毛细管滴定管每滴滴定剂的质量要求控制在0.005～0.010 g之间,滴定过程的相对偏差可控制在1.0%左右.由于滴定系在微量水平上进行,因此方法具有消耗试剂少,操作快速而方便,且能取得优于国标方法的准确度和精密度,对4个水样进行分析,测得结果的相对标准偏差值(n=7)在0.18%～0.66%之间,明显小于国标方法测定结果的相对标准偏差(0.43%～1.26%).     

Determination of Arsenic in Beverages and Foods by Hydride Generation Atomic Absorption Spectroscopy

Abstract

The determination of the arsenic content of foods and beverages by a technique involving a magnesium nitrate aided dry ashing step followed by an arsine generation atomic absorption finish is described. Recoveries of various arsenic species added prior to ashing was excellent. Total arsenic concentrations found in samples of beverages ranged from less than 10 to 265 ppb and in foods from 20 to 9290 ppb. The sensitivity of the technique is approximately ten-fold better than obtainable with commercially available hydride generation atomic absorption units.     

流动注射-氢化物发生-电感耦合等离子体原子发射光谱法测定铜合金中痕量砷

本文研究了732强酸性阳离子交换树脂对铜离子的交换条件,并与流动注射(FⅠ)相结合,建立了一种新型高效的在线FⅠ-阳离子交换-氢化物发生-ICP-AES分析体系。本法经离子交换柱可消除高达10mg/ml铜离子的干扰,同时可以使分析速度和灵敏度大大提高。每小时可分析25个样品,砷的检出限为0.9μg/g。     

中毒患者血清和尿液中毒鼠强残留物的GC-MS分析方法

有关资料表明,人和动物口服毒鼠强后,其血液、尿液和各脏器中均有毒鼠强残留物出现,残留时间从药后数小时至几天乃至十几天之内不等。可见血液和尿液作为可印证中毒病人中毒原因的直接样品更值得我们去关注,与呕吐物、可疑食物等检品相比,它具有提取相对简单,干扰成分少,残留时间长以及可反复采集等许多优点。因此,我们结合突发性中毒检验工作的需要,利用超声波液-液萃取技术,研究了中毒患者血清和尿液中毒鼠强残留物的GC-MS-SIM检测方法。在对40多人份血清和尿液添加标准物的反复测定中,回收率血清保持在90.8％～99.5％;RSD为3.82％,尿液保持在91.2％～102.8％,RSD为4.91％,全过程仅需约30min。经过两年来百多份样品检测的验证,该方法不失为日常快速分析中毒患者血清和尿液中毒鼠强残留物的一种有效方法,现介绍如下。     

Redox Speciation of Inorganic Arsenic in Water and Saline Samples by Adsorptive Cathodic Stripping Voltammetry in the Presence of Sodium Diethyl Dithiocarbamate

This paper describes a new voltammetric procedure for the inorganic speciation of As(III) and As(V) in water samples. The procedure is based on the chemical reduction of arsenate [As(V)] to arsenite [As(III)] followed by the voltammetric determination of total arsenic as As(III) at the hanging mercury drop electrode (HMDE) by adsorptive cathodic stripping voltammetry (AdCSV) in the presence of sodium diethyl dithiocarbamate (SDDC). The reduction step involved the reaction with a mixture of Na₂S₂O₅ and Na₂S₂O₃ in the concentrations 2.5 and 0.5 mg mL^?1, respectively, and the sample heating at 80 °C for 45 min. The linear range for the determination of total arsenic as As(III) in the presence of SDDC was between 5 and 150 μg L^?1 for a deposition time of 60 s (r=0.992). A detection limit of 1.05 μg L^?1 for total As was calculated for the method in water samples using a deposition time of 60 s. The detection limits of 4.2 μg L^?1 and 15.0 μg L^?1 for total As in seawater and dialysis concentrates, respectively, were calculated using a deposition time of 60 s. The relative standard deviations calculated were 2.5 and 4.0% for five measurements of 20 μg L^?1 As(V) as As(III) in water and dialysis concentrates, respectively, after chemical reduction under optimized conditions. The method was applied for the determination of As(III) and total As in samples of dialysis water, mineral water, seawater and dialysis concentrates. Recovery values between 86.0 and 104.0% for As(III) and As(V) added to the samples prove the satisfactory accuracy and applicability of the procedure for the arsenic monitoring.