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1.
针对常规化学形态分析方法对浸取剂高选择性要求及严重串相问题等缺点,在浸取常数稳定的前提下,以常规化学形态分析方法为基础,确定了建立标准样本的方法,将系统聚类法用于模拟地质样品中各形态铅的同时测定。克服了串相问题及降低了对浸取剂高选择性的要求,用此法对模拟样品进行了分析,相对误差小于±11%,结果优于常规化学形态分析方法。  相似文献   

2.
吴周安  吴清盛 《分析化学》1997,25(8):991-991
1引言乙酰水杨酸散系解热镇痛药,其有效成份为乙酰水杨酸,所含的水杨酸是杂质。卫生部标准WS-059(x-046)-95(试行)系采用甲醇-冰乙酸为溶剂浸取样品中的乙酰水杨酸和水杨酸,然后用HPLC外标法同时测定。但乙酰水杨酸在这种溶剂中易分解生成水杨酸,使水杨酸的测定结果偏高。本文在该产品的部颁标准基础上,改用乙醇-氯乙酸作溶剂,有效地抑制了乙酰水杨酸的分解,采用超声波浸取法,使待测物被完全浸取,通过内标物的采用和检测波长的选择,使测定的准确度和精密度得到显著改善。2实验部分2.1仪器及试剂日本…  相似文献   

3.
化学浸提法研究中药茯苓中活性铝的形态分布   总被引:2,自引:1,他引:1  
利用KCl、NH4Ac、HCl、NaOH四种浸提液对中药茯苓中铝的存在形态分别进行浸取溶出,采用分光光度法对不同形态的铝含量进行测定,得到茯苓中活性铝的形态分布,有机铝含量占总量的58.9%;胶态Al(OH)3占总量41.1%;浸提液中铝的回收率为97.0%~109.3%。  相似文献   

4.
电位滴定法测定铜业矿中氯   总被引:3,自引:1,他引:3  
提出了用氧化锌-无水碳酸钠混合熔剂与铜精矿样品在高温焙烧,分离大量的基体元素,用沸水浸取烧结物,在丙酮-水混合溶剂中用硝酸银电位滴定测定其中的氯总量,方法重现性好,适应性好,可准确测定铜精矿中的氯。  相似文献   

5.
本文研究了饱和硫化钠溶液对土壤样品中硫化汞的浸取效率(其加标回收率达100%),以及用硝酸和硫化钠溶液对样品中汞的选择性浸取并研究了土壤中硫化汞垂直分布。提出了利用硝酸、饱和硫化钠溶液浸取,由冷原子荧光法选择性测定土壤及河流沉积物中硫化汞的新方法。用该方法对同一样品进行8次测定,其相对标准偏差为7.1%。  相似文献   

6.
植物中砷的形态分析   总被引:14,自引:0,他引:14  
应用离子交换树脂静态吸附和溶剂萃取相结合的分离技术,分析了植物中砷的四种形态化合物:无机三价砷和五价砷,一甲基胂和二甲基胂。并用石墨炉原子吸收光谱法(GFAAS)测定其含量。文中采用HCl浸提植物的砷,并对HCl的浓度、体积以及浸提时间作了详细的探讨。用20mL1mol/LHCl对1.0g干植物2d的浸出量与传统消化法总量的比值为0.85-1.00。对浸出液进行形态分析,总砷回收率为86%-93%  相似文献   

7.
原子吸收法直接测定食用L-赖氨酸盐酸盐中的锌和铁   总被引:3,自引:0,他引:3  
陕方  边俊生 《分析化学》2002,30(2):251-251
1 引 言作为食品营养强化剂,L-赖氨酸盐酸盐越来越受到人们的青睐。据报道,目前在国际上氨基酸工业中,除谷氨酸外,生产最多的是L-赖氨酸。产品的质量与人体健康密切相关,Zn和Fe的含量是L-赖氨酸产品质量的重要指标,我们选择石墨炉-原子吸收法对这两种元素进行了测定。样品的预处理,诸如湿法消解、干法灰化、萃取等,易引起待测成分的逸失或干扰测定结果,使操作繁琐,分析时间延长。本实验将样品用稀酸溶解,直接注入石墨炉进行Zn和Fe的测定。操作简便、快速,缩短了分析周期。2 实验部分2.且 仪骼与试剂 仪器:AA…  相似文献   

8.
介绍了用平台石墨炉原子吸收法测定血清铬的方法,详述了测定的实验条件,比较了平台石墨炉原子吸收法与火焰法、普通石墨管石墨炉原子吸收法测定血清铬的差异,提出以硝酸镁为基体改进剂,血清经酸处理后可使测定结果几乎无干扰,并测定75名健康体检者,其参考范围为0.476-0.592μg/L。  相似文献   

9.
石墨炉原子吸收法测定植物样品中硼的研究   总被引:2,自引:0,他引:2  
本文比较了四种石墨和三种基体改进剂对石墨炉法测硼的影响。结果表明,使用涂层石墨管并采用Ca-Mg-抗坏血酸作基体改进剂,可获得最高的灵敏度和最好的回收率,讨论了硼的最佳工作条件和干扰情况,对植物标准样品进行了测定,所得结果与标准值吻合,植物中硼含量为34~53μg/g时,方法的相对标准偏差为2.1%~3.8%,检出限为378pg(K=3)。  相似文献   

10.
探针技术石墨炉原子吸收光谱测定人发中痕量铅   总被引:1,自引:0,他引:1  
周立群  蔡火操 《应用化学》1997,14(4):99-101
探针技术石墨炉原子吸收光谱测定人发中痕量铅周立群*蔡火操葛伊莉张必成(湖北大学实验中心武汉430062)(湖北大学化学系武汉)关键词石墨探针,石墨炉原子吸收光谱,痕量铅,人发1996-10-16收稿,1997-04-22修回大量研究表明,人体很多疾病...  相似文献   

11.
火焰原子吸收光谱法分析沉积物中重金属元素的形态   总被引:1,自引:0,他引:1  
采用原子吸收光谱法研究了金沙江攀枝花段水系沉积物中重金属的形态及分布特征。研究发现,各重金属的形态以残渣态为主,离子交换态含量很少。同时说明原子吸收光谱法完全可以用来研究重金属形态特征,在环境研究中具有重要意义。  相似文献   

12.
本实验对含13味中药的治肺癌复方原药,头煎及二煎残渣和浸汁,经0.45μ膜分离的颗粒物,可溶态,以及可溶态分别通过阳离子交换树脂,用三氯甲烷萃取后所得各自柱截留物,穿过物,有机相,水相等共15个样品中铬,镍,按照中药微量元素初级和次形态分析的要求,进行分析测定,以此计算出一套形态分析参数和相关数据,为探讨中草约中微量元素的化学形态提供了新的信息。  相似文献   

13.
用原子吸收光谱法,对产于青藏高原的藏草药水母雪兔子和多刺绿绒蒿,测定了全药材、水提液、醇提液中12种元素(Cr、Cu、Fe、Mn、Ni、Se、Zn、K、Ca、Mg、Cd、Pb)的含量,以及水提液中各元素可溶态、水溶态的含量,同时采取正辛醇-水分配体系模拟藏药水提液中各微量元素在人体胃肠中的分配情况,对藏药中微量元素的初级形态进行了分析,初步探讨了酸度变化(人体胃肠酸度)对微量元素的影响,结合藏药药效讨论其相关性,为进一步研究微量元素与藏药药性、药效的关系提供科学依据.  相似文献   

14.
原子吸收法对藏草药川木香中12种元素的初级形态分析   总被引:2,自引:0,他引:2  
用原子吸收分光光度法,测定了产于青藏高原的藏草药川木香的全药材、水提液、醇提液中12种元素(Cr、Cu、Fe、Mn、Ni、Se、Zn、K、Ca、Mg、Cd、Pb)的含量,以及水提液中各元素可溶态、水溶态的含量,同时采取正辛醇-水分配体系模拟藏药水提液中各微量元素在人体胃肠中的分配情况,对藏药中微量元素的初级形态进行了分析,初步探讨了酸度变化(人体胃肠酸度)对微量元素的影响,结合藏药药效讨论其相关性,为进一步研究微量元素与藏药药性、药效的关系提供科学的依据和奠定基础.  相似文献   

15.
Because atomic absorption spectrometry (AAS) seems to be so simple at first glance, its forthcoming end and replacement by more exciting techniques has been forecasted more than once over the past 45 years. However, AAS has received strong impetus again and again, e.g. by the introduction of the graphite furnace technique, and of flow injection, to mention but a few. Although more and more researchers, and even more instrument manufacturers are turning their back on AAS these days, this author believes that AAS is about to give birth to new offspring in the very near future. The most important ones are solid sampling and speciation analysis on the application side, a much deeper exploitation of the potential of flow injection analysis, the use of diode lasers as radiation sources, and the introduction of continuum-source AAS on the instrumental side. The latter could replace conventional line-source AAS in the foreseeable future because of its obvious advantages in essentially all analytical aspects.  相似文献   

16.
石墨炉原子吸收光谱法直接测定尿中痕量锰   总被引:6,自引:0,他引:6  
应用硝酸作基体改进剂 ,石墨炉原子吸收光谱法直接测定尿中痕量锰。方法简便、快速、准确 ,灵敏度高。方法的检出限为 0 .0 80 μg·L- 1,回收率为 97.2 %。对锰含量为 5 μg·L- 1的尿样测定 7次的相对标准偏差为 3.16%  相似文献   

17.
Speciation of lead in soils and relation with its concentration in fruits   总被引:4,自引:0,他引:4  
The lead concentrations of the fruit samples were determined by using slotted tube atom trap (STAT)-enrichment-flame and graphite furnace atomic absorption spectrometry (FAAS and GF-AAS). The soil samples related to these fruits were also analysed for Pb after extraction with various chemical reagents. The relation between the fruit-lead and soil-extractable lead concentrations was examined in order to explain the bioavailability of lead. A linear relation was observed between the hot Na2EDTA extraction-soluble Pb contents in the soil and the Pb concentrations in the mulberry (R2=0.95), strawberry and apple grown on these soils. Probable chemical forms of lead in soil were evaluated. Acceptable agreement (at least 91%) was achieved between the results of STAT-enrichment-FAAS and GF-AAS.  相似文献   

18.
石墨炉原子吸收法测定红细胞锰   总被引:1,自引:0,他引:1  
以1%Triton X-100溶液稀红细胞成悬液,用日立180-80型塞曼原子吸收分光光度计石墨炉原子化法测定其中的锰含量、由工作曲线校准,回收率在97.0%-104.0%,重现性变异系数〈5.0%。  相似文献   

19.
A rapid, sensitive and selective method is described for the determination of chromium(VI) in presence of 100-fold amounts of chromium(III) by flame atomic absorption spectrometry (FAAS) in conjunction with coprecipitative preconcentration of its ethyl xanthate complex onto naphthalene. The solid mixture consisting of the chromium(VI) complex together with naphthalene is dissolved in 8.0 ml of dimethyl formamide (DMF) and chromium(VI) content was established by FAAS. Calibration graphs were rectilinear over the chromium(VI) concentration in the range 0-200 μg l−1. Five replicate determinations of 20 μg of chromium(VI) present in 1.0 l of sample solution gave a relative standard deviation of 3.1%. The detection limit corresponding to three times the standard deviation of the blank was found to be 0.5 μg l−1. The developed procedure has been successfully utilized for the estimation of chromium(VI), chromium(total) (after oxidation with bromate) and chromium(III) (by subtracting chromium(VI) content from chromium(total) value contents of several tannery industries.  相似文献   

20.
Increasing numbers of clinical laboratories are transitioning away from flame and electrothermal AAS methods to those based on ICP-MS. Still, for many laboratories, the choice of instrumentation is based upon (a) the element(s) to be determined, (b) the matrix/matrices to be analyzed, and (c) the expected concentration(s) of the analytes in the matrix. Most clinical laboratories specialize in measuring Se, Zn, Cu, and Al in serum, and/or Pb, Cd, Hg, As, and Cr in blood and/or urine, while other trace elements (e.g., Pt, Au etc.) are measured for therapeutic purposes. Quantitative measurement of elemental species is becoming more widely accepted for nutritional and/or toxicological screening purposes, and ICP-MS interfaced with separation techniques, such as liquid chromatography or capillary electrophoresis, offers the advantage of on-line species determination coupled with very low detection limits. Polyatomic interferences for some key elements such as Se, As, and Cr require instrumentation equipped with dynamic reaction cell or collision cell technologies, or might even necessitate the use of sector field ICP-MS, to assure accurate results. Nonetheless, whatever analytical method is selected for the task, careful consideration must be given both to specimen collection procedures and to the control of pre-analytical variables. Finally, all methods benefit from access to reliable certified reference materials (CRMs). While a variety of reference materials (RMs) are available for trace element measurements in clinical matrices, not all can be classified as CRMs. The major metrological organizations (e.g., NIST, IRMM, NIES) provide a limited number of clinical CRMs, however, secondary reference materials are readily available from commercial organizations and organizers of external quality assessment schemes.  相似文献   

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