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1.
微波消解-氢化物发生-原子荧光光谱法测定7种中草药中砷   总被引:2,自引:0,他引:2  
利用原子荧光光谱法测定7种驱虫类中草药中的砷.实验采用微波消解样品,以盐酸为测定介质,硫脲-抗坏血酸为预还原剂,硼氢化钾为氢化剂,用氢化物发生-原子荧光光谱法测定砷含量.砷含量在10-100ng/mL浓度范围内线性关系好(r2=0.9924).回收率为93.83%-110.94%之间.方法简便、快速、灵敏、准确,可用于中草药中砷的测定.  相似文献   
2.
微波消解ICP-AES法同时测定花岗石中铜、镉、铬和砷   总被引:9,自引:3,他引:6  
张萍 《光谱实验室》2002,19(3):338-340
本文采用微波消解和ICP-AES法,同时测定花岗石样品的铅、镉、铬、砷4有害元素,检出限分别为0.0008、0.0007、0.0018、0.0012μg.mL^-1,回收率为93.4%-102.5%,RSD为1.3%-3.6%,该法准确、快速、简便,结果令人满意。  相似文献   
3.
一次消解测定蔬菜中多种重金属的简捷方法   总被引:1,自引:0,他引:1  
针对一般实验室检测人员少,检测任务重的问题,研究了蔬菜通过一次湿化消解后,消解液可以测定多种重金属元素的方法,大大提高了效率,减轻了工作量.  相似文献   
4.
本文阐述了用H3PO4、HF、HNO3及HClO4消化土壤及水系沉积物样品。其中磷酸的作用是避免在样品消化过程中硼的挥发损失。应用电感耦合等离子体发射光谱(简称ICP-AES)同时测定样品中全硼及其它微量、常量元素的含量。该法具有高的准确度及精密度。方法快速、简便、适合土壤和沉积物的多元素测定。  相似文献   
5.
用DSC研究纯三水铝石溶出动力学   总被引:1,自引:0,他引:1  
在DSC上研究了NaOH溶液中合成三水铝石的溶出过程动力学。应用非等温反应动力学模型计算了动力学参数,分析和确定了反应机理。模型计算结果与用DSC测得的结果吻合。  相似文献   
6.
Four analytical approaches, based on different physical principles, for the determination of antimony (Sb) and arsenic (As) in ancient peat samples were critically evaluated: (a) open vessel digestion/hydride generation-atomic absorption spectrometry (HG-AAS), (b) closed-pressurized digestion in a microwave oven followed by sector field-inductively coupled plasma-mass spectrometry (SF-ICP-MS), (c) digestion in a microwave autoclave and subsequent quadrupole-inductively coupled plasma-mass spectrometry (Q-ICP-MS) measurements and (d) instrumental neutron activation analysis (INAA). The quality control scheme applied, always included the use of adequate plant reference materials to ensure the accuracy and precision of the analytical procedures. Additionally, two internal peat reference materials were analyzed using all four analytical approaches, generally showing good agreement for both elements. Method detection limits for As and Sb provided by all procedures were approximately 5 and 2 ng g−1 which is sufficiently low for the reliable quantification of both elements in ancient, pre-anthropogenic peat samples. A comparison of As and Sb concentrations in a set of peat samples determined by INAA, HG-AAS and SF-ICP-MS revealed that INAA underestimated the values in a systematic manner, whereas HG-AAS and SF-ICP-MS data agreed very well. Best precision of the results was obtained by analytical procedures involving HG-AAS or Q-ICP-MS and varied from 3.6 to 4.3% and 7.1 to 7.5% for As (at about 0.5 μg g−1) and Sb (at about 0.1 μg g−1), respectively. The highest sample throughput (40 samples per run accomplished in 2 h) combined with low risk of sample contamination could be realized in the high-pressure microwave autoclave. The amount of sample required by all approaches was 200 mg, except for INAA which needed at least 25 times more sample mass to achieve comparable detection limits. For the quantification of As and Sb, inductively coupled plasma-mass spectrometry (ICP-MS) was preferred over INAA and HG-AAS, mainly because (a) less sample is needed and (b) As and Sb can be determined simultaneously. In addition, ICP-MS offers the possibility to measure concurrently a wide range of other elements which also are of environmental interest.  相似文献   
7.
G. Doner  A. Ege 《Analytica chimica acta》2004,520(1-2):217-222
An evaluation is made of different digestion methods for the determination of iron and zinc in biscuits prior to flame atomic absorption analysis. For the initial studies, microwave digestion was enough (using hydrogen chloride and nitric acid 3:1, v/v, at 180 °C and 600 W) to provide comparable accuracy, precision, digestion time and non-critical handling of reagents to dry-ashing and wet digestion (using different acid mixtures) and also to a simple acid treatment at room temperature. Although, after a simple microwave digestion, the spiked recoveries were found around 96–102%, to reduce the digestion time and for simplicity we worked on wet acid treatments. The results showed that acid-only treatment is not enough to digest the samples without adding ethanol, which was found necessary to digest organic residue at room temperature. The method was validated by comparison of the data found for commercial biscuit samples through using the proposed procedure and the AOAC official reference spectrophotometric method. Fe concentration in the different biscuits (such as petit beurre, baby biscuits, etc.) ranged from 1.21 to 15.96 mg/100 g while Zn concentration ranged from 0.58 to 2.50 mg/100 g depending on biscuit type. The highest concentration of Fe was in baby biscuits and these biscuits were about thirteen times richer in Fe than petit beurre biscuits.  相似文献   
8.
微波消解石墨炉原子吸收光谱法测定水产品中镉   总被引:3,自引:1,他引:2  
采用微波消解样品,石墨炉原子吸收光谱法测定水产品中镉。在最佳试验条件下,镉的线性范围为0—2μg·L-1,检出限为1.3pg。相对标准偏差为1.9%—3.1%,本方法简便,快速、准确。  相似文献   
9.
微波消解FAAS测定新疆出口番茄酱中的微量元素   总被引:2,自引:0,他引:2  
陈兆慧  解成喜  张旭龙 《光谱实验室》2007,24(1):I0042-I0044
采用微波消解试样,FAAS法对新疆4个厂家出口番茄酱中的微量元素进行测定.经过回收率和精密度试验,结果表明:6种微量元素的相对标准偏差在0.23%-2.10%;回收率在94.8%-104.5%;并以番茄叶的标准样品(ESP-1)进行比较测定,标准样品的测定值与参考值基本一致,该方法获得了满意的精密度和准确度.  相似文献   
10.
微波消解-原子吸收光谱法测定桑叶中微量元素   总被引:4,自引:0,他引:4  
用微波消解及火焰原子吸收法测定5月,6月,8月,9月及10月等5个时期的桑叶中Fe,Mn,Cu,Zn,Ca 5种元素的含量,同时做精密度和加标回收试验,并对其含量进行比较,以期为临床,药物及食用含量研究开发利用提供参考.测定结果表明,各元素总体含量Ca>Fe>Mn>Zn>Cu,不同时期桑叶中微量元素各不相同,9月的桑叶中,各元素的含量均较高.  相似文献   
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