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1.
目的:建立微波消解-氢化物发生-原子荧光光谱法测定中药材中痕量汞的方法。方法:用微波消解法对几种常用中药材样品进行前处理,用氢化物发生-原子荧光光谱法测定其中痕量汞。结果:微波消解过程中,消解试剂选择硝酸+双氧水,且按3∶1比例混合时消化效果最佳,汞在浓度为0μg/L~4μg/L范围内线性关系良好,相关系数r=0.9999,方法检出限为0.014μg/L,测定汞1.0μg/ml标准溶液相对标准偏差为1.99%,测定国家一级标准物质人发(GBW09101)相对标准偏差为3.37%,且测定结果与标准含量一致。结论:该方法测定中药材中的痕量汞简便快速,准确灵敏,易于推广。  相似文献   

2.
目的 探讨冷原子荧光法在测定人发汞时的工作条件。方法 发样经洗涤烘干后在管式炉内(750±50)℃燃烧5min,吸收液中的汞被SnCl2还原后于253.7 nm用冷原子荧光法测定。结果 以3g/L SnCl2为还原剂,线性范围0.04-2.0μg/L,r=0.9999,检出限为0.05μg/L,相对标准偏差为2.5%,平均回收率在90.0%~110.0%。结论 冷原子荧光法可用于人发痕量汞的测定。  相似文献   

3.
还原气化-原子吸收光谱法测定尿中汞的方法研究   总被引:2,自引:0,他引:2  
目的 研究还原气化-原子吸收光谱法分别测定尿中总汞、无机汞和有机汞的方法。尿样中汞(汞中无机汞和经溴酸钾-溴化钾处理尿中有机汞生成的无机汞)以硼氢化钠还原生成汞原子蒸气,用原子吸收分光光度仪分别测定其总汞、无机汞和有机汞的含量。结果 该法在0-48μg/L范围内,直线回归相关系数总汞和无机汞分别为0.9992、0.9990,检测限总汞为0.028μg/L、无机汞为0.025μg/L,精密度测定相对标准偏差总汞为2.5%-4.5%、无机尔为1.1%-5.1%,加标回收率总汞测定为97.83%-98.56%、无机汞测定为95.25%-96.25%。结论 该方法对尿汞测定是一种准确、灵敏、快速、简便的分析方法。  相似文献   

4.
本主要报道了用氢化物发生原子荧光法对水样中的痕量汞进行测定的方法,本法具有操作简单、快速、灵敏度高、精确度高等优点。方法的检出限为0.034μg/L以下,回收率为96%-104%,多次测定同一样品的相对标准偏差不超过2.50%。  相似文献   

5.
氢化物发生-原子荧光法同时测定尿中砷和汞   总被引:18,自引:2,他引:16  
目的:建立同时测定尿中砷和汞的氢化物发生-原子荧光法。方法:采用硝酸-高氯酸消化法。结果:砷和汞的线性检测范围分别为0-100μg/L和0-80μg/L。方法检出限分别为0.36μg/L和0.048μg/L,样品加标加收率砷为87.5%-101.0%,汞为92.0%-105.7%。结论:本法具有基体干扰小,灵敏度高、检出限低、线性范围宽、操作简便、快捷、结果准确可靠的优点,适合职业人群尿砷、汞的检测分析。  相似文献   

6.
水样中亚硝酸盐的高效液相色谱测定法   总被引:4,自引:0,他引:4  
目的:建立水样中亚硝酸盐的高效液相色谱分析方法。方法:用间接紫外-高效液相色谱法测定水样中痕量亚硝酸盐,以甲醇-0.10mol/L邻苯二甲酸(用0.10mol/L氢氧化钠调pH=8.6)5 95为流动相,采用ODP色谱柱,水样直接过滤处理法。结果:测定波长270nm,流量0.9ml/min,测定亚硝酸盐的线性范围为0.0-20.0μg/ml,精密度为3.9%,平均回收率为99.9%,检测限为0.001μg/ml,结论:本法可用于生活饮用水,纯净水及矿泉水中微量亚硝酸盐的测定。  相似文献   

7.
ICP-MS测定食品中多种金属元素   总被引:8,自引:0,他引:8  
目的:建立ICP-MS同时测定食品中多种金属元素的方法。方法:用ICP-MS对食品中Pb、As、Cu、Zn、Cd、Cr、Se、Ni、Mn、Fe等10种金属元素同时测定。结果:各元素在0.5ng/L-1.0mg/L范围内呈良好线性关系,检出限位(0.01μg/L-0.39μg/L),相对标准差为0.23%-4.59%,准确度高。结论:该方法准确、快速、灵敏,适用于食品中多种微量元素的测定。  相似文献   

8.
基于在pH6.2的缓冲溶液中,痕量汞(Ⅱ)对过氧化氢氧化对乙酰偶氨胂而使其褪色的反应的抑制作用,建立了测定痕量汞(Ⅱ)新的动力学光度法。测定汞(Ⅱ)的线性范围为0.1-12.0μg/L,检出限0.1μg/L。用于食品河虾和海鱼中汞(Ⅱ)的测定,结果满意。  相似文献   

9.
同时测定保健食品中微量铅和汞的方法研究   总被引:9,自引:3,他引:6  
目的:建立一种快速消解并同时测定保健食品中微量铅和汞的方法。方法:采用微波消解样品,氢化物发生原子吸收光谱法同时测定保健食品中的微量铅和汞。结果:方法简便、快速、准确,灵敏度高,方法检出限铅和汞分别为0.10μg/L、0.35μg/L,平均加收率铅和汞分别为94.2%、103.9%,对铅含量为10.0μg/L,汞含量为10.0μg/L的样品连续测定8次的相对标准偏差分别为2.29%、3.61%。结论:保健食品中的微量铅和汞可以用氢化物原子吸收法同时测定。  相似文献   

10.
[目的]寻求一种灵敏度高,稳定性好的测定发中汞含量的新方法。[方法]采用(3:1)硝酸高氯酸混酸作消化液,在加回流管的测砷瓶内分步消化发样,流动注射氢化物发生原子吸收测定发中汞。(结果]标准偏差小于27.1ng/g;变异系数小于5.5%;样品加标率在99.8%~100.35%之间;方法的检出限为0.69ng/ml;[结论]采用流动注射氢化物发生原子吸收测定发中汞灵敏度高,稳定性好,精密度和准确度均符合微量分析要求。  相似文献   

11.
Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.  相似文献   

12.
This paper examines media coverage of 'breast cancer genetics', and explores its implications for public understanding. We present a content analysis of coverage in British newspapers and look at a variety of popular forms, including women's magazines, television soap opera and radio drama. Genetic/inherited risk receives a great deal of coverage across a wide range of media formats and outlets. Much of this attention has focused on individuals from 'high risk families' and dilemmas around prophylactic mastectomies. Through examining media coverage, combined with interviews with media personnel and their sources, we show why this story proved so attractive to the media and highlight the different production values which influence coverage. Finally, we introduce preliminary findings from focus group discussions to demonstrate how such 'human interest' framing has engaged audience attention and influenced public understandings. The paper concludes by highlighting the implications for analysing, predicting, and engaging with, media representations of science.  相似文献   

13.
深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.  相似文献   

14.
Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO2) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO2. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO2 at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO2 gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO2 also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO2.  相似文献   

15.
Antibiotics represent one of the most important drug groups used in the management of bacterial infections in humans and animals. Due to the increasing problem of antibiotic resistance, assurance of the antibacterial effectiveness of these substances has moved into the focus of public health. The reduction in antibiotic residues in wastewater and the environment may play a decisive role in the development of increasing rates of antibiotic resistance. The present study examines the wastewater of 31 patient rooms of various German clinics for possible residues of antibiotics, as well as the wastewater of five private households as a reference.To the best of our knowledge, this study shows for the first time that in hospitals with high antibiotic consumption rates, residues of these drugs can be regularly detected in toilets, sink siphons and shower drains at concentrations ranging from 0.02?μg·L?1 to a maximum of 79?mg·L?1. After complete flushing of the wastewater siphons, antibiotics are no longer detectable, but after temporal stagnation, the concentration of the active substances in the water phases of respective siphons increases again, suggesting that antibiotics persist through the washing process in biofilms. This study demonstrates that clinical wastewater systems offer further possibilities for the optimization of antibiotic resistance surveillance.  相似文献   

16.
Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).  相似文献   

17.

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.  相似文献   

18.
19.
The risk of heat exhaustion at a deep underground metalliferous mine was assessed in relation to thermal conditions prevailing on the surface. For each day of a 1-year prospective case series of heat exhaustion, surface 24-h mean wet and dry bulb temperatures were recorded. From this data, 24-h mean wet bulb globe temperatures were derived using certain assumptions. The three surface temperature variables were significantly higher on those days on which heat exhaustion occurred, compared to those days on which it did not occur (P < 0.001). The relative risk of heat exhaustion on days when the 24-h mean wet bulb globe temperature was in the range 26.0-28.0 degrees C was 4.82 (95% confidence interval 2.12-10.96). Surface temperature data could be used at this mine to warn miners about the risk of heat exhaustion.  相似文献   

20.
Occupational health hazards in mining: an overview   总被引:1,自引:0,他引:1  
This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.  相似文献   

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