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目的检测铁铬合金菜刀遗留的金属颗粒成分,并建立可行的评价指标及方法。方法使用滤纸擦蹭菜刀制作金属遗留微小颗粒样本,应用扫描电镜-X射线能谱仪(scanning electron microscopy and energy dispersive X-ray spectrometer,SEM-EDX)的GSR颗粒分析功能检测遗留金属颗粒成分,计算遗留金属颗粒中铁、铬相对含量比。结果铁铬合金菜刀遗留金属颗粒内所含铁、铬相对含量比,在大部分菜刀间差异有统计学意义(P0.05)。结论使用GSR颗粒分析功能量化检测铁铬合金菜刀遗留金属颗粒内铁、铬相对含量比,为此类致伤工具的认定建立可行的评价方法。  相似文献   
2.
This research studied accumulation of heavy metals in soil and three plant species in E-waste dumpsite in Kalasin Province, Thailand. DNA changes in the plants were accessed by DNA fingerprinting and genomic template stability (GTS) analyses. Concentrations of the metals were in the order of Zn > Pb > Cd > Cr. The Bioconcentration Factor (BCF), Translocation Factor (TF), and Enrichment Factor (EF) values showed that Typha angustifolia was suitable for phytoremediation of Cd, Pb, and Zn. However, after the process of phytoremediation, appropriate abolishment of the heavy-metal containing plants should be taken to prevent the metals from passing along the food web. The GTS values ranged from 54.23 to 69.35%. These results suggest that heavy metals have affected the genotoxicity of plants grown in the electronic waste dumpsite.  相似文献   
3.
彝文金石述略   总被引:2,自引:0,他引:2  
彝文金石始于先秦 ,及至明清而达顶峰。分为丹书、铭文和摩崖碑刻。先秦至明初为单纯的彝文 ;明清时期基本为彝汉文合壁 ,且以墓碑为最多。彝文金石的价值 ,首先是研究彝族文字的第一手资料。其次 ,彝文金石内容的含盖面很广 ,是古代彝族的一部百科全书。第三 ,彝文金石的文化内函非常丰厚 ,是研究古代彝族生存的自然生态环境 ,物态文化 ,制度文化 ,社会心理 ,低层意识形态 ,高层意识形态等文化层次结构 ,特别是研究古代彝族的思维模式和价值取向的第一手资料。  相似文献   
4.
目的考察宣木瓜药食安全性,为其质量控制提供依据。方法采用石墨炉原子光谱法、火焰原子光谱法以及原子荧光法,检测8批宣木瓜样品中铅、镉、铜、砷和汞的含量;采用气相色谱法检测相同样品中有机氯、菊酯类和有机磷农药残留;利用免疫亲和层析柱净化-超高效液相色谱法检测自然条件下贮藏1~2年的宣木瓜样品中黄曲霉毒素含量。结果采集的8批宣木瓜样品铅、镉、铜、砷和汞含量均未超出规定限量;有机氯、有机磷和除虫菊酯类农药残留量均在检测限以下,未能被检出;贮藏的6批宣木瓜样品黄曲霉毒素B1、B2、G1和G2总量均在检测限以下,未能被检出。结论来源于主产区的宣木瓜在重金属、农药残留及黄曲霉毒素的检查项目上均合格,呈现良好的药食安全性品质。  相似文献   
5.
目的 对白鹃梅嫩叶及花序的重金属和农药残留量进行测定,为白鹃梅嫩叶及花序的进一步开发利用提供参考.方法 运用原子吸收分光光度法、原子荧光光度计法和气相色谱法测定白鹃梅嫩叶及花序中重金属和农药残留的含量.结果测得直接晒干的白鹃梅嫩叶及花序中砷、铅、铜的含量分别为0.147 1、3.399 7、0.187 4 mg/kg,...  相似文献   
6.
血液中Cr、Cd、As、Tl和Pb的电感耦合等离子体质谱分析   总被引:3,自引:1,他引:2  
目的 建立血液中Cr、Cd、As、Tl和Pb的电感耦合等离子体质谱(ICP-MS)分析方法. 方法血液采用微波消解仪进行处理,以115In元素作内标,使用ICP-MS方法对血液中Cr、Cd、As、Tl和Pb进行分析.结果 方法检出限为0.00001~0.00249μg/L,准确度为90.1%~110.7%,精密度为4.0%~7.9%. 结论建立的方法准确、快速、线性范围宽、灵敏度高,适用于Cr、Cd、As、Tl和Pb中毒案件的检测.  相似文献   
7.
Levels of magnesium, potassium, sodium and calcium in post-mortem vitreous humour from human controls, fire fatalities and drowning victims have been determined. The effects of time-related internal changes, external environmental parameters and different causes of death are evaluated. Despite the positive correlation and marked increase of potassium and, to a lesser extent, of magnesium and calcium with the length of the post-mortem interval, individual biological variability severely limits the usefulness of predictions of post-mortem interval based on electrolyte metal data. At best, there is only a 2/3 chance of a prediction being within 12 h of the true value. Vitreous humour metal concentrations are affected by external influences, such as the elevated temperatures of fires which increase the rate of release of intracellular magnesium and potassium. In cases where drowning is suspected, establishment or exclusion of this cause of death is not possible on the basis of vitreous humour electrolyte metal data because of possible post-immersion diffusion across the permeable membrane of the eyeball. It appears, however, that magnesium in salt-water cases and sodium in fresh-water cases are related, albeit erratically, to the length of the immersion period.  相似文献   
8.
In early 1990 s some organized criminal groups started to develop a new field of illegal business, which involved thefts of intermediary products from mining and metal-producing plants in Russia and in the south of Africa. Since local sulfide copper/nickel ores contain certain concentrations of precious and platinum group metals (PGMs), the intermediary products recovered at different stages of metallurgical transformation of these ores are materials of high commercial value. Illicit transportation and refining of these materials in Western Europe and North America has evolved into a large-scale business, where a lot of unlawful revenues are being laundered. The most important tasks in combating this organized crime are as follows: to establish the facts when some PGM-containing semi-products had been received at certain refineries; to carry out the identification of these semi-products; and to prove that these semi-products had been produced by a certain company. As a rule, it is not difficult to establish the identity of a "clean product". However, when a material is a mix of several semi-products or a mix of some semi-product with masking substances, the identification of individual components becomes an extremely complicated task. The purpose of developing the "complex procedure for establishing the nature and source of origin of precious metal-bearing products of mining and metallurgical operations" was to make possible the identification of complex mixes comprised of various metallurgical semi-products. In the complex procedure that we have developed to characterize dispersed materials, distribution of particles by their elemental composition (the so-called "pseudophase" composition) was used instead of mineralogical composition. To determine the "pseudophase" composition by the method of scanning electron microscopy with X-ray spectral microanalysis (SEM-EDX), a representative sample of material containing not less than 1000 particles was analyzed. All microparticles can be divided into several types. Each type is characterized by an association of chemical elements contained. The first stage includes the study of elemental composition by inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass-spectrometry; and the study of phase composition by X-ray diffractometry. The results of each study are compared with data in the Data Base. In case of coincidence with one of the products with respect to all diagnostic features, the type of product and its source of origin are defined accordingly. If the features of the sample under analysis detected by the aforementioned methods do not coincide with any of the product types represented in Data Base, it is necessary to examine elemental composition and morphology of separate particle contained in the substance using SEM-EDX. If some particles characterized by features coinciding with features of particles belonging to any product or products from Data Base are found, this product or a mixture of products is assumed to be present in the composition of the substance under analysis. The assumption that the substance is a mixture can be verified by juxtaposing all previously determined features of the analyzed sample with the features of the pattern mixture (superposition) of the appropriate types of products represented in Data Base. Depending on the results of this verification the corresponding conclusion can be made.  相似文献   
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