鱼塘水中常见有机磷农药的测定

<正>建立鱼塘水萃取和分析有机磷农药的方法，用于鱼塘水、井水、地面水、地下水及工业废水中的有机磷农药测定。 1 试剂与仪器 1．1 试剂 标准品 甲胺磷、DDV、氧乐果、甲拌磷、乐果、二嗪农、久效磷、杀螟松、马拉硫磷、倍硫磷、对硫磷、杀朴磷、乙硫磷。以上标准由公安部物证中心提供。分     

GC／MS分析鱼塘水中的五氯酚

目的介绍GC/MS分析鱼塘水中五氯酚的方法。方法将约500ml鱼塘水调至pH=3,用约50ml苯萃取、无水硫酸钠干燥过滤、浓缩至约0.2ml,然后再利用GC/MS联用仪分析。结果用该方法检验出四氯苯酚和五氯苯酚。结论这种方法可用来对鱼塘投毒案件中的水样进行五氯酚的检验。     

分子印迹固相萃取技术-液相色谱法测定鱼塘水中2甲4氯苯氧乙酸

目的建立分子印迹固相萃取技术对鱼塘水中2甲4氯苯氧乙酸进行提取和分析的方法。方法以2甲4氯分子印迹聚合物为固相萃取材料,对鱼塘水中2甲4氯进行分离提取,洗脱液直接进行液相色谱分析。结果鱼塘水中MCPA的提取率在80%以上,检出限0.040μg/mL,在0.2μg/mL～2.0μg/mL范围内线性关系良好。结论该方法的准确度和精密度较好,适合实际发生案件的检测分析。     

GC/MS法快速分析鱼塘水中的硫丹

目的建立一种快速、高效、便捷、绿色的分析方法来分析鱼塘水中的硫丹。方法在该实验中采用分散液液微萃取的方法来提取鱼塘水中的硫丹,该方法是一个新型的预处理方法,首先将最合适的分散剂和萃取剂快速的注射到样品溶液中,随即形成了悬浊液。由于在悬浊液中萃取剂能迅速的分散到样品溶液中并与被分析物充分接触,被分析物能很快的从样品溶液中转移到萃取剂中完成萃取过程,经过离心后,沉积物直接用GC-MS进行分析。同时还对本方法中分散剂和萃取剂种类、用量以及萃取时间等重要的实验参数进行考察优化。结果在优化的实验条件下,鱼塘水中硫丹的回收率基本能达到90%以上,检出限为0.005μg/m L,定量限为0.017μg/m L,在0.02~0.20μg/m L的z范围内线性关系良好。结论该方法的准确度和精密度较好,操作简便、快捷、绿色环保,能够基本适合鱼塘投毒案件中硫丹的分析检测。     

鱼塘水中六氯苯水解产物的检测

<正> 六氯苯(hexachlorobenzene,HCB),也称多氯苯,是一种常见的除草剂。鱼类对六氯苯的毒性比较敏感,常见于鱼塘水中毒鱼案中。本文作者采用固相萃取技术(SPE),分离富集鱼塘水中六氯苯的代谢产物——五氯苯酚,选用GC/MS技术进行分析,检出鱼塘水中的五氯苯酚。使用SPE技术分析检材中的五氯苯酚,具有快速、方便、省溶剂等优点,是一种具有潜力的实用的检验方法。     

鱼塘中投放硫丹致鱼死亡1例

1案例资料某年9月，某村村民李某养殖的60余亩鱼塘内被人投毒，致大量鱼死亡，给受害人带来巨大经济损失。后经侦查将犯罪嫌疑人抓获，其交代，将约1L农药硫丹倒人鱼塘中。遂取鱼塘水和死亡的鱼进行毒物检验。     

SPE-GC/MS 法分析鱼塘水中的5种农药

目的：建立鱼类中毒案件中鱼塘水5种农药的固相萃取（solid phase extraction,SPE）结合气相色谱－质谱联用仪（GC/MS）的检测方法。方法比较 Oasis HLB cartridge、Bond Elut C18和 SampliQ C183种固相萃取柱提取、净化鱼塘水中5种农药的提取回收率,并考察洗脱剂种类、洗脱剂用量对提取回收率的影响。结果利用 Bond Elut C18固相萃取柱,以3mL 苯作为洗脱剂,鱼塘水中5种农药质量浓度在1~50μg/mL范围内有良好的线性关系,相关系数为0．9962~0．9996,测得的检出限为3．4~26μg/L,提取回收率为61．49%~102．48%,相对标准偏差均≤3．01%。结论 SPE－GC/MS 法灵敏度高、准确度和精密度好,简单快速,溶剂消耗量少,适用于鱼塘水中5种农药的检测。     

鱼塘水中五氯酚钠的提取及检验探讨

鱼中毒后从鱼塘水中检测毒剂成分比较困难,据调查佛山地区的鱼中毒案件,绝大部分都是五氯酚钠(对鱼毒性极大)所致.为此,笔者专门对此进行了探讨,并连续检测出几宗鱼中毒案件,介绍如下.1 材料和方法1.1 五氯酚乙醇标准液的配制:取五氯酚钠原粉适量加水50ml,搅拌至完全溶解(若有沉淀即过滤,去除滤渣),滴加盐酸直到不再析出自色沉淀,过滤,去除滤液,滤渣反复用蒸馏水洗涤至中性,真空干燥.取干燥粉末0.1g加至10ml容量瓶中,加无水乙醇到刻度.1.2检材提取:提取鱼塘水中的检材,应在死鱼最多的部位提取,或者水不流动的部位提取,并检查鱼塘中及其周围是否有可疑包装物.取检材500ml,放人1000ml梨形分液漏斗中,加盐酸调至酸性(pH=1),剧烈振荡后,加乙醚100ml,充分振摇萃取,静置分层后,将水层转入另一个盛有100ml乙醚的梨形分液漏斗     

固相吸附-GC／MS法检验鱼塘水中农药氰戊菊酯

目的建立鱼类中毒案件鱼塘水中微量农药的分析方法。方法取一定量的吸附剂GDX-403，加入到取出的一定量的鱼塘水中，经振荡吸附，分离出GDX-403，取有机溶剂解析、浓缩，进行GC／MS检验。结果回收率达90％，相对偏差59／5，1000mL水中农药氰戊菊酯检测限浓度在0．2ppb左右。结论该方法操作简便，准确、灵敏度高、可靠性好，可以进行实战推广。     

钓鱼触电身亡 谁负赔偿责任

一．案情简介2004年12月5日上午9时许，周某与何某等五人一起私自到某区茅溪村小岚垭杨某承包鱼塘钓鱼（该鱼塘不对外营业钓鱼）。下午1时20分，周某钓到一条大鱼，为取鱼方便，便将鱼拖至鱼塘右角坎边，叫何某帮助抓鱼。这时周某手中长约6米的鱼竿碰到鱼塘右边上空的某供电局所属1OKV茅石线#4-2至#4-3之间靠#4—3杆10米左右的导线，致使周某被高压电击中，经抢救无效死亡。     

Copper toxicity following massive ingestion of coins

Two hundred seventy-five United States coins were discovered in the stomach of a mentally disturbed individual at autopsy. Many coins containing copper were corroded by prolonged contact with gastric juice, with subsequent absorption and deposition of copper in the liver and kidneys. The patient died from complications related to the acute toxic phase of chronic copper poisoning. A discussion of the case, foreign-body ingestion, gastric bezoars and the mechanism of copper toxicity is presented. To our knowledge, this is the first death due to copper intoxication following a massive ingestion of coins.     

Copper-binding protein in acute copper poisoning

This paper presents a suicide case of copper sulfate ingestion. Post-mortem autopsy revealed mucous membrane necrosis of the esophagus and the stomach. Histological examination revealed centrilobular necrosis in the liver and renal insufficiency. The quantitative determination of copper, zinc and cadmium in various tissues showed that the copper concentrations in blood, liver, kidney and lung were 3.5-24-fold higher than those of the normal level, whereas zinc and cadmium concentrations were within normal range. Chromatographical patterns on Sephadex G-75 showed that most of the accumulated copper in the liver and kidney was bound to metallothionein (MT), a low molecular weight protein with high metal binding capacity which plays a role in the detoxification of heavy metals, while no copper bound to MT was found in the lung. These results suggest that the formation of Cu-induced MT in the liver and kidney occurred at the early stage in fatal acute copper poisoning.     

Identification of Tool Marks of a Sickle on a Telephone Cable

Linkage of a cutting tool (a sickle) with a telephone cable of 100 pairs of copper wires is reported in a case of theft of a telephone cable. Telephone cables contain numerous insulated copper wires of small diameter inside an outer covering and are stolen for the relatively precious copper. The cutting pattern of the cable can only point to the type of the tool but because of the large number of copper wires, it is practically difficult to make a definite linkage with the tool used to cut the cable by comparing the tool marks. The present work reports the successful attempt of the authors in establishing a definite linkage of a stolen telephone cable with a sickle recovered from the suspects. Spot microchemical test was performed for detection of copper on the blade of the sickle, and then tool mark comparison was performed to link the tool marks on the metal strip inside the outer covering of the cable to the blade of the sickle.     

An electrocution by metal kite line

A case is reported in which death is caused due to electrocution by a copper wire that was used as string of the kite. Electric current flowed through the copper wire of cut down kite when it touched power line transmitting alternate current of 240 V at 50 Hz. The free end of copper wire had abraded against the victim's shoulder, neck and face, and finally entangled around the ear. A unique type of electrical injury is noticed due to contact with live copper wire. This paper stresses the unique danger of the kite flying.     

电烧伤皮肤金属元素的测定

本实验系用220V交流电源和直径2.0mm紫铜线为接触电极,在新鲜尸体腹部皮肤上做电烧伤实验。用原子吸收分光光度计对电烧伤皮肤中铜元素含量进行测定。结果表明电烧伤皮肤铜元素含量最高可达137.90μg/g。经10%福尔马林溶液固定40天以上的电烧伤皮肤铜元素含量有昕降低,但仍较正常皮肤含量为高。电烧伤皮肤铜元素含量以电流斑处为最高。本实验为电烧伤皮肤金属元素的定性与定量分析,检材的提取和处理,提供了一个较好的方法,有利于判定案件的性质和确定接触电极的金属种类。     

Physical Characterization and Recovery of Corroded Fingerprint Impressions from Postblast Copper Pipe Bomb Fragments

Pipe bombs made from 1 mm thick copper pipe were detonated with a low explosive power powder. Analysis of the physical characteristics of fragments revealed that the copper had undergone work hardening with an increased Vickers Hardness of 107HV1 compared with 80HV1 for unexploded copper pipe. Mean plastic strain prior to fracture was calculated at 0.28 showing evidence of both plastic deformation and wall thinning. An examination of the external surface showed microfractures running parallel with the length of the pipe at approximately 100 μm intervals and 1–2 μm in width. Many larger fragments had folded “inside out” making the original outside surface inaccessible and difficult to fold back through work hardening. A visual examination for fingerprint corrosion revealed ridge details on several fragments that were enhanced by selective digital mapping of colors reflected from the surface of the copper. One of these fingerprints was identified partially to the original donor.     

An efficient strategy to detect latent fingermarks on metallic surfaces

The aim of this work is to use metal sputtering for the development of latent fingermarks on metallic surfaces by taking advantage of the prints' topography. In order to promote the preferential deposition onto fingerprints' ridges the deposition parameters should be optimized. After a previous selection, copper and gold thin films were deposited by magnetron sputtering onto stainless steel substrates where fingermarks were intentionally placed. After optimizing the deposition parameters, the influence of the fingermarks' age was studied. The quality of the developed fingermarks was evaluated visually and through optical and scanning electron microscopy. The morphology of the copper and gold thin films was examined by high resolution scanning electron microscopy. The preferential magnetron sputtering deposition of copper and gold thin films, 20-30 nm thick, allows latent fingermarks to be successfully developed. The gold films are more promising, especially for detecting non-fresh fingermarks and for conserving the developed marks. It was possible to detect the contours of the ridges and localize minutiae features in a one-month aged impression developed by gold deposition. These films present discontinuous surface and columnar cross-sections, while copper thin films have a featureless morphology.     

弹壳表面指纹的显现方法

使用硝酸银溶液化学反应原理显现枪案现场弹壳表面的指印是一种行之有效的方法。此方法同样可用于子弹、铜钥匙等铜金属表面指纹的显现,效果良好。     

A Comparison of Fingerprint Sweat Corrosion of Different Alloys of Brass

Fingerprint sweat from 40 donors was deposited onto samples of five α and α + β phase brasses, comprising five alloys with different copper and zinc concentrations, two of which also had the addition of small concentrations of lead. Visual grading of the visibility of the corrosion revealed that brasses with the least amount of zinc produced the most visible and fully formed fingerprints from the most donors. Consideration of previously reported mechanisms for the corrosion of brass suggests red copper (I) oxide as a likely corrosion product for low zinc brasses, and a consideration of the color, composition, and solubility of fingerprint sweat corrosion products suggests that copper (I) oxide produces good contrast and visibility with the brass substrate. Scanning electron microscope images of the corrosion of all five alloys confirmed the enhanced contrast between corroded and uncorroded areas for low zinc alloys.     

Effect of chloride ion concentration on the galvanic corrosion of α phase brass by eccrine sweat

Inductively coupled plasma mass spectrometry measurement of the relative concentration of sodium, chloride, calcium, and potassium ions in eccrine sweat deposits from 40 donors revealed positive correlations between chloride and sodium (ρ = 0.684, p < 0.01) and chloride and calcium ions (ρ = 0.91, p < 0.01). Correlations between ion concentration and the corrosion of α phase brass by the donated sweat were investigated by visual grading of the degree of corrosion, by measuring the copper/zinc ratio using energy-dispersive X-ray spectroscopy, and from a measurement of the potential difference between corroded and uncorroded brass when a large potential was applied to the uncorroded brass. An increasing copper/zinc ratio (indicative of dezincification) was found to correlate positively to both chloride ion concentration and visual grading of corrosion, while visual grading gave correlations with potential difference measurements that were indicative of the preferential surface oxidation of zinc rather than copper.