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571.
The emergence of hydraulic fracturing techniques is generating a dramatic expansion of the development of domestic natural gas resources in the United States and abroad. Fracking also poses a series of environmental protection challenges that cut across traditional medium and program boundaries. Formal constraints on federal government engagement thus far devolve considerable latitude to individual states for policy development. This provides an important test of whether recent scholarly emphasis on highly innovative state environmental and energy policies can be extended to this burgeoning area. Pennsylvania has moved to the epicenter of the fracking revolution, reflecting its vast Marcellus Shale resource and far‐reaching 2012 legislation. This article examines the Pennsylvania case and notes that the state's emerging policy appears designed to maximize resource extraction while downplaying environmental considerations. The case analysis generates questions as to whether this experience constitutes an influential state early mover that is likely to diffuse widely or is instead an aberration in a rapidly diversifying state policy development process.  相似文献   
572.
Forensic science laboratories perform analyses on a variety of materials using gas chromatography/mass spectrometry (GC/MS). Instruments from different vendors may be used, requiring analysts to be proficient in the use of multiple proprietary software packages for collecting and processing data. There is no standardized GC/MS software available that can acquire data from different vendors' instruments. However, there are third‐party processing software products that can import data files in different formats. The Centre of Forensic Sciences compared the data processing performance of one such product, ACD/MS Manager Suite, with three instrument vendors' software used for casework analysis. This product was tested for its compatibility with the existing software, its capability to load and present data, and to initiate searches of commercial libraries. The study shows that the MS Manager module provides a means for the forensic analyst to view, process, and report on data from different sources in one software package.  相似文献   
573.
It has long been suspected that the illicit distribution of cocaine in the United States has led to a large‐scale contamination of the currency supply. To investigate the extent of contamination, 418 currency samples (4174 bills) were collected from 90 locations around the United States from 1993 to 2009. The extent of their cocaine contamination was quantitated via gas chromatography/mass spectrometry or liquid chromatography/mass spectrometry. The level of cocaine contamination was determined to average 2.34 ng/bill across all denominations ($1, $5, $10, $20, $50, and $100). Levels of cocaine contamination on currency submitted to the Federal Bureau of Investigation Laboratory in criminal cases over the 1993–2001 timeframe had significantly higher contamination than currency in general circulation. A mathematical model was developed based on the background survey that indicates the likelihood of drawing a bill in specific concentration ranges. For example, there is a 0.8349 likelihood that random bill will have contamination less than 20 ng.  相似文献   
574.
The aim of the study is to present the application of a headspace–gas chromatography–mass spectrometry (HS‐GC‐MS) method for the determination of the carbon monoxide (CO) blood concentration and to compare it with carboxyhemoglobin (HbCO) saturation. In postmortem cases, the HbCO measured by spectrophotometry frequently leads to inaccurate results due to inadequate samples or analyses. The true role of CO intoxication in the death of a person could be misclassified. The estimation of HbCO from HS‐GC‐MS CO measurements provides helpful information by determining the total CO levels (CO linked to hemoglobin (HbCO) and CO dissociated from hemoglobin). The CO concentrations were converted in HbCO saturation levels to define cutoff blood CO values. CO limits were defined as less than 1 μmol/mL for living persons, less than 1.5 μmol/mL for dead persons without CO exposure, and greater than 3 μmol/mL for dead persons with clear CO poisoning.  相似文献   
575.
Using a BB gun, it was shown that a gun‐cleaning oil (GCO) can be wiped from the barrel by a projectile and carried much longer distances than those usually associated with solid gunshot residue (GSR). Analysis of GCO subsequently deposited on a target was performed using pentane extraction and gas chromatography. (Hoppe's GCO was used here as a model.) When a 0.45 caliber handgun was used, analysis reveals that most of the GCO wiped from the barrel does not survive, owing to the elevated temperatures encountered. However, two components of the GCO, a long‐chain fatty acid and its ethyl ester, do survive and can be detected in the bullet wipe. This suggests that GCO may be considered as GSR, uniquely detectable at long distances, and that other chemical compounds could either be added to a GCO or directly to bullets, to serve as identifying chemical tags.  相似文献   
576.
目的采用固相萃取-气相色谱法检测全血中佐匹克隆。方法采用Oasis HLB固相萃取柱对样品进行前处理,去离子水、0.5%氨水-甲醇/水((V/V 40∶60)溶液先后淋洗,二氯甲烷/异丙醇(V/V 75∶25)洗脱后进行GC/NPD检测。结果血液中佐匹克隆在50~5 000ng/mL范围内线性良好(R2=0.998 8),平均萃取回收率为96.9%,检出限为30ng/mL,日内RSD为2.1%~5.7%,日间RSD为3.3%~6.2%,结论固相萃取-气相色谱检测法灵敏度高,重现性好,可在血液中佐匹克隆的检测中选用。  相似文献   
577.
电警棍致皮肤损伤的实验研究   总被引:3,自引:2,他引:3  
马骥  徐强 《法医学杂志》1996,12(2):71-73
本研究系用电警棍电击实验动物(猪),观察电击部位的皮肤喷涂金属显色剂后的颜色改变、组织学改变及金属含量的改变。结果表明,电警棍电击机体,不仅可致皮肤产生肉眼可见的损伤,而且可致皮肤细胞产生轻微的极化现象和皮肤金属化,这种金属化可通过金属显色剂喷涂和原子吸收分光光度计检测出来.本实验为电警棍电击伤的定性分析、检材的提取与处理提供了比较好的方法,有利于判定案件的性质和确定电警棍的种类。  相似文献   
578.
目的分析天然气不完全燃烧后废气中毒案件特点,为法医学鉴定以及事故的预防提供参考。方法收集2004—2013年间上海市闵行区天然气不完全燃烧后废气中毒案件22例,从死亡人员一般情况、案件发生时段及天气、现场情况、尸体检验等进行回顾性分析。结果 22例案件中,男性死者15人,女性死者16人,年龄在2~82岁,事发时间主要在1和2月(各8例),事发地点基本在小面积公寓房(21例),所有案件中使用燃气热水器时排气口旁均留有较宽的缝隙。结论通风窗口在燃气热水器排气口旁边的小面积公寓房易发生天然气不完全燃烧后废气中毒事故,在寒冷季节应注意废气中毒现场的勘察。  相似文献   
579.
目的 应用裂解气相色谱-质谱法结合聚类分析,鉴别9个红外光谱相似的汽车中涂漆样品.方法 从漆片中分离、提取出中涂漆样品,用裂解气相色谱-质谱检测并结合红外光谱检测,结果采用SPSS 19统计软件(美国IBM公司)对裂解数据进行聚类分析.结果 裂解气相色谱质谱的检测结果经聚类分析处理,9个中涂漆样品按其裂解图谱的差异可分为4类;而结合红外光谱的检验结果,最终可将5类中涂漆样品一一区分.结论 在汽车中涂漆的鉴别中,裂解气相色谱-质谱检测是对红外光谱检测的重要补充,能够有效地提高对中涂漆的鉴别能力.  相似文献   
580.
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