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81.
Elemental Characterization and Discrimination of Nontoxic Ammunition Using Scanning Electron Microscopy with Energy Dispersive X‐Ray Analysis and Principal Components Analysis
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Seth R. Hogg Ph.D. Brian C. Hunter M.D. Ruth Waddell Smith Ph.D. 《Journal of forensic sciences》2016,61(1):35-42
Concerns over the toxic by‐products produced by traditional ammunition have led to an increase in popularity of nontoxic ammunition. In this work, the chemical composition of six brands of nontoxic ammunition was investigated and compared to that of a road flare, which served as an environmental source with similar composition. Five rounds of each brand were fired while a further five were disassembled and the primer alone was fired. Particles collected from all samples, including the road flare, were analyzed by scanning electron microscopy with energy dispersive X‐ray analysis. Common elements among the different ammunition brands included aluminum, potassium, silicon, calcium, and strontium. Spectra were then subjected to principal components analysis in which association of the primer to the intact ammunition sample was generally possible, with distinction among brands and from the road flare sample. Further, PCA loadings plots indicated the elements responsible for the association and discrimination observed. 相似文献
82.
目的探讨致命室性快速型心律失常(LVTA)能量代谢相关变化及氧化损伤。方法建立以乌头碱(ACO)注射和冠脉结扎(CAL)心肌缺血诱导的LVTA-心脏性猝死(SCD)SD大鼠模型,以过度麻醉(PI)及冠脉结扎心衰致死(CAL-B)为各自对照,检测心室肌线粒体膜电位(MMP)、活性氧(ROS)、丙二醛(MDA)、磷酸肌酸(PCr)及血清肌钙蛋白I(cTnI)含量,并进行比较。结果成功制备ACO-LVTA及CAL-LVTA大鼠14只及6只。与各自的同行对照比较,ACO-LVTA组及CAL-LVTA组心室肌的ROS及MDA呈升高的趋势,PCr呈下降的趋势,其中CAL-LTVA的MDA显著高于其同行对照(P0.05)。ACO-LVTA组心室肌的MMP低于对照组,但高于CAL处理的两组。CAL-LVTA组血清cTnI高于对照组,且显著高于ACO-LVTA组及其对照与处理前(P0.01),ACO-LVTA组血清cTnI高于对照组与处理前。心肌ROS水平与VT及VF持续时间相关(P0.05),相关系数分别为0.44、0.46。结论发生LVTA后,心室肌MMP及PCr下降、ROS、MDA升高,血清cTnI升高,表明LVTA可导致能量代谢改变及氧化损伤,可能与线粒体功能异常相关。 相似文献
83.
Although officially Russian state-owned energy companies operate as independent entities, their actions often lead to suspicion that they are acting as a tool of Russian state foreign policy. Countries on the southeastern borders of Europe – Bulgaria and Greece – are prime examples of where this might be the case, since they not only have a central position in Russia’s plans to penetrate European markets through new transport infrastructure but are also part of competing plans for routing non-Russian gas to Western markets. The main focus of the present research is on the natural gas and oil sectors, as these are the traditional foundation of Russian energy exports to Europe. The aim of this paper is thus to provide an objective, evidence-based analysis of Russian activities in the natural gas and oil sectors of Greece and Bulgaria in order to establish whether its actions have been implicitly or explicitly politicized and have served to strengthen Russian influence in the region. 相似文献
84.
中国发展低碳经济的路径选择 总被引:1,自引:0,他引:1
陈柳钦 《四川行政学院学报》2010,(1):72-74
以低能耗、低污染、低排放为基础的低碳经济是人类社会的一大进步,国外已采取多种措施发展低碳经济。发展低碳经济,是中国做负责任的大国、实现和平崛起和可持续发展的必然选择。中国应采取多种措施发展低碳经济。 相似文献
85.
Alex O. Acheampong Eric Evans Osei Opoku Olufemi Adewale Aluko 《Journal of Public Affairs (14723891)》2023,23(4):e2882
Global crises have heightened policy uncertainties and efforts to address global climate change. Limited evidence exists in the literature on geopolitical risk's direct and indirect roles in addressing global emissions. In this study, we examine whether geopolitical risk could impede or facilitate efforts to attain a net-zero emissions target through energy transition using panel data for 42 countries from 1990 to 2020. Various econometric techniques were applied in this study to present robust findings and reliable conclusions. Estimates from the Driscoll-Kraay, Lewbel two-stage least squares and method of moment regression techniques consistently showed that countries' geopolitical risk directly increases emissions (total greenhouse gas, carbon, methane, and nitrous oxide). At the same time, energy transition, measured with renewable energy consumption, mitigates these emissions. In addition, evidence from the partial linear functional-coefficient model technique indicates that renewable energy consumption consistently mitigates emissions when geopolitical is minimal (at a minimum and mean level). However, the role of renewable energy consumption in reducing emissions becomes weaker when geopolitical risk is heightened—thus, when geopolitical risk reaches its maximum level. We recommend that efforts to sustain renewable energy transition and maintain geopolitical stability are vital for achieving net-zero emissions and climate change mitigation. 相似文献
86.
Political ideology is an increasingly powerful force in support of public policy. Historically, nuclear energy has found more support among political conservatives. This study updates the literature on political ideology and support for nuclear energy by examining how political ideology is associated with perceptions of nuclear energy and trust of nuclear information sources. After excluding participants with incomplete data, and participants within 50 miles of a nuclear reactor, the analytical sample size for the analysis examining political ideology and perceptions of nuclear energy was 4153. The analytical sample includes a total of 1035 participants within a 50-mile radius of INL, 710 participants from within Idaho who lived further than 50 miles from INL, 1899 participants from other states (more than 50 miles from a nuclear reactor), and 509 Non-Idaho participants living within 50 miles of a nuclear reactor. Logistic regression was used to determine how political ideology was associated with perceptions of nuclear energy and trust in different sources regarding radioactive waste, after controlling for demographics and location. While liberal participants near INL were less favorable towards nuclear energy, and more trusting in impact scientists to tell the truth about radioactive waste than their conservative counterparts, this was not consistent across the US. Our findings reveal the complexity of political ideology and the perceptions of nuclear issues and how proximity influences perceptions. The perceptions of political moderates were particularly important in providing a more complex understanding of political ideology and nuclear energy issues. 相似文献
87.
新安全视角下美国政府的气候政策 总被引:1,自引:0,他引:1
"人类安全"逐渐成为一种新的安全理念,环境气候问题等各种影响人类安全和福祉的非传统安全问题日益引起广泛关注。全球性安全威胁的严重程度则取决于治理框架的反应能力。包括气候政策、法律和机构在内的气候环境治理框架能够最大限度地削弱全球化冲突的根源,避免影响的发生或减缓其进程。奥巴马上任以来美国新政府能源、环境和应对气候变化政策出现较大调整,大力推动新能源法案来减缓气候变化。这一政策转向具有深刻的历史动因和政治基础,并将给美国经济复苏和美国企业的国际竞争力带来压力,加剧美国对外贸易摩擦和削弱其在国际气候环境合作中的领导地位。 相似文献
88.
中、俄、蒙三国的油气合作 总被引:2,自引:1,他引:1
中国处于石油资源相对贫乏的东亚西太平洋区域,总体石油资源不足;俄罗斯东西伯利亚和远东地区的石油和天然气储量丰富,蒙古石油矿藏集中在中蒙两国边界地区,这为中、俄、蒙的油气合作提供了可能,并且从蒙古直接穿过进入中国的中俄石油管道是最近、最安全的线路。从未来发展的趋势看,中国可积极利用俄蒙的资源投资与合作,参与输气、输油管道的建设,拓宽和夯实中俄油气合作的经济基础。 相似文献
89.
煤炭、石油、电力等能源的供应危机是战后日本经济复兴中最大的“瓶颈约束”。日本为确保经济发展所需的能源动力,选择了具有“国家管制”和“行政计划”特征的能源配置框架;确立了优先加强能源“量”的增产和供应而非“利润”和“效益”的政策目标;运用了行政约束、法律强制、精神动员等多元化的政策工具。日本舒缓和规避能源“瓶颈约束”的政策构想源于统制经济思想。 相似文献
90.
Analyzing and Interpreting Lime Burials from the Spanish Civil War (1936–1939): A Case Study from La Carcavilla Cemetery
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Eline M. J. Schotsmans Ph.D. Almudena García‐Rubio M.Sc. Howell G. M. Edwards Ph.D. Tasnim Munshi Ph.D. Andrew S. Wilson Ph.D. Luis Ríos Ph.D. 《Journal of forensic sciences》2017,62(2):498-510
Over 500 victims of the Spanish Civil War (1936–1939) were buried in the cemetery of La Carcavilla (Palencia, Spain). White material, observed in several burials, was analyzed with Raman spectroscopy and powder XRD, and confirmed to be lime. Archaeological findings at La Carcavilla's cemetery show that the application of lime was used in an organized way, mostly associated with coffinless interments of victims of Francoist repression. In burials with a lime cast, observations made it possible to draw conclusions regarding the presence of soft tissue at the moment of deposition, the sequence of events, and the presence of clothing and other evidence. This study illustrates the importance of analyzing a burial within the depositional environment and taphonomic context. 相似文献