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51.
Soil samples have potential to be useful in forensic investigations, but their utility may be limited due to the inherent variability of soil properties, the wide array of analytical methods, and complexity of data analysis. This study examined the differentiation of similar soils based on both gross (texture, color, mineralogy) and explicit soil properties (elemental composition, cation exchange, Fe‐oxyhydroxides). Soils were collected from Fallbrook and adjacent map units from Riverside and San Diego Counties in California. Samples were characterized using multiple techniques, including chemical extracts, X‐ray diffraction (XRD), and Fourier transform infrared spectroscopy. Results were analyzed using multiple analytical approaches to compare counties and land uses. Some analyses (XRD, extractions) were better at distinguishing among samples than others (color, texture). Ratios of rare earth elements were particularly useful for distinguishing samples between counties. This potential to “fingerprint” soils illustrates the usefulness of a comprehensive soil database for criminal investigators.  相似文献   
52.
The spectroscopic identification of body fluids in situ is a major objective in forensic science. This approach offers the confirmatory, nondestructive, rapid, and on‐scene identification of various body fluids. Although Raman spectroscopy has shown tremendous promise toward this goal in prior proof‐of‐concept experiments, a significant challenge which still remains is substrate interference. Here, an approach for detecting semen stains in situ on various substrates using Raman spectroscopy is explored. Simulated semen evidence was prepared on skin, glass, and various fabrics. Raman data were accumulated from stains without any pretreatment using a common confocal mapping spectrometer using 785 nm laser excitation. The results demonstrate that the spectroscopic interferences encountered by substrates can be reduced and eliminated using a combination of existing subtraction techniques and chemometric models. Heterogeneous substrates proved most challenging, however, automatic subtraction treatment, and location of fluid hotspots was able to elucidate a clear spectroscopic signature of semen in every instance.  相似文献   
53.
Russia: A Country with an Unpredictable Past   总被引:1,自引:0,他引:1  
Russia is a key player in the Kyoto process, and the fate of the Protocol itself heavily depends on future developments in the country, in particular in its energy sector. This article analyses the contradictory and complex relationships between carbon dioxide emissions, gas exports to Western Europe and the energy security of Russia. The paper reviews emerging trends in the energy sector of Russia that will have a long-term impact on these three parameters and assesses the possible influence of these trends on the implementation of the Framework Convention on Climate Change and the Convention on Long-range Transboundary Air Pollution in Russia. Proceeding from the latest developments in the Russian energy scene, the author tries to forecast how Russia will integrate into the international community in the energy sphere. The study concludes that gas export commitments to Europe will be met despite the serious problems in the domestic gas sector, that energy saving in Russia is the most feasible way of finding a compromise between the three parameters, and that enhancing the energy security of Russia might have rather controversial consequences for Europe.  相似文献   
54.
21世纪日本对外能源战略   总被引:1,自引:0,他引:1  
本文依据关于日本能源方面的新数据,揭示了日本能源进口、利用效率、能源结构和战略储备等新情况。阐述了日本的新国家能源战略,及其基于这一战略的对外能源战略和能源外交。分析日本实行对能源生产国家进行大规模能源合作与国际能源协调的外交政策。提出了包括实现能源来源多元化、加强与传统油气重点地区及国家关系等在内的日本国际能源战略五大方向。并对日本的国际能源战略的动机、效果和战略的恰当与否进行了深入评析。  相似文献   
55.
波长色散X射线荧光光谱法检验纸张中的常量和微量元素   总被引:2,自引:0,他引:2  
目的研究X射线荧光光谱元素分析法对常见纸张的鉴别能力。方法应用波长色散X射线荧光光谱仪对29个纸张样品中常量和微量元素进行了定性和定量分析。结果在样品量为mg级时,不但检出填料中常见的Si、Ca、Mg、Cl等主体元素,还能检出Al、S、P、K、Fe、Sr等10多种微量元素。结论用该方法既可对纸张的种类进行鉴别,对不同品牌的打印纸也有较好的区分。  相似文献   
56.
本方案充分利用发电机余热来达到空调节能的目的,实现能源梯级利用。可大幅度节省运行费用,均衡能源结构,削减夏季电力峰值,填补夏季燃气谷值,减少公用事业投资,属合理用能环保设备,被能源专家大力提倡。  相似文献   
57.
Energy policy in the European Union (EU) faces two major challenges. The first challenge is posed by EUs commitment to reduce greenhouse gas emissions to the atmosphere in the context of the international agreement on climate change. The second challenge is to keep ensuring European security of energy supply, while its dependency on external sources of energy is projected to increase. In this paper, two long-term alternative climate change policy scenarios for Europe are examined. In the first scenario, EU reduces carbon dioxide emissions by domestic measures; in the second scenario EU maximizes cooperation with the countries of the former Soviet Union (FSU). Impacts on carbon flows between the EU and FSU and on the external energy dependency of the EU are assessed with an applied general equilibrium model, GTAP-E, whose set of energy commodities is expanded with combustible biomass as a renewable and carbon-neutral energy commodity. The results show that there is a trade-off between economic efficiency, energy security and carbon dependency for the EU. The FSU would unambiguously prefer cooperation.  相似文献   
58.
Using micro-X-ray fluorescence (MXRF), a novel means of detecting fingerprints was examined in which the prints were imaged based on their elemental composition. MXRF is a nondestructive technique. Although this method requires a priori knowledge about the approximate location of a print, it offers a new and complementary means for detecting fingerprints that are also left pristine for further analysis (including potential DNA extraction) or archiving purposes. Sebaceous fingerprints and those made after perspiring were detected based on elements such as potassium and chlorine present in the print residue. Unique prints were also detected including those containing lotion, saliva, banana, or sunscreen. This proof-of-concept study demonstrates the potential for visualizing fingerprints by MXRF on surfaces that can be problematic using current methods.  相似文献   
59.
The elemental composition and postfiring residues of several "lead-free" or "nontoxic" centerfire handgun ammunition types currently available to the general public were examined. Offerings from Winchester, Remington/UMC, Federal and Speer were obtained from retail sources in both .45 ACP and 9 mm when possible. A total of 112 postfiring residue samples (SEM pins) were collected at varying distances from the muzzle, at two distances from target and from the shooter's hands. An additional 20 samples were collected by direct ignition of primers. Qualitative determinations were carried out using scanning electron microscopy (SEM)/electron dispersive spectrometry (EDS) analysis. All types tested contained aluminum (Al), silicon (Si), copper (Cu), and zinc (Zn). Most contain traces of sulfur and calcium. Winchester WinClean and Remington LeadLess contained potassium as the principle ingredient. Federal BallistClean contained barium, while Speer Lawman CleanFire contained strontium. In the main, these compared favorably with manufacturers' MSDS publications and patents granted. The characterizations undertaken here will be of use to the forensic electron microscopist as these formulations gain popularity.  相似文献   
60.
The Tri-State Crematory Incident in Nobel, GA (February 2001) revealed limitations in traditional human cremated remains (cremains) analytical methodology. The goal of this study was to develop a method for effectively classifying questionable sets of cremains as legitimate or contaminated. Eighty-eight samples of known human cremains, concrete, mixtures of the two, and questionable sets of cremains were acid digested and analyzed for 21 elements by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). Variable cluster and principle component analyses identified the seven elements (Sb, B, Li, Mn, Sr, Tl, and V) used to develop discriminant functions to classify questionable sets into two groups: cremains and concrete. The discriminant analysis shows that at the 0.90 probability level, mixtures of 50% or less human content were classified as concrete. Mixtures with 90% human content classified as cremains. Sixty percent and 75% human content mixtures remained in the questionable classification, but as the concentration of human increased in the mixture, the probability of assignment to the known cremains group increased. Most of the questionable human samples classified as cremains. This is a pilot study and cannot yet satisfy Daubert standards for courtroom admissibility, but it indicates that it is possible to determine the legitimacy of cremains using elemental analysis by ICP-OES coupled with multivariate statistical analysis.  相似文献   
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