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31.
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
32.
R C Carpenter 《Forensic science international》1985,27(3):157-163
Inductively coupled plasma-optical emission spectrometry (ICP-OES) is under evaluation at the Central Research Establishment for the analysis of evidential materials. The analysis of standard reference materials has demonstrated that quantitative multi-element data can be obtained from small samples of a variety of materials. The results of some determinations carried out in support of casework investigations are reported. 相似文献
33.
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
34.
This paper deals with the police officer's or police doctor's ability to find drivers under the influence of drugs. We have also studied whether the protocol on the driver's previous histories of drug intake is useful for directing the chemist in his analytical approach to revealing intoxicants in the suspects' body fluids. A comprehensive procedure for screening traffic-hazardous drugs in the urine was found necessary and is described. By using this method, we have studied the incidence of drunken drivers with detectable medicinal or illicit agents. The results demonstrate that 91% of those drivers found by the officer or doctor of the police to be on intoxicants other than ethanol, carried some kind of traffic-hazardous drug in their body fluids, and that the doctor was a better judge than the police in identifying these offenders. By using a series of chemical methods for drug screening, we found that every third driver suspected of drunken driving due to ethanol, but not to other intoxicants, held some kind of a traffic-hazardous drug substance in his urine; benzodiazepines and cannabinoids were the most common findings. The data imply that 34% of these suspects revealed their intakes of traffic-dangerous intoxicants. We conclude that the judgements of both the officer and doctor of the police are needed for an efficacious detection of drivers under the influence of drugs. Moreover, the results infer that the chemist has to screen for intoxicants to reveal these in a suspect driver. We also conclude that drugs, particularly the benzodiazepines or cannabinoids, may be commonly encountered in drunken drivers, suspected of being inebriated by ethanol but no other toxicants. 相似文献
35.
Several nondestructive and semidestructive analyses were used to discriminate colorless transparent polyethylene bags. Transparent plastic bags made from low-density and linear low-density polyethylene usually contain antiblocking agents to prevent sticking of the film, which makes it difficult to open the mouths of plastic bags. Inorganic antiblocking agents are uniformly dispersed in polyethylene films, so they are easily observed using optical microscopy. The particle size distributions of the antiblocking agents were compared by statistical tests. Particle composition was examined by elemental analysis using energy-dispersive X-ray spectrometry with a scanning electron microscope and by molecular vibration analysis using a sensitive microscopic Raman spectrometer. The compositions could be determined nondestructively on the basis of the results. These data reinforce the morphological discrimination. Morphological discrimination of the dispersed antiblocking agent powders, statistical comparison of particle size distributions, and compositional analysis of the antiblocking agents strengthen the ability to discriminate polyethylene films. 相似文献
36.
Swider C Maguire K Rickenbach M Montgomery M Ducote MJ Marhefka CA 《Journal of forensic sciences》2012,57(4):923-931
Following the September 11, 2001 terrorist attacks, letters containing Bacillus anthracis were distributed through the United States postal system killing five people. A complex forensic investigation commenced to identify the perpetrator of these mailings. A novel liquid chromatography/mass spectrometry protocol for the qualitative detection of trace levels of meglumine and diatrizoate in dried spore preparations of B. anthracis was developed. Meglumine and diatrizoate are components of radiographic imaging products that have been used to purify bacterial spores. Two separate chromatographic assays using multiple mass spectrometric analyses were developed for the detection of meglumine and diatrizoate. The assays achieved limits of detection for meglumine and diatrizoate of 1.00 and 10.0 ng/mL, respectively. Bacillus cereus T strain spores were effectively used as a surrogate for B. anthracis spores during method development and validation. This protocol was successfully applied to limited evidentiary B. anthracis spore material, providing probative information to the investigators. 相似文献
37.
Schäffer M Gröger T Pütz M Dieckmann S Zimmermann R 《Journal of forensic sciences》2012,57(5):1181-1189
Abstract: The chemical profiling of illicit drugs is an important analytical tool to support the work of investigating and law enforcement authorities. In our work, comprehensive two‐dimensional gas chromatography–time‐of‐flight mass spectrometry (GC × GC‐TOFMS) combined with nontargeted, pixel‐based data analysis was adapted for the chemical profiling of 3,4‐methylenedioxymethamphetamine (MDMA). The validity and benefit of this approach was evaluated by analyzing a well‐investigated set of MDMA samples. Samples were prepared according to a harmonized extraction protocol to ensure the comparability of the chemical signatures. The nontargeted approach comprises preprocessing followed by analysis of variances as a fast filter algorithm for selection of a variable subset followed by partial least squares discriminant analysis for reduction to promising marker compounds for discrimination of the samples according to their chemical profile. Forty‐seven potential marker compounds were determined, covering most of the target impurities known from the harmonized one‐dimensional profiling as well as other compounds not previously elucidated. 相似文献
38.
Drug-facilitated sexual assault (DFSA) has been defined as the use of a chemical agent to facilitate a sexual assault. We report two cases of the use of tetrahydrozoline for DFSA. We believe this is the first report with urinary quantification of tetrahydrozoline levels postassault. Blood and urine were obtained c. 20 h postexposure in two cases of reported DFSA. Tetrahydrozoline was not detected in blood but was identified in urine in both victims. After initial identification in the urine using the 2010 update to the AAFS mass spectrometry database library, tetrahydrozoline was quantified at 114 and 150 ng/mL, respectively, using GC/MS. Two unique clinical features reported in these cases were intermittent periods of consciousness and postexposure vomiting. Use of GC/MS was successful in identifying tetrahydrozoline in the 100 ng/mL range up to 20 h postexposure. For victims with late presentation, urine may be a better sample for evaluation for tetrahydrozoline. 相似文献
39.
Speller CF Spalding KL Buchholz BA Hildebrand D Moore J Mathewes R Skinner MF Yang DY 《Journal of forensic sciences》2012,57(5):1354-1360
In 1968, a child's cranium was recovered from the banks of a northern Canadian river and held in a trust until the "cold case" was reopened in 2005. The cranium underwent reanalysis at the Centre for Forensic Research, Simon Fraser University, using recently developed anthropological analysis, "bomb-pulse" radiocarbon analysis, and forensic DNA techniques. Craniometrics, skeletal ossification, and dental formation indicated an age-at-death of 4.4 ± 1 year. Radiocarbon analysis of enamel from two teeth indicated a year of birth between 1958 and 1962. Forensic DNA analysis indicated the child was a male, and the obtained mitochondrial profile matched a living maternal relative to the presumed missing child. These multidisciplinary analyses resulted in a legal identification 41 years after the discovery of the remains, highlighting the enormous potential of combining radiocarbon analysis with anthropological and mtDNA analyses in producing confident personal identifications for forensic cold cases dating to within the last 60 years. 相似文献
40.
Abstract: Consumer complaints received by the U.S. Food and Drug Administration in August 2010 about raw organic almonds tasting “bitter” opened an investigation into the presence of bitter almonds in the imported product. Bitter almonds (Prunus amygdalus) contain the cyanogenic glucoside amygdalin, which hydrolyzes to produce cyanide. Ultraviolet–visible spectrophotometry was used to detect and quantitate cyanide, and liquid chromatography‐mass spectrometry was utilized to detect amygdalin in the submitted samples. Control bitter almonds were found to contain 1.4 mg cyanide/g and an estimated level of 20–25 mg amygdalin/g. The questioned samples contained between 14 and 42 μg cyanide/g and were positive for the presence of amygdalin. Sweet almonds were found to be negative for both compounds, at levels of detection of 4 μg cyanide/g and 200 μg amygdalin/g. 相似文献