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排序方式: 共有641条查询结果,搜索用时 15 毫秒
231.
试析我国能源运输战略 总被引:7,自引:1,他引:6
马六甲海峡是世界上最危险和最重要的战略要冲之一。专家们认为,它是世界上最容易受到攻击的10大目标之一。控制马六甲海峡是目前美国的主要战略目标,即使可能导致它与该地区的国家甚至和中国发生武装冲突也在所不惜。如果泰国的克拉运河计划最终能够得以实现,一定会给该地区的自由贸易和海运事业带来共同利益。但对中国来说, 必须把缅甸通道和克拉运河区别开来。 相似文献
232.
James R. Jauchem Ph.D. Jennie M. Burns Ph.D. William B. Voorhees M.S. Michael B. Jirjis Ph.D. 《Journal of forensic sciences》2019,64(4):1196-1202
In laboratory studies of the pig Sus scrofa, hematocrit has consistently increased after conducted‐electrical‐weapon (CEW) exposures, possibly due to contraction of the spleen. Splenectomized animals and intact sham control animals were exposed, each for 30 sec, to a benchtop‐produced electrical waveform of net charge levels similar to those of some CEWs. Changes in the blood were compared statistically. Hematocrit increased significantly in both splenectomized and sham animals. There were no significant main‐effect differences between values of hematocrit from the two groups. There were, however, significant interactive effects of time and splenectomy for hematocrit, red blood cell count, and hemoglobin. After peak values were reached for these variables, values returned toward baseline levels more slowly in splenectomized animals. This may have been due to the lack of a spleen to sequester red blood cells (thereby resulting in more cells remaining in the general circulation), unlike sham animals with intact spleens. 相似文献
233.
Abstract: The application of attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectromicroscopy for detection of explosive particles in fingerprints is described. The combined functions of ATR-FTIR spectromicroscopy are visual searching of particles in fingerprints and measuring the FTIR spectra of the particles. These functions make it possible to directly identify whether a suspect has handled explosives from the fingerprints alone. Particles in explosive contaminated fingerprints are either ingredients of the explosives, finger residues, or other foreign materials. These cannot normally be discriminated by their morphology alone. ATR-FTIR spectra can provide both particle morphology and composition. Fingerprints analyzed by ATR-FTIR can be used for further analysis and identification because of its non-destructive character. Fingerprints contaminated with three different types of explosives, or potential explosives, have been analyzed herein. An infrared spectral library was searched in order to identify the explosive residues. The acquired spectra are compared to those of finger residue alone, in order to differentiate such residue from explosive residue. 相似文献
234.
Zuzanna Brożek‐Mucha Ph.D. 《Journal of forensic sciences》2009,54(3):678-681
Abstract: A reconstruction of an incident of a fatal wounding of a football fan with a parachute flare was performed. Physical and chemical examinations of the victim’s trousers and parts of a flare removed from the wound in his leg were performed by means of an optical microscope and a scanning electron microscope coupled with an energy dispersive X‐ray spectrometer. Signs of burning were seen on the front upper part of the trousers, including a 35–40 mm circular hole with melted and charred edges. Postblast residue present on the surface of the trousers contained strontium, magnesium, potassium, and chlorine. Also the case files—the medical reports and the witnesses’ testimonies—were thoroughly studied. It has been found that the evidence collected in the case supported the version of the victim being shot by another person from a distance. 相似文献
235.
Irina Geiman B.S. Marco Leona Ph.D. John R. Lombardi Ph.D. 《Journal of forensic sciences》2009,54(4):947-952
Abstract: The applicability of Raman spectroscopy and surface‐enhanced Raman scattering (SERS) to the analysis of synthetic dyes commonly found in ballpoint inks was investigated in a comparative study. Spectra of 10 dyes were obtained using a dispersive system (633 nm, 785 nm lasers) and a Fourier transform system (1064 nm laser) under different analytical conditions (e.g., powdered pigments, solutions, thin layer chromatography [TLC] spots). While high fluorescence background and poor spectral quality often characterized the normal Raman spectra of the dyes studied, SERS was found to be generally helpful. Additionally, dye standards and a single ballpoint ink were developed on a TLC plate following a typical ink analysis procedure. SERS spectra were successfully collected directly from the TLC plate, thus demonstrating a possible forensic application for the technique. 相似文献
236.
Charles W. Beason M.S. James R. Jauchem Ph.D. C. D. Clark III B.S. James E. Parker M.S. David A. Fines B.S. 《Journal of forensic sciences》2009,54(5):1113-1118
Abstract: Conducted energy weapons (such as the Advanced TASER X26 model produced by TASER International), incapacitate individuals by causing muscle contractions. To provide information relevant to development of future potential devices, a “Modifiable Electronic Stimulator” was used to evaluate the effects of changing various parameters of the stimulating pulse. Muscle contraction was affected by pulse power, net/gross charge, pulse duration, and pulse repetition frequency. The contraction force increased linearly as each of these factors was increased. Elimination of a precursor pulse from X26‐like pulses did not have a significant effect on the normalized force measured. Muscle‐contraction force increased as the spacing increased from 5 to 20 cm, with no further change in force above 20 cm of spacing. Therefore, it is suggested that any future developments of new conducted energy weapons should include placement of electrodes a minimum of 20 cm apart so that efficiency of the system is not degraded. In the current study, the 50% probability of fibrillation level of X26‐like pulses ranged from 4 to 5 times higher than the X26 itself. Relatively large variations about the X26 operating level were found not to result in fibrillation or asystole. Therefore, it should be possible to design and build an X26‐type device that operates efficiently at levels higher than the X26. 相似文献
237.
Indian energy sector has undergone a tremendous transformation with consistent government policy interventions since 2000. Against this backdrop, we examine the extent to which energy poverty has decreased due to the expansion of energy services and the significant determinants of energy poverty in select six states in India. Overall, results reveal that absolute multidimensional energy poverty has substantially decreased across all states examined in the study as well as across all income and social groups between 2015 and 2018. Specifically, acute multidimensional energy poverty has reduced by an average of 30% between 2015 and 2018 in six states. At the same time, dependency on biomass remains more or less the same between 2015 and 2018. Results also show that inequality in the access to energy across income and social groups exists, and education is negatively related to energy poverty. Energy poverty has declined by a similar percentage among most employment groups, except for people practicing cattle rearing. Finally, culture is a significant determinant of energy poverty as households with the elderly and more land owned have higher energy poverty, probably due to the easy access to biomass and preference of such households to use it. 相似文献
238.
优化中国能源结构的政策研究 总被引:2,自引:0,他引:2
大力调整和优化中国能源结构,要在进一步实施节能优先战略的基础上,实行能源多元化、清洁化发展。陔史主要从健全政策法规,保障能源结构优化;完善市场机制,推动能源结构优化;运用先进能源技术,实现能源结构优化三个方面提出了中国能源结构优化的政策措施。 相似文献
239.
Jeffrey D. Wilson 《Third world quarterly》2015,36(2):223-239
The rise of new economic powers has seen increasing attention focused on the international role of the BRICS countries. Importantly, a common feature uniting the BRICS is that they are all resource-rich, and many analysts (and some BRICS governments) have argued that natural resources are one of the key factors propelling the rise of the group. This article explores the BRICS’ emerging status as ‘resource powers’, examining how resource wealth underpins their economic development and foreign policy strategies, and thus contributes to their growing influence in international affairs. It is argued that through the use of nationalistic mining and energy policies, the BRICS governments have exploited natural resources for both domestic economic and international diplomatic objectives. However, there are several challenges and emerging risks facing the BRICS’ resource strategies, which mean that resource wealth is making a positive – though inherently limited – contribution to the growing international status of the group. 相似文献
240.
Alexandra-Maria Bocse 《Contemporary Politics》2015,21(3):294-307
The goal of this article is to critically examine the engagement between the European Union (EU) and a transnational policy network (TPN) that deals with an issue that has grown in importance in the architecture of the EU's energy policy: fracking. The author argues that successful engagement between the EU and networks on shale gas was facilitated by the fact that the TPN or the members of the TPN were in possession of technical and scientific information that is highly needed by institutions in Brussels. Also, the article reveals that the fact that EU energy insecurity has been high on the EU agenda increased EU's interest in actors that could provide vital insights into potential panaceas and palliatives to energy insecurity. 相似文献