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11.
This article suggests that the War on Terrorism is actually a campaign against a globalized Islamist 1 1 In this article, the term ‘Islamist’ describes the extremist, radical form of political Islam practiced by some militant groups, as distinct from ‘Islamic’, which describes the religion of Islam, or ‘Muslim’, which describes those who follow the Islamic religion. In this article the term is used to refer primarily to Al Qaeda, its allies and affiliates. View all notes insurgency. Therefore, counterinsurgency approaches are more relevant to the present conflict than traditional terrorism theory. Indeed, a counterinsurgency approach would generate subtly, but substantially different, policy choices in prosecuting the war against Al Qaeda. Based on this analysis, the article proposes a strategy of ‘disaggregation’ that seeks to dismantle, or break, the links in the global jihad.2 2 This article uses the short form of the Islamic term jihad to mean ‘lesser jihad’ (armed struggle against unbelievers), rather than ‘greater jihad’ (jihad fi sabilillah), i.e. moral struggle for the righteousness of God. View all notes Like containment in the Cold War, disaggregation would provide a unifying strategic conception for the war – a conception that has been somewhat lacking to date.  相似文献   
12.
This article consists of selected translations from captured interviews and dairies of Al Qaida members. The time period covered is from mid-2001 to early 2002 and concerns their operations in Afghanistan. The material clearly conveys a range of emotion, from confident to despondent, as well as efforts to contest the US actions. The first several pages give the reader context and some possible “lessons learned,” but the story(ies) are best told by the Al Qaida members themselves. All names are pseudonyms.  相似文献   
13.
Although the environmental movement was established in the West, there is currently an Islamist variant that has received less attention. The Quran and the Hadiths provide guidance for the faithful on the relationship between Allah, humanity and nature. The article will examine and compare the environmental agendas of six Islamist groups: Hizb'allah, Hizb ut-Tahrir, Hamas, the Muslim Brotherhood, Jamaat-e-Islami, and al Qaeda. While they all share similar concerns, Islamists have developed globalized, glocalized, or localized ‘scales’ of engagement, depending on the targeted audience. Finally, the article will examine the security implications of Islamist environmentalism, including the possibility of an alliance between Islamists and militant environmentalists.  相似文献   
14.
The storage stability of energetic materials is important for its application. Here, the storage stability of Al/CuO nanothermite, which was prepared by electrospray method and stored with different storage time, was systematically researched. The activation energy of Al/CuO nanothermite was calculated by differential scanning calorimetry (DSC). The ignition temperature and the curve pressure history of Al/CuO nanothermite was measured using ignition temperature measuring device and constant-volume pressurization tests, respectively. Further, the thermites were characterized by X-ray Diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and Transmission electron microscopy (TEM). The results show that the morphology of the thermites did not change significantly. The activation energy was decreased from 254.1 kJ/mol to 181.8 kJ/mol after storage for 13 months. When stored for 0, 7 and 13 months, the peak pressures of Al/CuO nanothermite were 685.8 kPa, 626.3 kPa and 625.5 kPa, respectively. In addition to the ignition temperature, it was 775 ℃, 739 ℃ and 754 ℃, respectively. This result indicated that the ignition and combustion properties of Al/CuO nano-thermite are obviously reduced when stored for a long time, at room temperature.  相似文献   
15.
分别采用交流阻抗、线性极化、动电位扫描等电化学方法初步研究了羧酸盐缓蚀剂在中性介质中对锡和铝的缓蚀作用.实验结果表明,锡和铝在中性介质中的腐蚀以点蚀为主,而该羧酸盐结构中含有羧基,对锡和铝有良好的缓蚀效果,尤其是处于最佳缓蚀浓度时.  相似文献   
16.
对空气饱和与水饱和两种情况下的通孔泡沫铝以及闭孔泡沫铝开展了水下隔声性能实验研究。实验结果表明:在[500,4 000]Hz范围内,水饱和通孔泡沫铝和闭孔泡沫铝具有良好的隔声性能,而空气饱和通孔泡沫铝水下隔声性能相对较弱。与现有橡胶类水声去耦材料相比,水饱和通孔泡沫铝具有良好的低频、宽带隔声特性以及耐压且不受温度的影响等特点,可以作为一种潜在的性能优良的水声去耦材料。  相似文献   
17.
ABSTRACT

Al Qaeda following 9-11 experienced a period of stagnation which it sought to remedy through a project of re-branding. Critical of this approach, Islamic State claimed that al Qaeda was an elitist organization that had facilitated the stagnation of the Salafi Jihadist project. In an attempted to claim dominance over the jihad, Islamic State’s endeavored to discredit al Qaeda through a process it presented as ideological correction, linked to Islamic eschatology, sectarian agitation, permissive violence, and the caliphate. Following Islamic State’s acquisition of vast territory in Iraq and Syria, arguments proliferated that Islamic State had surpassed al Qaeda. As the caliphate has collapsed what effects will this have on al Qaeda’s fortunes and strategy? It is argued that Islamic State has provided al Qaeda’s strategic approach with renewed vigour to help ensure its survival and pursue resurgence. Al Qaeda acting in concert with the meta-strategy for survival concept, has altered an existential threat into an advantage through disavowing Islamic State’s methods, continuing to engage with localism, and pursuing rebranding by positioning itself as a moderate alternative. The cases of al Qaeda affiliates in Yemen, Syria, West Africa, and South Asia are instructive in assessing the effectiveness of al Qaeda’s resurgence.  相似文献   
18.
《防务技术》2022,18(9):1688-1696
The Al and La elements are added to the Sn9Zn alloy to obtain the fusible alloy for the mitigation devices of solid propellant rocket motors. Differential scanning calorimetry (DSC), metallographic analysis, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), tensile testing and fracture analysis were used to study the effect of Al and La elements on the microstructure, melting characteristics, and mechanical properties of the Sn9Zn alloy. Whether the fusible diaphragm can effectively relieve pressure was investigated by the hydrostatic pressure at high-temperature test. Experimental results show that the melting point of the Sn9Zn-0.8Al0·2La and Sn9Zn–3Al0·2La fusible alloys can meet the predetermined working temperature of ventilation. The mechanical properties of those are more than 35% higher than that of the Sn9Zn alloy at −50 °C–70 °C, and the mechanical strength is reduced by 80% at 175 °C. It is proven by the hydrostatic pressure at high-temperature test that the fusible diaphragm can relieve pressure effectively and can be used for the design of the mitigation devices of solid propellant rocket motors.  相似文献   
19.
《防务技术》2014,10(1):22-27
Ni–Al alloy coatings with different Y additions are prepared on 45# medium steel by laser cladding. The influence of Y contents on the microstructure and properties of Ni–Al alloy coatings is investigated using X-ray diffraction, scanning electron microscopy, electron probe microanalyzer, Vickers hardness tester, friction wear testing machine, and thermal analyzer. The results show that the cladding layers are mainly composed of NiAl dendrites, and the dendrites are gradually refined with the increase in Y additions. The purification effect of Y can effectively prevent Al2O3 oxide from forming. However, when the atomic percent of Y addition exceeds 1.5%, the extra Y addition will react with O to form Y2O3 oxide, even to form Al5Y3O12 oxide, depending on the amount of Y added. The Y addition in a range of 1.5–3.5 at.% reduces the hardness and anti-attrition of cladding layer, but improves obviously its wear and oxidation resistances.  相似文献   
20.
对K2Al2B2O7(KABO)晶体的相位匹配飞秒激光参量放大(OPA)特性进行了系统的理论计算和分析。分别讨论了Ⅰ型、Ⅱ型参量放大共线以及非共线情况,计算了在不同非共线夹角下的相位匹配角度。研究结果表明:对于一定波长的抽运光,存在一定的非共线入射角对应一定波长的信号光。在KABOⅠ型参变条件下,非共线角的引入使相位匹配角增大。这对于高效率地产生脉宽极短的飞秒参量激光、扩大飞秒激光的调谐范围以及通过参量技术放大飞秒脉冲都具有重要的意义。  相似文献   
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