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1.
以溶胶凝胶和交联固化相结合的方法制备了杯[4]芳烃开链冠醚/羟基硅油(Calix[4]open chain ether/OH-TSO)复合涂层固相微萃取探头,采用固相微萃取与气相色谱联用的方法测定水和土壤中的VX.并对自制探头的萃取效率、热稳定性、抗溶剂冲洗能力、使用寿命,保质期以及探头制备重现性等性能进行了系统研究.  相似文献   

2.
固相微萃取是在20世纪90年代初发展起来的新的样品预处理方法,它集萃取、浓缩和进样于一身。具有快速、高效、简便等优点。研究用顶空固相微萃取一气相色谱法测定擦拭样品基质中的芥子气,实验结果表明,该方法在5~280ng间有良好的线性关系,最小检出量为5ng。  相似文献   

3.
详细论述了用固相微萃取-气相色谱法检测水相中的路易氏剂。在此研究基础之上,通过液-固提取方法对土壤基质中的路易氏剂进行提取,提取液经过滤、巯剂化衍生后,直接进行固相微萃取,经气相色谱-火焰光度(硫)检测器进行定量检测。该方法与传统的液-液萃取相比具有简便、快捷、无溶剂消耗、选择性好的特点。最小检出浓度为5ng/ml。在5-300ng/ml的浓度范围内具有良好的线性关系。对土壤中加标化合物的回收率在80%以上。  相似文献   

4.
综述了固相微萃取的装置,原理、发展及其在毒剂分析中的应用.  相似文献   

5.
综述了一种新的样品前处理方法——固相微萃取(Solid—Phase Microextraction,简称SPME),该技术集萃取、富集、进样于一体,具有操作简单、价廉、无污染、易于自动化等优点。针对分析所需的固定相、样品量和容器体积、萃取时间、无机盐的使用、pH值、温度等进行分析,优化反应条件,并对该技术的应用进行了综述。  相似文献   

6.
建立了擦拭棉签基质中路易氏剂的固相微萃取一气相色谱法(SPME-GC)测定方法,结果表明,擦拭棉签基质中加标回收率大于80%;相对标准偏差小于5%。  相似文献   

7.
阳离子表面活性剂CTAB在微乳领域有广泛的应用.以CTAB为表面活性剂,分别将几种不同烷烃作为油相、几种不同醇作为助表面活性剂制备反相微乳体系,对微乳体系增溶纯水和增溶盐溶液时的相行为进行了研究.结果表明,当体系的水相为纯水或盐溶液时,正庚烷作为油相、正丁醇作为助表面活性剂使体系有最佳的增溶效果.  相似文献   

8.
纳米Si-C-N粒子增强Si3N4 复合材料的结构与性能   总被引:2,自引:0,他引:2       下载免费PDF全文
本文用Si-C-N纳米微粉做增强相,Si3N4微粉为基相,采用热压的方法制备了SiCp/Si3N4纳米复相陶瓷,所得的SiCp/Si3N4复合材料的室温弯曲强度为878.5MPa,断裂韧性达11.96MPam1/2,同时应用扫描电镜(SEM)、高分辨透射电镜(HRTEM)对其结构进行了观察,讨论了结构与性能之间的关系。  相似文献   

9.
甲醇气相氧化羰基化合成碳酸二甲酯的研究   总被引:2,自引:0,他引:2  
采用固体离子交换法制备Cu^I/分子筛催化剂和沉淀法制备碱式氯化铜催化剂,利用微反-色谱装置进行活性评价。通过实验发现,当固体离子交换法制备的Cu^I/分子筛催化剂表面生成Cu2(OH)3Cl化合物时,催化剂的转化率、选择性的定量数据得到很大提高;而单纯以沉淀法制备的碱式氯化铜催化剂基本上没有什么活性。  相似文献   

10.
气—固两相自由射流的粒子仿真方法   总被引:3,自引:0,他引:3       下载免费PDF全文
采用粒子仿真方法直接跟踪颗粒相运动轨迹,采用NND格式求解NS方程,数值模拟了气-固两相自由射流流场.计算结果表明,将粒子仿真与CFD方法相结合是研究气-固两相流动问题的有效途径.颗粒相参数变化将对气体流场产生一定影响.  相似文献   

11.
In the Post-Bipolar Era the growing complexity of the military operations requires a new approach for the resolution of international crises. Since the end of the Cold War, peace support operations (PSO) have become the mainstay and principal occupation of most Western armies. At the same time, Italy has been one of the most important actors in such an area. The article focuses on the cooperation between military and civil components (a process called CIMIC) as a key variable in the Italian PSOs. We will analyse in detail the main lessons learned from past military interventions as well as the general context in which new tendencies are taking place. The maintaining of a minimum security frame becomes essential to fulfil activities ‘collateral’ to the mission: reconstructing services and infrastructure, food distribution, water and medication, law and order, de-mining, training of local forces, and supporting local institutions. These are the main tasks to obtain thrust and support from the population.  相似文献   

12.
Energy continues to serve as the bedrock of modern economies and the main driver of modern society. For Africa, the production and supply of energy resources such as crude oil, natural gas, uranium, coal, biomass, biofuels and other renewables are an important source of employment, rents, taxes, royalties and profits. This sector brings in several tens of billions of dollars of revenue annually. The production and delivery of such resources, however, depend on critical infrastructures such as pipelines, refineries, processing plants, terminals, rigs, electrical energy pylons, substations, pump stations, vessels, and tankers. These infrastructures have been attacked by terrorists, insurgents, vandals and saboteurs, all of whom see them as targets against which to register their grievances and extract concessions from the state. This paper is a chronological account of some of the documented incidents of terrorism, insurgency, kidnapping, destruction, sabotage, and human casualties suffered in the oil and gas sectors in Africa between 1999 and 2012. It is based on data extracted from the databases of the RAND Database of World Terrorism Incidents and the University of Maryland's Global Terrorism Database (GTD).  相似文献   

13.
This article demonstrates the inconsistent and wavering Soviet attitude towards national liberation movements in general and the Palestinian organizations in particular. Until the late 1960s, the Soviets viewed these organizations with suspicion, hesitating to engage in political dialogue with them. However, in the 1970s, political and military events in the region, as well as modifications in the Kremlin's Cold War strategies, led to a general shift towards the Middle East in Soviet foreign policy. Soviet leaders showed increased willingness to provide certain Palestinian organizations with arms with which to conduct terrorist activities against Israeli, pro-Israeli, Jewish and Western targets. The article explores the complex relations between Palestinian organizations and the USSR in the field of international terror. The study also exposes and analyzes the nature and content of Soviet–Palestinian arms dialogues and transactions. It provides clear evidence that Soviet policymakers and other luminaries were fully informed of, and sometimes directly involved in, these transactions and dialogues at the highest levels.  相似文献   

14.
The September 11 global crisis prompted by the attacks on the World Trade Center and the Pentagon raises major questions concerning the nature and trajectory of terrorism in the post-Cold War global order. Hitherto, terrorism has been largely debated by analysts at the level of nation states. Terrorist and insurgent movements have also been largely anchored in nationalist and ethnic power bases even when they have sought to mobilise a transnational ideological appeal on religious or class grounds. There have been a few exceptions to this pattern such as the alliance between the German Baader-Meinhof group and the Japanese Red Army Faction, but even such international alliances as this did not, until at least the 1980s, presage anything like a global terrorist network necessitating a global strategic response. This study examines terrorism and global strategic responses.  相似文献   

15.
This article analyses to what extent the Burmese KNU insurgency made use of external support from states, refugees, and diasporas. Based on extensive fieldwork it is concluded that support from neighbouring states and refugees has for years kept the Karen rebellion alive. Western countries perceived forms of resistance to the illegitimate Burmese regime as just and have therefore played a crucial role in the continuation of conflict in Karen State. It is important that policymakers and donors as well as executing organizations continue to reflect critically on the way they exercise their work.  相似文献   

16.
17.
Reviews     
Douglas S. Derrer, We Are All the Target: A Handbook of Terrorism Avoidance and Hostage Survival. Annapolis, MD: US Naval Institute Press, 1992. Pp. x+135, notes, index. $14.95. ISBN 01–55750–150–5

Ian Knight, Zulu: Isandlwana and Rorke's Drift, 22–23 January 1879. London: Windrow & Greene, 1992. Pp.136, 150 illus., incl 8 colour plates, maps, biblio. £35. ISBN 1–872004–23–7

Ian Knight, By the Orders of the Great White Queen: Campaigning in Zululand through the Eyes of the British Soldiers, 1879. London: Greenhill Books and Novato: Presidio Press, 1992. Pp. 272, 17 illus., 1 map. £18.95. ISBN 1–85367–122–3

Manfried Rauchensteiner and Erwin A. Schmidl (eds.), Formen des Krieges: vom Mittelalter zum ‘Low‐intensity’ Conflict’. Graz : Verlag Styria, 1991. Pp.208. DM35. ISBN 3–22–12139–7

Harold J. Kearsley, Maritime Power and the Twenty‐First Century. Dartmouth: Dartmouth Publishing Company, Limited, 1992. Pp.xv + 203, 13 diagrams, index. £32.50. ISBN 1–85521–288–9  相似文献   

18.
装备的RMS是装备的重要设计参数,是影响战备完好和保障能力的关键因素.引入GTST-DMLD作为主要建模工具,建立起装备系统的RMS描述模型,以ESD为补充和扩展,对维修过程进行建模.并以GTST-DMLD-ESD模型作为装备RMS仿真的核心,对装备RMS仿真模型的总体框架进行了研究,并对各模块进行了较为详细的探讨.  相似文献   

19.
20.
ABSTRACT

What was the scope of the Bosnian jihadi participation in the war in Syria? Did the Bosnian volunteers tend to join one particular faction? Why did the Bosnian youngsters decide to join the holy war in the Levant? Was this an organized and hierarchical process or was this a grassroots movement? Last, were all the Salafis in Bosnia supportive of this dynamic or did this process cause internal frictions? These are some of the questions that this research will try to answer.  相似文献   

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