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131.
Java多线程技术在网络通信系统中的应用   总被引:1,自引:0,他引:1  
介绍了Java的关键环节多线程技术,详细说明了线程的创建、调用方法及如何实现线程的同步及相互间通信,阐述了套接字(Socket)基本原理及概念,结合一个多用户并发服务器的网络通信程序实例,说明多线程客户机/服务器模式网络通信程序开发的一般方法。  相似文献   
132.
GC/MS同时分析头发中大麻酚类和△^9-四氢大麻酸   总被引:2,自引:0,他引:2  
目的建立同时分析毛发中THC、CBN、CBD和大麻主要代谢物THC-COOH的方法.方法头发检材去污处理后,加入内标氯灭酸,经NaOH水解和正己烷:乙酸乙酯(9:1)提取,吹干后衍生化,利用GC/MS-SIM方法分析.结果THC、CBN和THC-COOH的最低检出限分别为0.01、0.05和0.01ng/mg.10例阳性头发中均检出THC成分,THC浓度范围为0J 1~8.84ng/mg,有3例未检出THC-COOH,检出者的量亦低于定量下限.结论同时分析头发中的大麻酚类和△9-四氢大麻酚是可行的,头发中THC-COOH浓度明显都低于THC浓度.  相似文献   
133.
GC/TSD法检验杀虫双   总被引:3,自引:1,他引:2  
刘颖 《刑事技术》2003,(5):26-27
目的建立一种杀虫双的GC分析方法。方法应用HP-5弹性石英毛细管柱(30m×0.53mm×1.5μm),用GC/TSD方法对生物检材中的杀虫双进行检验。结果可以快速、有效地检出中毒死亡者胃内容中的杀虫双成分。结论该方法简单、准确、快速,可很好地应用于案件的检测工作。  相似文献   
134.
WTO的环境立场与环境规则   总被引:3,自引:0,他引:3  
当环境保护和可持续发展成为世界主流之时,作为经济贸易协调机制的GATT-WTO也对之充分重视。通过30年的研究、讨论、争端解决过程,WTO逐渐确立了其对环境问题的态度,在贸易规则中加入环境保护的内容。但是这些规则仍有待于进一步深化、具体和明确。可以预期环境问题将会成为国际贸易中的主要问题,面临着2002年约翰内斯堡世界可持续发展峰会,WTO的多哈回合会在环境问题上建立更多的规则。中国应当在国际法和国内法层面为实现可持续发展努力。  相似文献   
135.
A series of side chain regioisomers of 3-methoxy-4-methyl- and 4-methoxy-4-methyl-phenethylamines have mass spectra essentially equivalent to the controlled drug substance 3,4-methylenedioxymethamphetamine (3,4-MDMA), all have molecular weight of 193 and major fragment ions in their electron ionization mass spectra at m/z 58 and 135/136. The acetyl, propionyl and trifluoroacetyl derivatives of the primary and secondary regioisomeric amines were prepared and evaluated in GC–MS studies. The mass spectra for these derivatives were significantly individualized and the resulting unique fragment ions allowed for specific side chain identification. The trifluoroacetyl derivatives provided more fragment ions for molecular individualization among these regioisomeric substances. These trifluoroacetyl derivatives showed excellent resolution on a non-polar stationary phase such as Rtx-1.  相似文献   
136.
This study is an extension of a previous evaluation of a program (Red Flag/Green Flag) in which children, parents, and teachers were exposed to a workbook and film designed to teach personal safety strategies for preventing sexual victimization or encouraging adult assistance through disclosure of such incidents. In the current investigation, only children and their teachers received this didactic training program. Children and teachers from neighboring schools were assigned to a Training or Control group. Self-reports from children, teachers, and parents, as well as guidance counselor incident reports, were obtained to evaluate outcome. Results indicated greater gains in general knowledge and prevention skills at post-training and 6-month follow-up for trained than control children. Some improvements were made by trained teachers and parents of trained children. Child reports of personal experiences and guidance counselor incident reports were in accord with the assistance component of the program. However, the pattern of reports across sources is difficult to interpret. The findings are discussed in light of salient issues regarding the content of training, child disclosure, and methodology.  相似文献   
137.
采用RT-PCR方法对1株H9N2亚型禽流感病毒Ck/GS/2/99株RNA聚合酶基因PB2、PB1和PA分别进行了扩增,将其克隆到pGEM-T easy载体后进行序列测定与分析。结果表明,该株病毒的PB2、PB1和PA基因开放阅读框(ORF)分别由2280、2274和2 151个碱基组成,分别编码759、757和716个氨基酸。经同源性与系统发生树分析,该毒株RNA聚合酶基因PB2、PB1和PA与Ck/NX/4/99株的核苷酸和氨基酸同源性均在98%以上,另外这3个基因与Dk/HK/Y280/97、Sw/HK/9/98和Qu/HK/NT/28/99株的关系密切。  相似文献   
138.
This paper presents findings from the first study of female prisoners' self-reports of criminal activity. Using the criminal career paradigm to frame the analysis, self-reported estimates of crime participation and frequency rates were examined for eight felony crimes. Important similarities between women and men were found in overall patterns of crime. Specifically, a small proportion ofboth women and men described committing a large portion of the total crimes reported. These data also suggest that women and men are similar in violent crime participation — a finding that varies from the current literature. Once active in a crime type, women and men committed assault, theft, and forgery at significantly different rates; no gender differences were found in the annualized frequency rates of burglary, robbery, motor vehicle theft, fraud, and drug dealing. However, although statistical differences were not found in the overall frequency of drug dealing, specific patterns of drug dealing reflected considerable gender variation, with a larger proportion of the female sample committing very frequent (daily) drug dealing activity. The findings reflect the value of the criminal career paradigm for the study of gender differences. Future research should include largescale quantitative designs that allow detailed analyses of correlates of the distinct criminal career dimensions.Points of view are those of the author and do not necessarily reflect the official position of the U.S. Department of Justice.This research was funded in part by the National Institute of Justice, Grant 87-IJ-CX-0048.  相似文献   
139.
本文研究了一种同时测定生物样品中二氯苯醚菊酯、氯氰菊酯、杀火菊酯、溴氰菊酯的方法,并详细介绍了试管提取净化的过程。在安装电子捕获检测器的气相色谱仪上,选择不同极性的色谱柱和优选操作参数,能使上述4种杀虫剂达到基线分离,并在20~25分钟内同时完成分析。添加生物样品肝、胃,脑、血中的回收率达到70~90%;变异系数在±0.03~0.08范围。应用本文建立的方法,对中毒兔(溴氰菊酯和杀灭菊酯)各脏器均检出了原体杀虫剂,并成功地运用于一些法庭中毒案件的鉴定。  相似文献   
140.
POPULATION: Population: Illinois Caucasian ( n =117), Illinois African American ( n =218), and Illinois Hispanic ( n =68).  相似文献   
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