IPv6和IPv4的共存与过渡及其应用

分析了IPv4向IPv6过渡的技术,指出了IPv6在农业信息化中的广阔应用前景.     

Phage and MLVA Typing of Salmonella Enteritidis Isolated from Layers and Humans in Belgium from 2000–2010, A Period in which Vaccination of Laying Hens was Introduced

The aim of the study was to characterize isolates of Salmonella enterica serovar Enteritidis (S. Enteritidis) obtained from humans and layer farms in Belgium collected during 2000–2010. Three periods were compared, namely (i) before implementation of vaccination (2000–2004), (ii) during voluntary vaccination (2005–2006) and (iii) during implementation of the national control program (NCP) for Salmonella including mandatory vaccination against S. Enteritidis (2007–2010). The characteristics compared across time periods were distributions of phage type and multiple‐locus variable number tandem‐repeat assay (MLVA). While PT4 and PT21 were predominantly isolated in Belgium in layers and humans before 2007, a significant reduction of those PTs was observed in both populations in the period 2007–2010. The relative proportion of PT4b, PT21c and PT6c was found to have increased considerably in the layer population since 2007. In the human population, PT8, PT1 and the group of ‘other’ PTs were more frequently isolated compared to the previous periods. When comparing the proportion of the predominant MLVA types Q2 and U2, no significant difference was found between the layer and human population in the three periods and between periods within each category (layer and human). A significant difference in isolate distribution among MLVA clusters I and II was found between human and layer isolates recovered during Period 3 and in the human population between Period 1 and 3. Results suggest that the association between S. Enteritidis in layers and the occurrence of the pathogen in humans changed since implementation of the NCP in 2007.     

四种动物凝血三项值初探

为了探索正常生理状态下4种动物的凝血3项值,分别用凝血酶原时间测定试剂盒、自制兔脑粉浸出液、自制鸡脑粉浸出液测定了鸡、鲤鱼、犬和羊4种动物的血浆凝血酶原时间(PT),用试剂盒测定了4种动物的凝血酶时间(TT)和活化部分凝血酶原时间(APTT).结果表明:3种方法测定的4种动物的PT值在相同动物间无显著差异(P>0.05),说明有颌类脊椎动物体内的组织因子在启动血液凝固的作用上具有进化的保守性;4种动物的凝血3项值分别为鸡PT 43.42 s ,TT 16.85 s ,APTT 91.33 s;鲤鱼PT 73.39 s ,TT 20.75 s ,APTT 12.80 s;犬PT 10.70 s ,TT 13.32 s ,APTT 25.89 s;羊PT 23.29 s ,TT 8.04 s ,APTT 25.92 s.     

PT 2262和MICRF 001和87 C 196 KC 组成的编译码系统设计

详细论述了将PT2262和MICRF001和87C196KC组成的编译码系统用于机动车防盗器中时的系统软硬件设计方法及系统的抗干扰措施。路载试验表明：系统运行稳定,可靠性好,抗干扰能力强,保密性好,功能识则准确无误。     

TNE EXPERIMBNT RESEARCH OF PT THIN FILM USED IN INFRARED DETECTOR

The preparation technology and thermal treatment PT thin film used in infrareddetector and photo-electron devices are studied. The er thin film prepared by multi-ion-beam reac-tive co-sputtering apparams are analysised by x-ray , XPS and EPMA. The impurity of PbO,Pb2Ti2O6 in PT thin film is eleminated and PbTiO3 (001)preferred orientation is improved. The rea-sonable teperature of substrates is given in this paper.     

农业机械中冷却水温监控报警系统的研制

系统采用高性能STC89C52单片机作为核心,加温度采集模块、温度显示和报警模块、语音播报模块、远程温度监控模块组成。该系统利用铂电阻PT100采集温度,通过12位AD转换芯片TLC2543对温度信号采样、转换,将结果送入单片机中通过数码管显示并可以实现按键语音播放,同时,利用射频通信技术进行远程温度监控。结果表明,温度采集能够精确采集外界温度且误差小于0.1℃,测量范围为0～90℃;温度上下限设定时伴有语音提示,步进值精确到0.05℃;实际温度超出所设温度上下限时,会发出报警声。最终还将会前方的数据传送到后方监控系统进行实时监控,并且记录监控对象出现的异常状况的准确时间,以备查阅。     

基于单片机和无线电遥控技术的网衣升降控制系统设计

为了减轻网箱养殖捕捞和网衣维护的劳动强度,应用单片机和无线电遥控技术实现网衣升降自动控制。文章介绍了PT2262编码器和PIC16C57单片机的主要性能特点,详细叙述了基于PT2262编码器的无线遥控发射器和基于PIC16C57单片机的接收控制器的工作原理、电路设计和软件编程技术等。无线发射器既可以单独控制某个无线接收解码控制器,也可以同时控制多个无线接收解码控制器工作。系统使用方便,稳定可靠,具有正反转控制、自锁与互锁以及自学习等功能。     

转多基因杨树中抗生素标记基因N PT II表达量分析研究

对转基因库安托杨及银腺杂种杨(含1～5个外源基因)中选择标记基因新霉素磷酸转移酶基因(NPTⅡ)进行PCR扩增,证实该基因稳定存在于转基因杨树的基因组中.应用酶联免疫吸附测定法(ELISA)对2种转基因杨树中NPTⅡ蛋白的表达量进行定量检测,结果显示:NPTⅡ蛋白的表达量并没有随着目的基因数量的增加而升高,说明与转单个基因杨树相比,转多个基因杨树可能由标记基因引起的生物安全问题并不会加剧.