一种微型化通用数据采集控制模块的设计与实现

针对信息化时代，工业控制、医疗设备、航空航天的发展，对高精度数据采集系统的综合性能和尺寸提出越来越严格的要求。因此，设计了一种可靠的微型化通用数据采集控制模块，采用尺寸规格为4 mm×5 mm的模块板卡，以FPGA和STM32作为核心处理器，存储模块为32 GB EMMC，接口包括以太网、USB、CAN、RS232、RS422和RS485,FPGA负责数据采集和信号处理，STM32负责数据存储以及对外通信。FPGA和STM32之间数据交互、STM32和EMMC之间数据存储、STM32通过以太网、USB、CAN、RS232、RS422和RS485总线对外通信的模拟试验结果表明：该数据采集系统具有很高的综合性和可靠性。     

51单片机和PC机串行通信系统设计

介绍51系列单片机和PC机进行串口通信硬件电路的设计原理及通信软件的设计原理和方法,并给出硬件原理图及通信软件程序。重点介绍在VC 环境下如何通过W indows API通信函数实现对串口的操作。     

基于STM32的CAN转USB模块设计

在有关CAN总线通信的嵌入式设计中,经常需要PC机作为调试工具,以便在PC机上直观地观察数据,这就需要CAN转USB设备进行连接。笔者选用低成本的内部集成了CAN控制器和串口的ARM内核32位处理器STM32作为主体芯片完成CAN转USB模块的设计。该模块速度快、可靠性高,能够满足大部分场合的要求。     

基于VC++的数据采集系统设计与实现

基于VS2010平台利用VC++开发了一套适用于RS232、USB、TCP/IP协议通信接口的数据采集系统。该系统实现了监控计算机与嵌入式仪表设备的通信,满足了不同种类传感器的数据采集和处理。并通过实验验证了系统软件的稳定性。     

串口通讯在水泥企业的应用

利用串口通讯功能可实现计算机对现场数据采集、自动控制等功能,因此水泥企业自动化控制系统中串口通讯比较普及。常用到的串口通讯模式有两种：RS232和RS485,因后者是两线制,传输距离长,支持总线形式通讯（1:N）,因此应用范围更广。     

一种小型取样分析控制系统的设计与实现

在低浓度涉氢(及同位素)被污退役核设施的清洗过程中,用质谱分析清洗后气体样本已经无法被准确测量.因此,提出将气态样本转换为液态样本,用液闪谱仪做定量分析的方法,并且建立了模拟实验装置.根据工艺流程的具体要求,设计基于PLC的取样分析控制系统,该控制系统包括常规信号采集、温度PID控制,串口 RS232、RS485通信及...     

计算机串行通信接口的结构及其故障排除

串行通信是计算机之间，计算机与仪器仪表和其它电子装置之间最常用的一种通信方式。其接口标准RS－232C已为国际公认。本文对目前常用的几种串行通信接口的电路结构进行分析，并根据笔者应用、维修RS—232C接口的经验，给出了几种常见故障的分析与排除方法。     

基于AT89S52和SJA1000的CAN-232智能通信模块软硬件设计及实现

本文理论结合实际,依据RS232串行通信标准、CAN2.0技术规范,由浅入深的论述了基于AT89S52和SJA1000的CAN-232智能通信模块的软硬件设计及实现。给出了整体设计思路、软件流程以及软件初始化程序。并结合实际测试中出现的问题对设计中存在的优缺点以及应用前景做了介绍。     

基于LabVIEW的航电开关测试系统设计

设计了航电开关测试系统的信号处理电路和测控软件。通过采集电路对开关两端的电压信号进行采集,将采集到的信号经由中间处理电路的放大、隔离等处理后,通过RS232串口通信线在LabVIEW测控软件界面上进行实时显示。     

S7-200 PLC与称重仪的多机串口通信系统

介绍了以S7-200 PLC作主站,PT650D称重仪作从站的RS485多机串口通信系统的网络构成,分析PT650D的通信操作模式和读、写数据协议帧格式,并据此给出了采用轮询方式设计通信系统的软件实现方法。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。