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1.
为了使传统煤矿监控系统传感层有线总线通信节点容量少、布线成本高和通信距离短等问题得到解决,本文设计了基于LoRa技术的无线通信系统,从而全覆盖监控区域的网络。本文对系统的软硬件进行分析并测试。通过现场实验,该系统设计组网灵活,并且具有较高的链接可靠性,通信距离比较远,使煤矿井下传感层无线通信需求得到满足。  相似文献   

2.
根据日常生产中的数据传输要求,介绍了基于多项目链接软件、OPC架构、Modbus通信协议和远程I/O的解决方案,以进行不同生产装置间的实时生产数据互传。实际生产中在进行数据传输设计时,通信方式需要根据现场实际的硬件情况、DCS系统类型及生产需求等进行选择。  相似文献   

3.
魏立  毛丽娟 《中国水泥》2013,(6):102-104
随着工业控制及工厂生产管理的需求,越来越多的大型水泥集团将分布在各地的工厂或者设备集中到总部进行监控与管理。本文以西门子DCS系统DataMonitor为例,讲述了水泥工厂远程专家诊断与维护系统的建立与使用的过程。  相似文献   

4.
通过设计,将天然气集输站内各自动化设备,DCS系统,及基于B_S网络架构的网络发布系统进行融合,可以将现场自动化设备的实时数据,发布于互联网,并通过互联网对现场自动化设备进行操控,以实现远程交互式监控,实现"智慧"管理的概念。  相似文献   

5.
李颀  边青 《化工自动化及仪表》2012,39(9):1181-1183,1229
针对传统有线设备在煤矿井下通信困难的问题,设计了一款基于PXA322的WiFi手持终端。该设备在以PXA322为处理器的核心板的基础上,设计WiFi模块实现无线数据的采集与传输,该手持终端包括电源模块、通信模块及存储显示模块等,通过可编程电源电路和天线阻抗匹配电路的设计降低功耗。实验结果表明:该设计提高了手持设备的信息获取能力,处理速度快,完全能满足煤矿井下无线通信的需求。  相似文献   

6.
现代工业设备已经呈现数字化、网络化和自动化,现场的总线技术可以节约费用,使得操作变的灵活等,所以现在已经成为了公认的发展方向,所以对于DCS接口卡的远程进行修改,使得现场符合HART协议的智能仪表单位、量程等,本文主要分析HART协议的特点和HART协议在DCS接口卡设计上的应用。  相似文献   

7.
根据某化工厂多台加热炉项目控制系统的特点和要求,设计了多台加热炉S7-300 PLC与DCS之间的工业以太网通信系统,通过TCP/IP协议实现各PLC所需与DCS通信数据的汇总,只用一个Modbus RTU接口与DCS互连,完成多台PLC与DCS之间的数据通信,并介绍了相应的硬件设计和软件编程。实际应用表明:由工业以太网和Modbus构成的通信系统具有成本相对低廉以及可靠性高等特点。  相似文献   

8.
基于CDMA/GPRS/RADIO技术的无线环境监控终端设计   总被引:11,自引:4,他引:7  
针对传统环境监测系统不能实现跨通信平台、无线远程数据传输和控制,本文设计了以AVR AT-mega128为核心部件,采用μC/OS-Ⅱ嵌入式实时操作系统的无线环境监控终端.该终端与环境监控中心通过CDMA/GPRS/RADIO无线通信平台进行数据双向传输,突破了传统环境监控系统受地域范围的限制,实现了对环境的远程化、网络化、无人化监控.现场应用结果表明所设计的无线环境监控终端运行稳定,性能可靠.  相似文献   

9.
王伟强  袁纪武  于学春 《广州化工》2012,40(18):172-174
针对石油化工企业生产过程中对装置设备实时监控的需求,设计一种基于Web应用的三层B/S架构的实时监控系统。该系统依托现有的DCS系统和AspenTech InfoPlus.21实时数据库,实现对生产装置及设备运行状态的远程实时监控,使生产过程更加的安全、平稳、高效。  相似文献   

10.
为利用GIS对天然气配气站DCS采集数据进行统一动态监控和可视化管理,本文采用COM、网络通信与数据库技术实现了管网GIS与DCS的有效集成。通过设计集成系统的总体结构模型与功能模块,以及无缝集成DCS与GIS数据库,实现了采集数据远程监控与查询统计、爆管分析和三维显示等功能。实践证明,该系统能够实时获取各配气站计量数据,并为生产、调度和管理提供数据与技术支持。  相似文献   

11.
陆泉芳  俞洁  杨彩玲  李敏睿 《化工学报》2018,69(6):2664-2671
用辉光放电电解(GDE)技术对模拟染料废水阳离子桃红FG的降解过程进行了研究。通过发射光谱法测定了GDE产生的活性粒子,用紫外光谱和总有机碳(TOC)分析仪研究了不同放电时间下的脱色率和去除率,用电导率仪和酸度计测定了降解过程中溶液的电导率和pH的变化,同时用离子色谱对降解中间产物进行了分析。结合各种分析结果,探讨了GDE降解阳离子桃红FG的机理。结果表明,在最佳电压600 V时,溶液中产生HO·、O·、H·等高活性粒子;放电120 min时,200 ml 20 mg/L阳离子桃红FG的脱色率和TOC去除率分别可达99.0%和72.6%;降解液pH先减小后增大,电导率存在先增大后减小的趋势;离子色谱测试表明,降解过程中产生多种有机小分子酸。羟基自由基(HO·)对阳离子桃红FG的降解起关键作用,GDE降解阳离子桃红FG的机理为:HO·作用下助色基团键断裂,产生酚类等中间产物,然后继续被降解为醌和小分子有机酸,最终矿化为Cl-、NO3-、CO2和H2O。  相似文献   

12.
Strong and durable adhesive bonds may be made between polytetrafluoroethylene (PTFE) and either cyanoacrylate (CA) or epoxy adhesives, if the PTFE surface is modified by the use of a “primer” such as triphenylphosphine (TPP) or diaminodiphenylmethane (DDM). The primer mixes with the PTFE surface, and the modified surface is then capable of forming an interphase, tens to hundreds of nanometers thick, where interpenetration of the adhesive and adherend occurs. Using CA adhesives, PTFE/CA/PTFE block compression shear bond strength (ASTM D4501-85) of over 10 MPa can be achieved, with failure occurring cohesively. Initial work with epoxy adhesives indicates that the use of DDM primer gives adhesive bonds comparable in strength with those produced by modification of the fluoropolymer surface by sodium naphthalenide.  相似文献   

13.
苯酚/丙酮市场供需现状与展望   总被引:5,自引:0,他引:5  
刘媛  闵剑 《当代石油石化》2004,12(4):24-27,44
分析了世界和我国苯酚/丙酮供需现状及消费结构,对未来供需进行了预测,提出了发展我国苯酚/丙酮装置的具体建议。  相似文献   

14.
To understand and characterize the pathogenic mechanisms of inflammatory bowel disease, dextran sulfate sodium (DSS) has been used to induce acute and chronic colitis in animal models by causing intestinal epithelium damage. The mechanism of action of DSS in producing this outcome is not well understood. In an effort to understand how DSS might impact epithelial cell metabolism, we studied the intestinal epithelial cell line Caco-2 incubated with 1% DSS over 56 hours using (1)H NMR spectroscopy. We observed no difference in cell viability as compared to control cultures, and an approximately 1.5-fold increase in IL-6 production upon incubation with 1% DSS. The effect on Caco-2 cell metabolism as measured through changes in the concentration of metabolites in the cell supernatant included a three-fold decrease in the concentration of alanine. Given that the concentrations of other amino acids in the cell culture supernatant were not different between treated and control cultures over 56 hours suggest that DSS inhibits alanine synthesis, specifically alanine aminotransferase, without affecting other key metabolic pathways. The importance of alanine aminotransferase in inflammatory bowel disease is discussed.  相似文献   

15.
Cannabidiol (CBD), a nonpsychoactive phytocannabinoid, has recently emerged as a potential cytotoxic agent in addition to its ameliorative activity in chemotherapy-associated side effects. In this work, the potential interactions of CBD with docetaxel (DOC), doxorubicin (DOX), paclitaxel (PTX), vinorelbine (VIN), and 7-ethyl-10-hydroxycamptothecin (SN−38) were explored in MCF7 breast adenocarcinoma cells using different synergy quantification models. The apoptotic profiles of MCF7 cells after the treatments were assessed via flow cytometry. The molecular mechanisms of CBD and the most promising combinations were investigated via label-free quantification proteomics. A strong synergy was observed across all synergy models at different molar ratios of CBD in combination with SN−38 and VIN. Intriguingly, synergy was observed for CBD with all chemotherapeutic drugs at a molar ratio of 636:1 in almost all synergy models. However, discording synergy trends warranted the validation of the selected combinations against different models. Enhanced apoptosis was observed for all synergistic CBD combinations compared to monotherapies or negative controls. A shotgun proteomics study highlighted 121 dysregulated proteins in CBD-treated MCF7 cells compared to the negative controls. We reported the inhibition of topoisomerase II β and α, cullin 1, V-type proton ATPase, and CDK-6 in CBD-treated MCF7 cells for the first time as additional cytotoxic mechanisms of CBD, alongside sabotaged energy production and reduced mitochondrial translation. We observed 91 significantly dysregulated proteins in MCF7 cells treated with the synergistic combination of CBD with SN−38 (CSN−38), compared to the monotherapies. Regulation of telomerase, cell cycle, topoisomerase I, EGFR1, protein metabolism, TP53 regulation of DNA repair, death receptor signalling, and RHO GTPase signalling pathways contributed to the proteome-wide synergistic molecular mechanisms of CSN−38. In conclusion, we identified significant synergistic interactions between CBD and the five important chemotherapeutic drugs and the key molecular pathways of CBD and its synergistic combination with SN−38 in MCF7 cells. Further in vivo and clinical studies are warranted to evaluate the implementation of CBD-based synergistic adjuvant therapies for breast cancer.  相似文献   

16.
关于科研开发效率的思考   总被引:1,自引:0,他引:1  
作者从认识论和方法论的角度出发,对提高科研开发效率提出如下看法:1.当代的经济竞争,实质是科技产业化能力的竞争。2.研究开发应是从投入到产出的完整系统。3.产业部门的研究开发要面向市场。4.只有充分利用专利保护,才能在国际竞争中赢得主动。5.要保持竞争优势,须把信息工作提到新水平。  相似文献   

17.
阿尔兹海默病(老年性痴呆,AD)是由β淀粉样蛋白(Aβ)和微管相关蛋白(Tau)聚集形成的具有毒性作用的寡聚物而引起的老年人主要以记忆力下降和脑部形成老年斑、神经纤维缠绕为特征的神经退行性疾病. 小胶质细胞作为中枢神经系统中的固有免疫细胞,是脑内免疫监视的关键成分,发挥内源性免疫防御作用. 正常生理状态的小胶质细胞能有效吞噬和清除毒性Aβ寡聚体,阻止AD发生. 在AD病理过程中,过度激活的小胶质细胞通过补体依赖途径过度吞噬突触,导致突触丧失,同时大量释放炎症因子,促进Tau相关病理变化,对神经元造成直接损伤,导致认知功能下降. 由此可见,小胶质细胞在AD发生发展过程中起着双刃剑的作用,探明小胶质细胞的极化状态及其在AD疾病机理中的作用将为攻克AD的药物研发提供突破性思路.  相似文献   

18.
This paper investigates the water molecule from a variety of viewpoints. Water can involve different isotopes of Hydrogen and Oxygen, it can form differently shaped isomer molecules, and, when frozen, it occupies space differently than most other substances do. The tool for conducting the investigation of all this is called 'Algebraic Chemistry'. This tool is a quantitative model for predicting the energy budget for all sorts of changes between different ionization states of atoms that are involved in chemical reactions and in changes of physical state. The model is based on consistent patterns seen in empirical data about ionization potentials, together with rational scaling laws that can interpolate and extrapolate for situations where no data are available. The results of the investigation of the water molecule include comments, both positive and negative, about technologies involving heavy water, poly water, Brown's gas, and cold fusion.  相似文献   

19.
Dopamine (DA) is an important signal mediator in the brain as well as in the periphery. The term “dopamine homeostasis” occasionally found in the literature refers to the fact that abnormal DA levels can be associated with a variety of neuropsychiatric disorders. An analysis of the negative feedback inhibition of tyrosine hydroxylase (TH) by DA indicates, with support from the experimental data, that the TH-DA negative feedback loop has developed to exhibit 3,4-dihydroxyphenylalanine (DOPA) homeostasis by using DA as a derepression regulator. DA levels generally decline when DOPA is removed, for example, by increased oxidative stress. Robust DOPA regulation by DA further implies that maximum vesicular DA levels are established, which appear necessary for a reliable translation of neural activity into a corresponding chemical transmitter signal. An uncontrolled continuous rise (windup) in DA occurs when Levodopa treatment exceeds a critical dose. Increased oxidative stress leads to the successive breakdown of DOPA homeostasis and to a corresponding reduction in DA levels. To keep DOPA regulation robust, the vesicular DA loading requires close to zero-order kinetics combined with a sufficiently high compensatory flux provided by TH. The protection of DOPA and DA due to a channeling complex is discussed.  相似文献   

20.
通过脱醇法在凹凸棒土(ATP)表面接枝γ-氨丙基三乙氧基硅烷(APTES)实现氨基化(ATP-APTES),再经酰胺化反应接枝α-溴代异丁酰溴,从而在ATP表面固载ATRP引发基团(ATP-Br);最后以2,2-偶氮二异丁腈(AIBN)和ATP-Br为双组分引发体系进行正反向同时引发原子转移自由基聚合(SR&NI ATRP)制备ATP接枝聚苯乙烯杂化粒子(ATP@PS)。结果表明AIBN结合ATP-Br引发体系进行SR&NI ATRP具有活性/可控聚合的特征,随催化剂用量增大,体系过早偏离一级动力学行为。聚合温度在80℃,投料比为单体/催化剂/AIBN/ATP-Br=200/0.3/0.05/0.5的条件下,接枝聚合物和游离聚合物分子量差异随转化率(c)增大逐渐增加,转化率为31.1%时,两者分子量分布(PDI)均保持在1.54以下,ATP-Br表面ATRP引发基团的引发效率为6.3%。杂化粒子在PS基体中分散得到明显改善。  相似文献   

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