山东红日400 kt/a硫酸装置控制室二氧化碳灭火系统设计

随着科学技术的发展,DCS广泛应用于硫酸装置控制室,这就要求在控制室设置灭火系统,而二氧化碳灭火系统因其功能完善、自动性能好、工作准确可靠、操作维修方便等特点被广泛用于硫酸装置控制室.     

硫酸生产自动化的现状及仪表选型

介绍目前我国硫酸装置DCS使用的温度、压力、流量、液位、成分分析仪表和调节阀以及相关的DCS系统。论述各种仪表的选型和使用效果,强调国产仪表及DCS系统的技术进步。与国外产品相比,国产仪表和DCS系统在价格和服务上具有一定的优势,具有较好的性价比。     

国产DCS在40kt/a硫酸装置中的应用

分析国产DCS应用于 40kt/a硫酸装置的优越性和可行性 ,介绍系统组配和控制功能。实际应用情况证明 :自动化水平明显提高 ,维修工作量大大减少 ,装置运行稳定可靠     

硝基苯生产装置中DCS控制系统的应用

介绍了由苯经硝酸和硫酸混合硝化生产硝基苯的工艺过程。根据工艺要求,讨论了现场仪表的选型,包括温度测量仪表、流量测量仪表、液位测量仪表以及调节阀。采用ECS-100系统对硝基苯生产装置进行集散控制,上位机监控软件选用Advan Trol 2.65。介绍了DCS系统的设置,包括进DCS系统的239个I/O点的分类、控制柜卡件配置、控制模块设置,以及紧急停车(ESD)系统和联锁系统的设置。DCS系统的应用取得了良好的效果,生产控制平稳、产品质量合格、装置效能提高。     

JX-300XP DCS在硫磺制酸装置中的应用

介绍了河北建新化工股份有限公司100 kt/a硫磺制酸配套10 kt/a液体SO3装置工艺流程,以及JX-300XP DCS系统应用情况。DCS系统的基本组成包括工程师站(ES)、操作站(OS)、控制站(CS)和通讯网络SCnetⅡ。硫酸装置DCS系统自投运以来,无故障发生,运行良好、控制准确、可靠、操作简单、维护方便,达到了自动化控制的要求。     

硫酸生产系统大联锁优化改进实践

分析了硫精矿制酸系统中关键装置异常运行时存在的安全环保风险以及对后续工序的危害,通过对现用联锁系统的现场实际运行情况了解和电气控制技术分析,找出硫酸生产系统大联锁存在的设计缺陷和技术漏洞,最终在DCS控制系统的配合下对硫酸大联锁控制进行优化改进,既完善了硫酸大联锁系统的防护功能,又提高了生产装置运行的安全性和可靠性,避免了生产系统出现大范围的设备故障和对周边环境的严重污染,同时也保障了硫酸生产系统运行的连续稳定,降低生产成本,增加了一定的社会效益和经济效益。     

硫酸生产过程中基于InTouch和InControl的炉温控制系统研究

给出硫酸生产过程DCS系统的控制方案和硬件配置。通过对基于InTouch和InControl的炉温控制系统的实验研究,探究了硫酸生产过程DCS系统的可行性,结果表明:炉温控制系统运行稳定、可靠,温度控制快速、准确,对实现硫酸生产过程DCS系统具有一定的参考价值。     

磷酸二铵装置降成本技术改造

为了降低磷酸二铵生产成本,对生产工艺进行改进。通过添加热电装置副产硫酸铵替代部分硫酸用于调节产品养分含量、利用渣场池水替代工艺水和硫酸用作尾气洗涤系统的补水、采用分布式计算机控制系统（DCS）精确控制着色剂添加量等措施,磷酸二铵生产成本大幅度下降,预计可节约2 303.3万元/a,吨产品成本下降57.58元,提高了公司磷酸二铵产品的市场竞争能力。     

硫酸装置汽包三冲量控制系统的DCS设计

介绍硫酸装置汽包三冲量控制的DCS设计方案,重点阐述用横河CENTUM-CS DCS的性能优势完成三冲量控制的问题,并详细介绍DCS的设计分析、硬件配置和组态方法。     

降低成品酸质损自动控制技术改造实践

<正>云南铜业股份有限公司冶炼加工总厂(以下简称云铜冶炼总厂)硫酸分厂现有2套制酸装置,分别是Ⅲ,Ⅳ硫酸系列。2套装置均采用二转二吸制酸工艺。干吸工序生产的成品酸浓度检测合格并达到一定液位后,自动溢流至地下计量槽计量,再用酸泵送至酸库保存待售。在干吸酸循环槽设有浓度检测装置,硫酸浓度在DCS系统上实时连续显示,但地下计量槽未设浓度检测装置。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

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.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。