Impaired behavior and changes in some biochemical markers of bivalve (Ruditapes decussatus) due to zinc toxicity

Susceptibility and response of bivalves, the clam Ruditapes decussatus, to zinc (Zn) were studied by monitoring behavior using valve movement and some biochemical parameters. The LC₅₀ was 4.1 mg L^?1 at 7 days. Depuration of Zn from their tissues was also followed. Accumulation of Zn increased with concentration and duration of exposure. After 20 days, Zn caused impairment of valve movement as well as the antioxidant system, decreasing glutathione and protein levels and increasing the lipid peroxidation which is indicative of oxidative damage. Results suggested that behavior and biochemical parameters of clam R. decussatus were sensitive and suitable responses for assessing the effects of Zn on the aquatic ecosystems. It could be concluded that there is a time–dose–response relationship of Zn with behavior and oxidative stress of R. decussatus.     

大型石化装置安全阀安全保障综合管理体系应用研究

本文研究采用基于风险的完整性综合管理方法解决大型石化企业安A-N管理中存在的问题。阐述了建立安全阀数据库的基本原则，提出根据失效可能性和风险等级制定安全阀分类管理策略，实现分类管理，进行检验组织优化，制定安全阀失效紧急处置指南，以期形成安全阀安全保障综合管理体系，并建立包括网上报检、备阀备件统计管理、风险定量计算等功能的安全阀管理信息系统，在保障安全阀安全运行的同时，提高管理效能，降低管理成本。     

An experimental study of an LPG tank at low filling level heated by a remote wall fire

This paper describes an experimental study of 2300 L pressure vessels exposed to remote fire heating by a natural gas fuelled wall fire simulator. The tanks were filled to 15% capacity with commercial liquid propane. The flame intensity and distance were varied to study the effect of different heating levels on the tank and its lading.The fire simulator is first characterized with tests including fire thermocouples, radiative flux meters and thermal imaging. With the appropriate positioning of a target tank it is possible to get very realistic fire heat fluxes at the tank surface.Three tests were conducted with the 2300 L tanks filled to 15% capacity with propane. The tanks were positioned at three different distances from the wall fire resulting in measured average peak heat flux at the tank surfaces ranging between 24 and 43 kW m^?2. The data shows rapid rise in vapour space wall temperatures, significant temperature stratification in the vapour space, and moderate rate of pressure rise. These results provide excellent data for the validation of computer models used to predict the response of pressure vessels exposed to moderate heating from a remote fire.     

联锁控制阀及其在散料除尘中的应用

介绍一种自行设计，并已实践应用的机械联锁控制阀与电动卸料车、同步开启关闭自动控制技术。它是由控制阀、开启步进器、关闭装置等，与卸料车不可分割的相关组合而成，从而实现了散粒物料的转运卸料与通风除尘联锁同步、协调一致的工作特性。     

真空加氯机及氯气吸收系统的应用

水厂应用真空加氯机代替转子加氯机，并设置氯气吸收系统，消除了 氯对环境的污染和对人体的危害，显著提出了出水余氯合格率。     

气箱脉冲袋式收尘器及其应用

介绍了气箱脉冲袋式收尘器的结构、特点,清灰过程分析以及不同条件下的应用实例。     

小孔板对阀门噪声的控制作用及对阀门流量控制的影响

本实验采用在阀门下游安装小孔板的方法可完全防止阀门噪声向下游传播,使下游噪声仅为小孔板小孔喷注的噪声,比阀门噪声低很多,但小孔板将影响阀门的流量控制作用,本文从理论上提出计算阀门及阀门下游加上孔板后两种情况阀门的开度与流量及驻点压降的关系的方法,特例的数值计算的结果与实验测量符合良好,该法可以可靠地用于工程设计。     

液化石油气罐车卸车作业事故——安全阀意外开启泄压原因调查

为了提高液化石油气罐车采用压缩机卸车法作业的安全性,通过对某液化石油气罐车卸车作业时其顶部安全阀意外开启泄压的事故原因进行调查,查明了导致罐车顶部安全阀意外开启泄压的直接原因是操作工人违章作业导致储罐与罐车罐体内气相液化石油气压差安全裕量严重不足所致。同时探讨了在夏季高温环境采用压缩机法对液化石油气罐车卸车作业时液化石油气罐车顶部安全阀整定值设定、液化石油气储罐与罐车罐体内气相液化石油气压差安全裕量的重要性。     

一种新型沉降离心分离装置自控排液阀的设计

设计了一种新型的自控排液阀,来实现沉降离心分离装置中液体和悬浮物的连续分离和自动排出.从理论上论述了自控阀的工作原理,并对自控阀的可靠性进行了分析.讨论了有关参数对该阀动作的影响.设计的自控排液阀可使悬浮物的分离装置结构简单紧凑,实现高效、可靠的连续作业.     

18CrNi4WA 钢渗碳针阀体开裂失效分析

目的研究18CrNi4WA钢渗碳针阀体开裂失效原因。方法通过化学成分分析、断口扫描分析、金相组织分析、能谱分析等测试手段,对18CrNi4WA钢渗碳针阀体的断裂模式及失效原因进行分析。结果针阀体失效件原始材料符合针阀体制造要求,但渗碳淬火温度过高,未得到最优的渗碳层组织,燃油中存在的硫元素导致喷油孔位置产生严重腐蚀,燃油局部压力的变化导致针阀体表面产生空蚀损伤,裂纹起始于喷油孔圆周面,自裂纹源向外发散呈月牙状,为典型疲劳断裂特征。结论腐蚀与空蚀损伤的协同作用加快裂纹的萌生,使针阀体在热疲劳及机械振动等交变载荷的作用下产生疲劳开裂,使用寿命大为降低。