基于数值模拟的细水雾在汽车涂装车间喷漆室的应用研究

采用FDS软件对细水雾扑救汽车涂装车间喷漆室火灾的灭火效能进行数值模拟分析,着重探讨了喷漆室纵向通风、细水雾雾滴粒径、雾滴喷射速度、汽车障碍物等对扑灭油漆火的影响。模拟结果表明:在细水雾与油漆火的相互作用过程中,细水雾对火源的表面冷却和隔氧窒息作用显著;为了防止室内氧气得到补充,在开启细水雾灭火的同时应当联动控制关闭纵向通风系统;在模拟工况条件下雾滴粒径为100μm~300μm的细水雾灭火效果优于粒径为400μm、500μm的细水雾;雾滴在一定喷射速度范围内速度越大灭火效果越好,喷射速度为10m/s的雾滴灭火效果明显优于3m/s和5m/s的雾滴,但是为了防止火焰横向蔓延,喷射速度不宜过高;在汽车障碍物火灾中部分微小的细水雾雾滴受到火焰的卷吸作用,可以绕过障碍物进入火区发挥冷却作用,细水雾灭火系统能够有效控制障碍物火灾,可以应用于汽车涂装车间喷漆室。     

二次加压泵房的噪声污染及控制

对某居民区内供水泵房产生的噪声污染进行测量分析评价 ,并结合实际提出控制泵房内给水系统噪声产生与传播的具体措施     

场地土壤中有效态砷的稳定化处理及机理研究

分别以生石灰和亚铁盐作为辅助剂与稳定剂对2种砷污染的土壤进行稳定化处理,通过化学浸出、形态及结构研究,揭示土壤中有效砷的稳定效率和机理.结果表明,外源铁添加量与土壤砷含量(Fe/As)的物质的量比达到6:1~8:1,CaO投加比例为0.05%~0.1%(w/w)时,土壤中有效态砷的稳定效率超过85%.土壤有效砷的稳定化处理主要是将砷从非专性吸附态和专性吸附态转化为弱结晶的铁铝或铁锰水化氧化物结合态、结晶铁铝或铁锰水化氧化物结合态.稳定处理后2种污染土均有新物相羟砷铜矿(As2Cu5H4O12)生成.     

纳米金颗粒进入梨形四膜虫体内的方式及其分布

以梨形四膜虫为模式动物,研究水体中的纳米金颗粒进入生物体的方式、分布及其生物学效应.实验中所采用的纳米金颗粒平均粒径为13 nm,分散均匀.透射电镜结果表明,纳米金颗粒可以通过口沟（进食）和细胞膜（内吞）两种方式进入梨形四膜虫体内;纳米金颗粒进入梨形四膜虫体内后,主要分布在食物泡中,另外细胞质和细胞核（大核）中也含有少量的纳米金颗粒.同时,研究表明在实验所用的浓度范围内,纳米金颗粒对梨形四膜虫无明显毒性.     

Application and mechanism of polysaccharide extracted from Enteromorpha to remove nano-ZnO and humic acid in coagulation process

Green source Ep was extracted from marine alga waste. The molecule model structure of Ep was studied and constructed. PAC-Ep coagulation system improves the efficiency of removal efficiency. Synergistic effects between NPs and HA make a big difference to enhance efficiency. Mechanism is charge neutralization, hydrogen bonding and adsorbing-complexing Enteromorpha polysaccharide (Ep) extracted from alga a novel green coagulant aid for nanoparticles (NPs) and heavy metal ions removal and the structure of EP was intensively studied in this study. The integration of Ep with polyaluminum chloride (PAC-Ep) coagulants exhibited higher coagulation performance than that of the polyaluminum chloride (PAC) because of the negatively charged NPs suspension and humic aid (HA) solution. Significant high removal efficiencies of dissolved organic matter (94.1%), turbidity (99.3%) and Zn ions (69.3%) were achieved by the PAC-Ep coagulants. The dual-coagulation properties of PAC-Ep for different pollutants was based on multiple mechanisms, including (i) Al³⁺ charge neutralization; (ii) hydroxy aluminum hydroxyl bridging formed polynuclearhydroxy complexes bridge and sweep colloidal particles; (iii) adsorption and bridging of Ep chain for the NPs and heavy metal ions. Results indicated that the destabilization of colloid was induced by the coexisting HA and higher removal was achieved as ions adsorption was enhance in the presence of HA complexation. On the basis of that, the extraction of polysaccharide is a promising candidate for its high coagulation performance in water treatment.     

卡源故障下悬挂链式辐照室火灾危险性研究

为了分析悬挂链式辐照室的火灾危险性,采用实验测定得出室内典型辐照物品的点着温度,通过设置3组火灾场景模拟得到卡源故障下各火灾场景辐照室内温度变化曲线。结果表明:各火灾场景卡源初期1 h,温度上升速度较快。随着时间的增长,室内温度不断上升,但上升速率逐渐放缓。在火灾场景A,B,C等3组条件下卡源故障分别发生9,4,2.4 d后,室内局部温度能达到210℃,室内辐照物品有可能被引燃。     

An Observation Method for Analyzing Operators’ Routine Activity in Computerized Control Rooms

An activity analysis method was developed for studying the structure and dynamics of control room operators’ activity during normal operation based on directly observable elements of the operators’ behavior. The method assesses current activity along three dimensions in each 5-min period of the shift. Intensity characterizes arousal level, direction shows whether the activity is directed predominantly at the process control task, at something else, or miscellaneous. Motivation reflects if the activity is driven by intrinsic or extrinsic motivation. A case study is presented, in which 3 morning, 3 afternoon, and 3 night shifts of a Nuclear Power Plant operator crew are involved. The obtained results gave a deeper understanding of the operators’ activity and also revealed an “arousal compensation” tendency.     

Ag3PO4掺杂g-C3N4催化剂的制备及其可见光催化降解含碘类造影剂性能

以沉淀-回流方法于磷酸银(Ag₃PO₄)中掺杂氮化碳(g-C₃N₄)制备新型复合光催化剂,同时采用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射图(XRD)等手段对合成催化剂的形态特征、晶型结构以及物理化学性质进行表征.以碘帕醇(IPM)作为目标污染物,通过改变催化剂的使用条件考察了氙灯光照下催化剂对水溶液中含碘类造影剂(ICMs)的光催化降解性能,并且分析了催化氧化过程中可能的污染物降解途径以及转化产物.结果表明,合成后的催化剂结构稳定,相对于使用单一催化剂(Ag₃PO₄或g-C₃N₄)条件下,复合催化剂对ICMs的光降解性能都得到大幅度提升,经条件优化后,确定Ag₃PO₄与g-C₃N₄的质量比例为0.15∶0.1时降解效果最佳,但不可超过0.2∶0.1,且降解性能与催化剂的投加浓度呈正相关,浓度在0.75 ...     

室温低氨氮基质单级自养脱氮颗粒污泥启动效能与污泥特性

室温低氨氮基质条件下单级自养脱氮工艺的启动和稳定运行是该工艺应用于市政污水处理的前提和基础.本研究在气升式反应器中接种久置的PN/A(partial nitritation and ANAMMOX)颗粒污泥,控制温度在(23±2)℃,pH在7. 7～8. 0,以氨氮浓度为70 mg·L~(-1)的人工无机配水为基质,考察单级部分亚硝化-厌氧氨氧化实现室温启动效能.通过逐级缩短HRT(1. 1 h→0. 9 h→0. 7 h→0. 5 h)提升氮负荷[1. 53 kg·(m~3·d)~(-1)→1. 87 kg·(m~3·d)~(-1)→2. 40 kg·(m~3·d)~(-1)→3. 36kg·(m~3·d)~(-1)],逐步恢复AOB、AMX菌活性以及微生物协同效能.经过95 d运行调控,反应器成功启动,NH_4~+-N和TN去除率达85%和69%.根据各阶段污泥性能,严格控制溶解氧,有效抑制NOB.污泥适应环境后,颗粒粒径随负荷提升逐渐增大,最终平均粒径达1. 30 mm.成熟的自养颗粒污泥轮廓光滑清晰,扫描电镜显示,颗粒污泥内部形成空腔,表面有孔隙,污泥形态以球菌为主,并有少量杆菌及短杆菌. EPS主要成分为蛋白质(81. 48%),泥水分离效果较好.