临安市大气中二氧化硫污染现状及环境容量测算研究

根据2011年-2015年的监测数据分析了临安市大气中二氧化硫污染现状,并利用"A值法"测算大气中二氧化硫的最大环境容量.结果表明,能源消耗中,原煤占60%以上;大气中二氧化硫日均浓度范围为0~73μg/m3,年均排放量呈现下降趋势;1月份和12月份二氧化硫的浓度较高,7月份和8月份浓度较低.全市二氧化硫环境容量为12.21万吨,城区环境容量为2.96万吨.     

温度对海洋厌氧氨氧化菌脱氮效能的影响

采用ASBR反应器,研究了不同温度对海洋厌氧氨氧化菌处理含海水污水脱氮效能的影响,并利用修正的Logistic模型模拟不同温度下海洋厌氧氨氧化菌的动力学特性.结果表明,在25~35℃之间,温度对反应器的脱氮效能影响不大,总氮去除率(TNRE)基本保持在(82±2)%,总氮容积负荷去除速率(TNRR)稳定在(0.62±0.01)kg·(m~3·d)~(-1);在20℃时,TNRE从起始的59%经过13d上升到79%,说明在此温度下,海洋厌氧氨氧化菌仍然具有较强的脱氮能力,反应器在较低温处理含海水污水具有较好的发挥潜能;然而当温度降到15℃和10℃时,反应器的脱氮效能受到明显的抑制,TNRE分别下降至(40±8)%和(11±4)%,TNRR也下降至(0.30±0.04)kg·(m~3·d)~(-1)和(0.08±0.03)kg·(m~3·d)~(-1).根据Arrhenius方程得到,在25~35℃时,海洋厌氧氨氧化反应的活化能为26 k J·mol~(-1),在10~25℃时,海洋厌氧氨氧化反应的活化能为76 k J·mol~(-1).此外,通过Logistic模型对海洋厌氧氨氧化脱氮进行动力学分析,得到不同温度下NRE和出水总氮浓度(ceff)的预测公式,相关系数R2在0.966 8~0.995 7之间.     

湿式镁法烟气脱硫副产物MgSO4热解回收MgO

通过对MgSO4的热解研究为湿式镁法烟气脱硫副产物的综合利用探索适宜的热解条件.实验结果表明,在升温速率为20 ℃/min、热解温度为850℃、恒温时间为2.0 h的条件下,由无水MgSO4热解制得的MgO收率高达99.8％.由MgSO4·7H2O热解制得的MgO收率仅为72.1％.由此表明,干燥的MgSO4对热解更有利.     

Occurrence, profiles, and ecotoxicity of poly- and perfluoroalkyl substances and their alternatives in global apex predators: A critical review

Certain poly- and perfluoroalkyl substances (PFASs) exhibit significant bioaccumulation/biomagnification behaviors in ecosystems. PFASs, such as perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexanesulfonic acid (PFHxS) and related precursors, have elicited attention from both public and national regulatory agencies, which has resulted in worldwide restrictions on their production and use. Apex predators occupy the top trophic positions in ecosystems and are most affected by the biomagnification behavior of PFASs. Meanwhile, the long lifespans of apex predators also lead to the high body burden of PFASs. The high body burden of PFASs might be linked to adverse health effects and even pose a potential threat to their reproduction. As seen in previous reviews of PFASs, knowledge is lacking between the current stage of the PFAS body burden and related effects in apex predators. This review summarized PFAS occurrence in global apex predators, including information on the geographic distribution, levels, profiles, and tissue distribution, and discussed the trophic transfer and ecotoxicity of PFASs. In the case where legacy PFASs were restricted under international convention, the occurrence of novel PFASs, such as 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA) and perfluoroethylcyclohexane sulfonate (PFECHS), in apex predators arose as an emerging issue. Future studies should develop an effective analytical method and focus on the toxicity and trophic transfer behavior of novel PFASs.     

Metaphyseal chondrodysplasia McKusick type in a Chinese fetus,caused by novel compound heterozygosity 64T> A and 79G >T in RMRPgene

We present the first confirmed case by molecular analysis of a metaphyseal chondrodysplasia, McKusick type, in a 22-week fetus. Two novel compound heterozygous mutations, 64T> A and 79G > T, were found in the highly conserved regions of the RMRP gene. Twenty-two heterozygous g.1018 T> C mutations, two homozygous g.1018 T> C mutations, two heterozygous insertion mutations g.799_g.800insC and one heterozygous insertion mutation g.849_g.850insT were found among 100 normal controls. Careful radiological examination of the fetus for skeletal dysplasia allowed definitive diagnosis, proper genetic counselling and future prenatal diagnosis. Copyright © 2006 John Wiley & Sons, Ltd.     

木质家具行业农民工职业危害预防与教育

近年来,我国经济的蓬勃发展带动了家具行业的迅速发展,家具制造企业数量和从业人员不断增加、企业规模不断扩大。目前我国家具企业数量及从业人数居世界首列,家具企业6万余家、从业人员650余万人。根据《国民经济行业分类与代码》GB/T4754-2002,家具制造业分为木质家具制造、竹藤家     

机动车闯红灯判别模型及评价研究

为了提高机动车闯红灯警示系统判别准确率,提出适用于该系统的机动车闯红灯判别模型并进行评价。首先综述闯红灯警示系统的产生与发展现状,根据系统服务需求与工作流程,提出使用Logistic回归与神经网络方法建立判别模型预测机动车停止-通过行为,通过城市交通实测数据对模型进行评价。数据采集自上海城市道路交叉口进口道,通过Autoscope视频检测系统提取机动车运行数据。评价结果表明,Logistic回归与神经网络模型正确判别率均达到90%以上,神经网络具有更好的判别准确率。相对于速度,当前检测地点与上游地点30 m处车速差或速度比更宜作为模型中的判别参数。     

城市道路环境中驾驶人应激反应能力研究

为预防驾驶人在城市道路行车时因应激反应失误而引发交通事故,基于动力定型理论,开发驾驶人应激反应训练系统并进行仿真试验研究。试验选用30名被试人员分别在3个城市道路中典型应激交通场景下进行,运用MP150实时记录被试人员的心率参数,运用对数回归和相关性分析,研究应激反应能力与训练次数间的定量关系。研究结果表明,随着训练次数增加,驾驶人应激反应能力增强。驾驶人经过标准规定次数的训练,即可减缓应激状态下的心理紧张,提高应激反应准确性和速度。设计的系统及建立的训练次数标准,满足驾驶人应激反应能力训练需求,可增强驾驶人应激能力,减少此类交通事故发生。     

采用浅水盘加湿方式实现低温高湿应力

目前运用最为广范的加湿方法是利用浅水盘加湿,根据其加湿原理分析,浅水盘加湿方法一般只能控制在常温以上的湿度。本文介绍一种方法,结合湿度原理在不对设备进行改造的情况下实现了低温高湿的试验应力。同时,反应出国外某些先进设备对试验风险的完善考虑。