Effects of design parameters on performance and cost analysis of combined ultraviolet-biofilter systems treating gaseous chlorobenzene based on mathematical modeling

A conceptual mathematical model was used to evaluate the design parameters of a combined ultraviolet (UV)-biofilter system, and perform a cost analysis. Results showed that the UV light source strength and the gas residence times in the UV system (UVRT) and biofilter (EBRT) had positive effects on the overall chlorobenzene removal efficiency of the system. High ratio of UVRT to EBRT improved the removal efficiency, suggesting that the UV system has a greater effect on the overall performance of the system compared with the biofilter. Analysis of the capital and operating costs showed that the capital costs of the standalone biofilter system were much higher than those of the standalone UV system. However, the biofilter operating costs were lower than those of the UV system. The operating costs of the combined UV-biofilter system increased with increasing UVRT/EBRT ratio, whereas its capital costs decreased.     

基于模糊神经网络的A2/O工艺出水氨氮在线预测模型

采用厌氧/缺氧/好氧污水处理系统(A2/O)对人工合成污水进行处理,并利用人工神经网络(ANN)模型和自适应模糊人工神经网络(ANFIS)模型对A2/O处理污水的过程进行仿真模拟.在MATLAB环境下,选取可在线监测的水力停留时间(HRT)、进水pH值(pH)、好氧池溶解氧(DO)和混合液回流比(r)作为输入参量,系统出水氨氮浓度(NH4+eff)为输出量,建立在线预测模型.结合自适应模糊C均值聚类算法,确定ANFIS模型的模糊规则数及最优运行参数,对实验数据进行仿真预测.结果表明,与ANN模型相比,ANFIS模型的仿真输出值与实际值的拟合程度更高,相对误差在6.45%之内,平均绝对百分比误差(MAPE)为2.8%,均方根误差(RMSE)为0.1209,相关系数(R)达0.9956.模型训练过程中所得到的三维曲面图,可直观的反映各因素与出水氨氮浓度之间的非线性函数关系,为A2/O系统的高效稳定运行提供指导.     

Dynamic numerical simulation of coal mine fire for escape capsule installation

Fire in mine laneway leads to disordered ventilation system airflow, and smoke will result in staff poisoning. In such situation, it necessitates to install a rescue capsule in the common staff area. In this paper, the software Fluent was used to simulate the airflow conditions dynamically in No. 5 belt roadway of Kongzhuang Coal Mine when fire broke out. The migration law of CO front was determined. By underground escape experiments, personnel escape velocity model in pathway was established. Based on the numerical simulation and results of field experiments, the escape capsule installation location in the passageway of No. 5 belt roadway was ascertained.     

关于GB25037-2010《工矿靴》标准和HG／T2401—1992标准的探讨

本文主要介绍了GB25037-2010和HG／T2401—1992的区别．并对GB25037-2010提出一些修改意见。     

基于聚类分析的我国火灾空间分布研究

为了解我国火灾事故的空间分布情况,使用系统聚类分析了我国1996 -2010年的火灾统计数据,并结合地理信息系统把分类的结果呈现在相应的区域上进行火灾的空间分布特征研究.聚类分析结果将我国31个省市自治区的火灾事故分为5类,对聚类的结果使用方差分析,类与类之间存在显著差异,说明通过系统聚类得到的分类结果是科学的.进一步分析显示我国火灾事故在空间分布上存在一定的规律性.分析结果可以对了解我国火灾分布特点以及为相关部门提供决策支持.     

石棉相关产品生产过程粉尘危害与控制对策

作为重要的矿产资源,石棉以其良好的性能得到广泛应用。由于石棉开采和石棉相关产品生产过程中产生的石棉粉尘对作业人员身体健康造成严重损害,石棉被列入我国卫生部发布的高毒物品名录。为有效控制石棉粉尘对作业人员的健康危害,在对我国石棉矿山和相关产品生产企业广泛调研基础上,辨识了石棉矿山开采、石棉制品生产过程存在粉尘危害的作业及特点,分析归纳石棉生产加工典型工序的粉尘危害因素。结合我国自然环境、生产技术和管理水平等因素,研究了我国石棉粉尘危害严重的原因,并提出控制石棉尘粉尘职业危害的建议对策,以期为达到降低或消除石棉相关产品生产企业石棉粉尘危害提供参考。     

植被恢复工程对黄河中游土地利用/覆被变化的影响

剧烈的人类活动可快速地改变土地利用/覆被变化（LUCC）格局,并对地表参量和水文要素产生深刻的影响。论文以退耕还林/还草生态工程（Grain for Green Project, GGP）的重点区黄河中游为例,利用5期土地利用数据,定量分析了区域LUCC的过程与趋势,并探讨了GGP对下垫面地表参量及水文要素的影响。结果表明：1）GGP并未显著地改变研究区土地利用空间分布格局,但改变了各土地类型的转换速度和平衡状态。GGP实施前各类型间相互转换频繁,处于动态平衡态势,而 GGP实施后以土地类型单向转换为主,处于不平衡态势,以耕地单向转为林草地为主。2）不同子流域间LUCC存在差异。GGP前汾河流域变化速度较其他区域快,呈准平衡状态;工程实施后的前期,河龙区间与渭河流域的净变化率以及总变化率较快,而后期差异不显著,呈不平衡状态。3）GGP显著地改变了下垫面地表参量和水文要素。GGP的实施使得NDVI、LAI和发射率显著增加,而反照率显著下降,以河龙区间尤为显著;径流系数显著下降,而蒸散发系数显著增加,尤以河龙区间表现显著。     

Composition of stable carbon and nitrogen isotopes in five wetland plants and sediments from the Pearl River estuary,South China

This study sampled five plant species and adjoining sediments from the Qi’ao (Zhuhai) and Nansha (Guangzhou) coastal wetlands located in the Pearl River estuary, South China. The compositions of stable carbon and nitrogen isotopes as well as the content of carbon and nitrogen in the samples were analysed. Differences in carbon/nitrogen (C/N) ratio, and habitat feature were compared between exotic plants (Spartina alterniflora, Sonneratia apetala, and Laguncularia racemosa) and native mangroves (Aegiceras corniculatum and Acrostichum aureum). The results showed that for Qi’ao, which is nearer the sea, the conductivity of the sediments at this location was approximately two times higher than that at Nansha (more inland). The composition of both δ¹³C and δ¹⁵N in sediments was also higher at Qi’ao (?26.52‰ to ?23.83‰ and 6.25‰ to 11.53‰, respectively) as compared to Nansha (?29.30‰ to ?27.43‰ and 3.34‰ to 4.73‰, respectively). Overall, the exotic plants S. alterniflora and S. apetala at Qi’ao and S. apetala and L. racemosa at Nansha had an average δ¹⁵N composition significantly higher than that of the native plants A. corniculatum and A. aureum. This suggests that the three exotic plants employ a different mechanism of δ¹⁵N storage and utilisation as compared to the two native mangrove species, which may result in changes in ecological and biogeochemical processes in these coast wetlands.     

Exploring the possibilities of seaward migrating juvenile European sturgeon Acipenser sturio L., in the Dutch part of the River Rhine

The water quality of the River Rhine has improved and might again suit the critically endangered European sturgeon A. sturio L, which was extirpated from the river by 1950. This study describes the tracking of 43 juvenile hatchery-reared A. sturio, in the Dutch part of the Lower Rhine and Delta, originating from an ex situ measure of the River Gironde population. Observing in situ juvenile downstream migration could help to identify essential habitats and potential threats, before actual stocking. Fish were implanted with transponders of the NEDAP Trail® system and released in two batches, in May (n?=?13) and June 2012 (n?=?30). Detections collected (n?=?26) exhibited no upstream movement. Test-fish moved downstream with the flow. Because the historic estuary is disconnected from the North Sea by a sea lock “Haringvlietdam”, the migration of the fish followed the re-directed river discharge into the Port of Rotterdam (161 km). 96 % (n?=?19) of the detections was collected from the harbor in brackish water, where fish presumably acclimatized to higher salinities. 14 % (n?=?6) of the sturgeons were recaptured in coastal waters by beam trawlers, five within 1 month after release. It is concluded that sustainable coastal fisheries is a key-condition for rehabilitation of the European sturgeon. Adapted management of the sea lock will reconnect the estuary to the North Sea and create more favorable conditions for the species in the Lower Rhine and Delta.     

邻苯二甲酸二(2-乙基己)酯(DEHP)和邻苯二甲酸单乙基己基酯(MEHP)长期暴露对海洋青鳉(Oryzias melastigma)内分泌干扰效应的评价

为探讨邻苯二甲酸二(2-乙基己)酯(DEHP)和邻苯二甲酸单乙基己基酯(MEHP)长期暴露对海水生物的内分泌干扰效应及机制,将孵化后1周的海洋青鳉(Oryzias melastigma)分别暴露于DEHP(0.1 mg·L-1和0.5 mg·L-1)和MEHP(0.1 mg·L-1和0.5 mg·L-1)6个月。结果显示:DEHP显著增加了雌性和雄性海洋青鳉的肝指数,而MEHP只在高剂量时显著增加雄性青鳉的肝指数。对于雌性青鳉,DEHP暴露后肝脏雌激素相关基因ERα、ERβ、ERγ、VTG1、VTG2、ChgH和ChgL的表达水平显著上调,而对于雄性青鳉,DEHP暴露后,只有肝脏ERβ的表达水平显著上调。相比之下,MEHP暴露对雌性和雄性青鳉肝VTG和Chg基因表达无显著影响。DEHP激活了雌性和雄性青鳉的肝过氧化物增殖激活受体PPARα和PPARγ,而MEHP只在低剂量时上调了雄性青鳉PPARγ的表达。在雌性和雄性青鳉体内,VTG和Chg的表达与ERα和ERγ的表达显著相关,并且ER与PPAR也显著相关。研究表明,DEHP长期暴露可通过激活肝性激素受体调控肝雌激素响应基因(VTG和Chg)和过氧化物增殖激活受体(PPARα和PPARγ)的表达而对海洋青鳉产生内分泌干扰效应,并且显示出性别特异性。MEHP对海洋青鳉的内分泌干扰效应弱于DEHP。