天然土壤对水溶液中Pb~(2+)的吸附

以天然土壤为吸附材料,处理水溶液中的Pb2+,研究3种土壤对水溶液中Pb2+的吸附过程并结合土壤的理化性质对吸附规律进行初步分析。结果表明,棕壤和钙层土对Pb2+的吸附能力远大于红壤,3种土壤对Pb2+的吸附动力学曲线与二次动力学方程有较好的拟合性;3种土壤吸附Pb2+的吸附等温线用Langmuir方程描述最为合适,其次是Temkin方程,再次是Frenudlich方程,钙层土对Pb2+的吸附受温度影响较为明显;由实验数据得出的反应热力学参数说明3种土壤对Pb2+的吸附是自发的吸热过程;Pb2+在饱和吸附的土壤表面覆盖率并不高;土壤对Pb2+的吸附能力受各种土壤理化性质的综合影响。     

Effect of tetraconazole application on the soil microbial community

Tetraconazole is one of the most commonly used triazole fungicides in agricultural practice, and its continuous application poses a potential risk for non-target soil microorganisms. Therefore, the objective of this study was to evaluate the effect of tetraconazole at the field rate (T1, 0.33 mgkg^?1 of soil), three times the field rate (T3, 1.00 mgkg^?1 of soil) and 10 times the field rate (T10, 3.33 mgkg^?1 of soil) on the soil microorganisms. To ascertain this effect, the tetraconazole concentration and the microbial properties with potential as bioindicators of soil health (i.e. microbial biomass C, basal respiration, substrate-induced respiration, structure diversity and functional community profiling) were determined. The results showed that the degradation half-lives of tetraconazole varied from 69 to 87 days, depending on the three application concentrations. The microbial biomass C, basal respiration and substrate-induced respiration were inhibited, but they tended to recover at the end of the incubation when tetraconazole was applied at the recommended field rate. The ratios of the gram-negative to gram-positive (GN to GP) bacteria decreased, and the fungi to bacteria ratio increased after a temporal decrease on the seventh day. A principal component analysis of the PLFAs showed that tetraconazole application significantly shifted the microbial community structure on day 7. Different functional community profiles were observed, depending on the tetraconazole application rates. It was concluded that tetraconazole application decreases the soil microbial biomass and activity and changes the structures of the soil microbial community.     

Emergy-based comparative analysis on industrial clusters: economic and technological development zone of Shenyang area,China

In China, local governments of many areas prefer to give priority to the development of heavy industrial clusters in pursuit of high value of gross domestic production (GDP) growth to get political achievements, which usually results in higher costs from ecological degradation and environmental pollution. Therefore, effective methods and reasonable evaluation system are urgently needed to evaluate the overall efficiency of industrial clusters. Emergy methods links economic and ecological systems together, which can evaluate the contribution of ecological products and services as well as the load placed on environmental systems. This method has been successfully applied in many case studies of ecosystem but seldom in industrial clusters. This study applied the methodology of emergy analysis to perform the efficiency of industrial clusters through a series of emergy-based indices as well as the proposed indicators. A case study of Shenyang Economic Technological Development Area (SETDA) was investigated to show the emergy method’s practical potential to evaluate industrial clusters to inform environmental policy making. The results of our study showed that the industrial cluster of electric equipment and electronic manufacturing produced the most economic value and had the highest efficiency of energy utilization among the four industrial clusters. However, the sustainability index of the industrial cluster of food and beverage processing was better than the other industrial clusters.     

高压脉冲放电等离子体对水中土霉素的降解

采用针-板式高压脉冲放电等离子体降解水中土霉素,考察了放电输出功率、空气流量、电极间距、溶液初始浓度、初始pH、初始电导率和添加Fe2+的量对土霉素去除率的影响。实验结果表明,高压脉冲放电等离子体对水中土霉素有较好的去除效率,在初始浓度200 mg/L,放电功率64 W,电极间距8 mm,空气流速0.05 m3/h,初始pH为2.6,初始电导率1.083 mS/cm条件下,反应12 min后,土霉素的去除率可达97%。向溶液中添加Fe2+,可提高土霉素的去除率。TOC随着反应时间的延长逐渐减小,反应12 min时,TOC去除率可达57%,说明大分子物质被降解为小分子物质,部分被完全矿化为CO2和H2O。     

Emergy-based assessment on industrial symbiosis: a case of Shenyang Economic and Technological Development Zone

Industrial symbiosis is the sharing of services, utility, and by-product resources among industries. This is usually made in order to add value, reduce costs, and improve the environment, and therefore has been taken as an effective approach for developing an eco-industrial park, improving resource efficiency, and reducing pollutant emission. Most conventional evaluation approaches ignored the contribution of natural ecosystem to the development of industrial symbiosis and cannot reveal the interrelations between economic development and environmental protection, leading to a need of an innovative evaluation method. Under such a circumstance, we present an emergy analysis-based evaluation method by employing a case study at Shenyang Economic and Technological Development Zone (SETDZ). Specific emergy indicators on industrial symbiosis, including emergy savings and emdollar value of total emergy savings, were developed so that the holistic picture of industrial symbiosis can be presented. Research results show that nonrenewable inputs, imported resource inputs, and associated services could be saved by 89.3, 32.51, and 15.7 %, and the ratio of emergy savings to emergy of the total energy used would be about 25.58 %, and the ratio of the emdollar value of total emergy savings to the total gross regional product (GRP) of SETDZ would be 34.38 % through the implementation of industrial symbiosis. In general, research results indicate that industrial symbiosis could effectively reduce material and energy consumption and improve the overall eco-efficiency. Such a method can provide policy insights to industrial park managers so that they can raise appropriate strategies on developing eco-industrial parks. Useful strategies include identifying more potential industrial symbiosis opportunities, optimizing energy structure, increasing industrial efficiency, recovering local ecosystems, and improving public and industrial awareness of eco-industrial park policies.     

基于广义马尔可夫过程的多部件并联可修复系统稳态可用度分析

基于广义马尔可夫过程的可修复系统可用度解析表达式求解较难。因此,值得探索,本文所研究的并联可修复系统由n个同型部件构成,且部件平均故障间隔时间分布服从指数分布,故障后修复时间分布服从一般连续型分布。运用补充变量法,建立基于广义马尔可夫过程的可修复系统可用度计算模型,得到系统的偏微分-积分方程组,经过拉普拉斯变换,得到系统可用度稳态解析表达式。     

海拔对高压电器设备空气间隙放电性能的影响研究

基于大型高海拔环境模拟试验室,通过控制海拔、温度和湿度三个参数,使用带状铜母线和镀锌钢板组成的试验装置,来进行海拔高度对高压电器设备空气间隙放电性能试验研究。通过试验数据分析,总结海拔高度对高压电器设备空气间隙放电性能的影响规律,对高压电器设备制造及相关标准规范制定提供数据支持。     

Optimization of pressure gauge locations for water distribution systems using entropy theory

It is essential to select the optimal pressure gauge location for effective management and maintenance of water distribution systems. This study proposes an objective and quantified standard for selecting the optimal pressure gauge location by defining the pressure change at other nodes as a result of demand change at a specific node using entropy theory. Two cases are considered in terms of demand change: that in which demand at all nodes shows peak load by using a peak factor and that comprising the demand change of the normal distribution whose average is the base demand. The actual pressure change pattern is determined by using the emitter function of EPANET to reflect the pressure that changes practically at each node. The optimal pressure gauge location is determined by prioritizing the node that processes the largest amount of information it gives to (giving entropy) and receives from (receiving entropy) the whole system according to the entropy standard. The suggested model is applied to one virtual and one real pipe network, and the optimal pressure gauge location combination is calculated by implementing the sensitivity analysis based on the study results. These analysis results support the following two conclusions. Firstly, the installation priority of the pressure gauge in water distribution networks can be determined with a more objective standard through the entropy theory. Secondly, the model can be used as an efficient decision-making guide for gauge installation in water distribution systems.     

自激振荡磨料射流的基本理论与初步试验

自激振荡磨料射流是在自激振荡脉冲射流和前混合磨料射流基础上,提出的新型射流。为此,重点讨论了自激振荡磨料射流喷嘴的结构和工作原理,分析了脉冲频率和幅值等参数对磨粒加速效果的影响。根据初步研究表明,磨粒速度受脉冲频率和幅度影响很大,磨粒速度可超过前混合磨料射流中磨粒的速度,最大钻孔速度比前混合磨料射流提高４１％ 。这一成果有望用于坚硬物料的切割和特种加工、石油钻井、大洋采矿、难采矿体的开采、坚硬岩石巷道（遂道）掘进、表面清洗等领域。     

应用事故致因理论，研究事故预防对策──关于防止铁路机车车辆伤害事故的探讨

应用事故致因理论，探讨机车车辆伤害事故的本质，研究机车车辆伤害事故的发生规律及成因模型，提出预防机车车辆伤害事故的对策。