宝天高速公路沿线地表水环境现状评价的密切值法

以宝天高速公路为背景,讨论了公路建设对水体环境的主要影响,并利用改进的密切值法对公路沿线地表水进行水环境质量现状评价.通过评价表明:沿线地表水质量良好,基本达到地表水环境Ⅰ级标准;评价结果真实地反映了天宝高速公路沿线水体水质的基本情况,说明采用密切值法对水体进行评价是可行的;该方法概念清晰、计算简便实用,能较好地反映区域内各水体水环境质量的相对优劣,可为制定环境规划、进行环境决策、实施环境综合整治提供科学依据.     

Role of cosubstrate and bioaccessibility played in the enhanced anaerobic biodegradation of organochlorine pesticides (OCPs) in a paddy soil by nitrate and methyl-β-cyclodextrin amendments

The present study was conducted to investigate the anaerobic biodegradation potential of biostimulation by nitrate (KNO₃) and methyl-β-cyclodextrin (MCD) addition on an aged organochlorine pesticide (OCP)-contaminated paddy soil. After 180 days of incubation, total OCP biodegradation was highest in soil receiving the addition of nitrate and MCD simultaneously and then followed by nitrate addition, MCD addition, and control. The highest biodegradation of chlordanes, hexachlorocyclohexanes, endosulfans, and total OCPs was 74.3, 63.5, 51.2, and 65.1 %, respectively. Meanwhile, MCD addition significantly increased OCP bioaccessibility (p?<?0.05) evaluated by Tenax TA extraction and a three-compartment model method. Moreover, the addition of nitrate and MCD also obtained the highest values of soil microbial activities, including soil microbial biomass carbon and nitrogen, ATP production, denitrifying bacteria count, and nitrate reductase activity. Such similar trend between OCP biodegradation and soil-denitrifying activities suggests a close relationship between OCP biodegradation and N cycling and the indirect/direct involvement of soil microorganisms, especially denitrifying microorganisms in the anaerobic biodegradation of OCPs.     

钱塘江沉积物对染料亮蓝的吸附作用及影响因素

以钱塘江沉积物为研究对象,以亮蓝作为染料污染物的代表,研究感潮河口沉积物对染料的吸附作用及相关影响因素.结果表明:(1)沉积物吸附亮蓝是一个快速吸附过程,在很短的振荡时间内就有较高的吸附率,振荡10 min吸附率即达49％.当亮蓝等染料污染物因突发事故或偷排、漏排等进入钱塘江后,染料分子能在很短时间内吸附在沉积物上,随沉积物的运动在钱塘江中迁移.(2)亮蓝在沉积物上的吸附主要以表面吸附作用为主,等温吸附线可用Langmuir吸附模型拟合.经计算,亮蓝在钱塘江沉积物上的饱和吸附量约为2 780 mg/kg.(3)含沙量、盐度等因素对钱塘江沉积物吸附亮蓝有显著影响.沉积物用量越大,亮蓝吸附率越高,但当20 mL亮蓝溶液中沉积物用量高于0.4g(即含沙量20 kg/m3)时,其吸附率基本保持不变；在低盐度范围内,等温吸附线区分度不大,当盐度上升到0.100 mol/L(以NaC1摩尔浓度表征盐度)时,吸附量出现显著增加.     

Effects of leachate accumulation on landfill stability in humid regions of China

Leachate levels are important to landfill stability and safety. High leachate or water levels often lead to landfill instability, which can cause accidents. Here a case study of a landfill located in a humid region of southern China is presented. Leachate distribution and quality were systematically analyzed, and the effect of leachate level on waste-mass stability was assessed. Boreholes were drilled in the field, samples were analyzed in the laboratory, and a simulation was performed. In addition, the safety and stability of the landfill was evaluated. The leachate level in the landfill was 9–19 m, which was higher than the top of the dam crest (8–20 m). Leachate accounted for more than 1/4 of the total landfill storage capacity. The contaminant concentration of the leachate samples collected directly from the waste body was very high, with large variation among the samples. The mean concentrations of NH₃–N, BOD, and COD from the waste body were 5404, 14,136, and 22,691 mg/L, nearly 2.7, 2.4, and 1.8 times the mean concentrations in the leachate pond, respectively. Three series of shear strength parameters were used in a slope stability analysis, and a limit equilibrium method was used to calculate the factor of safety (Fs). The analysis showed that Fs could be affected by potential anisotropy in the shear strength of the waste. The minimum values of Fs corresponding to series I were 1.84 and 1.17 for units ? and II, respectively. The Fs value of unit II was significantly lower than the safe design value (1.25). In addition, Fs decreased with increase in the normalized height of the leachate level, h/H, where h is the height of the leachate mound and H is the maximum thickness of the landfill. If the h/H values of units I and II are kept below 50% and 40%, respectively, a safe design value of 1.25 for Fs can be guaranteed. Therefore, some measures to prevent risk should be considered.     

中型景观尺度下斑块类型和地理特征影响杨树人工林干部病害的发生——以河南省清丰县为例

景观病理学在开展病原扩散、病害发生及其严重程度方面以其全新的视角,为森林病害的区域控制提供了新的研究技术及理论支持。首次利用景观病理学原理和方法对河南省清丰县一个中型景观下杨树人工林干部病害发生特征开展了研究,目的是解析在大尺度下斑块类型和地理特征对杨树人工林病害发生的影响。在100 km2的调查区域,以种植方式和林分类型划分斑块类型,分析显示发病株率在不同斑块间差异显著：农田间作斑块的林木发病株率显著低于孤立斑块、纯林斑块、混交林等斑块的发病株率;但发病株率在孤立斑块、纯林斑块及混交林等斑块间无显著差异。抚育管理措施对预防和减轻杨树人工林干部病害的发生起到关键左右：精细管理林分（有修枝、施肥和锄草）的林木发病株率（p=0.001）和发病指数（p〈0.001）均显著低于粗放管理林分（无修枝、无施肥和锄草等）。人类活动,如无序修剪和放牧很可能是造成村落附近林分发病率显著高于其他地点林分的主要原因。采用logistic回归,以品种编号、树龄、树高、林分密度、林分郁闭度、林分类型、斑块类型、地理特征,等为自变量建立病害发生预测模型。方程拟合达到极显著水平（Wald=71.248,p〈0.001）。方程总的预测正确率为68.2%,发病的预测正确率为79.8%。     

核电厂核事故应急疏散研究

根据我国法规、标准与美国核管委对核电厂核事故应急疏散的要求,考虑我国核电厂特殊的厂址条件与社会环境,分析核事故应急疏散的可行性。通过应急疏散行为研究、厂区的交通需求估计和路网分析,对不同情境,考虑核事故应急疏散的特殊问题,分别采用人工容量分析与宏观仿真模拟得到应急疏散时间。针对某核电厂,给出核事故应急疏散分析的一般步骤、方法与计算结果。对宏观仿真模型的主要参数进行灵敏度分析,找出影响应急疏散时间的主要因素,提出缩短应急疏散时间的针对性措施。     

Optimization of hydrogen distribution systems with pressure constraints

Hydrogenation units are often operated at high pressure, requiring the use of compressors which are one of the most expensive chemical processing equipment. Optimizing a hydrogen network should therefore take into consideration not only purity and flowrate constraints but also pressure requirements. In this paper, based on the hydrogen surplus diagram approach, the average pressure profiles of hydrogen sources and sinks are proposed through the introduction of a system’s minimum pressure drop Δp. Combined with the traditional purity profiles, whether a source can meet a sink either for hydrogen concentration or for pressure requirements can be determined intuitively. In cases where the pressure of a source is not sufficient for a sink, installing a hydrogen compressor or using another source with higher purity and pressure could be potential solutions. A cost equation is established to determine which of the two solutions is economically more viable. For different matching situations between sources and sinks, strategies for optimum placement of compression equipment within a given hydrogen network are proposed. A case study is used to illustrate the application and effectiveness of the proposed method.     

试用模糊数学方法对电焊作业防护措施进行综合评价

选择北京市四家锅炉厂的电焊工５６名，即从事手把焊、氩弧焊、ＣＯ２气体保护焊、电弧气爆等特种工种作业人员。通过调查，提出单项四级评分标准，再依模糊数学模型，进行综合评价。按Ｂ＝Ａ·Ｒ，求得Ｂ中最大元为０．７０７。最后总评为甲级。此结果与权数分配有关。此方法，可为劳动卫生管理（防护措施评级）提供依据。     

钻井废水的处理

本文针对钻井废水的处理，综述了现有的处理方法、处理药剂以及处理装置，并对钻井废水的处理、排放提出了一些意见和建议。     

燃烧风洞的研制及其燃烧特性研究

本文介绍了为可燃物燃烧特性研究而建立起来的模拟自然环境条件的燃烧风洞设备以及在燃烧设备中进行的模拟火场的火蔓延特性研究。在燃烧风洞中进行的可燃物燃烧实验为林火机理的研究、火蔓延模型的建立提供了实验依据．