神农架大九湖泥炭地碳储量估算及固碳能力研究

通过对神农架大九湖泥炭地进行野外调查和长期观测,采用经验公式和实验室分析方法,计算了神农架大九湖泥炭地土壤有机碳含量和有机碳储量,并对2016-2018年神农架大九湖泥炭地的固碳能力特征进行了分析.结果 表明:在0～100 cm深度范围内,神农架大九湖泥炭地土壤有机碳含量的变化范围为282.90～516.10 g/kg...     

生理疲劳和心理疲劳对车辆驾驶的影响对比

针对现有疲劳驾驶预警和干预技术研究鲜有对生理疲劳和心理疲劳进行区分考虑的问题,为对比这两类典型疲劳态对驾驶员车辆驾驶过程的事故倾向影响,分别从性别、年龄和驾龄的角度分3批次共招募90位驾驶员进行状态诱发和驾驶实验。结果表明:尽管生理疲劳和心理疲劳都会如传统研究所述导致各驾驶员的驾驶违规倾向增加和驾驶能力降低,但是二者对于各类别驾驶员的驾驶影响程度和规律存在差异甚至迥异。研究疲劳驾驶相关问题时有必要首先判断驾驶员是生理疲劳还是心理疲劳,这是一个被普遍忽视而又可能影响研究结论准确性和有效性的重要因素。     

南京市环境保护能力建设探讨与研究

环保能力建设对于环保工作的顺利开展具有重要的支撑作用.目前南京市环保能力建设取得了一定的进步,然而,在经济新常态、绿色发展、政府简政放权、环保监察监测垂直化管理等新形势下,对照国家环境监管标准化,信息化和现代化的建设要求,南京市环保能力相对不足.文章基于南京环保统计数据,采用SWOT分析法对南京市环保能力建设情况进行研究,从源头减缓、人才队伍建设、资金投入、管理机制改革、技术支持、公众参与等方面,提出了若干政策建议.     

闽江干流下游河段纳污能力的研究

建立闽江干流下游河段二维非稳态水质水量模型,根据2004年实测资料对模型中的水质参数进行率定;对各排污口进行概化,应用模型模拟出闽江干流下游河段浓度场,并得出排污口混合带长度与排污量的响应关系;根据概化排污口在限定混合带长度下的平均纳污能力扩展到有效纳污能力计算长度后得到整个水体的纳污能力。经计算,闽江干流下游河段对COD的纳污能力为58195t/a。     

HCO3-对部分亚硝化-厌氧氨氧化联合工艺脱氮效能的影响

利用已经启动并达到稳定运行的部分亚硝化-厌氧氨氧化联合工艺,研究了HCO-3对部分亚硝化-厌氧氨氧化联合工艺脱氮效能的影响.结果表明,当C/N比由2降低到0.17时,因HCO-3投加量的限制,亚硝化区和厌氧氨氧化区p H值大幅下降,从而导致各区域氮素转化效能受限.联合工艺的氮去除速率由1.3 kg·(m3·d)-1下降到0.40 kg·(m3·d)-1,下降幅度达到69.3%.在联合脱氮工艺运行过程中,降低HCO-3对亚硝化菌、厌氧氨氧化菌和硝化细菌活性的影响依次下降.当C/N比恢复到1时,联合工艺的脱氮效能很快恢复到1 kg·(m3·d)-1,说明短期内HCO-3限制对联合工艺氮素转化效能的影响能够快速恢复.通过拟合后发现,进水C/N比值与联合工艺脱氮效能存在明显的相关性.     

基于城市大气环境荷载指数的大气污染排放变率估算

基于地面气象观测资料计算大气自净能力指数ASI,和环境监测站的实测PM_2.5浓度数据,利用城市大气环境荷载指数研究分析了2个时段单位人口的污染物排放率的变化,以及2013年9月~2019年2月京津冀及周边主要城市气象条件和减排措施对空气污染物浓度变化的作用.结果显示：秋冬季节污染物的削减力度明显大于春夏季.2014年秋冬季有74.5%城市实现减排,区域平均减排12.6%,减排初见成效;2017年和2018年秋冬季,京津冀及周边地区持续大幅减排,其中京津冀区域相对基准年分别减排54.0%和47.7%.长治市在2014~2017年秋冬季排放率均高于基准年,直至2018年冬季始实现减排27.6%;石家庄市排放率变化幅度波动较大,2016年冬季相比2014年冬季增加68.2%,今后区域污染物防控需要重点关注以上2个城市.城市大气环境荷载指数能够客观定量反映出典型减排时段的排放率变化方向和幅度,是一种评估气象条件和排放控制措施二者对污染物浓度变化各自作用的简单有效方法.     

新型环保水基渗透探伤剂的配制及性能研究

渗透探伤是一种重要的无损探伤技术。研究渗透性液体物性参数影响渗透过程的机制对渗透剂新产品的研发具有重要指导意义。配制了一种水基探伤用渗透性液体,探究了其表面张力、黏度和所用表面活性剂的HLB值对其铺展能力、毛细爬升高度、平衡渗透面积和渗透速度的影响。结果表明,液体的表面张力主要影响其铺展能力、毛细爬升高度和平衡渗透面积。表面张力越大,铺展能力越差,毛细爬升高度越大,平衡渗透面积越大。液体的黏度主要影响其渗透速度,黏度越大,渗透速度越慢。液体所用表面活性剂的HLB值对渗透效果没有明显的影响。     

Quantitative characterization of Cu binding potential of dissolved organic matter （DOM） in sediment from Taihu Lake using multiple techniques

Dissolved organic matter （DOM） plays an important role in heavy metal speciation and distribution in the aquatic environment especially for eutrophic lakes which have higher DOM concentration. Taihu Lake is the third largest freshwater and a high eutrophic lake in the downstream of the Yangtze River, China. In the lake, frequent breakout of algae blooms greatly increased the concentration of different organic matters in the lake sediment. In this study, sediment samples were collected from various part of Taihu Lake to explore the spatial difference in the binding potential of DOM with Cu. The titration experiment was adopted to quantitatively characterize the interaction between Cu（II） and DOM extracted from Taihu Lake sediments using ion selective electrode （ISE） and fluorescence quenching technology. The ISE results showed that the exogenous DOM had higher binding ability than endogenous DOM, and DOM derived from aquatic macrophytes had a higher binding ability than that derived from algae. The fluorescence quenching results indicated that humic substances played a key role in the complexation between DOM and Cu（II） in the lake. However, because of the frequent breakout of algae blooms, protein-like matters are also main component like hnmic matters in Taihu Lake. Therefore, the metals bound by protein-like substances should be caused concern as protein-like substances in DOM were unstable and they will release bound metal when decomposed.     

Research progress of nitrous oxide reductase gene (nosZII) and its relationship with the environment北大核心CSCD

The greenhouse effect has become increasingly serious globally. Nitrous oxide (N2O) is both the major ozone depleting substance and a potent greenhouse gas having a global warming potential 298 times that of CO2, and the N2O concentration is still increasing at an annual rate of about 0.8 × 10-9. Nitrous oxide reductase (N2OR) can reduce N2O to N2, and until recently, the nosZ gene was the only gene known to be able to encode N2OR. Besides the well-known nosZI, a new lineage of the N2O-reductase (nosZ clade II), which is abundant and widespread in soils, has been identified. In this paper, the main characters of nosZII-containing microbial communities and the related working mechanisms are summarized. In addition to the main differences between nosZI and nosZII, the important environmental factors that regulate the composition, abundance, and expression of nosZII-containing communities are also discussed in this paper. Studies have shown that nosZII communities are distributed among a diverse range of bacterial and archaeal phyla, such as Epsilon-proteobacteria, Bacteroidetes, and Aquificae. Interestingly, most of the nosZII microbes lack a nitrite reductase encoding gene (nirS or nirK) and are therefore unable to denitrify, indicating the importance of these communities as N2O sinks. Soil properties such as texture, pH, C/ N ratio, temperature, and lake physical gradient could regulate nosZII microbe abundance and diversity, and the pH and C/ N ratio may be the most important influencing factors. Studies on the ecological function of nosZII microbes have advanced considerably with the development of molecular biology technology. However, further studies on the community structure of nosZII microbes, the influencing factors of nosZII microbe abundance and diversity, and characteristics of nosZII strains with strong N2O reducing ability are needed. We hope to provide a theoretical basis that can be used to facilitate N2O reduction and relieve the greenhouse gas problem. © 2018 Science Press. All rights reserved.     

地矿系统矽肺与可疑矽肺的肺功能评价

本文通过对地质矿产系统１１５ 例矽肺与可疑矽肺的肺功能检查与分析，对矽肺呼吸功能障碍的性质与程度进行了评价；提出了肺功能检查能为矽肺患者代偿机能及劳动力鉴定提供辅助依据的见解；同时阐明了吸烟对肺功能的影响及小气道功能检查对早期发现亚临床期病人的意义