免疫磁珠分离与实时定量PCR技术联合检测水中轮状病毒的研究

建立了一种免疫磁珠分离技术联合实时定量PCR快速定量检测水中轮状病毒的方法.通过制备能够分离水中轮状病毒的特异免疫磁珠,优化分离条件,建立了免疫磁珠分离前处理方法,并与逆转录、实时定量PCR结合,成功用于水中轮状病毒的检测.研究发现,在1 mL水样中加入10 μL轮状病毒免疫磁珠、0.25 μL Tween 20、孵育2 h可达到较好的分离效果;免疫磁珠可用于3%牛肉浸膏等常用病毒洗脱液中的轮状病毒的分离,表明该分离技术能与已有的病毒浓集方法良好地整合.免疫磁珠分离技术与实时定量PCR联合用于检测水中轮状病毒,全过程需时约5 h,检测限为1×10⁴　copies/mL(相当于3～4　PFU/mＬ),检测结果与细胞病变试验检测结果有良好的线性相关关系（R²=0.981 6）,表明其能较好地表征水样的病毒感染风险.对接种已知量的轮状病毒的污水处理厂二级出水、再生水、地表水、自来水等水样的实验表明,该法可用于各种水样中轮状病毒的检测.     

Soil enzymatic activities and microbial community structure with di erent application rates of Cd and Pb

This study focused on the changes of soil microbial diversity and potential inhibitory effects of heavy metals on soil enzymatic activities at different application rates of Cd andor Pb. The soil used for experiments was collected from Beijing and classified as endoaquepts. Pots containing 500 g of the soil with different Cd andor Pb application rates were incubated for a period of 0, 2, 9, 12 weeks in a glasshouse and the soil samples were analyzed for individual enzymes, including catalase, alkaline phosphatase and dehydrogenase, and the changes of microbial community structure. Results showed that heavy metals slightly inhibited the enzymatic activities in all the samples spiked with heavy metals. The extent of inhibition increased significantly with increasing level of heavy metals, and varied with the incubation periods. The soil bacterial community structure, as determined by polymerase chain reaction-denaturing gradient gel electrophoresis techniques, was different in the contaminated samples as compared to the control. The highest community change was observed in the samples amended with high level of Cd. Positive correlations were observed among the three enzymatic activities, but negative correlations were found between the amounts of the heavy metals and the enzymatic activities.     

价值链管理在企业集团财务控制中应用的可行性分析

企业集团是现代社会中重要的经济组织形式,而财务控制在整个企业集团的管理控制中起着举足轻重的作用,但是传统的企业集团财务控制从理论到实践操作当中都存在着许多不可忽视的问题和缺陷.价值链管理作为一种全新的管理理论,无论从目标到特征还是控制模式都符合现代企业集团对企业集团财务控制的要求,所以能够很好的应用于企业集团的财务控制中,在企业集团财务控制中应用的可行性也就不言而寓了.     

利用稳定同位素技术研究外源物质输入对太湖微食物链的贡献

应用碳氮稳定同位素方法研究了太湖不同营养状态湖区内外源物质对微生物食物链主要成分的贡献.结果表明,在有大量外来物质输入的河口区,细菌、浮游枝角类、溶解性有机物(DOM)和颗粒性有机物 (POM)的δ¹³Ｃ 和δ¹⁵Ｎ同位素值,溶解性无机碳(DIC)的δ¹³Ｃ同位素值明显低于其它采样点,这表明河口区受陆源营养物质的影响强烈.其中,DOM的δ¹³Ｃ平均值和陆源C₃植物的δ¹³Ｃ值-26‰相近,表现出流域外源的排入对湖泊碳库的影响.与从DIC到浮游藻类的分馏值22‰计算得到的浮游藻类δ¹³Ｃ值相比,POM主要为内源藻类贡献.浮游枝角类的δ¹³Ｃ的平均值低于POM (0.2‰)和细菌 (2.5‰),这可能是由于枝角类脂类的积聚或选择性的摄食δ¹³Ｃ较为贫化的微型藻类(<50 μm)造成的.根据双组分混合模型(two-member mixing model),在河口区陆源C对细菌生物量的贡献占到61.2%,随着向湖心的推进,内源藻类的贡献逐渐增加(58.5%～92.9%).     

城市PM2.5扩散网络模型的研究

以复杂网络理论为基础,运用最短增广链算法构建城市PM2.5扩散的容量网络模型。通过分析城市环境中水平距离、海拔、风力等因素的作用,对PM2.5区域性扩散的物理过程进行一次有益的探索。西安市近期空气监测数据的实证分析显示,预测值与监测值基本吻合。同时,模型输出揭示了西安市PM2.5的扩散途径。     

新型填料A/O生物滤池处理低碳氮比农村污水脱氮

针对低碳氮比导致低污染农村污水生物处理时出水总氮(total nitrogen, TN)质量浓度高不能满足排放标准的问题,以普通砾石A/O生物滤池为对照组(1号),采用芦竹和活性炭分别作为缺氧段和好氧段填料的A/O生物滤池(2号)处理人工模拟农村污水并研究其脱氮效果.结果表明,当进水化学需氧量(chemical oxygen demand, COD)、氨氮(ammonia nitrogen, NH⁺₄-N)和TN质量浓度分别为(79.47±14.21)、(34.49±2.08)和(34.73±3.87)mg·L^-1时,两套装置对COD、NH⁺₄-N和TN的去除率分别为(88.00±7.00)%和(89.00±10.00)%、(90.00±2.00)%和(97.00±7.00)%、(37±15)%和(68±7)%,表明添加新型填料芦竹和活性炭能显著增强A/O生物滤池对NH⁺₄-N和TN的去除.高通量测序结果显示, 1号装置中参与硝化过程...     

新时期完善全链条环评管理制度的建议

环境影响评价（以下简称“环评”）制度作为生态环境源头预防的重要手段，有力支撑生态文明建设、推进生态环境治理能力现代化。当前，我国已建立了包括生态环境分区管控，项目环评、规划环评，以及区域发展战略（政策）评估的环评体系和排污许可管理制度体系，但是全链条环评管理在制度联动、衔接融合和管理闭环等方面仍存在薄弱环节。为进一步健全生态环境源头预防制度体系，须加快构建功能定位明确、责任边界清晰、衔接关系顺畅的全链条环评体系；建立生态环境分区管控与环评管理、排污许可等制度之间“四联动、三融合、两闭环”的基本模式。建议进一步完善全链条管理制度顶层设计，推动重点领域科技攻关，深化政策创新试点，强化能力建设，为推进美丽中国建设提供支撑保障。     

An improved grey wolf optimizer algorithm for identification and location of gas emission

Identification of the leakage of hazardous gases plays an important role in the environment protection, human health and safety of industry production. However, lots of current optimization algorithms, such as particle swarm optimization (PSO) and Grey Wolf Optimizer (GWO), suffer from poor global optimization capability and estimation accuracy. In this work, a hybrid differential evolutionary and GWO (DE-GWO) algorithm is proposed. Tested by simulation cases and Prairie Grass emission experimental data, DE-GWO shows higher estimation accuracy than GWO. Compared with the other four optimization algorithms, DE-GWO exhibits finer robust stability under different population sizes, fewer iterations, as well as higher estimation accuracy with fewer search agents. Importantly, simulation results demonstrate that DE-GWO is more suitable to apply in the scene with a small number of sensors. Therefore, the proposed in this paper outperforms other optimization algorithms for the gas emission inverse problem. DE-GWO can provide reliable estimation towards gas emission identification and positioning, which shows huge potential as the data analysis module of real-time monitoring and early warning system.     

Based on material flow analysis: Value chain analysis of China iron resources

Iron is an important basic resource for national economic development in China. It is of great strategic importance for the sustainable development of China's economy to study the utilization and circulation status of iron resources. In this paper, using the material flow and value chain analysis method, we quantitatively analyzed the value flow of iron resources in China. According to the value chain and price theory of element M, a value stream diagram of iron resources corresponding to the substance flow chart was plotted. Based on the previous material flow analysis result of iron resources, the diagram quantitatively depicted the value of the circulating flow of iron resources in China in 2011. The results show that by recycling materials, the value of the circulating flow of iron resources can bring considerable economic benefits to both producers and consumers. In the production stage, the expenditures of the entire economic system was reduced by 91.77 billion RMB by circulating iron and the income increased by 95 billion RMB by recycling home scrap, which was generated in the crude steel production stage. In the use stage of iron and steel products, the recycling of old scrap enabled the entire economic system to recover 370.78 billion RMB. It should be noted that analysis within a single framework of physical and economic characteristics of iron resources in the economic system can further extend the research chain of substance flow and value flow at the macro level, enhancing the economic value of substances flow research. In addition, by tracking and depicting the value flow cycle of elements, the improvement potentials and the value situations can be determined to provide useful information for conducting processing and technological innovation for waste minimization.     

Socially optimal and fund-balanced advanced recycling fees and subsidies in a competitive forward and reverse supply chain

Advanced recycling fees (ARFs) and government subsidy fees are important for curtailing the consumption of new products and encouraging recycling and disposal of end-of-life (EOL) products. We introduce a model consisting of a leader (the Environmental Protection Agency, EPA) and two groups of followers (MIS firms and recyclers) consisting of manufacturers, importers and sellers, and recyclers which compete in both consuming and recycling markets. The EPA determines the ARFs paid by the MIS firms and the fees subsidizing recyclers to maximize the social welfare in closed-loop supply chains where the MIS firms and recyclers attempt to maximize their respective profit functions. To compare with current practice, we describe a conceptual fund balance model to determine the ARF and subsidy fee on the basis of the balance between total collected ARFs and expenditure of subsidies. Using numerical examples for the laptop computer market in Taiwan, we demonstrate that our results outperform the current practice.