Seasonal variations of dissolved inorganic nutrients transported to the Linjiang Bay of the Three Gorges Reservoir, China

Field surveys were carried out from January 2007 to December 2008 to investigate seasonal variations of dissolved inorganic nitrogen (DIN) and phosphorus (DIP) transported to the Linjiang Bay of the Three Gorges Reservoir, China. The results revealed that both DIN and DIP exhibited large seasonal variability. DIN (dominated by NH₄?CN) concentrations were drastically higher in the dry season than those in the rainy season, and the same seasonal patterns of DIP concentrations and DIN and DIP fluxes were observed but inverse to that of DIN concentrations. The interannual variation in DIN fluxes descended by 28.2% from 2007 to 2008, while DIP fluxes increased by 40.9%, which were closely constant with interannual changes in DIN and DIP concentrations, respectively. The study indicated that nutrient fluxes (DIN and DIP) were strongly correlated with both nutrient concentrations and river discharge, and the Linjiang Bay received approximately 3,416 × 10³ kg DIN and 324 × 10³ kg DIP every year. In addition, DIN mainly originated from point sources, but DIP originated from non-point sources. It is shown that to control point source pollution is the most effective step for water quality improvement and reducing nutrient loading inputs in the Linjiang Bay.     

水泥工业原料的开发利用

本文从综合利用资源的角度出发，介绍了利用部份低品位矿产生产水泥工业原料、水泥产品具有显著的经济效益和社会效益。     

土地资源、环境与经济发展的协调性评价

评价系统发展协调性的“协调判别法”是这样一种方法：先为系统的各子系统选择一些有代表性又可用一定指标度量的要素，按一定标准将要素分作满意与不满意两类，统计加总各类要素的数量，以之作为度量用的综合指标，并经归一化处理得各子系统的“状态数”；再将这些子系统与一定的“状态空间”对应，在此空间中利用“状态数”确定子系统所属系统的“状态点”及“完全协调线”；然后分别计算状态点与协调线的距离（偏离度）、状态点与原点的距离（优化度），借助它们便可评价各子系统发展的同步性及相应系统的协调性。以此方法对通州市由土地利用、自然环境和社会经济3个子系统组成的系统进行的协调性评价表明，“协调判别法”具有含义明确、简单、较客观、易操作、可比性强的特点，适用于评价复杂系统的协调发展问题。     

淹没旋转射流的理论分析及力学模型

综述了淹没条件下旋转射流的基本特点、有关理论以及根据边界层流动的力学分析方法得出的淹没自由旋转射流和井筒空间的旋转射流的力学近似分析模型及其解析解,从而为全面深入地研究旋转射流的流动机理,指导该机理在石油工程中的应用,提供了理论基础。     

基于安全性的特种设备维修策略研究

针对我国目前安全生产形势，对特种设备使用与维修应予以特别重视，分析了特种设备维修管理现状及存在的问题，阐述了特种设备维修中的关键问题并提出了解决这些关键问题维修策略；利用计算机辅助故障树分析，找同特种设备维修重点；以特种设备的安全运行为目标；提出了合理维修周期求解模型；设计并实现了特种设备维修管理信息系统，将故障树分析和维修周期求解融入其中，实现了特种设备维修决策的科学化和规范化。实践证明，该信息系统实现了提出的维修策略，对提高特种设备的安全性和经济性有较大的实用价值。     

常用农药助剂类产品对水生生物效应研究进展

农药助剂是在农药制剂加工和使用中加入的除农药有效成分以外的其他辅助物质的总称。农药助剂在提高农药制剂药效、改善药剂性能、稳定制剂质量和降低活性成分危害等方面都起着相当重要的作用。几乎所有化学合成的农药原药都需添加农药助剂成为具有实际使用价值的农药制剂。农药助剂本身虽不具备对靶标生物的杀灭作用,但并不意味着其对环境或人体不具有危害性,部分现今仍在流通使用的农药助剂可导致健康危害,如致癌、致畸、致突变、危害神经系统,具有内分泌干扰作用等。截止目前,由于农药施用带来的农药助剂的危害问题很少引起研究人员关注,我国在农药助剂管理方面还是空白,亟需引起管理部门的重视并制订相关的防控法规。农药助剂种类繁多,我国习惯上将其分为非表面活性剂和表面活性剂两大类。本文总结了包括常用溶剂,非离子型、阳离子型和阴离子型表面活性剂在内的常用助剂对藻类、大型溞和鱼类等水生生物的急慢性毒性效应,并综述了烷基酚聚氧乙烯醚类助剂及其降解产物对水生生物的内分泌干扰效应。鉴于农药助剂对生态环境和人类的健康风险,本文还提出了我国农药助剂环境安全管理策略建议。     

液化气装置平台的抗震加固

针对装置平台抗震能力的现状 ,研究了江苏油田真武液化气装置平台的抗震加固。即在原设备不拆除的情况下 ,提出了对框架梁、柱采用钢构套进行加固 ,并对框架柱采用钢构斜支撑加翼补强的加固设计方案和具体的加固措施。经加固后的装置平台 ,整体抗震性能得到提高 ,从而消除了隐患 ,增强了日常工作的可靠性。     

Enhanced antioxidant capacity and upregulated transporter genes contribute to the UV-B-induced increase in blinin in Conyza blinii

Environmental Science and Pollution Research - Conyza blinii (C. blinii) is a traditional Chinese medicinal plant mainly grown in Sichuan, China. C. blinii is suitable for studying the mechanism of...     

Identifying unknown antibiotics with persistent and bioaccumulative properties and ecological risk in river water in Beijing,China

Environmental Science and Pollution Research - The goal of this study was to identify antibiotics with potential risk in river water of the megacity Beijing, China. This was accomplished by using a...     

Reproductive toxicity and underlying mechanisms of di(2-ethylhexyl) phthalate in nematode Caenorhabditis elegans

DEHP (di(2-ethylhexyl) phthalate) is an endocrine disruptor commonly found in plastic products that has been associated with reproduction alterations, but the effect of DEHP on toxicity is still widely unknown. Using DEHP concentrations of 10, 1, and 0.1 mg/L, we showed that DEHP reduced the reproductive capacity of Caenorhabditis elegans after 72 hr. of exposure. DEHP exposure reduced the reproductive capacity in terms of decreased brood sizes, egg hatchability (0.1, 1 and 10 mg/L), and egg-laying rate (1 and 10 mg/L), and increased numbers of fertilized eggs in the uterus (1 and 10 mg/L). DEHP also caused damage to gonad development. DEHP decreased the total number of germline cells, and decreased the relative area of the gonad arm of all exposure groups, with worms in the 1 mg/L DEHP exposure group having the minimum gonad arm area. Additionally, DEHP caused a significant concentration‐dependent increase in the expression of unc-86. Autophagy and ROS contributed to the enhancement of DEHP toxicity in reducing reproductive capacity, and glutathione peroxidase and superoxide dismutase were activated as the antioxidant defense in this study. Hence, we found that DEHP has a dual effect on nematodes. Higher concentration (10 mg/L) DEHP can inhibit the expression of autophagy genes (atg-18, atg-7, bec-1, lgg-1 and unc-51), and lower concentrations (0.1 and 1 mg/L) can promote the expression of autophagy genes. Our data highlight the potential environmental risk of DEHP in inducing reproductive toxicity toward the gonad development and reproductive capacity of environmental organisms.