静电放电电磁辐射模式的建立与仿真

介绍了静电放电电磁辐射场的理论模型;针对长导体模型分析了其数学模型的建立方法;讨论了长导体模型实验仿真方法与结果.     

体育教学反馈与自我反馈运用的探讨

体育教学过程中,教学效果的好坏取决于师生双方对过程的调控程度,而对技能教学的调控,则依据教师的教学反馈和学生的自我反馈来实现。在体育教学过程中,教学反馈与自我反馈的有机结合,是提高教学质量的关键。     

长期施肥对河西灌漠土有机氮组分的影响

在长期小麦和玉米轮作的基础上,通过单施化肥以及化肥与其它有机肥料的配合使用,研究不同施肥对河西灌漠土有机氮组分的影响.采用1965年Bremner提出的土壤有机氮分级方法,对22年有机肥与化肥定位试验中的耕层土壤有机氮组成进行分级.结果表明,长期施用化肥和有机肥对河西灌漠土全氮和土壤有机氮组成有显著影响,施肥对不同形态有机氮的影响取决于肥料种类.与单施化肥相比,有机肥与化肥配合施用后显著提高了土壤全氮、酸解性氮与非酸解性氮的含量.在酸解性氮中,氨基酸态氮和酸解未知氮显著增加,氨基糖态氮含量也有所提高.与不施肥相比,施用氮肥显著提高了土壤全氮、酸解性氮与非酸解性氮的含量.在酸解性氮中,化学氮肥显著提高了铵态氮的含量,对氨基酸氮、氨基糖氮和酸解未知态氮影响较小.施用磷、钾肥对河西灌漠土全氮和有机氮各组分含量影响较小.     

大孔吸附树脂对烷基酚聚氧乙烯醚的吸附行为

烷基酚聚氧乙烯醚(APEOn)是一类重要的非离子表面活性剂,由于其生物代谢产物被证实具有较大的毒性,因此引起人们广泛关注.本文使用两种不同的大孔吸附树脂XAD-4、NDA-804对APEOn类物质NP10进行吸附,该技术可为使用大孔吸附树脂去除此类污染物提供理论依据.研究结果表明:XAD-4、NDA-804对NP10都有较好的吸附效果,温度对吸附有较大的影响,升高温度吸附量增大.NDA-804对NP10的吸附效果要好于XAD-4,这与它的化学特性以及孔结构有关.NP1O在两种树脂上的吸附都能用Langmuir吸附等温线方程很好的拟合,表明属于单层分子吸附.吸附热力学参数计算结果表明,XAD-4、NDA-804对NP10的吸附过程是吸热和自发的.吸附动力学拟合结果表明,NP10在XAD-4、NDA-804上的吸附都符合假二级反应动力学.     

Capacity of transportation and spread of COVID-19—an ironical fact for developed countries

Environmental Science and Pollution Research - The widespread epidemic of the COVID-19 in developed countries such as Europe and the USA has sparked many speculations. What factors caused the rapid...     

Coupling urban 3-D information and circuit theory to advance the development of urban ecological networks

Ongoing, rapid urban growth accompanied by habitat fragmentation and loss challenges biodiversity conservation and leads to decreases in ecosystem services. Application of the concept of ecological networks in the preservation and restoration of connections among isolated patches of natural areas is a powerful conservation strategy. However, previous approaches often failed to objectively consider the impacts of complex 3-D city environments on ecological niches. We used airborne lidar-derived information on the 3-D structure of the built environment and vegetation and detailed land use and cover data to characterize habitat quality, niche diversity, and human disturbance and to predict habitat connectivity among 38 identified habitat core areas (HCAs) in Nanjing, China. We used circuit theory and Linkage Mapper to create a landscape resistance layer, simulate habitat connectivity, and identify and prioritize important corridors. We mapped 64 links by using current flow centrality to evaluate each HCA's contribution and the links that facilitate intact connectivity. Values were highest for HCA links located in the west, south, and northeast of the study area, where natural forests with complex 3-D structures predominate. Two smaller HCA areas had high centrality scores relative to their extents, which means they could act as important stepping stones in connectivity planning. The mapped pinch-point regions had narrow and fragile links among the HCAs, suggesting they require special protection. The barriers with the highest impact scores were mainly located at the HCA connections to Purple Mountain and, based on these high scores, are more likely to indicate important locations that can be restored to improve potential connections. Our novel framework allowed us to sufficiently convey spatially explicit information to identify targets for habitat restoration and potential pathways for species movement and dispersal. Such information is critical for assessing existing or potential habitats and corridors and developing strategic plans to balance habitat conservation and other land uses based on scientifically informed connectivity planning and implementation.     

Influence of surface properties of RO membrane on membrane fouling for treating textile secondary effluent

Environmental Science and Pollution Research - Reverse osmosis (RO) is a promising technology for treating and reusing textile secondary effluent (SE). To better understand the effect of membrane...     

Designing individualisation of eco information: a conceptual framework and design toolkit

Eco-labelling is the practice of eco information provision that most directly addresses consumer behaviour. Nowadays, consumers are facing difficulties in perceiving and understanding existing eco labels. In previous work, we proposed the conceptual framework of eco information individualisation which tailors eco labels according to the specific needs of individual users using contextual technologies. This paper extends the conceptual framework by introducing a more structured way of considering the personal data and product data requirements, and reports the development of a design toolkit that aims to support designers in the designing of individualised eco information. A design workshop was carried out to introduce the concept to designers, and evaluate the usability and usefulness of the toolkit. Positive responses were received. The design outputs generated from the workshop were considered largely feasible and have the potential to be developed into digital prototypes. These indicate that it is possible for designers to learn to design eco information individualisation in a short time. This paper is a step towards a greater understanding of designing individualised eco information.     

水资源规划优化技术研究进展及展望

文章针对水资源管理与规划的发展过程,详细论述了水资源系统管理与规划中常用优化技术的国内外研究成果及应用。根据是否考虑了模型参数或者模型结构的不确定性问题,将优化模型分为确定性优化模型和不确定性优化模型,同时对每种优化技术做了简要介绍,通过对不确定性优化模型的详细介绍指出了不确定性优化是当前水资源系统优化的热点;同时指出当前不确定性优化技术存在的问题,未来不确定性优化技术发展方向为多种不确定性以及多重效益的综合考虑等。