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51.
新型天然海藻絮凝剂处理食品废水的研究 总被引:3,自引:0,他引:3
比较各种絮凝剂的优劣后,选用海藻直接制作天然高分子有机絮凝剂,采用正交表L8(34)设计试验方案.大量试验结果显示,用该絮凝剂处理COD初始质量浓度为3 000~13 000mg/L的蛋白废水,存在一个适宜的投加量和pH范围,投加质量浓度为12.5 g/L、pH2~4时,COD去除率大于70%,最高可达79.56%;室温下絮凝反应快,生成絮体大,自然沉降快.研究表明,该絮凝剂可有效去除COD,操作条件温和,且无毒、无害、无重金属残留,可处理食品行业的蛋白废水,絮凝产物可回收作饲料添加剂,具有良好的开发前景. 相似文献
52.
No school is an island; it is a part of a continuum or a pipeline of institutions which together form an educational pipeline through which groups of students pass. To turn a body of data into useful information for knowledge-based decision-making at any level, data must be collected, organised, analysed and reflected upon. The purpose of this paper is to discuss how schools and other educational institutions can not only collect better data but learn how to transform that data so that the information held within can be effectively shared among all stakeholders. This process will help to ensure that the school and the entire education system provide a more seamless and effective educational pipeline for students, and ultimately improve the quality of education delivered in the country as a whole. 相似文献
53.
Miklas Scholz Jing Xu Hilary I Dodson 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2001,76(8):827-835
The aim of this study was to investigate the treatment efficiency of passive vertical‐flow wetland filters containing Phragmites australis and/or Typha latifolia and granular media of different adsorption capacities. A cost–benefit analysis was performed on the characteristics of constructed wetlands. Cheap gravel and sand as well as expensive granular activated carbon, charcoal and Filtralite (light expanded clay) were used as filter media. Different concentrations of lead and copper sulfate were added to polluted urban beck inflow water in order to simulate pre‐treated mine wastewater, landfill leachate or highway runoff. The relationships between growth media, microbial and plant communities as well as the reduction of lead, copper, five‐day biochemical oxygen demand (BOD) in particular, and potentially pathogenic bacteria were investigated. A breakthrough of copper within the first 9 weeks was only recorded for filters containing media with limited adsorption capacities. The breakthrough was independent of the presence of plants. However, after maturation of the biomass, which dominated the schmutzdecke and litter zone, lead and copper concentrations were reduced by 97–99% and BOD by 41–60% in all wetlands. There appears to be no additional benefit in using macrophytes and expensive adsorption media in constructed wetlands to enhance metal reduction during the set‐up period of 5 months. © 2001 Society of Chemical Industry 相似文献
54.
Schwebel David C.; Swart Dehran; Simpson Jennifer; Hui Siu-kuen Azor; Hobe Phumla 《Canadian Metallurgical Quarterly》2009,28(4):493
Objective: Unintentional injury rates in low- and middle-income countries are up to 50 times higher than high-income nations. In South Africa, kerosene (paraffin) is a leading cause of poisoning and burns, particularly in low-income communities where it serves as a primary fuel for light, cooking, and heating. This study tested a community-based intervention to reduce kerosene-related injury risk. The intervention used a train-the-trainers model, whereby expert trainers train local paraprofessionals, who in turn deliver educational materials to community residents. The intervention was theory-driven, pragmatically motivated, and culturally sensitive. Design: Prospective quasi-experimental intervention design with nonequivalent case versus control groups. Main Outcome Measures: Three primary outcome measures were considered: self-reported knowledge of kerosene safety, observed practice of safe kerosene use, and self-reported recognition of risk for kerosene-related injury. Results: ANOVA models suggest a large and significant increase in self-reported kerosene-related knowledge in the intervention community compared to the control community. There were smaller, but statistically significant changes, in kerosene-related safety practices and recognition of kerosene injury risk in the intervention community compared to the control community. Conclusion: The intervention was successful. A train-the-trainers model might be an effective educational tool to reduce kerosene-related injury risk in low-income communities within low- and middle-income countries. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Processing is a programming language and environment built for the media arts communities. It is created to teach fundamentals of computer programming within the media arts context and to serve as a software sketchbook. It is used by students, artists, designers, architects, and researchers for learning, prototyping, and production. This essay discusses the ideas underlying the software and presents its relationship to open source software and the idea of software literacy. Additionally, Processing is discussed in relation to education and online communities. 相似文献
56.
Daniel Memmi 《AI & Society》2006,20(3):288-300
The impressive development of electronic communication techniques has given rise to virtual communities. The nature of these computer-mediated communities has been the subject of much recent debate. Are they ordinary social groups in electronic form, or are they fundamentally different from traditional communities? Understanding virtual communities seems a prerequisite for the design of better communication systems. To clarify this debate, we will resort to the classical sociological distinction between small traditional communities (based on personal relations) and modern social groups (bound by looser, more impersonal links). We will argue that the discussion about virtual communities is often vitiated by a simplistic assimilation to traditional communities, whereas they may be in fact quite different and much more impersonal. Virtual communities are often bound by reference to common objects or goals, and not by personal relations. In this respect, virtual communities are just another example of a long-term evolution of modern society toward more abstract social relationships. 相似文献
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59.
昆明房地产开发与城市可持续发展研究 总被引:1,自引:2,他引:1
随着城市化的到来,城市的可持续发展变得更为重要,房地产开发应贯彻可持续发展思想,将社会效益和环境效益放在第一位,通过多学科的融贯研究,建设可持续发展的绿色生态社区,为美化春城做贡献。 相似文献
60.