浅谈住宅小区楼前排水检查井的做法

住宅小区污水管道施工是小区建设的重要环节.因小区面积不等、户型多样、情况复杂,检查井砌筑不慎将导致污水渗漏,污染地下水.检查井新施工工艺在施工前的准备工作、注意事项、优缺点以及与规范做法的不同之处.     

北京地区未来地震中各种类型建筑可能造成的人员死亡率

地震房屋倒塌率CR和地震死亡率FR存在一定的关系,据此,本文研究计算得到了北京地区在未来地震中各类建筑可能造成的人员死亡率FR.     

Bioabsorbable soy protein plastic composites: Effect of polyphosphate fillers on water absorption and mechanical properties

The use of synthetic and natural bioabsorbable plastics has been severely limited due to their low stiffness and strength properties as well as their strong tendency to absorb moisture. This research focused on the development of bioabsorbable polyphosphate filler/soy protein plastic composites with enhanced stiffness, strength, and water resistance. Bioabsorbable polyphosphate fillers, biodegradable soy protein isolate, plasticizer, and adhesion promoter were homogenized and compression-molded. Physical, mechanical, and water absorption testing was performed on the molded specimens. Results showed improvements in stiffness, strength, and water resistance with increasing polyphosphate filler content up to 20% by weight. Application of a coupling agent produced further mechanical property enhancements and a dramatic improvement in water resistance, interpreted by an interfacial chemical bonding model. Examination of the fracture surfaces of the materials revealed that the addition of the polyphosphate fillers changed the failure mode from brittle to pseudo-ductile. These results suggest that these materials are suitable for many load-bearing applications in both humid and dry environments where current soy protein plastics are not usable.     

Enzymatic Degradation of Cellulose-Based Materials

The biodegradability of cellulose-based materials was compared in the standard Sturm test and by enzymatic hydrolysis. Trichoderma reesei culture filtrate, the purified enzymes endoglucanase I and II from T. reesei, and -glucosidase from Aspergillus niger were used in the experiments. The unpurified Trichoderma reesei culture filtrate was found to contain a mixture of enzymes suitable for cellulose degradation. However, when purified enzymes were used the right balance of the individual enzymes was necessary. The addition of -glucosidase enhanced the enzymatic hydrolysis of cellulose materials when both culture filtrate and purified enzymes were used. In the Sturm test the biodegradability of most of the cellulose materials exceeded 70% carbon dioxide generation, but, in contrast, the biodegradability of the highly substituted aminated cellulose and cellulose acetate was below 10%. The results concerning enzymatic hydrolysis and biodegradability were in good agreement for kraft paper, sausage casing, aminated cellulose, and cellulose acetate. However, diverging results were obtained with cotton fabric, probably as a result of its high crystallinity.     

ON THE MISMATCH BETWEEN DATA AND MODELS OF HYDROLOGIC AND WATER RESOURCE SYSTEMS1

ABSTRACT: Many difficulties exist in the matching of models with data. This paper identifies elements of this problem and discusses considerations involved in model evaluation. The well known multivariate linear regression model is used to illustrate the distinctions between accuracy and precision and between estimation and prediction (because the model is commonly misused.) No amount of additional data will improve the accuracy of a poor model. A high R², while indicative of a good matching between the observed data and model estimates, is a poor criterion for judging adequacy of the model to make good predictions of future events. Model evaluation also includes the problem of introducing secondary data and proxy variables into a model. Secondary data frequently enter, for example, the mass, energy and water budget equations because of difficulties in measuring the primary variables. Proxy variables arise because of a desire to collapse a vector of incomparable values, say, of water quality into a single number. Review of the above issues indicates that model evaluation is a multi-criterion problem, often imbedded in a larger framework where models are intended to meet multiple objectives. The mismatch of models and data has increasing legal and social consequences.     

The effects of flooding upon buildings in developing countries

The genera] effects of flooding on buildings and structural materials in developing countries are comprehensively reviewed. The aim of the paper is to stimulate further field based research as to how and what type of building improvements can be introduced, given the prevailing economic and cultural constraints of many communities, and to examine the appropriateness of floodproofing measures in developing countries where there are often few floodplain management or large scale flood prevention schemes. Proposals are suggested as to the method and type of information which is required for detailed studies prior to developing new and more effective building designs.     

Science, Research, Knowledge and Capacity Building

A small part of the scientific community is seeking hard to enhance the contribution of science, knowledge and capacity building to environmentally sustainable and socially fair human development around the world. Many researchers over the globe share the same commitment – anchored in concerns for the human condition. They believe that science and research can and have influenced sustainability. Therefore their main goals are to seek and build up knowledge, know-how and capacity that might help to feed, nurture, house, educate and employ the world's growing human population while conserving its basic life support systems and biodiversity. They undertake projects, that are essentially integrative, and they try to connect the natural, social and engineering sciences, environment and development of communities, multiple stakeholders, geographic and temporal scales. More generally, scientists engaged in sustainable development are bridging the worlds of knowledge and action. This pro-active, heavily ethics- and wisdom-based "science for sustainability" can be seen as the conclusion of all dialogues and discussions amongst scientists at the World Summit on Sustainable Development (WSSD) 2002 in Johannesburg. The "Plan of Implementation" after WSSD will be based on political will, practical steps and partnerships with time-bound actions. Several "means of implementation" are going to be proofed and initiated: finance, trade, transfer of environmentally sound technology, and, last but not least, science and capacity building.Some characteristics of working scientific sustainability initiatives are that they are regional, place-based and solution-oriented. They are focusing at intermediate scales where multiple stresses intersect, where complexity is manageable, where integration is possible, where innovation happens, and where significant transitions toward sustainability can start bottom-up. And they have a fundamental character, addressing the unity of the nature – society system, asking how that interactive system is evolving and how it can be consciously, if imperfectly, steered through the reflective mobilization and application of appropriate knowledge and know-how. The aims of such sustainability-building initiatives conducted by researchers are: first to make significant progress toward expanding and deepening the research agenda of science and knowledge-building for sustainability; secondly to strengthen the infrastructure and capacity for conducting and applying science, research and technology for sustainability – everywhere in the world where it is needed; and thirdly, to connect science, policy and decision-making more effectively in pursuit of a faster transition towards real sustainable development. The overall characteristic is, that sustainability initiatives are mainly open-ended networks and dialogues for the better future. A world society that tries to turn towards sustainable development has to work hard to refine their clumsy technologies, in "earthing" their responsibility to all creatures and resources, in establishing democratic systems in peace and by heeding human rights, in building up global solidarity through all mankind and in commit themselves to a better life for the next generations.     

DESIGN AND IMPLEMENTATION OF A COOPERATIVE WATER QUALITY MONITORING PROGRAM IN COLORADO'S BIG THOMPSON WATERSHED1

ABSTRACT: In 1996, the Big Thompson Watershed Forum (BTWF) was formed “to assess and protect the quality of water” in the Big Thompson Watershed in northern Colorado. However, until 1999, water quality monitoring in the watershed was performed by many state, local, and federal agencies with no coordination among programs and with few efforts toward efficiency, data comparability, or information exchange. To better meet the needs of its stakeholders, the BTWF since 1999 has been actively pursuing the design and implementation of a cooperative water quality monitoring program. The program design involved consensus building among the funding participants, primarily drinking water providers. The final design included 38 parameters to be sampled 15 times per year at 24 stream and canal locations plus two reservoirs. Although the collaborative consensus based approach has been successful for the BTWF, this approach has its drawbacks; most notable among these are the time and labor this approach requires. Also, the BTWF struggled with achieving equal representation of all interests, since those agencies that provided funding had the greatest voice in the final product. While a collaborative approach may not always be best for monitoring program design, it should be appropriate for many watershed organizations that face the common problem of severe financial constraints.     

有害物质安全存贮地点的选址模型研究

有害物质对人类自身及其所处的环境造成的危害日益受到人们的重视 ,因此有必要选择适宜的地点安全存贮这些物质。笔者从总成本和危害程度两方面考虑 ,建立了双目标规划模型 ,力求使选址费用最低、对周围居民的危害最小。最后的实例说明模型是合理的。     

建筑和装饰材料的室内污染对人体危害及预防措施

建筑和装饰材料中 ,释放的挥发性有机化合物是导致室内空气污染的重要原因之一。建筑和装饰材料导致的室内污染 ,对人体健康的影响已成为人们关心的热门话题。笔者就建筑和装饰材料导致室内污染 ,对人体的危害及其预防措施进行了探讨。旨在提醒人们对这个问题引起重视 ,尽量减少其对人体的危害 ,起到宣传和教育作用