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301.
为了顺应沿江开发战略,沿江地区设立了多个化学工业园。随着因区企业的陆续建成投产,在不利气象条件下化工园排放的有机污染物异味扰民时有发生。严重影响化工园周边地区群众的生活。某化学工业园废气特异指标氯苯类、贲亭酸甲酯和异戊烯醇是异味的主要来源,其相应的监测分析方法氯苯类国内有标准方法,贲亭酸甲酯和异戊烯醇国内未见报道。为了掌握第一手监测数据资料,笔者对某化学工业因特异指标氯苯类、贲亭酸甲酯和异戊烯醇的监测分析方法进行了探索,获得了一种简便可行的定量监测分析方法。此方法使用活性炭吸附,二硫化碳解析和GC—FID(气相色谱-氢火焰光度法)分析一并完成3个化舍物的分析,简单快捷、成本低廉,可供参考。 相似文献
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硫化氢的净化技术及研究进展 总被引:1,自引:0,他引:1
综合评述了硫化氢废气的各类净化方法及最新的研究进展。硫化氢废气常规净化的方法有氧化法、吸收法、吸附法等,目前净化硫化氢废气的主要新技术,包括生物法、臭氧氧化法、电化学法和电子束照微波分解法。重点论述了生物法和电化学法净化工艺,生物法主要用于低浓度大气量的硫化氢废气的处理,具有设备简单、运行费用低,较少形成二次污染等优点;电化学法具有处理效率高、操作简便、不产生副产物或二次污染物等优点。这两种方法发展前景非常广阔,是今后发展的一个方向。 相似文献
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Current standard test methods for electric-spark minimum ignition energies (MIEs) of dust clouds in air require that a series inductance of at least 1–2 mH be included in the electric-spark discharge circuit. The reason is to prolong the spark discharge duration and thus minimize the spark energy required for ignition. However, when assessing the minimum electrostatic energy ½CU2 for dust cloud ignition by accidental electrostatic-spark discharges, current testing standards require that the series inductance of at least 1–2 mH be removed from the spark discharge circuit. No other changes of apparatus and test procedure are required. The present paper questions whether this simple approach is always adequate. The reason is that in practice in industry accidental electrostatic-spark discharge circuits may contain large ohmic resistances due to corrosion, poor electrical grounding connections, poorly electrically conducting construction materials etc. The result is increased spark discharge durations and reduced mechanical disturbance of the dust cloud by the blast wave emitted by the spark. Therefore, testing for minimum ½CU2 for ignition by accidental electrostatic spark discharges may not only require removal of the series inductance of 1–2 mH from the standard MIE spark discharge circuit. Additional tests may be needed with one or more quite large series resistances Rs inserted into the spark discharge circuit. The present paper proposes a modified standard test procedure for measurement of the minimum electrostatic-spark ignition energy of dust clouds that accounts for these effects. 相似文献
307.
FloodProBE: technologies for improved safety of the built environment in relation to flood events 总被引:1,自引:0,他引:1
C.C.D.F. van Ree M.A. Van K. Heilemann M.W. Morris P. Royet C. ZevenbergenAuthor vitae 《Environmental Science & Policy》2011,14(7):874-883
The FloodProBE project started as a FP7 research project in November 2009.Floods, together with wind related storms, are considered the major natural hazard in the EU in terms of risk to people and assets. In order to adapt urban areas (in river and coastal zones) to prevent flooding or to be better prepared for floods, decision makers need to determine how to upgrade flood defences and increasing flood resilience of protected buildings and critical infrastructure (power supplies, communications, water, transport, etc.) and assess the expected risk reduction from these measures.The aim of the FloodProBE-project is to improve knowledge on flood resilience and flood protection performance for balancing investments in flood risk management in urban areas. To this end, technologies, methods and tools for assessment purposes and for the adaptation of new and existing buildings and critical infrastructure are developed, tested and disseminated.Three priority areas are addressed by FloodProBE. These are: (i) vulnerability of critical infrastructure and high-density value assets including direct and indirect damage, (ii) the assessment and reliability of urban flood defences including the use of geophysical methods and remote sensing techniques and (iii) concepts and technologies for upgrading weak links in flood defences as well as construction technologies for flood proofing buildings and infrastructure networks to increase the flood resilience of the urban system.The primary impact of FloodProBE in advancing knowledge in these areas is an increase in the cost-effectiveness (i.e. performance) of new and existing flood protection structures and flood resilience measures. 相似文献
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Abstract Since the 1990s, with the in-depth study and understanding of sustainable development, quantitative study of regional sustainable development (RSD) was increasingly hot in China. Based on quantitative study of RSD from Core Periodical in China National Knowledge Infrastructure (1992–2008), statistical analysis on the annual distribution, periodicals distribution and changes of the distribution were made. And from perspectives of social–economic, ecological, systematic and emerging methods, the course, problems and trends of the quantitative study methods on RSD were examined and analyzed to get a clear summary. By the review, the context on the quantitative study of RSD was to be clarified. The study also showed that, primarily, fields involving quantitative study are expanding; second, big progresses and constant development have been made on the systematic method gradually sophisticated, the flourishing ecological method and emerging new methods in the context of cross and integration which has made complex integrated systems a more satisfactory solution; third, the method system has been more multi-angled, and the clues of independent innovation have been observed despite the fact that the introduction of imported method is the main trend. Although many problems exist, multi-scale study, dynamic timeseries study and inter-regional comparative study will be further exploited and increasingly carried out with the progress of spatial information technology, which would boost the development and application of new methods in RSD study. 相似文献
310.
Continuity and accuracy of near real‐time streamflow gauge (streamgage) data are critical for flood forecasting, assessing imminent risk, and implementing flood mitigation activities. Without these data, decision makers and first responders are limited in their ability to effectively allocate resources, implement evacuations to save lives, and reduce property losses. The Streamflow Hydrology Estimate using Machine Learning (SHEM) is a new predictive model for providing accurate and timely proxy streamflow data for inoperative streamgages. SHEM relies on machine learning (“training”) to process and interpret large volumes (“big data”) of historic complex hydrologic information. Continually updated with real‐time streamflow data, the model constructs a virtual dataset index of correlations and groups (clusters) of relationship correlations between selected streamgages in a watershed and under differing flow conditions. Using these datasets, SHEM interpolates estimated discharge and time data for any indexed streamgage that stops transmitting data. These estimates are continuously tested, scored, and revised using multiple regression analysis processes and methodologies. The SHEM model was tested in Idaho and Washington in four diverse watersheds, and the model's estimates were then compared to the actual recorded data for the same time period. Results from all watersheds revealed a high correlation, validating both the degree of accuracy and reliability of the model. 相似文献