北京市控制PM2.5污染的健康效益评估

实施PM_2.5污染控制后所带来的居民健康经济效益评估,对推进区域环境空气质量监管、健康预警以及防治等工作具有重要意义.本文采用泊松回归相对危险模型和环境价值评估方法,对2016~2019北京16个辖区年PM_2.5污染控制到二级标准限值35 μg·m^-3后所带来的健康风险及经济效益进行评估.结果显示,2016~2019年北京及其16个辖区PM_2.5浓度、各健康终端效应、经济效益以及人均经济健康效益等均呈现出下降趋势.其中,北京PM_2.5浓度值从2016年的73 μg·m^-3下降至2019年的42 μg·m^-3,年均下降率为16.75%,控制PM_2.5污染的健康总受益人数从2016年的439985例（95%置信区间：183987,653476）下降到2019年的77288例（95%置信区间：30483,120905）,年平均下降率约为42.67%.健康经济效益占GDP的比重从3.16%（95%置信区间：1.10%,4.73%）下降到0.55%（95%置信区间：0.18%,0.88%）,人均健康经济效益从3727.61元（95%置信区间：1303.24,5592.18）下降到906.58元（95%置信区间：295.14,1438.27）.此外,由于PM_2.5浓度、人口数量和密度以及单位健康终端经济价值的差异使得北京16个辖区的健康经济效益、占GDP比重以及人均效益估算结果各有差异,其中丰台、通州和大兴等远高于其他辖区,健康风险与经济效益问题相对突出.     

系统电磁环境效应要求和试验评估研究

目的提高武器系统适应日益复杂的电磁环境,提升装备的作战效能,提出合理的系统电磁环境效应要求,并开展试验评估,以验证指标是否得到满足。方法采用基于使用需求和标准分析的方法,针对系统级电磁环境效应的复杂性和特殊性,通过对电磁环境效应要求和标准的分析,提出采用建模仿真,预测电磁环境,开展缩比模型、1︰1模型试验验证等方法确定电磁环境效应指标和要求。结果提出了系统内自兼容、系统间兼容性和系统与外部电磁环境3大类14小类的系统电磁环境效应要求,分析了每项电磁环境效应要求对四大类典型系统的适用性,提出了开展系统电磁环境效应试验的方法和流程,为开展装备系统级电磁环境效应工程研制、试验和评估提供了技术支撑。结论采用提出并确定系统电磁环境效应要求和试验评估方法,实施武器系统的电磁环境效应控制和评估,对装备使用性能的充分发挥具有十分重要的意义。     

两种生态净化措施对水源水库光学环境的影响

为了评估生态净化措施对水体光学环境的影响,以上海金泽水库为例,在微纳米曝气复氧和水生植物净化两种生态净化措施前后布设采样点进行了光学衰减系数（水体光合辐照度（PAR）衰减系数）、真光层深度和透明度及相关水质指标的监测和分析.结果表明：水生植物净化和曝气复氧净化措施有利于水体光学环境的改善,经微纳米曝气后,水体透明度增大20%~25%,真光层深度增大2.2%~14.8%,光学衰减系数降低0.4%~4.4%;经水生植物净化后,水体透明度增大20%~29.4%,真光层深度增大6%~20%,光学衰减系数降低17.3%~20.5%.逐步回归结果表明不同生态净化措施的光学环境改善机制不同,微纳米曝气主要通过叶绿素、溶解性有机物、温度、溶解氧影响水体光学环境,水生植物净化主要通过浊度影响水体光学环境.冬季,两种生态净化措施对总氮和溶解性有机物均没有改善效果.     

特种车辆雷电效应仿真分析

雷电是一种极具破坏性的自然现象,产生的电磁干扰会对电气设备造成影响,采取仿真分析的手段可提前发现车辆雷电防护设计的薄弱环节。针对某特种车辆热待机工况下,雷电击中附近避雷针时,对车辆所处的电磁环境特点进行了仿真分析,为特种车防雷设计和雷电验证试验提供支撑和参考。     

复式潜流湿地净化生活污水的试验研究

研究了新型复式潜流人工湿地对生活污水的净化效果。在不同水力负荷、季节、曝气方式等条件下经过小试试验,分析了该湿地对污染物净化效果的影响。结果表明,该系统出水水质稳定,达到《城镇污水处理厂污染物排放标准》（GB18918--2002）的一级A标准。在水力负荷184mm·d。条件下COD、NH,一N去除率最大分别可达87．2％、68．9％。冬季低温条件下对各类污染物去除率仍大于20％。正交试验分析得知,最佳运行条件是气温28．6℃、水力负荷0．184m3·m-2·d-1、水力停留时间2．4d。对比试验表明,采用预曝气方式对湿地净化效果明显优于厌氧处理。     

飞行器雷电间接效应危害及其防护研究

雷电对飞行器的损伤作用分为直接效应和间接效应,间接效应可能导致内部电子电气设备及系统功能紊乱或丧失。本文在分析雷电特性的基础上,应用理论分析和计算的方法,探究了飞行器雷电间接效应的作用机理,并结合GJB 1389A[1]、GJB 2639-1996[2]等标准对间接效应试验和雷电防护方案进行了设计。     

中国大河流域开发与国家文明发育

水是生命之源。大河流域既是地球淡水资源的关键载体,也是人类文明发育的主要摇篮。作为世界文明古国和现代发展中大国,中国的情况更是如此。长期的实践表明,大河流域的开发具有明显的生态效应极化特征:即在人文生态系统获取快速发育的同时,严重干扰和破坏了流域自然生态的系统发育及其多样化的发展。流域开发的程度越高,这种极化效应的特征也就越明显。论文的实证分析表明,由于缺乏流域开发生态效应的正确认识和过分追求人文发展利益发育最大化,黄河和长江两大流域的资源环境承载能力正在面临着日趋严峻的挑战。例如,河水断流、水质污染、湿地萎缩和水生物种消亡。为国家现代文明的永续发展计,亟需改变目前传统的"重开发、轻保护"大河流域资源环境开发观。     

Transformations in carbon and nitrogen-forms in peat subjected to progressive thermal stress as revealed by analytical pyrolysis

To study the characteristic N-forms of humic-type materials, samples of sapric peat from Galicia (northern Spain) were heated at 350 °C for 60, 90, 120, 150 and 180 s, and studied by Curie-point Py-GC/MS, solid-state CPMAS ¹³C-NMR and ¹⁵N-NMR spectroscopies. NMR analysis of the peat samples in the progressive heating stages showed the concentration of heterocyclic N-forms, the maximum structural transition amide-to-heterocyclic forms being observed in samples heated for 120 s (56% heterocyclic N and 34% aromatic C). Under more drastic conditions all N-forms were depleted. Correlation between spectroscopic and pyrolytic data betrayed specific pyrolytic markers for the different N-forms. The intensity of the ¹⁵N-NMR amide peak tended to be positively correlated to the yield of indoles, imidazoles and pyrazoles, and negatively correlated to those of benzonitriles and pyrazines. Analytical pyrolysis also showed a progressive enrichment in lipids and alkyl macromolecules with increasing heating intensity, and a decrease in lignin-derived, polysaccharide-derived and N-containing compounds. The relative abundance of non-methoxyphenolic aromatic compounds did not change. The N-compounds in peat samples unheated or heated for 60–90 s released methylpyrazole, dimethylpyrroline, methyldiphenylindole and pyrazole, whereas peat samples heated for 120 s mainly yielded methylpyrazine and methyldiphenylindole. Dimethylpyrroline and pyrazine prevailed in samples heated for 150 s, whereas samples heated for 180 s yielded mainly pyrrole. Pyrolysis data presented low possibilities for forecasting the extent of the O-alkyl domain, but reflected quantitatively the transformations in the lignin-like moiety. Both techniques coincide in pointing out the accumulation of a recalcitrant alkyl domain possibly derived from abiotic condensations or inherited lipid biomacromolecules.     

Incorporating Climate Science in Applications of the U.S. Endangered Species Act for Aquatic Species

Aquatic species are threatened by climate change but have received comparatively less attention than terrestrial species. We gleaned key strategies for scientists and managers seeking to address climate change in aquatic conservation planning from the literature and existing knowledge. We address 3 categories of conservation effort that rely on scientific analysis and have particular application under the U.S. Endangered Species Act (ESA): assessment of overall risk to a species; long‐term recovery planning; and evaluation of effects of specific actions or perturbations. Fewer data are available for aquatic species to support these analyses, and climate effects on aquatic systems are poorly characterized. Thus, we recommend scientists conducting analyses supporting ESA decisions develop a conceptual model that links climate, habitat, ecosystem, and species response to changing conditions and use this model to organize analyses and future research. We recommend that current climate conditions are not appropriate for projections used in ESA analyses and that long‐term projections of climate‐change effects provide temporal context as a species‐wide assessment provides spatial context. In these projections, climate change should not be discounted solely because the magnitude of projected change at a particular time is uncertain when directionality of climate change is clear. Identifying likely future habitat at the species scale will indicate key refuges and potential range shifts. However, the risks and benefits associated with errors in modeling future habitat are not equivalent. The ESA offers mechanisms for increasing the overall resilience and resistance of species to climate changes, including establishing recovery goals requiring increased genetic and phenotypic diversity, specifying critical habitat in areas not currently occupied but likely to become important, and using adaptive management. Incorporación de las Ciencias Climáticas en las Aplicaciones del Acta Estadunidense de Especies en Peligro para Especies Acuáticas     

氮氧化物(NOx)废气治理工程实例

针对氮氧化物(NOx)废气瞬时爆发性浓度极高、气量大,难于治理的危害特性,设计了一套适合敞开作业的通风净化系统装置。该工程既解决了原有NOx废气处理工艺的难题,提高NOx废气处理技术,又解决了"黄龙"对大气的污染,达到保护环境与社会和谐的统一。