机器人技术在地震废墟搜索救援中的应用

破坏性地震往往会造成大量人员被掩埋在建筑废墟内,因此,被困人员的搜索救援是地震现场应急工作的重要任务。地震现场的搜索效率直接关系到地震救援工作的成功率,是提高被困人员生命存活率的重要因素。但是,强震发生后,地震现场往往余震频发、废墟内环境危险而又复杂,这些都给救援人员带来了极大的困难,也威胁着救援人员的生命安全。结合当前快速发展的搜救机器人技术研究现状以及地震应急救援中遇到的实际问题,提出了地震救援装备机器人化的研究设想,目的是提出地震救援人员对辅助搜索救援机器人的实际需求。同时介绍了中国地震应急搜救中心与国内多家院所合作完成的地震现场搜索救援机器人系列的研究现状,并分析了其优势与不足。所做的工作可为提高现场搜索救援效率,以及地震救援机器人的进一步研发与产业化参考。     

盐度对序批式反应器与间歇曝气膜生物反应器污水处理效果的影响

采用序批式反应器(SBR)与间歇曝气膜生物反应器(IAMBR)处理模拟生活污水,考察了进水盐度对两反应器污水处理效果的影响。研究表明,当进水盐度为0g/L(以NaCl质量浓度计,下同)时,SBR和IAMBR对总有机碳(TOC)、NH4+-N及TN的去除能力相当,IAMBR未表现出明显的优势;当进水盐度为10g/L时,SBR和IAMBR对TOC、NH4+-N及TN的去除产生明显的差异。IAMBR因为膜的截留与微生物富集作用,对污染物的去除无明显变化,依然保持了较高的污染物去除率,而SBR受盐度冲击影响较大,TOC、NH4+-N及TN的去除率均大幅降低,说明IAMBR具有较高的抗盐度冲击性能。     

Effects of reed straw, zeolite, and superphosphate amendments on ammonia and greenhouse gas emissions from stored duck manure

Stored poultry manure can be a significant source of ammonia (NH) and greenhouse gases (GHGs), including nitrous oxide (NO), methane (CH), and carbon dioxide (CO) emissions. Amendments can be used to modify physiochemical properties of manure, thus having the potential to reduce gas emissions. Here, we lab-tested the single and combined effects of addition of reed straw, zeolite, and superphosphate on gas emissions from stored duck manure. We showed that, over a period of 46 d, cumulative NH emissions were reduced by 61 to 70% with superphosphate additions, whereas cumulative NO emissions were increased by up to 23% compared with the control treatment. Reed straw addition reduced cumulative NH, NO, and CH emissions relative to the control by 12, 27, and 47%, respectively, and zeolite addition reduced cumulative NH and NO emissions by 36 and 20%, respectively. Total GHG emissions (as CO-equivalents) were reduced by up to 27% with the additions of reed straw and/or zeolite. Our results indicate that reed straw or zeolite can be recommended as amendments to reduce GHG emissions from duck manure; however, superphosphate is more effective in reducing NH emissions.     

西安市PM2.5污染特征及其估测模型

为了研究大气中PM25污染特征以及其随时间变化规律,基于西安市2013年1月-2014年4月间SO2、NO2、CO、03、日最高温度(Tmax)、日最低温度(Tmin)、PM2.5、PM10等因素的监测数据.运用统计学原理和多元回归分析方法,分析了PM25的污染特征及相关因素对其产生的贡献度,进一步建立了四季的最优多元回归模型.研究结果表明,西安市年平均质量浓度124.9 μg/m3,四季的平均污染浓度从大到小依次为冬、春、秋、夏;春夏两季贡献较大的为SO2、CO;秋冬两季贡献较大的为NO2、CO;最终建立的模型的相关系数较高,模型很好地拟合了冬春两季PM2.5变化趋势,能较准确地反映了西安市PM2.5的污染特征,具有一定的理论和实用价值.     

Ionic composition of wet precipitation over the southern slope of central Himalayas,Nepal

Severe atmospheric pollution transported to Himalayas from South Asia may affect fragile ecosystem and can be harmful for human health in the region. In order to understand the atmospheric chemistry in the southern slope of central Himalayas, where the data is limited, precipitation has been sampled at four sites: Kathmandu (1,314 m), Dhunche (2,065 m), Dimsa (3,078 m), and Gosainkunda (4,417 m) in Nepal for over a 1-year period characterized by an urban, rural, and remote sites, respectively. HCO₃ ^? is the dominant anion, while the NH₄ ⁺ is the dominant cation in precipitation at the four sites. Generally, most of ions (e.g., SO₄ ^2?, NO₃ ^?, NH₄ ⁺, HCO₃ ^?, and Ca²⁺) have higher concentrations in urban site compared to the rural sites. Neutralization factor calculation showed that precipitation in the region is highly neutralized by NH₄ ⁺ and Ca²⁺. Empirical orthogonal function and correlation analysis indicated that the precipitation chemistry was mostly influenced by crustal, anthropogenic, and marine sources in Nepal. Among different sites, urban area was mostly influenced by anthropogenic inputs and crustal dusts, whereas remote sites were mostly from marine and crustal sources. Seasonal variations show higher ionic concentrations during non-monsoon seasons mainly due to limited precipitation amount. On the other hand, lower ionic concentrations were observed during monsoon season when higher amount of precipitation washes out aerosols. Thus, precipitation chemistry from this work can provide a useful database to evaluate atmospheric environment and its impacts on ecosystem in the southern slope of central Himalayas, Nepal.     

Performance and Diagnostic Evaluation of Ozone Predictions by the Eta-Community Multiscale Air Quality Forecast System during the 2002 New England Air Quality Study

Abstract

A real-time air quality forecasting system (Eta-Community Multiscale Air Quality [CMAQ] model suite) has been developed by linking the National Centers for Environmental Estimation Eta model to the U.S. Environmental Protection Agency (EPA) CMAQ model. This work presents results from the application of the Eta-CMAQ modeling system for forecasting ozone (O₃) over the Northeastern United States during the 2002 New England Air Quality Study (NEAQS). Spatial and temporal performance of the Eta-CMAQ model for O₃ was evaluated by comparison with observations from the EPA Air Quality System (AQS) network. This study also examines the ability of the model to simulate the processes governing the distributions of tropospheric O₃ on the basis of the intensive datasets obtained at the four Atmospheric Investigation, Regional Modeling, Analysis, and Estimation (AIRMAP) and Harvard Forest (HF) surface sites. The episode analysis reveals that the model captured the buildup of O₃ concentrations over the northeastern domain from August 11 and reproduced the spatial distributions of observed O₃ very well for the daytime (8:00 p.m.) of both August 8 and 12 with most of normalized mean bias (NMB) within [H11006]20%. The model reproduced 53.3% of the observed hourly O₃ within a factor of 1.5 with NMB of 29.7% and normalized mean error of 46.9% at the 342 AQS sites.The comparison of modeled and observed lidar O₃ vertical profiles shows that whereas the model reproduced the observed vertical structure, it tended to overestimate at higher altitude. The model reproduced 64 –77% of observed NO₂ photolysis rate values within a factor of 1.5 at the AIRMAP sites. At the HF site, comparison of modeled and observed O₃/nitrogen oxide (NO_x) ratios suggests that the site is mainly under strongly NO_x-sensitive conditions (>53%). It was found that the modeled lower limits of the O₃ production efficiency values (inferred from O₃-CO correlation) are close to the observations.     

地下水浅埋区某加油站特征污染物空间分布简

加油站渗漏污染地下水已经是一个世界性的问题。由于浅埋区加油站储罐与地下水密切接触,更加剧储罐的腐蚀。为揭示加油站渗漏的典型污染物石油烃（TPH）、苯系物（BTEX）、萘和甲基叔丁基醚（MTBE）在该水文地质条件下的迁移变化,在浅埋区某加油站开展了平、枯、丰水期的地下水监测工作。在水平分布上,TPH、BTEX、萘基本相似,均在加油岛附近形成高浓度区,而MTBE则更易随地下水流动而迁移,呈现出不同的污染晕。在垂直分布上,地下水的水位变动是污染物浓度分布的主要影响因素。     

Characteristics in oxidative degradation by ozone for saturated hydrocarbons in soil contaminated with diesel fuel

Although alkanes are relatively less reactive to chemical oxidation compared to alkenes, the chemical oxidation of alkanes has not been adequately explored in the context of environmental remediation efforts. Laboratory-scale column experiments were therefore conducted with soil artificially contaminated by diesel fuel as a surrogate for alkanes of environmental relevance. Particular attention was paid to saturated hydrocarbons refractory to volatilization. Reaction conditions involve 1485mgkg(-1) of the initial concentration of diesel range organics (DRO) and a constant ozone concentration of 119+/-6mgl(-1) at the flow rate of 50mlmin(-1). The observed removal of DRO reached 94% over 14h of continuous ozone injection. Ozone oxidation demonstrated effective removal of non-volatile DRO in the range of C(12)-C(24). Each alkane compound displayed comparable degradation kinetics, suggesting virtually no selectivity of ozone reactions with alkanes in soil. A pseudo-first order kinetic model closely simulated the removal kinetics, yielding a reaction rate constant of 0.213 (+/-0.021)h(-1) and a half-life of 3.3 (+/-0.3)h under the experimental conditions used in this study. An estimate of ozone demand was 32mg of O(3) (mgDRO)(-1).