北京市工业污染源大气污染物排放特征

北京市工业污染源大气污染物排放比较严重，其TSP，PM10，PM2．5，SO2，NOx和CO的排放量均占北京市固定污染源排放量的54％以上，煤烟型污染是工业污染的主要部分，占源污染物排放量比面源大，污染物排放主要集中在电力行业和冶金行业，污染源主要分布在城八区中的外四区，特别是工业比较集中的石景山地区和朝阳区，工业污染源排放的颗粒物中细颗粒物比例较高。     

某综合楼墙体开裂原因及加固处理

对某综合楼墙体开裂原因进行了分析。并根据分析，判定结果提出了合理的加固处理方案。保证了房屋的安全使用，实践证明此方案是可靠和可行的。     

典型岩溶断陷盆地耕地承载状况时空分布特征

西南岩溶地区生态系统脆弱,人地矛盾尤其突出。为研究云南小江流域耕地生态承载状况,以2008、2011、2014、2017年统计数据为基础,应用生态足迹法和GIS技术在修正耕地产量因子的基础上从地貌分区对小江流域耕地4个节点的生态承载状况进行时空动态分析。研究结果表明:小江流域耕地生态足迹增长迅速,其中沉积平坝区、峰丛洼地区和台地槽谷区增长较快;耕地生态承载力先减后增,整体变化幅度较小;流域内除了岩溶河谷区北端耕地生态盈余以外,其余地区皆为生态赤字,对耕地的过度消耗利用,导致耕地处于高负荷状态,很不利于耕地的可持续利用,自2014年开始赤字状况有所好转。整体来看,岩溶中山区和河谷区赤字状况要优于沉积平坝区、峰丛洼地区和台地槽谷区。     

Transboundary Pollution between Guangdong Province and Hong Kong: Threats to Water Quality in the Pearl River Estuary and Their Implications for Environmental Policy and Planning

The Pearl River (Zhujiang) is the largest river system in southern China. The river, which is approximately 2200 km long, discharges into the South China Sea through an extensive deltaic area to the west of Hong Kong. Water quality in the river is under threat from a variety of sources associated with industrializationand urbanization in the Pearl River Delta Region (PRDR). Hong Kong's location on the eastern bank of the Pearl River estuary means that the quality of its western marine waters is likely to be increasingly influenced by the Pearl's pollution burden. Little published material exists on pollution in the Pearl River, or the potential impacts of transboundary pollution on marine water quality in Hong Kong. This paper focuses on this issue of transboundary water pollution between the Delta Region and Hong Kong. Specifically, we present the results of a preliminary analysis of water quality data for the Pearl River. The paper demonstrates that the major potential problem affecting the Pearl River is organic pollution, and that the principal sources of pollution affecting the Pearl River estuary, and consequently Hong Kong's western waters, are the Shenzhen River, the upstream Guangzhou section of the Pearl River, and the Dongguan Canal. We estimate that less than 5% of untreated domestic sewage discharges affecting the estuary derive from Hong Kong itself. The paper also discusses the implications of transboundary pollution in the context of environmentalpolicy making in Hong Kong and argues that more extensive and effective co-operation and collaboration between Hong Kong and mainland agencies should be developed to address these concerns.     

Origin and assessment of groundwater pollution and associated health risk: a case study in an industrial park,northwest China

Groundwater quality which relates closely to human health has become as important as its quantity due to the demand for safe water. In the present study, an entropy-weighted fuzzy water quality index (WQI) has been proposed for performing groundwater quality assessment in and around an industrial park, northwest China, where domestic water requirements are solely met by groundwater. The human health risk was assessed with the model recommended by the United States Environmental Protection Agency. In addition, the sources of major ions and main contaminants were also analyzed. The study shows that groundwater in the study area has been contaminated conjunctively by natural processes and industrial and agricultural activities. Nitrate, manganese (Mn), fluoride, total dissolved solids, total hardness and sulfate are major contaminants influencing groundwater quality. Nitrate and heavy metals such as Mn are mainly affected by human agricultural activities and industrial production, while other contaminants are mainly originated from mineral weathering and water–rock interactions. The results of water quality assessment suggest that half of the groundwater samples collected are of medium quality thus require pretreatment before human consumption. The mean health risk caused by the consumption of contaminated groundwater in the area is 8.42 × 10^?5 per year which surpasses the maximum acceptable level (5 × 10^?5 per year) recommended by the International Commission on Radiologic Protection. The entropy-weighted fuzzy WQI proposed in this study can not only assign proper weights to parameters but also treat uncertainties associated with water quality classification. This study will be of interest to international environmentalists and hydrogeologists. It will also be useful in regional groundwater management and protection.     

液化石油气容器受热下蒸气爆炸及影响因素的研究

液化石油气的生产、储运过程中,由火焰加热引发的蒸气爆炸事故屡有发生,并常相继导致其他类型的爆炸。分析了蒸气爆炸的危害特性,研究了影响蒸气爆炸的因素,对火灾的预防和扑救具有一定实用意义。     

Stability of workface using long-wall mining method in extremely thin and gently inclined iron mine

Long-wall mining method has its own advantages, such as small mining-cutting ratio, the simple technique of recovery and high level of mechanization, which is the optimal method used to mine gently inclined and extremely thin iron mine. How to ensure the safety of workers and equipment during mining is the key technical process. Based on elastic-plastic mechanics theory, the mechanic model of long-wall method mining gently inclined and extremely thin iron mine is established and the critical safety distance of workface is obtained. With the FLAC-2D simulation software, the rule of stress change, the deformation of workface and surrounding rock in different control-roof width are also summarized. The final results accord with the ones of theory test. We confirm the support-frame resistance of workface by analogy-statistic method. The results prove that hydraulic support-frame have the ability to provide enough pressure to assure the stability of working face within the 5-m of control-roof width.     

Numerical simulation on foam ceramic blasting block device under the action of explosion transform

The responsive behaviour of the action of under explosion blasting block damaging device structure was investigated based on quality equation, energy conservation equation and thermodynamics equation, using the ANSYS finite element simulation and Euler form of momentum equation. This paper analyzed the destructive situation of the inside and outside of the foam ceramic device. The research shows that the finite element simulation results and the numerical calculation results agree, which provides important reference basis in the anti-explosion design and improvement of cut off the device for blasting.     

码头油品蒸气云爆炸事故危害评价

运用“蒸气云爆炸”模型,对某码头油品蒸气云爆炸事故危害程度进行分析评价,得出油品爆炸事故危害程度分布的规律,为码头安全运行提供参考。     

气体压缩输送设备的防火与防爆

本文综合分析了气体压缩输送设备火灾爆炸事故的原因和机理,提出了气体压缩输送设备的防火防爆技术措施.