Pollution extents of organic substances from a coal gangue dump of Jiulong Coal Mine,China

This paper addresses the distribution and occurrence of harmful organic substances in coal gangue dump from Jiulong Coal Mine and its influence on the environment. The samples were taken from the coal gangue dump and coal waste water stream and analyzed by organic geochemical methods. The results indicate that the coal gangues contain abundant harmful organic substances like polycyclic aromatic hydrocarbons. The TOC and sulfur contents of the samples are much higher than those of the background sample except Sample JL7. The contents of organic bulk parameters are relatively high. Ten carcinogenic PAHs were identified and these harmful organic substances have influenced the surrounding area. Along the waste water stream, organic substances pollute at least 1,800 m far from the coal gangue dump.     

大直径单桩水平循环弱化有限元分析

处于复杂海洋环境下的大直径单桩基础需要承受波流等长期水平循环荷载作用,建立能反映其循环弱化特性的有限元分析方法尤为重要。为此,采用非线性运动硬化准则和饱和软黏土循环弱化模型描述土体循环加载时的滞回特性和强度弱化,并建议了模型参数的选取方法。为验证该本构模型在分析桩土循环弱化时的有效性,先将大直径单桩循环加载有限元模拟结果与离心试验结果进行对比。并进一步研究了循环位移幅值、弱化参数对于大直径单桩基础桩顶反力弱化的影响。     

Enhanced catalytic oxidation of 2,4-dichlorophenol via singlet oxygen dominated peroxymonosulfate activation on CoOOH@Bi2O3 composite

• Bi₂O₃ cannot directly activate PMS. • Bi₂O₃ loading increased the specific surface area and conductivity of CoOOH. • Larger specific surface area provided more active sites for PMS activation. • Faster electron transfer rate promoted the generation of reactive oxygen species. • ¹O₂ was identified as dominant ROS in the CoOOH@Bi₂O₃/PMS system. Cobalt oxyhydroxide (CoOOH) has been turned out to be a high-efficiency catalyst for peroxymonosulfate (PMS) activation. In this study, CoOOH was loaded on bismuth oxide (Bi₂O₃) using a facile chemical precipitation process to improve its catalytic activity and stability. The result showed that the catalytic performance on the 2,4-dichlorophenol (2,4-DCP) degradation was significantly enhanced with only 11 wt% Bi₂O₃ loading. The degradation rate in the CoOOH@Bi₂O₃/PMS system (0.2011 min⁻¹) was nearly 6.0 times higher than that in the CoOOH/PMS system (0.0337 min⁻¹). Furthermore, CoOOH@Bi₂O₃ displayed better stability with less Co ions leaching (16.4% lower than CoOOH) in the PMS system. These phenomena were attributed to the Bi₂O₃ loading which significantly increased the conductivity and specific surface area of the CoOOH@Bi₂O₃ composite. Faster electron transfer facilitated the redox reaction of Co (III) / Co (II) and thus was more favorable for reactive oxygen species (ROS) generation. Meanwhile, larger specific surface area furnished more active sites for PMS activation. More importantly, there were both non-radical (¹O₂) and radicals (SO₄⁻•, O₂⁻•, and OH•) in the CoOOH@Bi₂O₃/PMS system and ¹O₂ was the dominant one. In general, this study provided a simple and practical strategy to enhance the catalytic activity and stability of cobalt oxyhydroxide in the PMS system.     

Spatial systems approach to sustainable development: A conceptual framework

Even though “sustainable development” seems to have emerged as the development paradigm of the 1990s, a great deal of vagueness still surrounds the meaning, definition, and theoretical underpinnings of the concept. There is also a general lack of emphasis on the spatial dimension of sustainable development when developing relevant conceptual or environmental accounting frameworks. In clarifying the concept, this article proposes a definition that explicitly incorporates the temporal as well as the spatial dimension of sustainability. It also develops a logically consistent conceptual framework for the analysis and evaluation of sustainable development, following a spatial systems approach. Five interconnected aspatial subsystems or subsets of a spatial system are identified and their respective operational dimensions discussed. A proposed composite index calleddegree of stainable development (DSD) and its five component indicators are also outlined. The difficulties involved in operationalizing the DSD measure and the conceptual framework are noted, and the various tasks that need to be undertaken in this regard are specified. It is concluded that future research utilizing the proposed conceptual framework should not only foster the development of appropriate methodologies for the comparative evaluation of sustainable development at global, national, or regional scales, but also offer insights to appropriate decision makers at various levels regarding available options and alternative actions for the healthy development of their respective societies.     

高碘酸钾氧化中性红测定间苯二酚

在酸性和75℃条件下,微量的间苯二酚对高碘酸钾氧化中性红褪色反应具有显著的抑制作用,据此建立了测定间苯二酚的新的动力学光度法。该方法灵敏、快速、操作简便,此法的线性范围为0．1～3．0μg／mL,检出限为0．082μg／mL,对1．0μg／mL的间苯二酚测定11次的相对标准偏差为2．26％。     

新常态下如何实现环境保护的纳什均衡

从自然资源和生态环境的公共性出发,认为以经济建设为中心的政策选择,促成了以淡视生态环境为前提的均衡策略,让经济发展与环境保护之间形成"坏"的纳什均衡,而新常态能够为经济发展和环境保护之间达成好的纳什均衡提供了改革保障、法制保障和经济保障,因此,新常态下的生态文明建设能够解套环境保护的"囚徒困境",最重要的任务是借助政府这一外力制定新的"游戏规则",以打破原有的"纳什均衡",通过建立健全环境成本内部化的政策措施和生态补偿机制、改革政绩考核机制实现对绿色发展的激励等措施,推进经济发展与环境保护之间达成理想的"纳什均衡"。     

Land Degradation Evaluation in North Hebei Province Based on Remote Sensing and GIS

Abstract

Land degradation is one of the serious environmental problems that can lead to poverty, and is especially prominent in eco-fragile areas in developing countries and increases the risk of environmental safety. North Hebei Province belongs to an ecologically fragile region in North China, which has great impact on the eco-safety of Beijing and Tianjin. Using Landsat TM data and GIS, this paper evaluates land degradation in North Hebei province of China from the the 1960's to 1987 and 2000. Land use/cover change pattern from 1987 to 2000, its regional difference and forest change characteristics will also be analyzed; soil erosion intensity and arable land suitability were also evaluated. Results revealed that land use/cover pattern in this study area did not change greatly from 1987 to 2000. The structure and function of regional land ecosystem was at a level of local improvement and integral deterioration. Land above medium soil erosion intensity reached 21 percent, which was also the area with a serious soil erosion and land degradation problem. Soil erosion and land degradation intensity of grassland was the biggest. For the present arable land, the proportion of high suitability was 13 percent.