Application of surface molecular imprinting adsorbent in expanded bed for the adsorption of Ni(2+) and adsorption model

A new surface molecular imprinting adsorbent (SMIA) was used in an expanded bed. The expansion ratio and adsorption performance were studied at different volumetric rates, inlet concentrations, and pH values. A model based on the Adams-Bohart adsorption model of breakthrough curves was established. The predicted curves had good agreement with the experimental curves. The breakthrough time (T(1/2)) decreased with increasing inlet concentration when the outlet concentration was half the initial concentration (C/C(0)=0.5). The inlet concentration had little effect on the adsorption rate constant (k(1)) value when the initial concentration (C(0)) was above 150 mg/L. However, T(1/2) values increased with increasing initial pH of the inlet solution, and the k(1) value decreased due to the competition between H(+) and Ni(2+).     

Impact assessment of waste management options in Singapore

This paper describes the application of life cycle assessment for evaluating various waste management options in Singapore, a small-island city state. The impact assessment method by SimaPro is carried out for comparing the potential environmental impacts of waste treatment options including landfilling, incineration, recycling, and composting. The inventory data include gases and leachate from landfills, air emissions and energy recovery from incinerators, energy (and emission) savings from recycling, composting gases, and transport pollution. The impact assessment results for climate change, acidification, and ecotoxicity show that the incineration of materials imposes considerable harm to both human health and the environment, especially for the burning of plastics, paper/cardboard, and ferrous metals. The results also show that, although some amount of energy can be derived from the incineration of wastes, these benefits are outweighed by the air pollution (heavy metals and dioxins/furans) that incinerators produce. For Singapore, landfill gases and leachate generate minimal environmental damage because of the nation's policy to landfill only 10% of the total disposed wastes. Land transportation and separation of waste materials also pose minimal environmental damage. However, sea transportation to the landfill could contribute significantly to acidification because of the emissions of sulfur oxides and nitrogen oxides from barges. The composting of horticultural wastes hardly imposes any environmental damage. Out of all the waste strategies, the recycling of wastes offers the best solution for environmental protection and improved human health for the nation. Significant emission savings can be realized through recycling.     

Persistent organic pollutants in moss as bioindicators of atmospheric pollution in Singapore

Moss samples were collected from the island of Singapore and analysed for a range of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). Although all compounds analysed have been banned from use in Singapore, they were detected in all samples collected. Among the hexachlorocyclohexanes (HCH), beta-HCH was the most dominant isomer, while trans-chlorane was found to be the most dominant cyclodiene pesticide. High levels (79.12 ng g(-1)) of PCBs were detected in mosses collected from a nearby island due to active accumulation of pollutants associated with boat emissions. Significant spatial variations in the levels of organic pollutants in Singapore were largely absent, indicating that air masses moving over the island deposit OCPs and PCBs in a uniform pattern. A comparison of moss pollutant levels with available data from Czech Republic showed that dichlorodiphenyldichloroethylene (p,p'-DDE), dichlorodiphenyltrichloroethane (p,p'-DDT) and PCB levels in Singapore are the highest. The presence of these compounds suggests that they are still used in the region and are environmentally recalcitrant.     

汽车碰撞模拟装置加速度测试

在安全气囊的关键部件——气体发生器的产气性能测试试验中,加速度是一个重要的被测参数.采用1套台架冲击实验装置模拟汽车碰撞过程.通过调节提升高度和弹性缓冲物来使碰撞加速度峰值和碰撞持续时间满足气体发生器产气性能测试试验的要求.     

Empirical analysis on contribution share of safety investment to economic growth: A case study of Chinese mining industry

Insufficient investment in safety is one of the most important reasons which lead to frequent accidents in Chinese mining industry. Safety input has long been regarded as a ‘sunk cost’, lacking output, and little attention from mining companies was focused on increasing safety input according to technical codes or technical requirements due to the narrow understanding on safety input. So, the empirical analysis on the contribution share of safety investment to economic growth is very important. In this paper, a new set of production safety indexes including six 1-level indexes for describing the safety level of mining production in China was constructed on the basis of Granger causality test. Meanwhile, a mining economic growth model was constructed on the basis of the new production safety indexes with co-integration theory and dynamic modeling system. The empirical results show that the production safety factor in the short term indeed drives the GDP growth in the mining industry although labor and capital input remain the major factors impacting mining economic growth, and its long term contribution share is 7.7%. Principal Component Analysis (PCA) of production safety indexes, shows that the safety level of mining production increased more than 21-fold during 1991–2009, and the investment in mining technology development capability, mining safety production environment and mechanized level of mining should be the direction to focus for improving the safety level of mining production.     

Research on the technology of detection and risk assessment of fire areas in gangue hills

Environmental Science and Pollution Research - Coal gangue hills are prone to spontaneous combustion, thereby polluting the environment of mining areas such as the soil, groundwater, and...     

Mitigating the impact of oil‐palm monoculture on freshwater fishes in Southeast Asia

Anthropogenic land‐cover change is driving biodiversity loss worldwide. At the epicenter of this crisis lies Southeast Asia, where biodiversity‐rich forests are being converted to oil‐palm monocultures. As demand for palm oil increases, there is an urgent need to find strategies that maintain biodiversity in plantations. Previous studies found that retaining forest patches within plantations benefited some terrestrial taxa but not others. However, no study has focused on aquatic taxa such as fishes, despite their importance to human well‐being. We assessed the efficacy of forested riparian reserves in conserving freshwater fish biodiversity in oil‐palm monoculture by sampling stream fish communities in an oil‐palm plantation in Central Kalimantan, Indonesia. Forested riparian reserves maintained preconversion local fish species richness and functional diversity. In contrast, local and total species richness, biomass, and functional diversity declined markedly in streams without riparian reserves. Mechanistically, riparian reserves appeared to increase local species richness by increasing leaf litter cover and maintaining coarse substrate. The loss of fishes specializing in leaf litter and coarse substrate decreased functional diversity and altered community composition in oil‐palm plantation streams that lacked riparian reserves. Thus, a land‐sharing strategy that incorporates the retention of forested riparian reserves may maintain the ecological integrity of fish communities in oil‐palm plantations. We urge policy makers and growers to make retention of riparian reserves in oil‐palm plantations standard practice, and we encourage palm‐oil purchasers to source only palm oil from plantations that employ this practice.     

A weighted fuzzy linear programming model in economic input–output analysis: an application to risk management of energy system disruptions

Climate change exposes economic systems to numerous risks, including reduced agricultural production and electric power supply shortages. The interdependent nature of economic systems causes disruptions in any sector to cascade to other sectors via forward and backward linkages. This work develops an optimization model with which allocation of scarce goods or resources can be optimized; the model uses an overall index of satisfaction of fuzzy economic output goals under conditions of scarcity caused by climatic disruptions. The proposed model includes a vulnerability measure that integrates information elicited from expert judgment. A case study based on a scenario of drought-induced electricity shortage in the Philippine economy is examined. Results show that trade, transportation and service-oriented industries suffer losses in gross domestic product in the Philippine case.     

A comparison of municipal solid waste management in Berlin and Singapore

A comparative analysis of municipal solid waste management (MSWM) in Singapore and Berlin was carried out in order to identify its current status, and highlight the prevailing conditions of MSWM. An overview of the various aspects of MSWM in these two cities is provided, with emphasis on comparing the legal, technical, and managerial aspects of MSW. Collection systems and recycling practiced with respect to the involvement of the government and the private sector, are also presented.Over last two decades, the city of Berlin has made impressive progress with respect to its waste management. The amounts of waste have declined significantly, and at the same time the proportion that could be recovered and recycled has increased. In contrast, although Singapore’s recycling rate has been increasing over the past few years, rapid economic and population growth as well as change in consumption patterns in this city-state has caused waste generation to continue to increase. Landfilling of MSW plays minor role in both cities, one due to geography (Singapore) and the other due to legislative prohibition (Berlin). Consequently, both in Singapore and Berlin, waste is increasingly being used as a valuable resource and great efforts have been made for the development of incineration technology and energy recovery, as well as climate protection.     

Life cycle assessment of sewage sludge co-incineration in a coal-based power station

A life cycle assessment was conducted to evaluate the environmental and economic effects of sewage sludge co-incineration in a coal-fired power plant. The general approach employed by a coal-fired power plant was also assessed as control. Sewage sludge co-incineration technology causes greater environmental burden than does coal-based energy production technology because of the additional electricity consumption and wastewater treatment required for the pretreatment of sewage sludge, direct emissions from sludge incineration, and incinerated ash disposal processes. However, sewage sludge co-incineration presents higher economic benefits because of electricity subsidies and the income generating potential of sludge. Environmental assessment results indicate that sewage sludge co-incineration is unsuitable for mitigating the increasing pressure brought on by sewage sludge pollution. Reducing the overall environmental effect of sludge co-incineration power stations necessitates increasing net coal consumption efficiency, incinerated ash reuse rate, dedust system efficiency, and sludge water content rate.