The pyrolysis of sawdust and polyethylene in TG and U-shape tube reactor

The co-pyrolysis of sawdust and polyethylene was carried out in a TG-DTG system and a U-shape tube reactor. This research was focused on the interaction between sawdust and polyethylene during the pyrolysis process. The results showed that the interaction between the sawdust particles and polyethylene particles could be ignored during the devolatile process, but there was interaction among the volatile components in the co-pyrolysis process.     

秦沈客运专线工程建设办公信息系统的安全设计

从秦沈客运专线工程建设办公信息系统的网络和系统内部安全机制出发 ,提出了大型交通工程项目办公自动化系统信息安全技术的理论和设计思路。系统而成功的运行为今后同类项目的安全设计提供了一种新的思路并有一定的参考价值。     

Sustainability assessment of national rural water supply program in Tanzania

Sustainability of rural water supply programs in developing countries is still an elusive goal. It is widely accepted that, as a rule, they have failed to deliver benefits to society in the long run. Emphasis has frequently been placed on the short‐term activities. Fast production of new schemes is thus a common strategy, prioritizing the engineering component, while sidestepping social and participatory issues and community empowerment. In 2006, the Government of Tanzania launched a national program to meet water sector targets set out in the Millennium Development Goals by the year 2015. In this study we evaluate key features of the program on a sustained basis. There is evidence that the Government is promoting more sustained facilities, focusing on cost recovery and on ‘decentralization by devolution’. Nevertheless, there are several shortcomings which threaten the long‐term functionality of the infrastructure that has to be built. In light of the implementation of the program, and based on the outputs of its pilot phase, we review the factors that can determine its sustainability.     

Monitoring trace metals in urban aerosols from Buenos Aires city. Determination by plasma-based techniques

A study was undertaken, within the framework of a 3 years national project, to assess the content of 13 elements in airborne particulate matter collected in representative zones of the metropolitan area of Buenos Aires. The sampling strategy followed consisted in collecting simultaneously 67 samples of PM10 particulate matter in 9 sampling sites covering an area of about 30 km2 during one week. The collection was performed on ash-free fibre-glass filters using high volume samplers. A combination of aqua regia and perchloric acid was used for leaching metals from filters. Key elements, namely Al, Ca, Cu, Fe, Mn, Mo, Ni, Pb, S, Sb, Sn, Zn and Zr, were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS) at micro g g(-1) and ng g(-1) levels. Analyte concentration varied from 130 ng g(-1)(Mo) to over 30%(Ca). Multivariate statistical analysis was performed on the data set including the measured elemental compositions for the monitored period. The atmospheric concentration found for Pb confirms the decreasing levels of this element since the introduction of unleaded gasoline in 1995: 88 ng m(-3)(2001) < 220 ng m(-3)(1997) < 3900 ng m(-3)(1994). The average S concentration above 3 microg m(-3) is somehow unexpectedly high for Buenos Aires since the relatively low S content of liquid fuels and the massive usage of natural gas imply low emissions of this element from combustion activities. To the best of our knowledge, S concentrations are reported for the first time for this city.     

Two-Stage Fuzzy-Stochastic Robust Programming: A Hybrid Model for Regional Air Quality Management

Abstract

In this study, a hybrid two-stage fuzzy-stochastic robust programming (TFSRP) model is developed and applied to the planning of an air-quality management system. As an extension of existing fuzzy-robust programming and two-stage stochastic programming methods, the TFSRP can explicitly address complexities and uncertainties of the study system without unrealistic simplifications. Uncertain parameters can be expressed as probability density and/or fuzzy membership functions, such that robustness of the optimization efforts can be enhanced. Moreover, economic penalties as corrective measures against any infeasibilities arising from the uncertainties are taken into account. This method can, thus, provide a linkage to predefined policies determined by authorities that have to be respected when a modeling effort is undertaken. In its solution algorithm, the fuzzy decision space can be delimited through specification of the uncertainties using dimensional enlargement of the original fuzzy constraints. The developed model is applied to a case study of regional air quality management. The results indicate that reasonable solutions have been obtained. The solutions can be used for further generating pollution-mitigation alternatives with minimized system costs and for providing a more solid support for sound environmental decisions.     

Evolution of China’s water issues as framed in Chinese mainstream newspaper

There is an urgent need globally to trigger fundamental societal changes in water management away from existing unsustainable paradigms. This paper attempts to understand the evolution of newspaper coverage of water issues in China by analyzing water-related articles in a major national newspaper, the People’s Daily, over the period 1946–2012 using a content analysis approach. The major findings include the following: (1) water issues were in relatively prominent positions in the newspaper; (2) the reporting of water issues in China experienced three stages: 1946 to the middle of 1980s—flood and drought control and water for food production, the middle of 1980s to 1997—water for economic development, and 1998 to the present—water for the environmental sustainability and economic development; (3) the reporting of water issues in the People’s Daily clearly reflected China’s top-down water resources management system, and no “real” public opinions on water were reported during the study period; and (4) the People’s Daily is just a wind vane of Chinese mainstream values and policies on water. The findings supported the realist assumption that the societal value changes on water issues in China were triggered by a range of factors including biophysical pressure (floods and droughts), political campaign (the Cultural Revolution), macro-economic reform (Reform and Opening-up), water institutional arrangement (the Water Law), and water management reform (the No. 1 Central Document on water reform). While there are similarities and differences between this study and other studies, important implications for more sustainable water management are a need to strengthen academic specialists’ and NGO’s voices in the newspaper to create a better informed public, and to stimulate practices toward sustainable water use.     

焊接作业中尘毒的危害与对策

介绍了焊接作业中有害气体对作业人员身体的危害,同时论述了有害气体烟尘的来源、种类及危害情况,介绍了防护措施。     

Using the sustainable development goals towards a better understanding of sustainability challenges

The United Nations General Assembly agreed and approved in September 2015 the document ‘2030 Agenda for Sustainable Development’, which contains a set of measures aiming to balance economic progress and protection of the environment, whilst at the same time remain aware of the need to address the many disparities still seen between industrialised and developing countries. The Agenda document consists of 17 Sustainable Development Goals (SDGs), which among many other tasks, intend to eradicate poverty and create better health conditions in both developed and developing countries. But despite the need for and the relevance of the SDGs, it is unclear how they may help to address present and future sustainability challenges. Based on the need to shed some light on such a relationship, this paper describes each of the SDGs, and offers an analysis of the extent to which their implementation may offer support to ongoing attempts to handle some of the pressing problems seen in pursuing sustainable development. Three case studies are presented to show in practice how best the SDGs can be handled. The paper concludes that the process of implementing the SDGs offers unrivalled opportunities to advance equal opportunity and foster economic empowerment, helping countries to promote the cause of sustainable development in their territories, hence benefiting their populations.     

Ecosystem management based on ecosystem services and human activities: a case study in the Yanhe watershed

With activities that alter the structure and function of the habitat, humans have a direct impact on ecosystems and ecosystem services, i.e., the conditions and processes that sustain human life. In this study, 35 townships in the Yanhe watershed in the Loess Plateau of China were selected. The net primary production (NPP), carbon sequestration and oxygen production (CSOP), water conservation, and soil conservation were the ecosystem services selected and valuated. Human activity was quantified by an integrated human activity index (HAI) based on population density, farmland ratio, and the influence of road networks and residential areas. The NPP, CSOP, and water conservation showed a conspicuous spatial pattern fanning outward from the southwest, while the soil conservation showed an obscure spatial pattern distinguished primarily by the peripheral area surrounding the urbanized areas. Total ecosystem services in the Yanhe watershed demonstrated a decreasing pattern from south to north, and the HAI was in proportion to administrative and economic development. Based on the selected ecosystem services and HAI, we mapped the townships of the Yanhe watershed by cluster analysis, and provided sustainable ecosystem management suggestions, tailored to the social-ecological map.     

EVALUATION OF Ann AGNPS NITROGEN LOADING IN AN AGRICULTURAL WATERSHED1

ABSTRACT: Pollutants entering a water system can be very destructive to the health of that system. Best Management Practices (BMPs) are used to reduce these pollutants, but understanding the most effective practices is very difficult. Watershed models are an effective tool to aid in the decision‐making process of selecting the BMPs that are most effective in reducing the pollutant loading and are also the most cost effective. The Annualized Agricultural Nonpoint Source Pollution model (AnnAGNPS 2.0) is a technological tool that can be used to estimate watershed response to agricultural management practices. The main purpose of this paper is to test the performance of AnnAGNPS 2.0 on nitrogen loading using comparisons with measurements from the Deep Hollow watershed of the Mississippi Delta Management Systems Evaluation Area (MDMSEA) project. Previous work has demonstrated the capability of the model to simulate runoff and sediment. From sensitivity analyses in this study, initial nitrogen concentration in the soil and crop nitrogen uptake had the most impact on the nitrogen loadings. AnnAGNPS simulations of monthly nitrogen loadings are poor. However, statistical test (t‐test) showed that the predicted nitrogen loading is not significantly different from observed nitrogen loading at the 95 percent level of confidence.