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611.
Over the past decade, the assessment of human systems interactions with the environment has permeated all phases of environmental and public health research. We are invoking lessons learned from the broad discipline of Systems Biology research that focuses primarily on molecular and cellular networks and adapting these concepts to Systems Exposure Science which focuses on interpreting the linkage from environmental measurements and biomonitoring to the expression of biological parameters. A primary tool of systems biology is the visualization of complex genomic and proteomic data using “heat maps” which are rectangular color coded arrays indicating the intensity (or amount) of the dependent variable. Heat maps are flexible in that both the x-axis and y-axis can be arranged to explore a particular hypothesis and allow a fast overview of data with a third quantitative dimension captured as different colors. We are now adapting these tools for interpreting cumulative and aggregate environmental exposure measurements as well as the results from human biomonitoring of biological media including blood, breath and urine. This article uses existing EPA measurements of environmental and biomarker concentrations of polycyclic aromatic hydrocarbons (PAHs) to demonstrate the value of the heat map approach for hypothesis development and to link back to stochastic and mixed effects models that were originally used to assess study results.  相似文献   
612.
This research is part of the SPIn-Eco project for the Province of Siena, Italy, and applies an environmental accounting method to a region with reference to its population, human activities, natural cycles, infrastructures and other settings. This study asserts that the consumption of resources due to the human economy is a source of great concern because of the load it places on the biosphere. Environmental resources locally used, whether directly or indirectly, from both renewable energy fluxes and storage of materials and energies, are investigated. In this paper emergy analysis is presented and applied to the Province of Siena and to each of its municipalities, in order to evaluate the main flows of energy and materials that supply the territorial system, including human subsystems, with reference to their actual environmental cost. Therefore, the behaviour of the whole system and the interactions between natural and human agents were studied; in other words, the attitudes of the territorial systems toward resource use as revealed by their patterns of emergy consumption were observed. Once expressed in units of the same form of energy through the emergy evaluation, categories of resource consumption and systems of varying scales and organization are compared. Furthermore, indexes of environmental performance based on emergy are calculated. Flows of energy and materials are assessed, and their intensities, which vary throughout the area of the Province, are then visualized on maps.  相似文献   
613.
Life cycle assessment (LCA) can be successfully applied to municipal solid waste (MSW) management systems to identify the overall environmental burdens and to assess the potential environmental impacts. In this study, two methods used for current MSW management in Phuket, a province of Thailand, landfilling (without energy recovery) and incineration (with energy recovery), are compared from both energy consumption and greenhouse gas emission points of view. The comparisons are based on a direct activity consideration and also a life cycle perspective. In both cases as well as for both parameters considered, incineration was found to be superior to landfilling. However, the performance of incineration was much better when a life cycle perspective was used. Also, landfilling reversed to be superior to incineration when methane recovery and electricity production were introduced. This study reveals that a complete picture of the environmental performance of MSW management systems is provided by using a life cycle perspective.  相似文献   
614.
Extensive information on the greenhouse impacts of various human actions is important in developing effective climate change mitigation strategies. The greenhouse impacts of combustible fuels consist not only of combustion emissions but also of emissions from the fuel production chain and possible effects on the ecosystem carbon storages. It is important to be able to assess the combined, total effect of these different emissions and to express the results in a comprehensive way. In this study, a new concept called relative radiative forcing commitment (RRFC) is presented and applied to depict the greenhouse impact of some combustible fuels currently used in Finland. RRFC is a ratio that accounts for the energy absorbed in the Earth system due to changes in greenhouse gas concentrations (production and combustion of fuel) compared to the energy released in the combustion of fuel. RRFC can also be expressed as a function of time in order to give a dynamic cumulative picture on the caused effect. Varying time horizons can be studied separately, as is the case when studying the effects of different climate policies on varying time scales. The RRFC for coal for 100 years is about 170, which means that in 100 years 170 times more energy is absorbed in the atmosphere due to the emissions of coal combustion activity than is released in combustion itself. RRFC values of the other studied fuel production chains varied from about 30 (forest residues fuel) to 190 (peat fuel) for the 100-year study period. The length of the studied time horizon had an impact on the RRFC values and, to some extent, on the relative positions of various fuels.  相似文献   
615.
典型重金属污染农田能源植物示范种植研究   总被引:10,自引:0,他引:10       下载免费PDF全文
为探索安全经济利用重金属中度-重度污染农田的模式,在浙江某典型重金属复合污染农田开展了能源植物(甜高粱Sweet sorghum、甘蔗Saccharum sinensisRoxb.、香根草Vetiveria和盐肤木Rhus chinensis)种植示范研究.结果表明,经施加0.1%的石灰和0.2%的磷矿粉改良后,土壤p...  相似文献   
616.
This paper analyses whether China's export VAT rebates and export taxes are driven by environmental concerns. Since China struggles to enforce environmental regulation, trade policy can be used as a second-best environmental policy. In a general equilibrium model it is possible to show that the second-best export tax increases in a product's pollution intensity. The empirical analysis investigates whether the export tax equivalent of partial VAT rebates and export taxes are higher for products which are more pollution intensive along several dimensions. The results indicate that the VAT rebate rates are set in a way that discourages exports of water pollution intensive, SO2 intensive and energy intensive products from 2007 on. Moreover, the conservation of natural resources such as minerals, metals, wood products and precious stones seems to be a key determinant of China's export VAT rebate rates. There is little evidence that export taxes are motivated by environmental concerns.  相似文献   
617.
This paper describes a four-year programme of “action research” (AR) undertaken with six communities in the UK, referred to as the Evaluating Low-Carbon Communities (EVALOC) project. The research combined a programme of research events with phased household-level monitoring of energy and carbon-reduction interventions. The carbon-reduction interventions were funded by the UK’s Department of Energy and Climate Change prior to the onset of the research. AR has recently been adopted within the context of environmental behaviour change programmes in the UK, with a number of methodological challenges. The EVALOC project’s challenges included developing a collaborative research design; building reciprocity between the researchers and research participants; dealing with biases and burdens in the research process; ensuring analytical rigour in the interpretation of the primarily qualitative evidence and dealing with the long-term and process-driven outcomes that arise from such interactions. This paper explores and discusses the challenges of AR in relation to selected research outcomes from EVALOC. We conclude by suggesting that the AR approach has helped to build capacity in the participating low-carbon communities (LCCs), through supporting the design, delivery and evaluation of their energy and carbon-reduction activities.  相似文献   
618.
In this study, the optimal sizing and performance analysis of a standalone integrated solar power system equipped with different storage scenarios to supply the power demand of a household is presented. One of the main purposes when applying solar energy resource is to face the increasing environmental pollutions resulting from fossil fuel based electricity sector. To this end, and to compare and examine two energy storage technologies (battery and hydrogen storage technology), three storage scenarios including battery only, hydrogen storage technology only and hybrid storage options are evaluated. An optimization framework based on Energy Hub concept is used to determine the optimum sizes of equipment for the lowest net present cost (NPC) while maintaining the system reliability. It was determined that the most cost effective and reliable case is the system with hybrid storage technology. Also, the effects of solar radiation intensity, the abatement potential of CO2 emissions and converting excess power to hydrogen on the system’s performance and economics, were investigated and a few noticeable findings were obtained.  相似文献   
619.
介绍了某电厂300 MW机组FGD装置在相同试验工况安排下分别使用三家公司提供的脱硫增效剂的试验情况,其脱硫率均有不同程度的提升,钙硫比显著降低,石膏浆液及石膏产品品质有所提高.说明使用脱硫增效剂后,在正常运行负荷范围内,不仅能优化系统参数,而且可以停一台浆液循环泵运行,降低系统电耗.  相似文献   
620.
We estimate the Marginal Cost of Public Funds (MCPF) for Peru using a detailed computable general equilibrium (CGE) model. Revenues from all major sources (including taxes on factors of production, natural resources such as energy and minerals, consumption, and imports) are examined. Our focus is on the efficiency implications of mineral and energy taxes, given their importance to Peruvian public finance. The primary data are from the Global Trade Analysis Project (GTAP) as modified to include detailed tax information from the Peruvian Ministry of Economy and Finance and the Peruvian Internal Revenue Service. Consistent with the theories of public finance, we find that the MCPF is greater for activities that face high or widely varying tax rates. The taxes on energy and mineral activities represent a clear illustration of this relationship. The results presented in this paper indicate opportunities to improved efficiency in the current tax mix, and also indicate the financing costs of proposed expenditures that would be funded with taxes on energy and natural resources.  相似文献   
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