Transport development bring a negative impact on human survival ecological environment, such as destruction of vegetation, air pollution, soil erosion and other environmental issues.The actuality proves that the use of tunnel development of underground space can improve traffic quality, while also protecting the environment.Therefore, tunnel engineering and utilization of undergrotmd space are to protect the ecological environment to be effective ways for realizing economic sustainable development of economy.In this paper, based on the practical application at home and abroad, for the big cities, mountain areas, river waters, the suitability evaluation and beneficial discussion about the transportation by using tunnel to protect the ecological environment are of great practical significance to protect and improve the ecological environment.

关键词：大气；生态环境；大气污染

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The U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office (NNSA/NFO) operates the Nevada National Security Site (NNSS) and North Las Vegas Facility (NLVF). From 1951 through 1992, the NNSS was the continental testing location for U.S. nuclear weapons. The release of radionuclides from NNSS activities has been monitored since the initiation of atmospheric testing. Limitation to underground detonations after 1962 greatly reduced radiation exposure to the public surrounding the NNSS. After nuclear testing ended in 1992, NNSS radiation monitoring focused on detecting airborne radionuclides from historically contaminated soils. These radionuclides are derived from re-suspension of soil (primarily by wind) and emission of tritium-contaminated soil moisture through evapotranspiration. Low amounts of legacy-related tritium are also emitted to air at the NLVF, an NNSS support complex in North Las Vegas. To protect the public from harmful levels of man-made radiation, the Clean Air Act, National Emission Standards for Hazardous Air Pollutants (NESHAP) (Title 40 Code of Federal Regulations (CFR) Part 61 Subpart H) (CFR 2010a) limits the release of radioactivity from a U.S. Department of Energy (DOE) facility to that which would cause 10 millirem per year (mrem/yr) effective dose equivalent to any member of the public. This limit does not include radiation unrelated to NNSS activities. Unrelated doses could come from naturally occurring radioactive elements, from sources such as medically or commercially used radionuclides, or from sources outside of the United States, such as the damaged Fukushima nuclear power plant in Japan in 2011.

关键词：大气；有害气体；大气污染

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As airport operations continue to expand as infrastructure is modified to meet the growing demand for air travel, they need to balance their growth with environmental constraints. Although the main environmental concern continues to be noise, a more comprehensive approach needs to be implemented to better understand the effects of airport growth and changes. Indeed, the implementation of new aircraft and navigation technologies under the Next Generation Air Transportation System (NextGen) will require both noise and emissions, as well as fuel burn, to be assessed in order to fully understand the effects from such complex new technologies.

关键词：大气；空气污染；空气优化

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Anthropogenic sources of air pollution emissions include a number of sectors and activities e.g., fossil fuel and biofuel combustion in industrial and residential areas, transportation (road, rail, air and ships), waste disposal, industrial processes, agricultural activities, solvent production and usage. Emissions of greenhouse gases (GHGs), such as Carbon dioxide (CO_2), methane (CH_4) and nitrous oxide (N_2O) are a major concern from climate change perspective. This because they obstruct the escape of infrared (heat) energy to outer space by absorbing them and leading to increase in earth's temperature along with other climatic changes (Bond et al. 2004). Anthropogenic activities annually attribute to an estimated 3%, 64%, and 24% of global emissions of CO_2, CH4 and N_2O, respectively (Duxbury 1994). Megacities contribute a major portion in these global emissions. As reported by Butler et al. (2008) megacities account for approximately between 9% and 12% of the global emissions of CO, NO_X, and NMVOC.

关键词：大气；温室气体；环境保护

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There are large amount of ammonia in coking wastewater.It is a good recycling desulfurizer.Sintering flue gas has the characteristics,such as large amount of,low SO2 concentration,great changes of operation load.Treating sintering flue gas with coking wastewater can attain the destination of treating waste with waste.This paper adopts a spray tower countercurrent device,and SO2 concentration in the entrance and exit flue gas is on line detected by an automatic flue gas detection instrument.The paper studies on the change rule of SO2 concentration in the process of treating sintering flue gas using coking wastewater,and the influence of SO2 initial concentration in sintering flue gas to the desuifurization rate.The results show that after being treated the sintering flue gas can reach the emission standard for air pollutants of iron and steel industry.

关键词：大气；焦化废水；大气污染

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Catalytic processes are today practiced on a vast scale to convert basic feedstocks (today largely petroleum, gas, and coal based) into fuels, plastics, agricultural chemicals, pharmaceuticals, foods, paints/coatings, and numerous other materials that underpin our economy and well-being. Catalysts are also used extensively to provide a cleaner environment by treating automotive and industrial (e.g., power plant) exhausts and water-borne effluents. Indeed, it has been estimated that more than 50% of the US GDP derives from catalytic processes. In the past several years, it has become apparent that the US energy supply and demand picture has shifted dramatically, and that a major scientific research and development effort must be mounted to maintain US economic leadership and our quality of life. The challenges are to use and convert more abundant, lower cost/lower quality, and more sustainable feedstocks into the products we need with unprecedented energy- and atom-efficiency. The need to develop more efficient, cleaner and greener catalytic processes is grand challenge of national import.

关键词：大气；气体净化；空气健康

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Environmental concerns have led to numerous regulations that have dramatically decreased the reported production and use of mercury in the United States since the 1980s. Government legislation and subsequent industry actions have led to increased collection of mercury-containing materials and the recovery of mercury through recycling. Mercury emissions have been reduced and effective alternatives to mercury products have been developed for many applications. This study updates and quantifies the changes in demand, supply, use, and material flow for mercury in various sectors in the United States that have taken place since 1996.

关键词：大气；废气转化；环境保护

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Energy-related carbon dioxide (CO2) emissions in 2012 were the lowest in the United States since 1994, at 5.3 billion metric tons of CO2 (see figure above). With the exception of 2010, emissions have declined every year since 2007.

关键词：大气；温室气体；环境保护

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This paper is a deliverable on a technical support task for the FHWA Office of Operations. The objective of the task is to develop white papers on emerging and current topics of interest to the Office. Topics for white papers were primarily identified and prioritized based on internal listening sessions with Office of Operations personnel. This white paper presents various effects of climate change, and how those effects will impact transportation system management and operations. Also presented are presents various options for agencies to assess the vulnerabilities of transportation systems and proposed changes to make transportation operations more resilient to climate change.

关键词：大气；气候变化；空气治理

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On April 15, 2011, NIOSH received an employee request regarding headaches, fatigue, weakness, fever, chills, flu-like symptoms, shortness of breath, coughing, chronic sinusitis, sore throat, burning eyes, and difficulty concentrating in a water-damaged building. In June 2011, NIOSH investigators conducted a site visit. The majority of employees reported building-related symptoms. We found evidence of water damage inside the building and mold inside supply air ducts of two air handlers. Vacuumed carpet dust samples collected during the site visit showed a high burden of culturable fungi and bacteria. We provided a number of recommendations for remediation including addressing causes of water damage and replacing contaminated carpet and ductwork. Building management replaced two rooftop air handling units and some ductwork. The carpet was steam cleaned. Some building occupants continued to have symptoms, and the accounting company relocated to another building.

关键词：大气；室内空气；空气质量

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