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681.
Mark K. Goldstein Salvador R. Bozzo Robert Malone Fernando Galdos Walter Sevian Donald Goellner 《Environmental management》1979,3(5):447-460
The data base for each process of the nuclear fuel cycle has been updated as a part of the Committee on Nuclear and Alternative Energy Systems (CONAES) at Brookhaven National Laboratory (BNL). The BNL Energy System Network Simulator (ESNS) was modified to accommodate the new data, and methodology was developed for estimating population dose and health effects resulting from atmosphere releases of radioactive materials from the nuclear fuel cycle.Estimates of population dose and health effects were made using these new CONAES emission data and the new model for three scenarios out to the year 2000: (1) no reprocessing; (2) reprocessing, 1-year cooling; and (3) reprocessing, 5-year cooling. Results indicate that radon emissions from mining and milling of uranium bearing ores will have greater impacts than any other component in the open nuclear fuel cycle. The estimated number of health effects will depend, to a large extent, on the lung model mechanism assumed to induce cancer; i.e., either the smeared or the unsmeared model. The smear model and the linear relationship predict for scenario 1, 630; for scenario 2, 949; and for scenario 3, 854 lung cancers, respectively, using the new CONAES data.Epidemiologic data from six United States counties were correlated using a new statistical model (described in the text) in order to test the validity of the lung model and the linear relationship. Results do not support the high lung cancer correlations expected from the unsmear model and the linear relationship; therefore, it is concluded that low-dose mechanisms may be different from those developed from high-dose data. The best place to look for effects of low-dose radiation may be the less developed countries because of a reduction in the noise level caused by chemical pollutants. 相似文献
682.
683.
汽车代用燃料及应用前景 总被引:4,自引:0,他引:4
介绍了已经开发使用的代用燃料氢气,甲醇,乙醇,新配方汽油,天然气,液化石油气,电动汽车等,并对代用燃料车和汽油车的环境安全性,成本,能耗消耗等方面作了比较,指出天然气,液化石油气是当前最有前途的代用燃料。 相似文献
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685.
发动机燃料组分生烟特性的研究 总被引:3,自引:0,他引:3
本文采用火焰高度测定仪系统地评价了构成发动机燃料的单体烃和单体醇的生烟特性,提出并应用碳烟生成的烃正离子概念解释了单体烃和单体醇的生烟规律,为正确调整发动机燃料构成提供了实践基础,也为研究和开发消烟助燃剂奠定了理论基础。 相似文献
686.
687.
The low-heat-value cornstalk gas produced in the down-flow fixed bed gasifier was tentatively used for methanol synthesis. The cornstalk gas was purified and the technical procedures such as deoxygenation, desulfurization, catalytic cracking of tar, purification and hydrogenation were studied. The catalytic experiments of methanol synthesis with cornstalk syngas were carried out in a tubular-flow integral and isothermal reactor. The effect of reaction temperature, pressure, catalysttypes, catalyst particle size, syngas flow at entering end and composition of syngas was investigated. The optimum process conditions and yield of methanol from cornstalk syngas were obtained. The experimental results indicated that the proper catalyst of the synthetic reaction was C301 and the optimum catalyst size (φ) was 0.833 mm×0.351 mm. The optimum operating temperature and pressure were found to be 235℃ and 5 Mpa, respectively. The suitable syngas flow 0.9-1.10 mol/h at entering end was selected and the best composition of syngas were CO 10.49%, CO2 8.8%, N2 37.32%, CnHm 0.95% and H2 40.49%. The best methanol yield is 0.418 g/g cornstalk. The study provided the technical support for the industrial test of methanol production from biomass (cornstalk)gas. 相似文献
688.
The direct urea fuel cell (DUFC) is a low cost and competitive approach for contemporaneous urine or urea-contaminated wastewater treatment and electricity generation. However, the lack of efficient urea oxidation reaction (UOR) electrocatalysts and suitable electron acceptors remains a challenge for practical applications. Here, we developed a DUFC system using Ni2[email protected] foam as the anode and peroxymonosulfate (PMS) as the chemical oxidizers. The Ni2[email protected] foam anode showed a high oxidation activity for UOR with an onset potential of 0.30 V vs. Ag/AgCl and Tafel slope of 34.4 mV/dec. PMS with high theoretical potential improved the cell voltage to 1.43 V. A power density of DUFC up to 4.91 mW/cm2 was achieved using PMS at room temperature, which was approximately twice as high as using H2O2 (2.38 mW/cm2). NiII/NiIII was the redox active species on the Ni2P anode in the DUFC process, and NiII was electrochemically oxidized to NiIII, which reverted to NiII by urea reduction. When real human urine was used as the fuel, a power density of 4.46 mW/cm2 can be achieved at room temperature. This DUFC with high cell performance showed potential application in urea wastewater treatment. 相似文献
689.
上海市化石燃料排放二氧化碳贡献量的研究 总被引:16,自引:0,他引:16
采用ORNL提出的化石燃料燃烧排放二氯化碳的计算方法研究了上海市1994~2005年二氯化碳的排放量。得出上海化石燃料排放的二氯化碳将由1994年的3299.7万t增加到2005年的4493.44万t。同时得出煤炭、石油、天然气排放的二氯化碳比重将分别由1994年的84.03%下降到2005年的72.04%,1994年的15.97%上升到2005年的18.35%、2000年的0.38%上升到2005年的4.1%。 相似文献
690.
1 BackgroundAsurbanairpollutionbecomesmoreseriousinChina,emissionsfromvehiclesbecomemoreimportant.Fuelqualityisoneofthekeyfactorsaffectingvehicularemissions.Changesinthecompositionandpropertiesoffuelcanaffectvehicleemissionssignificantly.Whiletheinstal… 相似文献