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711.
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This paper presents a study on the resource and environmental profile of leather for communicating to the consumers about the environmental burdens of leather products. The results indicate that significant environmental impacts were caused during the tanning and finishing of leather as well as the electricity production and transportation required in the life cycle. The use of fossil fuels in the production of energy has greater impact with increased emissions leading to about 15190 kg CO2 equivalent of global warming and about 73 kg SO2 equivalent of acidification while producing 100 m2 of leather for shoe uppers. Further resource use of 174 kg of coal, 6.5 kg of fuel oil, 17.4 m3 of water and 348 kg of chemicals of which about 204 kg are hazardous are consumed, and wastewater of about 17 m3, BOD of 55 kg, COD of about 146 kg, TDS of 732 kg and solid waste of about 1445 kg are generated during the life cycle for the production of 100 m2 of leather. The total solid waste generated is 1317 kg, out of which about 80% is biodegradable contributed by slaughtering, tanning and finishing stage, 14% is non-biodegradable contributed by tanning, finishing and electricity production stages and 6% is hazardous mainly from tanning and finishing stage of leather. 相似文献
713.
Joseph P. Dudley § Joshua R. Ginsberg † rew J. Plumptre † John A. Hart † Liliana C. Campos‡ 《Conservation biology》2002,16(2):319-329
714.
John M. Pierrard Ronald D. Snee Joseph Zelson 《Journal of the Air & Waste Management Association (1995)》2013,63(9):841-848
Urban ambient air quality trend analysis was evaluated as an alternative to rollback analysis to estimate vehicle emission standards needed to achieve national ambient air quality standards. Examination of the trends of monthly maximum 8 hour average carbon monoxide concentrations, central business district traffic activity, and emission rates from vehicles on the road suggests that the automotive exhaust emission standard for carbon monoxide derived in response to the requirements of the Clean Air Act Amendments of 1970 may be ten times too severe. The excessive stringency of the vehicle emission standard for carbon monoxide was confirmed by two different analyses of the correlation between annual mean carbon monoxide concentration and frequency of occurrence of carbon monoxide concentrations above the level of the 8-hour standard. One correlation analysis using all available CAMP data involved an empirical approach and the other assumed that carbon monoxide concentrations are described by the lognormal distribution. Based on the analysis of CAMP air quality data, a vehicle carbon monoxide emission standard of approximately 29 grams per mile appears adequate to meet the ambient air quality standard. The large difference between the results of this analysis and the 1976 Federal vehicle carbon monoxide emission standard indicates the advisability of applying this methodology to verification of the standards for hydrocarbons and oxides of nitrogen. 相似文献
715.
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717.
Joseph M. Colucci Charles R. Begeman 《Journal of the Air & Waste Management Association (1995)》2013,63(3):113-122
The General Motors Research Laboratories and the Sloan-Kettering Institue for Cancer Research are collaborating to determine the contribution by automotive vehicles to the polynuclear aromatic hydrocarbons in city air. Sampling of particulate matter at the rate of 140 M3/min (5000 cfm) was carried out at two heavily-trafficked sites in Detroit and one suburban site in Warren, Michigan. Carbon monoxide was determined continuously, and particulate matter was analyzed for “tar,” polynuclear aromatic hydrocarbons, lead, vanadium, and sulfates. Polynuclear aromatic hydrocarbons in automobile exhaust gas are assumed to be dispersed in air along with carbon monoxide or lead from automobiles. It is further assumed that automobiles are the sole source of carbon monoxide and lead in the atmosphere. Concentrations of carbon monoxide and lead in exhaust gas and in the air are utilized to estimate the percentage of polynuclear aromatic hydrocarbons in the air attributable to automobiles. The mean automobile contributions to benzo(a)pyrene in the air, based on lead concentrations, were 18% at a Freeway Interchange, 5% in a downtown commercial area, and 42% in suburban Warren. The average concentrations of benzo(a)pyrene at the sites were 6 μg/103 M3, 7 μg/103 M3 and 1 μg/103 M3, respectively. Mean contributions based on carbon monoxide concentrations were approximately twice the levels based on lead concentrations. Benzo(a)pyrene and benz(a)anthracene in air were not statistically related to carbon monoxide or lead in air, but were higher in winter than in summer, probably because of the higher levels of these materials emitted in space heating combustion in winter. 相似文献
718.
Joseph Goldfield Kumud Gandhi 《Journal of the Air & Waste Management Association (1995)》2013,63(1):95-97
Abstract A method using direct flame ionization detector (FID) measurement was developed to study total volatile organic compound (VOC) emissions during thermal degradation of polymers. This method was used to estimate organic emissions from different polymers, such as low-density polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and commingled postconsumer streams, such as recycled carpet residue and auto shredder residue (ASR). The effects of process parameters, such as temperature, heating rate, and residence time, were also studied. Significant VOC emissions were observed at normal processing temperatures, particularly from recycled polymers. Each polymer showed a distinct evolution pattern during its thermal degradation. The kinetics of VOC emissions were also studied using a nonisothermal technique. The kinetic parameters were in agreement with data from the literature. 相似文献
719.
Simulating the effects of urbanization,afforestation and cropland abandonment on a regional carbon balance: a case study for Central Germany 总被引:1,自引:0,他引:1
The newly developed model system HILLS is used to simulate recent (1990–2000) and future (up to 2020) changes in land use
and carbon sequestration over Central Germany. HILLS is unique as that it integrates the spatially explicit land-use-change
model LUC-Hesse with the dynamic ecosystem model Century under a GIS platform. With this new tool, the concurrent effects
of urbanization, afforestation and cropland abandonment on regional carbon sequestration are analyzed for an exemplary “Business
as Usual” scenario. During the simulation period, afforestation was estimated to sequester 880 Gg C and cropland abandonment
783 Gg C. Urbanization was estimated to release 336 Gg C formerly stored in soil organic matter and thereby offsets about
20% of the C sequestered by cropland abandonment and afforestation. The case study shows that urbanization can partly counteract
the benefits of carbon sequestration resulting from other land-use changes and should be investigated in other carbon balances. 相似文献
720.