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41.
Abstract

Although the fugitive dust associated with construction mud/dirt carryout can represent a substantial portion of the particulate matter (PM) emissions inventory in non-attainment areas, it has not been well characterized by direct sampling methods. In this paper, a research program is described that directly determined both PM10 and PM2.5 (particles ≤10 and 2.5 μm in classical aerodynamic diameter, respectively) emission factors for mud/dirt carryout from a major construction project located in metropolitan Kansas City, MO. The program also assessed the contribution of automotive emissions to the total PM2.5 burden and determined the baseline emissions from the test road. As part of the study, both time-integrated and continuous exposure-profiling methods were used to assess the PM emissions, including particle size and elemental composition. This research resulted in overall PM10 and PM2.5 emission factors of 6 and 0.2 g/vehicle, respectively. Although PM10 is within the range of prior U.S. Environmental Protection Agency (EPA) guidance, the PM2.5 emission factor is far lower than previous estimates published by EPA. In addition, based on both the particle size and chemical data obtained in the study, a major portion of the PM2.5 emissions appears to be attributable to automotive exhaust from light-duty, gasoline-powered vehicles and not to the fugitive dust associated with re-entrained mud/dirt carryout.  相似文献   
42.
Antioxidant capacity, total phenol and mineral contents of aerial parts of sage belonging to some Salvia species were established. The lowest and highest antioxidant values of Salvia dichroantha Stapf and Salvia heldreichiana Boiss. ex Benth. extracts were found as 73.855 and 80.207 mg GAE/g, respectively. While the highest total phenol was established in Salvia tomentosa Mil. (13.316 mg GAE/100 ml), the lowest level was found in Salvia halophila Hedge (6.168 mg GAE/100 ml). While K contents of plants changed between 14,518 and 24,171 mg/kg, Ca contents ranged between 12,402 and 18,553 mg/kg. P and Mg contents were found low compared with K and P values of plants. Mg content was changed between 2,118 and 2,914 mg/kg; the mean was calculated as 2,496 mg/kg. P contents of plants were determined between 1,385 to 1,910 mg/kg. As a microelement, Fe was found at the highest level. Fe contents of plants were found between 179 and 782 mg/kg.  相似文献   
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44.

Introduction  

Balya and its associated villages which is a town of the Balikesir region of Turkey have very rich zinc, lead, and manganese mines. These mines have been operating since the thirteenth century and now there is heavy metal contamination in both the soil and natural waters in these areas.  相似文献   
45.
Summary A postal survey of 992 secondary students in Hong Kong using the Weigel and Weigel environmental concern scale was conducted to investigate their environmental attitudes which were reflected in a readiness to engage in various pro-environmental behaviours including paper recycling at school and at home and the use of less tissues and plastic bags. The results indicated that students' expressed great concern about the environment and exhibited a strong willingness to participate in pro-environmental behaviour. However, students' overoptimism towards technological development and the perceived importance of the benefits of modern consumer goods were two major factors that contradicted their concern for environment. The Pearson correlation coefficient between environmental concern and comprehensive behavioural intention was strong and positive (0.52). Television and school were cited as major sources of environmental information. Mass media were more important than personal media in the dissemination of environmental information. Female students, older students and students living in private housing held more positive environmental attitudes and were more willing to engage in pro-environmental behaviour. Factor analysis indicated that the environmental concern scale was composed of two factors, personal sacrifice and optimism/issue.Ms Kara K.W. Chan is currently an assistant professor in the Department of Communication Studies, School of Communication, Hong Kong Baptist University. She has previously worked in the advertising and public relations profession and as a statistician for the Hong Kong Government. She is actively involved in research on Hong Kong and China's mass communication and advertising industry, consumer behaviour and the promotion of pro-environmental behaviour.  相似文献   
46.
Data on the short-term effects of fumigation with hydrogen fluoride (HF) on the response behavior of the Nicotiana tabacum L. cv. St. Karabalar 6265 are being presented. Growth rate, fluoride accumulation in leaves and soils, and degradation in chlorophyll and nicotine contents of the plant species against the variations in two experimental factors, namely the exposure concentration and exposure time parameters, were investigated. Resulting data reveals that the variety selected for this study is not so tolerant to fluoride as generally reported in the literature, if only the individual effects of the pollutant is considered.  相似文献   
47.
Past global efforts at dealing with the problem of global warming concentrated on mitigation, with the aim of reducing and possibly stabilizing greenhouse gas (GHG) concentrations in the atmosphere. With the slow progress in achieving this, adaptation was viewed as a viable option to reduce the vulnerability to the anticipated negative impacts of global warming. It is increasingly realized that mitigation and adaptation should not be pursued independent of each other but as complements. This has resulted in the recent calls for the integration of adaptation into mitigation strategies. However, integrating mitigation and adaptation into climate change concerns is not a completely new idea in the African Sahel. The region is characterized by severe and frequent droughts with records dating back into centuries. The local populations in this region, through their indigenous knowledge systems, have developed and implemented extensive mitigation and adaptation strategies that have enabled them reduce their vulnerability to past climate variability and change, which exceed those predicted by models of future climate change. However, this knowledge is rarely taken into consideration in the design and implementation of modern mitigation and adaptation strategies. This paper highlights some indigenous mitigation and adaptation strategies that have been practiced in the Sahel, and the benefits of integrating indigenous knowledge into formal climate change mitigation and adaptation strategies. Incorporating indigenous knowledge can add value to the development of sustainable climate change mitigation and adaptation strategies that are rich in local content, and planned in conjunction with local people.  相似文献   
48.
The present study includes synthesis of two γ-Al2O3 samples from waste aluminum cans using a simple precipitation method. Precipitation was carried out using two different precipitating agents (i.e. NaOH and NH4OH). The two prepared alumina samples were characterized by means of X-ray diffraction (XRD) and N2 adsorption–desorption techniques. Surface acidity of γ-Al2O3 samples was measured by adsorption of two different probe molecules (i.e. pyridine and dimethyl pyridine) followed by desorption measurements using thermogravimetry (TG) and differential scanning calorimetry (DSC) techniques. Catalytic activity of the two prepared alumina samples towards the dehydration of methanol (to dimethyl ether) was studied in a fixed bed reactor at 300 °C. For comparison reasons, commercial γ-Al2O3 sample was, also, tested for the same catalytic reaction under the same conditions. Results showed that the alumina sample prepared using NaOH as a precipitating agent exhibited a better catalytic activity and stability compared with that prepared using NH4OH and showed a similar activity as the commercial γ-Al2O3 sample.  相似文献   
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50.
Persistence of carbaryl in canal water   总被引:2,自引:0,他引:2  
The presence of the insecticide carbaryl (Sevin) and its decomposition product 1-napthol was confirmed in irrigation and drainage canal water. However, their residues disappeared from the water 6 days after application.  相似文献   
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