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31.
This study presents the effects of citizen participation on integrated solid waste management. Porto Alegre was chosen as the area of study since its system is a good example for developing countries, based on the partnership between local government and the former scavengers' association that implements selective collection in the city. A life-cycle approach was used to estimate environmental loadings and economic costs based on solid waste generation, and a survey assessment tool was used to analyse social aspects. The results showed a decrease in environmental and economic impacts in the current situation, allowing Porto Alegre to have one of the most affordable integrated solid waste management systems in Brazil. The survey assessment pointed out that public campaign changed the perceptions and practices of most of Porto Alegre's citizens regarding solid waste management. On the other hand, it also pointed out that citizens need more education to increase their participation. Therefore, more research is needed to increase cooperation among all stakeholders, improve citizen participation, and consequently, further decrease the environmental impacts and economic costs. 相似文献
32.
We employed the contingent valuation method to estimate the willingness to pay of the respondents to improve the waste collection system in Dhaka city, Bangladesh. Our objective was to estimate how WTP differs between respondents who received or did not receive door to door waste collection. The methodology consisted of asking people directly about their willingness to pay an additional waste collection service charge to cover the costs of a new waste management project. The mean value of WTP for areas that received waste collection service areas was higher than for residents of areas that did not but the difference was not statistically significant. The aggregate value of WTP of the respondents in Dhaka city was 7.6 million Taka (USD0.1 million). 相似文献
33.
Yusuke Asakuma Yusuke Yamamura Kyuya Nakagawa Kouji Maeda Keisuke Fukui 《Journal of Polymers and the Environment》2011,19(1):209-216
The depolymerization reaction of polyethylene terephthalate (PET) was analyzed on the basis of both experimental data and
numerical data obtained from quantum chemistry calculations. Various alcohols were used as solvents in the search for the
reaction mechanism. The activation energy obtained from the optimized structures of the ground state and the transitional
state was compared with our experimental data. Based on these comparisons, it was found that the formation of rings from alkoxyl
groups and carbonyl carbon atoms at the transitional state is highly important when the ester bonds of PET are broken. Moreover,
the most appropriate alcohol was suggested for the depolymerization reaction. 相似文献
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35.
Shun'ichi Honda Naoyuki Miyata Keisuke Iwahori 《Journal of Material Cycles and Waste Management》2002,4(1):46-50
In our previous work, the primary sludge from wastewater treatment plants was shown to contain a considerable amount of cellulose
(about 20%, based on suspended solids) owing to the discharge of toilet paper. For the purpose of using the cellulose as a
biomass resource, this study examined a simple method for its recovery. When fibrous cellulose was suspended in 0.3% sulfuric
acid and autoclaved at 130°C for 60 min, 85%–88% of the initial solids remained without dissolving. Under these conditions,
an activated sludge sample not containing cellulose was strongly hydrolyzed and only 7% of the initial solids remained. The
prescribed amounts of cellulose added to the activated sludge sample were quantitatively recovered by the autoclaving treatment.
In the treatment of primary sludge containing >20% cellulose, residual solids with relatively high levels of cellulose (>69%)
could be obtained. The results indicate that the method proposed here could recover cellulose practically from waste sewage
sludge for biomass utilization.
Received: July 17, 2000 / Accepted: July 4, 2001 相似文献
36.
Ayako Yoshino Yasuhiro Sadanaga Keisuke Watanabe Shungo Kato Yuko Miyakawa Jun Matsumoto Yoshizumi Kajii 《Atmospheric environment (Oxford, England : 1994)》2006,40(40):7869-7881
Total OH reactivity was observed by use of the laser-induced pump and probe technique, and the urban air quality in Tokyo was diagnosed comprehensively. The concentrations of NOx, CO, O3, non-methane hydrocarbons (NMHCs) and oxygenated volatile organic compounds (OVOCs) were observed simultaneously. The observations were conducted in July and August 2003, and in January, February, May, and November 2004. Generally, the observed OH reactivity was higher than the calculated values derived using the observed concentrations of the trace species. The differences between the observed and calculated values in summer, spring, and autumn were approximately 30%. However, the difference in winter was smaller than those in the other seasons. In addition, while the differences observed in summer, spring, and autumn correlated with the total reactivity of the OVOCs (Σi kOVOCi[OVOCi](s−1), ki is rate constant of its compounds with OH), the correlations were not confirmed in the case of winter because atmospheric oxidation was less active and OVOCs levels were low in winter. These results suggest that the secondary products of the photochemical reactions in the atmosphere would be a missing sink for the OH loss process in the urban area. 相似文献
37.
Takahashi Akira Fukuda Keisuke Tsuji Kiyoshi Yoshikawa Kunio 《Water, Air, & Soil Pollution: Focus》2003,3(5-6):79-88
To evaluate the influence of anthropogenic emission of HCl on the air quality in the Kanto district of Japan, the atmospheric budgetof non-seasalt Cl (nssCl) was analyzed. The Kanto district, which consists of the Tokyo metropolis and the six surrounding prefectures, is the most densely populated region in Japan. The emission intensity of HCl is extremely high compared with those in other regions and most western countries. In this study, the annual wet and dry depositions of nssClwere estimated on a 0.25 × 0.25° grid over the Kanto district based on the concentration monitoring resultsand meteorological data. The budget analysis was conducted by comparing the estimated deposition with the emission of HCl. As a result, the annual total (wet + dry) deposition of nssCl was estimated to be 32 kt yr-1, which closely agreed with HCl emission (36 kt yr-1) from waste incineration in this area. The result suggested that the anthropogenic emission of HCl had a significant influence on the air quality and the deposition of acidity in this area. 相似文献
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Factors affecting waste generation: a study in a waste management program in Dhaka City, Bangladesh 总被引:1,自引:0,他引:1
Information on waste generation, socioeconomic characteristics, and willingness of the households to separate waste was obtained from interviews with 402 respondents in Dhaka city. Ordinary least square regression was used to determine the dominant factors that might influence the waste generation of the households. The results showed that the waste generation of the households in Dhaka city was significantly affected by household size, income, concern about the environment, and willingness to separate the waste. These factors are necessary to effectively improve waste management, growth and performance, as well as to reduce the environmental degradation of the household waste. 相似文献
40.
Shibata Hideaki Galloway James N. Leach Allison M. Cattaneo Lia R. Cattell Noll Laura Erisman Jan Willem Gu Baojing Liang Xia Hayashi Kentaro Ma Lin Dalgaard Tommy Graversgaard Morten Chen Deli Nansai Keisuke Shindo Junko Matsubae Kazuyo Oita Azusa Su Ming-Chien Mishima Shin-Ichiro Bleeker Albert 《Ambio》2017,46(2):129-142
Ambio - Nitrogen (N) management presents a sustainability dilemma: N is strongly linked to energy and food production, but excess reactive N causes environmental pollution. The N footprint is an... 相似文献