Field measurements were conducted in four representative rural areas across China to determine carbonaceous aerosol emissions from combustion of household biofuel. Results showed that the size distribution of both black carbon (BC) and organic carbon (OC) peaked at 0.26-0.38 microm. OC accounted for a significant fraction of fine particles from wheat residue combustion across all size categories, whereas both BC and OC accounted for a significant fraction of fine particles from fuel wood combustion across all size categories. The emission factors for crop wastes are 0.43 +/- 0.32 and 1.93 +/- 1.00 g/kg for BC and OC, respectively. The emission factors for woody fuel were 1.49 +/- 0.69 g/kg and 1.13 +/- 0.40 g/kg for BC and OC, respectively. Woody fuel BC-to-PM2.5 ratios were significantly higher than the ratios from crop waste, ranging from 36.40 to 71.18%, relative to crop waste BC-to-PM2.5 ratios which ranged from 1.70 to 33.52%. Woody fuel also had high BC-to-OC ratios, ranging from 0.95 to 2.51. Woody fuel combustion accounts for approximately two-thirds of China's estimated 430 Gg of BC emissions and crop waste combustion accounts for approximately 80% of China's 922 Gg of OC emissions from household biofuel combustion in 2005.

The purpose of this investigation is to evaluate the current status and identify the problems of municipal solid waste (MSW) management in China in order to determine appropriate remedial strategies. This is the first of two papers, discussing primarily the general characteristics of MSW and its management in China. The second paper focuses on specific remedial strategies. MSW generation in China has increased rapidly in the past 20 years from 31.3 million tons in 1980 to 113.0 million tons in 1998. The annual rate of increase is 3-10%. The average generation per capita is 1.0 kg/day (0.38 t/year). Nearly one-half of the waste generated is dumped in the suburbs, where the accumulated quantity has reached 6 billion tons, which has caused heavy environmental pollution. This paper provides information on MSW management in China, such as MSW generation and its physical, chemical, and biological properties. Low calorific value and high moisture content characterize China's municipal waste. Other issues related to MSW management in China are also discussed, including the factors that influence MSW generation quantity and IMPLICATIONS With the rapid economic development in China, solid waste pollution is becoming more serious and has raised vast public concern. This paper discusses primarily the characteristics of MSW and the waste management systems in China. The Act of Prevention and Control of Solid Waste Pollution to the Environment, People's Republic of China, which was enacted in 1995, instituted that source minimization, recycling, and treatment/disposal in an environmentally sound manner is a primary principle of MSW management in China. To implement the law, the management systems require significant improvement. Before anything can be done, we must understand clearly what the current situation is in MSW management and what sorts of problems we have to face so that we can decide what to do and how to do it. Results of this investigation provide background information for the improvement of MSW management in China.quality, MSW collection, transfer and transport, treatment and disposal, material recovery, legislation, enforcement, and administration.

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In this study, the mass transfer and reaction kinetics of soybean oil epoxidation using concentrated hydrogen peroxide in a formic acidautocatalyzed reaction system were studied in detail. Studying the mass transfer of formic acid showed that the influence of reactant diffusion near the interface is eliminated when the stirring rate is > 120 rpm in a double-stirred cell, and the mass transfer rate decreases greatly with the conversion of double bonds and a decrease of reaction temperature. A temperature increase has little impact on the equilibrium of formic acid in the oil/water system, while an increase of epoxidized soybean oil significantly increases the value of the partition coefficient of formic acid. Another important aspect in the kinetic study is the decomposition of performic acid, which can cause the reduction of H 2 O 2 and formic acid during the reaction. Finally, a biphasic model, which considers all reactions in oil and aqueous phases, the equilibrium and mass transfer of reagents and products between the phases, and the evolution of proton concentrations with time, was developed to describe the epoxidation process.

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