Publications by authors named "Dong-jie Niu"

Molten salt has been regarded as a versatile and environmental-friendly method for the material preparation and waste destruction. In this work, molten FeCl3 was utilized for the generation of magnetic biochar (MBC) derived from simultaneous activation and magnetization of biomass. The sample characterization indicated that MBC had a rough surface with BET surface area of 404 m2/g and total pore volume of 0.

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Ecological planning is one of the most important tools in realizing city's sustainable development. The ecological planning in China was started in the 1980s, and on the basis of assimilating the existing theoretical and practical experiences from western countries, basically formed a theoretical system in accordance with the Chinese characteristics and acquired a series of practical results. This paper reviewed the research and development processes of China' s ecological planning.

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Ecological civilization is to normalize human development behaviors to harmonize the relationships between social and ecological development and eco-environment protection. In this paper, a comparative analysis was made on the ecological demonstration activities of ecological demonstration areas led by the Ministry of Environmental Protection, exemplar cities of national environmental protection, and ecological provinces, cities, and counties. It was considered that all the ecological demonstration activities had the problems of lacking pertinence of construction goals, disordered construction subjects, inefficient construction processes, and lacking continuous incentive mechanisms of assessment.

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About 20 million tonnes of sludge (with 80% moisture content) is discharged by the sewage treatment plants per year in China, which, if not treated properly, can be a significant source of greenhouse gases (GHGs) emissions. Anaerobic digestion is a conventional sewage sludge treatment method and will continue to be one of the main technologies in the following years. This research has taken into consideration GHGs emissions from typical processes of sludge thickening+anaerobic digestion+dewatering+residue land application in China.

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In this paper, we report the basic theory and method of single exposure interference lithography (IL) to fabricate two-dimensional (2D) superposed microstructures. Distribution of six-beam interference intensities with different azimuth angle is discussed, and 2D superposed microstructures with different periodic constants are obtained by computer simulations. The experiment results using CHP-C positive photoresist show a 2D superposed photonic crystal composed of a periodically repeated hexagonal pattern of hexagonal lattice cells, which is in close agreement with the computer simulation.

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Magnesium oxychloride cement (MOC) was used for the stability agent in the stabilization experiments of sewage sludge. It is found that MgCl2 in MOC is a kind of water-absorbent, water absorption of MgCl2 can be achieved at 1.55 mL/g (per 100 g sludge).

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A series of batch tests were conducted to investigate the effects of initial pH on bio-hydrogen production from acid pretreated municipal sludge. The pH of sludge was first adjusted to 2.0, 3.

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The individual effects and interactive effects of substrate concentration, ratio of inoculum to substrate, Ca(2+) concentration on the methane yield from the effluent of bio-hydrogen fermentation of food waste were investigated in this study. A central composite design (CCD) and response methodology (RSM) were employed in designing the experiments, in order to determine the optimum conditions for methane fermentation. The experiment results showed that the effects of substrate concentration, ratio of inoculum to substrate, Ca(2+) concentration were statistically significant at 5% level.

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Bioreactor landfill is an emerging landfilling method, which represents the newest developing aspect of Municipal Solid Wastes (MSW) treatment. On basis of analyzing the merits and defects of present bioreactor landfilling methods, the paper improves these methods and combines organically aeration and leachate recirculation into a new reactor (called reactor A), which is contrasted with bare aerobic landfill (called reactor B). During the course of experiment, NH3, CH4, CO2, pH, temperature and electric conductivity in the two bioreactors were controlled and detected, meanwhile, COD, Fe3+, NH4(+) in the leachate were detected and analyzed.

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