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Understanding the runoff characteristics and interaction processes between the mainstream and its tributaries are an essential issue in watershed and water management. In this paper, hydrogen (δD) and oxygen (δ 18 O) isotope techniques were used in the mainstream and Zhuyi Bay (ZYB) of the Three Gorges Reservoir (TGR) during the wet and dry seasons in 2015. It revealed that (1) Precipitation was the main source of stream flow compared to the TGR water line with meteoric water line of the Yangtse River basin; (2) The δD and δ 18 O values exhibited a 'toward lighter-heavier' trend along mainstream due to the continuous evaporation effect in the runoff direction, and the fluctuations reflected incoming water from the nearest tributaries. The general trend of d-excess increased with increasing distance from the Three Gorges Dam, which indicated that kinetic fractionation was an important process affecting the isotopic composition. The enrichment effect of isotopes was found in the downstream of TGR; (3) Water mass from the TGR mainstream flowed backward to the confluence zone of ZYB via the middle and bottom layers in the dry season, whereas in the wet season, water reversed through the upper-middle layers due to thermal density flows. This study described and demonstrated that the water cycle of TGR was driven by natural environmental variability and operational system, which will provide valuable information for the water resource management and for controlling the algal blooms in the future.

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In order to improve the decolorization of dyeing wastewater, reduce the resources and energy consumption of the wastewater treatment process, Activated carbon from bean dregs (ACBD) was prepared the first time. The decolorizing effects of Methylene Blue on the activated carbon-microwave degradation were discussed. The decolorizing rate of dye-wastewaters respect on adsorbent time(t), adsorbent dosage(m) and pH value were investigated. And the conventional treatment results were compared. The results showed that microwave radiation could accelerate the adsorption of dye on carbon. Improve the decolorization rate and reduce the bleaching time. The decolorization rate reach to 98% after 10 seconds with 1.67g/L ACBD at pH=5.66 when 60mL for the 250mg/L dye wastewater. Compared with usual adsorption, conventional methods take 90min to reach the bleaching effect of microwave radiation just 10s under differently the quantity of ACBD. The decolorization time reduces greatly by microwave degradation.

The adsorption of CO2 on a non-woven fabric with activated carbon before and after dipping treatment has been studied. It has been found that dipping treatment with Na2CO3 and KOH can improve the adsorption of CO2 on the non-woven fabric. KOH is a better dipping agent than Na2CO3. High temperature is beneficial to the adsorption of CO2 on the fabric dipped with KOH. With increasing relative humidity, the adsorption efficiency is decreased for both original fabric and that dipped with KOH. Increasing adsorption layer number can improve adsorption efficiency. However, when the number of adsorption layers exceeds 3 the increased amplitude of adsorption efficiency is obviously reduced, while the pressure loss of the system is remarkably increased.