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41.
Characterizing effects of uncertainties in MSW composting process through a coupled fuzzy vertex and factorial-analysis approach 总被引:1,自引:0,他引:1
A coupled fuzzy vertex and factorial-analysis approach was developed in this study for systematically characterizing effects of uncertainties in a municipal solid waste composting process. A comprehensive composting process model was also embedded into the system framework and used to address substrate decomposition and biomass growth, as well as the interactions between moisture contents, temperatures, and oxygen concentrations. The applicability of the proposed method was verified through a custom-made pilot-scale composting system. Results from fuzzy simulation indicated that the fuzzy vertex method could effectively communicate implicit knowledge into dynamic simulations and thus provide valuable information for enhancing composting process control under uncertainty. The factorial analysis was effective in quantifying the proportion to which the uncertainty of each single or interactive effect of model parameters contributes to the overall uncertainty of the system outcomes. Thus, sensitive parameters that may lead to errors or unreasonable predictions can be determined. The proposed study system could not only be used in characterizing combined effects of uncertainties for composting processes, but was also applicable to many other environmental modelling systems. 相似文献
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水热变化对三峡水库消落带紫色土有机碳矿化的影响 总被引:1,自引:0,他引:1
通过野外采样和室内模拟培养试验,研究水热变化对三峡水库消落带紫色土有机碳(SOC)矿化的影响.试验共设3个培养温度(10、20和30℃)和4个水分梯度[40%田间持水量(WHC)、70%WHC、100%WHC和淹水].在66 d培养期内,SOC累积矿化量表现为100%WHC处理下的最大,但与淹水之间差异不显著(P0.05).10℃和20℃时,100%WHC和淹水下的SOC累积矿化量与70%WHC无明显差异,但要显著高于40%WHC,而30℃时100%WHC和淹水下的累积矿化量则要显著高于70%WHC和40%WHC(P0.05),这表明相较于70%WHC的水分处理,高水分(100%WHC和淹水)对SOC矿化无抑制效应甚至在高温(30℃)下有促进作用.在相同水分条件下,消落带紫色土SOC累积矿化量均随培养温度升高而增加.另外,方差分析可知,温度和水分均能显著影响消落带紫色土SOC的累积矿化量,且二者有明显交互效应(P0.05).双库一级矿化动力学模型拟合结果表明,水分和温度通过影响消落带紫色土易分解有机碳含量和难分解有机碳的矿化速率,致使各处理之间SOC累积矿化量存在差异,其中高温条件下水分影响最为突出.随着温度的升高,低水分(40%WHC)下消落带紫色土SOC矿化的温度敏感性显著下降,而在土壤含水量≥70%WHC下则无明显变化. 相似文献
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Comparison of quartz sand, anthracite, shale and biological ceramsite for adsorptive removal of phosphorus from aqueous solution 总被引:1,自引:0,他引:1
The choice of substrates with high phosphorus adsorption capacity is vital for sustainable phosphorus removal from waste water in constructed wetlands. In this study, four substrates were used: quartz sand, anthracite, shale and biological ceramsite. These substrate samples were characterized by X- ray diffractometry and scanning electron microscopy studies for their mineral components (chemical components) and surface characteristics. The dynamic experimental results revealed the following ranking order for total phosphorus (TP) removal efficiency: anthracite 〉 biological ceramsite 〉 shale 〉 quartz sand. The adsorptive removal capacities for TP using anthracite, biological ceramsite, shale and quartz sand were 85.87, 81.44, 59.65, and 55.98 mg/kg, respectively. Phosphorus desorption was also studied to analyze the substrates' adsorption efficiency in wastewater treatment as well as the substrates' ability to be reused for treatment. It was noted that the removal performance for the different forms of phosphorus was dependent on the nature of the substrate and the adsorption mechanism. A comparative analysis showed that the removal of particulate phosphorus was much easier using shale. Whereas anthracite had the highest soluble reactive phosphorus (SRP) adsorptive capacity, biological ceramsite had the highest dissolved organic phosphorus (DOP) removal capacity. Phosphorus removal by shale and biological ceramsite was mainly through chemical adsorption, precipitation or biological adsorption. On the other hand, phosphorus removal through physical adsorption (electrostatic attraction or ion exchange) was dominant in anthracite and quartz sand. 相似文献
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海南省旅游地评价及其开发研究 总被引:9,自引:2,他引:9
旅游地资源评价和开发研究,是进行旅游开发宏观决策,确定对应的旅游活动类型和接待规模,指导旅游市场开发与景区、景点设计时一项重要的基础研究工作。本文以海南省为例,对旅游地资源的评价制图和旅游开发用地预测方法,进行了有益的探讨。 相似文献
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海水鱼类网箱养殖的环境效应及多营养层次的综合养殖 总被引:4,自引:0,他引:4
海水鱼类网箱养殖是世界主要渔业国家(如挪威、日本等)广泛开展的一种高密度、集约化的养鱼方式,这种养殖方式在给广大从业者带来巨大经济、社会效益的同时,对环境也造成了不可忽视的负面影响。开展多营养层次的综合养殖(IMTA)是缓解这一环境压力的有效途径,鱼类养殖过程中释放出的二氧化碳、氮、磷等物质,由无机提取单元(大型藻类)来吸收,粪便和残饵等微小颗粒则成为有机提取单元(滤食性贝类)的饵料,较大的颗粒物质沉到海底后,可以为腐食性单元(海参等)提供食物,通过这种养殖模式,最大限度地实现系统内营养物质的高效利用,在减轻养殖对环境压力的同时,使系统具有较高的容纳量和食物产出能力。 相似文献
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通过对徐州市空气质量及其对应的气象因子进行统计分析,得出空气质量与相对湿度、风速,降水等气象因子的关系。分析特殊气象天气出现时空气中主要污染物PM10的变化规律.得到一些初步结果,为减轻和防止污染提供参考。 相似文献
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