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791.
The solubilization of blood meal by means of the microwave-hydrogen peroxide enhanced advanced-oxidation process (MW/H(2)O(2)-AOP) was studied. It was found that over the treatment temperature range of 60 to 120 degrees C, solids particle reduction, ammonia and orthophosphate production could be achieved by this process. Large protein molecules were broken down into intermediate compounds with low molecule weights, ammonia and nitrate. Intermediate compounds, such as peptides and amino acids, can also be easily converted to nitrogenous nutrients for plant growth by bacteria. Soluble nitrogen content increased with an increase in microwave heating temperature when acid was added; significant amounts of ammonia were obtained at higher temperatures. Nitrate decreased in concentration with an increase of treatment temperature. Orthophosphate concentrations increased after the advanced-oxidation process (AOP) treatments, with and without acid addition; but were more pronounced with acid addition. Maximum solubility of chemical oxygen demand (COD) occurred at 80 degrees C. Without the addition of acid, soluble COD decreased due to protein denaturation and coagulation out of the solution.  相似文献   
792.
In order to investigate the effect of raw leachate on anaerobic digestion of food waste, co-digestions of food waste with raw leachate were carried out. A series of single-phase batch mesophilic (35 ± 1 °C) anaerobic digestions were performed at a food waste concentration of 41.8 g VS/L. The results showed that inhibition of biogas production by volatile fatty acids (VFA) occurred without raw leachate addition. A certain amount of raw leachate in the reactors effectively relieved acidic inhibition caused by VFA accumulation, and the system maintained stable with methane yield of 369–466 mL/g VS. Total ammonia nitrogen introduced into the digestion systems with initial 2000–3000 mgNH4–N/L not only replenished nitrogen for bacterial growth, but also formed a buffer system with VFA to maintain a delicate biochemical balance between the acidogenic and methanogenic microorganisms. UV spectroscopy and fluorescence excitation–emission matrix spectroscopy data showed that food waste was completely degraded.We concluded that using raw leachate for supplement water addition and pH modifier on anaerobic digestion of food waste was effective. An appropriate fraction of leachate could stimulate methanogenic activity and enhance biogas production.  相似文献   
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795.
Identification of representative sampling sites is a critical issue in establishing an effective water quality monitoring program. This is especially important at the urban-agriculture interface where water quality conditions can change rapidly over short distances. The objective of this research was to optimize the spatial allocation of discrete monitoring sites for synoptic water quality monitoring through analysis of continuous longitudinal monitoring data collected by attaching a water quality sonde and GPS to a boat. Sampling was conducted six times from March to October 2009 along a 6.5 km segment of the Wen-Rui Tang River in eastern China that represented an urban-agricultural interface. When travelling at a velocity of ~2.4 km h(-1), this resulted in water quality measurements at ~20 m interval. Ammonia nitrogen (NH(4)(+)-N), electrical conductivity (EC), dissolved oxygen (DO), and turbidity data were collected and analyzed using Cluster Analysis (CA) to identify optimal locations for establishment of long-term monitoring sites. The analysis identified two distinct water quality segments for NH(4)(+)-N and EC and three distinct segments for DO and turbidity. According to our research results, the current fixed-location sampling sites should be adjusted to more effectively capture the distinct differences in the spatial distribution of water quality conditions. In addition, this methodology identified river reaches that require more comprehensive study of the factors leading to the changes in water quality within the identified river segment. The study demonstrates that continuous longitudinal monitoring can be a highly effective method for optimizing monitoring site locations for water quality studies.  相似文献   
796.
登陆中国台风灾害损失预评估模型研究   总被引:1,自引:0,他引:1  
整理了2000-2008年登陆中国且灾情记录完整的34个台风案例,建立案例集;基于模糊数学法建立了台风灾害损失预评估模型。选择8项影响因子作为模型输入指标,利用层次分析法确定影响因子权重,计算案例集中每个台风的综合评价指数;通过对综合评价指数与受灾人口、农作物受灾面积及直接经济损失等典型灾情指标进行拟合;通过适当调整影响因子权重,拟合得出最优幂函数回归方程,从而实现对台风灾情的定量预评估。  相似文献   
797.
In the present work, characteristics of ethanol production from a single particle composing of pretreated rice straw, cellulase, and β-glucosidase were invesitgated by simultaneous saccharification and fermentation (SSF). The experiment experienced a start-up stage for S. cerevisiae biofilm formation, which was operated at an initial pH value of 4.8 for yeast solution, culture temperature of 30°C, flow rate of 0.8 mL/min for yeast solution, and stably operating stage for ethanol production at a culture temperature of 30°C. Investigations found that the maximal ethanol yield of 9.7 mg/g and the biofilm thickness of 0.37 mm were obtained at 30 mL/min of carrier gas flow rate. Also, the optimal interval time of water supplement was 4 h for SSF. The results show that the appropriate gas flow rate and the interval time of water supplement can keep the high activities of biofilm and enzymes during SSF and result in a high ethanol yield.  相似文献   
798.
利用氧化亚铁硫杆菌对煤中硫分的脱除作用,探讨了其对3种不同地域且不同矿物含量煤的脱硫作用。进行了未酸化与酸化处理煤样脱硫试验、温度影响试验、初始pH值影响试验。结果表明:未预处理条件下煤样I、n、Ⅲ的脱硫率分别为29.3%、3.9%、3.5%,酸处理后迭到39.8%、40.7%、4.2%。煤样Ⅰ、Ⅱ的最佳脱硫温度分别为35℃、30℃;温度30℃,初始pH为2.3时,煤样Ⅰ、Л的脱硫效果最好,分别为54%、67%;温度和pH的变化对煤样山的影响不大。30℃,初始pH为2.3时煤样Ⅰ、Ⅱ、Ⅲ的黄铁矿硫去除率分别为77%、83%、67%。  相似文献   
799.
污泥脱水是污水处理中的一个重要环节,影响脱泥用药(絮凝剂)的因素很多.水厂结合实验分析,发现污泥脱水中不同参数对耗药率影响较大.因此,采取了相应的工艺控制方法,在保障运行效率的基础上,有效降低污泥脱水运行成本.  相似文献   
800.
分析了国内外企业员工心理健康管理实施现状,阐述了石化企业引入员工心理健康管理模式的重要性和必要性,提出加强心理健康管理模式建设的建议.  相似文献   
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