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71.
讨论了氯化钡废液联产氢氧化钙及高纯氯化钡的方法和主要影响因素。通过复盐共沉淀、热滤、结晶、精制纯化等工序,用氯化钡的蒸发残液制得了工业级的氢氧化钙和高纯度氯化钡,其纯度分别达95%和99.92%以上。采用有机溶剂析出法精制氯化钡,无需重结晶工序,是对传统工艺的一种改进。  相似文献   
72.
• Punishments increase the participation probability of collectors and recyclers. • Policy-sponsored incentives make collectors and recyclers to participate earlier. • Recyclers are more sensitive to government punishments than collectors. Because governments have introduced policies involving incentives and penalties to promote the recycling of plastic waste, it is important to understand the impact of such incentives and penalties on the willingness of stakeholders to participate. In this study, government is included as a player, alongside waste collectors and recyclers, in a tripartite evolutionary game model of plastic waste recycling. The study explores the evolutionary equilibrium and performs a simulation analysis to elucidate the effect of government incentives and penalties on the willingness of other players to participate in recycling. Three conclusions are drawn from this research. First, an increase in incentives or in penalties increases the probability that collectors and recyclers will participate in the recycling process. Second, policy support incentives encourage collectors and recyclers to participate in plastic waste recycling earlier than subsidy incentives do. Finally, recyclers are more sensitive than collectors to government-imposed penalties.  相似文献   
73.
本文介绍了抗静电织物的分类和发展状况,对抗静电机理进行剖析。阐述了织物抗静电性能的测试方法,继而对其在生活中的应用进行探讨,最后对其发展的前景进行展望。  相似文献   
74.
黄河兰州段悬移质泥沙对氨氮的吸附特性   总被引:1,自引:0,他引:1  
实验研究了黄河兰州段不同粒径的悬浮泥沙对氨氮的吸附行为,拟阐释黄河兰州段水质自净的机制。通过分析探讨了含沙量、氨氮初始浓度、泥沙粒径和化学成分对氨氮吸附过程的影响。结果表明,准二级动力学方程和Langmuir模型能够较好地描述黄河兰州段不同粒径泥沙的吸附动力学和等温吸附过程(R20.9);含沙量对泥沙吸附氨氮作用具有显著影响,且氨氮吸附量和平衡时间与含沙量呈明显负相关性;氨氮初始浓度与氨氮吸附量及平衡时间呈正相关性;同时,泥沙颗粒越细,吸附氨氮的能力越强,吸附容量越大,反应的自发程度越高。此外,泥沙有机质、Fe2O3、Al2O3和MgO的含量随粒径减小而增大,它们对单位质量泥沙最大吸附量(Sm)具有正效应。泥沙的吸附在黄河兰州段水质自净过程中起着一定的促进作用。  相似文献   
75.
为了弄清空速与二氧化碳含量对氧化铁脱硫剂硫容确定的影响,分别在实验气源为纯硫化氢,空速为40、80、120和160 h-1以及实验气源为二氧化碳含量分别在0%、20%、40%和80%,其余为硫化氢,空速为80 h-1条件下,对T502(粗脱硫剂)和HXT-2(精脱硫剂)2种氧化铁脱硫剂进行了不同测试条件对氧化铁硫容确定影响的研究。研究结果表明,T502和HXT-2氧化铁脱硫剂硫容测试结果随着空速和二氧化碳含量增加而减少,结果显示了在空速较低条件下(120h-1),二氧化碳含量在40%以下时对氧化铁脱硫剂硫容测试结果影响不大,但二氧化碳含量在40%以上时,对氧化铁脱硫剂硫容测试结果影响显著。  相似文献   
76.
实验以吉林石化污水处理厂初沉池出水为原水在SBR中培养好氧颗粒污泥。实验初期,依次以比例为40%、60%的含石化废水的培养液进行培养,于第15天SBR中出现颗粒污泥,此后直接采用石化废水培养,同时逐步缩短沉降时间,第27天起反应器出水稳定,COD去除率达到89%,TN、NH3-N和TP去除率分别达到56%、86%和90%。采用此方法培养的颗粒污泥平均粒径约为1.3 mm,外表棕黄色,颗粒表面粗糙,在扫描电子显微镜(SEM)下观察到好氧颗粒污泥主要由杆状菌和丝状菌组成,颗粒内部存在若干孔隙。研究结果表明,在SBR中通过逐步增加石化废水进水比例,缩短沉降时间可以快速培养出好氧颗粒污泥,好氧颗粒污泥处理石化废水效果良好。  相似文献   
77.
In this study, the sediment profiles of total organic carbon, total nitrogen, C/N ratios, total phosphorus, N/P ratios, C/P ratios, particle sizes, and stable carbon and nitrogen isotopes (δ(13)C and δ(15)N) were used to investigate natural and anthropogenic impacts on Lake Chaohu over the past 100 years. Before 1960, Lake Chaohu experienced low productivity and a relatively steady and low nutrient input. The increasing concentration and fluxes of total organic carbon, total nitrogen, total phosphorus, together with changes in the δ(13)C and δ(15)N of organic material in the sediment cores, suggested that the anthropogenic effects on trophic status first started because of an increase in nutrient input caused by a population increase in the drainage area. With the construction of the Chaohu Dam, an increase in the utilization of fertilizer and the population growth which occurred since 1960, stable depositional conditions and increasing nutrient input resulted in a dominantly algae-derived organic matter source and high productivity. Nutrient input increased most significantly around 1980 following the rapidly growing population, with concomitant urbanization, industrial and agricultural development. This study also revealed that the concentration and distribution of nutrients varied between different areas of sediment within Lake Chaohu because of the influence of different drainage basins and pollution sources.  相似文献   
78.
Many studies indicate that lead (Pb) and cadmium (Cd) exposure may alter bone development through both direct and indirect mechanisms, increasing the risk of osteoporosis later in life. The aim of this study was to investigate the association between Pb and Cd exposure, physical growth, and bone and calcium metabolism in children of an electronic waste (e-waste) processing area. We recruited 246 children (3–8 years) in a kindergarten located in Guiyu, China. Blood lead levels (BLLs) and blood cadmium levels (BCLs) of recruited children were measured as biomarkers for exposure. Serum calcium, osteocalcin, bone alkaline phosphatase, and urinary deoxypyridinoline were used as biomarkers for bone and calcium metabolism. Physical indexes such as height, weight, and head and chest circumference were also measured. The mean values of BLLs and BCLs obtained were 7.30 μg/dL and 0.69 μg/L, respectively. The average of BCLs increased with age. In multiple linear regression analysis, BLLs were negatively correlated with both height and weight, and positively correlated with bone resorption biomarkers. Neither bone nor calcium metabolic biomarkers showed significant correlation with cadmium. Childhood lead exposure affected both physical development and increased bone resorption of children in Guiyu. Primitive e-waste recycling may threaten the health of children with elevated BLL which may eventually cause adult osteoporosis.  相似文献   
79.
以MEA为主体,DETA为添加剂,考察1h内,在温度298~338K,压力300~700kPa,混合胺溶液初始浓度(质量分数)4%~20%范围内,MEA+DETA不同配比的混合吸收剂吸收CO2的特性。获得MEA+DETA混合胺吸收CO2的最佳吸收条件为:308K、500kPa、总胺质量浓度为20%,MEA与DETA的配比为8:2。  相似文献   
80.
通过在高温好氧堆肥中分别添加VT菌剂和有机物料腐熟剂,研究接种3%o的VT菌剂和有机物料腐熟剂促进堆肥的作用效果。结果表明,接种VT菌剂的处理与空白和接种有机物料腐熟剂的处理相比,堆肥初期升温更快;高温期更长;堆肥结束时,C/N降低的多,NO3-N增加的多,NH4-N挥发的少,接种VT菌剂和VT有机物料腐熟剂都可促进有机质的充分降解,缩短堆肥时间,加快堆肥腐熟,提高堆肥肥力。  相似文献   
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