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21.
建立了镦挤变形的模式,采用上限元技术模拟了镦挤变形的全过程,并讨论了摩擦和模口尺寸等参数对变形力和金属流动的影响。  相似文献   
22.
一体式A/O摇动床工艺处理石化废水   总被引:1,自引:0,他引:1  
针对国内许多石油化工废水处理工艺中氨氮降解效果差的问题,采用新型Biofringe填料设计一体式A/O摇动床工艺,对反应器的操作参数和去除效果进行了试验.结果表明:水力停留时间对氨氮去除负荷的影响较大,在水力停留时间为20.8 h,回流比为3.5时,COD的去除率可以达到90%以上,NH3-N的去除率可以达到95%以上,TN的去除率可以达到70%以上.通过一年多的小试,反应器具有动力消耗低,抗冲击能力强,操作稳定等特点,为进一步在石油化工废水处理中的应用提供了实验依据.  相似文献   
23.
Nowa days, ecological and cultural tourism, especially those ancient villages and towns in China, have attracted an increasing number of tourists because of their unique cultural features. However, rapid development of tourism brings economic benefits, but results in a series of problems that threaten further tourism development and protection of ancient towns, such as over-commercialization and tourism urbanization. Taking Longmen ancient town as an example, this paper presented a sustainable way of preserving and developing resources of ancient villages and towns. First, identify cultural features and the extent of ancient villages and towns, and find the approach through which a cultural landscape zoning can be applied. Second, define a cooperative function area to release the pressure on core areas and protect their authentic cultures by extending tourism space. Third, balance tourism development with traditional industries to enhance the sustainability of community economies.  相似文献   
24.
In this research, a two-step process consisting of vacuum pyrolysis and vacuum centrifugal separation was employed to treat waste printed circuit boards (WPCBs). Firstly, WPCBs were pyrolysed under vacuum condition at 600 °C for 30 min in a lab-scale reactor. Then, the obtained pyrolysis residue was heated under vacuum until the solder was melted, and then the molten solder was separated from the pyrolysis residue by the centrifugal force. The results of vacuum pyrolysis showed that the type-A of WPCBs (the base plates of which was made from cellulose paper reinforced phenolic resin) pyrolysed to form an average of 67.97 wt.% residue, 27.73 wt.% oil, and 4.30 wt.% gas; and pyrolysis of the type-B of WPCBs (the base plates of which was made from glass fiber reinforced epoxy resin) led to an average mass balance of 72.20 wt.% residue, 21.45 wt.% oil, and 6.35 wt.% gas. The results of vacuum centrifugal separation showed that the separation of solder was complete when the pyrolysis residue was heated at 400 °C, and the rotating drum was rotated at 1200 rpm for 10 min. The pyrolysis oil and gas can be used as fuel or chemical feedstock after treatment. The pyrolysis residue after solder separation contained various metals, glass fibers and other inorganic materials, which could be recycled for further processing. The recovered solder can be reused directly and it can also be a good resource of lead and tin for refining.  相似文献   
25.
本文根据部队官兵需要,明确了重新研制07A系列军用制式皮鞋的重要意义,并逐一说明了07A系列常服皮鞋、礼服皮鞋的产品特点。  相似文献   
26.
三峡库区小城镇污水处理工艺现状调查   总被引:2,自引:0,他引:2  
通过对三峡库区重庆段小城镇10家污水处理厂处理工艺和运行效果的调查,针对库区情况,分析比较了所调研污水处理厂使用工艺的处理效果、运行稳定性、自控要求、二次污染(剩余污泥产量)等技术指标以及建设投资、占地面积、处理成本、能耗等经济指标。对三峡库区小城镇排水工程规划建设,污水处理工艺的选择与开发,污水处理方案的优化提出明确的技术经济指标和建议。  相似文献   
27.
An experimental system including pressure transducer, electric spark ignition device, data acquisition and control unit was set up to investigate methane–air explosions in a horizontal pipe closed at both ends with or without the presence of obstacles and deposited coal dust. The experimental results show that explosion characteristics depended on the methane content, on the layout of obstacles, and on the deposited coal dust. Pressure fluctuation with a frequency of 150 Hz appeared in its crest when the methane content was close to the stoichiometric ratio (9.5% methane percentage by volume). The pressure rise rate increased locally when a single obstacle was mounted in the pipe, but it had little effect on the pressure peak. Repeated obstacles mounted in the pipe caused the pressure to rise sharply, and the mean maximum explosion overpressure increased with the increase of the obstacle’s number. The amplitude of pressure fluctuation was reduced when deposited coal dust was paved in the bottom of the pipe. However, when repeated obstacles were arranged inside, the maximum overpressures were higher with coal dust deposited than pure gas explosions.  相似文献   
28.
从取自染料生产废水处理厂的厌氧污泥中驯化、培养出混合高效脱色菌,研究其对水溶性染料废水的脱色工艺条件及脱色广谱性.实验结果表明:对活性红X-3B染料废水,当废水pH为7.5、反应温度为35℃、不另外投加N和P时,处理12h以上,脱色效果良好;不同结构水溶性染料的废水的脱色效果不同;在最佳脱色工艺条件下,选育的混合脱色菌对多种不同种类的水溶性染料废水均具有较高的脱色率.  相似文献   
29.
在调查研究了三峡库区重庆段小城镇污水处理现状的基础上,根据库区水质特征、水环境保护的特殊要求和库区地理环境与经济条件特点,对适用污水处理工艺和技术进行比选,认为利用地形高差,采用跌水曝气式生物滤塔+氧化沟处理方法是适用于库区小城镇的污水处理工艺与技术.  相似文献   
30.
废旧冰箱无害化再生处理的关键技术   总被引:1,自引:1,他引:0  
分析了废旧冰箱的结构特点和材料组成,介绍了其整体回收处理工艺及特殊部件再生处理的关键性技术。  相似文献   
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