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排序方式: 共有521条查询结果,搜索用时 46 毫秒
1.
《International Journal of Hydrogen Energy》2020,45(17):10334-10341
Synergistic effect of sodium borohydride (NaBH4) mixed with waste aluminum in hydrolytic system were investigated to improve the hydrogen generation (HG) efficiency. The alkaline aqueous originated from NaBH4 hydrolysis impels the passive aluminum hydroxide film of Al surface to be dissolved, thus, mutual effect of HG amount increasing by 88% and 50% for Al powder and waste Al can, respectively. To add acid catalyst in the mutual mixture system prompts to significantly accelerate HG rate from 100 ml/min˙g to 400 ml/min˙g but raising temperature is not obviously found. It is speculated that exothermic effect dominates the NaBH4 hydrolytic reaction and eliminates the temperature effect. In this study, the mutual hydrolyzed reaction of NaBH4 and waste Al provides ecofriendly environment, low cost and enables to achieve higher HG rate and further uses for portable/mobile fields. 相似文献
2.
论述了炼铁-炼钢界面的紧凑衔接技术,涉及多维物质流的衔接、传递、匹配及缓冲等过程。从各角度综合分析得出,该界面衔接布置紧凑,占地面积小,实施MES系统的“在线铁水罐跟踪系统”使炼铁-炼钢界面减少了铁水罐周转个数,相对传统方式的铁水包输运方式,保温剂使用量平均减少了0.483 kg/t(铁),铁水入炉温度提高约60 ℃。同时,确保了100%的“一罐到底”命中率,大幅节省了耐材费用,具有显著的经济效益和社会效益。 相似文献
3.
加强土地市场监管 ,必须着重从体制、机制和法治上解决问题。一要完善法规体系 ,真正做到有法可依。二要健全执法体系 ,真正做到有法必依。三要扩大执法成果的应用 ,建立快速执法机制。四要建立巡查责任制 ,及时制止违法行为发生。 相似文献
4.
介绍了CAD CAM网站中动态页面的设计。为了实现用户与网站的交互功能 ,在词汇查询与问题讨论部分采用ASP技术 ,使本站能够根据用户的需求在数据库中调取相关数据 ,动态生成页面。 相似文献
5.
Sivakumar Palanivelu Wim Van PaepegemJoris Degrieck Bruno ReymenJean-Marie Ndambi John VantommeDimitrios Kakogiannis Jan WastielsDanny Van Hemelrijck 《Engineering Structures》2011,33(6):1966-1987
This article deals with the experimental and numerical blast study on a single empty recyclable metal beverage can. The idea is to make a macro-foam (sacrificial cladding structure) out of these cans to protect the main load bearing members of civil engineering structures from the air blast load. Close-range free air blast tests have been conducted to understand the crushing behaviour and the energy absorption of a single empty beverage can in detail. To conduct such an air blast test a special small-scale test set-up was designed and manufactured. The effect of skin plate surface area and its nature on the blast parameters is studied. Furthermore, the effect of inertia of the skin plate on the crushing performance of the beverage can is evaluated. Tests have been conducted with different plates (made of aluminium and sandwich composite materials) with different masses which represent the skin plate of the proposed sacrificial structure. The measured blast parameters from the experimental tests were compared with ConWep predicted data. Furthermore, the influence of the finite surface area of the skin plate on the clearing of the reflected pressure waves was also studied. The deformation behaviour and the corresponding energy absorption of empty beverage cans were captured. During the experimental blast tests it was observed that a part of the total reflected impulse (∼30%) was lost before it transfers to the non-sacrificial structure. Hence, in order to investigate this phenomenon Eulerian-Lagrangian coupled analyses were conducted using Hydrocodes. The results from these analyses showed that the diffraction and ground reflected pressure wave caused the loss in impulse. The results from the numerical studies have been compared and validated with the experimental results. 相似文献
6.
The purpose of this research was to determine the effects of the packaging materials and size on the stability of monomeric anthocyanins, polyphenols, antioxidant activity, ascorbic acid, colour index and hydroxyl methyl furfural (HMF) during the 12‐month shelf life of sour cherry nectars at 4 °C and 20 °C. Sour cherry nectars were aseptically filled out into packaging of different sizes and materials. The packaging included cartons of two different sizes (200 and 1000 mL) and aluminium cans (330 mL). Results showed that the nectars were of better quality when stored at lower temperatures. HMF generally increased significantly for all nectars during storage. Conversely, the total polyphenol content and the antioxidant activity of the nectars stored in aluminium cans and the larger‐sized carton packaging decreased during storage. Lower anthocyanin loss and colour change were found in the nectars stored in aluminium cans. However, the better packaging material was found to be the large‐sized carton package when HMF was analysed. 相似文献
7.
The catch can method is traditionally used for evaluating performance of drip systems. Two variations of this method are commonly applied in laboratory testing of drippers: the sequential and the simultaneous method. This study compared uniformity and measurement uncertainty of the two methods, with the overall aim of improving irrigation water management. The simultaneous method was found to have a lower coefficient of variation (Cv) and measurement uncertainty, indicating that it is more accurate than the sequential method. In all the tests, however, the Cv was determined to be <5%, which is acceptable as per the current reference standard. 相似文献
8.
5182铝合金罐盖料生产工艺技术 总被引:1,自引:0,他引:1
阐述了5182铝合金罐盖料的生产和应用现状。对5182铝合金罐盖料的化学成分及各合金元素的作用、Fe和Si杂质的控制,生产中熔体处理、铸造、均匀化处理、热轧、冷轧、热处理、表面处理工艺技术问题进行了评述。 相似文献
9.
从铣刀的安装、铣削方式、刀具切削角度的组合、螺旋角的选择、铣刀轴线的位置、修光刀片的使用等方面,讨论了硬质合金面铣刀的合理使用技术。 相似文献
10.