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排序方式: 共有1592条查询结果,搜索用时 15 毫秒
1.
《International Journal of Hydrogen Energy》2020,45(13):7641-7646
The depletion of non-renewable energy resources such as fossil fuels urge the human society to concentrate more on renewable energy including production of biological hydrogen (H2) from algae. Biological hydrogen or biohydrogen is one of the cleanest and efficient alternate energy sources for human needs. It is a well-known fact that hydrogenase (H2ase) will work in anoxic condition which is the key enzyme in H2 generation from photosynthetic algae or advanced plants. Keeping in view the significance of anoxic condition, the present study deals with screening of three oxygen scavengers/removers such as sodium sulfite (Na2SO3), sodium metabisulfite (Na2S2O5) and sodium dithionite (Na2S2O4) individually along with universal tris-acetate-phosphate (TAP) medium for improvement of biohydrogen production in green alga Chlorococcum minutum (C. minutum) under in vitro conditions. To the best of our knowledge, for the first time improvement in hydrogen production was achieved using sodium sulfite and sodium metabisulfite individually with algal cultures. Efficient photobiological H2 production was observed at 24 h in C. minutum in the presence of all the three oxygen scavengers when compared to untreated samples via limiting the oxygen levels but output was more with sodium sulfite treatment. Particularly 0.8 mM Na2SO3 is best for enhancement of H2 production at 24 h when compared to other two scavengers and this may be due to high oxidation state and more electron negativity of this compound. Apart from augmentation in H2 production in this species, present screening may also be helpful for researchers working in the area of biological H2 generation. 相似文献
2.
废热锅炉是Cassle合成氨技术中的关键设备,本文以某改造项目Cassle技术废热锅炉为研究对象,阐述了废热锅炉的结构特点,结合化工厂反馈的问题,针对关键工序提出了改进措施,为制造类似结构和要求的产品积累了宝贵经验。 相似文献
3.
《International Journal of Hydrogen Energy》2020,45(1):230-262
The Co-Current reactor gasifier is a promising technique, owing to its good performance and less residue content. Even though it can be used only for low moisture feedstock, it is needed improvement by incorporating modifications in the design of reactor, feeding system, air supply system, preheating air or feedstock, discharge system, recirculation technique, and co-gasification. Many of the researchers found that various improvement methods have been done to improve the performance of the gasifier at different operating condition. Therefore, in this paper a detailed review has been made to study about that developments of Co-Current gasifier and their effects on the performance of the gasifier. Further to improve the performance a suitable method for the gasifier is identified. A comparision with various methods reveals that design modification showed better performance, higher producer gas yield and less pollution. 相似文献
4.
介绍了一种快速更换麦尔兹窑喷枪的方法,并分析了喷枪烧损的原因,以及提出了如何延长喷枪寿命的意见。 相似文献
5.
通过优化滑板材质、调整滑板体积、优化滑板形状、改进钢包滑动机构等措施对原滑板进行了改进,改进后的滑板连滑率达到了100%,使用寿命达到了4次,基本上满足了生产要求。 相似文献
6.
近段时间来,社会主义新农村建设正在全国各地如火如荼地展开着,如何在村庄建设规划中进行社会主义新农村建设,如何将规划理念落实在实处,该文结合湖南长沙县石塘铺村村庄规划实例,进行一些探讨性的论述,希望能起抛砖引玉之作用. 相似文献
7.
对旧建筑进行改造、加建,使旧建筑筑与新建筑通过一种创造性的方式结合在一起,具有非常现实的意义和巨大的价值。该文试国通过盐城师范学院图书情报中心的设计探索,讨论在原有校园肌理和新校园规划轴网叠合的基础上,积极寻求新老建筑优化交接的可能性,以简洁理性的方式最大限度的适应环境制约,创造独特的藏阅空间。 相似文献
8.
压力释放阀动作原因分析及优化措施和改进设想 总被引:1,自引:0,他引:1
本文中作者介绍了某电厂220k V主变压器的一起压力释放阀动作的原因分析、处理过程,引出了运行监视的优化措施,并提出一种在线试验的设想。 相似文献
9.
10.
Gang Shi Xishun Li Zhiyun Feng Luyan Wu 《Polymer-Plastics Technology and Engineering》2015,54(9):881-888
Copolymers of poly(n-butyl methacrylate-co-glycidyl methacrylate) were prepared by a free radical polymerization. The structures of the copolymers were characterized. The copolymers could be added to a powder epoxy resin (E663) to form modified epoxy resins. It was found that toughness of the cured modified epoxy resins were greatly improved, impact strength increased 3 times and fracture elongation increased 20% compared to the cured unmodified E663 resin. This is because that the copolymers had epoxy groups and flexible butyl groups, the former were involved in cross-linking reaction of the E663, and the latter made contribution to the toughness improvement. 相似文献