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11.
Comparative studies on Ar and He closed-cycle MHD power plants combined with fossil fuel are performed. The sizes of a regenerative heat exchanger and a boiler are expected to be smaller for He than for Ar. The pressure loss of a working gas in a regenerative heat exchanger is reduced for He. The purification subsystem for He is expected to be more compact and economical than that for Ar; but a larger compressor is required for He than for Ar. 相似文献
12.
根据斯涅尔定律和菲涅尔公式阐述清水衬底法消除玻璃下界面手印或玻纹的影像,以及用偏振光,紫外线拍摄玻面痕迹的方法和机理。 相似文献
13.
T.F. Zabel 《臭氧:科学与工程》1985,7(1):11-30
Only two water works in the UK apply ozone at present as part of their treatment, onefor taste and odor control and theother forcolor removal. Forthetwo applicationus ozone was the most economical option at thetime theplants were installed andozone has been successful for the purpose for which it was designed. 相似文献
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15.
On irrigation schemes with rotational irrigation systems in semiarid tropics, the existing rules for water allocation are based on applying a fixed depth of water with every irrigation irrespective of the crops, their growth stages, and soils on which these crops are grown. However, when water resources are scarce, it is necessary to allocate water optimally to different crops grown in the irrigation scheme taking account of different soils in the command area. Allocating water optimally may lead to applying less water to crops than is needed to obtain the maximum yield. In this paper, a three stage approach is proposed for allocating water from a reservoir optimally based on a deficit irrigation approach, using a simulation-optimization model. The allocation results with a deficit irrigation approach are compared for a single crop (wheat) in an irrigation scheme in India, first with full irrigation (irrigation to fill the root zone to field capacity) and second with the existing rule. The full irrigation with a small irrigation interval was equivalent to adequate irrigation (no stress to the crop). It is found that practicing deficit irrigation enables the irrigated area and the total crop production in the irrigation scheme used for the case study to be increased by about 30–45% and 20–40%, respectively, over the existing rule and by 50 and 45%, respectively, over the adequate irrigation. Allocation of resources also varied with soil types. 相似文献
16.
The catalytic activity of fresh Pd and Pt catalysts supported on γ-alumina in the complete oxidation of CH4 traces under lean-burn conditions was studied in the presence or the absence of water or H2S. Steam-aged catalysts were also studied in order to simulate long-term ageing in real lean-burn natural gas fuelled vehicles (NGVs) exhaust conditions. Without water or H2S added to the feed, Pd catalysts exhibit a superior catalytic activity in methane oxidation compared to Pt ones, whatever the catalysts were fresh or aged. The addition of 10 vol.% water vapour to the feed strongly affects the activity of the fresh Pd catalyst, thus being only slightly more efficient than the fresh Pt one. H2S has a strong poisoning effect on the catalytic activity of Pd catalysts, while Pt catalysts are more resistant. The fresh H2S-poisoned Pd/Al2O3 catalyst was studied by TPD in O2/He. Poisoning species decompose above 873 K as SO2 and O2 in relative concentrations consistent with the decomposition of surface sulphate species. However, a treatment in O2/He at temperatures as high as 923 K does not allow the complete regeneration of the catalytic activity of H2S-poisoned Pd/Al2O3. A mechanism involving the poisoning of PdO by sulphate species is proposed. Different diffusion processes by which these sulphate species can migrate back and forth between PdO and the support, depending on the experimental conditions, are suggested. 相似文献
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18.
文章介绍了宝钢自备电厂在改善锅炉燃烧工况,控制锅炉水冷壁结焦所采取的技术措施,分析了锅炉水冷壁结焦量与锅炉二次再热器烟气出口平均温度的关系,为解决锅炉水冷壁结焦所引发的二次再热器超温爆漏问题提供了依据。 相似文献
19.
利用理想的地质体积模型和电阻率测井的供电电流流过模型的导电机理,推导出一种不需要含水饱和度参数即能定量计算含水饱和度的方法,即岩性类比解释法。经过初步实践,该方法应用于砂泥岩地层的测井分析,效果良好。 相似文献
20.
岩心PI值试验研究及应用 总被引:5,自引:0,他引:5
主要论述了在多功能采油化学用剂评价仪上进行的岩心PI值试验的步骤,现象及结论。重点考察了岩心PI值与渗透率、流量及注入截面面积的关系;平行管岩心复合PI值和其中单管岩心PI值的关系。 相似文献