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31.
消力戽在低佛氏数水流中的应用 总被引:1,自引:0,他引:1
结合左江水利枢纽的兴建时消力戽进行了研究和实践,介绍低佛氏数水流特点和低佛氏数水流消能工的研究现状,左江工程的运行资料证明消力戽应用于低佛氏数水流消能是成功的。 相似文献
32.
Rice husk generated as a by-product of rice processing is an important energy resource. The availability of this resource in India has been assessed and the technologies for exploitation of its energy potential in rice processing industry discussed. Nomographs have been developed for estimation of the husk required to meet the energy demand of parboiling, drying and milling operations. The unit cost of electricity using rice husk gasifier-based power generation systems has been calculated and its financial feasibility assessed in comparison with utility-supplied and diesel-generated electricity. With the cost and efficiency data assumed here, the unit cost of electricity produced by rice husk gasifier-dual fuel engine-generator system varies between Rs 2/kWh and Rs 7/kWh. (Note: 35 Rs approximates to $US 1.) 相似文献
33.
MALHIREDDY INDUMADHAVI V. AGTE 《International Journal of Food Science & Technology》1992,27(2):221-228
The average diet in most developing countries is predominantly cereal based. Wheat, rice and millets are major staple foods. Although these diets are sufficient in iron, their low bioavailability is one of the most significant factors for iron deficiency anaemia. Traditional techniques like fermentation show promise in improving iron bioavailability. In vitro ionizable iron was estimated in 31 different combinations of rice, wheat, sorghum, black gram, bengal gram, green gram and coriander in five replicates with or without, fermentation in steamed products. Results indicate that in general cereal pulse combination and fermentation significantly ( P <0.05) increase the per cent ape of ionizable iron. Combination effects dominated in rice whilst fermentation dominated in sorghum. There was a significant reduction ( P <0.05) in phytate phosphorus on fermentation but no loss of tannin. 相似文献
34.
N. K. Savant P. S. Ongkingco I. V. Zarate F. M. Torrizo P. J. Stangel 《Nutrient Cycling in Agroecosystems》1991,28(3):323-331
A plunger-type, completely hand-operated applicator prototype, made of polyvinyl chloride (PVC), for deep placement of urea briquettes (UB), i.e., pillow-shaped urea supergranules with edges, in line transplanted rice has been developed for use by small-scale rice farmers. The field evaluation of the applicator was conducted in the Philippines during the 1989 dry season. The applicator consistently placed UB at proper depth (7 to 8 cm), which resulted in low concentrations of urea N (<7 ppm) in about 4 cm of floodwater 1 day after placement. These findings indicated that the prototype worked properly. Average work output of the applicator was 0.20 ha workday–1 and may increase with practice. The yields of irrigated transplanted rice in the field trials show that agronomic efficiencies of hand-placed UB and applicator-placed UB were equal and were superior to those of split-applied prilled urea. 相似文献
35.
着重分析空调压缩机采用新的环保型冷媒体后,常规结构滚针轴承的破坏情况,提出了冲压滚针轴承新的结构改进设计及其开发和性能比较结果,为今后新冷媒体空调压缩机的广泛使用,提供了有利的保证。 相似文献
36.
圆筒形铸件缩松缩孔的产生原因及解决方法 总被引:1,自引:0,他引:1
针对圆筒形铸铁辊体冒口端面产生的缩松、缩孔缺陷,进行了举例说明、系统分析,找到了缺陷产生的原因及影响因素。通过解决措施的应用与实施,有效地克服了圆筒形辊体铸件冒口端面产生的缩松、缩孔缺陷,同时应用到其它大型圆筒形铸件中,都得到了良好效果。 相似文献
37.
Mechanical properties and thermal stability of epoxy foams filled with white and black rice husk ash were studied. Epoxy foams were prepared from a commercial system and filled with different amounts of both the ashes (0, 6.8, 12.8, 18.0, and 22.7 wt %). The incorporation of both the ashes modified the final morphology of the foam, decreasing the average cell size and increasing the number of cells per volume unit. For all filler percentages used, the specific modulus and strength results showed that the white ash is more effective as reinforcing agent than the black ash. The initial degradation temperature was not affected by the content and type of ash used as the filler. The integral procedure decomposition temperature, weight loss, and char residue results were related to the ash type and atmosphere used in the thermogravimetric analysis. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci, 2006 相似文献
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