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91.
James L. Schoenfelder 《国际自然能源杂志》2013,34(4):193-198
The paper describes a residence designed and built to demonstrate that active and passive solar homes could be economically by conventional home builders. The systems were designed for simplicity and cost effectiveness. The home was built in 56 days with conventional building materials and built by labourers with no particular training in energy efficient building techniques. After one season of operation the energy use data shows impressive performance. The auxiliary fuel requirement for the heating season was only 0.035 MJ/m2°C-day (1.72 Btu/ft2°F-day). Economically the home is equally impressive. An independent appraiser of the home valued the construction at US $67 500. In reality the home cost US $59 000 including contractor's overhead and profit. Subtracting from this the amount US $4000 for the Federal Solar Tax Credit results in an owner cost of US $55 000. The project demonstrated that given proper consideration for design, construction techniques, and solar systems integration, a solar structure need not cost more than conventional construction. 相似文献
92.
Evolution of the oxidative stability,bio‐active compounds and color characteristics of non‐thermally treated vegetable pâtés during frozen storage
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93.
94.
蔬菜工厂化生产是当代世界先进的科学技术。本文介绍蔬菜工厂化生产的主要关键技术——现代化温室群、工厂化育苗和无土栽培的发展状况,并预示我国蔬菜工厂化生产技术的发展趋势。 相似文献
95.
改性橡木宛栲胶鞣制牛皮沙发革工艺的探索 总被引:4,自引:0,他引:4
探索了用橡Wan栲胶植鞣黄牛皮沙发革的工艺,分析测试了所鞣坯革的物理及感观性能,为植鞣牛皮轻革产品提供了一些理论与实验依据。 相似文献
96.
赵俊廷 《河南工业大学学报(自然科学版)》2002,23(3):15-18
对AOT/异辛烷反胶束溶液萃取大豆中的蛋白质的性能进行了研究 .结果表明 :蛋白质的萃取效果取决于反胶束的w0 、水的pH值和KCl浓度 ,且蛋白质是否能进入反胶束内 ,与反胶束的大小无关 ,而主要受极性核内水的性质的影响 相似文献
97.
离子选择电极法测定蔬菜中氟化物的含量 总被引:2,自引:0,他引:2
采用离子选择性电极法测定蔬菜中氟化物的含量,方法简单、快速、结果可靠. 相似文献
98.
根据美国油脂化学协会Ce—1—62法,谷物比学协会审批方法AACC方法58—18法,采用气相色谱仪对新疆地区的植物油的脂肪酸组成进行了测定分析。并与四川部分地区油菜子进行了比较。 相似文献
99.
A.G. Fikiin 《International Journal of Refrigeration》1983,6(3):176-181
Increasing the rate of fruit and vegetable cooling is of economic significance for the following reasons: biochemical and microbiological processes are quickly suppressed; surface mass-exchange with ambient air is slowed down; power consumption is reduced, and the freezing output of cooling equipment and installations is increased.It was assumed that the fruits and vegetables in crates were arranged regularly and covered with thin paper of a negligible small thermal resistance in order to eliminate the infiltration of cold air within the layers. Crates were arranged on a pallet so that they touched horizontally. Thus, the packages form plates above and below the cooling air flow. Heat-exchange with a one-dimensional temperature field is established.It was found that intensification of cooling can be achieved by increasing the speed of cooling air as well as by stopping the process at a higher final temperature. Increasing the speed up to 5 m s?1 shortens the time of the process by a factor of two compared with the low speeds (0.3–0.5 m s?1) which are normally used. The product can be cooled until the temperature in the layer centre reaches 5°C, and the surface temperature about 2°C, which is low enough. Afterwards the cooled product is transferred to a freezing chamber or to a van-freezer. This factor results in a further halving of the cooling time. The combined effect of the two factors shortens the duration of the process by about 75% and increases the output of the cooling equipment from 3.5 to 4 times. 相似文献
100.