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911.
Using the data from vendors and open literature, we have constructed a preliminary cost model to predict the cost of liquid hydrogen (LH2) from water electrolysis. The model has been applied to two LH2 plants. Both have a production rate of 10 886 kg day−1. The first plant (Plant 1) consists of a tank-type electrolyzer and a liquefier and runs all day at the base-load (or equivalent base-load) power rate. The second (Plant 2) consists of a tank-type electrolyzer, a liquefier, a compressor, and storage vessels. The electrolyzer and the compressor shall run only during the off-peak hours at the off-peak power rate. However, the liquefier shall run all day at the base-load (or equivalent base-load) power rate. The costs of LH2 from both plants are presented. Unless the base-load power rate is high and the off-peak power rate is substantially low, Plant 1 appears to be economically more feasible than Plant 2.  相似文献   
912.
The effect of diet on the lethality of 1, 2-dimethylhydrazine (DMH) injections was investigated using Swiss mice. Mortality was highest when mice were fed a nutrient-diluted/high-fat diet, was intermediate with a nutrient-diluted/low-fat diet and was lowest with laboratory chow. Wheat bran was not protective. Mice developed tolerance to DMH after receiving several injections of progressively increasing dose.  相似文献   
913.
The rôle of saponins in the undesirable sensory properties of the dried pea P sativum is reported. The sensory properties of isolated soyasaponin I are defined and described as bitter, astringent and metallic. The distribution of saponin in various air-classified pea flour fractions shows that the protein-rich fraction may contain sufficient saponin to cause undesirable tastes.  相似文献   
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918.
Weekly storage of coolness in heavy walls (walls with large thermal inertia or large characteristic time constants or low Fourier numbers) was investigated numerically by considering one-dimensional heat conduction through the walls. The study consisted of first analyzing the heat flow through a single wall and considering various boundary conditions on the inside. The boundary conditions were: constant inside air tempeture throughout the day, variable inside air temperature on a 24-hour cycle, and variable inside air temperature on a 48-hour cycle. Next, the heat flow through walls was studied through a thermal network analysis of a simple building. In this case it was assumed that the ambient air temperature (following a periodic distribution) was increased suddenly and followed this new distribution for many days thereafter.It was concluded that walls with high thermal inertia or time constant can store coolness for several days. The larger the time constant of the wall (for example adobe as compared with brick) the longer it takes for the wall temperature to reach a steady periodic distribution after the change has occurred. However, because of low thermal conductivity of adobe, the retrieval of the stored coolness in these walls is slow, and the mean daily temperature of the room air in the adobe building does not change appreciably beyond seven days after the change. Increase of the wall thickness beyond 50 cm does not improve the thermal performance of the building significantly.  相似文献   
919.
A method of calculating the temperature resistance coefficient and its temperature dependence for resistive materials in the approximation of a matrix-statistical structure is outlined.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 3, pp. 477–481, September, 1985.  相似文献   
920.
We have developed a novel immunoassay method using bacterial magnetic particles for the determination of immunoglobulin G (IgG). Fluorescein isothiocyanate (FITC) conjugated anti IgG-bacterial magnetic particles were prepared. The fluorescence quenching caused by agglutination of FITC-anti IgG antibody-bacterial magnetic particle conjugates was measured by using a fluorescence spectrophotometer. The aggregates based on specific immunoreaction were separated by a gelatin solution. The aggregation of bacterial magnetic particle conjugates was enhanced by application of a magnetic field. The relative fluorescence intensity correlated linearly with a concentration of IgG in the range 0.5-100 ng/mL.  相似文献   
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