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11.
The effect of natural convection on forced convection in a horizontal flow was investigated during zinc electrodeposition on a horizontal electrode facing upward in a channel. The previous findings of Tobias and Hickman [1] are confirmed. A secondary flow in the form of roll cells whose axes are parallel to the flow direction is formed at some distance from the leading edge. This distance depends linearly on the flow velocity through the critical Rayleigh number for the onset of natural convection across the diffusion boundary layer. Striated zinc deposits reveal the imprint of the secondary flow on the planar cathode facing upward. 相似文献
12.
Ten male and ten female brown trout (Salmo trutta L.) ranging in weight from about 500 to 3500 grams were caught in Lake Ontario. Opposite sides of each individual fish were randomly processed and trimmed to yield skinned or unskinned fillets. Skinning resulted in an increase in the average concentration of total mercury in the fillets of fish of either sex but the increases were not significant .
With the exception of the unskinned fillets of the male fish, the concentration of mercury in the fillets increased significantly as the weight of the fish of either sex increased. The fillets of the male fish appeared to be higher in mercury than that in the corresponding fillets of female fish of comparable weight. In all instances, the concentrations of mercury in skinned and unskinned fillets were well below the 1 ppm fresh weight action level of the U.S. Environmental Protection Agency. 相似文献
With the exception of the unskinned fillets of the male fish, the concentration of mercury in the fillets increased significantly as the weight of the fish of either sex increased. The fillets of the male fish appeared to be higher in mercury than that in the corresponding fillets of female fish of comparable weight. In all instances, the concentrations of mercury in skinned and unskinned fillets were well below the 1 ppm fresh weight action level of the U.S. Environmental Protection Agency. 相似文献
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14.
Three instrumental techniques, cone penetrometry, probe penetration and Instron TPA, were compared as means to describe butter spreadability. A factorial experiment was set up to examine the consistency of winter and summer butter, mechanically worked and unworked, before and after storage and at two measurement temperatures, 5° C and 15° C. Probe penetration provided useful information on the relaxation behavior of butter, as well as contributing to the fundamental knowledge of butter structure. The Instron TPA has the advantage of a link with an internationally recognized system of texture analysis. The technique was also found to show greatest potential as a method to assess the effectiveness of mechanical treatment of butter. Cone penetrometry results were converted to yield values and in conjunction with Haighton's ready reckoner scale of assessment provided a simple and rapid method to describe butter spreadability. 相似文献
15.
LEONARD H. WEINSTEIN JOSEPH F. OSMELOSKI MICHAEL RUTZKE ALFRED O. BEERS JOHN B. McCAHAN CARL A. BACHE DONALD J. LISK 《Journal of Food Safety》1989,9(4):291-300
Forage grasses and legumes growing in the soil covering four coal fly ash landfill sites in Central New York were sampled and analyzed for 20 elements. Selenium, boron and molybdenum were most consistently higher in concentration in these crops than the corresponding control plants sampled from adjacent upwind locations. Legumes absorbed greater amounts of these elements than grasses probably owing to their deep-rooted penetration of the fly ash layer below. Factors affecting the extent of absorption of these elements by the crops and the agricultural significance as related to grazing farm animals are discussed. 相似文献
16.
LARRY E. CHASE RICHARD H. ECKERLIN JOSEPH G. EBEL JR. GEORGE A. MAYLIN WALTER H. GUTENMANN DONALD J. LISK 《Journal of Food Safety》1987,8(4):245-253
Residues of the miticide, dicofol, used in orchards, as well as p,p'-DDE a metabolite of p,p'-DDT present as an impurity in dicofol, were found in each commercial apple pomace sampled at several locations in Central New York. Traces of dicofol and p,p'-DDE were found in milk when cows were experimentally fed one of the pomaces for 9 days. These compounds were also detected in the milk of cows which had been fed by a dairy farmer on a practical basis for several months. It was judged that the milk residues were too low to be of health significance to consumers. 相似文献
17.
An appreciable percentage of electric power is generated by oil-fired power plants. The ash resulting from such plants is typically very high in elements such as vanadium, nickel, aluminum and molybdenum. Oil bottom ash and fly ash when disposed or fly ash fallout from such power plants could result in absorption of such metals by agricultural crops. Swiss chard (Beta vulgaris L.) was grown in potted soils amended with oil bottom ash and fly ash at 2% and 1% (w/w), respectively. The crop absorbed significantly higher concentrations of each of the metals as compared to those in the control crop grown on soil alone. Higher levels of the ashes in soil resulted in phytotoxicity to the swiss chard . 相似文献
18.
19.
DONALD R. MOSCATO 《国际生产研究杂志》2013,51(3):401-406
Given the objective of determining the degree of part commonality in a product line, this study discusses several methods of analysis which are possible. The use of the entropy measure, H= ? σpi log pi, is investigated as a plausible alternative to current procedure. The methodology will incorporate a simulation of several types of distributions of part usage which might occur in a typical application. An analysis of the results will compare the entropy approach with existing practice. 相似文献
20.