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991.
The online version of the original article can be found at 相似文献
992.
On The Measurement of Temperature in Material Removal Processes 总被引:5,自引:0,他引:5
Because it is key to understanding the performance of material removal processes and resultant workpiece quality, the measurement of temperature during material removal is done extensively. We review several widely used temperature measurement methods and show how they can be applied to temperature monitoring during material removal. Since there is little documentation on measurement uncertainties as relates to material removal, this paper outlines the physics of each method, detailing the sources and evaluation of uncertainty. Finally, using criteria critical in measuring material removal, methods are compared, and the results presented in guide-format for participants in this field of work. 相似文献
993.
Metal Science and Heat Treatment - 相似文献
994.
Prokoshkina V. G. Kaputkina L. M. Svyazhin A. G. 《Metal Science and Heat Treatment》2002,44(9-10):414-415
Metal Science and Heat Treatment - 相似文献
995.
996.
997.
An exact solution inside, outside, and within two arbitrary concentric spherical shells is presented for an impinging monochromatic linearly polarized electromagnetic wave. Specifically, the solution was found for a double-shell spherical acrylic plastic enclosure irradiated with 2450-MHz microwaves. The enclosure is used as an environmentally controlled exposure chamber for experimental animals during microwave irradiation. The analysis shows that an air foamed material, such as styrofoam, would be a better material than either Plexiglas or Teflon, provided it is sufficiently durable. 相似文献
998.
Kester Bruce E. Gilliland J. L. Fritts Stewart S. Bell Zeb G. Smith Hubert Berby Richard H. 《Industry Applications, IEEE Transactions on》1972,(1):8-18
MAN is but a part of the universe; his capabilities make him a significant link, in the cycle of life. To ensure this life, man must live in harmony with his environment. Recently, a disharmony has been discovered which could have grave effects upon the existence of man. It appears that man in his great thrust forward is destroying his own environment. The gravity of this threat to man's own existence carries some intrinsic problems of its own: man must allow his reason rather than his emotion to take command. 相似文献
999.
R.?L.?M.?SchilsEmail author A.?Verhagen H.?F.?M.?Aarts L.?B.?J.??ebek 《Nutrient Cycling in Agroecosystems》2005,71(2):163-175
Ruminant livestock systems are a significant source of greenhouse gases (GHGs). Thus far, mitigation options for GHG emissions mainly focused on a single gas, and are treated as isolated activities. The present paper proposes a framework for a farm level approach for the full accounting of GHG emissions. The methodology accounts for the relevant direct and indirect emissions of methane, nitrous oxide and carbon dioxide, including carbon sequestration. Furthermore, the potential trade-off with ammonia volatilisation and nitrate leaching are taken into account. A ruminant livestock farm is represented with a conceptual model consisting of five pools: animal, manure, soil, crop and feed. The carbon and nitrogen inputs, throughputs and outputs are described, and the direct emissions are related to the carbon and nitrogen flows. The indirect emissions included in the methodology are mainly carbon dioxide emissions from energy use and nitrous oxide emissions related to imported resources and nitrogen losses. The whole farm approach is illustrated with a case of two dairy farms with contrasting livestock density and grassland management. It is shown that the inclusion of carbon sequestration and all indirect emissions have a major impact on the GHG budget of the farm. For one farm, the effect of four mitigation options on the GHG emissions was quantified. It was concluded that a whole farm approach of full accounting contributes to a better insight in the interactions between the carbon and nitrogen flows and the resulting emissions, within and outside the farm boundaries. Consequently, the methodology can be used to develop efficient and effective mitigation strategies. 相似文献
1000.
Potentiometric titration of long chain quaternary ammonium compounds using sodium tetraphenyl borate
C. N. Wang L. D. Metcalfe J. J. Donkerbroek A. H. M. Cosijn 《Journal of the American Oil Chemists' Society》1989,66(12):1831-1833
Current methods for determining the activity of long chain quaternary ammonium compounds (QACS) are based either on dye partition,
titration, or colorimetric analysis. The two major disadvantages of these methods are the disparity of partition coefficients
among differently constituted QACS and the difficulty in detecting visual end points. Some potentiometric titration methods
for QACS have been reported in the literature. However, back titration techniques, as well as complicated electrode systems,
are generally involved.
A new potentiometric titration system is presented which uses aqueous sodium tetraphenylborate (TPB) solution as a titrant
and a platinum-platinum electrode system to detect the end point. Standard potentiometric titration instruments may be used
for this method. This new potentiometric method is superior in precision and accuracy to visual (colorimetric) methods.
Original version presented at the 1986 Annual AOCS Meeting in Honolulu, HI. 相似文献