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71.
72.
M. Kunz 《Scientometrics》1988,13(1-2):25-33
Haitun's conjectures about specific properties of information distributions are questioned. It is shown on linguistic material that the opening of a closed counting scale changes the skewness of distribution in a way which contradictsHaitun's suggestions. Negative power distributions are time dependent and can be explained as density measures of fractal clusters and are not specific to the social sciences. 相似文献
73.
The first stages of infrared drying of waterborne coating systems are controlled by the evaporation of their volatile components. In order to analyse the kinetics of drying during IR radiation, the evaporation behaviour of water and other solvents of waterborne coatings are investigated using a combined gravimetric and photoionization technique. The resulting specific evaporation rates under IR radiation are compared with those obtained by thermal annealing. It is shown that in the case of IR radiation heating of water, the mass transfer coefficients are much higher than by thermal annealing at the same driving potential. The dependence of the water absorption rates and the mass losses of different solvents on the humidity of the air was also determined. 相似文献
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76.
Leaves are an important dietary source of carbohydrates and protein, and an especially rich source of calcium for bats. Most studies of leaf eating by fruit bats have suggested that only male bats feed on leaves. In this study, 23 wild-caught Tongan fruit bats (Pteropus tonganus) were used in feeding trials conducted in an outdoor enclosure. The number of leaves and percentage of each leaf eaten were recorded for each bat on a daily basis, and these data were then multiplied by a calcium constant that was derived from a chemical analysis of leaves from Callophylum neo-ebudicum. Leaves of C. neo-ebudicum that were available in the enclosure were consumed by 82.7% of the bats. Overall, males consumed leaves in greater quantities and with higher frequency than females. Bats that consumed leaves on a regular basis consumed up to 46% more calcium to their diet compared with bats that did not regularly consume leaves. Leaves may represent a readily available, widely used, concentrated source of minerals for foraging bats, and have the potential to contribute significantly to the total amount of ingested calcium. 相似文献
77.
Experimental charge and current measurements have recently been performed on an aircraft when it was exposed to the transient electromagnetic fi'eld of an electromagnetic pulse (EMP) simulator. These new data allow a test of the predictive capabilities of the three-dimensional finite-difference method for realistic aircraft simulator test problems. In the paper, the workings of the threedimensional finite-difference method and its required inputs and sensitivity to variations in the inputs are discussed in sufficient detail to enable others to employ the method. A companion paper compares the experimental measurements to predictions for a large variety of measurement locations. Agreement is shown to be good for all major response measurements and satisfactory for a number of other measurements. 相似文献
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L. P. Zalukaev V. I. Pivnev I. V. Grinberg M. E. Petrikovskaya E. D. Dubovyi N. A. Kraevskii N. M. Nemenova M. P. Khokhlova M. S. Dul'tsin I. A. Kassirskii M. O. Raushenbakh R. H. Dalitz W. Kunz J. Schintlmeister C. M. Smith D. N. Chesney M. O. Chesney P. A. Lykourezos B. Rossi W. R. Corliss S. Glasstone W. F. Hilton C. E. Roth M. Ash V. A. Kuznetsov L. T. Chadderton G. Friedlander J. Kennedy J. Miller E. Schwarz C. C. Washtell S. G. Hewitt B. J. Williams W. B. Mann S. B. Garfinkel S. C. Pearce D. D. Glower E. R. Popescu 《Atomic Energy》1967,22(2):170-191
80.
Experimental isotherms indicate that thiocyanate and nickel cyanide complex (tetracyanonicklate (II)) adsorb to an equal extent from synthetic and actual waste solutions at loadings below 10 mg/g carbon. Loading of nickel hexammine complex is an order of magnitude less. Adsorption of the divalent nickel cation is strongly pH dependent and is believed to be a chemisorption by precipitation or reaction on the carbon surface. In pure solution, ferrocyanide (hexacyanoferrate (II)) adsorption was comparable to that of thiocyanate or nickelocyanide, but adsorption from the waste liquor tested was negligible. This difference may be due to solvation of ferrocyanide with methanol in the wastewater to form a species with entirely different adsorption characteristics. Chemical oxygen demand (COD) values were obtained for several of the pure materials (SCN?, 1.1; Fe(CN)6?4, 0.5; Ni(CN)4?2, 0.4 mg ion) and the wastewater to monitor adsorption of organic background materials. 相似文献