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81.
The results of the development of a four-degree-of-freedom, lumped parameter model of the vibration response characteristics of the human hand are presented. For this study dynamic compliance measurements were made on 75 foundry workers. Curve fitting techniques were then employed to identify the values of the model parameters that yielded empirically generated dynamic compliance curves that correlated well with the measured dynamic compliance values. The agreement was good between 20 Hz and 1000 Hz in the X- and Y-directions. The agreement was good between 20 Hz and 1000 Hz in the Z-direction. 相似文献
82.
83.
A Celite-sodium borohyride column has been used to reduce micromole amounts of a variety of simple carbonyl compounds to the corresponding alcohol in fair to excellent yields. The procedure is relatively rapid and easy involving only the application of a hexane solution of the carbonyl compound to the column and collection of the effluent containing the alcohol. A column constructed in a melting point capillary suitable for the reduction of microgram amounts of carbonyls is also described. 相似文献
84.
J. L. Musfeldt John R. Reynolds D. B. Tanner Jose P. Ruiz Jiping Wang Martin Pomerantz 《Journal of Polymer Science.Polymer Physics》1994,32(14):2395-2404
Optical absorption and photo-luminescence measurements were performed on a series of semiconducting polymers, based upon phenylene linkages, that have discrete emitter units. In these polymers, broken conjugation has been achieved in two ways: by introducing metalinkages between various numbers of para-connected aromatic groups or by severe steric distortion of a fully conjugated main chain. In either case, electronic states are localized on relatively small units, resulting in a large (π, π*) band gap. The band gap decreases with increasing emitter unit conjugation, as expected. Blue light emission was observed from these materials, with the peak emission wavelength red shifted (by greater than 1 eV on average) from the peak absorption. © 1994 John Wiley & Sons, Inc. 相似文献
85.
86.
M. A. Reynolds 《Semigroup Forum》1984,30(1):291-296
87.
S W Pelletier N Adityachaudhury M Tomaz J J Reynolds R Mechoulam 《The Journal of organic chemistry》1965,30(12):4234-4247
88.
Spectrophotometric studies of the copper-glycerol complex are reported. A single 1 : l complex is formed under the experimental conditions employed. The interference of precipitated or colloidal copper(II) hydroxide can be overcome by filtration through glass-fibre discs or by application of a correction factor. Filtered solutions of the complex in 90% ethanol obey Beer's law over a wide range of concentration. The stability of the complex and the effects of variation in alcohol and alkali concentration have been studied.An absorptiometric method for the determination of 0.5–40 mg of glycerol is proposed and the effect of possible interferences is considered. 相似文献
89.
Further studies on the polarography of trivalent chromium in concentrated calcium chloride solution are described. Details are given of a chloride-hydroxylamine base electrolyte (7.4M with respect to chloride) in which chromium may be determined directly in the presence of nickel. This method is not applicable if the nickel-chromium ratio is large. Results are presented and certain theoretical aspects are discussed. 相似文献
90.
Alan Reynolds 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1961,12(2):149-158
Zusammenfassung Die Wirbelströmung in einer turbulenten kompressiblen Flüssigkeit wird behandelt. Die Bewegungsgleichungen werden durch die Vernachlässigung der kleineren Glieder vereinfacht. Die experimentellen Ergebnisse erlauben eine Fehlerrechnung für einen Fall. Ein wichtiger Schritt in der Vereinfachung ist die Voraussetzung, dass die Radialgradienten viel grösser sind als die Axialgradienten. Für die kräftigen Wirbel erwies sich diese Annahme sowohl durch die Erfahrung als auch aus den wesentlichen theoretischen Betrachtungen heraus als begründet. Die vereinfachten Gleichungen zeigen einige wichtige Aspekte der schnelldrehenden Strömungen und geben einen Anhaltspunkt für die ausführlicheren Studien.
Notation r radial co-ordinate - z axial co-ordinate - u, U, u radial velocity component, its time-mean value, and the turbulent perturbation to it - v, V, v tangential or swirl velocity component, etc. - w, W, w axial velocity component, etc. - p, P, p fluid pressure, etc. - ,R, fluid density, etc. - , , , numbers small with respect to unity - C, F, G, G 0 constants of integration 相似文献
Notation r radial co-ordinate - z axial co-ordinate - u, U, u radial velocity component, its time-mean value, and the turbulent perturbation to it - v, V, v tangential or swirl velocity component, etc. - w, W, w axial velocity component, etc. - p, P, p fluid pressure, etc. - ,R, fluid density, etc. - , , , numbers small with respect to unity - C, F, G, G 0 constants of integration 相似文献