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971.
V. M. Blinov I. V. Doronin A. E. Antoschenkov Yu. A. Lukina 《Russian Metallurgy (Metally)》2007,(2):140-142
The effect of anomalous structural constituents in ShKh15 steel on its technological ductility during cold deformation has been studied. Additional high tempering of hot-rolled billets subjected to spheroidizing annealing is shown to remove retained lamellar pearlite and needle carbides, increasing the technological ductility of this ball-bearing steel. 相似文献
972.
Heritabilities were estimated for lactation average log, base 2, somatic cell count from cows with four or more tests in each lactation. Estimates were for first, second, and third or later parities (defined by age at calving) individually and for mixed parities. Estimates were from sire components of variance with numbers of sires and daughters of 406 and 22,140; 337 and 8,659; 311 and 6,122; and 310 and 10,217 for mixed, first, second, and third or later parities, respectively.Both sire and error components of variance increased with parity. Heritabilities were .18, .09, .10, and .29, for mixed, first, second, and third or later parities. 相似文献
973.
Accurate assessment of the availability of solar energy at the Earth's surface is hampered by difficulties associated with the variability of solar radiation in space and time and with the angular position in the sky hemisphere. This paper assesses each of these problem areas by highlighting the difficulties and the attempts to offset them. Major emphasis is placed on extrapolation and interpolation procedures, the sensitivity of inclined surfaces to variations in the solar input, numerical models for calculating the irradiance of inclined surfaces and the time scales for which these computations are valid.Finally, the reader is urged to consider the significance of these difficulties in light of both radiation measurement errors and the sensitivity of the application to imprecise determinations of the radiation environment. 相似文献
974.
E. Gehri 《Holz als Roh- und Werkstoff》1985,43(3):83-88
Zusammenfassung Generell stellen die Verbindungsbereiche Schwachstellen dar. Zwar k?nnen in gewissen F?llen derartige Schwachstellen umgangen
werden. im Vordergrund steht jedoch eine gesicherte Erh?hung der Leistung bekannter Verbindungsarten. Voraussetzung hierfür
sind auf die jeweilige Verbindung (und Holzart) ausgerichtete konstruktive L?sungen. H?ufig lassen sich derartige Entwicklungen
nicht oder nur unvollst?ndig durch bereits normierte Regeln der Baukunde abdecken.
In general jointed areas are considered weak links. Although in certain cases these weak areas may be circumvented, it is
important to make efforts towards improving the performance of established joints. Constructive solutions adapted to specific
joints (and wood species) are one of the preconditions towards this am. Frequently this kind of development is merely insufficiently
or not at all covered by existing standardized regulations in construction technology.
Nach einem Vortrag des Verfassers auf der Dreil?nder-Holztagung 1984 in Augsburg 相似文献
High performance jointing techniques—State of art and development
Nach einem Vortrag des Verfassers auf der Dreil?nder-Holztagung 1984 in Augsburg 相似文献
975.
976.
S. K. SASTRY F. D. McCAFFERTY E. G. MURAKAMI G. D. KUHN 《Journal of food science》1985,50(5):1501-1502
Dry red kidney beans were canned using two different pretreatments: soaking for 12 hr at 20°C, and vacuum hydration for 5 min followed by soaking for 2 hr at temperatures from 45-59.1°C. Samples were then packed, processed to commercial sterility, and tested for percentage of split beans after processing. Vacuum hydration pretreatments greatly decreased the incidence and severity of splitting in the canned product and accelerated water uptake while retaining the same moisture content after soaking as the conventional soak treatment. Vacuum-hydrated beans gained less moisture during retorting than conventionally treated samples. 相似文献
977.
We have performed tribotechnical tests of carbonaceous filled polytetrafluoroethylene in a wide range of loads with the recording of acoustic emission signals. Based on a spectral analysis of the sequence of rms deviations of acoustic emission signals using a discrete Fourier transform, we have constructed a normalized energy spectrum. We show that the mass wear of the material can be determined from the power of the high-frequency component of the spectrum obtained. 相似文献
978.
979.
The solution of several electrostatic potential problems involving open spherical perfectly conducting shells is presented in the context of the dual series equations method. These equations are a consequence of mixed boundary conditions imposed on the electric potential and field. A solution is given for the dual series equations corresponding to two concentric spherical shells, one of which has a circular aperture. The aperture dipole moment, the capacity, and field penetration of some electrostatic devices are also calculated. 相似文献
980.