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81.
作为战略因素的包装工业 近年来,整个包装工业的地位突然有了巨大的提高,尤其是在亚洲,如中国. 相似文献
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A method for solving cylindrical electromagnetic boundary-value problems is presented. The method is semidiscrete. The wave equation is written in cylindrical coordinates and a differential-discretizing process is used in angular direction, and in the radial direction the analytic solutions are used. The new method is called the method of angular lines (MAL). To confirm the validity of MAL Dirichlet- and Neumann-type boundary-value problems of a two-dimensional scalar wave equation are investigated. The results show good agreement with previously published results. Advantages and disadvantages of the method are discussed. © 1995 John Wiley & Sons, Inc. 相似文献
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Children, young people and women at the age of possible maternity form the majority of patients operated by extracorporal circulation. A longterm planning of these operations should also have donor in call, who are compatible with the patients' Rh groups and Kell antigens. Having practiced such a selection of donors we succeeded in reducing the formation of immune antibodies. 6 out of 330 patients had antibodies, but 4 had been sensibilized before operation. In the case of the other 2 it would not be excluded that they might have been immunized a long time ago. We emphasize the importance of hemodilution, strict indication of every postoperative therapy with red cells and the autologous transfusion. 相似文献
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Current oscillations occurring in the positive differential resistance region of the d.c. I–V characteristics of Au-compensated n-type silicon pin diodes have been investigated. The experimental results strongly suggest that the current oscillations are caused by the formation of unstable filaments prior to the occurrence of stable filaments which are connected with the negative differential resistance region typical for double injection diodes with deep levels. On the basis of this model the degree of modulation could be increased up to 30% in our diodes. 相似文献
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Untersuchungen über das Rekristallisationsverhalten von Stahldrähten aus den Stahlsorten St 37, C 35, C 70, D 12-2, D 15-2, D 35-2 nach Verformungsgraden von 10 bis 50% bei unterschiedlichen Rekristallisationsbedingungen mit Aufheizgeschwindigkeiten zwischen 6 und 350 °C/s, Glühtemperaturen zwischen 300 und 700 °C und einer Haltedauer zwischen 60 und 1000 s. Beschreibung der Induktiverwärmungsanlage. Ermittlung der Festigkeitskennwerte wie Zugfestigkeit, Streckgrenze, Bruchdehnung, Brucheinschnürung sowie des Gefüges und der Korngröße nach den verschiedenen Glühungen. 相似文献
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In trial 1, eight Holstein heifers weighing 410 kg were used in an 8 x 8 Latin square and fed TMR containing 79.3% alfalfa silage and 20% soybeans. The first four treatments were raw soybeans, soybeans roasted and held for 3 h at the roasting temperature, extruded soybeans, and soybeans roasted in a California Pellet Mill Jet-Sploder. The remaining four treatments were obtained by altering the residence time of soybeans in the Jet Sploder. The temperatures of soybeans exiting the roaster were 117, 126, 138, and 154 degrees C for the last four treatments. The soybeans held 3 h postroasting and the extruded soybeans resulted in the highest estimate of postruminal available lysine. Blood plasma concentrations of essential and branched-chain AA were highest in heifers fed soybeans held 3 h postroasting. In trial 2, 44 Holstein heifers weighing 150 to 250 kg were assigned randomly to one of four TMR. Diets consisted of 91.8% alfalfa silage and 7.5% of one of four soybean treatments. Treatments were raw soybeans, soybeans roasted in a drum roaster with an exit temperature of 146 degrees C, and those roasted with exit temperatures of 141 or 146 degrees C and held for .5 h. Estimated postruminal available lysine was higher for soybeans roasted and held versus roasted or raw soybeans. However, BW gain for heifers was similar across diets, averaging .90 kg/d for 12 wk. Concentrations of AA in plasma were not affected by diet. Overall, results support the recommendation of holding soybeans for at least .5 h following roasting. 相似文献
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