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201.
Analytische Möglichkeiten einer neuen Gerätegeneration. Weiterentwicklung des Verfahrens mit synthetischer Eichung bis zur Bestimmungsgrenze 2 μg/g. 相似文献
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Pipe fabrication for the repair sector. The paper discusses the changes in pipe fabrication that have taken place in recent years. These enable repair work to be carried out more efficiently, without thereby impairing the flexibility and speed of operation that are essential to maintenance work. A prerequisite for this is that work on the pipes be transferred to workshops. Only here is it possible for manual operations, such as manual welding, to be reduced to a minimum and be replaced by mechanized or semi-mechanized welding methods. The use of modern machines for bending the pipes is more economic than the welding in of pipe bends. Necking out of the pipes by mechanical means or the use of mechanically pre-fabricated connections permit optimum preparation of the weld seam for branch fittings. Any additional work on the pipes, where this is necessary, is carried out at workplaces specially designed for the purpose. 相似文献
205.
Albert Kochendoerfer Kunihiko Kobayashi Horst Dieter Schulze Karl Edgar Hagedorn Ulrich Ruediger 《Engineering Fracture Mechanics》1976,8(4):737-741
The flow and fracture stresses, σyg and σfg (δ = crack tip displacement), of sharply notched bending specimens of a structural steel U St 37-1 are measured in the temperature range from full scale to small scale yielding. The best adaption of the experimental results for σfg is obtained by a curve which exhibits an intermediate transition, i.e. which follows in a temperature range between an upper, TtM1 and a lower, Ttl1, transition temperature to the curve σyg(T) for the flow stress with a constant δ = δ1. This transition corresponds to that of the slip to the twin nucleated fracture. Two analyses [3,5] according to the local fracture stress, σf*, concept show that the amount and the temperature dependence of σf* are somewhat different for both methods, but that both exhibit an increase of σf* in the transition range. It is concluded that each transition in the nucleation mode of the fracture is connected with such a transition in the fracture stress. It may, however, become indistinct or even be covered by the scatter of the experimental points. 相似文献
206.
Some Practical System Availability Calculations 总被引:1,自引:0,他引:1
The usefulness of a recent result in system availability is displayed and discussed. Methods are presented for solving some problems which arise in the practical implementation of this result. Specifically, equations are provided for calculating the availability of a series system in which one or more components may have a surge or an installed spare. Finally, a manufacturing line efficiency model is described which has system (line) availability as one of its principal factors. 相似文献
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