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41.
Three hypoeutectic Fe containing Al–Si–Mg alloys for casting crash relevant automotive components are experimentally investigated. The comparatively short heat treatments include solutionising at 540°C for 5 min or at 465°C for 60 min respectively, compressed air quenching and artificial aging at 223°C for 120 min. Characteristic mechanical parameters are determined by tensile, plate bending and Charpy pendulum impact tests. Intermetallic phases are identified by scanning electron and by light microscopy. The results show that increasing the Mg content promotes the precipitation of Mg2Si particles, which enhance the strength. Increasing the Fe content promotes the formation of intermetallic Fe bearing particles which reduce the energy absorption capacity and the ductility. Increasing the Si content has the similar effect, since the volume fraction of the eutectic phase and the size of the intermetallic particles increase.  相似文献   
42.
    
The mutant Saccharomyces cerevisiae ATCC 36858 was used in the production of ethanol and/or fructose from synthetic media in batch processes with raffinose, melibiose or sucrose. The mutant was able to hydrolyze all the sugars used and to selectively ferment glucose and galactose to ethanol while fructose accumulated in the fermentation medium. The fructose yield was above 89% of the theoretical value in the media with either raffinose or sucrose, when initial concentrations were between 131.5 g dm?3 and 242.0 g dm?3. The ethanol yields were 82% and 77% of the theoretical values in the media with melibiose and sucrose, respectively, and about 72% of the theoretical value when raffinose was used. The fructose fraction in the carbohydrate content of the produced syrups was more than 96% when raffinose concentration was below 189.1 g dm?3. However, even at a sucrose concentration of 187.9 g dm?3, the produced syrup contained 100% fructose. Some oligosaccharides were also produced in all tested media. The produced oligosaccharides were consumed by the end of the fermentation process. These findings can be useful in the production of ethanol and high fructose syrups using raw materials based on sucrose and raffinose such as molasses. Copyright © 2003 Society of Chemical Industry  相似文献   
43.
Bozorgi  S. Amir  Orouji  Ali A.  Abbasi  Abdollah 《SILICON》2022,14(11):5905-5912
Silicon - In this paper, a SOI MOSFET is proposed using a P-N structure and an electrically hole-free region (EHFR-SOI). In this structure, to improve the electrical characteristics such as short...  相似文献   
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