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71.
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Konrad Grob Angelo Maria Giuffr Ugo Leuzzi Biagio Mincione 《European Journal of Lipid Science and Technology》1994,96(8):286-290
Recognition of adulteration by other oils via direct analysis of the minor components (“sterol fraction”) is shown for olive oil. 10 % of various oils were admixed, the free alcohols silylated and the minor components analyzed by on-line coupled LC-GC-FID. For most oils, even smaller additions can be recognized. Admixed oils can no longer be determined, however, if their minor components have been removed by strong raffination. Bleaching of rapeseed oil with 7% of earth at 180 °C, in fact, completely removed free and esterified sterols. 相似文献
73.
Ohne Zusammenfassung 相似文献
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Hawke R.S. Susoeff A.R. Asay J.R. Ang J.A. Hall C.A. Konrad C.H. Wellman G.W. Hickman R.J. Heath W.A. Martinez J.R. Sauve J.L. Vasey A.R. Shahinpoor M. 《IEEE transactions on magnetics》1991,27(1):28-32
Results obtained with the HELEOS (hypervelocity experimental launcher for equation of state) railgun, which uses a two-stage light-gas gun (2SLGG) as an injector, are presented. The high-velocity 2SLGG injector preaccelerates projectiles up to ~7 km/s. The high injection velocity reduces the exposure duration of the railgun barrel to the passing high temperature plasma armature, thereby reducing the ablation and subsequent armature growth. The 2SLGG also provides a column of cool, high-pressure hydrogen gas to insulate the rails behind the projectile, thereby eliminating restrike. A means to form an armature behind the injected projectile has been developed. In preliminary tests, the third-stage railgun has successfully increased the projectile velocity by 1.35 km/s. Extensive diagnostics have been used to determine the behavior of the armature and track the launcher's performance. Insome cases, velocity increases in the railgun section have been achieved, which are in close agreement with theoretical predictions, whereas in other experiments deviations from theoretical have been observed. The reasons for and implications of these results are addressed. Recent tests are reported 相似文献
77.
Karl Heinz Schwalbe 《Engineering Fracture Mechanics》1993,45(6):751-758
The Engineering Treatment Model (ETM) provides a means for estimating the load line displacement of a cracked body. Under contained yielding conditions the model uses available linear elastic solutions with an Irwin-type plasticity correction of the crack length. The magnification factor (F/Fy)1/n describing the material's strain hardening behaviour is applied for extrapolation into the regime of net section yielding. Comparison of ETM estimates with finite element and experimental results shows that the assumptions of the model are realistic. 相似文献
78.
Vocabularies that provide unique identifiers for conceptual elements of a domain can improve precision and recall in knowledge-management applications. Although creating and maintaining such vocabularies is generally hard, wiki users easily manage to develop comprehensive, informal definitions of terms, each one identified by a URI. Here, the authors show that the URIs of Wikipedia entries are reliable identifiers for conceptual entities. They also demonstrate how Wikipedia entries can be used for annotating Web resources and knowledge assets and give precise estimates of the amount of Wikipedia URIs in terms of the popular Proton ontology's top-level concepts. 相似文献
79.
Anna Artho Konrad Grob Carlo Mariani 《European Journal of Lipid Science and Technology》1993,95(5):176-180
The previous on-line LC-GC method for the direct analysis of the minor components in oils and fats (without cleavage of esters) was modified: The free alcohols/sterols were silylated instead of acylated, and the LC fraction transferred to GC is widened to range from the beginning of the LC chromatogram up to the sterol esters. Silylation eliminated the problem that acylation may esterify some free alcohols with free fatty acids from the oil if the oil or fat is of high acidity. Widening of the LC fraction to include squalene and the tocopherols added information to that previously obtained. 相似文献
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