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21.
Thomas Amend Hans-Dieter Belitz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1989,189(2):103-109
Summary Wheat flour particles sprinkled on a water surface form strands which are visible in the light microscope. These strands form aggregates by means of mechanical forces which show viscoelastic behaviour. Amino acid analysis of both the protein strands and the aggregates formed shows that they consist of gluten protein. The formation of the protein strands occurs at the air/water interface and results from the action of a protein film which spreads around the flour particles.
Mikroskopische Untersuchungen von Mehl/Wasser-Systemen
Zusammenfassung Weizenmehlpartikel, die auf Wasser gestreut werden, bilden lichtmikroskopisch sichtbare Stränge aus. Durch mechanische Beanspruchung lassen sich these Stränge zu Aggregaten zusammenfassen, die visco-elastisches Verhalten zeigen. Die Aminosäureanalyse sowohl der Proteinstrange wie auch der daraus gebildeten Aggregate zeigt, daß es sich dabei um Kleberprotein handelt. Die Proteinfäden entstehen an der Wasser-Luft-Grenzflache als Folge eines spreitenden Proteinfilms, der sich um die Mehlpartikel herum ausbreitet.相似文献
22.
Dr. G. Pönisch 《Computing》1987,39(1):1-17
A direct method is described for computing a hysteresis point (double turning point) corresponding to a cusp point of a system ofn nonlinear equations inn variables depending on two parameters. By addition of two equations a minimally extended system ofn+2 nonlinear equations is constructed for which the hysteresis point is an isolated solution. An efficient implementation of Newton's method is presented not requiring evaluations of second derivatives of the original problem. Two numerical examples show the efficiency of theQ-quadratically convergent method. 相似文献
23.
Dr. jur. Thomas Sassenberg Assessor Niclas Bamberg 《Datenschutz und Datensicherheit - DuD》2006,30(4):226-229
Ob Betriebsvereinbarungen im Sinne des § 4 Abs. 1 BDSG eine „andere Rechtsvorschrift” sind und damit die Regelungen des BDSG
einschr?nken dürfen, geh?rt zu den Standardfragen des praktischen Arbeitnehmerdatenschutzes. Die Autoren befürworten eine
weite betriebliche Regelungskompetenz, beschr?nken diese aber zum Schutz der Arbeitnehmer durch eine Reihe datenschutzrechtlicher
Mindestanforderungen, die Betriebsvereinbarungen einzuhalten haben. 相似文献
24.
Brian M. Louie Thomas Franaszek Tina Pho Wen Yen Chiu David S. Soong 《应用聚合物科学杂志》1985,30(9):3841-3856
Oxygen injection has been proposed and experimentally demonstrated as an effective control measure for limiting the rate of heat release and altering the rate of polymerization in emulsion processes. A detailed mathematical model has been previously developed to describe the system behavior with and without oxygen injection. A simple lab scale apparatus was constructed and run extensively. Only trace quantities of oxygen are needed to inhibit the reaction completely. The facile response makes this method attractive for fast temperature control. However, because of the rapid penetration of dissolved oxygen into the polymer particles, growing radical chains are terminated prematurely, lowering product molecular weights. To minimize this detrimental effect, pulsed oxygen control is used and extensive experimental work was performed to determine the effects of controller set points on molecular weight. Moderate oxygen flows and moderate set point temperatures are found to give the optimal response without significant lowering of the final molecular weight. Injected quantities agree well with the order-of-magnitude sparging calculations needed to completely stop initiation. However, complete agreement between model simulations and experimental results was not reached due to an unmeasured loss of monomer from the reactor. Chain transfer to monomer is found to be important in modeling the polymer molecular weight. It has, however, a negligible effect on the reaction rate. 相似文献
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28.
Dr. D. L. Clements 《Acta Mechanica》1985,56(1-2):31-40
Summary An examination of possible forms of traction free surface wave in anisotropic elastic materials is undertaken. The results yield some interesting features of a certain arbitrariness which exists in displacement waves on a traction free surface in anisotropic media. 相似文献
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30.
V. Thomas Paul S. Saroja P. Hariharan A. Rajadurai M. Vijayalakshmi 《Journal of Materials Science》2007,42(14):5700-5713
This paper presents the results of a study on the microstructural and microchemical variations in a multipass Gas Tungsten
Arc weld (GTAW) of modified 9Cr-1Mo steel. The changes brought about in the steel due to the heating and cooling cycles during
welding and the subsequent effects due to reheating effects during multipass welding are described. Detailed analytical transmission
electron microscopy has been carried to study the type and composition of the primary and secondary phases in this steel.
The systematic changes in microstructural parameters such as Prior Austenite Grain Size, martensite lath size, number density,
size and microchemistry of carbides, have been understood based on the different transformations that the steel undergoes
during the heating and cooling process. Based on the observed microstructure, an attempt has been made to identify distinct
microstructural zones and possible thermal cycles experienced by different regions of the weldment. 相似文献