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81.
Dr.-Ing. Wilhelm Spruth 《Electrical Engineering (Archiv fur Elektrotechnik)》1958,43(7):427-449
Ohne ZusammenfassungMit 47 AbbildungenDie vorliegende Arbeit ist ein Auszug aus der Dissertation des Verfassers (Technische Hochschule Aachen 1956/57). 相似文献
82.
K Fischer V Lutz O Wilhelm M Schmitt H Graeff P Heiss T Nishiguchi N Harbeck H Kessler T Luther V Magdolen U Reuning 《Canadian Metallurgical Quarterly》1998,438(1-2):101-105
It has been well established that the cytoskeleton is an essential modulator of cell morphology and motility, intracytoplasmic transport and mitosis, however cytoskeletal linkage to the organelles has not been unequivocally demonstrated. Indeed, cytoskeleton appears to be essential in determining and modulating gene phenotype as a function of cellular environment. According to recent studies, the organization of the cytoskeleton network together with associated protein(s) could be essential in regulating mitochondrial function and particularly the permeability of the mitochondrial outer membrane to ADP. The aim of this chapter is to summarize the main properties of the cytoskeletal environment of mitochondria and the possible role(s) of this network in mitochondrial function in myocytes. 相似文献
83.
84.
Distraction-lengthening technique is quite useful in a variety of congenital hand deformities with hypoplastic, or primary normal but secondary shortened (constriction ring syndrome) finger rays. It appears that around the age of two years is the earliest practical time to start distraction; certainly distraction and secondary surgical procedures to improve function should be completed before school entry age whenever possible. Between June 1990 and March 1993, nine distraction lengthening procedures (5 thumbs, 1 index, 3 little fingers) in five patients presenting with congenital hand deformities, were carried out. Although restoring length to the finger, lengthening does not provide normal circumference or, of course, interphalangeal joint motion. Amelioration in function seems to be more important than the esthetic gain. Distraction lengthening tolerates only few errors of indication, operative technique, and/or postoperative management. A high compliance of the patient and her/his parents as well as a close follow-up by an experienced surgeon, are mandatory for a good result. A variety of possible complications have been described. Generally, complication risk increases in cases of simultaneous and multiple level lengthening. Provided adequate operative technique and postoperative care, superficial pin infection and fracture in the region of distraction are the major complications. Contrary to adults, sufficient bone formation by distraction is the rule in children. Therefore, the distraction-lengthening technique is preferred to the distraction-interposition technique in the treatment of congenital hand deformities. The latter should only be used as a salvage procedure in the rare cases of insufficient callus formation. Because of the missing growth potential and reduced joint mobility, distraction lengthening is the therapy of second choice when compared to microvascular second toe transplantation. 相似文献
85.
Beschreibung der Versuchsapparatur zur Messung der Thermospannung der Kette Rh |T + Δ AIN |T Rh für Temperatur-differenzen bis zu ± 60 °C zwischen 1350 und 1650 °C. Ermittlung der Thermokraft und ihres homogenen Anteils. Berechnung der Überführungswärme der wandernden Ionen aus der homogenen Thermokraft. Erörterung zum Leitungsmechanismus im Aluminiumnitrid AlN. 相似文献
86.
Wilhelm Wiederholt 《工业材料与腐蚀》1971,22(11):909-915
Corrosion research by Bundesanstalt für Materialprüfung (BAM) in Berlin A memorial review on the occasion of its 100th anniversary The report deals with the develop-ment in the field of corrosion, from the turn of the century to the present day. About 1900 scarcely anybody spoke of corrosion and corrosion protection. Start-ing from this zero point the whole field with its tremendous economic impor-tance has gone through an ever faster evolution. The knowledge concerning the origins of corrosion has been steadily increasing and well-founded. The corro-sion theories could be supported by practical experience and increasing scien-tific knowledge. On the strength of the knowledge on corrosion and the me-chanism of corrosion processes it became possible to develop efficient corrosion protection procedures. lnstitutions such as Materialprüfungsamt, Berlin-Dahlem, Chemisch-Technische Reichsanstalt and Bundesanstalt für Materialprüfung have had an important part in these succes-ses. It can be considered to be a parti-cular recognition of the achievements and merits of the predecessors of the present BAM, that after the merger of the two branches -i. e. materials test-ing and corrosion research -the latter bas been receiving particular attention and efficient support. 相似文献
87.
Guenter Ahlers 《Journal of Low Temperature Physics》1969,1(6):609-631
In this paper available measurements of the attenuation and dispersion of first sound near the superfluid transition in He4 are re-examined. Particular attention is given to the effect of the gravitational inhomogeneity upon the measurements, and the thermodynamic velocity is used to obtain the dispersion contribution from measured velocities at nonzero frequencies. The re-interpreted results are discussed in terms of current theories. Although there is partial agreement between experiment and theory, a number of aspects of the problem requires further theoretical and experimental investigation. 相似文献
88.
Wilhelm Heitland 《Forschung im Ingenieurwesen》1981,47(5):165-167
Ohne Zusammenfassung
ProfessorWilhelm Heitland, Fachhochschule Bielefeld FBR 3 (Maschinenbau). Lehrgebiet Mathematik. 相似文献
89.
Ralf?Buscherm?hleEmail author Mark?Br?rkens Ingo?Brückner Werner?Damm Wilhelm?Hasselbring Bernhard?Josko Christoph?Schulte Thomas?Wolf 《Informatik-Spektrum》2004,27(2):146-158
Die Gewährleistung der korrekten
Funktionsweise von Hard- und Software ist ein entscheidender
Faktor bei der heutigen Systementwicklung. Dies trifft ganz
besonders auf das Gebiet der sog. sicherheitskritischen
Systeme zu, bei dem ein Systemversagen Menschenleben gefährden
kann. 相似文献
90.
Entwicklung verschiedener Kalorimeteranordnungen zur Bestimmung des Wärmeinhalts zwischen 0 und 25, 25 und 65, 25 und 1400 und zwischen 25 und 1720 °C. Die mittlere und wahre spezifische Wärme von Schmelzkalk (Kristallkalk). Vergleich der Ergebnisse mit Angaben des Schrifttums über gebrannten Kalk. 相似文献