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11.
The operation principle of the mass-controlled capillary viscometer is presented for a Newtonian liquid. The derived equation for the temporal changes of the mass in a liquid column draining under gravity through a discharge capillary tube accounts self-consistently for the inertial convective term associated with the acceleration effect. The viscosity of water measured at different temperatures using the new approach is in good agreement with literature data. 相似文献
12.
Al/Cu/Al and Cu/Al/Cu triple layers with approximately 10 nm single layer thickness deposited on tungsten substrates were analyzed in the early stages of reactive interdiffusion by means of atom probe tomography. The first reaction product is found after 5 min thermal treatment at 110 degrees C and identified by direct chemical analysis to be Al2Cu. Surprisingly, we found a significant asymmetry in the reaction rate of the new phase with the stacking sequence: the thickness of the product grown at the interfaces, at which Cu is deposited on top of the Al layer, is approximately 1.5-2 times thicker than the other one at the interfaces at which Al is deposited onto a Cu layer. On the other hand, at both interfaces the thickness of the product layer depends parabolically on time. No precursory interdiffusion and no distinct nucleation process of the product are observed. 相似文献
13.
Peter Gottesmann und Reiner Hamm 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1984,178(5):366-370
Zusammenfassung Veränderungen in der subcellulären Verteilung der Mitochondrien-Enzyme Lipoamiddehydrogenase (LIPDH), Citratsynthase (CS) und -Hydroxyacyl-CoA-dehydrogenase (HADH) im Muskelgewebe lassen Aufschlüsse über Art und Ausmaß von Schädigungen der Muskelmitochondrien während der Lagerung und Behandlung von Fleisch erwarten und können möglicherweise als Grundlage für Methoden zur Unterscheidung zwischen Frischfleisch und aufgetautem Gefrierfleisch dienen. — Es werden Standardverfahren zur Bestimmung der Aktivität von LIPDH, CS und HADH in Gewebeextrakten und Muskelpreßsaft beschrieben. Der Einfluß von Enzymkonzentration, pH-Wert und Temperatur auf die Enzymaktivitäten im Muskelextrakt wurde untersucht. Ferner wurden die Streubreiten der mit den Standard-methoden gemessenen Enzymaktivitäten ermittelt.
Diese Arbeit ist Teil einer Dissertation von P. Gottesmann (Technische Universität München, 1982); sie wurde durch Mittel des Bundesministeriums für Jugend, Familie und Gesundheit unterstützt 相似文献
Lipoamide dehydrogenase, citrate synthase, and-hydroxyacyl-coenzyme A-dehydrogenase of skeletal muscleI. Studies on the determination of activities in tissue extracts
Summary It is to be expected that changes in the subcellular distribution of the mitochondrial enzymes lipoamide dehydrogenase (LIPDH), citrate synthase (CS) and -Hdroxyacyl-CoA-dehydrogenase (HADH) in the muscle tissue give information on the type and the extent of damage of mitochondria during storage and treatment of meats; such changes may be also used as basis of methods for the differentiation between fresh and frozen/thawed meat. — Standard methods for the determination of the activities of LIPDH, CS, and HADH in tissue extract and muscle press juice are described. The influence of enzyme concentration, pH and temperature on the enzyme activities in muscle extract was investigated. Furthermore the error in the enzyme analyses by the standard methods was determined.
Diese Arbeit ist Teil einer Dissertation von P. Gottesmann (Technische Universität München, 1982); sie wurde durch Mittel des Bundesministeriums für Jugend, Familie und Gesundheit unterstützt 相似文献
14.
Angelika Görg Wilhelm Postel Reiner Westermeier 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1982,174(4):282-285
Summary Horizontal SDS electrophoresis of 18 legume seed protein extracts was performed in ultrathin-layer polyacrylamide gels on foil supports. Separation results of the SD S pore gradient electrophoresis (T=4–22.5%) are compared to those of SDS electrophoresis in a constant pore size gel (T=10%). Resolution as well as the sensitivity (0.1 g protein per band) of the ultrathin-layer SDS pore-gradient electrophoresis were extremely high. Because of the very low gel thickness, separation, staining and drying were completed in substantially shorter times than achieved with conventional thick gels. An easy technique for casting ultrathin-layer (360 gm) concave gradient gels for 10 cm separation distance and a width of 25 cm is described. The even distribution of the concave exponential pore-gradient over the whole gel width is demonstrated. Molecular weights of the legume proteins are detected from 5,000 to 110,000 daltons. The protein patterns are genus- and species-specific.
Horizontale Ultradünnschicht SDS-Gradientengel-Elektrophorese von Leguminosensamenproteinen
Zusammenfassung Die ausgezeichnete Trennschärfe der horizontalen Ultradünnschicht-SDS-Gradienten-gel Elektrophorese wird am Beispiel von Samenproteinen 18 verschiedener Leguminosengattungen, -arten und -sorten gezeigt. Es werden die Trennergebnisse der SDS-Elektrophorese mit Gelgradienten (T=4-22,5%) bzw. mit Gelen konstanter Porengröße (T=10%) verglichen. Das höchste Auslösungsvermögen und die beste Trennschärfe zeigen ultradünne Gradientengele. Die Nachweisempfindlichkeit ist bei allen Ultradünn-schicht-SDS-Elektrophoresen sehr hoch (0,1 g Protein/Bande). Da die auf Folie polymerisierten Gele sehr dünn sind (360 m) kann mit wesentlich verkürzten Trenn-, Färbe-, Entfärbe- und Trocknungszeiten gear-beitet werden. Es wird eine einfache Herstellung ultradünner Polyacrylamidgele mit exponentiellen konkaven Gradienten für die Trenndistanz von 10 cm mit einer Breite von 25 cm beschrieben. Die gerade und gleichmäßige Verteilung des Gradienten über die gesamte Gelbreite wird gezeigt. Mit der beschriebenen Methode werden bei den untersuchten Leguminosen-proteinen Molekulargewichte von 5 000 his 110 000 Dalton gefunden. Die Proteinmuster erweisen sich als gattungs- und artspezifisch.相似文献
15.
The scope of the article is to describe the automated production of a thixoformed steel part. The production plant was set up within a prototype initiative at the Institute of Metal Forming in cooperation with the Institute of Automatic Control of RWTH Aachen University and industrial partners. Preliminary experiments showed that the quality of the formed parts varied to a great extent due to changing production conditions since the handling of the billet was carried out manually. To eliminate the possible disturbances introduced by the manual handling of the billet, an automation concept has been elaborated in order to guarantee a defined production environment. An industrial robot (KUKA) fulfils the handling tasks like the feeding of the induction coil with the feedstock material and the placing of the heated billet into the hydraulic press. The removal of the formed part from the press is realised by a simple mechanical device in order to be able to use only one gripper. The design of the gripper ensures a minimal heat loss during handling. The induction coil, the gripper system and the cavity are flooded with inert gas in order to prevent scaling. The sequence control for the production of a part is realised on the controller of the robot which provides sufficient PLC functionality and can be easily equipped with the required I/O components to trigger the different automation components. 相似文献
16.
Reiner M. W. Reising Bahram M. Shahrooz Victor J. Hunt Andy R. Neumann Arthur J. Helmicki 《Canadian Metallurgical Quarterly》2004,8(3):265-274
In an effort to assess the constructability and performance of bridges with fiber-reinforced polymer (FRP) composite decks, the short-term and long-term responses of a 207 m, five-span bridge retrofitted with four different FRP panel systems were monitored. The overall aspects of the panel systems, connection details, and construction techniques are presented prior to presentation of the observed and measured responses. Key design parameters (impact factors, girder distribution factors, and level of composite action) for FRP and reinforced concrete decks are evaluated. This paper demonstrates that FRP replacement decks are a viable alternative to reinforced concrete decks and identifies the differences in performances of various FRP deck systems. Two of the FRP panel systems were found to perform considerably better than the other deck systems. Issues that may reduce the service life of FRP deck systems are presented and discussed. 相似文献
17.
18.
Abstract Error-diffused quantization has been applied to the generation of cell-oriented computer-generated Fourier transform holograms, resulting in reduced reconstruction errors. Improvements are demonstrated when applied to the algorithms of Lohmann, Lee and Burckhardt after invoking realistic constraints on the minimum size of the printable spot for an electrophotographic laser printer. 相似文献
19.
Prof. Dr. Reiner Doluschitz Dr. sc. Agr Barbara Engler Christa Hoffmann Dipl.-Ing. Agr. 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2010,68(1):11-19
Based on the information needs of stakeholders (from animal feed to consumers, including the authorities and organizations
involved) an integrated IT-system without structural fractures and barriers shall be developed. It will be designed to enable
the merging, internal exchange and utilization of relevant data and parameters. Subprojects of the interdisciplinary research
consortium cover the entire supply chain and also address cross-section issues, such as logistics, costs and benefits, veterinarian
services, quality assurance systems, a comprehensive IT-solution including data format standards (agroXML), and requirements
for sustainability. Substantial added value has been generated from intensive interdisciplinary co-operation. The interdisciplinary
research project IT FoodTrace () aims at achieving traceability and quality assurance along the food chain of “meat and meat products”. The aim of this paper
is the presentation of (a) the complexity of underlying problems, (b) the project structure, (c) available results from selected
sub-projects and (d) the added values from interdisciplinary co-operation. Selected findings include an optimized single animal
data collection and information management in livestock systems, benefits gained by linking animal-health-related information
to an integrated animal-health system, requirements and features of an integrated IT-System, including consequences for data
protection and security, and findings from a Delphi-based cost–benefit-analysis of an integrated quality assurance and traceability
system. 相似文献
20.