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11.
R. Bunk U. Leske R. Krompass Z. Pretch K. Rudolf R. Herbig K. Pitch V. A. Tsykanov O. V. Skiba V. A. Makarov L. P. Bol'shakov P. T. Porodnov A. A. Maershin S. S. Keruchen'ko 《Atomic Energy》1989,67(5):802-806
Translated from Atomnaya Énergiya, Vol. 67, No. 5, pp. 320–323, November, 1989. 相似文献
12.
This paper reports on an evaluation of real-time properties of MAP (Manufacturing Automation Protocol) networks by analytical considerations and measurements. Based on a model of the time schedule of a communication cycle figures for response times (transport system) and message delays (MAC layer) are given. The influence of some options for handling acknowledgments within the transport layer is shown. The message delay at MAC layer is separated into an implementation-dependent and a protocol-dependent protion, and an upper bound is derived. Rules for selecting protocol parameters affecting real time behavior are given. Aspects for improved implementations of communication controllers for MAP networks are discussed. 相似文献
13.
The risk of accidents when handling liquid metal and bath, the potential for explosions through reactions of gases, and electrical hazards all highlight the vital importance of safety in the cathode repair and cell restart processes. With respect to hygiene, refractory materials and reaction products must be handled carefully when repairing cathodes and when welding. Personnel therefore require appropriate clothing and protective equipment. This article reviews various procedures—short circuiting a cell, digging out the spent potlining, preparing the empty steel shell, fixing the steel bars to the cathode blocks, and general relining and start-up—in the context of both safety and health. 相似文献
14.
Examined pre- and posttreatment changes in life stressors and social resources and their association with treatment outcomes in a 12-mo follow-up of 424 Ss (aged 18–83 yrs) with unipolar depression. Assessment measures included the Family Environment Scale, Work Environment Scale, and Health and Daily Living Form. As expected, Ss reported significant, multidimensional improvements in their functioning at follow-up. There were modest increases in Ss' social resources but, suprisingly, no overall decrease in stressors. Life stress and resource factors were significantly related to Ss' functioning at follow-up, even after considering the severity of their dysfunction at treatment intake and their length of treatment. Implications for developing a general body of knowledge about the process of recovery and relapse in behavioral disorders are discussed. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
15.
Rudolf E. Greuer 《Fire Safety Journal》1985,9(1):81-87
Physical principles governing mine ventilation systems and state of the art ventilation modeling are initially outlined. Several computer programs for modeling the mine ventilation-mine fire interaction, which were developed during the last decade, are then described. An older program considers fires and ventilation systems as going through a sequence of steady state conditions. Airflow rates, pressure losses, temperatures, fume and methane concentrations can be determined. Newer programs allow transient state fume concentration calculations under the assumption of constant airflow rates as well as the determination of fume exposures of escaping miners. Recent work attempts the complete transient state simulation of fires and all ventilation properties. 相似文献
16.
The conditions for ferrite and pearlite banding in strip and plate made of structural steels were investigated. Factors found to influence the formation of banded structures were the cooling rate during the γ/α-transformation, the former austenite grain size, and the work-hardened condition of the former austenite. Analyses with the aid of an electron beam microprobe made it possible to demonstrate that the carbon-rich bands correspond locally with banded manganese enrichments, yet that they do not form before the course of the γ/α-transformation as a result of secondary segregation. It was possible to explain the mechanism of action of the influencing factors on the basis of this model. 相似文献
17.
The electrochemical copolymerization of furan and thiophene was performed at a constant electrode potential in a binary solvent system consisting of boron trifluoride/ethyl ether and an additional amount of ethyl ether (molar ratio = 1 : 2). The obtained homopolymers and copolymers were characterized with cyclic voltammetry and infrared spectroscopy. The influence of the applied electropolymerization potential and the monomer feed ratio of furan and thiophene on the copolymers was investigated. The furan–thiophene copolymers showed good stability of the redox activity in an acetonitrile‐based electrolyte solution. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
18.
Rudolf Felix 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(2):129-135
Real world applications of a decision model of relationships between goals based on fuzzy relations are presented. In contrast
to other approaches the relationships between decision goals or criteria for each decision situation are represented and calculated
explicitly. The application fields are decision making for financial services and optimization of production sequences in
car manufacturing. 相似文献
19.
Rudolf Kunz 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1906,12(11):641-645
Ohne ZusammenfassungMitteilung aus der K.-k. allgemeinen Untersuchungsanstalt für Lebensmittel in Wien. 相似文献
20.
Michael Kofink Menelaos Papagiannopoulos Rudolf Galensa 《European Food Research and Technology》2007,225(3-4):569-577
The enantiomers of catechin and epicatechin were separated by chiral capillary electrophoresis using modified cyclodextrins
as chiral selectors. Various conditions for the separation system were optimized, including the pH value and the concentration
of the running buffer. A baseline separation of the catechin and epicatechin enantiomers could be achieved by using 0.1 mol l−1 borate buffer (pH 8.5) with 12 mmol l−1 (2-hydroxypropyl)-γ-cyclodextrin as chiral selector, a fused-silica capillary with 40 cm effective length (75 μm I.D.), +18 kV
applied voltage, a temperature of 20 °C and direct UV detection at 280 nm. The method was applied to different plant food
samples. (+)-Catechin and (−)-epicatechin could be verified as the most common flavan-3-ols. In the case of guaraná, however,
we were able to identify all four enantiomers, both (+)- and (−)-catechin and (+)- and (−)-epicatechin, as naturally occurring
compounds. This finding was verified by further isolation and purification of the flavan-3-ols and subsequent LC–MS analysis.
This method allows for the identification of the authenticity of guaraná through the analysis of the catechin and epicatechin
enantiomers, additionally to the conventional methods like HPLC. 相似文献