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Metal Injection Molding (MIM) was performed with water atomized and gas atomized 316L stainless steel powders and powder blends thereof. Feedstocks were prepared using a thermoplastic binder system and subsequently molded into tensile test specimens. Different debinding procedures and sintering treatments were applied and their influence on carbon content in the product was compared. Chemical decomposition processes of the binder and the influence of powder morphology on debinding and sintering behaviour are discussed. Shrinkage of the MIM-fabricated parts was examined and correlated to the powder characteristics. As a result a procedure is suggested to achieve mechanical properties expected for 316L stainless steel.  相似文献   
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For more than 15 years, systems for monitoring the integrity of the primary system and for the diagnosis of nuclear power plant components have been manufactured by Siemens (KWU). These systems record the vibrational behaviour of reactors and their internals and of principal components of the primary system (SÜS), indicate the presence of loose parts or parts that have become detached within the pressure boundary of the primary system (KÜS), detect and locate leaks in piping, tanks and vessels (ALÜS, FLÜS), and evaluate the fatigue of nuclear power plant components as a result of the pressure and thermal stresses to which they are subjected (FAMOS).  相似文献   
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FINITE ELEMENT SIMULATION OF ROUGH RICE DRYING   总被引:1,自引:0,他引:1  
Milled, brown and rough rice samples were dried in the laboratory with heated air and diffusivities of the endosperm, bran and husk were evaluated with a search technique using the finite element method. The endosperm had the highest diffusivity. The husk had a slightly higher diffusivity than the bran because the trapped air inside the husk was considered as an integral part of the husk. The finite element method predicted rough rice drying that was in good agreement with experimental results.  相似文献   
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Das Verhältnis der Vergleichbarkeit zwischen den Laboratorien zu der Wiederholbarkeit innerhalb der Laboratorien bei der Erstellung von analytischen Informationen läßt auf systematische Unterschiede zwischen den Laboratorien schließen. Die so konstatierte unterschiedlich gute Beschreibung der Realität soll durch Erzeugen analytischer Informationen größtmöglicher Richtigkeit verbessert werden. Das wird erreicht durch Referenz; das ist eine definierte Atomzahl des Analyten, die nach einer Voranalyse durch Rekonstitution der Probenportion in Form einer festen oder flüssigen Lösung den gleichen physikalischen und chemischen Bedingungen ausgesetzt wird wie die Analysenprobe. Es werden der Produktion angepaßte sekundäre Referenzproben erzeugt für die Eichkontrolle der Analysengeräte nach mehreren Methoden. Dabei soll schließlich durch minimalen Aufwand eine maximale Übertragung des Vertrauens in die Referenz auf den Analyten in der Analysenprobe gesichert werden.  相似文献   
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The solubility of titanium nitride in liquid iron is described by the solubility product log([%Ti][%N])1 = ?17040/T + 6.40 reported by Turkdogan. The solubility in δ ferrite measured by Kunze is log<[%Ti][%N])δ = ?17205/T + 5.56. Combining the solubilities in both phases and the solubilities of nitrogen the distribution equilibrium of titanium can be derived. It is characterized by the thermodynamic distribution coefficient kδ/Io,Ti = [%Ti]δ/[%Ti] = 0.40. By zone melting and secondary ion mass spectrometry of the titanium distribution kδ/ITi = 0.53 was measured. An analysis of all known data led to kδ/Io,Ti = 0.40…0.50. Measurements of the TiN solubility in austenite by heat treatment were not significant. They led to distribution coefficients between 0.07 and > 1. By zone melting in a carburizing atmosphere a distribution coefficient kγ/ITi = 0.12 was measured. From a thermodynamic analysis performed by Ohtani et al., from the TiN solubility in the melt, and from the solubilities of nitrogen kγ/Io,Ti = 0.13 was deduced. Basing on the distribution equilibria of titanium and nitrogen and on the measured temperature dependence the solubility product log([%Ti][%N])γ = ?15000/T + 4.06 was obtained.  相似文献   
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2D soft nanomaterials are an emerging research field due to their versatile chemical structures, easily tunable properties, and broad application potential. In this study, a benzene‐bridged polypyrrole film with a large area, up to a few square centimeters, is synthesized through an interfacial polymerization approach. As‐prepared semiconductive films exhibit a bandgap of ≈2 eV and a carrier mobility of ≈1.5 cm2 V?1 s?1, inferred from time‐resolved terahertz spectroscopy. The samples are employed to fabricate in‐plane micro‐supercapacitors (MSCs) by laser scribing and exhibit an ultrahigh areal capacitance of 0.95 mF cm?2, using 1‐ethyl‐3‐methylimidazolium tetrafluoroborate ([EMIM][BF4]) as an electrolyte. Importantly, the maximum energy and power densities of the developed MSCs reach values up to 50.7 mWh cm?3 and 9.6 kW cm?3, respectively; the performance surpassing most of the 2D material‐based MSCs is reported to date.  相似文献   
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