bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Wax Coating on the Surface Quality of EPS Patterns for Solid Mould Investment Casting
Authors: Guler Kerem Altug 
Published: December 2013

Abstract
Expandable polystyrene (EPS) foam has been a well-known pattern material for a long time in the investment casting process, however it always suffers from insufficient surface finish compared to wax patterns. In this study, EPS foam patterns were coated with waxes and the effects of such coating on the surface quality were investigated. Cubic shaped EPS patterns were coated with liquid ordinary candle wax (c-wax) and commercial pattern wax (p-wax). These patterns and an uncoated pattern were used to prepare plaster bonded solid investment casting moulds and a A319 aluminium alloy was casted into these moulds. Average surface roughness (Ra) of the patterns, moulds internal surfaces and cast parts were measured, cross sections of the coated patterns were investigated by optical microscopy and the coating thicknesses were measured with an image analyser. As an obvious result, wax coating significantly increases the surface quality and the p-wax creates smoother, while the c-wax creates more uniform coating films.
Production of Self-Compacting Lightweight Concrete with Pumice Aggregate
Authors: Açıkel Hicran , Günaydın Murat 
Published: December 2013

Abstract
This study aimed to produce self-compacting normal weight concrete by the use of lightweight aggregate, which has become more widespread, as Turkey has many natural lightweight aggregate sources. Nevşehir pumice aggregate was used in the tests. The characteristics of fresh concrete incorporating additives as fly ash and super plasticizer were determined via self-compacting concrete tests such as slump flow, V-funnel and L-box flow. Compression, flexure and split tests were conducted on cube, cylinder and girder samples produced with the concrete. The test results and strength data showed that self-compacting lightweight concrete could be produced by the methods used in this study.
Tomografische Methoden für die Brennstoffzellenforschung∗
Authors: Arlt Tobias , Grothausmann Roman , Manke Ingo , Markötter Henning , Hilger André , Kardjilov Nikolay , Tötzke Christian , Banhart John , Kupsch Andreas , Lange Axel , Hentschel Manfred P. , Krüger Philipp , Haußmann Jan , Hartnig Christoph , Wippermann Klaus 
Published: December 2013

KurzfassungAufgrund des hohen Wirkungsgrades und der vielfältigen Einsatzmöglichkeiten können Brennstoffzellen einen wichtigen Beitrag zur zukünftigen Energieversorgung leisten. Für die Optimierung der Brennstoffzellentechnik ist es erforderlich, die während des Zellbetriebs ablaufenden Prozesse zu verstehen und exakt zu charakterisieren. Ein ausbalanciertes Wassermanagement ist die Grundlage für die optimale Leistungs­fähigkeit einer wasserstoffbetriebenen Zelle. Das während des Betriebs entstehende Wasser muss die Membran ausreichend befeuchten, um deren Protonenleitfähigkeit aufrechtzuerhalten. Andererseits behindern zu große Wasseransammlungen in der Zelle die Gaszufuhr durch die porösen Materialien sowie in den Kanälen der Gasverteilerstrukturen. Alterungsphänomene einzelner Zellkomponenten können die Verteilung der Wasseransammlungen und somit das Wassermanagement empfindlich stören und so die Leistungsfähigkeit der Brennstoffzelle herabsetzen. Zur Analyse der Wasserverteilung werden zerstörungsfreie, bildgebende Methoden, wie die Ex-situ-Neutronentomografie und die In-situ-Synchrotronradiografie, eingesetzt. Diese Methoden können während des Brennstoffzellenbetriebs mit weiteren Messverfahren, beispielsweise der ortsaufgelösten Stromdichtemessung, kombiniert werden. Auf diese Weise werden einzelne Komponenten, wie zum Beispiel die Gasdiffusionsschichten, charakterisiert.
Experimental Study of Imida zoline as an Inhibitor of Carbon Steel in Acid Media
Authors: Alar Vesnar , Juraga Ivan , Stojanoviæ Ivan , Šimunoviæ Vinko , Borko Tihomir 
Published: December 2013

AbstractThe electrochemical behaviour of a carbon steel in deaerated acid media with concentrations of 20 ppm, 50 ppm, 100 ppm and 200 ppm imidazoline at different temperatures and with different stirring rates has been evaluated by using anodic and cathodic polarization curves (Tafel) and electrochemical impedance spectroscopy (EIS) to compare the corrosion inhibition efficiency. The experimental results suggest that imidazoline is a good corrosion inhibitor at 50 ppm concentration.
Wear Behaviour of Heat Treated 100Cr6 Steels
Authors: Polat Şeyda , Türedi Enbiya , Atapek Ş. Hakan , Köseoğlu Merve 
Published: December 2013

Abstract
In this study, several heat treatments were applied to DIN 100Cr6 steel to obtain different matrices. In the first stage of the study, solution annealing treatment was applied to the steel and cooling was carried out in various media (furnace, oil, and salt bath). In order to eliminate the stresses after transformation from austenization, a low temperature tempering treatment was applied to the quenched samples. All heat treated samples were examined using light microscopy after metallographic preparations. In the second step, ‘ball-on-disc’ type tribometer was used to determine the friction coefficient of the steels depending on the matrix phase. Weight loss was recorded and the friction coefficient versus distance was plotted for each steel. Worn surfaces of the steels were examined using scanning electron microscopy to characterize the wear mechanisms. It turned out that (i) pearlitic, bainitic and martensitic matrices could be obtained depending on the cooling medium, (ii) martensitic matrix had higher wear resistance based on its weight loss, (iii) abrasive and adhesive wear tracks were present on the worn surfaces of the steels.
Fatigue Behaviour Monitoring of an AISI 1045 Carbon Steel using the Statistical-Based Z-Notched Approach
Authors: Padzi Mahfodzah Md , Abdullah Shahrum , Nuawi Mohd Zaki 
Published: December 2013

Abstract
In this work, three percentages of constant loading are used for fatigue failure assessment. Fatigue behaviour under these three percentages of constant loadings is analyzed by using a new statistical-based approach known as integrated kurtosis-based algorithm for Z-notch filter (I-kaz). Fatigue tests were performed according to ASTM E466-96 standard with a strain gauge attached to the specimen being tested. A fatigue test was conducted under three loadings between 600–700 MPa and at a frequency of 8 Hz. A set of data acquisition systems was used to collect the fatigue strain signals. The I-kaz technique, which provides an I-kaz coefficient and a three-dimensional (3D) graphic, was used to describe and to evaluate the fatigue failure activities. The trends of I-kaz coefficients and of 3D graphics were compared to explain the fatigue damage induced by the three loadings.
Experimental and theoretical investigations on diffusion process for rare earth ores
Authors: He Ye , Li Wenzhi Z. 
Published: December 2013

Abstract
The diffusion reaction kinetics of weathered crust elution-deposited rare earth with mixed ammonium salts was studied. The influence of concentration of reagents and particle size of ore on diffusion rate was investigated. The results showed that the diffusion process and diffusion rate could be improved by increasing reagents concentration and decreasing diffusion flowing rate and particle size. The diffusion process could be explained with the shrinking core Model, which could be controlled by the diffusion rate of reacting reagents in porous solid layer.
Manual and Automatic Determination of the Plastic Strain Ratio
Authors: Bocz András , Márkus Dénes , Narancsik Zsolt 
Published: December 2013

Abstract
ISO 10113:2006 standard includes determination of plastic anisotropy (r-value). The r-value is one of the indices of the ductility of cold-rolled steel sheets. The article compares manual and automatic mathematical methods and their results.
Mechanical and Corrosion Resistance of (Ti,Cr)N Grown by DC Magnetron Sputter on H13 Tool Steel
Authors: Taweesup Kattareeya , Tungasmita Sukkaneste , Yongvanich Niti , Lothongkum Gobboon , Visuttipitukul Patama 
Published: December 2013

Abstract
This research studied properties of (Ti,Cr)N film prepared by co-deposition from dual unbalanced DC magnetron sputtering techniques at various temperatures. All samples were prepared at different growth temperatures for (Ti,Cr)N compound layer with atomic ratio Ti: Cr approximately 1: 1. The lattice parameter of the film is 4.18 Å, which is a value between those of TiN and CrN. It was found that both hardness and adhesion increased with an increase of growth temperature. The highest hardness value obtained is 24.78 GPa for film growth at 190 °C and film adhesion was significantly improved by increasing growth temperature. The growth temperature also plays an important role on corrosion resistance. Ecorr increases from −466 mV to −195 mV, while Icorr decreases from 188.21 nA/cm2 to 3.20 nA/cm2 with increasing the growth temperature to 190 °C. At highest growth temperature surface roughness decrease. The improved properties, both mechanical and corrosion properties, as well as surface uniformity are due to the change of film structure from columnar to equiaxial, which produces a denser film.
Messunsicherheit bei der Ermittlung des E-Moduls im Zugversuch an Stahl∗
Authors: Weißmüller Christian , Frenz Holger 
Published: December 2013

Kurzfassung
Der E-Modul gehört zu den wichtigsten Werkstoffkennwerten. Die Ermittlung soll zukünftig in einem Anhang zur DIN EN ISO 6892-1 geregelt werden. Im Rahmen einer internationalen Eignungsprüfung wurden Richtigkeit und Messunsicherheit der E-Modulbestimmung untersucht. Die Bundesanstalt für Materialforschung und –prüfung stellte dazu besonders qualifizierte Referenzproben zur Verfügung. Die Ergebnisse zeigen, dass die Anforderungen an die einzusetzenden Messgeräte hoch sind und die berechneten Unsicherheitsbudgets zu fachlich sinnvollen Werten führen.
Investigation of Plasma Arc Cutting Parameters With Type-2 Fuzzy Set and System
Authors: Çelik Yahya Hışman , Özek Müzeyyen Bulut , Özek Cebeli 
Published: December 2013

Abstract
The objective of the present study was it to design a type-2 fuzzy set and system in order to predict surface roughness and hardness depending on the parameters (material thickness, cutting speed, arc voltage and current) of the plasma arc cutting process of S235JR sheet materials. Therefore, some experimental studies were conducted. The experimentally determined data were used to describe the type-2 fuzzy set and system. Type-2 fuzzy set and system was found to be usefull to predict surface roughnes and hardness. According to the obtained values, the best surface roughness and the values closest to the hardness of the raw material were obtained at 1500 mm/min cutting speed, 8 mm material thickness, 115 V arc voltage and 80 A current.
Current international activities to increase fire protection knowledge for nuclear power plants
Authors: Berg H. P. , Riese O. , Röwekamp M. 
Published: December 2013

Abstract
For nuclear power plants fire events are of high safety significance since they have the potential to damage more than one redundant safety train simultaneously. Within the frame of the recently started second series of periodic safety reviews, a probabilistic fire risk assessment has to be performed in addition to the deterministic analysis. Therefore, realistic fire occurrence frequencies as well as appropriate validated fire models and simulation codes are needed. All these complex issues require internationally harmonized activities to gain consistent, reliable and traceable information as well as to reduce the costs. Presently, three international activities are ongoing: the OECD-FIRE project with the goal to establish a quality assured and consistent international fire event database, and two further activities. In the frame of one of these fire models and computer codes shall be evaluated and validated based on real scale experiments under as far as possible realistic boundary conditions in order to support their extended use for decision making. The other one aims on analyzing fire induced electric failures of safety related systems and components. The objectives of the international co-operations and the first results are presented.
Accelerator driven systems for transmutation and energy production: challenges and dangers
Authors: Brandt R. , Birkholz W. , Shelaev I. A. 
Published: December 2013

AbstractAccelerator Driven Systems (ADS) are an old technological idea: Relativistic proton accelerators deliver their beams onto massive heavy element targets, thus producing abundant neutron fluences. Placing this target into sub-critical nuclear fission assemblies is yielding substantial fission reactions, thus additional fission energy (Rubbia called such a system “Energy Amplifier”). This technology has recently attracted considerable attention due to advances in the construction of powerful accelerators. It allows the safe and cheap production of nuclear energy simultaneously with the destruction (Transmutation) of long lived radioactive waste, in particular plutonium and other minor actinides (neptunium and americium). The principles and the present-state-of-the-art are described, including first experiments to transmute plutonium this way. This technology needs, however, many more years of further “research and development” before large scale ADS's can be constructed. It may be even necessary to investigate the question, if all basic physics phenomena of this technology are already sufficiently well understood.
Calculation of control plates life time and worth at the ETRR-2 research reactor
Authors: Aziz M. 
Published: December 2013

Abstract
A detailed three-dimensional MCNP model of the ETRR-2 research reactor has been developed for the analysis of the neutronic parameters of the reactor. The model was used to determine the partial control plates reactivity worth and the behavior of the worth with time. The results of the present model were compared with the experimental measurements for partial control plates reactivity worth and with the design calculations for control plates behavior with time. The comparisons indicate satisfactory agreement.
Optimisation of occupational exposures during site remediation at WISMU
Authors: Schmidt P. , Wolf F. 
Published: December 2013

Abstract
Since 1991 the national corporation WISMUT GmbH has been charged with the rehabilitation of the sites of former Uranium mining and milling in East Germany. Since decommissioning and site remediation are carried out at places with enhanced dose rates and high concentrations of airborne radioactivity (Rn-222, long-lived alpha emitters), a large part of the employees is classified as occupational exposed radiation workers. Thus, in 2002, 1,073 workers were engaged with relevant works in radiation protection areas aboveground (radiation exposed workers of category B; mean effective dose: 0.3 mSv; maximum dose: 2.2 mSv), and 514 workers still prepared by underground activities the flooding of the Uranium mines (category A; mean effective dose: 0.9 mSv; maximum effective dose: 4.9 mSv). The paper presents the measures taken by WISMUT to optimise the occupational exposure. The need for implementing appropriate ALARA methods in the field of occupational exposure is last but not least caused by the fact that for a number of employees the integral exposure over the total working life time has exceeded already the 400 mSv figure.
Airborne measurement of radioactivity by learjet 35A
Authors: Dyck W. , Brust H. , Dalheimer A. , Steinkopff Th. 
Published: December 2013

Abstract
In case of a radioactive emergency radioactive plumes may be expected in heights up to the tropopause. For this reason aircraft measurements are necessary as a supplement to ground-based measuring sites. The authors present an aircraft type Learjet 35A used for localizing and analyzing radioactive contaminated air masses up to 12,000 m. The aircraft is equipped with an isokinetic high-volume sampler to collect aerosols on filters outside the pressurized cabin and an onboard gamma spectrometry system with a high purity germanium detector to analyze the filters during flight as well as a dose ratemeter, a radon daughter monitor and equipment to collect gaseous iodine and noble gases. The meteorological parameters temperature, atmospheric pressure, relative humidity, wind speed and wind direction are determined as well. Resulting data are transmitted from the plane to the headquarter of the German Meteorological Service (Deutscher Wetterdienst, DWD) and used for verifying the prognosis.
Survey of decommissioning projects
Authors: Rehs B. , Kaulard J. 
Published: December 2013

Abstract
Worldwide, 104 power and prototype reactors, 382 research reactors and 247 facilities of the nuclear fuel cycle have been shut down and are in different phases of decommissioning or decommissioning has already been completed. With 18 shut down power and prototype reactors, 11 shut down research reactors with a power of more than 50 kWth and with 10 shut down facilities of the nuclear fuel cycle Germany belongs to those countries with a lot of experience in decommissioning. This pertains not only to the number of shut down installations but also to the variety of different types. Further countries with a high degree of experience in decommissioning are among others the United States of America, the United Kingdom and France.
Decommissioning of gas-cooled reactors
Authors: Sterner H. , Cross M. T. , Rodriguez A. 
Published: December 2013

Abstract
Gas-cooled reactors represent an important part of the world's nuclear programme. A wide spectrum of designs has been developed and tested. The majority of these test reactors and 1st generation of power reactors has been shut down and is now in different stages of decommissioning. This is also the case for the pilot power reactors of the types High Temperature Gas-cooled Reactor (HTGR) and Heavy Water Gas-cooled Reactor types (HWGCR). Gas-cooled reactors show major generic design characteristics different from Light Water Reactors (LWR), hence influencing the choice of decommissioning strategy, waste/material management and also to a certain extent the decommissioning techniques and procedures applied. The most important issue influencing the decommissioning is the presence of large amounts of graphite in most of these reactors. The majority of the shut-down reactors is located in the UK and in France and major decommissioning programmes are under way in these countries. Interesting decommissioning work has also been carried out in Germany and in the USA. Most reactors are in a stage of safe enclosure. However, decisions have been taken recently to perform direct complete dismantling, notably in France, Italy and, to a certain extent, in Germany.
Decommissioning of reactors after accidents
Authors: Ackermann L. 
Published: December 2013

Abstract
The decommissioning is the final phase in the life cycle of a nuclear reactor. In case of finishing the operation after the foreseen lifetime the decommissioning is planned long-dated with regard to the options “immediate dismantling”, “safe enclosure” and “entombment”. In case of an accident the operational phase was mostly finished immediately depending from the possible options for managing the damaged facility. With regard to the accidents in the nuclear power plants Three Mile Island Unit 2 (USA), Lucens Experimental Reactor (Switzerland), A-1 (Slovakia) and Chernobyl-4 (Ukraine) this article presents a short description of these accidents and of the related decommissioning projects. The examples demonstrate that in principle these projects represent variations of the above mentioned options. It has, however, to be noted that the realisation of the entombment of the destroyed unit Chernobyl-4 is unique with regard to the essential high complexity related to the first and the second Sarcophagus.
Positive temperature reactivity coefficient of a TRIGA reactor at room temperature
Authors: Žagar T. , Ravnik M. 
Published: December 2013

Abstract
A positive isothermal temperature reactivity coefficient has been measured at zero power conditions at the TRIGA research reactor of the J. Stefan Institute in Ljubljana. The coefficient is measured in a critical reactor for different core configurations at room temperature and at low power. The reactor is filled with standard, 20 % enriched, fuel elements containing 12 wt % uranium with 6 % average burn-up. The experiments are analysed by reactor calculations using WIMSD code to provide the reactor physics explanations of the results measured. The positive temperature reactivity effect can be explained by reduced absorption in water prevailing at low fuel temperature over negative temperature effects on the reactivity in the fuel elements. The positive effect is due to the thermal spectrum shift in water and is not the consequence of a change in water density. The positive effect decreases with increasing temperature. The negative reactivity effect in fuel prevails at fuel temperatures above 50°C. The positive isothermal temperature reactivity coefficient has no effect on normal reactor operation in steady state and pulse mode.
Design stability and safety margins of the ETRR-2 core cooling system regarding seismic loads
Authors: Ahmed K. 
Published: December 2013

Abstract
The seismic design of a nuclear power plant includes two levels of design earthquake, the safe shutdown earthquake (SSE) and the operating basis earthquake (OBE). The OBE and SSE are considered in the nuclear power plant design as required by the IAEA safety regulations. A typical piping model for the ETRR-2 core cooling system includes ASME-class 1, 2 and 3 piping and was analyzed with regard to both IAEA safety regimes. A load combination, as stated by the IAEA Safety Guide 50-SG-S2, has been considered. The safety guide requires that the OBE should equal to at least one half SSE and that the plant should be shut down if exposed to earthquake intensity greater than the OBE. The results reflect the requirement for the precise design of a supporting system to accommodate for higher seismic peaks more than 0.2 g and the system needs to be more flexible.
Safety and security of radioactive sources – international provisions
Authors: Czarwinski R. , Weiss W. 
Published: December 2013

Abstract
For more than 50 years radioactive sources are used beneficially world-wide in medicine, industry, research and teaching. In the early 50ies mainly Ra-226 sources were used especially for medical applications. In the mean time a great number of radio-nuclides with more or less risk to individuals, society and environment are used. The number of these sources is increasing. The available experience with the application of sealed sources in industry, medicine, research and teaching shows that despite the widespread use of such sources a high level of safety can be achieved. One precondition is that the regulatory control of a radioactive source has to be carried out consistently during the life cycle of the sources – “from cradle to grave”. Particular attention has to be given to the so-called orphan sources which are not subject to regulatory control, either because they have never been under control, or because they have been lost, misplaced, abandoned, stolen or transferred without proper authorisation. The concern about orphan sources arising from poor safety and security standards of radioactive material around the world resulted in intensive global actions especially in the light of the security situation after the 11th September 2001. The improvement of regulatory control is one of the key elements in preventing people, goods and environment from being exposed exceptionally by the misuse of radioactive sources. Important steps toward the improvement of the safety and security of high radioactive sources are the IAEA Code of Conduct on the Safety and Security of Radioactive Sources and the European Directive on the Control of High Activity Sealed Radioactive Sources and Orphan Sources.