bluuebunny/crossref_metadata_2025_split huggingface dataset:
Safe product design – the role of the NDT reliability analysis
Authors: Pavlovic Mato , Mueller Christina , Ewert Uwe , Ronneteg Ulf , Pitkänen Jorma , Boller Christian 
Published: December 2013

Abstract
In line with the damage tolerance design principles, an adequate non-destructive inspection system is needed to ensure structural integrity. Yet, when pushed to the limits of their detection capability, non-destructive evaluation systems do not produce consistent hit/miss indications. Their capability of detecting flaws is therefore expressed as a probability of detection. In the conventional signal response reliability analysis, the probability of detection is expressed as a function of the flaw size. The adequacy of the inspection system is verified by comparing the size of the flaw that is reliably detected with the maximum allowable flaw size, which will not undermine the structural integrity. Analyses of modern structures show that other parameters also determine the severity of the flaw for the structure. Within the multi-parameter reliability analysis, the probability of detection can be expressed as a function of diverse influencing parameters. When determining the adequacy of the non-destructive evaluation system, the capability of detecting a flaw has to be expressed and checked against the critical value of exactly that parameter that determines flaw severity for the structure. Failing to do so can lead to a rejection of the healthy, or acceptance of the bad part. The principle is demonstrated on the transmit-receive longitudinal ultrasonic inspection data of the iron cast component with surface, semi-elliptical, crack-like flaws.
Fabrication and Characterization of Bimetallic Mordenite-Zeolite Catalysts for Low Temperature Direct Decomposition of N2O Emitted from Nitric Acid Plants∗
Authors: Seo Minhye , Cho Sung-Su , Kwyon Byung-Chan , Lee Sungkyu 
Published: December 2013

Abstract
In this research, the mordenite based catalysts for direct decomposition of N2O have been prepared and characterized for their direct decomposition performance at the operating temperature of 300–550 °C commonly encountered in the nitric acid plants tail gases. The zeolite catalyst was prepared by 2 steps: 1. Precursor wet ion exchange, 2. Precursor impregnation. The bi-metallic catalyst thus prepared shows an excellent N2O decomposition performance. The total conversion efficiency of Pt-Fe-MOR catalyst has been achieved at 390 °C. XPS analysis confirmed platinum on mordenite supports in two forms: PtO and PtO2 species interact with oxygen ions at the metal/support interface. Deposition of Pt as a promoter on the surface of Fe-mordenite results in a considerable enhancement of catalytic activity.
Sea Water Effect on Failure Behaviour of Mechanically Fastened Composites
Authors: Sayman Onur , Ozen Mustafa , Sen Faruk , Benli Semih 
Published: December 2013

Abstract
In this study, sea water effect on failure behaviour was investigated for mechanically fastened composites that are oriented as [0/90/45/-60]s. The laminated composite specimens were fastened with two serial fasteners and were tested under non-immersed and immersed conditions, i. e. in sea water for 200 days. The experiments were carried out according to D 5229/D 5229M standard test method for evaluation of moisture absorption properties and equilibrium conditioning of polymer matrix composite materials. The results point out that the immersion into sea water of the composite specimens can cause a decrease in failure loads of both, pinned and bolted joints, particularly.
Herausforderungen bei der Auslegung und produktionstechnischen Umsetzung von Verbundlenkerhinterachsen für PKW∗
Authors: Frehn Andreas , Linnig Wolfram , Niggemeyer Norbert 
Published: December 2013

Abstract
Aufgrund der immer kürzer werdenden Entwicklungszeiten und des zunehmenden Kostendrucks bei der Entwicklung von Fahrzeugen und Komponenten wird die virtuelle Entwicklung weiter an Stellenwert gewinnen. Am Beispiel einer Verbundlenkerachse wird gezeigt, welche Kriterien bei der Auslegung dieses Bauteils berücksichtigt werden müssen, deren Verifizierung und Optimierung kontinuierlich über geeignete Test- und Untersuchungsverfahren erfolgen muss. Durch die virtuelle Validierung werden die Fertigungsprozesse variabel festgelegt, die notwendig sind, um die Anforderungen hinsichtlich Betriebsfestigkeit sicher zu erfüllen. In Kombination mit geeigneten Werkstoffen und Halbzeugen leisten diese einen wichtigen Beitrag zum Leichtbau und zur damit verbundenen Einsparung von CO2.
Schwingfestigkeit von Schweißnahtenden und Übertragbarkeit von Schweißverbindungswöhlerlinien∗
Authors: Kaffenberger Matthias , Vormwald Michael 
Published: December 2013

Abstract
Um die Geometrieeinflüsse von Schweißnahtenden genau erfassen zu können, wurden repräsentative Nähte mit einem hochauflösenden dreidimensionalen (3D) Scanner aufgenommen. Aus den gescannten Oberflächen konnten Volumenmodelle erstellt und anhand der Methode der finiten Elemente (FEM) elastizitätstheoretische Kerbspannungen berechnet werden. Aus diesen Ergebnissen wurde ein idealisiertes Nahtendmodell abstrahiert, welches in Bezug auf Größe und Verteilung nahezu die gleichen Kerbspannungen liefert wie die reale Geometrie. Zur Übertragbarkeit der Schwingfestigkeitsdaten wurde der spannungsmechanische und statistische Größeneinfluss in neuer Form kombiniert. Zur Lösung dieses Ansatzes wurde das numerische Verfahren NuMeSiS erarbeitet.
A general approach to automatic measurements of water velocity
Authors: Fu X. Q. , Liang X. , Liu X. , Liao W. T. 
Published: December 2013

Abstract
Real-time measurement of river flow velocity below the ice in winter is a tough problem. An experimental apparatus of a new thrust flow transducer based on the properties of particle phase is proposed in this paper. The traction cable's pull force which is given by the floating ball in the fluid can be measured by the experimental apparatus. Then the force values of the rigid floating ball are used to calculate fluid thrust on the floating ball. Finally, the velocity can be evaluated by an empirical formula between the fluid velocity and fluid thrust on the floating ball. Such a new thrust flow transducer is simple and requires only low costs. It can not only be used for measuring the surface velocity of rivers, water channels, lakes, and oceans, but can also be used for automatic measuring the velocity of water including frazil slush which is found below the ice sheets of rivers, water channels, lakes, and oceans in freezing conditions.
On the Biaxial Distribution of Anisotropic Elastic Modulus of Thin-Plate Polycrystalline Elements and the Identification by Ultrasonic Methods
Authors: Levi Avram Sabetaj 
Published: December 2013

Abstract
A new method for the interpolation of biaxial anisotropy of elastic modulus of thin-plate polycrystalline elements has been developed. The dependence of shear modulus and modulus of longitudinal elasticity as a function of an angular distribution of Poisson's ratio, achieved by the method of ultrasonic critical-angle refractometry (UCR), has been derived.
Einfaches Korrigieren des Hinterleuchtens von Röntgendetektoren
Authors: Kupsch Andreas , Hentschel Manfred P. , Lange Axel , Müller Bernd R. 
Published: December 2013

Kurzfassung
Hinterleuchten stellt eine oft unerkannte Fehlweisung in der radiographischen Abbildung mit Flächendetektoren dar, die durch diffuse Umverteilung der Intensität verursacht wird. Dieser Effekt kann die korrekte Transmissions-Intensität eines Probekörpers gemäß dem Lambert-Beer'schen Gesetz erheblich verfälschen. Hinterleuchten wird sowohl mit Bremsstrahlung von Röntgenröhren als auch mit monochromatischer Synchrotronstrahlung beobachtet. Die fehlerhaft reduzierten Schwächungskoeffizienten von einigen 10 % korrelieren mit der Strahlschwächung und dem direkt bestrahlten Detektorbereich. Für eine einfache numerische Korrektur des Hinterleuchtens werden lediglich integrale Intensitätswerte benötigt.
Neue Methoden zur Analyse von diffusiblem Wasserstoff in hochfesten Stählen∗
Authors: Kühn Sebastian , Unterumsberger Fabian , Suter Thomas , Pohl Michael 
Published: December 2013

Kurzfassung
Seit einigen Jahren werden für technische Konstruktionen vermehrt hochfeste Stähle mit Werkstofffestigkeiten von bis zu 2000 MPa eingesetzt, wie z. B. in der Automobilindustrie. Für den sicheren Einsatz von hochfesten Stählen ist es notwendig, kritische Wasserstoffgehalte und Belastungen zu kennen, bei denen nicht mit einer Beeinträchtigung der mechanisch technologischen Werkstoffeigenschaften und einem Materialversagen (Delayed Cracking) zu rechnen ist. Da hochfeste Stähle bereits bei sehr geringen Wasserstoffgehalten unter Zugbeanspruchung eine verzögerte Rissbildung aufweisen können, muss eine Wasserstoffanalysetechnik eingesetzt werden, welche eine exakte und reproduzierbare Analyse des schadensursächlichen diffusiblen Wasserstoffs im Bereich kleiner 0,1 ppm unabhängig vom Gesamtwasserstoffgehalt ermöglicht. In diesem Beitrag werden ein Verfahren zur hochgenauen integralen Analyse des diffusiblen Wasserstoffgehalts (HCA-Verfahren = Hydrogen Collecting Analysis) und ein elektrochemisches Verfahren zur Analyse von diffusiblem Wasserstoff in kleinen Werkstoffbereichen vorgestellt.
Mechanical Testing of Flow Drill Screw Joints Between Fibre-Reinforced Plastics and Metals
Authors: Szlosarek Robert , Karall Thomas , Enzinger Norbert , Hahne Clemens , Meyer Nils 
Published: December 2013

Abstract
The paper describes a novel testing method for mechanical joints between fibre-reinforced plastics and metals. As an example, the paper discusses a connection between a continuous carbon-fibre-reinforced plastic and aluminium via a flow drill screw. The failure load of the joints under different loading angles was tested with the help of a modified KS-II testing facility. A detailed analysis of the damage and failure behaviour of the connection was performed by means of optical recordings and micrographs. The results indicate that the tested material combination has nearly the same failure load at different loading angles with various failure mechanisms. The experimental results can be used to devise new failure criteria for these connections and to detect limit values for the design process.
Effects of Cobalt and Nickel/Cobalt Additions to P/M 304L Stainless Steel on Oxidation Behaviour at 900 °C and Mechanical Properties
Authors: Uoonahaseth Prangtip , Wangyao Panyawat , Lothongkum Gobboon , Chuankrekkul Nutthita , Tongsri Ruangdaj , Visuttipitukul Patama 
Published: December 2013

Abstract
This research investigated the effects of various cobalt and nickel/cobalt additions to P/M 304L stainless steel on oxidation behavior at 900 °C, hardness and bending strength. A single action press at 498 MPa was used for compacting powder mixture specimens. They were then sintered at 1300 °C for 30 minutes in hydrogen atmosphere and heat treated at 900 °C for 2, 5, 10, 20, 25, 40, 60, 80 and 100 hours in air for oxidation tests. It is clearly shown in the results that cobalt addition could improve density, hardness and bending strength. However, only 1 wt.-% Co addition was the best condition for oxidation resistance. The detrimental effect of Ni addition dominated the beneficial effect of Co addition, because its bigger powder size led to more pore formation. The resulting mechanical properties and oxidation behaviour depend on microstructures, porosity and powder size.
Mobile X-Ray Computed Tomography for Nuclear and Aviation Industry
Authors: Redmer Bernhard , Ewert Uwe 
Published: December 2013

Abstract
Digital detectors such as phosphor imaging plates (IP) and digital detector arrays (DDA) enable radiographic inspection with higher efficiency and improved image quality in comparison to the classic film technique. The mobile mechanised tomographic system TomoCAR (tomographic computer aided radiology) was developed first for inspection of circumferential welded seams of pipes. It consists of the manipulator based position control of an X-ray tube in front of the region to inspect and a digital detector array behind it. The high contrast sensitivity technique was combined with planar tomography. The tomographic reconstruction allows the three-dimensional (3D) representation of the material structure and included defects, equivalent to a metallographic cross sectioning. The hardware design is based on a specially developed flat X-ray tube and a direct converting CMOS detector array on CdTe basis. TomoCAR is applied for sizing of volumetric and planar defects. It allows the reliable detection of planar defects with openings larger than 25μm by subpixel resolution due to the achieved high signal-to-noise ratio. TomoCAR was successfully qualified as the result of a German pilot study on the basis of the European Network of Inspection and Qualification (ENIQ) guidelines for application in the nuclear power industry. Application examples are presented. The TomoCAR design was modified for in situ inspection of large aircraft components under production conditions. A gantry gate based planar tomograph was constructed and tested for inspection of the integrity of large flat CFRP panel components of up to 3 m × 9 m size. The integrity of imbedded stringers has been successfully observed. Different trials were performed to prove the finding rate of cracks in embedded stringers, which will be presented and discussed.
Theoretical and experimental investigations into natural circulation behaviour in a simulated facility of the Indian PHWR under reduced inventory conditions
Authors: Kumar N. V. Satish , Nayak A. K. , Vijayan P. K. , Pal A. K. , Saha D. , Sinha R. K. 
Published: December 2013

Abstract
A theoretical and experimental investigation has been carried out to study natural circulation characteristics of an Indian PHWR under reduced inventory conditions. The theoretical model incorporates a quasi-steady state analysis of natural circulation at different system inventories. It predicts the system flow rate under single-phase and two-phase conditions and the inventory at which reflux condensation occurs. The model predictions were compared with test data obtained from FISBE (Facility for Integral System Behaviour Experiments), which simulates the thermal hydraulic behaviour of the Indian 220 MWe PHWR. The experimental results were found to be in close agreement with the predictions. It was also found that the natural circulation could be oscillatory under reduced inventory conditions.
A method for in-situ quantification of oxygen in oil using fast neutron activation analysis
Authors: Owrang F. , Mattsson H. , Nordlund A. 
Published: December 2013

AbstractThe feasibility of an experimental methodology for in-situ quantification of oxygen in bulk oil using fast neutron activation analysis (FNAA) has been studied. The method was applied for determination of oxygen in 100 ml (∼ 90 g) rapeseed oil. The amount of oxygen in the rapeseed oil using the in-situ FNAA was estimated to 10.6 ± 2.6 weight %. Using cyclic fast neutron activation analysis (cFNAA), the amount of oxygen in the oil was determined in average 9.9 ± 0.4 weight %. Based on Monte Carlo calculations on water, the optimal radius and height of a cylindrical container where the activity is distributed through stirring of the water would be about 10 cm and 44 cm, respectively. These dimensions give a volume of about 14 liters, which is suitable for any type of oil. The accuracy in the in-situ FNAA can be increased by a more precise determination of oxygen in rapeseed oil in the beginning of a dynamic process using cFNAA or alternatively by a better background subtraction.
Investigation on bifurcation characteristics of a natural circulation system with low steam quality and low pressur
Authors: Jiang S. Y. , Yang X. T. , Zhang Y. J. 
Published: December 2013

AbstractThe two-phase flow is a kind of dissipative structure in multiphase hydrodynamics. A drift-flux model with four equations is adopted to investigate the natural circulation bifurcation, in which the sub-cooled boiling, condensation, and void fraction etc. have been taken into account. The bifurcation spectrum of a natural circulation system with low steam quality and low system pressure is presented and the physical mechanisms of bifurcation are described in detail. Bifurcation characteristics of the two-phase natural circulation indicate typical static instability observed in HRTL-5 simulating the geometry and system design of the 5 MW nuclear heating reactor operating at low steam quality and low system pressure. Analysis shows: (1) bifurcation phenomenon can occur in a two-phase natural circulation under certain thermal and geometrical condition; (2) with changing, namely increasing and decreasing, control parameters, the tracks of the work points of the natural circulation system are not identical, which shows the basic characteristic of the bifurcation phenomenon; (3) the bifurcation phenomenon of the natural circulation delay and disappear with increasing system pressure and decreasing heat flux.
Nitrogen transport in the primary circuit of a VVER during a LOCA occurring under plant cool-down conditions
Authors: Prasser H.-M. , Perneczky L. , Baranyai G. , Böttger A. , Ézsöl Gy. , Guba A. , Tóth I. , Zschau J. 
Published: December 2013

AbstractThe paper presents the results of a thermal hydraulic experiment conducted at the PMK-2 test facility within the IMPAM-VVER project. The test was dedicated to a loss-of-coolant event during the cool-down phase of the plant, when neither core flooding tanks nor safety injections systems are automatically available. Though fuel rod dryout occurs, the activation of one of four lines of low pressure emergency injection is sufficient to re-establish reliable core cooling. In the cooling-down situation, the primary circuit is pressurised with nitrogen, therefore, non-condensable gas can enter the primary circuit from the pressurizer during the blow-down phase. The transport of the nitrogen along the primary circuit was studied with a novel type of a local void probe equipped with an integrated micro-thermocouple. RELAP5 was found to be able to predict the behaviour of the non-condensable gas in the primary circuit. Despite of some delay in the prediction of the time of the appearance of the gaseous phase in the begin of the process, most details of the transient were well reproduced by the code.
Uncertainty and sensitivity analysis of void and power reactivity coefficients in an RBMK-1500 reactor core
Authors: Pabarcius R. , Tonkunas A. , Bubelis E. , Clemente M. 
Published: December 2013

AbstractUncertainty and sensitivity analyses were performed for the calculation of power and void reactivity coefficients of an RBMK-1500 reactor core state. Both parameters are important for the reactivity feedback behaviour and are of special safety relevance. The reactivity coefficients were calculated using the 3D-reactor core model QUABOX/CUBBOX-HYCA and the uncertainty and sensitivity analyses were performed by the GRS methodology applying the SUSA software package (Software System for Uncertainty and Sensitivity Analysis). A total number of 20 uncertain input parameters and their probability distributions were identified as possibly relevant for the size of the reactivity effects and taken into account in the SUSA analysis. The method helps to identify the main contributors to the uncertainty of calculated results, as well as to determine two-sided (95 %, 95 %) statistical tolerance intervals of the investigated reactivity coefficients. The approach to quantify uncertain parameters for RBMK-1500 core calculations using the SUSA code package and QUABOX/CUBBOX-HYCA was successfully performed. The results provide guidance where model improvements should be performed to increase the accuracy of the calculations efficiently.
Reactivity worth of the control rods at the ET-RR-2 reactor core
Authors: Saleh H. G. , Ashoub N. 
Published: December 2013

Abstract
Safety analysis of research reactors include a determination of control rod worth and kinetic parameters upon which the dynamic performance of the reactor depends. The core control of the ET-RR-2 reactor is accomplished through six Ag-In-Cd alloy-absorbing plates, which can be inserted into the core with a high velocity. In the present work, the fully and partially inserted control rod configuration in 3D reactor geometry and the effect of reactivity worth of the control rods on the reactor core is studied. The reactivity worth were calculated for each control rod and also for combinations of more than one rod. The total worth of all control rods in the reactor core is about 16.95% k/k from the core reactivity. Other neutronic parameters, i. e. the 3D neutron flux distribution and the change of the power peaking factor as a results of inserted and withdrawing the control rods were calculated.
Criticality analyses of regions containing uranium in the earth history
Authors: Ravnik M. , Jeraj R. 
Published: December 2013

Abstract
Investigations of necessary conditions for a self-sustained chain reaction in the Earth inner regions hypothetically containing uranium is presented for the time interval from Earth formation to present time. It is determined that criticality was theoretically possible up to 2.5 Ga before present if uranium concentrated in pure form. In the early geological history (4 Ga before present) the self-sustained criticality could occur even if uranium was diluted up to 1: 20 by the average core material or 1: 60 by the average mantle material. If other metallic materials of similar density as uranium (e. g., Au, W) or similar atomic weight (e. g., Th) concentrated from the primordial mixture in equal proportion as uranium, criticality was not possible for any period in Earth history provided that the basic material contained no light nuclides (H, C). Criticality in the Earth inner regions could have established only if uranium concentrated from the basic material more effectively than elements of similar density or atomic number.
Brennstabauslegung und Brennstabmodellierung – Teil 2
Authors: von Collani Elart , Baur Karl 
Published: December 2013

Abstract
Im Teil 1 dieser Untersuchungen wurde in das Problem der Brennstabauslegung eingeführt sowie die Grundlagen für das Verständnis des zweiten Teils gelegt. Dieser zweite Teil beschäftigt sich mit der mehr technischen Seite der mathematischen Modellierung des Verhaltens der Brennstäbe im Einsatz. Zusätzlich wird auf die in Deutschland aktuelle Diskussion über das sogenannte Ein-Brennstab-Quantil eingegangen.
The chemical separation of Eka-Hg from CERN W targets in view of recent relativistic calculations
Authors: Kolb D. , Marinov A. , Newton G. W. A. , Brandt R. 
Published: December 2013

Abstract
In 1971 evidence for the production of element 112 via secondary reactions in CERN W targets was obtained. The evidence was mainly based on the observation of fission fragments in Hg sources separated from the W targets, on the measured masses of the fissioning nuclei and on the assumption that element 112 (Eka-Hg) actually behaves like Hg in the chemical separation process. This assumption is analyzed in view of recent relativistic calculations of the electronic structure of element 112. It is shown that in the superheavy element region only the chemistry of element 112 is similar to that of Hg.