bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multi-Level Porosity Silver Foams by Powder Processing Method
Authors: Preuksarattanawut Thanachache , Nisaratanaporn Ekasit , Asavavisithchai Seksak 
Published: December 2013

Abstract
Silver foams with 70% porosity have been produced by the sintering and dissolution process (SDP) of fine silver powder. The powder was obtained from the reduction of rod-shaped silver sulfate, using glycerol mixed with sodium hydroxide as reducer and reaction accelerator, respectively. The foam shows three-level porosities, ranging from nanometer to millimeter level. The nanopores were created during the reduction process. The micropores were formed by the dissolution of remaining silver sulfate. The millipores were made from the removal of disaccharide powders. The pore architecture is unique and can be tailored by varying material and process parameters such as silver sulfate and disaccharide morphologies, reduction temperature and time as well as volume fraction of materials.
Use of Grey-Taguchi Method for the Optimization of Oblique Turning Process of AZ91D Magnesium Alloy
Authors: Buldum Bariş , Eşme Uğur , Kemal Külekci Mustafa , Şik Aydin , Kazançoğlu Yiğit 
Published: December 2013

Abstract
This study investigated the multi-response optimization of turning process for an optimal parametric combination to yield minimum cutting forces and surface roughness with maximum material removal rate (MRR) using the combination of Grey relational analysis (GRA) and Taguchi method. Nine experimental runs based on an orthogonal array of Taguchi method were performed to derive objective functions to be optimized within experimental domain. The objective functions have been selected in relation to parameters of cutting process: cutting force, surface roughness and MRR. The Taguchi approach followed by Grey relational analysis to solve the multi-response optimization problem. The significance of factors on overall quality characteristics of the cutting process has also been evaluated quantitatively by the analysis of variance method (ANOVA). Optimal results have been verified through additional experiments. This shows proper selection of the cutting parameters produces, high material removal rate with better surface roughness and lower cutting force.
A New Design of Hip Prosthesis Coating using Functionally Graded Material
Authors: Hedia Hassan S. , Fouda Noha 
Published: December 2013

Abstract
Titanium and its alloys which have been widely used in many prostheses carry the major joint load and cause stress shielding. Thus, the bone might become osteoporotic due to lack of physiological stress flow in common hip replacement. Therefore, the optimization of hip joint materials is one of the most challenging tasks in prosthetic design. It is found in the literature that there is a great contradiction regarding the use of hydroxyapatite (HAP) coating. In this study a finite element analysis (FEA) and optimization techniques have been carried out in order to find a new design of hip stem coating using functionally graded material (FGM) to reduce stress shielding at the proximal medial part of the femur, as well as reducing the interface shear stress at the interface between the coating and the bone which directly affects the implantation and long-term stability. This work is divided into two parts: in the first part, the gradation of the elastic modulus of the coating material has been changed in the vertical direction, while the second part changes the elastic modulus in the horizontal direction. The optimal design of the first and second models was compared with HAP coating and with homogenous uncoated titanium stem. The design optimization of the first model revealed, using a coating material consisting of HAP at the upper layer of the coating graded to collagen at the lower layer, increases the maximum von Mises stress in bone at the proximal medial part of the femur by 65% and 19% compared to titanium stem and titanium coated with HAP, respectively. The maximum lateral interface shear stress in the bone at the bone/coating interface is reduced by 23% and 12%, respectively. However, the maximum medial interface shear stress in the bone at the bone/coating interface is reduced by 39% and 14% compared to titanium stem and titanium coated with HAP, respectively. The design optimization of the second model revealed, using a coating material consisting of collagen at the inner layer adjacent to stem graded to HAP at the outer layer adjacent to bone, increases the maximum von Mises stress at the proximal medial part of the femur by 60% and 15% compared to titanium stem and titanium coated with HAP, respectively. The maximum lateral interface shear stress is reduced by 18% and 6%, respectively. However, the maximum medial interface shear stress is reduced by 35% and 8% compared to titanium stem and titanium coated with HAP, respectively.
Influence of Deformation on the Phase Structure of a 30CrMnSi Steel
Authors: Skakov Mazhyn , Uazyrkhanova Gulzhaz , Popova Natalya , Scheffler Michael 
Published: December 2013

Abstract
The grainary substructure of 30CrMnSi steel has been studied after rolling deformation. It has been found that in the studied material the bulk share of anisotropic grains amounts to 25% and the isotropic grains to 75%. It has been observed that the martensitic structure is completely broken in the rolling process.
Electrolytic Recovery of Tin from Waste Lead Frames: Use of Aqueous HCl Leaching Solution as Electrolyte
Authors: Kang Kyung-Hoon , Kim Beomseok , Seo Min Hye , Cho Sung-Su , Lee Sungkyu , Hong Hyun Seon 
Published: December 2013

Abstract
Lead frames are generated in large quantities by modern semiconductor packaging industry and they contain significant concentrations of valuable tin, nickel, and copper. For electrowinning of tin from waste lead frames, hydrochloric acid leaching of tin is quite advantageous, but solution stability, electrolytic efficiency and deposit morphology should be optimized before commercialization. HCl electrolyte was diluted (distilled water: HCl = 350:150) for electrowinning of waste lead frames at 40 °C with 0.2 A/cm2 and Ti-Ir cathode. After 4 h electrowinning, 99% pure Sn with 99.1% recovery rate was produced. Therefore, aqueous HCl electrolyte was quite effective for electrowinning of Sn leaching solution, and a higher recovery rate of purer Sn within shorter electrowinning time was obtained.
Statistical Interactions in Phosphate Rock Calcination
Authors: Al-Fariss T.F. , Abd El-Aleem F.A. , El-Midany A.A. 
Published: December 2013

AbstractMost of the marine phosphate deposits are calcareous phosphates. Calcination process is one of the famous processes used for upgrading sedimentary calcareous phosphate ore. In this study, evaluation of the calcination process performance in terms of its operating parameters was carried out. The effect of operating parameters and their significance on calcination of calcite as a main phosphate ore impurity was studied using statistical design of experiments. A statistical model was developed to correlate the studied parameters with the phosphate grade in the calcined product. The studied parameters were temperature, time, and particle size. The analysis of the design results showed that the tempe­rature is the most significant parameter. The higher the temperature is the higher the calcite conversion to calcium oxide and release of carbon dioxide. In addition, the particle size plays a significant role in contact area between particles as well as the voids among them that help to release the CO2faster. Moreover, a phosphate concentrate, suitable for phosphoric acid production, containing ∼32 % P2O5can be achieved at optimum values of studied parameters, i. e., at a temperature of 850 °C, after a calculation time of 40 minutes and with a particle size of 0.074 mm, respectively. Furthermore, quenching and slacking of calcined products increased the grade by 2–3 % to reach 34 % to 35 % P2O5in the final concentrate.
Einfluss der Verformungsgeschwindigkeit und des Feuchtegehaltes auf das quasistatische Verformungsverhalten technischer Vulkanfiber∗
Authors: Penning Bastian , Walther Frank , Dumke Dominik , Künne Bernd 
Published: December 2013

Abstract
Ein detailliertes Wissen über die Werkstoffeigenschaften stellt für Konstrukteure und Fertigungsingenieure die Grundvoraussetzung zur Gewährleistung eines sicheren und wirtschaftlichen Betriebs von Bauteilen dar. Ziel dieser Untersuchung ist es, den nur wenig untersuchten Konstruktionswerkstoff Vulkanfiber hinsichtlich des Einflusses der Verformungsgeschwindigkeit und des Feuchtegehaltes auf die quasistatischen Eigenschaften mikrostrukturbasiert zu charakterisieren und zu bewerten. Neben materialografischen und mikroskopischen Einrichtungen wurden ein Ultramikrohärteprüfsystem sowie zur mechanischen Charakterisierung eine elektromechanische Universalprüfmaschine, ein taktiles und ein Videoextensometer, Thermoelemente und ein Thermografiesystem sowie eine Hochgeschwindigkeitskamera zur Detektierung des Rissbildungs- und -ausbreitungsverhaltens eingesetzt.
Evaluation of Geometric Accuracy and Thickness Variation in Incremental Sheet Forming Process
Authors: Durgun Ismail 
Published: December 2013

Abstract
The aim of this study is to evaluate dimensional conformity and thickness variation of a pyramid geometry obtained by negative single point incremental sheet forming. DC04 mild steel, which has been widely used in automotive and numerous applications due to high formability, was used for experimental investigations. Dimensional accuracy of whole geometry and surface roughness are investigated under the influence of toolpath parameters such as tool diameter, feed rate and vertical step down. In this paper, geometric accuracy and thickness are evaluated by production tolerances of conventional methods and results show that thickness reduction of formed sheet and geometrical deviation of side faces are out of tolerance for all cases.
Effect of Plasma Nitriding Parameters on the Wear Behaviour of AISI D6 Tool Steel
Authors: Korkmaz Ersin Eser , Bayram Ali , Ertan Rukiye , Yavuz Nurettin 
Published: December 2013

Abstract
In the present investigation, the effects of plasma nitriding pressure and time on the structural and tribological characterization of AISI D6 grade cold work tool steel were studied. DC glow discharge plasma nitriding process under NH3 gas was performed at temperatures of 500 °C and at pressures of 150 Pa, 450 Pa and 800 Pa for durations of 2 h, 7 h and 10 h. The mass loss and the coefficient of friction were measured using a ball-on-disc wear test with 1.668 N, 4.143 N, and 9.113 N test loads. Cross-section and surface characterizations were evaluated using optical microscopy, SEM, and microhardness test techniques. The surface microhardness was found to increase with the nitriding time and the pressure. The wear resistance of the specimen strongly depends on the nitriding parameters and the applied test load in determining whether a plastic deformation of the surface layer has occurred or not.
Investigation of Modal Properties of AlSi7 Foam Produced by Powder Metallurgy Technique
Authors: Uzun Arif , Gökmen Uğur , Cinici Hanifi , Koruk Hasan , Turker Mehmet 
Published: December 2013

Abstract
The modal properties of aluminum-based (AlSi7) metallic foam, produced by powder metallurgy technique, as a function of foam density (and thus pore size and amount of porosity) were investigated. In the experimental studies, 1 wt.-% TiH2 and 7 wt.-% Si powders were added to aluminum powder and they were mixed in a three dimensional turbola mixer for 30 minutes. Mixed powders were compacted, extruded and rolled to produce the precursor samples. AlSi7 foam samples with the dimensions of 18.7 cm × 2.6 cm × 1.6 cm were produced after foaming at 690 °C. After all, the natural frequencies and the modal loss factors of a few foam samples with different pore distributions and/or densities were determined using the frequency response functions measured on the test samples. The results show that the densities of the foam samples decrease with increasing pore size and amount of porosity, and the modal loss factors of foam samples increase as foam density decreases.
“Vertical Dimensions” of Pulsed Laser Welding
Authors: Çelen Serap , Karadeniz Süleyman 
Published: December 2013

Abstract
Laser welding, perhaps the most prominent tool for modern manufacturing systems, enable the performance of safe and sound weldments with operational reliability. Thus, the use of lasers provides economical efficiency via quantitative increase of production with quality improvement, and shortening the required welding process time. Laser welding can readily be used at pulsed and continuous mode with assisted systems. It may be time for a paradigm shift and for an exploration of new viewpoints with regarding its distinctive features. In the present investigation, we go beyond current classical approach by presenting novel features of laser welding included in these experiments. Thus, the purpose of this manuscript is to consolidate a proposal for reducing the time for pulsed laser welding with a novel design approach which can be called “vertical dimensions”. This method can facilitate the human processes of making decisions for setting unknown parameters and shorten their process time by actively reducing operations with creating a unique approach. We characterize our resultant weld morphology of laser welds as a function of these vertical dimensions.
Simple formulas for conservatively calculating the fuel rod cladding strains due to RIA
Authors: Sauer G. 
Published: December 2013

Abstract
A set of formulas for conservatively computing the fuel rod cladding strains caused by short and intense energy pulses is presented. Such pulses may be the consequence of a RIA. The formulas are based on the theory of stresses and deformations of tubes loaded by internal pressure and stressed beyond the elastic limit. The known solutions of this theory are applied to compute the cladding strains due to the intense interaction between fuel and cladding during a RIA. Simple and easy to evaluate expressions for the strains are obtained. They enable to quickly assess the impact of any energy pulse for any burn-up state. The actual burn-up state of the fuel rod at the moment in which the occurrence of a RIA shall be simulated is described by only three data. These data can be calculated in an enveloping sense in advance and then be used to study energy pulses of any intensity. Besides the cladding strains induced by the fuel-cladding interaction the significance of the gas pressure in the rod and of gas swelling for the cladding strains is also addressed.
The time-dependent effect of the biological component of 137Cs soil contamination
Authors: Dederichs H. , Pillath J. , Lennartz R. , Hill P. , Hille R. 
Published: December 2013

Abstract
In investigations of the long-term development of the population dose in the highly contaminated regions of the Commonwealth of Independence States it was found that the external dose has not decreased as strongly as expected since 1992. Further investigations have shown that, contrary to expectations, no linear correlation can be observed between soil contamination and measured area dose rate. As a contribution towards clarifying these issues, the area dose rate and the soil contamination including the plant fraction were investigated in the Korma district, Belarus. It was found that it is necessary to cover and average over larger areas in order to determine from ground contamination the long-term development of the external dose commitment. This means that for this purpose the introduction of an “effective” surface contamination (sum of mineral and organic contamination components) is necessary. The phenomena observed are described in a model, which permits an analytical calculation of the contamination profile in soil taking migration and transfer effects into account. The differences observed between the measured soil contamination and the resulting external doses or the directly measured dose rate can be explained by the proposed model. Moreover, their long-term development can be calculated. The results show that a time decade after the accident the biological part of the “effective” soil contamination becomes dominant and cannot be neglected.
Calculation of the energy deposition in the targets from C to U irradiated with intermediate energy protons
Authors: Broeders C. H. M. , Konobeyev A. Yu. , Travleev A. A. 
Published: December 2013

AbstractThe energy deposition was calculated for the targets from carbon to uranium irradiated with intermediate energy protons with the help of different models incorporated in the MCNPX code package (Bertini, CEM and ISABEL) and with the help of the CASCADE/INPE code. The values obtained using the different models and codes are in a good agreement for all targets except uranium. The comparison with the available experimental data for the heat deposition for 0.8, 1.0 and 1.2 GeV protons has been performed. The good agreement is observed for copper, lead and bismuth target. The best result is obtained with the help of the ISABEL model. The systematic dependence of the heat deposition from atomic number of the target was investigated. The contribution of different particles and energy ranges in the heat deposition has been studied at the primary proton energies from 0.3 to 2.5 GeV.
U-Pb accelerator-driven sub-critical systems research at the proton beam of the JINR NUCLOTRON
Authors: Barashenkov V. S. , Kumawat H. 
Published: December 2013

AbstractNeutron spectra, yields and energies of particles generated by a uranium electro-nuclear set-up which is now used in Dubna for transmutation research of various isotopes with a proton beam of an energy of 1–2 GeV, were analyzed by means of mathematical modelling based on the Monte Carlo code CASCADE. The influence of space dispersion on the proton beam and its possible deviation from the center of a lead target is investigated. It is shown that the polyethylene radiation shielding that is being used now, does not protect the measuring room from neutrons and γ-rays.
Monitoring and prediction of the dispersion of radioactive substances in German Federal waterways – concepts and methods
Authors: Dersch G. , Krause W. J. 
Published: December 2013

Abstract
Based on the Precautionary Radiation Protection Act, the Federal Institute of Hydrology (BfG) is the Federal Center for the monitoring of radioactivity of the German Federal Waterways. In this function, the Institute operates a Radioactivity Measuring and Sampling Network along the Federal Waterways. Priority monitoring tasks are the early warning, the determination of radionuclides in water, suspended solids and sediment (laboratory measurements) and the prediction of dispersion by means of dispersion investigations using tritium as a tracer. This report gives a survey on the present status of the concept and the methods used, as well as an outlook on their further development.
Combination of measurements and model predictions after a release of radionuclides
Authors: Gering F. , Richter K. , Müller H. 
Published: December 2013

Abstract
Model predictions for rapid assessment and prognosis of possible radiological consequences after an accidental release of radionuclides play an important role in nuclear emergency management. Radiological measurements (e. g., dose rate measurements, contamination measurements of foodstuffs) can be used to improve such model predictions. This paper describes a method for combining model predictions and measurements (data assimilation) in the deposition model and the food chain model of the European radiological decision support system RODOS. The data assimilation approach is based on the Ensemble Kalman Filter, a Monte Carlo variant of the Kalman filter.
German assistance for the dismantling of nuclear submarines in Russia
Authors: Hinsdorf H.-J. 
Published: December 2013

Abstract
On October 9, 2003, the German Ministry of Economics and Labor signed an agreement with the Russian Federation's former Ministry of Atomic Energy for support in eliminating the nuclear weapons that the Russian Federation has pledged to reduce through the dismantlement of decommissioned nuclear submarines. This treaty, which is binding under international law, implements the Global Partnership against the Spread of Weapons and Materials of Mass Destruction as agreed to at the G8 Summit in Kananaskis in 2002. The core element of the German-Russian project is the creation of a long-term interim storage facility for 120 nuclear submarine reactor compartments near Murmansk in northwestern Russia and the preparation of the reactor compartments for interim storage. This technically demanding project, which began not without some problems, has developed in a positive manner since the end of 2003. The provisions in the treaty and its supplementary documents, which were internationally publicized, have generally proven to be successful.
Semi-statistical mechanical fuel rod design
Authors: Sauer G. 
Published: December 2013

Abstract
A technique to combine statistical and deterministic approaches in mechanical fuel rod analysis is described. The impact of different fuel rod input parameters on the fuel rod design parameter under consideration is identified by statistical means. It is expressed through rank correlation coefficients. These coefficients are then employed to calculate corresponding quantiles for the input parameters allowing the selection of appropriate input values from the parameter probability distributions. The quantiles are computed with the provision that the fuel rod reactions obtained with the associated input parameter combination cover the reactions in a subset of the analysed fuel rod totality. The described procedure reduces the computational costs in comparison to some pure statistical methods of fuel rod design.
Fire hazard analysis at Ignalina Nuclear Power Plant
Authors: Poskas P. , Simonis V. , Zujus R. , Kilda R. , Sirvydas A. , Kolesnikovas J. 
Published: December 2013

Abstract
The fire hazard analysis methodology and main results of Ignalina Nuclear Power Plant RBMK-1500 type reactor's systems and rooms with safety elements and also rooms adjacent to main rooms and other fire hazardous rooms are presented. In total this concerns about 2100 rooms in the control area of one Unit, where the fire could influence nuclear safety of the power plant. For this purpose the decision-making computerized system FIRE-INPP was developed. It includes modules for recording necessary information, data processing, analysis and assessment on compliance of rooms at Ignalina NPP with national fire safety requirements and international recommendations regarding fire hazard. Screening algorithms and decision-making module are the basis for the decision-making computerized system, that allows to perform unambiguous, reliable and fast fire hazard analysis and give recommendations to ensure fire safety adequacy.
On the plane-wave theory in fertile uranium
Authors: Seifritz W. 
Published: December 2013

AbstractThe theory of the autocatalytic burn-wave phenomenon in fertile material for a 1D solitary plane-wave is summerized together with a variety of analytical approximations. It was found that the modified logarithmic product approximates best the fluence- and neutron flux shapes including their skewness – being absolutely necessary for a propagating burn-up wave. Due to the stability of these shapes they propagate isentropically: The deeper reason why we could harness the breeding principle without reprocessing.