bluuebunny/crossref_metadata_2025 huggingface dataset:
Changes in Grafted Autogenous Bone during Edgewise Treatment in Patients with Unilateral Cleft Lip/Palate or Alveolus
Authors: Maeda Aya , Uehara Sawako , Suga Mayu , Nishihara Kazuhide , Nakamura Norifumi , Miyawaki Shouichi
Published: September 2013

Objective

To examine the changes in autogenous bone from 6 to 12 months after alveolar bone grafting (ABG) (T1) through completion of edgewise treatment (T2).

Design

Retrospective longitudinal study.

Setting

Multidisciplinary long-term follow-up at Kagoshima University Hospital.

Patients

Forty-three patients with unilateral cleft lip and palate or alveolus.

Main Outcome Measures

At T1 and T2, the bone bridge and quantity of grafted bone were evaluated using the Chelsea scale and the ABG scale. The cleft-adjacent tooth angles before ABG and at T2, as well as the number of orthodontic space closures, were examined. Patients were classified as having either adequate (type A or C; adequate group) or poor bone bridges (type B, D, E, or F; poor group) by the assessment at T1.

Results

At T1, the ABG scores for the cleft-adjacent central incisor side of patients in the adequate group were higher than those of patients in the poor group ( P < .001). At T2, the adequate group had higher ABG scores for the cleft-adjacent central incisor side ( P = .022) and the canine sides ( P = .034). No significant differences in tooth angles or the number of orthodontic space closures were noted between the groups.

Conclusions

These results suggest that the quantity of grafted bone in the cleft-adjacent central incisor at 6 to 12 months post-ABG may be an indicator of the quantity of grafted bone that will be present after edgewise treatment.
Artificial pozzolana from silica gel waste–clay–limestone composite
Authors: Kaminskas Rimvydas , Kubiliute Raimonda
Published: September 2013

This study investigated the possibility of using artificial materials obtained during combustion of silica gel–clay–limestone composites as a pozzolanic additive for Portland cement. The granules of the composites investigated were formed from dried components that were later wetted. The granules thus obtained were burned at 700°C for 1 h. In the samples, 5, 15 and 25% (by weight) of the Portland cement was replaced with the additive. The specimens were then hardened for 28 days under normal conditions. It was estimated that combustion of silica gel–clay–limestone composite at 700°C produced a new artificial pozzolana (SGCL), the pozzolanic activity of which is 260 mgCaO/g. During the combustion process, the fluorine from silica gel was not released into the atmosphere, but combined to form a stable CaF2 compound. It was established that 5 and 15 wt% SGCL pozzolana additive increased the compressive strength of the samples that were cured for 7 and 28 days under normal conditions. This effect is related to the on-going pozzolanic reaction and the formation of stratlingite (C2ASH8) and hydrogarnet (C3ASxH6–2x). It was estimated that CaF2, which was formed during combustion of the SGCL composite, remained in a stable form during the curing process of the samples. This was because all investigated samples of cement with different amounts of additive released a negligible quantity of fluorine (<1·5 ppm) into the liquid phase.
Briefing: Blast effects on biological systems
Authors: Masouros Spyros D. , Brown Katherine A. , Clasper Jon , Proud William G.
Published: September 2013

A signature of current conflicts is the use of buried improvised explosive devices to cause injury to military personnel and damage to their vehicles. Explosive devices also cause injuries to non-military populations in current and former conflict zones. The nature and placement of the explosive charge has a marked effect on the loading experienced. In all situations, damage to tissues occurs when the energy and loading rate exceeds that which the human body can support. Currently, it is difficult to predict the various time-dependent effects of blast injury because of the complexities of the rapid initial accelerations, the loading geometries and the heterogeneous nature of the tissues that can be damaged. An outline of the ways in which one may study how explosive energy interacts with biological systems is presented along with a discussion of how the data generated can be used to develop improved, cost-effective strategies for studying blast injury processes.
Sea level variation from a remote river in the Gulf of Paria, Trinidad
Authors: Subrath-Ali Carol , Chadwick Andrew J. , Dialsingh Isaac , Sahai Ashok
Published: September 2013

Short-term sea level variability is investigated by analytical methods to ascertain whether there is a link between peak tidal residuals in the Gulf of Paria (GoP), Trinidad, and peak river outflow from the Orinoco on the Venezuelan mainland. Analysis of tidal data suggests that although the Orinoco delta fronts the Atlantic ocean, significant volumes of this river runoff enter into the GoP and play a role in seasonal sea level variation on the western coastline of the southernmost Caribbean island of Trinidad. The indications from various statistical analyses including harmonic, spectral and time series analyses of tide gauge data are that mean seasonal variations in water level in the north of the GoP exhibit a positive temporal correlation between the tidal residuals and the peak river discharge associated with the Orinoco's seasonal cycle. The maximal de-tided residuals are strongly correlated with maximal values of the river runoff, as well as the discharge trend, with the residual values at initial average estimates of about 12–15 cm/year.
The distribution and host range of Batrachochytrium dendrobatidis in New Zealand, 1930–2010
Authors: Shaw Stephanie D. , Skerratt Lee F. , Haigh Amanada , Bell Ben D. , Daglish Lisa , Bishop Phillip J. , Summers Rachel , Moreno Virginia , Melzer Sabine , Ohmer Michel , Herbert Sarah , Gleeson Dianne , Rowe Lucy , Speare Richard
Published: September 2013

Chytridiomycosis caused by the fungal invasive pathogen Batrachochytrium dendrobatidis (Bd) was first detected in 1999 in Christchurch, New Zealand, in the Australian introduced frog species Litoria raniformis. It was detected in wild native frogs in the critically endangered Leiopelma archeyi in 2001 on the Coromandel Peninsula and has been suggested as responsible for a mass decline (88%) in that population between 1994 and 2002. We report the current distribution, host species and prevalence, where known, of Bd in New Zealand, which is essential for conservation management of New Zealand native frogs (Leiopelma spp.). The data set is structured so that it can be readily added to the Australian Bd database for further analyses. Our data included all regions in New Zealand and six offshore islands at 135 sites with 704 records from 23 contributors spanning collection dates 1930–2010. We report 54 positive sites from 132 positive individuals. We also detail negative findings, but declaring an area free from disease should consider the sensitivity of the test used and numbers of individuals tested. The data also included a comprehensive museum survey testing 152 individuals from five species (20 L. archeyi, 50 L. hochstetteri, 15 L. aurea, 40 L. ewingii, and 27 L. raniformis) from 1930–1999 using histology and Bd‐specific immunohistochemistry. All museum specimens were negative, so the 1999 positive result is still the earliest record. In the L. archeyi Coromandel Ranges population, the period prevalence of Bd from 2006 to 2010 was relatively stable at 16%, but the number of animals tested remains low (up to N = 19) due to the now depleted population numbers. The period prevalence of Bd in the L. archeyi Whareorino population has remained both consistent and low (6%) between 2005 and 2010. In L. hochstetteri, L. hamiltoni, and L. pakeka all sampling for Bd has been negative. Positive Bd results have been found in all three Litoria spp., but Bd has not been found in the six offshore areas tested. Most data have been previously unpublished and represent the first confirmed reports of Bd in many regions and species in New Zealand.
Half a century (1954–2009) of dissection data of sea urchins from the North American Pacific coast (Mexico–Canada)
Authors: Ebert T. A. , Hernández J. C. , Clemente S. , Russell M. P. , Basch L. V. , Boolootian R. A. , Detwiler P. M. , Kenner M. C. , Lawrence A. L. , Lawrence J. M. , Leighton D. L. , Palleiro J. S. , Pearse J. S.
Published: September 2013

Total body size, mass or linear measurements, and gonad mass or volumes have been recorded for the North American Pacific coast sea urchins Strongylocentrotus purpuratus, Mesocentrotus (Strongylocentrotus) franciscanus, and Lytechinus pictus by various workers at diverse sites and for varying lengths of time from 1954 to 2009. Some dissections included other body components such as the gut, body wall, and Aristotle's lantern, and some dissections included both wet and dry mass. There are numerous peer‐reviewed publications that have used some of these data, but some data have appeared only in graduate theses or in the gray literature. There also are data that have never appeared outside the original data sheets. Historically, data were used to describe reproductive cycles and then to compare responses to stressors such as food limitation or pollution. Differences in temperature among sites also have been explored. More recently, dissection data have linked gonad development to ocean conditions, so called bottom‐up forcing. The data set presented here is a historical record of gonad development for a common group of marine invertebrates in intertidal and nearshore environments, which can be used to test hypotheses concerning future changes associated with climate change and ocean acidification along the Pacific Coast of North America.
Applying online UV/Vis-spectrometry for process control of an ozonation step for advanced wastewater treatment
Authors: Schaar H. , Kornfeind L. , Winkler S. , Saracevic E. , Kreuzinger N.
Published: September 2013

The ozonation of tertiary effluent for advanced wastewater treatment requires a comprehensive control strategy in order to guarantee stable, efficient and economic operation. In the present study the dissolved organic carbon (DOC) in the influent to the ozonation plant was selected as key control parameter and residual ozone in the effluent was included as a secondary control. The objective was to evaluate UV/Vis (ultraviolet-visible)-spectrometry for the calculation of equivalent concentrations for the control parameters DOC and ozone using cross-validated PLSR models. The results of the DOC model were in good agreement with the laboratory reference data. Eighty percent of the validation data had a relative error below 10%, while the mean relative error was 1.5%. Despite the interference of the organic matrix with ozone in the UV-range an independent ozone model was developed achieving a mean relative error of 5.6%. Based on the results obtained in this study, the novel approach of using UV/Vis-spectrometry for process control of effluent ozonation proved to have a high potential for practical application.
Anaerobic digestion of sewage sludge: overview of the French situation
Authors: Reverdy A. L. , Dieudé-Fauvel E. , Ferstler V. , Baudez J. C.
Published: September 2013

Following the French environmental national debate, called ‘Grenelle de l'Environnement’ and according to the Kyoto Protocol, France looks at increasing its production of renewable energies, among them biogas production from organic wastes and more specifically from sewage sludge.

A quick survey of official data shows that in 2009, sludge biogas only represented 0.93% of the total renewable electricity production, far from the situation in the neighbourhood countries.

To understand this situation, this article aims at inventorying sludge anaerobic digestion process, in Europe then more precisely in France. The different technologies used to perform anaerobic digestion process have been investigated, including the type of waste, pre-treatments, digester specificities, mixing and heating systems.

In France, a survey has been realised to determine the situation for wastewater treatments plants bigger than 30,000 equivalent inhabitants. Mesophilic digestion in a constantly mixed reactor is mainly used. Moreover, some plants have given specific details about the cost of the process or its efficiency. These results are discussed.
A new approach for reducing diffuse agricultural pollution in water supply ponds
Authors: Berne André
Published: September 2013

Preserving the quality of raw water for drinking likely to be affected by diffuse pollution in water supply ponds (WSPs) is a major public health issue.

We must therefore implement efficient and sustainable technical measures that guarantee the long-term protection of this resource. Such measures can prove to be a considerable constraint for farm managers and farm owners. It is consequently absolutely necessary that the compensation provided for is in line with these constraints. High stakes and high constraints must result in high compensation. The catchment protection perimeter tool, reviewed and enlarged to encompass up to 100% of the WSP, renewed and in-depth dialogue based on solid technical and economic studies and a new compensation method established from the principle of discounted loss capitalisation over a duration equal to the lease, are all new and promising tools to solve this essential problem for sustainable development throughout the territory and to preserve the health of its population.
Production and utilization of cassava peel activated carbon in treatment of effluent from cassava processing industry
Authors: Omotosho O. A. , Sangodoyin A. Y
Published: September 2013

Industrial waste disposal is a worldwide problem. It is necessary to manage production facilities and systems properly to prevent environmental degradation. The major aim of this study was to produce Zinc Chloride activated carbon from cassava peels which is a major solid waste from the cassava production process. The wastewater from cassava processing was treated using a peroxide oxidation process before being subjected to adsorption using Cassava Peel Activated Carbon (CPAC) at different activation levels. Results from the study shows that CPAC at activation ratio of 1:1 was the most effective as all parameters after adsorption with the exception of suspended solids fell below FEPA interim standard on discharge. The CPAC at 2:3 activation ratio also met the discharge standards but after 8 hrs of contact time. The result shows that CPAC could be adopted for treatment of cassava industry wastewater. Decontamination efficiency of the CPAC was 100% for Ni, Cd, Cr and CN at all activation levels while BOD5 removal for no activation, 1:3, 2:3, 1:1 ZnCl2 activation levels were 78.8, 85.9, 87.9 and 92.9% respectively. The CPAC exhibited the lowest values for Ca removal efficiency of 8.9, 8.9, 10.1 and 10.1% for no activation, 1:3, 2:3 and 1:1 activation levels respectively. Colour removal efficiency values were 33.3, 41.7, 41.7 and 50.0% respectively after 8 hrs of contact time.
Evaluation of environmental pollution effects on domestic roof-harvested rainwater in Southern part of Nigeria using impact indices
Authors: Akintola O. A. , Sangodoyin A. Y. , Agunbiade F. O.
Published: September 2013

The effects of environmental factors, roof materials and age of roof on some metals usually found in Domestic Roof-Harvested Rainwater (DRHRW) from southern Nigeria were investigated. Samples were collected in Ibadan (residential), Lagos (industrial) and Port-Harcourt (gas-flaring). Four roof types (corrugated-iron-sheet, long-span-aluminium, asbestos and step-tiles) and three ages of roof (<5, 5–10 and >10 years in service conditions) were considered. Sample preparations, handling and analysis were carried out using standard procedures. Enrichment-Factor, Transfer-Factor and Pollution-Load-Index were estimated to identify roof polluting severity, rate of transfer of each metal detected into the DRHRW as well as atmospheric contribution to the overall pollution effects observed. Metal enrichment was generally low indicating low metal transfer into DRHRW from the sites. Occasional moderate enrichment was recorded for Fe, Cu, Zn, Ca and Mg suggesting their natural presence in the environment. Extremely high enrichment observed for Pb and Cd in industrial and gas-flaring rainwater samples as compared with residential indicated that metal contaminations in these locations are higher compared to residential samples which serve as background. Rate of metal transfer from roof material to rainwater was generally low. Thus, the possible source of the metal contaminants found in DRHRW in the areas investigated was the atmosphere. Mean Pollution-Load-Index of 0.95, 0.99 and 1.06 for rainwater samples in Ibadan, Lagos and Port-Harcourt areas respectively suggested higher pollution load in gas-flaring than residential and industrial regions. Pollution-Load-Index applied to age and roof-type indicated that long-span-aluminium and asbestos roofs that are less than 5 years could contaminate rainwater.
Proximal Humeral Fractures: A Review of Current Concepts
Authors: Widnall James C. , Dheerendra Sujay K. , Malal Joby Jacob George , Waseem Mohammed
Published: September 2013

The majority of proximal humerus fractures are sustained via low energy falls in the elderly population. These patients can attain an acceptable level of function via non-operative treatment. There is yet to be a clear consensus on treatment options suitable for those that fall outside of this majority group. Open reduction internal fixation, intra medullary nailing and arthroplasty surgery have all been used to varying effects. Good results are achievable if complications such as mal-union, non-union and avascular necrosis can be avoided. This review aims to clarify the options available to the current day trauma surgeon.
Modularization in the Construction Industry Using a Top-Down Approach
Authors: Kudsk Anders , Hvam Lars , Thuesen Christian , O'Brien Gronvold Martin , Holo Olsen Magnus
Published: September 2013

Throughout the last centuries, the manufacturing industry has experienced great improvements in efficiency
and cost reductions, but the same improvements have not taken place in the construction industry. Based on the principles
of mass customization that are known from the manufacturing industry, a case study of one of the largest construction
companies in Northern Europe was carried out according to the principles of action research. This approach was used to
clarify whether potential exists for using the principles of mass customization to improve efficiency and minimize costs
connected with the construction of buildings; and if so, what they are. The main technical solutions used for residential
and office buildings were analyzed using a top-down approach. These solutions were identified and their relations mapped
using a Product Variant Master (PVM). When a satisfactory overview was achieved of the major technical solutions, a
configuration system was made. Such a system is often used to communicate findings from the PVM to the user. Through
the work of constructing the PVM and the configuration system, it was found that a great potential exists for implementation.
Based on the findings and experiences gathered throughout the process, the conclusion is that the principles of mass
customization are best used in the construction industry if used with a top-down perspective.
Magnetic Properties of Co-Fe Nanowires Electrodeposited in Pores of Alumina Membrane
Authors: Dobosz I. , Gumowska W. , Czapkiewicz M.
Published: September 2013

The nanowires of Co66-Fe34 alloy were obtained in the process of the electrodeposition in the pores of alumina membrane. With the use of the X-ray diffraction analysis the structure of cobalt-iron alloy wires was determined. The wires have the regular Body Centred Cubic structure (BCC). The influence of membrane parameters, an external magnetic field, and the annealing temperature on the magnetic properties of alloy wires was investigated. The obtained nanowires show a high shape anisotropy in the direction perpendicular to the membrane surface of anodic alumina. It was found that the highest influence on the magnetic properties of the wires has their geometry (height, diameter, and the distance between them). The use of an external magnetic field directed perpendicular to the sample surface during the electrodeposition process and additional thermal treatment (annealing) causes a slight increase of the coercive field, remanence, and volume energy density.
Residual Stress Analysis of Insulation Coatings for Magnet Technologies
Authors: Guney D.
Published: September 2013

High temperature MgO-ZrO2 insulation coatings were grown on long-length Stainless-Steel (SS) tapes by reel-to-reel sol-gel method for applications of High Temperature Superconductor/Low Temperature Superconductor (HTS/LTS) coils and magnets. The residual stresses were investigated analytically at various temperature ranges, 580°C to 25°C (room temperature) and -196°C (liquid helium temperature), and 630°C to 25°C and -196°C for different thicknesses to be 13, 12, and 7 μm. The maximum stress values were obtained to be 1.92 GPa in tension for SS substrate with the 13 μm coating and -2.42 GPa in compression for the 7 μm MgO-ZrO2 coating in the temperature range between 630°C and liquid helium temperature. The surface morphologies and microstructure of sample were also characterized using a scanning electron microscope (SEM). SEM observations revealed that MgO-ZrO2 coatings have a mosaic like crack structure.
Analysis of Problems Occured During Welding of New Genreation Bainitic Steel 7CrMoVTiB10-10 (T24)
Authors: Urzynicok M. , Kwieciński K. , Słania J.
Published: September 2013

A dynamic development of steels for components for usc boilers used in fossil fired power plants creates new welding problems. Introduction of new combinations of alloying agents, which are used to improve mechanical properties, especially creep resistance, does not remain indifferent as to the weldability of the newest steels. Every new steel grade which will be used for pressure components in power plants boilers has to be precisely tested. The most important processes that require profound research are bending and welding. It is crucial to examine all new steel grades and use the knowledge to elaborate technologies which could be used during prefabrication and assembly of boiler installations. As an example 7CrMoVTiB10-10 also known as T/P24 is given.
Microstructure and Oxidation Resistance of an Aluminide Coating on the Nickel Based Superalloy Mar M247 Deposited by the CVD Aluminizing Process
Authors: Zielińska M. , Zagula-Yavorska M. , Sieniawski J. , Filip R.
Published: September 2013

An investigation was conducted to synthesize βNiAl coating on the nickel based superalloy Mar M247 in a chemical vapor deposition process (CVD). The low activity process of aluminizing was carried out for 8 hours at the temperature 1050°C. Surface morphology and cross-section microstructure of the diffusion coating were studied and compared by using an optical microscope, a scanning electron microscope (SEM) equipped with energy dispersive spectroscopy and an X-ray diffractometer. It was found that aluminide coating with the thickness of 37 μm consisted of two layers: an outer one and the inner interdiffusion one. The outer layer consists of single phase βNiAl. The inner one, consisted of βNiAl phase and carbides: MC and M23C6 types which were originally present in the substrate. Cyclic oxidation test was performed at 1000°C for 1000h in the air atmosphere. The aluminized samples exhibited a small mass increase and the α- Al2O3 oxide formed during oxidation test had a good adherence to the coating. The decrease of aluminum content in the coating with the prolongation of the oxidation time and the phase transformation of βNiAl to γ’ Ni3Al and to γNi solid solution were observed. The samples without the coating showed a strong mass decrease in comparison to the coated samples.
Kinetic Study of The Photoelectrochemical Gold Recovery from Diluted Chloride Solutions
Authors: Wojnicki M. , Tokarski T. , Kwolek P.
Published: September 2013

Au(III) was recovered from an acidic aqueous solution via a photoreduction technique under UV light irradiation. Titanium dioxide nanopowder was applied as a photocatalyst. Gold was deposited onto TiO2 surface in the form of nanoparticles with average dimensions between 20 and 30 nm. The influence of the Au(III), TiO2 and methanol initial concentrations on the reaction rate was determined. It was shown, that the rate of the gold photoreduction strongly depends on the concentration of TiO2 and methanol. The recovery of gold from the diluted acidic solutions containing as much as 1.97 and 0.197 mg/dm3 of Au(III) was also carried out. Obtained results suggest, that it is possible to recover about 45% of gold. Besides the losses during the filtration process due to the application of very fine TiO2 particles, oxygen dissolved in the solution as well as the hydrogen ions may take part in parasitic reactions and thus decrease the Au yield.
Complex Numerical Analysis of the Tube Forming Process Using Diescher Mill
Authors: Pater Z. , Kazanecki J.
Published: September 2013

This paper presents the results of FEM simulations of the rotary piercing process in which disc guiding devices of the Diescher type are used. During this process the material is formed by means of two skew rolls, two guiding devices, and the piercing plug mounted on the mandrel. The aim of the analysis was to determine the effect of the plug diameter, the plug advance, the feed angle and the diameter reduction on the piercing process. Nine cases of piercing with three different plugs used were analyzed. The effects of the basic process parameters on the tube shell diameter and the tool load were analyzed. The numerical results obtained using Simufact.Forming 10.0 were verified under experimental conditions in which the tube shell made from 100Cr6 bearing steel was pierced. The results of the FEM calculations show agreement with the experimental results.
Determination of Stress Values Based on Calculation of Photoelastic Constants on the Example of the Sub-Frame Connection with the Hull in a Small Training Aircraft
Authors: Czaja J. , Bernaczek J. , Śliwa R.
Published: September 2013

The above paper presents the example of sub-frame connections with the hull in a small training aircraft and the results of the analysis of a selected connection using the method of reflected light. The connection model was subjected to the loads similar to those existing in a structure using various materials of the connection. Thus, photoelastic deformation image, showing the load applied on the joint was obtained. Then, for the materials used in the model, photoelastic constants were determined, which were used to estimate the stress values in the model. The analysis allowed us to determine the effect of kind and features ( mainly hardness) of the used material pads, on mechanical behavior of the elements of joint.
Computer System for Identification of Material Models on the Basis of Plastometric Tests
Authors: Rauch L. , Sztangret L. , Pietrzyk M.
Published: September 2013

The paper describes the hybrid computer system dedicated to identification of models of materials subjected to thermomechanical processing. The functionalities of the system consist of plastometric tests data processing and application of the inverse analysis. The latter functionality is realized unconventionally, instead of the finite element method the metamodel is implemented using artificial neural network. The metamodels, used for simulations of the plastometric tests, are imported to the proposed computer system as external plugins, what guarantees flexibility and possibility of further development. On the other hand, application of rich optimization libraries assures the best possible solution of the problem. Basic principles of the inverse analysis with metamodels and mentioned optimization procedures are described in the paper. Selected examples of identification of models for various metallic materials recapitulate the paper.
Optimisation of the Deoxidation Degree and Modification on the Cast Steel Properties Improvement at Low Temperature
Authors: Sierant Z.
Published: September 2013

Industrial conditions of obtaining thick-walled and shaped castings intended for operations at temperatures: minus 40÷60°C are presented in the paper. The selection of a cast steel grade is based on known studies [1,10,14], however due to castings wall thickness (70-240mm), the way of preparing liquid metal (deep deoxidation and modification, argon stirring in a ladle) and conditions of filling mould cavities (gating system assuring quiet filling, directional solidification and avoiding a formation of inessential heat centres), were developed to assure the required impact strength. Maintaining these parameters as well as the selection of heat treatments for the produced massive castings allowed to achieve the impact strength over 50 J/cm2 at minus 40°. This value was obtained for walls of various thickness
Simulation of Solidification Conditions in High Quality Castings for Mining Industry
Authors: Głownia J. , Koshal D. , Skoczylas R. , Sobula S.
Published: September 2013

To obtain a right casting methoding of a yoke used in mining industry, a computer simulation of filling of mould cavity as well as casting solidification has been applied. Analysis of the casting solidification showed, that an initial casting methoding, based on common foundry practice, had to be changed. An initial bottom gating system was changed into a side-bottom one, what allowed smooth filling of mould cavity. Modified risering system enabled proper feeding of the casting. Ensuring high quality casting enable to substitute parts manufactured by forging
Wear Resistance of Graphitized Steels
Authors: Byelikov S. , Volchok I. , Akimov I.
Published: September 2013

Heat-treated graphitized steels with different carbon, silicon and copper contents have been the object of study. The influence of the composition on the structure and wear resistance (weight loss of the specimen) of graphitized steels (after hardening and tempering) under the conditions of metal to metal dry sliding friction with the use of Amsler-type friction machines, has been investigated in this work. Research results have shown that the main factors affecting wear resistance of graphitized steels have been not only their metal base hardness, but the quantity, shape and distribution of graphite inclusions uniformity in the structure of such steels as well. A regression dependence of the quantity of specimen’s weight loss on carbon, silicon and copper content has been obtained in the work. The highest wear resistance was pertained by the steel having the following content: 1.60. . . 1.70%C; 2.20. . . 2.30%Si; 0.80. . . 0.90%Cu; 0.60. . . 0.70%Mn; 0.15. . . 0.18%Cr; 0.22. . . 0.25%Al; up to 0.015%S and 0.024%P.
Quantitative and Qualitative Methods for Evaluation of Measurement Signals on the Example of Vibration Signals Analysis from the Corps of Prototype Reclaimer Regmas
Authors: Kowal J. , Dańko J. , Stojek J.
Published: September 2013

The article presents examples of vibration signals analysis derived from the research of prototype reclaimer REGMAS. After the division of the time-frequency analysis methods of measuring signals, their non-parametric and parametric models were estimated. At the end of the article the summary and conclusions were set.
Wear Resistance of 18%Cr-9%Ni Steel Used for Cast Parts of Pumps Operating in Corrosive – Erosive Environments
Authors: Kalandyk B.
Published: September 2013

This paper presents the results of experimental studies, the main aim of which has been to demonstrate that changes in the microstructure of austenitic 18%Cr-9%Ni cast steel provoked by the addition of 1.4% boron, and boron with titanium, give increased wear resistance. After melting the high-alloyed 18%Cr-9%Ni cast steel with an addition of boron, and boron with titanium, metallographic examinations were conducted using light microscopy and SEM. These examinations revealed in the austenitic structure of the 18%Cr-9%Ni cast steel, the presence of a eutectic rich in boron and chromium, and characterised by a microhardness of 1838-1890 μ HV20. Additionally, in the cast steel inoculated with boron and titanium, the presence of titanium nitride precipitates was observed. Changes that have occurred in the microstructure as a result of introducing the additions of boron, and boron with titanium, also caused an increase of the cast steel hardness from 212 HV30 to 290-320 HV30 and 320-350 HV30, respectively. To determine the abrasive wear resistance, 16-hour Miller test was performed (ASTM G 75-07), wherein the abrasive medium was a mixture of SiC and water. Obtaining the hard, rich in boron and chromium, eutectic and titanium nitride precipitates in the structure of 18%Cr-9%Ni cast steel increased the abrasive wear resistance by approximately 21%, according to the data recorded in the sixteenth hour of the test cycle. As an additional benchmark point for the results obtained served the wear resistant, structural, L35GSM steel used for castings working in difficult conditions. Comparing the values of abrasive wear resistance obtained for the 18%Cr-9%Ni cast steel and cast L35GSM steel, an increase in the wear resistance of the 18%Cr-9%Ni cast steel by about 35% has been proved.
Trends in the Development of High-Aluminium Zinc Alloys of Stable Structure and Properties
Authors: Krajewski W.K. , Greer A.L. , Krajewski P.K.
Published: September 2013

properties and structural stability. In a series of studies, Zn - (25-26) wt.% Al - (1-2.5) wt.% Cu alloys have been doped with different levels of added Ti. The alloys’ structure and mechanical properties have been studied using: SEM (scanning electron microscopy), LM (light microscopy), Dilatometry, Pin-on-Disc wear and Strength measurements. Grain refinement leads to significant improvement of ductility in the binary Zn-25Al alloy. In the ternary alloys Zn-26Al-Cu, replacing a part of Cu with Ti allows dimensional changes to be reduced while preserving good tribological properties.
Selection of Protective Coatings of Moulds for Castings of High-Manganese Cast Steel in Dependence of the Applied Moulding Sand Kind
Authors: Holtzer M. , Bobrowski A. , Drożyński D. , Mocek J.
Published: September 2013

High-manganese cast steels are characterised by a high abrasion resistance under friction conditions with a simultaneous influence of pressure and impacts. This cast steel is especially suitable for castings of excavator’s scoops, track links, streetcars crossovers, parts of crushers and mills for braking up of hard materials [1-4]. In order to obtain high quality castings of high-manganese cast steels in moulds on the high-silica sand matrices it is necessary to apply protective coatings, which prevent a direct contact between metal and matrix (SiO2). Manganese after being poured into a mould can undergo a partial oxidation forming MnO, which reacts with silica. As a result low-melting manganese silicates are formed, which in a form of a tight layer adhere to the casting surface, significantly increasing a labour input related to cleaning. Three kinds of protective coatings were tested: zirconium, corundum and magnesite. As a base moulding sands on high-silica sand matrices with three kinds of resol resins were applied. The quality of the obtained casting surface was assessed in dependence of the protective coating and resin kind and also in dependence of the metallostatic pressure value.
Optimization Methods for Lot-Sizing Problem in an Automated Foundry
Authors: Duda J. , Stawowy A.
Published: September 2013

In the paper we studied a production planning problem in a mid-size foundry that provides tailor-made cast products in small lots for a large number of clients. Assuming that a production bottleneck is the furnace, a mixed-integer programming (MIP) model is proposed to determine the lot size of the items and the required alloys to be produced during each period of the finite planning horizon that is subdivided into smaller periods. As using an advanced commercial MIP solvers may be impractical for more complex and large problem instances, we proposed and compared a few computational intelligence heuristics i.e. tabu search, genetic algorithm and differential evolution. The examination showed that heuristic approaches can provide a good compromise between speed and quality of solutions and can be used in real-world production planning.
The Methodology of Virtual Foundry Developing
Authors: Brzeziński M. , Stawowy A. , Wrona R.
Published: September 2013

Systemic approach to design of factories requires that engineering, organisational and economic aspects should be considered concurrently. That prompts the need to develop a solution, based on the state-of-the-art IT technologies, to enable us to solve the problems associated with foundry production planning. The paper outlines a methodology of creating the simulation model of a virtual foundry, as a tool for foundry design. An integrative approach is suggested for development of a complete foundry model, enabling the design of more efficient production systems. The underlying principles of such models are discussed, the basic stages involved in the methodology are outlined and the range of its applicability is defined.
Algorithm for Burden Calculation for Foundry Furnaces Using Charge Materials with an Uncertain Composition
Authors: Ziółkowski E.
Published: September 2013

Calculation of charge burden to foundry furnaces by computing the proportions of particular charge materials is a most complicated task as a variety of technological aspects have to be considered. For practical and economic reasons, this problem is typically solved using computer-based optimisation methods, the main criterion being the optimal amount of charge materials related to the lowest costs of the burden. The problem is further complicated when the chemical composition of the charge materials is not accurately defined. So far the calculations of the charge burden were performed in order to work out the detailed melt procedure, which was to be modified and corrected by the trial and error method in subsequent melt processes.

An algorithm has been developed for use in calculating the charge burden depending on the target chemical composition of the casting alloy. Of particular importance is the application of the algorithm when the process conditions are changeable.
Influence of the Gas Dosage Method on Pressure Changes and Technological Properties of Core Sand Used in the Technology Resol-Co2
Authors: Jamrozowicz Ł.
Published: September 2013

The results of gas pressure measurements in intergranular spaces of fast-setting sands hardened by active gaseous factor are presented in the paper. The research stand and the measuring methodology are described. Investigations concern the determination and recording gas pressure changes in the core sand along the hardened core, in three measuring points. The hardening gas was introduced both in a continuous and impulse way (gas-pause) at a constant pressure. The determined pressure changes of the active gas, which takes part in the chemical reaction of the hardening process, are compared with pressure changes of the neutral gas. The influence of the impulse way of a gas dosage on the core sand strength properties is presented as well as methods of limiting the active gas consumption are shown.
Examinations of Parameters Influencing the Outflow of Two Phase Air-Sand Stream from Machine Chamber and Core Box Filling in Shooting Process
Authors: Fedoryszyn A. , Dańko R.
Published: September 2013

The study investigates the key aspects involved in the flow of the air-sand stream from the machine chamber and in the core box filling in the core shooting and core blowing processes.

The prevailing tendency to manufacture thin-walled castings with intricate channel structures has become the major determinant of castings quality and production rates. An important parameter of most core sand used in the shooting processes is the ability to eject from the machine chamber and the core-box filling capability. These properties are the key factors determining the feasibility of manufacturing intricate cores and the process efficiency. The research work outlined in this study focuses on establishing the performance criteria of core sand ejection from the machine chamber and of core box filling and sand compaction.

The results given below were obtained for several new-generation core sand types, containing organic and inorganic binders, and designed to be used in hot-box, warm box and warm air processes.
Performance Evaluation of Rotary Mixers Through Monitoring of Power Energy Parameters
Authors: Smyksy K. , Ziółkowski E. , Wrona R. , Brzeziński M.
Published: September 2013

A method is outlined that can be adopted for measuring the power demand by moulding sand mixers using a dedicated computer system enabling the monitoring and recording of instantaneous voltage and current levels of power taken up by foundry machines and installations. This system allows the operational parameters of electric-powered devices to be effectively monitored. Of particular importance is the energy efficiency level. Monitoring of the machine operation is also required for evaluation of the sand preparation processes. The methodology of measurements and processing of measurement data is explained using the example of a state-of-the-art rotary mixer for laboratory applications. Tests have confirmed the adequacy and good performance of the microprocessor system used in measurements, allowing the energy efficiency parameters of the mixer drive to be determined. The fundamental aspects involved in power demand monitoring include: optimisation and control of the mixing process, taking into account the sand quality and mixer performance. It has to be emphasised that the measurement results can be also utilised in optimisation of the machine’s constructional and operational features. Tests confirm that variations of moisture content in sand can impact on selected power energy parameters.
Usefulness of Foundry Tooling Materials in Microwave Heating Process
Authors: Granat K. , Opyd B. , Nowak D. , Stachowicz M. , Jaworski G.
Published: September 2013

The paper describes preliminary examinations on establishing usefulness criteria of foundry tooling materials in the microwave heating technology. Presented are measurement results of permittivity and loss tangent that determine behaviour of the materials in electromagnetic field. The measurements were carried-out in a waveguide resonant cavity that permits precise determination the above-mentioned parameters by perturbation technique. Examined were five different materials designed for use in foundry tooling. Determined was the loss factor that permits evaluating usefulness of materials in microwave heating technology. It was demonstrated that the selected plastics meet the basic criterion that is transparency for electromagnetic radiation.
Tribological and Corrosive Properties of the Parts of Machines with Surface Alloy Layer
Authors: Szajnar J. , Walasek A. , Baron C.
Published: September 2013

There are presented the results of researches conducted on the steel cast with surface alloy layer in this work. The measurement of the thickness, hardness and abrasion wear resistance was conducted in accordance with norm ASTM G 65-00. The measurement of the corrosion resistance was conducted in accordance with the potentio - dynamical method. It is shown that it is possible to obtain the alloy surface layer of different thickness by control of some factors: pouring temperature Tzal , diameter of grain of FeCrC alloy Zw and the thickness of the cast wall gśo. It is proved that the smaller diameter of ferrochromium grain, the thicker surface alloy layer. It is also said that the higher pouring temperature and thicker the cast wall, the thicker surface alloy layer. What is more - the smaller thickness of the cast wall, the bigger hardness and abrasion wear resistance.
The Lean Manufacturing Tools in Polish Foundries
Authors: Jezierski J. , Janerka K.
Published: September 2013

The concept of Lean Manufacturing (or Lean Production) is widely present in the quality management systems of the best factories. Foundry plants in Poland have continuously been implementing modern management tools; however, the experiences of the authors show that the usage of lean tools is at a lower level in domestic foundries than in similar plants abroad. This was the reason why a survey was prepared and over 300 foundry plants were questioned regarding the application of Lean Manufacturing tools. The questions (20 in total) asked if and what tools are implemented in the plant and what benefits have been achieved, or why lean tools have not been implemented in a particular plant. The answers were thoroughly analysed and the results show that, among others, only 29% of all foundries use lean tools, and the main reason why most of them do not is that these tools are not understood well enough.
Modification of Pure Al and AlSi2 Alloy Primary Structure with Use of Electromagnetic Stirring Method
Authors: Wróbel T. , Szajnar J.
Published: September 2013

The paper presents modification of primary structure of Al 99,5% and 99,8% purity and AlSi2 alloy by electromagnetic stirring of liquid metal within foundry mould. The movement of solidifying liquid metal within the mould was forced by horizontal electromagnetic field produced by the induction coil (stirrer), supplied by current of elevated frequency. The structure refinement obtained by electromagnetic stirring was compared with refinement obtained by traditional modification, i.e. by introducing Ti, B, C and Sr modifying additives into melt. The results of studies show possibility of effective primary structure refinement of pure Al and selected Al-Si alloy by using only horizontal electromagnetic field, without necessity of Ti, B and C additives application.
A New Method for the Measurement of Flowability of Green Moulding Sand
Authors: Bast J.
Published: September 2013

The production of castings by green sand moulds is a very important method for the manufacture of final products for different sectors of industry. In this green sand moulding process the quality of castings depends strongly on the quality of the mould, which in turn is determined by parameters such as the type of foundry machine, the characteristics of the moulding sand and the specifications of the patterns. The mould’s stability for use casting is achieved by filling and compacting moulding sand. This means, that the clay-bonded moulding sand is changed from the free flowing to the compacted state. In this process flowability is a very important parameter. Therefore, a variety of methods for the determination of flowability have been in use. However, it is fair to say that these methods do no longer meet the requirements of the modern moulding process. This paper introduces a new method for the determination of flowability of clay-bonded moulding sand using a specifically designed type of density sensor that was developed by a research team led by Professor Jürgen L. Bast at the Mechanical Department of Technical University Bergakademie Freiberg. The high levels of accuracy in the determination of flowability that this method is capable of achieving have been tested and indeed proven by varying sand parameters such as water and clay content, grain composition, mixing time, and compaction pressure. A further innovative characteristics of this new method of sensor-based flowability measurement is the possibility of using the sensor not only for the lab-based testing of sands but in the actual mould during the production process in the foundry, which allows to determine whether the sand in the mould has the required qualities based on real-time flowability measurements.