bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microstructure and Thermomechanical Properties of Magnesium Alloys Castings
Authors: Lichý P. , Cagala M. 
Published: September 2012

Microstructure and Thermomechanical Properties of Magnesium Alloys Castings
Magnesium alloys thanks to their high specific strength have an extensive potential of the use in a number of industrial applications. The most important of them is the automobile industry in particular. Here it is possible to use this group of materials for great numbers of parts from elements in the car interior (steering wheels, seats, etc.), through exterior parts (wheels particularly of sporting models), up to driving (engine blocks) and gearbox mechanisms themselves. But the use of these alloys in the engine structure has its limitations as these parts are highly thermally stressed. But the commonly used magnesium alloys show rather fast decrease of strength properties with growing temperature of stressing them. This work is aimed at studying this properties both of alloys commonly used (of the Mg-Al-Zn, Mn type), and of that ones used in industrial manufacture in a limited extent (Mg-Al-Sr). These thermomechanical properties are further on complemented with the microstructure analysis with the aim of checking the metallurgical interventions (an effect of inoculation). From the studied materials the test castings were made from which the test bars for the tensile test were subsequently prepared. This test took place within the temperature range of 20°C - 300°C. Achieved results are summarized in the concluding part of the contribution.
The Comparison of Selected Methods of Cast Iron Spheroidization in Industrial Conditions
Authors: Válek T. , Šimon P. , Střílková L. 
Published: September 2012

The Comparison of Selected Methods of Cast Iron Spheroidization in Industrial Conditions
Production of spheroidal graphite cast iron is today quite mastered technology. There are many methods achieving the nodular graphite morphology. Each of these methods have specific characteristics and requirements to technical support, properties and the type of applied modifier. Selection of the spheroidization method is dependent on foundry disposition, production character, economic balance, quality requirements, etc. In case of centrifugally casting the core, which fills body and neck of the roll, is created by ductile iron. Considering the sophisticated production of centrifugally cast rolls for hot rolling mills it is necessary to ensure a high reproducibility and reliability of ductile cast iron production quality in the bulk range of 9-18 t per tapping. These conditions are in the Roll Foundry in Vítkovicke Slevarny, spol. s r.o. provided and verified mastered overpour method and the newly injection of cored wire in the melt.
Heat Treatment of AlZn10Si7MgCu Alloy and its Effect on Change of Mechanical Properties
Authors: Pezda J. 
Published: September 2012

Heat Treatment of AlZn10Si7MgCu Alloy and its Effect on Change of Mechanical Properties
The most important parameters which predetermine mechanical properties of a material in aspects of suitability for castings to machinery components are: tensile strength (Rm), elongation (A5, hardness (HB) and impact strength (KCV). Heat treatment of aluminum alloys is performed to increase mechanical properties of the alloys mainly. The paper comprises a testing work concerning effect of heat treatment process consisting of solution heat treatment and natural ageing on mechanical properties and structure of AlZn10Si7MgCu alloy moulded in metal moulds. Investigated alloy was melted in an electric resistance furnace. Run of crystallization was presented with use of thermal-derivative method (ATD). This method was also implemented to determination of heat treatment temperature ranges of the alloy. Performed investigations have enabled determination of heat treatment parameters' range, which conditions suitable mechanical properties of the investigated alloy. Further investigations will be connected with determination of optimal parameters of T6 heat treatment of the investigated alloy and their effect on change of structure and mechanical/technological properties of the investigated alloy.
Structure of X5CrNi18-10 and S355NL Steels after Remelting with the Electric Arc
Authors: Adamiak S. 
Published: September 2012

Structure of X5CrNi18-10 and S355NL Steels after Remelting with the Electric Arc
The work presents the results of the research and tests of the surface machining of the S355NL and X5CrNi18-10 steels with the concentraded stream of heat with the usage of the GTAW method. The surface layers of the tested steels were remelted with the electric arc using the current of the electric arc 50, 100, 150 and 200A. The machining was done in the atmosphere of argon with the constant speed of the welding head. A microscope examination was performed of the obtained structure and measurements of depth, width and hardness of the received surface layer were performed. Moreover the relation between the current of the electric arc and geometry of the remelted layers with their microhardness was examined.
The Influence of Ingate Size on the Lost Foam Casting Process
Authors: Pacyniak T. , Kaczorowski R. 
Published: September 2012

The Influence of Ingate Size on the Lost Foam Casting Process
The article presents analysis of the influence of ingate size on the Lost Foam casting process. In particular, analysis of simulation tests has been carried out to determine the ingate size influence on the rate of filling of the mould cavity, pressure in the gas gap and size of the gas gap. A specially prepared mathematical model of the process and an original calculation algorithm were used in simulation tests of full-mould casting. The tests have indicated that the increase of the ingate size results in the increase of filling rate and increase of pressure of gases in the gas gap. However, significant influence on mould cavity filling occurs only when the ingate size is less than ~1 cm2.
The Influence of the Shape of the Reaction Chamber on Spheroidisation of Cast Iron Produced in the Lost Foam Casting Process with Use of the Inmold Method
Authors: Just P. , Pacyniak T. 
Published: September 2012

The Influence of the Shape of the Reaction Chamber on Spheroidisation of Cast Iron Produced in the Lost Foam Casting Process with Use of the Inmold Method
The article presents the results of the research on the influence of the shape of reaction chamber on spheroidisation of cast iron produced with use of the inmold method. The amounts of nodular graphite precipitates in castings produced with the use of different reaction chambers have been compared.
The Structure of the Silumin Coat on Alloy Cast Steels
Authors: Szymczak T. 
Published: September 2012

The Structure of the Silumin Coat on Alloy Cast Steels
The work presents the analysis results of the structure of the coat obtained by dipping in silumin AlSi5 of two grades of alloy cast steel: GX6CrNiTi18-10 (LH18N9T) and GX39Cr13 (LH14). The temperature of the silumin bath was 750±5°C, and the hold-up time of the cast steel element τ = 180 s. The absolute thickness of the coat obtained in the given conditions was g = 104 μm on cast steel GX6CrNiTi18-10 and g = 132 μm on GX39Cr13. The obtained coat consisted of three layers of different phase structure. The first layer from the base "g1" was constructed of the phase AlFe including Si and alloy additives of the tested cast steel grades: Cr and Ni (GX6CrNiTi18-10) and Cr (GX39Cr13). The second layer "g1" of intermetallic phases AlFe which also contains Si and Cr crystallizes on it. The last, external layer "g2" of the coat consists of the silumin containing the intermetallic phases AlFeSi which additionally can contain alloy additives of the cast steel. It was shown that there were no carbides on the coat of the tested cast steels which are the component of their microstructure, as it took place in the case of the coat on the high speed steels.
Abrasive Wear Resistance of Cast Iron with Precipitates of Spheroidal VC Carbides
Authors: Kawalec M. , Olejnik E. 
Published: September 2012

Abrasive Wear Resistance of Cast Iron with Precipitates of Spheroidal VC Carbides
The paper presents the results of abrasive wear resistance tests carried out on high-vanadium cast iron with spheroidal VC carbides. The cast iron of eutectic composition was subjected to spheroidising treatment using magnesium master alloy. The tribological properties were examined for the base cast iron (W), for the cast iron subjected to spheroidising treatment (S) and for the abrasion-resistant steel (SH). Studies have shown that high-vanadium cast iron with both eutectic carbides and spheroidal carbides has the abrasion resistance twice as high as the abrasion-resistant cast steel. The spheroidisation of VC carbides did not change the abrasion resistance compared to the base high-vanadium grade.
The Analysis of the Influence of the Polystyrene Patterns Shaping Parameters on the Resistance Properties
Authors: Pacyniak T. , Buczkowska K. , Bogus W. 
Published: September 2012

The Analysis of the Influence of the Polystyrene Patterns Shaping Parameters on the Resistance Properties
This work presents the technology of making foam plastics patterns used in casting as well as the final shaping stand. The analysis of the sintering process was carried out aiming at determining the influence of the pressure and the time of sintering on the flexural strength properties. The analysis of the research results confirmed that when the sintering pressure grows to the value of Pa =1,7 bar the flexural strength also increases, when the pressure value is higher than that, the degradation of the material takes place and the strength properties decrease.
Applications of Monitoring of Electric Power Parameters to Performance Evaluation of a Model Vacuum-Assisted Moulding Installation
Authors: Ziółkowski E. , Brzeziński M. , Wrona R. , Smyksy K. , Zyzak P. 
Published: September 2012

Applications of Monitoring of Electric Power Parameters to Performance Evaluation of a Model Vacuum-Assisted Moulding Installation
Vacuum conditions in foundry installations are generated using electric-driven vacuum pumps. The purpose of the experiment is to evaluate the performance of a vacuum-assisted system for compaction of moulding sand basing on registered plots of selected electric power parameters of the power-supplying system of the pumps. Model testing done on an experimental vacuum system installation, power-supplied from a system incorporating the recorders of instantaneous current and voltage values. Following the numerical procedure, the experimental data are analysed to yield mathematical relationships between the variations of the generated vacuum pressure levels and variations of selected electric power parameters. Registered and computed values of selected parameters: instantaneous and RMS voltage and current values, active, reactive and apparent power levels and power coefficient allow for diagnosing the adequacy and reliability of the system operation. According to the authors, the applied monitoring of the power parameters of a vacuum-assisted installation may become an effective and easy practical method of evaluating the performance of such installations, used also in foundry plants.
Global Muscle Strength But Not Grip Strength Predicts Mortality and Length of Stay in a General Population in a Surgical Intensive Care Unit
Authors: Lee Jeanette J. , Waak Karen , Grosse-Sundrup Martina , Xue Feifei , Lee Jarone , Chipman Daniel , Ryan Cheryl , Bittner Edward A. , Schmidt Ulrich , Eikermann Matthias 
Published: September 2012

BackgroundParesis acquired in the intensive care unit (ICU) is common in patients who are critically ill and independently predicts mortality and morbidity. Manual muscle testing (MMT) and handgrip dynamometry assessments have been used to evaluate muscle weakness in patients in a medical ICU, but similar data for patients in a surgical ICU (SICU) are limited.ObjectiveThe purpose of this study was to evaluate the predictive value of strength measured by MMT and handgrip dynamometry at ICU admission for in-hospital mortality, SICU length of stay (LOS), hospital LOS, and duration of mechanical ventilation.DesignThis investigation was a prospective, observational study.MethodsOne hundred ten patients were screened for eligibility for testing in the SICU of a large, academic medical center. The Acute Physiology and Chronic Health Evaluation (APACHE) II score, diagnoses, and laboratory data were collected. Measurements were obtained by MMT quantified with the sum (total) score on the Medical Research Council Scale and by handgrip dynamometry. Outcome data, including in-hospital mortality, SICU LOS, hospital LOS, and duration of mechanical ventilation, were collected for all participants.ResultsOne hundred seven participants were eligible for testing; 89% were tested successfully at a median of 3 days (25th–75th percentiles=3–6 days) after admission. Sedation was the most frequent barrier to testing (70.6%). Manual muscle testing was identified as an independent predictor of mortality, SICU LOS, hospital LOS, and duration of mechanical ventilation. Grip strength was not independently associated with these outcomes.LimitationsThis study did not address whether muscle weakness translates to functional outcome impairment.ConclusionsIn contrast to handgrip strength, MMT reliably predicted in-hospital mortality, duration of mechanical ventilation, SICU LOS, and hospital LOS.
Seasonal influence on the thyroid gland in healthy dogs of various breeds in different weights
Authors: Fialkovičová Mária , Mardzinová Silvia , Benková Marta , Mojžišová Jana , Gaálová Monika , Sesztáková Edina 
Published: September 2012

The aim of our study was to evaluate the influence of seasonal ambient temperature on the thyroid gland function in terms of serum total thyroxine (TT4), free thyroxine (fT4), total triiodothyronine (TT3), and canine thyroid stimulating hormone (cTSH) concentrations in healthy dogs of various breeds living outdoors and to compare them with those living indoors in flats and houses. The monitoring was conducted for 5 years and our study included 162 indoor dogs and 148 outdoor dogs of both sexes from 2 to 12 years of age, categorised into 3 groups according to their body weight: large (n = 17), medium (n = 16) and small (n = 17) breeds. Comparison of the seasonal serum TT4 and fT4 concentrations in both the indoor and outdoor dogs confirmed their fluctuation in relation to the ambient temperature in all weight groups with the lowest average of TT4 and fT4 concentrations recorded in summer and the highest ones in winter. In dogs kept outdoors, the fluctuation of hormone values was significant (P< 0.05). Seasonal serum cTSH fluctuation was found to be significant (P< 0.05) only in the medium breeds living outdoors, but their concentrations did not exceed the reference ranges. The 5-year monitoring of serum TT3 in indoor and outdoor dogs of large, medium, and small breeds clearly showed that its concentrations were not influenced by varying ambient temperature. The study provides for the first time evidence that serum TT4 and fT4 concentrations in dogs kept outdoors directly depend on ambient temperature. This correlation was also expressed by mathematical equations.
Gamma Knife surgery in the treatment paradigm for foramen magnum meningiomas
Authors: Zenonos Georgios , Kondziolka Douglas , Flickinger John C. , Gardner Paul , Lunsford L. Dade 
Published: September 2012

Object
Microsurgical management of foramen magnum meningiomas (FMMs) can be associated with significant morbidity and mortality. Stereotactic radiosurgery may be an efficient and safe alternative treatment modality for such tumors. The object of this study was to increase the documented experience with Gamma Knife surgery (GKS) for FMMs and to delineate its role in an overall management paradigm.

Methods
The authors report on their experience with 24 patients harboring FMMs managed with GKS. Twelve patients had primary symptomatic tumors, 5 had asymptomatic but enlarging primary tumors, and 7 had recurrent or residual tumors after a prior surgery.

Results
Follow-up clinical and imaging data were available in 21 patients at a median follow-up of 47 months (range 3–128 months). Ten patients had measurable tumor regression, which was defined as an overall volume reduction > 25%. Eleven patients had no further tumor growth. Two patients died as a result of advanced comorbidities before follow-up imaging. One patient was living 8 years after GKS but had no clinical evaluation. Ten of 17 symptomatic patients with at least 6 months of follow-up had symptom improvement, and 7 remained clinically stable. Smaller tumors were more likely to regress. No patient suffered an adverse radiation effect after radiosurgery.

Conclusions
Gamma Knife surgery was a safe management strategy for small, minimally symptomatic, or growing FMMs as well as for residual tumors following conservative microsurgical removal.
Brain tissue oxygen monitoring after severe traumatic brain injury in children: relationship to outcome and association with other clinical parameters
Authors: Stippler Martina , Ortiz Veronica , Adelson P. David , Chang Yue-Fang , Tyler-Kabara Elizabeth C. , Wisniewski Stephen R. , Fink Ericka L. , Kochanek Patrick M. , Brown S. Danielle , Bell Michael J. 
Published: September 2012

Object
Minimizing secondary brain injuries after traumatic brain injury (TBI) in children is critical to maximizing neurological outcome. Brain tissue oxygenation monitoring (as measured by interstitial partial pressure of O2 [PbO2]) is a new tool that may aid in guiding therapies, yet experience in children is limited. This study aims to describe the authors' experience of PbO2 monitoring after TBI. It was hypothesized that PbO2 thresholds could be established that were associated with favorable neurological outcome, and it was determined whether any relationships between PbO2 and other important clinical variables existed.

Methods
Forty-six children with severe TBI (Glasgow Coma Scale score ≤ 8 after resuscitation) who underwent PbO2 and brain temperature monitoring between September 2004 and June 2008 were studied. All patients received standard neurocritical care, and 24 were concurrently enrolled in a trial of therapeutic early hypothermia (n = 12/group). The PbO2 was measured in the uninjured frontal cortex. Hourly recordings and calculated daily means of various variables including PbO2, intracranial pressure (ICP), cerebral perfusion pressure (CPP), mean arterial blood pressure, partial pressure of arterial O2, and fraction of inspired O2 were compared using several statistical approaches. Glasgow Outcome Scale scores were determined at 6 months after injury.

Results
The mean patient age was 9.4 years (range 0.1–16.5 years; 13 girls) and 8554 hours of monitoring were analyzed (PbO2 range 0.0–97.2 mm Hg). A PbO2 of 30 mm Hg was associated with the highest sensitivity/specificity for favorable neurological outcome at 6 months after TBI, yet CPP was the only factor that was independently associated with favorable outcome. Surprisingly, instances of preserved PbO2 with altered ICP and CPP were observed in some children with unfavorable outcomes.

Conclusions
Monitoring of PbO2 demonstrated complex interactions with clinical variables reflecting intracranial dynamics using this protocol. A higher threshold than reported in studies in adults was suggested as a potential therapeutic target, but this threshold was not associated with improved outcomes. Additional studies to assess the utility of PbO2 monitoring after TBI in children are needed.
Computed tomography morphometric analysis for lateral mass screw placement in the pediatric subaxial cervical spine
Authors: Al-Shamy George , Cherian Jacob , Mata Javier A. , Patel Akash J. , Hwang Steven W. , Jea Andrew 
Published: September 2012

Object
Lateral mass screws are routinely placed throughout the subaxial cervical spine in adults, but there are few clinical or radiographic studies regarding lateral mass fixation in children. The morphology of pediatric cervical lateral masses may be associated with greater difficulty in obtaining adequate purchase. The authors examined the lateral masses of the subaxial cervical spine in pediatric patients to define morphometric differences compared with adults, establish guidelines for lateral mass instrumentation in children, and define potential limitations of this technique in the pediatric age group.

Methods
Morphometric analysis was performed on CT of the lateral masses of C3–7 in 56 boys and 14 girls. Measurements were obtained in the axial, coronal, and sagittal planes.

Results
For most levels and measurements, results in boys and girls did not differ significantly; the few values that were significantly different are not likely to be clinically significant. On the other hand, younger (< 8 years of age) and older children (≥ 8 years of age) differed significantly at every level and measurement except for facet angularity. Sagittal diagonal, a measurement that closely estimates screw length, was found to increase at each successive caudal level from C-3 to C-7, similar to the adult population. A screw acceptance analysis found that all patients ≥ 4 years of age could accept at least a 3.5 × 10 mm lateral mass screw.

Conclusions
Lateral mass screw fixation is feasible in the pediatric cervical spine, particularly in children age 4 years old or older. Lateral mass screw fixation is feasible even at the C-7 level, where pedicle screw placement has been advised in lieu of lateral mass screws because of the small size and steep trajectory of the C-7 lateral mass. Nonetheless, all pediatric patients should undergo high-resolution, thin-slice CT preoperatively to assess suitability for lateral mass screw fixation.
Stickstoffeinträge in den Schweizer Wald: Ausmass und Auswirkungen
Authors: Braun Sabine , Rihm Beat , Flückiger Walter 
Published: September 2012

Inputs of nitrogen to Swiss forests: extent and effects
Because of their rough surface forests are an efficient sink for nitrogen compounds emitted by industry, traffic and agriculture. Deposition maps reveal that nitrogen deposition in Swiss forests exceed 30 kg N/(ha × yr) in various regions, which is clearly higher than the critical loads set by the United Nations Economic Commission for Europe (UNECE). The calculated deposition data base on emission inventories, dispersion models, measurements of various deposition components (gaseous, aerosols, wet) as well as on balance calculations. The evaluation of the effects on forests bases on two summary reports: the workshop report of a UNECE meeting on critical loads for nitrogen held in 2010 and a summary of own nitrogen addition experiments published in 2011. The presented data suggest that in Switzerland nitrogen inputs are high enough to cause changes of forest ecosystems.
Ozonbelastung von Waldbäumen in der Schweiz und damit verbundene Wachstumseinbussen
Authors: Braun Sabine , Rihm Beat 
Published: September 2012

Ozone impact on forest trees in Switzerland and resulting growth reductions
Ozone (O3) is highly phytotoxic. Basing on dose-effect relationships resulting from fumigation experiments, the United Nations Economic Commission for Europe (UNECE) has set critical levels for protection of the vegetation. The present article compares the AOT40 (accumulated ozone over a threshold of 40 ppb) summing up hourly ozone concentrations with a flux-based risk assessment taking into account stomatal ozone uptake. Both ozone quantifications were calculated for rural monitoring stations in Switzerland, mapped and compared to the corresponding critical levels. The data suggest that the ozone load in Switzerland is high enough to provoke clear reductions in forest growth.