This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens...
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This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens were heat treated to obtain hardness of 294, 445 and 595 HV200 (29, 45 and 55 HRC). Erosion tests were carried out at impingement angles from 20° to 90° and air drag pressures of 1.38, 2.07 and 2.76 bar (20, 30 and 40 psi). The main results are summarized as follows:(i) The harder material, the lower erosion;(ii) the maximum erosion rate is at 30°;(iii) Little difference in erosion rate at impact angle of 60° and 90° for a constant pressure tested regardless of the hardness level;(iv) As the pressure increases, so does the erosion rate, being more sensitive for low impact angles. Finally, a differential form of the general erosion equation is applied on a practical core-making case to evaluate the erosion rate of the H13 steel at 30° and 90° impingement angles.
ErNi2 ribbons were produced by rapid solidification using the melt spinning *** structural,magnetic and magnetocaloric properties in the as-solidified state were studied by X-ray diffraction,scanning electron microsco...
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ErNi2 ribbons were produced by rapid solidification using the melt spinning *** structural,magnetic and magnetocaloric properties in the as-solidified state were studied by X-ray diffraction,scanning electron microscopy,magnetization and specific heat *** are single phase with the MgCu2-type crystal structure,a Curie temperature TC of 6.8 K and a saturation magnetization at2 K and 5 T of 124.0 A·m2/*** a magnetic field change μ0△H of 5 T(2 T) ribbons show a maximum magnetic entropy change |△SMpeak| of 24.1(16.9) J/(kg·K),and an adiabatic temperature change △Tadmax of8.1(4.4) K;this is similar to the previously reported literature for bulk alloys that were processed through conventional melting techniques followed by prolonged thermal *** addition,the samples also show slightly wider △SM(T) curves with respect to bulk alloys leading to a larger refrigerant capacity.
Background Obesity is a multifactorial chronic disease with a high,increasing worldwide *** causes account for 7%of the cases in children with extreme *** sources This narrative review was conducted by searching for p...
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Background Obesity is a multifactorial chronic disease with a high,increasing worldwide *** causes account for 7%of the cases in children with extreme *** sources This narrative review was conducted by searching for papers published in the PubMed/MEDLINE,Embase and SciELO databases and included 161 *** search used the following search terms:"obesity","obesity and genetics","leptin","Prader-Willi syndrome",and"melanocortins".The types of studies included were systematic reviews,clinical trials,prospective cohort studies,cross-sectional and prospective studies,narrative reviews,and case *** The leptin-melanocortin pathway is primarily responsible for the regulation of appetite and body ***,several important aspects of the pathophysiology of obesity remain *** causes of obesity can be grouped into syndromic,monogenic,and polygenic causes and should be assessed in children with extreme obesity before the age of 5 years,hyperphagia,or a family history of extreme obesity.A microarray study,an analysis of the melanocortin type 4 receptor gene mutations and leptin levels should be performed for this *** are three therapeutic levels:lifestyle modifications,pharmacological treatment,and bariatric *** Genetic study technologies are in constant development;however,we are still far from having a personalized approach to genetic causes of obesity.A significant proportion of the affected individuals are associated with genetic causes;however,there are still barriers to its approach,as it continues to be underdiagnosed.
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