Effects of Trace Elements on the Microstructural and Machinability Characteristics of Al–Si–Cu–Mg Castings

This study was undertaken to emphasize the influence of Sn and Bi addition on the machinability of Sr-modified, grain-refined, and heat-treated Al–Si B319 and 396 alloys. Drilling and tapping tests were conducted to examine the cutting forces, tool life, tool wear, built-up edge evolution, and chip shape. Microstructures were examined using optical and electron microscopy. Drilling test results show that the B319.2 alloy with 0.15%Sn yields the longest drill life, i.e., twice that of the B319.2 alloy containing 0.5%Bi, and one-and-a-half times that of the B319.2 alloy containing 0.15%Sn + 0.5%Bi. The presence of 0.5%Bi in the B319.2 alloy causes a deterioration of drill life (cf., 1101 holes with 2100 holes drilled in the B319.2 alloy containing 0.15%Sn). The α-Fe phase in the 396 alloy produces the highest number of holes drilled compared with alloys containing sludge or β-Fe. The presence of sludge decreases the drill life by 50%. Built-up edge (BUE) measurements and optical photographs show little change in the BUE width for different numbers of holes except for the B319.2 alloy containing 0.5%Bi, which shows a slightly lower width (0.166 mm) compared with that containing 0.15% Sn (0.184 mm) or 0.15%Sn + 0.5%Bi (0.170 mm).

Evalueren van kwaliteit van leven bij thuiswonende ouderen

De groeiende groep thuiswonende ouderen in Nederland vraagt om een goede ondersteuning door inzet van de juiste diensten, zoals huishoudelijke hulp of dagbesteding. Het bepalen van belangrijke uitkomsten is daarin cruciaal en hiervoor zijn brede uitkomsten in termen van kwaliteit van leven (KvL) relevant, waarbij gekeken wordt naar de invloed van diensten op iemands mogelijkheden of capabilities. In dit artikel worden de ontwikkeling en inhoud van de Adult Social Care Outcomes Toolkit (Nederlandstalige versie, ASCOT-NL) en de Extended Quality of Life Tool (EQLT) beschreven en de toepassingsmogelijkheden in de evaluatie van zorg belicht. Beide instrumenten beogen effecten van zorg op KvL van thuiswonende ouderen te meten op meerdere relevante domeinen. De ASCOT-NL kent acht domeinen; de EQLT bevat deze acht domeinen en voegt daar zes domeinen aan toe, hetgeen resulteert in totaal veertien domeinen. De domeinen van de ASCOT-NL zijn gebaseerd op de doelen van sociale ondersteuning en zorg; de aanvullende domeinen van de EQLT zijn gebaseerd op empirisch onderzoek naar KvL vanuit het perspectief van thuiswonende ouderen en de manier waarop zorg kan bijdragen aan KvL.

Influence of Microgroove Structure on Cutting Performance and Chip Morphology during the Turning of Superalloy Inconel 718

This study designed a new microgroove cutting tool to machine Inconel 718 and focused on the effect of microgroove structure on the cutting performance and chip morphology during the turning. A comparative analysis of the cutting force, cutting temperature, tool life, tool wear, and chip morphology of the microgroove cutting tool and the original cutting tool was conducted. The main cutting force and temperature of the microgroove cutting tool were reduced by 12% and 12.17%, respectively, compared with the original cutting tool. The microgroove cutting tool exhibited a significant improvement compared with the original cutting tool, which extended the tool life by up to 23.08%. Further, the microgroove cutting tool distorted the curl radius of the chips extensively. The experimental results showed that the microgroove structure can not only improve the tool life, but also improve the chip breaking effect.

Validation of the Hungarian version of the SRI Questionnaire

Background Home mechanical ventilation is a reliable treatment for patients suffering from chronic respiratory failure, improving survival and quality of life. Prevalence has been increasing worldwide as a result of evolving technical possibilities, telemedicine and improving national guidelines. Projects to establish a national guideline and registry for patients treated with home mechanical ventilation are currently under way in Hungary and our aim was to validate a quality of life questionnaire suited for evaluation and follow up in this specific patient group. The Severe Respiratory Insufficiency Questionnaire (SRI) is a quality of life tool designed to evaluate patients receiving home mechanical ventilation and has been validated both in patient groups receiving invasive and noninvasive ventilation. Methods The Hungarian version of the SRI was created using the translation-backtranslation method, which was then tested for validity, viability and reliability in a cohort involving patients from three centers, receiving long-term home mechanical ventilation for chronic respiratory failure through an invasive or noninvasive interface. Patient data was collected (demographic data, lung function test, arterial blood gas, ventilation settings) and quality of life was measured with the previously validated SF-36 and newly created Hungarian SRI Questionnaires at two time points. Results One hundred four patients receiving home mechanical ventilation were enrolled. The time to complete the SRI Questionnaire was 8.6 (±3.1) minutes, 69.2% questionnaires were self-administered. Exploratory factor analysis explained 73.8% of the variance of the questionnaire, but resulted in 13 scales. We found correlations between the SRI subscale scores to corresponding scales of the previously validated general quality of life survey SF-36. The Cronbach alpha coefficient was 0.928 for the Summary Scale of the SRI Questionnaire, proving high internal consistency. Reproducibility was high for most scales, resulting in a high overall correlation for the summary score (0.877, p < 0.001). Conclusions The Hungarian version of the SRI Questionnaire is a viable, valid, reliable and reproduceable quality of life tool applicable for patients treated with home mechanical ventilation.