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Minimum quantity lubrication (MQL) with carbon nanostructured additives in sheet metal forming

This work is an experimental study covering minimum quantity lubrication (MQL) in sheet metal forming. Two different lubricants have been studied. Nanosized graphite platelets (GnP) has been tested as additives to the base oils in order to improve the lubricant performance. The experiments have been performed utilizing a laboratory tribotester based on strip drawing. Friction measurements have bee

Influence of GnP additive to vegetable oil on machining performance when MQL-assisted turning Alloy 718

The current study demonstrates through experiment the effect of solid lubricant assisted minimum quantity lubrication (MQL) on the machining performance when turning Alloy 718 with cemented carbide tools. A powder of nanosized (~30 nm) graphite nanoplatelets (GnP) was dispersed (0.2% vol.) in a vegetable oil-based lubricant “ECOLUBRIC E200L” and used in MQL-assisted machining. The effect of cuttin

Application of Colding tool life equation on the drilling fiber reinforcement polymers

Fiber reinforcement polymer (FRP) is a hard-to-treat material used in different areas of up-to-date machine building. It has excellent mechanical properties making the material unique in different engineering solutions such as aircraft, aerospace and boatbuilding. The optimization of holemaking operations in FRP is the main aim of the current investigation. This paper presents an approach of definFiber reinforcement polymer (FRP) is a hard-to-treat material used in different areas of up-to-date machine building. It has excellent mechanical properties making the material unique in different engineering solutions such as aircraft, aerospace and boatbuilding. The optimization of holemaking operations in FRP is the main aim of the current investigation. This paper presents an approach of defin

Leading towards high-performance manufacturing - Enabling indicators in early R&D phases ensuring future KPI outcome

Key Performance Indicators (KPIs) are not only essential during manufacturing operations. Also during the development phases of product and manufacturing system, where future performance of the operational order-to-delivery-process is set, KPIs are important to consider. This paper introduces "enabling indicators" that can be analyzed or assessed in early phases of product and manufacturing develo

EPA – en modell för att träna och bedöma dagligt läkarjobb

EPA (entrustable professional activities) avser aktiviteter som ingår i en läkares dagliga arbete och som läkaren ska klara med en definierad grad av självständighet första dagen som legitimerad läkare.En modell för att träna och bedöma sådana aktiviteter kan säkerställa att studenter klarar av det faktiska arbete som ska utföras första dagen efter legitimation, och den tydliggör också progressionEntrustable Professional Activities (EPAs) define observable key tasks that a doctor should be able to do independently after having completed a certain level of education. Progression is facilitated by frequent assessments of the defined activities, with increased degree of independence. The observations should be supported by constructive feed-forward. EPA is currently used in several countries

Enzymatic conversions of polar lipids. Principles, problems and solutions

This text provides a brief overview of the principles of enzymatic lipid conversion and some recent advances in the enzymatic conversion of glycerophospholipids and galactolipids. Lipases and phospholipases are used to exchange fatty acids or the polar group in the lipids. The reactions can be carried out either as hydrolysis-esterification sequences or as one-step transferase reactions. The scope

A kinetic study of almond-β-glucosidase catalysed synthesis of hexyl-glycosides in low aqueous media : Influence of glycosyl donor and water activity

A variety of alkyl and aryl glycosides were investigated as substrates for almond β-glucosidase catalysed synthesis of hexyl-β-D-glycosides in low aqueous hexanol media. The rate-limiting step in the organic media was determined to be the glycosylation of the enzyme. The kinetic constants V max , K m (glycosyl donor) and V max /K m were all influenced by the water activity and they all increased

Influence of water activity on the competition between β-glycosidase-catalysed transglycosylation and hydrolysis in aqueous hexanol

Five different β-glycosidases (Pyrococcus furiosus β-glucosidase, Sulfolobus solfataricus β-galactosidase, Caldocellum saccharolyticum β-glucosidase, almond β-glucosidase and Escherichia coli β-galactosidase) were evaluated as transglycosylation catalysts in hexanol containing various amounts of water. All enzymes catalysed both hydrolysis and transglycosylation of the glycosidic substrates (penty

Thermodynamic and kinetic aspects on water vs. organic solvent as reaction media in the enzyme-catalysed reduction of ketones

The stereoselective reduction of ketones catalysed by alcohol dehydrogenase from Thermoanaerobium brockii was studied in different reaction media, hexane at controlled water activities, hexane with 2.5% water (biphasic) and pure water. The reactions were studied in the temperature range from -1 to 50°C. Increasing the water activity from 0.53 to 0.97 increased the reaction rate 16-fold. The rate w