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The activity and selectivity of W110G Thermoanaerobacter ethanolicus secondary alcohol dehydrogenase were altered by cosubstrate and cosolvent at varying temperature. A sharp drop in the enantiomeric excess (ee) was observed at 60 oC in the first 3 h suggesting increased selectivity mistakes in the reduction of 4-phenyl-2-butanone to the expected (¬S)-4-phenyl-2-butanol using 5% v/v of 2-propanol as a cosubstrate. The ee increased exponentially with cosubstrate concentration reaching ≥94% with 30-70% v/v 2-propanol. A drop in enzyme activity was however noticed at ≥30% v/v 2-propanol by a sharp drop in conversion. The lowest ee (<3%) was registered using 5% v/v 2-propanol at 30-40 oC which prolonged enzyme life that allowed reversible redox reaction with selectivity mistakes to give the R-alcohol compared to ≥18% ee at 50-60 oC where faster reaction rates promote selectivity mistake but enzyme life is shortened by protein denaturation at the elevated temperatures. Water-miscible and immiscible organic cosolvents (25% v/v) increased enzyme selectivity. For methanol, ethanol, ethylene glycol and tert-butanol, the activity/conversion decreased with an increase in pKa and log P while the stereoselectivity/ee increased.

In this study, the metal coordination ability of alpha-cyclodextrin (α-CD) was employed to complex gold and thus isolate and extract it from different matrices of acid-digests of electronic waste and soil. The crude α-CD used was extracted from cassava and yam starch of the non-edible plant species using E. coli α-cyclodextrin glucanotransferase (α-CGTase), with yields ≥ 62%. The reaction was monitored progressively by ultraviolet-visible spectroscopy and checked with infrared spectroscopy (IR) for the presence of α-CD. The crude α-CD extract without need for purification was refluxed with gold containing-electronic waste and soil predigested in a mixture of NaBr/HNO 3 for 4 -7 days. Recoveries of up to 22.9% and 70.8% gold were achieved from electronic waste and soil, respectively using 0.1 M α-CD. This approach is cheap, effective, and environmentally benign.

<p>In order to maximize power production, wind turbines (WTs) are continuously emerging as bigger and taller structures, built in more challenging environments. This development however decreases the reliability of wind turbine (WT) infrastructures. In addition, the dynamic nature of the loads typical for WT structures result in an excessive number of stress cycles during their operation lifetime. This might significantly differ from the fatigue loading design assumptions, which is a determinant factor for limiting the design lifetime of WTs to a minimum target period of 20 years.</p><p>Installed Structural Health Monitoring (SHM) system on an operating WT structure provides invaluable insight to the structural performance and can contribute to early damage detection, thus eventually leading to reduced maintenance costs and extension of operation life time. In this paper, a four- year continuously recorded SHM data of an Enercon E40 - 500 kW type WT is utilized for assessing its consumed fatigue life time at a welded connection. The monitoring system was implemented on the WT located in Dortmund, Germany, as part of a DFG-funded research project with cooperation to Ruhr-University Bochum.</p>