Cadaverine (1,5-diaminopentane) is a major source of many industrial polyamides such as nylon and chelating agents. Currently, cadaverine is produced by the microbial fermentation of glucose to lysine, which is then decarboxylated by lysine decarboxylase (CadA). However, utilizing CadA for cadaverine production causes enzyme instability. In order to stabilize the CadA homo-decamer structure for in vitro decarboxylation reaction, mutants are designed. Of the four disulfide bond mutants in the multimeric interfacial region, B1 (F14C/K44C) showed a 216-folds increase in the half-life of CadA at 60 °C. On top of B1, another round of mutant screening is performed around F14C and K44C to generate B1/L7M/N8G, which is then examined for cadaverine production (2M lysine and 10% v/v of cell-extract at 50 °C). The reaction pH increased from 4.9 to 8.3, and the final titer of the mutant is 157 g L , that is, 76.7% conversion yield in 9.5 h, whereas the wild-type gave 119 g L , that is, 58.2% conversion yield in 9.5 h.

From graphene oxide wrapped iron oxide particles with etching/reduction process, high-performance anode and cathode materials of lithium-ion hybrid supercapacitors are obtained in the same process with different etching conditions, which consist of partially etched crumpled graphene (CG) wrapped spiky iron oxide particles (CG@SF) for a battery-type anode, and fully etched CG for a capacitive-type cathode. The CG is formed along the shape of spikily etched particles, resulting in high specific surface area and electrical conductivity, thus the CG-based cathode exhibits remarkable capacitive performance of 210 F g and excellent rate capabilities. The CG@SF can also be ideal anode materials owing to spiky and porous morphology of the particles and tightly attached crumpled graphene onto the spiky particles, which provides structural stability and low contact resistance during repetitive lithiation/delithiation processes. The CG@SF anode shows a particularly high capacitive performance of 1420 mAh g after 270 cycles, continuously increases capacity beyond the 270th cycle, and also maintains a high capacity of 170 mAh g at extremely high speeds of 100 C. The full-cell exhibits a higher energy density up to 121 Wh kg and maintains high energy density of 60.1 Wh kg at 18.0 kW kg . This system could thus be a practical energy storage system to fill the gap between batteries and supercapacitors.

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A deep trench isolation (DTI) process with a 4 µm deep trench has been developed and successfully applied to 5-megapixel complementary metal oxide silicon (CMOS) image sensors with a 1.7 µm pixel pitch. It was found that from the results of simulations and experiments, DTI is very effective for reducing electrical crosstalk without degrading other pixel characteristics, such as full well capacity, sensitivity, and white spot density. Therefore, DTI could be a solution for obtaining a high performance for CMOS image sensors with a small pixel size of sub-2.0 µm.

To achieve the zero-carbon-emissions society, it is essential to increase the use of clean and renewable energy. Yet, renewable energy resources present constraints in terms of geographical locations and limited...