Kwangwoon University

About: Kwangwoon University is a education organization based out in Seoul, South Korea. It is known for research contribution in the topics: Thin film & Resonator. The organization has 4020 authors who have published 8217 publications receiving 104365 citations.

Plain to point network reduced graphene oxide-activated carbon composites decorated with platinum nanoparticles for urine glucose detection.

Abstract: In this study, a hydrothermal technique was applied to synthesize glucose-treated reduced graphene oxide-activated carbon (GRGO/AC) composites. Platinum nanoparticles (PtNP) were electrochemically deposited on the modified GRGO/AC surface, and chitosan-glucose oxidase (Chit-GOx) composites and nafion were integrated onto the modified surface of the working electrode to prepare a highly sensitive glucose sensor. The fabricated biosensor exhibited a good amperometric response to glucose in the detection range from 0.002 mM to 10 mM, with a sensitivity of 61.06 μA/mMcm2, a short response time (4 s) and a low detection limit of 2 μM (signal to noise ratio is 3). The glucose sensor exhibited a negligible response to interference and good stability. In addition, the glucose levels in human urine were tested in order to conduct a practical assessment of the proposed sensor, and the results indicate that the sensor had superior urine glucose recognition. These results thus demonstrate that the noble nano-structured electrode with a high surface area and electrocatalytic activity offers great promise for use in urine glucose sensing applications.

Micro-Fabricated Electromagnetic Power Generator to Scavenge Low Ambient Vibration

Abstract: In this paper, micro-fabricated electromagnetic power generator is presented to convert the low level ambient vibration into electric energy. The proposed micro-power generator is comprised of three micro-components such as bulk-micromachined silicon spiral spring, low loss copper micro-coil, and NdFeB magnet to be assembled with low cost PDMS packaging substrate. In order to maximize the output power, magnet is applied as inertial mass at the center of silicon spiral spring to adjust its resonant frequency. Especially, NdFeB discrete/miniaturized magnet and copper wire wounded micro-coil were utilized to avoid the performance deterioration of the proposed device due to its miniaturization. It was specially designed for scavenging low ambient vibration of several tens of hertz and low acceleration under 1g. The fabricated device generated output power of 115.1 W and load voltage of 68.2 mV to the load resistance of 18.1 from the vibration of 54 Hz with acceleration of 0.57 g. The normalized power density was 590.4 ?W/cm3g2.

Deoxygenation of Sulfoxides to Sulfides with Thionyl Chloride and Triphenylphosphine: Competition with the Pummerer Reaction

Abstract: Although a number of methods have been developed to reduce sulfoxides to sulfides, many of these processes are limited by side reactions, low yields, poorly available reagents, or harsh reaction conditions. We recently studied the reaction of various sulfoxides with SOCl2 and Ph3P. We were able to obtain the corresponding sulfides in excellent yields (>90%) when aliphatic and aromatic sulfoxides were treated with SOCl2 as a catalyst and Ph3P in THF at room temperature.

Measurement of human heartbeat and respiration signals using phase detection radar.

Abstract: This article introduces a low-cost phase detection radar aimed at measuring the human heartbeat and respiration signals without any physical connections to the human body. A continuous-wave radar targeting the chest will detect the phase difference, resulted by the time-varying target position of the heartbeat, between the transmitted signal and the reflected signal. We have tested the developed radar to measure the heartbeat and respiration signals at a distance of about 40 cm from the chest.