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“New Way to Combat Super Bacteria: Nano-Antibiotic Mixed with Metal Ion”
2022-09-21 OTHER
More표시내용“New Way to Combat Super Bacteria: Nano-Antibiotic Mixed with Metal Ion is it oaky
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New Treatment Possibility for Metabolic Syndrome through Korean Medicine Using Seaweed Kelp
2022-09-21 ACADEMIC
MoreProfessor Bonglee Kim at the College of Korean Medicine and his research team discovered a promising treatment possibility for metabolic syndrome using the herbal medicine Konpo (Laminaria Japonica), commonly known as kelp
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Development of New Sustainable Iron-based Metal Photocatalysis Technology for Carbon Cyclohexenes Synthesis
2022-08-29 RESEARCH
MoreDevelopment of New Sustainable Iron-based Metal Photocatalysis Technology for Carbon Cyclohexenes Synthesis
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New Wireless Charging Technology Works Even in a Moving Environment
2022-08-03
Professor Sanghoek Kim at the Department of Electronic Engineering and his team developed a high-efficiency wireless power transfer system The convenience of recharging devices wirelessly is driving this technology to become more common in everyday life. Wireless charging technology is about generating magnetic resonance between the transmission side (TX) and the receiver end (RX) to transmit power and charge batteries without the need for a connecting cable. However, wireless charging has limited range and is sensitive to changing locations or circumstances, requiring most devices to remain stationary on a special pad or surface while being recharged. Professors Sanghoek Kim and Dae-Hyeong Kim of Seoul National University joined forces to develop a highly efficient wireless power transfer system that can charge up devices while they are in motion. Student Hyunwoo Kim, who was part of the research team, explained, “The technology that transmits power to devices a few meters away using magnetic resonance has been around since the beginning of wireless power transmission, but problems with maintaining charging stability have made commercialization difficult.” Power transmission efficiency drops when the distance between the TX and RX changes or the either of the devices moves. Recently, researchers have devised a new solution by attaching multiple transmitting coils to a wireless power transfer (WPT) system. However, coils, which helped to widen the power transmission range, typically need expensive power amplifiers and phase converters for voltage and phase adjustment. Also, they have failed to support charging devices that are in motion. Professor Kim and his team proposed a technique that can control the voltage and phase of coils without a power amplifier and a phase converter. The researchers attached a variable capacitor to the coil, which enabled them to design a WPT system with parity-time symmetry. He explained, “Being in parity-time symmetry generates resonant frequencies.” Controlling the variable capacitor to generate resonant frequencies causes all coils attached to the WPT system to resonate, yielding high transmission efficiency. The proposed system is optimized only by adjusting the storage capacity corresponding to the changing conditions, enabling stable transmission even in a dynamic environment. Student Seungwon Yoo of Seoul National University, who was a team member, stressed: “Using three coils while adjusting the capacitance widens the operational range twenty-fold compared with using one coil. The more coils, the wider the transmission range. A system configuration without expensive power amplifiers and phase converters significantly lowered the production cost.” Charging devices in motion without cables can be applied to medical devices including medical implants. Implanted devices tend to have poor power transmission efficiency due to uncertainties in their in vivo environments. To prove that the technology can be applied to biomedical implants, the researchers installed a receiver inside a skin-like flexible device and confirmed that power is transmitted over a wide range even in a dynamic environment. Professor Kim said: “The expertise in biomedical wearables of Professor Dae-Hyeong Kim’s research team enabled us to overcome the difficulties we had previously encountered. We plan to build a system that can monitor electrical stimulation on the heart’s surface with the help of multiple electrodes placed directly on the heart.”More -
Increasing Electrical Output by Fifty Times with Everyday Item Such as Sponge
2022-08-03
Professor Dongwhi Choi and his team at the Department of Mechanical Engineering has found a new way to significantly improve the sensitivity of droplet-based triboelectric sensors A simple sponges seen in everyday use could amplify electric signals, which was confirmed in experiments by Professor Choi and his team. Their research set off when they incidentally observed water droplets amplifying electric signals while soaking into a tissue paper. Droplets being absorbed into the porous cellulose membrane caused a liquid flow phenomenon, creating an environment where electric charges move faster and more often, thereby increasing the electrical signal output. Professor Choi joined up with Professors Zong-Hong Lin of National Tsing Hua University, Taiwan, and Dahoon Ahn of Seoul National University of Science and Technology. Their research outcome decorated the front cover of Nano Energy magazine (IF 17.881, JCR 4.64%) published on June 16, 2022. While triboelectricity has high voltage, it also has low amperage, so fortunately its harm to human touch is limited. With this high-voltage/low-current characteristic, triboelectricity came into the spotlight as the main source of energy harvesting, a technology for collecting energy from everyday sources ignored previously. Triboelectricity is commonly believed to be created only when two solid surfaces contact, but it is generated even when a solid and a liquid meet. However, solid-liquid interface usually generates much smaller amount of electricity compared to solid-solid contact. Although the energy amount generated from each contact is negligibly small, abundant contact opportunities such as raindrops and waves, and easy access to harvesting have spurred research on droplet-based triboelectric nanogenerators. Professor Choi’s team employed a sponge to overcome the limitations from the minute amount of triboelectricity generated between a liquid and a solid. They then proposed how their method could be applied further. Professor Choi explained, “It was a mere sponge that amplified electric signals by 50 times.” Student Sunmin Jang added, “Most researchers had paid attention to increasing the production of electric charge. Our research is the world’s first to amplify the current with the focus on the movement of electric charge.” Numerous studies have sought to increase the electric charge by modifying the element surface, but Professor Choi’s research team has offered a solution by concentrating on the movement of the charge. The sponge employed in the study continued to generate stable signals even after about 10,000 uses. A self-powered sensor module was also developed. According to the research leader: “The sensor is one of the key application methods for droplet-based triboelectric nanogenerators (TENGs). Our sensor module works corresponding to the electric signal amplified by the sponge. The sensor detects the concentration of electrolytes contained in droplets or the acidity of raindrops and transmits the analysis without cables to your mobile phone.” The researchers plan to continue their follow-up study with the findings gained this time from the practical application of the droplet-based TENG. Professor Choi said, “We were able to amplify the electric signals with the help of the porous cellulose membrane, which should eventually be removed without any interruption in the improved output of droplet-based TENGs. With a dramatically significant increase in electrical signals, the TENG will play its role as an energy harvester.” Jang said, “I plan to find ways to increase the output of droplet-based TENG. I will not confine my research to sensors and continue to develop platforms that can use electric signals in many other ways.”More
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“New Way to Combat Super Bacteria: Nano-Antibiotic Mixed with Metal Ion”
2022-09-21
Professor Kim Dokyoung of the College of Medicine proposed the world’s first nano-antibiotic development strategy that can overcome super bacteria “Super Bacteria,” also known as “Super Bug,” are resistant to antibiotics and notoriously difficult to treat. In early 2020, in a special report analyzing the progress of new antibiotics in the development pipeline, the World Health Organization (WHO) urged global pharmaceutical companies to ramp up their effort to fi...
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New Treatment Possibility for Metabolic Syndrome through Korean Medicine Using Seaweed Kelp
2022-09-21
Professor Bonglee Kim at the College of Korean Medicine and his research team discovered a promising treatment possibility for metabolic syndrome using the herbal medicine Konpo (Laminaria Japonica), commonly known as kelp Konpo is a popular ingredient in a variety of food, which is known to have the effect of purifying the blood. Metabolic syndrome refers to a distinctive group of pathological conditions including abdominal obesity, insulin resistance, hypertension, and hyperlipidemia appea...
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