http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Choi, Hyeongsu,Lee, Jeongsu,Shin, Seokyoon,Lee, Juhyun,Lee, Seungjin,Park, Hyunwoo,Kwon, Sejin,Lee, Namgue,Bang, Minwook,Lee, Seung-Beck,Jeon, Hyeongtag IOP Pub 2018 Nanotechnology Vol.29 No.21
<P>Representative tin sulfide compounds, tin monosulfide (SnS) and tin disulfide (SnS<SUB>2</SUB>) are strong candidates for future nanoelectronic devices, based on non-toxicity, low cost, unique structures and optoelectronic properties. However, it is insufficient for synthesizing of tin sulfide thin films using vapor phase deposition method which is capable of fabricating reproducible device and securing high quality films, and their device characteristics. In this study, we obtained highly crystalline SnS thin films by atomic layer deposition and obtained highly crystalline SnS<SUB>2</SUB> thin films by phase transition of the SnS thin films. The SnS thin film was transformed into SnS<SUB>2</SUB> thin film by annealing at 450 °C for 1 h in H<SUB>2</SUB>S atmosphere. This phase transition was confirmed by x-ray diffractometer and x-ray photoelectron spectroscopy, and we studied the cause of the phase transition. We then compared the film characteristics of these two tin sulfide thin films and their switching device characteristics. SnS and SnS<SUB>2</SUB> thin films had optical bandgaps of 1.35 and 2.70 eV, and absorption coefficients of about 10<SUP>5</SUP> and 10<SUP>4</SUP> cm<SUP>−1</SUP> in the visible region, respectively. In addition, SnS and SnS<SUB>2</SUB> thin films exhibited p-type and n-type semiconductor characteristics. In the images of high resolution-transmission electron microscopy, SnS and SnS<SUB>2</SUB> directly showed a highly crystalline orthorhombic and hexagonal layered structure. The field effect transistors of SnS and SnS<SUB>2</SUB> thin films exhibited on–off drain current ratios of 8.8 and 2.1 × 10<SUP>3</SUP> and mobilities of 0.21 and 0.014 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP>, respectively. This difference in switching device characteristics mainly depends on the carrier concentration because it contributes to off-state conductance and mobility. The major carrier concentrations of the SnS and SnS<SUB>2</SUB> thin films were 6.0?×?10<SUP>16</SUP> and 8.7?×?10<SUP>13</SUP> cm<SUP>−3</SUP>, respectively, in this experiment.</P>
Lee, Soojin,Park, Sehoon,Kang, Min Woo,Yoo, Hai-Won,Han, Kyungdo,Kim, Yaerim,Lee, Jung Pyo,Joo, Kwon Wook,Lim, Chun Soo,Kim, Yon Su,Kim, Hyeongsu,Kim, Dong Ki Elsevier 2019 Journal of critical care Vol.50 No.-
<P><B>Abstract</B></P> <P><B>Purpose</B></P> <P>Dialysis-requiring acute kidney injury (AKI-D) after cardiac surgery is a major cause of in-hospital mortality. However, the long-term outcome has not been previously examined.</P> <P><B>Materials and methods</B></P> <P>We performed a nationwide, population-based cohort study using the claims data in the Korean National Health Insurance System. Patients who underwent cardiac surgery between 2006 and 2015 were considered.</P> <P><B>Results</B></P> <P>Among 52,983 patients who underwent cardiac surgery, 1261 underwent dialysis postoperatively. During the median follow-up of 3.33 years, the AKI-D group had increased risk of all-cause mortality, end-stage renal disease (ESRD) progression, and risk of developing major adverse cardiovascular events (MACEs). These results remained consistent after multivariable analysis and propensity-score matching. Even after excluding patients who continued dialysis at discharge, the AKI-D group consistently exhibited worse mortality and an increased risk of MACEs compared to the control group. Patients who underwent continuous renal replacement therapy in the AKI-D group exhibited comparable mortality and risk of MACEs but reduced progression to ESRD compared to those who received intermittent renal replacement therapy.</P> <P><B>Conclusions</B></P> <P>AKI-D following cardiac surgery was associated with worse long-term postdischarge mortality and elevated risks of dialysis dependency and MACE development. The outcomes were consistent even in the patients who recovered from the dialysis.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We examined the impact of dialysis-requiring AKI following cardiac surgery. </LI> <LI> AKI-D after cardiac surgery is associated with worse long-term prognosis. </LI> <LI> Postdischarge patients who recovered from AKI-D exhibited poor long-term outcomes. </LI> </UL> </P>
( Hyeongsu Lee ),( Se-ho Park ),( Jae-yeul Lee ),( Yuri Park ),( Hobin Jeong ),( Kwang-hwan Jhee ),( Daesuk Bang ) 한국고무학회 2016 엘라스토머 및 콤포지트 Vol.51 No.2
Polyvinyl chloride (PVC) has been used as a general-purpose polymer because of its lower cost, good durability and mechanical properties compared to other materials. However, PVC is vulnerable to heat deformation and generates a toxic gas like hydrogen chloride. Therefore, it is important to delay or prevent the flame retardancy and thermal degradation of the PVC during the processing. It was reported that aluminum trihydroxide (ATH) improved flame retardancy as well as smoke inhibition of the virgin polymer. In this study, PVC composites by addition of ATH were compounded in a modular intermeshing co-rotating twin screw extruder. The PVC composites with different concentrations of ATH (0~5 phr) were analyzed. Flame retardancy of the PVC composite significantly increased depending on the ATH concentration. LOI of the composite also increased with the concentration of ATH. There were no significant differences for the thermal properties of the PVC composites with ATH.
Lee Sang-Bin,Jeong Sunghyuk,Lee Hyobin,강예진,Lee Suseong,Jeong Na Ra,이재현,Park Sanghyo,Kim Jaewon,Han Inhyeok,Kim Hyeongsu,Kim Jaeyun,Seo Min Seok,Jo Chang Wook,Kim Soo Ji,Kwon Hyuk Nam,Cook Molly E.,Lim 한국응용곤충학회 2024 Journal of Asia-Pacific Entomology Vol.27 No.2
Incisitermes minor (Hagen), the western drywood termite, is an important structural pest in the US and has been introduced into other states such as Louisiana, Florida, and other countries as invasive species. Because of the cryptic nature of drywood termites, they can infest a piece of wood and can unintentionally be moved to different places on wooden materials such as in furniture. Recently, a drywood termite alate was collected by a citizen in Changwon, Republic of Korea, which has raised concerns if drywood termites were established in the nearby area. In order to initiate the management program, obtaining distribution range of the invasive drywood termite was necessary. Therefore, in this study, we surveyed the surrounding area within a 1 km radius from the initial alate collection site to detect any signs of drywood termite infestations and any active termite colony. Our morphological identification and molecular analysis using COI, COII, and 16s RNA confirmed that the collected termites were I. minor, and 16s RNA matched with I. minor from Japan and the USA. We found infestations in multiple structures in the surveyed area and a gazebo in the park that was heavily infested by I. minor, indicating that I. minor can overwinter in southern Korea. Due to the economic importance of I. minor, a management plan to prevent further spread and to minimize damage caused by I. minor is needed in Korea.
Lee, Namgue,Lee, Gunwoo,Choi, Hyeongsu,Park, Hyunwoo,Choi, Yeonsik,Kim, Keunsik,Choi, Yeongtae,Kim, Jong-Woo,Yuk, Hyunwoo,Sul, Onejae,Lee, Seung-Beck,Jeon, Hyeongtag Elsevier BV * North-Holland 2019 Applied Surface Science Vol.496 No.-
<P><B>Abstract</B></P> <P>In this report, two types of substrates were prepared for deposition of few-layer tin disulfide (SnS<SUB>2</SUB>) via atomic layer deposition (ALD). The first substrate was prepared using a conventional cleaning method, while the second substrate was rinsed with buffered oxide etcher (BOE) solution after conventional cleaning. Changes in the substrate were confirmed by X-ray photoelectron spectroscopy, contact angle measurements, and electron spin resonance. Characteristics of the SnS<SUB>2</SUB> thin films were determined by X-ray diffraction, Raman analysis, Fourier transform-infrared spectroscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. To investigate growth rate, thickness was measured as a function of ALD cycle number by atomic force microscopy, and 2D layered structure was confirmed by transmission electron microscopy. Findings confirmed that surface treatment using BOE solution was related to an increased growth rate during the initial ALD process. Finally, back-gate field effect transistors based on ALD-grown SnS<SUB>2</SUB> film prepared on substrate that received diluted-BOE surface treatment showed marginal improvement in current on/off ratio from 2.9 × 10<SUP>5</SUP> to 6.5 × 10<SUP>5</SUP> and mobility from 0.22 cm<SUP>2</SUP>/Vs to 0.31 cm<SUP>2</SUP>/Vs compared to ALD-grown SnS<SUB>2</SUB> film prepared on bare substrate.</P> <P><B>Highlights</B></P> <P> <UL> <LI> SnS<SUB>2</SUB> thin films were grown by atomic layer deposition. </LI> <LI> Bare and surface treated substrates were used to deposit SnS<SUB>2</SUB>. </LI> <LI> Buffered oxide etchant solution was used to surface treatment. </LI> <LI> Hydrophilicity of two different substrates was investigated. </LI> <LI> Growth rate and transport properties of SnS<SUB>2</SUB> thin films were investigated. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Juhyun Lee,Seokyoon Shin,Sejin Kwon,Woochool Jang,Hyeongsu Choi,Hyunwoo Park,Namgue Lee,전형탁 한양대학교 세라믹연구소 2021 Journal of Ceramic Processing Research Vol.22 No.3
Among various thin film encapsulation (TFE) methods, thin films prepared by atomic layer deposition (ALD) have been shownto provide superior protection against the permeation of moisture and oxygen. This technique has numerous of advantagessuch as excellent uniformity, precise thickness control, and strong adhesion. Therefore, with ozone-based ALD, we conductedthe influence of the thickness of aluminum oxide (Al2O3) on moisture barrier properties. From the results of an electricalcalcium test, Al2O3 had two distinctly different permeation regimes. Between 10 and 25 nm of Al2O3 thickness, the water vaportransmission rate (WVTR) decreased exponentially from 6.3 × 10−3 to 1.0 × 10−4 g m−2 day−1 (1/60 times). In contrast, asthickness increased from 25 to 100 nm, the WVTR values decreased by only two-thirds, from 1.0 × 10−4 to 6.6 × 10−5 g·m−2·day−1. Tobetter understand the change from an exponential to a sub-exponential regime, defect density and refractive index of Al2O3were measured. The thickness dependence on defect density and refractive index was analogous with one of moisture barrierperformance. These results confirmed the existence of a critical thickness at which the WVTR decreased drastically.
이동길(Donggil LEE),배봉성(Bongseong BAE),이정호(Jeong-Ho LEE),김석태(Sugtai KIM),김형수(Hyeongsu KIM) 한국수산해양교육학회 2021 水産海洋敎育硏究 Vol.33 No.2
Global marine fisheries resources are showing decreasing trends due to the overfishing and the climate change, and the seafood deficit by the fisheries is replaced by the products from aquaculture industries. However, the aquaculture industry in Korea is experiencing the negative consequences by the decreasing and aging population of fishing village, and the natural disaster such as annual algal blooms (red tide) and abnormally high water temperatures phenomena. The academia and industry of aquaculture are conducting research on the smart aquaculture technology that combines the 4th industrial revolution technologies such as information and communication technology and artificial intelligence (AI) technology to resolve the current difficulties of the aquaculture industries and to secure stable and sustainable aquaculture technologies of the organisms. However, it is not clear to define the concept and definition of the smart or advanced aquaculture technology since it is a new research subject in Korea. Also, there would be diverse ways to develop it. In this study, we suggest the methods how to approach and industrialize on the smart aquaculture technology for the Korean aquaculture environments and management structures. The methods aimed to reduce risks and to stabilize the adaptation process of the smart aquaculture technology.