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排序方式: 共有3723条查询结果,搜索用时 31 毫秒
1.
Young Been Kim Sung Hyeon Jung Dong Su Kim Nishad G. Deshpande Hee Won Suh Hak Hyeon Lee Ji Hoon Choi Ho Seong Lee Hyung Koun Cho 《Advanced functional materials》2021,31(38):2102439
Antimony triselenide (Sb2Se3) nanoflake-based nitrogen dioxide (NO2) sensors exhibit a progressive bifunctional gas-sensing performance, with a rapid alarm for hazardous highly concentrated gases, and an advanced memory-type function for low-concentration (<1 ppm) monitoring repeated under potentially fatal exposure. Rectangular and cuboid shaped Sb2Se3 nanoflakes, comprising van der Waals planes with large surface areas and covalent bond planes with small areas, can rapidly detect a wide range of NO2 gas concentrations from 0.1 to 100 ppm. These Sb2Se3 nanoflakes are found to be suitable for physisorption-based gas sensing owing to their anisotropic quasi-2D crystal structure with extremely enlarged van der Waals planes, where they are humidity-insensitive and consequently exhibit an extremely stable baseline current. The Sb2Se3 nanoflake sensor exhibits a room-temperature/low-voltage operation, which is noticeable owing to its low energy consumption and rapid response even under a NO2 gas flow of only 1 ppm. As a result, the Sb2Se3 nanoflake sensor is suitable for the development of a rapid alarm system. Furthermore, the persistent gas-sensing conductivity of the sensor with a slow decaying current can enable the development of a progressive memory-type sensor that retains the previous signal under irregular gas injection at low concentrations. 相似文献
2.
Seulah Lee Yeon Ji Suh Seonguk Yang Dong Geun Hong Akihito Ishigami Hangun Kim Jae-Seoun Hur Seung-Cheol Chang Jaewon Lee 《International journal of molecular sciences》2021,22(4)
Oxidative stress, mitochondrial dysfunction, and neuroinflammation are strongly associated with the pathogenesis of Parkinson’s disease (PD), which suggests that anti-oxidative and anti-inflammatory compounds might provide an alternative treatment for PD. Here, we evaluated the neuroprotective effects of evernic aid (EA), which was screened from a lichen library provided by the Korean Lichen Research Institute at Sunchon National University. EA is a secondary metabolite generated by lichens, including Ramalina, Evernia, and Hypogymnia, and several studies have described its anticancer, antifungal, and antimicrobial effects. However, the neuroprotective effects of EA have not been studied. We found that EA protected primary cultured neurons against 1-methyl-4-phenylpyridium (MPP+)-induced cell death, mitochondrial dysfunction, and oxidative stress, and effectively reduced MPP+-induced astroglial activation by inhibiting the NF-κB pathway. In vivo, EA ameliorated MPTP-induced motor dysfunction, dopaminergic neuronal loss, and neuroinflammation in the nigrostriatal pathway in C57BL/6 mice. Taken together, our findings demonstrate that EA has neuroprotective and anti-inflammatory effects in PD models and suggest that EA is a potential therapeutic candidate for PD. 相似文献
3.
B. Purusottam Reddy M. Chandra Sekhar B. Poorna Prakash Youngsuk Suh Si-Hyun Park 《Ceramics International》2018,44(16):19512-19521
We successfully prepared La1?xBixFeO3 (LxB1?xFO, x?=?0.01–0.1) nanoparticles using a sol-gel technique, and studied their photocatalytic, magnetic, and electrochemical properties. Structural refinement studies of the prepared nanoparticles revealed a gradual structural transition from rhombohedral to orthorhombic. The average grain size was observed to decrease with increasing the concentration of La. The photocatalytic degradation of Rhodamine B (RhB) in the presence of the prepared nanoparticles was studied under visible light irradiation. The L0.06B0.94FO nanoparticles showed higher degradation efficiency compared to pure BiFeO3 (BFO) nanoparticles. Magnetic studies showed that La doping improved the magnetization of BFO due to the reduction in grain size and destruction of cycloid coupling of spins. Higher specific capacitance values were obtained for La doped BFO (LBFO) nanoparticles compared to BFO nanoparticles. A maximum specific capacitance of 219?F?g?1 was obtained at a current density of 1?A?g?1 for LBFO nanoparticles. 相似文献
4.
Hong Heerok Lee Hoyong Jeong Naktak Baek Keonhee Suh Myungwon 《Journal of Mechanical Science and Technology》2020,34(3):1195-1205
Journal of Mechanical Science and Technology - The threaded fasteners are typical machine components in tightening of the machine parts and structures. In addition, as threaded fasteners are easy... 相似文献
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Hong Heerok Kim Gyeongpil Lee Hoyong Kim Jaesik Lee Dasom Kim Minsoo Suh Myungwon Lee Junghwan 《Journal of Mechanical Science and Technology》2021,35(3):1109-1120
Journal of Mechanical Science and Technology - During the braking process, frictional heat generated between a disc and a pad can lead to high temperatures. The location of friction blocks on the... 相似文献
9.
Inpainting has been continuously studied in the field of computer
vision. As artificial intelligence technology developed, deep learning technology
was introduced in inpainting research, helping to improve performance. Currently,
the input target of an inpainting algorithm using deep learning has been studied
from a single image to a video. However, deep learning-based inpainting technology for panoramic images has not been actively studied. We propose a 360-degree
panoramic image inpainting method using generative adversarial networks
(GANs). The proposed network inputs a 360-degree equirectangular format
panoramic image converts it into a cube map format, which has relatively little
distortion and uses it as a training network. Since the cube map format is used,
the correlation of the six sides of the cube map should be considered. Therefore,
all faces of the cube map are used as input for the whole discriminative network,
and each face of the cube map is used as input for the slice discriminative network
to determine the authenticity of the generated image. The proposed network performed qualitatively better than existing single-image inpainting algorithms and
baseline algorithms. 相似文献
10.
Two types of degradable poly(propylene glycol) (PPG) hydrogels that are suitable for the absorption of heavy metals have been presented. The PPG‐O‐P(O)Cl2 fragments obtained by treating hexafunctional PPG with phosphorous oxychloride (POCl3) react with 1,3‐propanediamine (PDA; Gel‐1 ) or PDA together with 1,2‐ethanedithiol ( Gel‐2 ), to yield cross‐linked and water‐swellable hydrogels in a one‐pot method. This protocol for the fabrication of PPG hydrogels exhibits promising advantages over prior methods including a short reaction time, mass‐production, easy separation, and high yield. A series of heavy metal ions were employed to test the adsorptive properties of the hydrogels. Gel‐2 shows better adsorption capacity than Gel‐1 for all the metal ions and the metal ions adsorption efficiency of the two types of hydrogels is in the order of Fe(III) > Pb(II) > Cd(II) > Zn(II) > Cu(II) > Ni(II) > Co(II) > Hg(II). The amounts of metal ions adsorbed increases with metal ion concentration and hydrogel dosage, but decreases with temperature. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40610. 相似文献