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^(27)Al MAS-NMR study of inorganic polymer formation at ambient temperature

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 182-187页

作者： Sang-Wook AHN hee-Soo LEE Wan-hee YANG Jung-Woo LEE young-Keun JEONG National Core Research Center for Hybrid Materials Solution Pusan National University School of Material Science and Engineering Pusan National University INTChem Co. Ltd.

Inorganic polymers are a novel class of materials formed by the polymerization of silicon, aluminium and oxygen species to form an amorphous three-dimensional framework structure. The basis of this process is the alkaline solutions to induce a certain amount of Si and AI atoms to dissolve from a feedstock such as aluminosilicate. A study of 27A1 MAS-NMR was carried out in an attempt to understand the reaction mechanism of the inorganic polymerization at ambient temperature. Scanning electron microscopy （SEM） and X-ray diflYactometry （XRD） were also employed to establish the composition and microstructure of the inorganic polymerization. Specimens were prepared with different A1/Si mole ratios from the starting materials. The higher the AI content, the more sufficient the AI atoms that can combine with SiO4, and the longer the reaction time, the more the bonded Si--O--A1--O polymer structure, and then the higher the A1 content, the fewer the octahedral A1 with a uniform Si--O--A1--O structure in four directions, because four AI atoms are combined with SiO4, resulting in a uniform Si--O--AI--O structure in four directions. The results show that they have an amorphous microstructure.

关键词： inorganic polymer amorphous tetrahedral

Comparable electrocatalytic performances of carbon-and Rh-loaded SrTiO_3 nanoparticles

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Chinese Chemical Letters 2018年第6期29卷 800-804页

作者： hee Jung yoon Seog K.Kim Weixin Huang youngku Sohn Department of Chemistry Yeungnam University Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Materials for Energy Conversion Department of Chemical PhysicsUniversity of Science and Technology of China Department of Chemistry Chungnam National University

Carbon-and Rh-loaded strontium titanate（SrTiO3） nanoparticles（NPs） were synthesized respectively by the wet impregnation method and the aerobic and anaerobic ethanol oxidation methods, and characterized by scanning electron microscopy, high resolution transmission electron microscopy, X-ray diffraction crystallography, UV–vis absorption, Raman spectroscopy, and X-ray photoelectron spectroscopy. Carbon was shown to be uniformly coated on SrTiO3 NPs by the aerobic and anaerobic ethanol oxidation methods Electrocatalytic activities of unmodified and modified SrTiO3 NPs were tested for water splitting and CO2 reduction. The aerobic C-coated and Rh-loaded SrTiO3 catalysts showed comparable activity that was increased by 〉10-fold of that of unmodified SrTiO3 catalyst. These results demonstrate that both metallic and nonmetallic surface modifications can highly improve the electrocatalytic activity of SrTiO3 NPs and point to highlight a more important role of the modifier in the electrocatalytic reactions than of the SrTiO3 structure.

关键词： SrTiO3 Carbon Rhodium Ethanol oxidation Electrocatalytic water splitting Electrocatalytic CO2 reduction

Identification of Aristolactam Derivatives That Act as Inhibitors of Human Immunodeficiency Virus Type 1 Infection and Replication by Targeting Tat-Mediated Viral Transcription

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Virologica Sinica 2021年第2期36卷 254-263页

作者： young Hyun Shin Chul Min Park Hong Gi Kim Dong-Eun Kim Min Suk Choi Jeong-ah Kim Byeong-Sun Choi Cheol-hee yoon Division of Viral Disease Research Center for Infectious Disease ResearchKorea National Institute of HealthHeungdeok-guCheongju-siShungbuk 28159Republic of Korea Center for Convergent Research of Emerging Virus Infection Korea Research Institute of Chemical TechnologyYuseong-guDaejeon 34114Republic of Korea

Despite the success of antiretroviral therapy(ART),efforts to develop new classes of antiviral agents have been hampered by the emergence of drug ***-indole-bearing aristolactams are compounds that have been isolated from various plants species and which show several clinically relevant effects,including anti-inflammatory,antiplatelet,and antimycobacterial ***,the effect of these compounds on human immunodeficiency virus type 1(HIV-1)infection has not yet been *** this study,we discovered an aristolactam derivative bearing dibenzo[cd,f]indol-4(5 H)-one that had a potent anti-HIV-1 effect.A structure-activity relationship(SAR)study using nine synthetic derivatives of aristolactam identified the differing effects of residue substitutions on the inhibition of HIV-1 infection and cell *** the compounds tested,1,2,8,9-tetramethoxy-5-(2-(piperidin-1-yl)ethyl)-dibenzo[cd,f]indol-4(5 H)-one(Compound 2)exhibited the most potent activity by inhibiting HIV-1 infection with a half-maximal inhibitory concentration(IC50)of 1.03 lmol/L and a half-maximal cytotoxic concentration(CC50)of 16.91 lmol/L(selectivity index,16.45).The inhibitory effect of the compounds on HIV-1 infection was linked to inhibition of the viral replication ***-of-action studies showed that the aristolactam derivatives did not affect reverse transcription or integration;instead,they specifically inhibited Tat-mediated viral *** together,these findings show that several aristolactam derivatives impaired HIV-1 infection by inhibiting the activity of Tat-mediated viral transcription,and suggest that these derivatives could be antiviral drug candidates.

关键词： Human immunodeficiency virus type 1(HIV-1) Aristolactam Antiviral activity HIV-1 transcription

Pilomatrixoma of the upper eyelid in a 10-month-old baby

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International Journal of Ophthalmology(English edition) 2019年第9期12卷 1510-1513页

作者： Jungyul Park Hyeshin Jeon hee-young Choi Department of Ophthalmology Pusan National University HospitalBusan 49241Korea Biomedical Research Institute Pusan National University HospitalBusan 49241Korea

Dear Editor,I am Dr. Jungyul Park from the Division of Oculoplasty,Department of Ophthalmology,Pusan National University Hospital, Busan, Korea. I am writing to present a case of pilomatrixoma of the upper eyelid in a... 详细信息

关键词： red Pilomatrixoma 10-month-old baby

Thin film processing and multiferroic properties of Fe-BaTiO_3 hybrid composite

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 92-95页

作者： Pan YANG Jin-song ZHU Jai-Yeoul LEE hee young LEE School of Materials Science and Engineering Yeungnam University Gyeongsan 712-749 Korea National Laboratory of Solid State Microstructures Department of Physics Nanjing University Nanjing 210093 China

Multiferroic bi-layer Fe/BaTiO3 （BTO） thin films were successfully deposited on Pt（200）/MgO（100） substrates using ion beam sputter deposition （1BSD）, and the mutiferroic properties were studied at room temperature. X-ray diffraction （XRD） analyses showed that BTO films were c-axis oriented and epitaxially grown on platinum coated MgO substrates, and （110） epitaxial Fe films were subsequently grown on （001） BTO films. Fe/BTO bi-layer films showed good ferroelectric and ferromagnetic properties at room temperature and the multiferroic coupling was observed, which should be attributed to the hybridization of Fe and Ti occurring at the ferromagnetic-ferroelectric interface.

关键词： multiferroic effect ferroelectricity magnetic properties magnetoelectric effect

Undetected traumatic cardiac herniation like playing hide-and-seek-delayed incidental findings during surgical stabilization of flail chest:A case report

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World Journal of Clinical Cases 2022年第36期10卷 13396-13401页

作者： Su young yoon Jin-Bong Ye Junepill Seok Department of Thoracic and Cardiovascular Surgery Chungbuk National University HospitalCheongju 28644South Korea Department of Trauma Surgery Chungbuk National University HospitalCheongju 28644South Korea

BACKGROUND Post-traumatic blunt pericardial injury is a rare condition with only a few reported cases which were generally diagnosed during initial examinations upon ***,pericardial injuries not bad enough to dislocate the heart may only cause intermittent electrocardiogram(ECG)changes or be *** SUMMARY In this case,we report a blunt pericardial injury undetected on preoperative transthoracic echocardiography and chest computed *** misjudged intermittent ECG changes and blood pressure fluctuations as minor symptoms resulting from cardiac contusion and did not provide intensive *** pericardial injury was found incidentally during surgical stabilization of rib fractures and was successfully *** Post-traumatic blunt pericardial ruptures should be considered in patients with blunt chest trauma showing abnormal vital signs and ECG changes.

关键词： Cardiac herniation Flail chest Multiple rib fractures Pericardial rupture Surgical stabilization of rib fractures Case report

Observational Study of Surface Wind along a Sloping Surface over Mountainous Terrain during Winter

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Advances in Atmospheric Sciences 2018年第3期35卷 276-284页

作者： young-hee LEE Gyuwon LEE Sangwon JOO Kwang-Deuk AHN Department of Astronomy and Atmospheric Sciences Kyungpook National University Numerical Data Application Division Numerical Modeling Center

The 2018 Winter Olympic and Paralympic Games will be held in Pyeongchang, Korea, during February and March. We examined the near surface winds and wind gusts along the sloping surface at two outdoor venues in Pyeongchang during February and March using surface wind data. The outdoor venues are located in a complex, mountainous terrain, and hence the near-surface winds form intricate patterns due to the interplay between large-scale and locally forced winds. During February and March, the dominant wind at the ridge level is westerly; however, a significant wind direction change is ob- served along the sloping surface at the venues. The winds on the sloping surface are also influenced by thermal forcing, showing increased upslope flow during daytime. When neutral air flows over the hill, the windward and leeward flows show a significantly different behavior. A higher correlation of the wind speed between upper- and lower-level stations is shown in the windward region compared with the leeward region. The strong synoptic wind, small width of the ridge, and steep leeward ridge slope angle provide favorable conditions for flow separation at the leeward toot of the ridge. The gust factor increases with decreasing surface elevation and is larger during daytime than nighttime. A significantly large gust factor is also observed in the leeward region.

关键词： flow separation gust factor leeward region sloping surface

Detection of stacking orientation error of CFRP composite laminates using ultrasound waves

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中国有色金属学会会刊：英文版 2009年第B9期19卷 124-127页

作者： Sun-Kyu KIM David HSU young-Hwan SEO Kwang-hee IM Division of Mechanical System Engineering Chonbuk National University Center for Nondestructive Evaluation Iowa State University Department of Physical Education Chosun University Department of Automotive Engineering Woosuk University

A jig was developed for generating a shear wave. A pyramid with an isosceles triangle with two 45o was made of aluminum to generate shear waves using two longitudinal transducers based on ultrasonic-polarized mechanism. Also, the signal splitter was connected to the pulser jack on the pulser/receiver and to the longitudinal transducers. Therefore, an experimental way was performed in order to make shear wave on the bottom of aluminum alloyed pyramid. Also, a jig was manufactured and developed for generating a shear wave based on the computer numerical simulation. It is found that the experimentally shear wave variation of newly-designed jig is consistent with computer numerical simulation results and shear wave ultrasonic application can be very useful to detect the defects in CFRP composites.

关键词：碳纤维复合材料误差检测超声波复合材料层板计算机数值模拟堆垛脉冲发生器信号分配器

The Role of Relative Spinal Motion during Feline Galloping for Speed Performance

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Journal of Bionic Engineering 2014年第4期11卷 517-528页

作者： young Kook Kim Jongwon Park Byungho yoon Kyung-Soo Kim Soohyun Kim Robotics Program Korea Advanced Institute of Science and Technology (KAIST) Daejeon 305-701 Republic of Korea Department of Mechanical Engineering Korea Advanced Institute of Science and Technology (KAIST) Daejeon 305-701 Republic of Korea

Felines use their spinal column to increase their running speed at rapid locomotion performance. However, its motion profile behavior during fast gait locomotion has little attention. The goal of this study is to examine the relative spinal motion profile during two different galloping gait speeds. To understand this dynamic behavior trend, a dynamic motion of the feline animal （Felis catus domestica） was measured and analyzed by motion capture devices. Based on the experiments at two different galloping gaits, we observed a significant increase in speed （from 3.2 m.s-1 to 4.33 m.s-1） during the relative motion profile synchronization between the spinal （range： 118.86~ to 168.00~） and pelvic segments （range： 46.35~ to 91.13~） during the hindlimb stance phase （time interval： 0.495 s to 0.600 s）. Based on this discovery, the relative angular speed profile was applied to understand the possibility that the role of the relative motion match during high speed locomotion generates bigger ground reaction force.

关键词： feline galloping galloping gait pattern relative spinal motion speed performance phase match