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Journal of Energy Chemistry 2022年第4期31卷 549-554页

作者： Dong-Ho Kang yong-Jun Park Yun-Sung Jeon nam-Gyu Park School of Chemical Engineering and Center for Antibonding Regulated Crystals Sungkyunkwan UniversitySuwon 16419Korea

Perovskite solar cells (PSCs) employing formamidinium lead iodide (FAPbI_(3)) have shown high ***,operational stability has been issued due to phase instability of α phase FAPbI_(3) at ambient *** precursors in the perovskite precursor solution has been proposed to improve not only power conversion efficiency (PCE) but also device ***,there is a controversial issue on the beneficial effect on PCE and/or stability between excess FAI and excess PbI_(2).We report here extended X-ray absorption fine structure (EXAFS) of FAPbI_(3) to study local structural change and explain the effect of excess precursors on photovoltaic performance and *** films prepared from the precursor solution with excess PbI_(2)shows better stability than those from the one with excess FAI,despite similar PCE.A rapid phase transition from α phase to non-perovskite δ phase is observed from the perovskite film formed by excess ***,the (Pb-I) bond distance evaluated by the Pb L_(III)-edge EXAFS study is increased by excess FAI,which is responsible for the phase transition and poor device *** work can provide important insight into local structure-stability relation in the FAPbI_(3)-based PSCs.

关键词： Extended X-ray absorption fine structure EXAFS Excess precursor Local structure Stability Perovskite solar cells

Habitat Use, Home Range, and Hibernaculum of the Mongolian Racerunner, Eremias argus (Lacertidae, Reptilia) in a Coastal Sand Dune in South Korea

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Asian Herpetological Research 2012年第2期3卷 133-140页

作者： Il-Hun KIM nam-yong RA Daesik PARK Department of Biology Kangwon National University Division of Science Education Kangwon National University

Information on habitat use is critical in sizing protected areas for endangered reptile species. To investigate habitat use, home range, and hibernaculum of the endangered Mongolian Racerunner(Eremias argus), we radio-tracked 40 specimens in a coastal sand dune in South Korea. Of the 163 locations recorded during the breeding season, 150(92.0%) were in grass sand dunes, and the rest(8.0%), all associated with the same lizard, were in shrub sand dunes. All of the 123 locations recorded during the non-breeding season were in grass sand dunes. No lizards were found in the grasslands abutting the dunes. The four lizards with identifiable hibernation sites were found under an average of 17.8 cm of sand and were all located in grass sand dunes. The lizards moved approximately 5 m daily and used 162 m2of home range(computed by minimum convex polygon, MCP) during the breeding season, and they moved approximately 2 m and used 68 m2of home range during the non-breeding season. However, the mean daily moved distances and MCP home ranges were not statistically significantly different between the seasons or between males and females. Our results suggest that in coastal sand dunes, E. argus uses grass sand dunes as its main habitat throughout the year. This finding could be used to determine the appropriate habitat size and to designate for the conservation of this endangered species.

关键词： coastal sand dune spatial ecology Eremias argus lizard radio-telemetry

Sexual dimorphism and sex-differential migration of Little Buntings(Emberiza pusilla)at an East Asian stopover site

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Avian Research 2022年第1期13卷 87-93页

作者： Sook-Young Cho Hyun-Young nam Se-Young Park Chang-yong Choi Bird Research Center Korea National Park Research InstituteJeonnam58863Republic of Korea Division of Zoology Honam National Institute of Biological ResourcesMokpo58762Republic of Korea School of Biological Sciences College of Natural SciencesSeoul National UniversitySeoul08826Republic of Korea Department of Agriculture Forestry and BioresourcesCollege of Agriculture and Life SciencesSeoul National UniversitySeoul08826Republic of Korea

Sex differences in morphology provide key information for understanding a species'morphological adaptations in relation to the evolution of sexual *** migratory birds,morphological traits have adapted to long-distance travel,and sexual dimorphism is typically related to sex-differential migration *** Buntings(Emberiza pusilla)have one of the longest migrations and are the least dichromatic species among the Emberiza *** this study,we measured sexual size dimorphism and sexual dichromatism of Little Buntings in relation to the spring arrival dates at a stopover site in *** length was the most important predictor for identifying sex;the wings of males were longer than those of *** also had a significantly stronger chestnut color of the head feathers than females,but this color difference was more prominent in the spring than in the *** arrived earlier than females by four *** dates correlated with both size and color,but unlike other bunting species previously studied in the same area,there was no clear sex-differential trend in the relationship between arrival date and morphological *** differences in the degree of sexual dichromatism suggest that chestnut plumage coloration can be used as a social or sexual signal of males in the breeding *** correlation of size and color to early arrival regardless of sex may indicate that a preference for assortative mating exists or that a sex-differential migration strategy is not clearly defined in the early stages of northward *** findings on the sexual dimorphism of Little Buntings provide insight into the evolution of the sex-differential migration of buntings in the East Asian Flyway.

关键词： Digital photography Emberiza pusilla Little Bunting Protandrous migration Sexual dichromatism Sexual dimorphism

On extensions of matrix rings with skew Hochschild 2-cocycles

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Frontiers of Mathematics in China 2016年第4期11卷 869-900页

作者： Chan yong HONG nam Kyun KIM Tai Keun KWAK Yang LEE Department of Mathematics and Research Institute for Basic Sciences Kyung Hee University Seoul 02447 Korea School of Basic Sciences Hanbat National University Daejeon 34158 Korea Department of Mathematics Daejin University Pocheon 11159 Korea Department of Mathematics Pusan National University Pusan 46241 Korea

We study structures of endomorphisms and introduce a skew Hochschild 2-cocycles related to Hochschild 2-cocycle. We moreover define skew Hochschild extensions equipped with skew Hochschild 2-cocycles, and then we examine uniquely clean, Abelian, directly finite, symmetric, and reversible ring properties of skew Hochschild extensions and related ring systems. The results obtained here provide various kinds of examples of such rings. Especially, we give an answer negatively to the question of H. Lin and C. Xi for the corresponding Hochschild extensions of reversible （or semicommutative） rings. Finally, we establish three kinds of Hochschild extensions with Hochschild 2-cocycles and skew Hochschild 2-cocycles.

关键词： Skew Hochschild extensions matrix rings skew triangular matrix rings (uniquely) clean rings symmetric rings

Effect of nanoclay on properties of porous PVdF membranes

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 141-147页

作者： Hae-Young HWANG Deuk-Ju KIM Hyung-Jun KIM Young-Taik HONG Sang-yong nam School of Materials Science and Engineering Engineering Research Institute i-Cube Center Gyeongsang National University Fuel Cell Research Center Korea Institute of Science and Technology Seoul 136-791 Korea Energy Material Research Center Korea Research Institute of Chemical Technology Daejeon 305-600 Korea

The main requirements for battery separators are high porosity which can serve pathways of lithium ion and space for gel electrolytes to impregnate in a membrane and mechanical strength to allow easy handling for battery assembly. Generally, it appears the trade-off relationship between the porosity and mechanical strength of the membrane. PVdF composite membranes containing nano-size clays were used to improve the mechanical strength of the membrane without affecting the membrane porosity. The composite membranes were prepared by phase inversion method controlling the membrane preparation conditions such as retention time. The resultant membranes show increased mechanical properties with similar membrane porosity around 80 % compared to the pristine PVdF membrane. Incorporation of nonoclay can be considered as an effective method to improve the mechanica! strength in porous membrane supports, especially in a separator.

关键词： Li-ion battery separator poly(vinylidene fluoride) nanocomposite

Regeneration of waste SCR catalyst by air lift loop reactor

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Journal of Central South University 2013年第5期20卷 1314-1318页

作者： LEE Jung-bin EOM yong-seok KIM Jun-han CHUN Sung-nam Technology Commercialization Office Korea Electric Power Research Institute

A solution of 0.1 mol/L to 1.0 mol/L H2SO4 can dissolve alkali metals and alkaline earth metals which weaken an active site of SCR catalyst. The waste catalyst washed with 0.5 mol/L H2SO4 regained the best catalytic activity. When a concentration of the sulfuric acid is less than 0.5 mol/L, sufficient cleaning effects cannot be obtained. In contrast, when the concentration is greater than 1.0 tool/L, the active components, vanadium and tungsten are undesirably eluted. The total BET surface of the catalyst regenerated by air lift loop reactor showed almost the same as that of fresh catalyst due to the removal of insoluble compounds which may be penetrated into pores of catalyst. The addition of a solution of 0.075 mol/L ammonium vanadate （NHnVO3） and 0.075 mol/L ammonium paratungstate （5（NH4）20· 12WO3-5H20） to 0.1 mol/L H2SO4 significantly increases the activity of the waste catalyst.

关键词： nitrogen oxide regeneration selective catalyst reduction air lift loop reactor catalyst

Impact of adolescent complex regional pain syndrome on the psychopathology of young men ahead of military service: A retrospective cohort analysis of Korean conscription data

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Military Medical Research 2021年第3期8卷 363-372页

作者： Shin-Heon Lee Myeong-Jin Ko Taek-Kyun nam Jeong-Taik Kwon yong-Sook Park Department of Neurosurgery College of MedicineChung-Ang UniversitySeoul 06973South Korea

Background: The relationship between physical and psychopathological features in complex regional pain syndrome(CRPS) has been a subject of constant interest, but no data are available in adolescents. Therefore, we aimed to identify the factors associated with psychopathology in adolescents with CRPS ahead of military ***: We retrospectively reviewed all conscription examinees who had completed a Military Personality Inventory(MPI) during a period between February 2013 and December 2016. A total of 63 persons with a history of CRPS(19-years of age for all) were enrolled. Basic demographic and pain-related data were analyzed to examine their association with MPI results. The mean FGR score as well as the 8 subdomain scores were compared between those with pain duration at <15 months(n=30) vs. ≥15 months(n=33). Binary MPI results(normal-abnormal) were also compared between the two ***: In multivariate analysis, abnormal MPI was associated with pain duration, with an odds ratio(OR) at 1.05 for every 1-month increase [95% confidence interval(CI) 1.02–1.08;P=0.002]. Subjects with pain duration at ≥15 months have lower faking good response score(P<0.001 vs. those with pain duration at <15 months), and higher abnormal MPI result rate, faking bad response, inconsistency, anxiety, depression, somatization, paranoid, personality disorder cluster A, and personality disorder cluster B scores(P<0.05). Pain duration was significantly associated with the MPI ***: Pain duration is associated with psychopathology in adolescents with CRPS. Psychopathologic features increased as the disease duration increased. A comprehensive understanding of time-dependent psychopathological factors could support the planning of multimodal approaches for managing adolescent CRPS.

关键词： Chronic pain Complex regional pain syndromes Psychopathology Personality inventory Adolescent Military personnel

Duo Property on the Monoid of Regular Elements

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Algebra Colloquium 2022年第2期29卷 203-216页

作者： Chan yong Hong Hong Kee Kim nam Kyun Kim Tai Keun Kwak Yang Lee Department of Mathematics Kyung Hee UniversitySeoul 02447Korea Department of Mathematics and RINS Gyeongsang National University Jinju 52828Korea School of Basic Sciences Hanbat National UniversityDaejeon 34158Korea Department of Mathematics Daejin UniversityPocheon 11159Korea Department of Mathematics Yanbian UniversityYanjiJilin 133002China Instituteof Basic Science Daejin UniversityPocheon 11159Korea

We study the right duo property on regular elements,and we say that rings with this property are right *** is first shown that the right duo property is preserved by right quotient rings when the given rings are right *** prove that thepolynomial ring over a ring R is right DR if and only if R is *** is also proved that for a prime number p,the group ring KG of a finite p-group G over a field K of characteristic p is right DR if and only if it is right duo,and that there exists a group ring KG that is neither DR nor duo when G is not a p-group.

关键词： right DR ring right duo ring quotient ring (skew)polynomial ring group ring

Wave prediction in a port using a fully nonlinear Boussinesq wave model

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Acta Oceanologica Sinica 2019年第7期38卷 36-47页

作者： Young-Kwang Choi Seung-nam Seo Jin-yong Choi Fengyan Shi Kwang-Soon Park Civil and Architectural Engineering Department KEPCO Engineering and ConstructionGimcheon-si 39660Republic of Korea Task Force for Construction of RV ISABU Support Facility Korea Institute of Ocean Science and TechnologyBusan Metropolitan City 49111Republic of Korea Operational Oceanography Research Center Korea Institute of Ocean Science and TechnologyBusan Metropolitan City 49111Republic of Korea Center for Applied Coastal Research University of DelawareNewark DE 19716USA

A wave forecasting system using FUNWAVE-TVD which is based on the fully nonlinear Boussinesq equations by Chen(2006)was developed to provide an accurate wave prediction in the Port of Busan,South *** system is linked to the Korea Operational Oceanographic System(KOOS)developed by Park et al.(2015).The computational domain covers a region of 9.6 km×7.0 km with a grid size of 2 m in both directions,which is sufficient to resolve short waves and dominant sea *** total number of grid points exceeds 16 millions,making the model computational *** provide real-time forecasting,an interpolation method,which is based on pre-calculated results of FUNWAVE-TVD and SWAN forecasting results at the FUNWAVE-TVD offshore boundary,was used.A total of 45 cases were pre-calculated,which took 71 days on 924 computational cores of a Linux cluster *** wave generation and propagation from the deep water were computed using the SWAN in *** results provided a boundary condition for the FUNWAVE-TVD forecasting *** verify the model,wave observations were conducted at three locations inside the port in a time period of more than 7 months.A model/model comparison between FUNWAVE-TVD and SWAN was also carried *** is found that,FUNWAVE-TVD improves the forecasting results significantly compared to SWAN which underestimates wave heights in sheltered areas due to incorrect physical mechanism of wave diffraction,as well as large wave heights caused by wave reflections inside the port.

关键词： real-time wave forecasting FUNWAVE-TVD SWAN KOOS wave observations wave diffraction

Theoretical investigation on the elusive biomimetic iron(Ⅲ)-iodosylarene chemistry: An unusual hydride transfer triggers the Ritter reaction

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Chinese Chemical Letters 2021年第12期32卷 3857-3861页

作者： Lanping Gao Xiaolu Chen Dongru Sun Hua Zhao Yufen Zhao Wonwoo nam yong Wang Institute of Drug Discovery Technology Ningbo UniversityNingbo 315211China Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences Ningbo UniversityNingbo 3152UChina Department of Chemistry and Nano Science Ewha Womans UniversitySeoul 03760Korea

Introduction of iodosylarnes into biomimetic nonheme chemistry has made great achievement on identification of the subtle metal-oxygen reaction intermediates. However, after more than three decades of experimental and theoretical efforts the nature of the metal-iodosylarene adducts and the related dichotomous one-oxidant/multiple-oxident controversy have remained a matter of speculation. Herein, we report a theoretical study of the structure-activity relationship of the noted iron(Ⅲ)-iodsylarene complex,FeⅢ(Ph IO)(OTf)3(1), in oxygenation of cyclohexene. The calculated results revealed that 1 behaves like a chameleon by adapting its roles as a 2 e-oxidant or an oxygen donor, as a response to the regioselective attack of the C–H bond and the C=C bond. The oxidative C–H bond activation by 1 was found, for the first time, to proceed via a novel hydride transfer process to form a cyclohexene carbonium intermediate,such non-rebound step triggers the Ritter reaction to uptake an acetonitrile molecule to form the amide product, or proceeds with the rebound of the hydroxyl group return to the solvent cage to form the hydroxylated product. While in the C=C bond activation, 1 is a normal oxygen donor and shows two-state reactivity to present the epoxide product via a direct oxygen atom transfer mechanism. These mechanistic findings fit and explain the famous Valentine’s experiments and enrich the non-rebound scenario in bioinorganic chemistry.

关键词： Reaction mechanism DFT calculations Metal-iodosylbenzene Ritter reaction Olefin oxidation