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Energy & Environmental Materials 2024年第1期7卷 215-221页

作者： Won Seok Cho Dae Myung Hong Wan Jae Dong Tae Hyung lee Chul Jong Yoo donghwa lee Ho Won Jang Jong-Lam lee Department of Materials Science and Engineering Pohang University of Science and Technology(POSTECH)Pohang Gyungbuk 37673Korea Department of Materials Science and Engineering Research Institute of Advanced Materials Seoul National UniversitySeoul 08826Korea

Here we introduce bismuth-based catalysts for the efficient electrochemical reduction of CO_(2)to formic acid(HCOOH),which are composed of petal-shaped Bi_(2)O_(2)CO_(3)(BOC)that spontaneously formed from Bi thin film in aqueous carbonate solution at room *** the electrochemical reduction process,the BOC petals transform to reduced BOC(R-BOC)consisting of individual BOC and Bi *** mismatch between both domains induces biaxial strain at the *** functional theory calculations suggest that the tensile strain on the Bi domain stabilizes the*OCHO intermediate,reducing the thermodynamic barrier toward CO_(2)conversion to *** with the thermodynamic benefit and the unique nanoporous petal-shaped morphology,R-BOC petals have a superior Faradaic efficiency of 95.9%at-0.8 V_(RHE)for the electrochemical conversion of CO_(2)to *** work demonstrates that the spontaneously formed binary phases with desirable lattice strain can increase the activity of bismuth catalysts to the CO_(2)reduction reaction;such a strategy can be applicable in design of various electrocatalysts.

关键词： bismuth carbon dioxide reduction formic acid heterointerfaces strain

Body-centered-cubic martensite and the role on room-temperature tensile properties in Si-added SiVCrMnFeCo high-entropy alloys

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Journal of Materials Science & Technology 2021年第17期76卷 222-230页

作者： Yong Hee Jo Junha Yang Won-Mi Choi Kyung-Yeon Doh donghwa lee Hyoung Seop Kim Byeong-Joo lee Seok Su Sohn Sunghak lee Center for High Entropy Alloys Pohang University of Science and TechnologyPohang 37673South Korea Department of Materials Science and Engineering Division of Advanced Materials SciencePohang University of Science and TechnologyPohang 37673South Korea Graduate Institute of Ferrous Technology Pohang University of Science and TechnologyPohang 37673South Korea Department of Materials Science and Engineering Korea UniversitySeoul 02841South Korea

We present a new class of metastable high-entropy alloys(HEAs),triggering deformation-induced martensitic transformation(DIMT)from face-centered-cubic(FCC)to body-centered-cubic(BCC),i.e.,*** the ab-initio calculation based on 1 st order axial interaction model and combined with the Gibbs free energy calculation,the addition of Si is considered as a critical element which enables to reduce the intrinsic stacking fault energy(ISFE)in Si_xV_((9-x))Cr_(10)Mn_5 Fe_(46)Co_(30)(x=2,4,and 7 at.%)alloy *** ISFE decreases from-30.4 to-35.5 mJ/m^(2)as the Si content increases from 2 to 7 at.%,which well corresponds to the reduced phase stability of FCC against *** BCC-DIMT occurs in all the alloys via intermediate HCP martensite,and the HCP martensite provides nucleation sites of BCC ***,the transformation rate enhances as the Si content increases in an earlier deformation ra ***,the BCC-DIMT is also affected by the phase stability of FCC against BCC,and the stability is the highest at the Si content of 7 at.%.Thus,the 7Si alloy presents the moderate transformation rate in the later deformation *** to the well-controlled transformation rate and consequent strain-ha rdening rate,the 7Si alloy possesses the superior combination of strength and ductility beyond 1 GPa of tensile strength at room *** results suggest that the Si addition can be a favorable candidate in various metastable HEAs for the further property improvement.

关键词： High-entropy alloy(HEA) Deformation-induced martensitic transformation(DIMT) Phase stability Stacking fault energy(SFE)

Aluminum nitride waveguide beam splitters for integrated quantum photonic circuits

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光子学研究:英文版 2023年第7期11卷 1196-1202页

作者： HYEONG-SOON JANG donghwa lee HYUNGJUN HEO YONG-SU KIM HYANG-TAG LIM SEUNG-WOO JEON SUNG MOON SANGIN KIM SANG-WOOK HAN HOJOONG JUNG Center for Quantum Information Korea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea Department of Electrical and Computer Engineering Ajou UniversitySuwon 16499Republic of Korea Division of Nano and Information Technology KIST SchoolKorea University of Science and TechnologySeoul 02792Republic of Korea

We demonstrate integrated photonic circuits for quantum devices using sputtered polycrystalline aluminum nitride(Al N)on ***-chip Al N waveguide directional couplers,which are one of the most important components in quantum photonics,are fabricated and show the output power splitting ratios from 50:50 to 99:*** beam splitters with an extinction ratio of more than 10 d B are also realized from the Al N directional *** the fabricated Al N waveguide beam splitters,we observe Hong–Ou–Mandel interference with a visibility of 91.7%±5.66%.

关键词： waveguide quantum beam

lon migration suppression mechanism via 4-sulfobenzoic acid monopotassium salt for 22.7%stable perovskite solar cells

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Science China Materials 2022年第12期65卷 3368-3381页

作者： Le Bai Fang Yao Rui Wang Baibai Liu Dongmei He Qian Zhou Wenqi Wang Cunyun Xu Xiaobo Hu Shaoqiang Chen Qunliang Song Tingwei Zhou donghwa lee Pengjun Zhao Cong Chen Hua Yang Qianqian Lin Zhigang Zang Jiangzhao Chen Key Laboratory of Optoelectronic Technology&Systems(Ministry of Education) College of Optoelectronic EngineeringChongqing UniversityChongqing 400044China Key Lab of Artificial Micro-and Nano-Structures of Ministry of Education of China School of Physics and TechnologyWuhan UniversityWuhan 430072China Department of Electronic Engineering East China Normal UniversityShanghai 200241China Institute for Clean Energy and Advanced Materials School of Materials and EnergySouthwest UniversityChongqing 400715China School of Physical Science and Technology Southwest UniversityChongqing 400715China Department of Materials Science and Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Korea Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of SciencesUrumqi 830011China School of Material Science and Engineering State Key Laboratory of Reliability and Intelligence of Electrical EquipmentHebei University of TechnologyTianjin 300130China Spallation Neutron Source Science Center Institute of High Energy PhysicsUniversity of Chinese Academy of Sciences(CAS)Dongguan 523803China

The deep-level traps at grain boundaries(GBs)and halide ion migration are quite challenging for further enhancement of the stability and efficiency of perovskite solar cells(PSCs)as well as for the elimination of notorious ***,we report a large-sized strongly coordinated organic anion GB anchoring strategy for suppressing ion migration and passivating defects in planar *** practical implementation of this strategy involves the incorporation of potassium salts containing a large-sized organic counter anion(4-sulfobenzoic acid monopotassium salt,SAMS)into the perovskite *** has been found that anions within SAMS can be firmly anchored at GBs due to the strong coordination interaction between C=O and/or S=O at both ends of bulky anion and undercoordinated Pb^(2+)and/or halide vacancies,along with the hydrogen bond between–OH and *** can not only passivate shallowlevel defects but also cause more effective passivation of the deep-level *** GB manipulation strategy results in a reduced defect density,an increased carrier lifetime as well as suppressed ion migration,which in turn contributed to enhanced efficiency and stability of PSCs together with a thorough elimination of *** a result,the SAMSmodified device with an outstanding fill factor of 0.84 delivers a significant improvement in efficiency(22.7%)in comparison with the control device(20.3%).The unencapsulated modified device demonstrates only little degradation after 1320 h at 60℃.

关键词： perovskite solar cells ion migration suppression defect passivation large-sized organic anions potassium cations

MicroRNAs in pancreatic ductal adenocarcinoma

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World Journal of Gastroenterology 2011年第7期17卷 817-827页

作者： Jong Y Park James Helm Domenico Coppola donghwa Kim Mokenge Malafa Seung Joon Kim Division of Cancer Prevention and Control Moffitt Cancer Center FL 33612 United States Gastrointestinal Tumor Program Moffitt Cancer Center FL 33612 United States Department of Anatomic Pathology Moffitt Cancer Center FL 33612 United States Department of Molecular Oncology MoffittCancer Center FL 33612 United States Department of Internal Medicine Collegeof Medicine the Catholic University of Korea Seoul 137-040South Korea

Ductal adenocarcinoma of the pancreas is a lethal cancer for which the only chance of long-term survival belongs to the patient with localized disease in whom a potentially curative resection can be done. Therefore, biomarkers for early detection and new therapeutic strategies are urgently needed. miRNAs are a recently discovered class of small endogenous non-coding RNAs of about 22 nucleotides that have gained attention for their role in downregulation of mRNA expression at the post-transcriptional level. miRNAs regulate proteins involved in critical cellular processes such as differentiation, proliferation, and apoptosis. Evidence suggests that deregulated miRNA expression is involved in carcinogenesis at many sites, including the pancreas. Aberrant expression of miRNAs may upregulate the expression of oncogenes or downregulate the expression of tumor suppressor genes, as well as play a role in other mechanisms of carcinogenesis. The purpose of this review is to summarize our knowledge of deregulated miRNA expression in pancreatic cancer and discuss the implication for potential translation of this knowledge into clinical practice.

关键词： MicroRNAs Pancreatic cancer

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留学生健康App使用的影响分析

西南科技大学学报（哲学社会科学版） 2023年第4期40卷 87-93页

作者：郑东和上海大学新闻与传播学院上海200072

本文基于计划行为理论(TPB)考察了来华留学生群体使用健康类App对其采取健康行为意愿的影响,以及可能的积极地自我健康管理的作用。本文以在华的韩国、马来西亚学生群体(N=501)为样本,对理论模型拓展的适配度以及各影响因素的中介以及... 详细信息

本文基于计划行为理论(TPB)考察了来华留学生群体使用健康类App对其采取健康行为意愿的影响,以及可能的积极地自我健康管理的作用。本文以在华的韩国、马来西亚学生群体(N=501)为样本,对理论模型拓展的适配度以及各影响因素的中介以及调节作用进行了依次分析。研究结果发现,使用健康App的行为对来华留学生的健康行为态度、健康行为主观规范以及健康知觉行为控制有正向影响。此外,健康行为态度、健康行为主观规范以及健康知觉行为控制在使用健康App和采取健康行为的意愿之间起中介作用。留学生国别对提高使用健康App意愿的行为态度和采取健康行为的主观规范有积极的调节作用。这项研究深入地揭示了来华留学生采取健康行为的前序因素及各因素的影响关系,为未来健康行为方向的研究提供了研究思路。

关键词：来华留学生健康App 健康行为