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Journal of Environmental Sciences 2017年第12期29卷 84-91页

作者： In-Young Chung Yu-Mi Park Hyun-Jeoung Lee Hyuk Kim Dong-Hoon Kim Il-Gyu Kim Sang-Min Kim Young-Sun Do kwang-seol seok Jung-Hwan Kwon Chemical Research Division Environmental Health Research Department National Institute of Environmental ResearchIncheon Division of Environmental Science and Ecological Engineering Korea University

It is thought that there are many unregulated anthropogenic chemicals in the *** risk assessment of chemicals, it is essential to estimate the predicted environmental concentrations. As an effort of identifying residual organic contaminants in air and water in Korea, nontarget screening using two-dimensional gas chromatography time-of-flight mass spectrometry（GC × GC-TOFMS） was conducted at 10 sites using polyurethane foam passive air sampler and at 6 sites using polydimethyl siloxane（PDMS） passive water sampler in three different seasons in 2014. More than 600 chemical peaks were identified satisfying the identification criteria in air and water samples, respectively, providing a list for further investigation. Chemical substances with reported national emission rates in2014（n = 149） were also screened for potential existence in the environment using a level Ⅱ fugacity model. Most of chemical substances classified as not detectable were not identified with detection frequency greater than 20% by nontarget screening, indicating that a simple equilibrium model has a strong potential to be used to exclude chemicals that are not likely to remain in the environment after emissions from targeted monitoring.

关键词： Nontarget screening GC × GC-TOFMS Passive sampling Pollutant release and transfer register(PRTR) Fugacity model

Surface engineering of ZnO electrocatalyst by N doping towards electrochemical CO_(2) reduction

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Journal of Energy Chemistry 2024年第1期88卷 71-81,I0002页

作者： Rohini Subhash Kanase Getasew Mulualem Zewdie Maheswari Arunachalam Jyoti Badiger Suzan Abdelfattah Sayed kwang-Soon Ahn Jun-seok Ha Uk Sim Hyeyoung Shin Soon Hyung Kang Department of Interdisciplinary Program for Photonic Engineering Chonnam National UniversityGwangju 61186Republic of Korea Graduate School of Energy Science and Technology(GEST) Chungnam National University99 Daehak-roYuseong-guDaejeon 34134Republic of Korea Department of Chemistry Education and Optoelectronic Convergence Research Center Chonnam National UniversityGwangju 61186Republic of Korea Department of Advanced Chemicals and Engineering Chonnam National UniversityGwangju 61186Republic of Korea School of Chemical Engineering Yeungnam UniversityGyeongsan 38541Republic of Korea Department of Energy Engineering Korea Institute of Energy Technology(KENTECH)Naju 58217Republic of Korea

The discovery of efficient,selective,and stable electrocatalysts can be a key point to produce the largescale chemical fuels via electrochemical CO_(2) reduction(ECR).In this study,an earth-abundant and nontoxic ZnO-based electrocatalyst was developed for use in gas-diffusion electrodes(GDE),and the effect of nitrogen(N)doping on the ECR activity of ZnO electrocatalysts was ***,a ZnO nanosheet was prepared via the hydrothermal method,and nitridation was performed at different times to control the N-doping *** an increase in the N-doping content,the morphological properties of the nanosheet changed significantly,namely,the 2D nanosheets transformed into irregularly shaped ***,the ECR performance of Zn O electrocatalysts with different N-doping content was assessed in 1.0 M KHCO_(3) electrolyte using a gas-diffusion electrode-based ECR *** the ECR activity increased after a small amount of N doping,it decreased for higher N doping *** them,the N:ZnO-1 h electrocatalysts showed the best CO selectivity,with a faradaic efficiency(FE_(CO))of 92.7%at-0.73 V *** hydrogen electrode(RHE),which was greater than that of an undoped Zn O electrocatalyst(FE_(CO)of 63.4%at-0.78 V_(RHE)).Also,the N:ZnO-1 h electrocatalyst exhibited outstanding durability for 16 h,with a partial current density of-92.1 mA cm^(-2).This improvement of N:ZnO-1 h electrocatalyst can be explained by density functional theory calculations,demonstrating that this improvement of N:ZnO-1 h electrocatalyst comes from(ⅰ)the optimized active sites lowering the free energy barrier for the rate-determining step(RDS),and(ⅱ)the modification of electronic structure enhancing the electron transfer rate by N doping.

关键词： ZnO N-doped ZnO Gas-diffusion electrode CO Selectivity Electrochemical CO_(2)reduction

Optimizing multi-parameter distributed fiber sensors:a hybrid Rayleigh-Brillouin-Raman System approach

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Light(Science & Applications) 2024年第3期13卷 393-395页

作者： kwang Yong Song Dept.of Physics Chung-Ang University84 Heukseok-roDongjak-guSeoul 06974Korea

An optimized single-end hybrid Rayleigh,Brillouin,and Raman distributed fiber sensing system has been developed for simultaneous measurement of multiple *** system integrates 3-bit pulse coding for the Raman signal and the Brillouin amplification of the Rayleigh-backscattered signal,discriminating strain,temperature,and vibration using a single sensing fiber.

关键词： fiber Rayleigh signal

Pyrometallurgical recycling of end-of-life lithium-ion batteries

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1554-1571页

作者： Juheon Lee kwang Won Park Il Sohn Sanghoon Lee Department of Materials Science and Engineering Seoul 03722Korea Yonsei Industry Cooperation Center Yonsei UniversitySeoul 03722Korea RD Solution Wanju gunJeollabuk do 55365Korea

The global importance of lithium-ion batteries(LIBs)has been increasingly underscored with the advancement of high-performance energy storage ***,the end-of-life of these batteries poses significant challenges from environmental,economic,and resource management *** review paper focuses on the pyrometallurgy-based recycling process of lithium-ion batteries,exploring the fundamental understanding of this process and the importance of its *** on the high energy consumption and emission gas issues of the pyrometallurgical recycling process,we systematically analyzed the capital-intensive nature of this process and the resulting technological ***,we conducted an in-depth discussion on the future research directions to overcome the existing technological barriers and *** review will provide valuable insights for researchers and industry stakeholders in the battery recycling field.

关键词： spent lithium-ion batteries recycling sustainability lithium valuable metal

Stable, efficient inverted perovskite solar cells enabled by the multifunctional ytterbium oxide buffer

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Science China Chemistry 2024年第8期67卷 2423-2424页

作者： Manman Hu Sang Il seok Department of Energy and Chemical Engineering Ulsan National Institute of Science and TechnologyUlsan 44919Republic of Korea

Significant advancements in single-junction inverted perovskite solar cells (PSCs) have led to power conversion efficiencies (PCEs) exceeding 25% [1]. However, their operational stability under strict conditions falls short compared with commercial solar panels, primarily due to the ion migration. This migration alters the chemical composition within the perovskite layer, increasing the heterogeneity and forming degradation sites [2]. Additionally, ion accumulation at metal interfaces corrodes electrodes, while metal diffusion into perovskite layers further compromises the stability, highlighting critical areas for the improvement in long-term device performance [3,4].

关键词： perovskite exceeding stability

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Research on Cavitation Characteristics and Influencing Factors of Herringbone Gear Pump

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2917-2946页

作者： Jinlong Yang kwang-Hee Lee Chul-Hee Lee Department of Mechanical Engineering of Inha University Incheon22212South Korea

Cavitation is a common issue in pumps,causing a decrease in pump head,a fall in volumetric efficiency,and an intensification of outlet flow *** is one of the main hazards that affect the regular operation of the *** on pump cavitation mainly focuses on mixed flow pumps,jet pumps,external spur gear pumps,***,there are few cavitation studies on external herringbone gear *** addition,pumps with different working principles significantly differ in the flow and complexity of the internal flow ***,it is urgent to study the cavitation characteristics of external herringbone gear *** with experimentalmethods,visual research and cavitation area identification are achieved through computation fluid dynamic(CFD),and changing the boundary conditions and shape of the gear rotor is *** simulation yields a head error of only 0.003%under different grid numbers,and the deviation between experimental and simulation results is less than 5%.The study revealed that cavitation causes flow pulsation at the outlet,and the cavitation serious area is mainly distributed in the meshing gap and meshing *** can be inhibited by reducing the speed,increasing the inlet pressure,and changing the helix angle can be *** example,when the inlet pressure is 5 bar,the maximumgas volume fraction in themeshing area is less than 50%.These results provide a reference for optimizing the design and finding the optimal design parameters to reduce or eliminate cavitation.

关键词： Herringbone gear pump cavitation rotating speed inlet pressure helix angle TwinMesh

Changes in microorganisms and metabolites during long-term fermentation of commercially manufactured anchovy sauce

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Food Science and Human Wellness 2024年

作者： Daehyeon Kim Seong-Eun Park Eun-Ju Kim Seung-Ho Seo kwang-Moon Cho Sun Jae Kwon Hong-seok Son Department of Biotechnology College of Life Sciences and Biotechnology Korea University Sonlab Inc. 3. AccuGene Inc.

This study was performed to investigate the changes in microbial communities and metabolites during the long-term fermentation of commercially manufactured anchovy sauce. Samples of commercial anchovy sauce were collected from large-scale fermentation tanks with fermentation periods of up to 7.87 years. The complex bacterial community was simplified to two genera， Tetragenococcus and Halanaerobium， after approximately 0.55 years of fermentation. Although genera， such as Saccharomyces， Cladosporium， Candida， and Aspergillus， were relatively dominant， no clear pattern was identified in fungal community analysis. The longitudinal metabolite profile demonstrated that approximately half (55.8%) of the metabolites present in anchovy sauce were produced within a year of fermentation due to rapid fermentation. Despite the static microbial community， the contents of several metabolites including amino acids and biogenic amines changed continuously during the long-term fermentation of anchovy sauce. This study provides novel insights into the changes in microbiota and metabolites in fish sauce produced without any starter inoculation.

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A novel method for determining the resistivity of compressed superconducting materials

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Matter and Radiation at Extremes 2024年第4期9卷 1-3页

作者： Liling Sun Qi Wu Shu Cai Yang Ding Ho-kwang Mao Center for High Pressure Science and Technology Advanced Research Beijing 100094China Institute of Physics Chinese Academy of SciencesBeijing 100190China

The measurement of resistivity in a compressed material within a diamond anvil cell presents significant *** high-pressure exper-imental setup makes it difficult to directly measure the size changes induced by pressure in the three crystallographic directions of the *** this study,we introduce a novel and effective method that addresses these technical *** method is anticipated to offer a valuable foundation for high-pressure investigations on quantum materials,particularly those with anisotropic layered structures.

关键词： resistivity method foundation

Omnidirectional color wavelength tuning of stretchable chiral liquid crystal elastomers

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Light(Science & Applications) 2024年第6期13卷 1062-1074页

作者： Seungmin Nam Wontae Jung Jun Hyuk Shin Su seok Choi Department of Electrical Engineering Pohang University of Science and Technology(POSTECH)PohangKorea

Wavelength-tunable structural colors using stimuli-responsive materials,such as chiral liquid crystals(CLCs),have attracted increasing attention owing to their high functionality in various tunable photonic ***,on-demand omnidirectional wavelength control is highly desirable from the perspective of wavelength-tuning ***,despite numerous previous research efforts on tunable CLC structural colors,only mono-directional wavelength tuning toward shorter wavelengths has been employed in most studies to *** this study,we report the ideally desired omnidirectional wavelength control toward longer and shorter wavelengths with significantly improved tunability over a broadband wavelength *** using areal expanding and contractive strain control of dielectric elastomer actuators(DEAs)with chiral liquid crystal elastomers(CLCEs),simultaneous and omnidirectional structural color-tuning control was *** breakthrough in omnidirectional wavelength control enhances the achievable tuning freedom and versatility,making it applicable to a broad range of high-functional photonic applications.

关键词： tuning tunable directional

Surface-functionalized hole-selective monolayer for high efficiency single-junction wide-bandgap and monolithic tandem perovskite solar cells

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Journal of Energy Chemistry 2024年第1期88卷 317-326,I0008页

作者： Devthade Vidyasagar Yeonghun Yun Jae Yu Cho Hyemin Lee Kyung Won Kim Yong Tae Kim Sung Woong Yang Jina Jung Won Chang Choi Seonu Kim Rajendra Kumar Gunasekaran seok Beom Kang kwang Heo Dong Hoe Kim Jaeyeong Heo Sangwook Lee School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Department of Materials Science and Engineering and Optoelectronics Convergence Research CenterChonnam National UniversityGwangju 61186Republic of Korea Department of Materials Science and Engineering Korea UniversitySeoul 02841Republic of Korea Department of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul 05006Republic of Korea

Carbazole moiety-based 2PACz([2-(9H-carbazol-9-yl)ethyl]phosphonic acid)self-assembled monolayers(SAMs)are excellent hole-selective contact(HSC)materials with abilities to excel the charge-transferdynamics of perovskite solar cells(PSCs).Herein,we report a facile but powerful method to functionalize the surface of 2PACz-SAM,by which reproducible,highly stable,high-efficiency wide-bandgap PSCs can be *** 2PACz surface treatment with various donor number solvents improves assembly of 2PACz-SAM and leave residual surface-bound solvent molecules on 2PACz-SAM,which increases perovskite grain size,retards halide segregation,and accelerates hole *** surface functionalization achieves a high power conversion efficiency(PCE)of 17.62%for a single-junction wide-bandgap(~1.77 e V)*** also demonstrate a monolithic all-perovskite tandem solar cell using surfaceengineered HSC,showing high PCE of 24.66%with large open-circuit voltage of 2.008 V and high fillfactor of 81.45%.Our results suggest this simple approach can further improve the tandem device,when coupled with a high-performance narrow-bandgap sub-cell.

关键词： Perovskite solar cells 2PACz Monolithic tandem solar cells Wide bandgap