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Iridium‑Cluster‑Implanted Ruthenium Phosphide Electrocatalyst for Hydrogen Evolution Reaction

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Advanced Fiber Materials 2024年第1期6卷 158-169页

作者： Kyounghoon Jung Dwi Sakti Aldianto Pratama Andi Haryanto Jin Il Jang Hyung Min kim Jae‑Chan kim Chan Woo Lee Dong‑Wan kim School of Civil Environmentaland Architectural EngineeringKorea UniversitySeoul 02841Republic of Korea Department of Chemistry Kookmin UniversitySeoul 02707Republic of Korea Materials Science and Chemical Engineering Center Institute for Advanced EngineeringYongin‑si 17180Republic of Korea

Ruthenium phosphide is a promising catalyst for hydrogen evolution due to its cost-effectiveness compared to *** it faces the challenge of having a high binding energy for hydrogen *** this study,we demonstrate that the incorporation of iridium in ruthenium phosphides lowers the binding energy of hydrogen intermediates,thereby controlling the overpotential and Tafel slope of hydrogen *** the Ir content was doped at 3 at.%,the catalyst achieved an overpotential of 33 mV and a Tafel slope of 33 mV dec^(-1) under acidic conditions,which are similar to those of the benchmark Pt/C *** situ Raman spectroscopy and density functional theory(DFT)calculations suggest that the enhanced catalytic activity originates from the near-neutral Gibbs free energy of hydrogen adsorption on the hollow site of the iridium cluster implanted onto ruthenium phosphide.

关键词： Water electrolysis Ruthenium phosphide Iridium substitution Electronic structure Hydrogen evolution reaction Electrospinning

Animal plant warfare and secondary metabolite evolution

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Natural Products and Bioprospecting 2013年第1期3卷 1-7页

作者： Steffen WÖLL Sun Hee kim Henry Johannes GRETEN Thomas EFFERTH Department of Pharmaceutical Biology Institute of Pharmacy and BiochemistryJohannes Gutenberg-UniversityMainzGermany Institute of Biomedical Sciences(ICBAS) University of PortoPortugal

The enduring discussion,why plants produce secondary metabolites with pharmacologically and toxicologically active towards mammals traces back to the eminent role of medicinal plants in the millennia-old history of *** recent years,the concept of an animal plant warfare emerged,which focused on the co-evolution between plants and *** a reaction to herbivory,plants developed mechanical defenses such as thorns and hard shells,which paved the way for adapted animal *** evolved further defense systems by producing chemicals that exert toxic effects on the animals that ingest *** a result of this selective pressure,animals developed special enzymes,*** P450 monooxigenases(CYP450)that metabolize xenobiotic *** a next step in the evolutionary competition between plants and animals,plants evolved to produce non-toxic pro-drugs,which become toxic only after ingestion by animals through metabolization by enzymes such as *** these sequestered evolutionary developments call to mind an arms race,the term animal plant warfare has been *** evolutionary competition between plants and animals may help to better understand the modes of action of medicinal plants and to foster the efficient and safe use of phytotherapy nowadays.

关键词： natural products phytochemicals liver metabolism cytochrome P450 monooxigenase ABC-transporter herbivore

Sulfonated fluorinated multi-block copolymer hybrid containing sulfonated(poly ether ether ketone) and graphene oxide: A ternary hybrid membrane architecture for electrolyte applications in proton exchange membrane fuel cells

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Journal of Energy Chemistry 2018年第4期27卷 1247-1260页

作者： Ae Rhan kim Mohanraj Vinothkannan Dong Jin Yoo Department of Bioenvironmental Chemistry and R&D Center for CANUTECH Business Incubation Center Chonbuk National University Graduate School Department of Energy Storage/Conversion Engineering Hydrogen and Fuel Cell Research Center Chonbuk National University Department of Life Science Chonbuk National University

A ternary hybrid membrane architecture consisting of sulfonated fluorinated multi-block copolymer （SFMC）, sulfonated （poly ether ether ketone）（SPEEK） and I or 5 wt% graphene oxide （GO） was fabricated through a facile solution casting approach. The simple, but effective monomer sulfonation was performed for SFMC to create compact and rigid hydrophobic backbone structures, while conventional random sulfonation was carried-out for SPEEK. Hydrophilic-hydrophobic-hydrophilic structure of SFMC enhances the compatibility with SPEEK and GO and allows for an unprecedented approach to alter me- chanical strength and proton conductivity of ternary hybrid membrane, as verified from universal test machine （UTM） curves and alternating current （AC） impedance plots. The impact of GO integration on the morphology and roughness of hybrid membrane was scrutinized using field emission scanning electron microscope （FE-SEM） and atomic force microscope （AFM）. Ternary hybrid showed uniform intercalation of GO nanosheets throughout the entire surface of membrane with an increased surface roughness of 8.91 nm. The constructed ternary hybrid membrane revealed excellent water absorption, ion exchange capacity and gas barrier properties, while retaining reasonable dimensional stability. The well-optimized ternary hybrid membrane containing 5 wt% GO revealed a maximum proton conductivity of 111.9 mS/cm, which is higher by a factor of two-fold with respect to that of bare SFMC membrane. The maximum PEMFC power density of 528.07mW/cm2 was yielded by ternary hybrid membrane at a load current density of 1321.1 mA/cm2 when operating the cell at 70 ℃ under 100% relative humidity （RH）. In comparison, a maximum power density of only 182.06 mW/cm2 was exhibited by the bare SFMC membrane at a load current density of 455.56 mA/cm2 under same operating conditions.

关键词： Sulfonated fluorinated multi-block copolymer Sulfonated(poly ether ether ketone) Graphene oxide Hydrogen bonding Proton conductivity

Inversion of two-phase extensional basin systems during subduction of the Paleo-Pacific Plate in the SW Korean Peninsula:Implication for the Mesozoic “Laramide-style” orogeny along East Asian continental margin

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Geoscience Frontiers 2019年第3期10卷 909-925页

作者： Seung-Ik Park Jungrae Noh Hee Jun Cheong Sanghoon Kwon Yungoo Song Sung Won kim M.Santosh Department of Geology Kyungpook National University Department of Earth System Sciences Yonsei University School of Earth Sciences The Ohio State University Geology Division Korea Institute of Geoscience and Mineral Resources School of Earth Sciences and Resources China University of Geosciences Department of Earth Sciences University of Adelaide

During subduction, continental margins experience shortening along with inversion of extensional sedimentary basins. Here we explore a tectonic scenario for the inversion of two-phase extensional basin systems, where the Early-Middle Jurassic intra-arc volcano-sedimentary Oseosan Volcanic Complex was developed on top of the Late Triassic-Early Jurassic post-collisional sequences, namely the Chungnam Basin. The basin shortening was accommodated mostly by contractional faults and related folds. In the basement, regional high-angle reverse faults as well as low-angle thrusts accommodate the overall shortening, and are compatible with those preserved in the cover. This suggests that their spatial and temporal development is strongly dependent on the initial basin geometry and inherited *** in transport direction observed along the basement-sedimentary cover interface is a characteristic structural feature, reflecting sequential kinematic evolution during basin inversion. Propagation of basement faults also enhanced shortening of the overlying sedimentary cover sequences. We constrain timing of the Late Jurassic-Early Cretaceous(ca. 158-110 Ma) inversion from altered K-feldspar 40 Ar/39 Ar ages in stacked thrust sheets and K-Ar illite ages of fault gouges, along with previously reported geochronological data from the area. This "non-magmatic phase" of the Daebo Orogeny is contemporaneous with the timing of magmatic quiescence across the Korean Peninsula. We propose the role of flat/low-angle subduction of the Paleo-Pacific Plate for the development of the "Laramide-style" basement-involved orogenic event along East Asian continental margin.

关键词： Two-phase extensional basin systems Paleo-Pacific Plate Inversion tectonics “Laramide-style” orogeny East Asian continental margin

Portfolio Selection Using Double GAs Searching for Cardinality and Integer Multiplied Optimal Weights

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Economics World 2020年第2期8卷 51-63页

作者： Gumsong Jo Duson kim Namung Ri Hoyong kim kim Il Sung University PyongyangDemocratic People’s Republic of Korea

This paper studied cardinality constrained portfolio with integer *** suggested two optimization models and used two genetic algorithms to solve *** this paper,after finding well matching stocks,according to investor’s target by using first genetic algorithm,we gave optimal integer weight of portfolio with well matching stocks by using second genetic *** numerical comparisons with other feasible portfolios,we verified advantages of designed portfolio with two genetic *** a numerical comparison,we used a prepared data consisted of 18 stocks listed in S&P 500 and numerical example strongly supported the designed portfolio in this ***,we made all comparisons visible through all feasible efficient frontiers.

关键词： portfolio tselection cardinality efficient frontier geneic algorithm(GA) Sharpe ratio

Indolocarbazole-Based Small Molecule Cathode-Active Material Exhibiting Double Redox for High-Voltage Li-Organic Batteries

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Energy & Environmental Materials 2024年第5期7卷 86-94页

作者： Hyunji Park Hyojin Kye Jong-Sung Lee Young-Chang Joo Dong Joo Min Bong-Gi kim Soo Young Park Ji Eon Kwon Laboratory for Supramolecular Optoelectronic Materials(LSOM) Department of Materials Science and EngineeringResearch Institute of Advanced Materials(RIAM)Seoul National University1 Gwanak-roGwanak-guSeoul 08826Korea Functional Composite Materials Research Center Jeonbuk Institute of Advanced Composite MaterialsKorea Institute of Science and Technology(KIST)92 Chudong-roBongdong-eupWanju-gunJeonbuk 55324Korea Department of Organic and Nano System Engineering Konkuk University120 Neungdong-roGwangjin-guSeoul 05029Korea Department of Materials Science and Engineering Seoul National University1 Gwanak-roGwanak-guSeoul 08826Korea Department of JBNU-KIST Industry Academia Convergence Research Jeonbuk National University567 Baekje-daeroDeokjin-guJeonjuJeonbuk 54896Korea

Most organic electrode materials(OEMs)for rechargeable batteries employ n-type redox centers,whose redox potentials are intrinsically limited<3.0 V versus Li^(+)/***,p-type materials possessing high redox potentials experience low specific capacities because they are capable of only a single redox reaction within the stable electrochemical window of typical ***,we report 5,11-diethyl-5,11-dihydroindolo[3,2-b]carbazole(DEICZ)as a novel p-type OEM,exhibiting stable plateaus at high discharge potentials of 3.44 and 4.09 V versus Li^(+)/***,the second redox potential of DEICZ is within the stable electrochemical *** mechanism of the double redox reaction is investigated using both theoretical calculations and experimental measurements,including density functional theory calculations,ex situ electron spin resonance,and X-ray photoelectron ***,hybridization with single-walled carbon nanotubes(SWCNT)improves the cycle stability and rate performance of DEICZ owing to theπ-πinteractions between the SWCNT and co-planar molecular structure of DEICZ,preventing the dissolution of active materials into the *** DEICZ/SWCNT composite electrode maintains 70.4%of its initial specific capacity at 1-C rate and also exhibits high-rate capability,even performing well at 100-C ***,we demonstrate its potential for flexible batteries after applying 1000 bending stresses to the composite electrode.

关键词： composite electrodes flexible batteries indolocarbazoles organic rechargeable batteries p-type

Murine lung eosinophil activation and chemokine production in allergic airway inflammation

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Cellular & Molecular Immunology 2010年第5期7卷 361-374页

作者： C Edward Rose Jr Joanne A Lannigan Paul kim James J Lee Shu Man Fu Sun-sang J Sung Division of Pulmonary and Critical Care Department of MedicineUniversity of Virginia School of MedicineCharlottesvilleVAUSA Department of Microbiology University of Virginia School of MedicineCharlottesvilleVAUSA Center for Immunity Inflammationand Regenerative Medicine and Division of NephrologyDepartment of MedicineUniversity of Virginia School of MedicineCharlottesvilleVAUSA Division of Pulmonary Medicine Department of Biochemistry and Molecular BiologyMayo Clinic ArizonaScottsdaleAZUSA

Eosinophils play important roles in asthma and lung *** models are widely used for assessing the functional significance and mechanistic basis for eosinophil involvements in these ***,little is known about tissue eosinophils in *** addition,little data on eosinophil chemokine production during allergic airway inflammation are *** this study,the properties and functions of homeostatic and activated eosinophils were *** from normal tissues expressed costimulation and adhesion molecules B7-1,B7-2 and ICAM-1 for Ag presentation but little major histocompatibility complex(MHC)class II,and were found to be poor stimulators of T-cell ***,these eosinophils expressed high levels of chemokine mRNA including C10,macrophage inflammatory protein(MIP)-1a,MIP-1c,MIP-2,eotaxin and monocyte chemoattractant protein-5(MCP-5),and produced chemokine *** intracellular chemokines decreased rapidly with concomitant surface marker downregulation upon in vitro culturing consistent with piecemeal *** eosinophils from mice with induced allergic airway inflammation exhibited increased chemokines mRNA expression and chemokines protein production and upregulated MHC class II and CD11c *** were also found to be the predominant producers of the CCR1 ligands CCL6/C10 and CCL9/MIP-1c in inflamed *** production of C10 and MIP-1c correlated with the marked influx of CD11bhigh lung dendritic cells during allergic airway inflammation and the high expression of CCR1 on these dendritic cells(DCs).The study provided baseline information on tissue eosinophils,documented the upregulation of activation markers and chemokine production in activated eosinophils,and indicated that eosinophils were a key chemokine-producing cell type in allergic lung inflammation.

关键词： allergy chemokines eosinophils lung mouse

Antimicrobial and antioxidant properties of medicinal plants used by the Bentian tribe from Indonesia

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Food Science and Human Wellness 2014年第3期3卷 191-196页

作者： Irawan Wijaya Kusuma Murdiyanto Enos Tangke Arung Syafrizal Yong-ung kim Department of Forest Products Faculty of ForestryMulawarman UniversitySamarinda 75118Indonesia Department of Biology Faculty of Mathematic and Natural SciencesMulawarman UniversitySamarinda 75118Indonesia Department of Herbal Pharmaceutical Engineering College of Herbal Bio-industryDaegu Haany UniversityGyeongsangbuk-doSouth Korea

Some selected medicinal plants used by Bentian tribe from Indonesia were evaluated for potential antimicrobial and antioxidant *** leaves stem bark and root of the plants were extracted with n-hexane,ethyl acetate and ethanol to give respective *** activity against Propionibacterium acnes and Candida albicans was determined by an agar well diffusion *** activity was assayed by the DPPH radical scavenging activity *** results showed that n-hexane,ethyl acetate and ethanol extracts of Cananga odorata,ethanolic extract of Chromolaena odorata,and ethanolic extracts of Hyptis capitata and Ampelocissus cinnamomeae displayed good activity against *** at 25–400μg/well of the extracts *** n-hexane and ethanol extracts of Chromolaena odorata and ***,and the n-hexane,ethyl acetate and ethanol extracts of Cananga odorata displayed more activity against *** than others at 25–400μg/well of the extracts *** most antioxidant activities against DPPH were displayed by the ethanol extracts of Ficus variegata stem bark,Leucosyke quadrinerva root and Clausena excavata leaves exhibiting 91%,91%and 86%inhibition,*** present results showed potential of some medicinal plants used by Bentian tribe from Indonesia as natural anti-microbial and anti-oxidant and potentially anti-inflammatory agents.

关键词： Antimicrobial activity Antioxidant activity Natural products Phytochemicals Medicinal plants

Characterization of recycled crumb rubber modified binders containing wax warm additives

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Journal of Traffic and Transportation Engineering(English Edition) 2018年第3期5卷 197-206页

作者： Hyun Hwan kim Mithil Mazumder Soon-Jae Lee Moon-Sup Lee Department of Engineering Technology Texas State University San Marcos TX 78666 USA Materials Science Engineering and Commercialization Program Texas State University San Marcos TX 78666 USA Korea Institute of Civil Engineering and Building Technology Goyang-si Gyeonggi-do 10223 Republic of Korea

This paper addresses the laboratory experiment of performance properties of recycled CRM binders containing artificially aged CRM binders with wax additives. The warm CRM binders were produced using two wax additives （LEADCAP and Sasobit） and then shortterm and long-term aged using the rolling thin film oven （RTFO） and pressure aging vessel （PAV） procedures. The recycled CRM binders were aged through the RTFO and PAV pro- cedures. A set of Superpave binder tests were carried out on the binders through the rotational viscometer, the dynamic shear rheometer （DSR）, and the bending beam rheometer （BBR）. In general, the results of this study indicated that （1） the addition of longterm aged （LTA） CRM binder can significantly increase the viscosity of the recycled CRM binders as expected, （2） the wax additives in recycled CRM binders were still effective to improve the viscosity and rutting properties even after experiencing the aging process, （3） the CRM binders containing wax additives showed the higher rutting resistance compared to the control CRM binders, （4） the recycled CRM binder containing wax additives was found to have less resistance to fatigue and low temperature cracking, （5） wax warm additives into the recycled CRM binders seemed to have a significant role for cracking properties, based upon their substantial amount.

关键词： CRM binder Wax additives Rotational viscosity Recycling Rutting