检索结果-南通市图书馆

Scalable Ir‑Doped NiFe_(2)O_(4)/TiO_(2)heterojunction Anode for Decentralized Saline Wastewater Treatment and h_(2)Production

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第3期17卷 1-18页

作者： Sukhwa hong Jiseon kim Jaebeom Park Sunmi Im Michael R.hoffmann Kangwoo Cho Division of Environmental Science and Engineering Pohang University of Science and Technology(POSTECH)Pohang 790−784Korea Linde Laboratory California Institute of TechnologyPasadenaCA 91125USA Institute for Convergence Research and Education in Advanced Technology(I‑CREATE) Yonsei University International CampusIncheon 21983Republic of Korea

Wastewater electrolysis cells(WECs)for decentralized wastewater treatment/reuse coupled with h_(2)production can reduce the carbon footprint associated with transportation of water,waste,and energy *** study reports Ir-doped NiFe_(2)O_(4)(NFI,~5 at%Ir)spinel layer with TiO_(2)overlayer(NFI/TiO_(2)),as a scalable heterojunction anode for direct electrolysis of wastewater with circumneutral ph in a single-compartment *** dilute(0.1 M)NaCl solutions,the NFI/TiO_(2)marks superior activity and selectivity for chlorine evolution reaction,outperforming the benchmark IrO_(2).Robust operation in near-neutral ph was *** including operando X-ray absorption spectroscopy unveiled crucial roles of TiO_(2) which serves both as the primary site for Cl−chemisorption and a protective layer for NFI as an ohmic *** electrolysis of Nh4+-laden synthetic wastewater demonstrated that NFI/TiO_(2)not only achieves quasi-stoichiometric Nh_(4)^(+)-to-N_(2)conversion,but also enhances h_(2)generation efficiency with minimal competing reactions such as reduction of dissolved oxygen and reactive *** scaled-up WEC with NFI/TiO_(2)was demonstrated for electrolysis of toilet wastewater.

关键词： Wastewater electrolysis cell Ir-doped NiFe_(2)O_(4) Reactive chlorine species Decentralized h_(2)production On-site wastewater treatment

Prominent cycling reversibility and kinetics enabled by CaTiO3 protective layer on Zn metal for aqueous Zn-ion batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 245-258页

作者： Gaeun Lee Yong Nam Ahn Seongjoon So Chanwoo Park Jong-Seong Bae Taehyun Park Il Tae kim Jaehyun hur School of Chemical Biological and Battery Engineering Gachon University Seongnam Busan Center Korea Basic Science Institute

Aqueous Zn-ion batteries （AZIBs） have received considerable attention owing to their various advantages such as safety,low cost,simple battery assembly conditions,and high ionic ***,they still suffer from serious problems,including uncontrollable dendrite growth,corrosion,hydrogen evolution reaction （hER） from water decomposition,electrode passivation,and unexpected *** creation of a uniform artificial nanocrystal layer on the Zn anode surface is a promising strategy for resolving these ***,we propose the use of a perovskite CaTiO3（CTO） protective layer on Zn（CTO@Zn） as a promising approach for improving the performance of *** CTO artificial layer provides an efficient pathway for Zn ion diffusion towards the Zn metal because of the high dielectric constant （εr=180） and ferroelectric characteristics that enable the alignment of dipole moments and redistribute the Zn2+ions in the CTO *** avoiding the direct contact of the Zn anode with the electrolyte solution,the uneven dendrite growth,corrosion,parasitic side reactions,and hER are mitigated,while CTO retains its mechanical and chemical robustness during ***,CTO@Zn demonstrates an improved lifespan in a symmetric cell configuration compared with bare ***@Zn shows steady overpotential （～68 m V） for 1500 h at 1 mA cm-2/0.5 mA h cm-2,excelling bare ***,when paired with the V2O5-C cathode,the CTO@Zn//V2O5-C full battery delivers 148.4 mA h g-1（based on the mass of the cathode） after 300 *** study provides new insights into Zn metal anodes and the development of high-performance AZIBs.

关键词： Perovskite

Electron-Cyclotron Laser Using Free-Electron Two-Quantum Stark Radiation in a Strong Uniform Axial Magnetic Field and an Alternating Axial Electric Field in a Voltage-Supplied Pill-Box Cavity

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2016年第3期33卷 56-59页

作者： S.h.kim Church Road 9236 Dallas Texas 75231 USA

We consider the radiation from the beam electrons traveling in a strong uniform axial magnetic field and an axial alternating electric field of wavelength Aw generated by a voltage-supplied pill-box cavity. The beam electrons emit genuine laser radiation that propagates only in the axial direction through free-electron two- quantum Stark radiation. We find that laser radiation takes place only at the expense of the axial kinetic energy when Aw 〈〈 c/（ωc/γ）, where ωc/γ is the relativistic electron--cyclotron frequency. We formulate the laser power based on quantum-wiggler electrodynamics, and envision a laser of length lore with estimated power 0.1 GW/（kA） in the 10-4 cm wavelength range.

关键词： of on in that Electron-Cyclotron Laser Using Free-Electron Two-Quantum Stark Radiation in a Strong Uniform Axial Magnetic Field and an Alternating Axial Electric Field in a Voltage-Supplied Pill-Box Cavity is Stark

CO_2 laser-micro plasma arc hybrid welding for galvanized steel sheets

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2011年第A01期21卷 47-53页

作者： C.h.kim Y.N.AhN J.h.kim Advance Welding & Joining Research Group Korea Institute of Industrial Technology Incheon 406-840 South Korea

A laser lap welding process for zinc-coated steel has a well-known unsolved problem-porosity formation. The boiling temperature of coated zinc is lower than the melting temperature of the base metal, which is steel. In the autogenous laser welding, the zinc vapor generates from the lapped surfaces expels the molten pool and the expulsion causes numerous weld defects, such as spatters and blow holes on the weld surface and porosity inside the welds. The laser-arc hybrid welding was suggested as an alternative method for the laser lap welding because the arc can preheat or post-beat the weldment according to the arrangement of the laser beam and the arc. CO2 laser-micro plasma hybrid welding was applied to the lap welding of zinc-coated steel with zero-gap. The relationships among the weld quality and process parameters of the laser-arc arrangement, and the laser-arc interspacing distance and arc current were investigated using a full-factorial experimental design. The effect of laser-arc arrangement is dominant because the leading plasma arc partially melts the upper steel sheets and vaporizes or oxidizes the coated zinc on the lapped surfaces. Compared with the result from the laser-TIG hybrid welding, the heat input from arc can be reduced by 40%.

关键词： galvanized steel CO2 laser micro plasma hybrid welding

Microbiota or short-chain fatty acids: which regulates diabetes?

在线全文

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2018年第2期15卷 88-91页

作者： Chang h kim Department of Comparative Pathobiology and Biological Sciences Laboratory of Immunology and HematopoiesisWeldon School of Biomedical EngineeringPurdue Institute of InflammationImmunology and Infectious DiseasesPurdue Center for Cancer ResearchPurdue UniversityWest Lafayette47907INUSA

Diabetes mellitus,with sustained high-sugar levels in the blood,has been steadily rising in prevalence *** 12–14%of the US population has been diagnosed with diabetes in recent years.1 One major reason for the rise of diabetes is dietary *** consumption of processed carbohydrates with inadequate consumption of dietary fiber(DF)has been recognized as a major risk factor for diabetes,as hypothesized several decades ago by Trowell.

关键词： diabetes sustained dietary

Measuring nanoscale friction at graphene step edges

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Friction 2020年第4期8卷 802-811页

作者： Zhe ChEN Seong h.kim Department of Chemical Engineering and Materials Research Institute Pennsylvania State UniversityUniversity ParkPA 16802USA

Although graphene is well known for super-lubricity on its basal plane, friction at its step edge is not well understood and contradictory friction behaviors have been reported. In this study, friction of mono-layer thick graphene step edges was studied using atomic force microscopy (AFM) with a Si tip in dry nitrogen atmosphere. It is found that, when the tip slides over a'buried' graphene step edge, there is a resistive force during the step-up motion and an assistive force during the step-down motion due to the topographic height change. The magnitude of these two forces is small and the same in both step-up and step-down motions. As for the'exposed' graphene step edge, friction increases in magnitude and exhibits more complicated behaviors. During the step-down motion of the tip over the exposed step edge, both resistive and assistive components can be detected in the lateral force signal of AFM if the scan resolution is sufficiently high. The resistive component is attributed to chemical interactions between the functional groups at the tip and step-edge surfaces, and the assistive component is due to the topographic effect, same as the case of buried step edge. If a blunt tip is used, the distinct effects of these two components become more prominent. In the step-up scan direction, the blunt tip appears to have two separate topographic effects–elastic deformation of the contact region at the bottom of the tip due to the substrate height change at the step edge and tilting of the tip while the vertical position of the cantilever (the end of the tip) ascends from the lower terrace to the upper terrace. The high-resolution measurement of friction behaviors at graphene step edges will further enrich understanding of interfacial friction behaviors on graphene-covered surfaces.

关键词： friction graphene step edge atomic force microscopy tip bluntness

Effects of Weaving Laser on Weld Microstructure and Crack for Al 6k21-T4 Alloy

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2011年第1期27卷 93-96页

作者： B.h.kim N.h.Kang W.T.Oh C.h.kim J.h.kim Y.S.kim Y.h.Park Department of Materials Science and Engineering Pusan National UniversitySan30Jangjeon-dongGeumjeong-guBusan 609-735Korea Department of Materials and Components Engineering Dong-Eui UniversityBusan 614-714Korea Advanced Joining Technology Team KITECH7-47Songdo-dongYeonsu-guIncheon 406-840Korea Division for Dongnam Area Technology Service KITECHJisa-dongGanseo-guBusan 618-230Korea

For Al 6k21-T4 overlap weld joint,the shear-tensile strength by using the weaving laser was improved as compared to the case of linear *** the specimen of low strength,the porosity was distributed continuously along the intersection between the plates and fusion ***,for the optimized welding condition,large oval-shaped porosities were located only in the advancing track of the concave ***,the continuity of cracks and porosities played a key role to determine the ***,the weaving width was also the important parameter to control the ***,the concave part had more significant hot and cold cracking in the weld and heat-affected zone（hAZ）,respectively,than the convex part.

关键词： Weaving laser Weld microstructure Void Al alloy

Complex regulatory effects of gut microbial short-chain fatty acids on immune tolerance and autoimmunity

在线全文

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2023年第4期20卷 341-350页

作者： Chang h.kim Department of Pathology University of Michigan School of MedicineAnn ArborMI48109USA Mary h.Weiser Food Allergy Center Center for Gastrointestinal Researchand Rogel Center for Can

Immune tolerance deletes or suppresses autoreactive lymphocytes and is established at multiple levels during the development,activation and effector phases of T and B *** mechanisms are cell-intrinsically programmed and critical in preventing autoimmune *** have witnessed the existence of another type of immune tolerance mechanism that is shaped by lifestyle choices,such as diet,microbiome and microbial ***-chain fatty acids(SCFAs)are the most abundant microbial metabolites in the colonic lumen and are mainly produced by the microbial fermentation of prebiotics,such as dietary *** review focuses on the preventive and immunomodulatory effects of SCFAs on *** tissue-and disease-specific effects of dietary fiber,SCFAs and SCFA-producing microbes on major types of autoimmune diseases,including type I diabetes,multiple sclerosis,rheumatoid arthritis and lupus,are ***,their key regulatory mechanisms for lymphocyte development,tissue barrier function,host metabolism,immunity,autoantibody production,and inflammatory effector and regulatory lymphocytes are *** shared and differential effects of SCFAs on different types and stages of autoimmune diseases are discussed.

关键词： Short-chain fatty acids Immune tolerance Diabetes mellitus Rheumatoid arthritis Lupus Multiple sclerosis

Control of lymphocyte functions by gut microbiota-derived short-chain fatty acids

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2021年第5期18卷 1161-1171页

作者： Chang h.kim Department of Pathology and Mary h.Weiser Food Allergy Center University of Michigan School of MedicineAnn ArborMIUSA

A mounting body of evidence indicates that dietary fiber(DF)metabolites produced by commensal bacteria play essential roles in balancing the immune ***,considered nonessential nutrients in the past,is now considered to be necessary to maintain adequate levels of immunity and suppress inflammatory and allergic ***-chain fatty acids(SCFAs),such as acetate,propionate,and butyrate,are the major DF metabolites and mostly produced by specialized commensal bacteria that are capable of breaking down DF into simpler saccharides and further metabolizing the saccharides into *** act on many cell types to regulate a number of important biological processes,including host metabolism,intestinal functions,and immunity *** review specifically highlights the regulatory functions of DF and SCFAs in the immune system with a focus on major innate and adaptive *** information regarding how SCFAs regulate innate lymphoid cells,T helper cells,cytotoxic T cells,and B cells and how these functions impact immunity,inflammation,and allergic responses are discussed.

关键词： Microbiota Dietary fiber Short-chain fatty acids Innate lymphoid cells B cells Th1 Th17 Tregs CD8 Microbial metabolites