检索结果-南通市图书馆

Ru/NiMnB spherical cluster pillar for highly proficient green hydrogen electrocatalyst at high current density

维普期刊数据库评论

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 397-408页

作者： Md Ahasan Habib Shusen Lin Mehedi Hasan joni Sumiya Akter Dristy Rutuja Mandavkar jae-hun Jeong Jihoon Lee Department of Electronic Engineering College of Electronics and Information Kwangwoon University

Advanced OER/HER electrocatalytic alternatives are crucial for the wide adaptation of green hydrogen ***,Ru/NiMnB spherical cluster pillar （SCP）,denoted as Ru/NiMnB,is synthesized using a combination of electro-deposition and hydrothermal *** investigation of Ru doping in the NiMnB matrix revealed significant improvements in electrocatalytic *** Ru/NiMnB SCPs demonstrate superior OER/HER activity with low overpotentials of 150 and 103 mV at 50mA/cm2in 1 M KOH,making them highly competitive with state-of-the-art ***,the Ru/NiMnB SCPs exhibit a low 2-E cell voltage of 2.80 V at ultra-high current density of 2,000 m A/cm2in 1 M KOH,outperforming the standard benchmark electrodes of RuO2||Pt/C,thereby positioning Ru/NiMnB as one of the best bifunctional *** SCPs exhibit exceptional high-current characteristics,stability and corrosion resistance,as evidenced by continuous operation at 1,000 mA/cm2high-current density for over 150 h in 6 M KOH at elevated temperatures under harsh industrial *** a small amount of Ru incorporation significantly enhances the electrocatalytic performances of NiMnB,attributed to increased active sites and improved intrinsic properties such as conductivity,adsorption/desorption capability and reaction ***,Ru/NiMnB SCPs present a promising bi-functional electrode concept for efficient green H2production.

关键词： Advanced electrocatalyst High current Corrosion resistance Industrial requirement

Observation of baroclinic eddies southeast of Okinawa Island

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2008年第12期51卷 1802-1812页

作者： PARK jae-hun Graduate School of Oceanography University of Rhode Island

In the region southeast of Okinawa, during May to July 2001, a cyclonic and an anticyclonic eddy were observed from combined measurements of hydrocasts, an upward-looking moored acoustic Doppler current profiler (MADCP), pressure-recording inverted echo sounders (PIESs), satellite altimetry, and a coastal tide gauge. The hydrographic data showed that the lowest/highest temperature (T) and salinity (S) anomalies from a 13-year mean for the same season were respectively ?3.0/+2.5°C and ?0.20/+0.15 psu at 380/500 dbar for the cyclonic/anticyclonic eddies. From the PIES data, using a gravest empirical mode method, we estimated time-varying surface dynamic height (D) anomaly referred to 2000 dbar changing from ?20 to 30 cm, and time-varying T and S anomalies at 500 dbar ranging through about ±2 and°C ±0.2 psu, respectively. The passage of the eddies caused variations of both satellite-measured sea surface height anomaly (SSHA) and tide-gauge-measured sea level anomaly to change from about ?20 to 30 cm, consistent with the D anomaly from the PIESs. Bottom pressure sensors measured no variation related to these eddy activities, which indicated that the two eddies were dominated by baro-clinicity. Time series of SSHA map confirmed that the two eddies, originating from the North Pacific Subtropical Countercurrent region near 20°–30°N and 150°–160°E, traveled about 3000 km for about 18 months with mean westward propagation speed of about 6 cm/s, before arriving at the region southeast of Okinawa Island.

关键词： baroclinic eddy southeast of Okinawa Island PIES ADCP

A new damage quantification approach for shear-wall buildings using ambient vibration data

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2015年第1期9卷 17-25页

作者： Seung-hun SUNG Hyung-jo JUNG Department of Civil and Environmental Engineering Korea Advanced Institute of Science and Technology Daejeon 305- 701 Korea

This paper presents a new approach to estimate damage seventy tor slaear-wall DUlltllngs using alagona~ terms of a modal flexibility matrix estimated from dynamic properties. This study aims to provide a fundamental concept for quantifying the damage of realistic buildings by investigating an idealized shear-wall building. Numerical studies were performed on a 5-story shear-wall building model to validate the applicability of the presented approach, using two damage patterns. With the numerical simulations, the proposed approach accurately determined the damage ratio of the specimens. Experiments were also conducted on a 5-story shear-wall building model for which the system parameters were almost the same as those in numerical simulations. The estimated damage-quantification results from the experimental validations demonstrated that the performance of the presented method for shear-wall buildings was both suitable and accurate.

关键词： damage identification modal flexibility damage quantification shear-wall buildings

Improved Photoresponse of UV Photodetectors by the Incorporation of Plasmonic Nanoparticles on Ga N Through the Resonant Coupling of Localized Surface Plasmon Resonance

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2020年第7期12卷 175-190页

作者： Sundar Kunwar Sanchaya Pandit jae-hun Jeong Jihoon Lee Department of Electronic Engineering College of Electronics and InformationKwangwoon University

Very small metallic nanostructures,i.e.,plasmonic nanoparticles(NPs),can demonstrate the localized surface plasmon resonance(LSPR)e ect,a characteristic of the strong light absorption,scattering and localized electromagnetic field via the collective oscillation of surface electrons upon on the excitation by the incident *** LSPR of plasmonic NPs can significantly improve the photoresponse of the *** this work,significantly enhanced photoresponse of UV photodetectors is demonstrated by the incorporation of various plasmonic NPs in the detector *** size and elemental composition of monometallic Ag and Au NPs,as well as bimetallic alloy Ag Au NPs,are fabricated on Ga N(0001)by the solid-state dewetting *** photoresponse of various NPs are tailored based on the geometric and elemental evolution of NPs,resulting in the highly enhanced photoresponsivity of 112 A W-1,detectivity of 2.4×1012 jones and external quantum e ciency of 3.6×104%with the high Ag percentage of Ag Au alloy NPs at a low bias of 0.1 *** Ag Au alloy NP detector also demonstrates a fast photoresponse with the relatively short rise and fall time of less than 160 and 630 ms,*** improved photoresponse with the Ag Au alloy NPs is correlated with the simultaneous e ect of strong plasmon absorption and scattering,increased injection of hot electrons into the Ga N conduction band and reduced barrier height at the alloy NPs/Ga N interface.

关键词： UV photodetection NP-based photodetectors Nanoparticles Plasmonic enhancement

Animal models of axon regeneration after spinal cord injury

在线全文

学校读者我要写书评

暂无评论

Neuroscience Bulletin 2013年第4期29卷 436-444页

作者： Do-hun Lee jae K. Lee University of Miami School of Medicine Miami Project to Cure Paralysis Department of Neurological Surgery

With advances in genetic and imaging techniques, investigating axon regeneration after spinal cord injury in vivo is becoming more common in the literature. However, there are many issues to consider when using animal models of axon regeneration, including species, strains and injury models. No single particular model suits all types of experiments and each hypothesis being tested requires careful selection of the appropriate animal model. In this review, we describe several commonly-used animal models of axon regeneration in the spinal cord and discuss their advantages and disadvantages.

关键词： pyramidotomy strain differences contusion injury models

Segregation of voiced and unvoiced components from residual of speech signal

在线全文

学校读者我要写书评

暂无评论

journal of Central South University 2012年第2期19卷 496-503页

作者： jo Cheol-woo KIM jae-hee School of Mechatronics Changwon National University

In conventional source-filter models, voiced and unvoiced components were considered independently. However, in practice it was difficult to separate the source into two parts. An actual source consists of a mixture of two sources and the ratio varies according to the content or the intention of speaker. It had been investigated to separate the voiced and unvoiced components for different source models. Source signals were modeled based on the residual signal measured from inverse filtering. Three different source models were assumed. The parameters of each model were optimized for the original speech signal using a genetic algorithm. The resulting parameters were compared in terms of the mel-cepstral distance to the original signal, the spectrogram and the spectral envelope from the synthesized signal. The optimization method achieves an improvement of 15% for the Klatt model, but there is little improvement in the modified residual case.

关键词： voice source model synthesis optimization genetic algorithm

Collocation Methods for Hyperbolic Partial Differential Equations with Singular Sources

在线全文

学校读者我要写书评

暂无评论

Advances in Applied Mathematics and Mechanics 2009年第6期1卷 769-780页

作者： jae-hun Jung Wai Sun Don Department of Mathematics the State University of New York at BuffaloBuffaloNY 14260-2900USA Department of Mathematics Hong Kong Baptist UniversityHong KongChina

A numerical study is given on the spectral methods and the high order WENO finite difference scheme for the solution of linear and nonlinear hyperbolic partial differential equations with stationary and non-stationary singular *** singular source term is represented by theδ-*** the approximation of theδ-function,the direct projection method is used that was proposed in[6].Theδ-function is constructed in a consistent way to the derivative *** sine-Gordon equation with a stationary singular source was solved with the Chebyshev collocation ***δ-function with the spectral method is highly oscillatory but yields good results with small number of collocation *** results are compared with those computed by the second order finite difference *** modeling general hyperbolic equations with a non-stationary singular source,however,the solution of the linear scalar wave equation with the nonstationary singular source using the direct projection method yields non-physical oscillations for both the spectral method and the WENO *** numerical artifacts arising when the non-stationary singular source term is considered on the discrete grids are explained.

关键词： Singular sources Dirac-δ-function Direct projection method Chebyshev collocation method WENO scheme

Controlling a lithium surface with an alkyl halide nucleophile exchange

维普期刊数据库评论

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 2021年第11期30卷 617-626,I0015页

作者： Jung-hun Lee Thuy Hoai Linh Vuong Soo Min Hwang jae-hun Kim Young-Jun Kim SKKU Advanced Institute of Nanotechnology(SAINT) Sungkyunkwan UniversitySuwon 16419Republic of Korea Department of Nano Engineering Sungkyunkwan UniversitySuwon 16419Republic of Korea School of Materials Science and Engineering Kookmin UniversitySeoul 02707Republic of Korea

Despite its high theoretical energy density, lithium metal faces huge challenges in its implementation as an anode for Li secondary batteries because of its uncontrollable dendritic growth and large volume change during plating/stripping processes. These geometric changes cause degradation in a cell’s cycle life and performance and can lead to short-circuits and explosions. Here, we report a new approach to producing a LiF-rich phase on the lithium anode surface by employing a “bi-phase” separator. We fabricated it by coating polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) onto a cellulose separator. The coverage of coating was adjusted by varying its concentration in the coating solution. The combination of cellulose and PVDF-HFP produced a LiF-rich solid-electrolyte interphase layer on the Li metal surface via an alkyl halide nucleophile exchange in contact with the bi-phase separator during plating. Symmetric cell tests show that the bi-phase separator extends the cycle life by more than 300 h, with overpotentials of less than 100 mV under plating/stripping at 2 mA cm^(−2) for a capacity of 2 mAh cm^(−2). The formation mechanism of the LiF-rich phase is suggested from spectroscopic analyses.

关键词： Li metal anode PVDF-HFP Cellulose LiF Phase inversion

Sodium nitrite-derived nitric oxide protects rat testes against ischemia/reperfusion injury

在线全文

学校读者我要写书评

暂无评论

Asian journal of Andrology 2019年第1期21卷 92-97页

作者： jae Won Lee Dong-hun Lee jae Keun Park Jin Soo Han Center for Convergence Bioceramic Materials Korea Institute of Ceramic Engineering and TechnologyChungcheongbuk-do 28160Korea Department of Awan Diseases Laboratory College of Veterinary MedicineKonkuk UniversitySeoul 05029Korea Viral Pathogenesls Section Laboratory of Infectious DiseasesNational Institute of Allergy and infectious DiseasesNational institutes of HealthBethesdaMD 20892USA The institute for the 3Rs & Department of Laboratory Animal Medicine College of Veterinary Medicine and Veterinary Science Research instituteKonkuk UniversitySeoul 05029Korea.

Testicular torsion,a common urologic emergency,is primarily caused by ischemia/reperfusion (I/R)injury of the *** oxide (NO)-derived from nitrite (NO2-)has been reported to have prominent therapeutic effects on I/R injury in the heart,liver,and brain;however,its effects on testicular I/R injury have not been *** study,therefore,investigated whether NO from NO2^-is beneficial in a rat model of testicular I/R injury which eventually results in impaired *** Sprague-Dawley rats were assigned to the following seven groups:group A,sham-operated control group;Group B,I/R with no treatment;Groups C, D,and E,I/R followed by treatment with three different doses of NO2^-;Group F,I/R followed by administration of NO2-and NO scavenger (2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide potassium salt [C-PTIO]);and Group G,I/R followed by administration of nitrate (NO3^-).NO2^-,NO3^-,and C-PTIO were intravenously *** examination of the testes and the western blot analysis of caspase-3 were *** of antioxidant enzymes and lipid peroxidation were measured. Germ cell apoptosis,oxidative stress,antioxidant enzymatic function,and lipid peroxidation in Group B were significantly higher than those in Group *** B exhibited an abnormal testicular morphology and impaired *** contrast,testicular damages were attenuated in the NO2^-treatment groups,which were caused by reduction in superoxide and peroxynitrite levels and an inhibition of caspase-3-dependent *** results of this study suggest NO2^-to be a promising therapeutic agent with anti-oxidant and anti-apoptotic properties in testicular I/R injury.

关键词： ischemia/reperfusion injury nitric oxide nitrite rat testis