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Chinese Journal of Chemical Physics 2008年第3期21卷 193-201页

作者： Xi Xing Beth Reed Mi Kyung Bahng Peng Wang Hin Koo Woo sun jong baek Chee Shing Lain Cheuk Yiu Ng Department of Chemistry University of California Davis Davis California 95616 USA

We show that by scanning the frequency of a single mode infrared （IR） optical parametric oscillator （IR- OPO） laser to excite the molecular species of interest and fixing the frequency of a vacuum ultraviolet （VUV） laser to photoionize the IR excited species, high-resolution IR spectra of polyatomic neutrals can be obtained with high sensitivity. The fact that this IR-VUV-photoion （IR-VUV-PI） method is based on VUV photoionization probe, and thus, allows the identification of the neutral IR absorber, makes it applicable for IR spectroscopy measurements of isotopemers, radicals, and clusters, which usually exist as impure samples. The highly resolved IR-VUV-PI measurements achieved using the single mode IR-OPO laser have made possible the selection of single rovibrational states of CH3X （X=Br and I）, C2H4, and C3H4 for VUV-pulsed field ionization-photoelectron （VUV-PFI-PE） measurements, resulting in rovibrationally resolved photoelectron spectra for these polyatomic molecules. These experiments show that the signal- to-noise ratios of the IR-VUV-PI and IR-VUV-PFI-PE spectra obtained by employing the high-resolution IR-OPO laser are significantly higher than those observed in previous IR-VUV-PI and IR-VUV-PFI-PE studies using a low-resolution IR-OPO laser. Further improvement in sensitivity of IR-VUV-PI and IR- VUV-PFI-PE measurements by using the collinear arrangement of IR-VUV lasers and molecular beam is discussed.

关键词： Vacuum ultraviolet Infrared Pulse-field photoelectron High resolution

Effect of Squeeze Cast Process Parameters on Fluidity of Hypereutectic Al-Si Alloy

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Journal of Materials Science & Technology 2008年第1期24卷 7-11页

作者： jong-Kyu baek Hae-Wook Kwon School of Materials Science and Engineering Yeungnam University Gyeongsan 712-749 Korea

The effects of processing variables on the fluidity of hypereutectic Al-Si alloy melt during squeeze casting were *** maximum fluidity of Al-16.0%Si alloy during squeeze casting was obtained under the applied pressure of 30 *** fluidity increased with *** fluidity increased with silicon content in the range from 12.0% to 20.0%.That was decreased respectively by eutectic modification and primary silicon refinement.

关键词： Squeeze casting Al-alloy Fluidity Melt treatment

Wavelet Estimation in Heteroscedastic Model Under Censored Samples

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2253-2268页

作者： Han Ying LIANG jong IL baek Department of Mathematics Tongji University Shanghai 200092 P. R. China School of Mathematics & Informational Statistics and Institute of Basic Natural Science Wonkwang University Ik-San 570-749 South Korea

Consider the heteroscedastic regression model Yi = g（xi）＋ σiei, 1 ≤ i ≤ n, where σi^2 = f（ui）, here （xi, ui） being fixed design points, g and f being unknown functions defined on [0, 1], ei being independent random errors with mean zero. Assuming that Yi are censored randomly and the censored distribution function is known or unknown, we discuss the rates of strong uniformly convergence for wavelet estimators of g and f, respectively. Also, the asymptotic normality for the wavelet estimators of g is investigated.

关键词： censored sample heteroscedastic regression model wavelet estimator strong unform convergence rate asymptotic normality

Cool white light and tunable multicolor emission from Tb^(3+)/Dy^(3+)co-activated glasses under different excitations for WLEDs

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Journal of Rare Earths 2024年第1期42卷 46-56,I0002页

作者： L.Vijayalakshmi K.Naveen Kumar jong Dae baek Department of Automotive Engineering Yeungnam UniversityGyeongsanGyeongbuk38541Republic of Korea Department of Mechanical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea

A set of co-doped(Tb^(3+)/Dy^(3+))lithium zinc borate(LZB)glasses were developed by melt *** structural evaluation was performed for synthesized glassy *** Dy^(3+)and Tb^(3+)individually doped glasses exhibit intense yellow and green luminescence bands at 575 nm(^(4)F_(9/2)→^(6)H_(13/2))and543 nm(^(5)D_(4)→^(7)F_(5)),*** sensitization effect of Dy^(3+)on Tb^(3+)was analyzed by increasing the Tb^(3+)content with respect to the optimum Dy^(3+)content(0.5 mol%)in Dy^(3+)/Tb^(3+).The spectral overlay of Dy^(3+)luminescence and Tb^(3+)absorption profiles,Dy^(3+)/Tb^(3+)PL spectra under different excitations 352,362,376,and 385 nm,shortening decay lifetimes of Dy^(3+)in Dy^(3+)/Tb^(3+)co-activated glasses,energy transfer(ET)parameters,chromaticity coordinates and their corresponding correlated temperatures all help to explain ET from Dy^(3+)to Tb^(3+).At 385 nm of Dy^(3+)excitation,the optimized co-activated(0.5Dy^(3+)+1.0Tb^(3+)):LZB glass displays cool white light *** non-radiative ET from Dy^(3+)to Tb^(3+)is dominated by electric dipole-dipole interaction and its ET efficiency was calculated to be 63%.At the same time,reverse ET from Tb^(3+)to Dy^(3+)was also *** shift in color coordinates from dominant yellow to greenish-yellow,green and white light emission suggests that Dy^(3+)/Tb^(3+)coactivated LZB glasses can be a potential candidate for UV converted multicolor and white light emitting devices.

关键词： Rare earths Photoluminescence Energy transfer Spectral overlap Decay lifetime Multicolor emitting LEDs

SOME RESULTS ON GENERALIZED EQUILIBRIUM PROBLEMS INVOLVING STRICTLY PSEUDOCONTRACTIVE MAPPINGS

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Acta Mathematica Scientia 2011年第5期31卷 2041-2057页

作者： jong Kyu Kim sun Young Cho Department of Mathematics Educations Kyungnam UniversityMasan 631-701Korea Department of Mathematics Gyeongsang National UniversityChinju 660-701Korea

In this paper,we consider an iterative sequence for generalized equilibrium problems and strictly pseudocontractive *** show that the iterative sequence converges strongly to a common element of the solution set of ge... 详细信息

关键词： equilibrium problem nonexpansive mapping inverse-strongly monotone mapping strictly pseudocontractive mapping

GENERAL DECAY FOR A QUASILINEAR SYSTEM OF VISCOELASTIC EQUATIONS WITH NONLINEAR DAMPING

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Acta Mathematica Scientia 2012年第4期32卷 1321-1332页

作者： jong Yeoul Park sun Hye Park Department of Mathematics Pusan National UniversityBusan 609-735 South Korea

In this paper, we consider a system of coupled quasilinear viscoelastic equa- tions with nonlinear damping. We use the perturbed energy method to show the general decay rate estimates of energy of solutions, which extends some existing results concerning a general decay for a single equation to the case of system, and a nonlinear system of viscoelastic wave equations to a quasilinear system.

关键词： general decay coupled quasilinear equations viscoelastic equations perturbed energy method

A thorough analysis of the effect of surfactant/s on the solubility and pharmacokinetics of (S)-zaltoprofen

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Asian Journal of Pharmaceutical Sciences 2019年第4期14卷 435-444页

作者： Cuong Viet Pham jong-Suep baek jong-Hun Park Sang-Hun Jung jong-Seong Kang Cheong-Weon Cho College of Pharmacy and Institute of Drug Research and Development Chungnam National UniversityDaejeon 34134Republic of Korea Department of Herbology College of Korean MedicineDongguk UniversityGyeongju 38066Republic of Korea

Until now, there are no publications about the preformulation studies on(S)-zaltoprofen((S)-ZPF). Hence, we first investigated the solubility of(S)-ZPF, screened solubilizers and performed the pharmacokinetic study of(S)-ZPF in the presence of the solubilizers. The measurement of the solubility of(S)-ZPF in 26 different solvents was carried out, including d-alpha tocopheryl polyethylene glycol 1000 succinate(TPGS), 2-hydroxypropyl-β-cyclodextrin(HPCD), and mixtures of individual solvent. The plasma concentration of(S)-ZPF and the amount of(S)-ZPF retained in stomach were determined after oral(35.0 mg/kg) and intravenous(5.0 mg/kg) administration. The solubility of(S)-ZPF showed an increase of 484-fold in TPGS compared to its aqueous solubility. There was a significant increase of AUC 0-24 h for pure(S)-ZPF in the TPGS group(813.59 ± 64.17 μg h/ml) in comparison with AUC 0-24 h in the HPCD group(595.57 ± 71.76 μg h/ml) and water group(465.57 ± 90.89 μg h/ml). In addition, the T max of(S)-ZPF in the TPGS group was 2 h, much faster than that in the HPCD or water groups(5.50 or 5.67 h, respectively). This suggested that TPGS played a significant role in the increase of solubility and bioavailability of(S)-ZPF.

关键词： (S)-zaltoprofen Solubility Bioavailability D-alpha tocopheryl polyethylene glycol 1000 succinate 2-hydroxypropyl-β-cyclodextrin

Temperature-dependent constitutive modeling of a magnesium alloy ZEK100 sheet using crystal plasticity models combined with in situ high-energy X-ray diffraction experiment

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Journal of Magnesium and Alloys 2022年第10期10卷 2801-2816页

作者： Hyuk jong Bong Xiaohua Hu Xin sun Yang Ren Materials Deformation Department Korea Institute of Materials ScienceChangwonGyeongnam 51508South Korea Energy and Transportation Science Division Oak Ridge National LaboratoryOak RidgeTN 37831USA X-ray Science Division Argonne National LaboratoryIL 60439USA

A multiscale crystal plasticity model accounting for temperature-dependent mechanical behaviors without introducing a larger number of unknown parameters was *** model was implemented in elastic-plastic self-consistent(EPSC)and crystal plasticity finite element(CPFE)frameworks for grain-scale simulations.A computationally efficient EPSC model was first employed to estimate the critical resolved shear stress and hardening parameters of the slip and twin systems available in a hexagonal close-packed magnesium alloy,*** constitutive parameters were thereafter refined using the *** crystal plasticity frameworks incorporated with the temperature-dependent constitutive model were used to predict stress–strain curves in macroscale and lattice strains in microscale at different testing temperatures up to 200℃.In particular,the predictions by the crystal plasticity models were compared with the measured lattice strain data at the elevated temperatures by in situ high-energy X-ray diffraction,for the first *** comparison in the multiscale improved the fidelity of the developed temperature-dependent constitutive model and validated the assumption with regard to the temperature dependency of available slip and twin systems in the magnesium ***,this work provides a time-efficient and precise modeling scheme for magnesium alloys at elevated temperatures.

关键词： High-energy X-ray diffraction Crystal plasticity finite element Elastic-plastic self-consistent model Twin Temperature

Pullback attractors for the non-autonomous Benjamin-Bona-Mahony equation in unbounded domains

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Science China Mathematics 2011年第4期54卷 741-752页

作者： PARK jong Yeoul PARK sun Hye Department of Mathematics Pusan National University

The existence of a pullback attractor is proven for the non-autonomous Benjamin-Bona-Mahony equation in unbounded *** asymptotic compactness of the solution operator is obtained by the uniform estimates on the tails o... 详细信息

关键词： Benjamin-Bona-Mahony equation pullback attractor unbounded domain

Active Site Engineering in Transition Metal Based Electrocatalysts for Green Energy Applications

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Accounts of Materials Research 2021年第3期2卷 147-158页

作者： Feng Li Gao-Feng Han jong-Beom baek School of Energy and Chemical Engineering/Center for Dimension-Controllable Organic Frameworks Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919South Korea

CONSPECTUS:Hydrogen is widely considered an ideal green energy carrier and a leading candidate to replace nonrenewable fossil fuels and address serious global energy and environmental pollution *** worldwide are engaged in developing various technologies related to hydrogen energy exploitation and conversion,such as photocatalytic/electrocatalytic water splitting,fuel cells,and so *** water splitting using electric energy can produce clean and pure hydrogen from water on a large scale,which can be further directly converted into electric energy by fuel *** environmentally friendly system relies on a series of important reactions,especially the hydrogen evolution reaction(HER)and oxygen reduction reaction(ORR),which both require high efficiency and durable *** the tremendous efforts of the scientific community,electrocatalysts with satisfactory performance are still *** the heart of electrocatalysts,active sites are key to catalytic *** site engineering,by tuning the nature of the active sites in the electrocatalysts,offers an important opportunity to improve the performance of ***,the strategies for active site engineering involve(1)tailoring the environment around the active sites and(2)engineering the structure of the active *** approaches can be used to optimize the electronic properties of the active sites,balance the binding energies between the active sites and the reactants/intermediates/products,and thus accelerate the overall reaction *** this Account,we summarize the recent progress made in our laboratory on active site engineering in transition metal based electrocatalysts for green energy *** start with metal nanoparticle electrocatalysts,engineering Ru nanoparticles on different supports,to achieve more efficient electrocatalytic HER ***,after we theoretically predicted that the hydrogen adsorption/desorption o

关键词： Transition replace arrangement