• 한국세라믹학회지
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• 제46권5호
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• pp.497-504
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• 2009

DLC is considered as the candidate material for application of moving parts in automotive components relatively in high pressure and temperature operating conditions for its high hardness with self lubrication and chemical inertness. Different deposition method such as arc plating, ion gun plating and PECVD were used for comparing mechanical and tribological properties of each DLCs deposited on stainless steel with 1 um thick respectively. Among these 3 types of DLCs, the arc plated DLC film showed highest value for wear resistance in dry condition. From the results of analysis for physical properties of DLC films, it seems that the adhesion force and crack initiation modes were more important factors than intrinsic mechanical properties such as hardness, elastic modulus and/or roughness to the wear resistance of DLC films. Raman spectroscopy was used for understanding chemical bonding natures of each type of DLC films. Typical D and G peaks were identified based on the deposition method. Hardness of the coating layers were identified by nanoindentation method and the adhesions were checked by scratch method.

• Corrosion Science and Technology
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• 제10권2호
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• pp.65-70
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• 2011

DLC is considered as the candidate material for application of moving parts in automotive components relatively in high pressure and temperature operating conditions for its high hardness with self lubrication and chemical inertness. The properties of interlayer between the substrate and the DLC film were studied. Arc ion plating method have been employed to deposit onto substrate and sputtering method was used for synthesizing DLC onto interlayer. Among these six types of interlayer, deposited DLC film onto TiCN showed excellent value for characteristics. From the results of analysis for physical properties of DLC films, it seems that the adhesion forces were more important factors than intrinsic mechanical properties such as hardness, roughness and wear resistance of DLC films. AFM(Atomic Force Microscope) was used for understanding roughness of DLC films. Hardnesses of the coating layers were identified by nano-indentation method and adhesions were checked by scratch method.

• 한국정밀공학회지
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• 제25권6호
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• pp.150-158
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• 2008

This research considered that the significance of the NT(Nano Technology) which gradually increased the importance of it and investigated the technology development current situation of the Korea, U.S.A, Japanese, Europe. Therefore, in domestic and foreign, this research was widely used. It includes the tendency of the technology about processing methods using the ion beam and electron beam among the In-line system related technique field for the high efficiency energy beam application nano scale manufacturing components. The technique level of Korea, the international trend of technology and cooperation research present condition are dealt in. The information about the checked out of business of research and development of the country consistency and policy establishment try to be provided.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2019년도 전력전자학술대회
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• pp.459-460
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• 2019

The performance dynamics of battery is very sensitive to operating conditions (i.e temperature, load current, and state of charge). A model developed based on certain conditions may perform well under the similar conditions but can not accurately predict the performance for changing conditions. Thus, a generalized model is needed which can accurately emulate the battery dynamic behavior under all conditions. In addition, the components of the model should relate to the physicochemical processes that occur inside the battery. Electrochemical impedance curve shows better visible reflection of the processes inside battery as compared to voltage curve. The model trained for parameterization using neural network has better generalization than simple curve fitting. Thus, this study proposes recurrent neural network based parameterization of the Lithium ion battery model followed by impedance based identification.

• Nuclear Engineering and Technology
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• 제54권6호
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• pp.2334-2337
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• 2022

Deuterium-tritium reaction is the most promising one in term of the highest nuclear fusion cross-section for the reactor. So it is one of urgent issues to develop materials and components that are simultaneously resistant to high heat flux and high energy neutron flux in realization of the fusion energy. 2.45 MeV neutron production was reported in D-D reaction in KSTAR and regarded as beam-target is the dominant process. The feasibility study of KSTAR to wide area neutron source facility is done in term of D-D and D-T reactions from the empirical scaling law from the mixed fast and thermal stored energy and its projection to cases of heating power upgrade and DT reaction is done.

• International Journal of Korean Welding Society
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• 제3권2호
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• pp.29-39
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• 2003

The durability and reliability of thermal barrier coatings (TBCs) play an important role in the service reliability, availability and maintainability (RAM) of hot­section components in advanced turbine engines for aero and utility applications. Photostimulated luminescence spectroscopy (PSLS) and electrochemical impedance spectroscopy (EIS) are being concurrently developed as complimentary non­destructive evaluation (NDE) techniques for quality control and life­remain assessment of TBCs. This paper overviews the governing principles and applications of the luminescence and the impedance examined in the light of residual stress, phase constituents and resistance (or capacitance) in TBC constituents including the thermally grown oxide (TGO) scale. Results from NDE by PSLS and EIS are discussed and related to the microstructural development during high temperature thermal cycling, examined by using a variety of microscopic techniques including focused ion beam (FIB) in­situ lift­out (INLO), transmission and scanning transmission electron microscopy (TEM and STEM).

• 한국토양비료학회지
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• 제34권4호
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• pp.237-244
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• 2001

토양의 하전특성을 평가하는 데 이용되는 이온흡착법에서 지표이온이 달라졌을 때 측정되는 표면전하량의 차이를 파악하기 위하여, 화강암을 모재로 하는 논토양(지산통, 사촌통)과 밭토양(상주통, 백산통)에 $Na^+$와 $K^+$ 이온을 지표이온으로 하는 이온흡착법을 적용하였다. 표면 음전하는 모든 pH에서 직선적으로 증가하는 경향을 보였고, 표면 양전하는 pH6 이하에서만 미량으로 발현되고 중성 이상에서는 거의 발현되지 않았다. 또, NaCl이 지표이온종인 경우 KCl을 사용하여 측정한 표면전하량에 비해 측정된 모든 pH 범위에서 상대적으로 낮은 전하밀도값을 나타내었다. 이러한 차이는 지표이온종의 수화반경에 따른 표면 흡착강도 차에 기인하는 것으로 판단된다. 지산, 사촌, 백산통의 표면전하량은 pH에 따라 $0.21{\sim}9.01cmol_c{\cdot}kg^{-1}$의 범위 내에 존재하였으며, 통일한 pH에서는 백산통의 표면전하 밀도가 다른 토양에 비하여 가장 높게 나타났다. 본 연구에서 분석된 토양의 pH 변화에 따른 전하변화량(dCEC/dpH)은 가변전하를 발현시키는 토양구성물 중 유기물에 의하여 가장 크게 변화하는 것으로 나타났다.

• Mass Spectrometry Letters
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• 제14권4호
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• pp.153-159
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• 2023

The copper ion, Cu(II), binding sites for amyloid fragment Aβ1-16 (=Aβ16 ) were investigated to explain the biological activity difference in the Aβ16 aggregation process. The [M+Cu+(z-2)H]^z+ (z = 2, 3 and 4, M = Aβ16 monomer) and [D+Cu+(z-2)H]^z+ (z = 3 and 5, D = Aβ16 dimer) structures were investigated using electrospray ionization (ESI) mass spectrometry (MS) and tandem mass spectrometry (MS/MS). Fragment ions of the [M+Cu+(z-2)H]^z+ and [D+Cu+(z-2)H]^z+ complexes were observed using collision-induced dissociation MS/MS. Three different fragmentation patterns (fragment "a", "b", and "y" ion series) were observed in the MS/MS spectrum of the (Aβ16 monomer or dimer-Cu) complex, with the "b" and "y" ion series regularly observed. The "a" ion series was not observed in the MS/MS spectrum of the [M+Cu+2H]⁴⁺ complex. In the non-covalent bond dissociation process, the [D+Cu+3H]⁵⁺ complex separated into three components ([M+Cu+H]³⁺, M³⁺, and M²⁺), and the [M+Cu]²⁺ subunit was not observed. The {M + fragment ion of [M+Cu+H]³⁺} fragmentation pattern was observed during the covalent bond dissociation of the [D+Cu +3H]⁵⁺ complex. The {M + [M+Cu+H]³⁺} complex geometry was assumed to be stable in the [D+Cu+3H]⁵⁺ complex. The {M + fragment ion of [M+Cu]²⁺} fragmentation pattern was also observed in the MS/MS spectrum of the [D+Cu+H]³⁺ complex. The {M + [y₉+Cu]¹⁺} fragment ion was the characteristic fragment ion. The [D+Cu+H]³⁺ and [D+Cu+3H]⁵⁺ complexes were likely to form a monomer-monomer-Cu (M-M-Cu) structure instead of a monomer-Cu-monomer (M-Cu-M) structure.

• Clinical and Experimental Reproductive Medicine
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• 제24권1호
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• pp.67-81
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• 1997

To determine the concentration and the physiologic role of metal components in blood plasma and seminal plasma in relation to male infertility, the concentrations of twelve metal components in blood plasma and seminal plasma including Na, Mg, K, Ca, Cr, Mn, Fe, Cu, Zn, Se, Cd and Pb were measured by atomic absorbance spectrophotometery or ion selective electrode analysis. Semen and blood samples were obtained from a total of 110 men including 70 male infertility patients, 20 vasectomized persons and 20 fertility proven volunteers visited to the Male Infertility Clinic of Pusan National University Hospital. The concentrations of Ca, Zn, Mg, Cr and Cd in control group were higher in seminal plasma than in blood plasma, and additionally Pb were higher in infertility group. The concentrations of all metal components revealed no significant difference according to patients' age, resident, occupation, sperm density, motility and hormone level in blood plasma, but some metal components including Ca, Mg, Cu, Mn, Cd and Pb revealed a significant difference according to each these parameters except patient's age in seminal plasma. The concentrations of Mn, Cd and Pb in the vasectomy persons were higher than in the infertility group III including testicular and epididymal factors, but not in blood plasma. We conclude that the quantitative changes of metal components in the seminal plasma may have effects on not only spermatogenesis and sperm function, but also contribute to diagnostic parameter according to organ specificity of the metal in the male reproduction.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 춘계학술발표회
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• pp.61-61
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• 2018

Buckwheat is a important vegetable in asia for long time. Recently, Buckwheat has attracted attention to its potential for health benefit and especially as a gluten-free food. Conventional buckwheat studies have focused on seeds and sprouts, but we studied the components of the aerial parts and roots of buckwheat after harvesting. Therefore, we hope that this research will be a basic study to expand the application range of buckwheat plants which are discarded after harvesting. The ethanol extracts of aerial part and roots of buckwheat (Daegwan, Yangjul) were analysed using high performance liquid chromatography (HPLC). Rutin was detected as the major compound in Daegwan, Yangjul aerial part and Daegwan root extracts, except yangjul root extract. So we analysed Yangjul root extract using liquid chromatography-mass spectrometry (LC-MS) and then obtained the informations about the components in Yangjul root extract. Yangjul root extract was analysed by $LC-MS^n$ in negative ESI mode within the range m/z 150-2000 amu. Totally, four components was found in the Yangjul root extract and obtained the fragments ion patterns of ones. Further study, we have to confirm the structure of components in Yangjul root extract and try to more biological activity test the components for development as useful food or cosmetic ingredients.