• 한국식품영양과학회지
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• 제38권9호
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• pp.1284-1288
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• 2009

본 연구는 천일염 결정 내에 함유된 무기물들의 화합물 결정 상태를 비파괴적인 방법인 XRD 방법으로 규명할 수 있는지를 조사하기 위하여, 전남 서남해안의 12개 지역 염전에서 채취한 12종의 천일염들에 대하여 X선 회절선을 측정하고, 이 X선 회절선 스펙트럼을 EDX 측정 결과와 JCPDS 데이터와의 비교 분석을 통하여 천일염 결정 내에 함유된 무기물들의 화합물 결정 상태를 처음으로 확인하였다. 특히 아직까지 알려져 있지 않았던 무기질 화합물 결정들이 천일염에 함유되어 있음을 밝혀냈는데, 신안 증도와 신의의 천일염에서 $Na_2S$, 신안 비금의 천일염에서 $KMgCl_3$, 신안 도초에서 $Ca(ClO_3)_2$, 해남 송지에서 $CaAl_4O_7$, 고흥에서 $CaSiO_3$, $CaCl_2$, 해남 토판 소금에서 NaKCl 등이 관측되었다. 또한 XRD 측정 결과는 천일염의 결정구조가 소금의 입방구조인 NaCl구조를 그대로 유지함을 보였으며, 격자상수도 정제염이나 시약염에 비해 거의 변화가 없는 비슷한 값을 보였다. 그러나 FE-SEM으로부터 조사한 천일염의 외형적 결정 구조는 정제염과 시약염에서 보이는 소금 NaCl의 결정구조인 정육면체의 결정 형태와는 달리 이들이 적층되어 이루어진 결정 형태의 특징을 보였다. 또한 결정 입자의 크기에 있어서도 정제염이나 시약염보다 수백 배에 이르는 특징을 보였다.

• Tribology and Lubricants
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• 제18권4호
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• pp.260-266
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• 2002

In this study, the effects of oxide layer farmed on the wear tracks of TiN coated silicon wafer on friction and wear characteristics were investigated. Silicon wafer was used for the substrate of coated disk specimens, which were prepared by depositing TiN coating with 1 ${\mu}{\textrm}{m}$ in coating thickness. AISI 52100 steel ball was used fur the counterpart. The tests were performed both in air for forming oxide layer on the wear track and in nitrogen to avoid oxidation. This paper reports characterization of the oxide layer effects on friction and wear characteristics using X-ray diffraction(XRD), Auger electron spectroscopy(AES), scanning electron microscopy (SEM) and multi-mode atomic force microscope(AFM).

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 제35회 춘계학술대회
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• pp.310-316
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• 2002

In this study, the effects of oxide layer formed on the wear tracks of TiN coated silicon wafer on friction and wear characteristics were investigated. Silicon wafer was used for the substrate of coated disk specimens, which were prepared by depositing TiN coating with $1{\mu}m$ in coating thickness. AISI 52100 steel ball was used for the counterpart. The tests were performed both in air for forming oxide layer on the wear track and in nitrogen to avoid oxidation. This paper reports characterization of the oxide layer effects on friction and wear characteristics using X-ray diffraction (XRD). Auger electron spectroscopy (AES), scanning electron microscopy (SEM) and sliding tests.

• Advances in materials Research
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• 제1권3호
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• pp.233-243
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• 2012

Thermal reactive diffusion coating of vanadium carbide on DIN 2714 steel substrate was performed in a molten borax bath at $950-1050^{\circ}C$. The coating formed on the surface of the substrate had uniform thickness ($1-12{\mu}m$) all over the surface and the coating layer was hard (2430-2700 HV), dense, smooth and compact. The influence of the kinetics parameters, temperature and time, has been investigated. Vanadium carbide coating was characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX) and X-ray diffraction analysis (XRD). The corrosion resistance of the coating was evaluated by potentiodynamic polarization in 3.5% NaCl solution. The results obtained showed that decrease of coating microhardness following increasing time and temperature is owing to the coarsening of carbides and coating grain size.

• 보존과학회지
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• 제2권2호
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• pp.25-30
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• 1993

Materials (refractory, stone) of iron making furnace excavated from Kalcheon were investigated by the scanning electron microscopy(SEM) with an energy dispersive X-ray analysis (EDAX), X-ray fluorescence(XRF), and X-ray diffraction(XRD). Chemical composition of the refractory materials were $SiO_2(68.74\%),\;Al_2O_3(18.40\%),\;CaO(0.42\%),\;MgO(1.04\%)\;and\;K_2O(2.26\%)$ in weight ratio, which were the typical components presented in common clay. The results of chemical analysis for the stone and the glaze coated, alkali ion(K, Na, Ca) components of the glaze contained high concentration than that the stone. It was suggested that this change had a close relationship with the kinds of fuels used.

• 한국결정성장학회지
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• 제8권1호
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• pp.83-90
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• 1998

Li, K과 Na-흑연 층간화합물의 stage 전이 특성을 탄소층사이에 존재하는 intercalants의 deintercalation 메카니즘을 고려하여 제시하였다. 온도와 압력을 조절하여 합성된 Li-GICs(graphite intercalation compounds)를 분위기하에서 자발적으로 분해시켰다. 이들 화합물을 XRD 분석한 결과 1, 2 stage의 d001-값이 각각 3.71, 7.06 $\AA$으로 나타났다. 분위기하에서 Li-GiCs를 deintercalation 반응을 시킨 6주 후에 잔유화합물이 형성됨을 알 수 있었다. 또한, two-bulb 법으로 K-GICs를 합성하였으며, K-GDICs(graphite deintercalation compounds)의 구조적 안정성과 stage 전이에 대하여 조사하였다. X-선회절 결과로부터 K-GDICs는 10주 동안 안정한 K-흑연 잔유 화합물을 형성하였다. 그리고 고온, 고압법을 이용하여 합성된 1, 2stage의 Na-GICs의 deintercalation 반응과 열적 안정성에 대한 온도 의존성에 대하여 논하였다. 열적 안정성과 관련하여 Na-GICs의 구조변화를 XRD에 의하여 확인하였다. 이들 과정에 따르면 stage 전이는 무질서한 stage를 가진 GDICs의 불규칙적인 deintercalation에 의하여 형성됨을 제시할 수 있었다.

• 한국전기전자재료학회논문지
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• 제14권10호
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• pp.835-844
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• 2001

In this paper, we report the successful growth of crystalline carbon nitride films in Si(100) by a laser-electric discharge method. The laser ablation of the target leads to vapor plume plasma expending into the ambient nitrogen arc discharge area. X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy(AES) were used to identify the binding structure and the content of the nitrogen species in the deposited films. The surface morphology of the films with a deposition time of 2 hours is studied using a scanning electron microscopy (SEM). In order to determine the structural crystalline parameters, X-ray diffraction (XRD) was used to analysis the grown films.

• 한국세라믹학회지
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• 제48권2호
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• pp.147-151
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• 2011

In this study, we prepared graphene by using the modified Hummers-Offeman method and then introduced the metals (Pt, Pd and Fe) for dispersion on the surface of the graphene for synthesis of metal-graphene composites. The characterization of the prepared graphene and metal-graphene composites was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis and transmission electron microscopy (TEM). According to the results, it can be observed that the prepared graphene consists of thin stacked flakes of shapes having a well-defined multilayered structure at the edge. And the metal particles are dispersed uniformly on the surface of the graphene with an average particle size of 20 nm.

• 한국전기전자재료학회논문지
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• 제15권5호
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• pp.455-459
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• 2002

I have investigated the effects of annealing on a polymeric $\alpha-C_3N_{4.2}$ at high pressure and temperature in the presence of seeds of crystalline carbon nitride films prepared by a high voltage discharge plasma. The samples were evaluated by x-ray photoelectron spectroscopy (XPS), infrared spectroscopy, Auger electron spectroscopy and x-ray diffraction(XRD). Notably, XPS studies of the film composition before and after annealing demonstrate that the nitrogen composition in $\alpha-C_3N_{4.2}$ material initially containing more than 58% nitrogen decreases during the annealing process and reaches a common, stable composition of ~43%. XPS analysis also shows that the nitrogen composition in the annealed films without polymeric $\alpha-C_3N_{4.2}$ was reduced from 35% to 17%. Furthermore the concentration of the sp$^3$bonded phase increased with the increment of the annealing temperature.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.61-62
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• 2023

In this study, the steel slag was immersed in CO₂ nano-bubble water by Electric arc funace it was accelerated aging was reviewed through XRD analysis. The main minerals of the electric furnace oxidized slag were spinel and gehlenite, and there was no change with the number of CO₂ nano-bubbles. Minerals such as larnite, calcio-olivine, agnetite, calcite, and spinel were distributed in electrically reduced slag, and the content of calcite more than doubled with CO₂ nano-bubble immersion. Therefore, it is judged that the acceleration aging of Electric arc funace reduced slag is effective according to the immersion of CO₂ nano-bubble.