• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.227-227
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• 2003

흑연(graphite), 석탄(coal), 숯(char), soot(검댕이) 등의 탄소로 이루어진 재료들은 비정질부터 완전한 흑연결정까지 다양한 구조를 나타낸다. 이러한 탄소재료의 구조의 출발물질 뿐 아니라 열처리에 따라 강한 영향을 받는다 이러한 구조는 여러 구조인자에 의해 특성화되는데, 구조인자로는 층간거리 d, 결정립 크기 Lc 그리고 결정립 직경 La이다. 이런 구조 인자의 지식은 흑연화, 탄소화, 가스화 등과 같은 다양한 공정을 이해하는데 매우 중요하다. 많은 연구자들은 XRD, Raman 분광, 고분해능 TEM 등과 같은 여러 기술을 통하여 이러한 구조인자에 대한 해석을 시도하였다. 그 중 XRD는 정량적 분석에 있어서 가장 많이 이용되는 기술이다. XRD 회절피크의 위치로부터 층간거리 d를 구할 수 있으며, 결정립 크기 Lc 및 결정립 직경 La는 피크의 line 퍼짐(반가폭)으로 직접 구할 수 있다. 한편 섬유상 흡착제로 이용되는 등방성 탄소섬유는 이산화탄소 또는 수증기에 의해 쉽게 활성화되어 최고 약 2,500 $m^2$/g의 고 비 표면적을 얻을 수 있다. 이렇게 활성화 후 고 비표면적을 나타내는 이유는 좁은 분포를 나타내는 미세기공의 기공구조 때문에 발생하는 것으로 알려져 있다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.189-190
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• 2018

This study produced Portland limestone cement at the rate of limestone substitution by grinding limestone and clinker together, and it conducted an XRD analysis to determine the sign language response structure as a basic study on Portland Limestone Cement. As a result of the XRD analysis, the higher the substitution rate of limestone, the more likely it is that the detection rate of ettringite is decreased. Additionally, we could see that the production volume of Mono-carbonate was increasing.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.11a
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• pp.213-216
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• 2001

극자외선영역의 빛에대한 Mo/Si 반사형 다층 박막 미러를 스퍼터링 시스템으로 증착하여, 특성을 평가한 결과 3mTorr의 낮은 공정 압력에서 최적의 구조인자를 가진 다층 박막을 증착할 수 있었다. TEM, low angle XRD peak, 반사도 그래프로부터 다층 박막의 구조인자를 분석하였으며, 특히 low angle XRD peak로부터 다층박막의 d-spacing, 층간 두께 uniformity에 대한 정보 및 광학적 정보를 간접적으로 분석할 수 있었다. 최대 반사도는 12.7nm 파장에서 약 53%였으며, low angle XRD에서 추출한 d-spacing 값이 TEM 이미지에서 측정한 값보다 더 정확한 값을 얻을 수 있었다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.11a
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• pp.196-197
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• 2015

ZnSe의 전기화학적 거동은 각각 다른 pH를 갖는 전해질에서의 linear sweep voltammogram 분석에 의해 체계적으로 고찰되었다. 제어된 조성을 갖는 칼코지나이드 ZnSe 박막이 complexing agent의 역할을 하는 citrate를 포함한 알카리 용액에서 전해 증착되었다. 다른 pH의 전해질에서 증착된 ZnSe 박막의 형상을 분석하고, 추가적으로 다른 pH의 전해질 및 어닐링 온도 변화에 따른 ZnSe 박막의 XRD분석이 이루어졌다.

• Journal of the Korean Wood Science and Technology
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• v.35 no.1
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• pp.36-43
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• 2007

Elemental analysis, SEM-EDX, X-ray diffraction (XRD) and IR analysis were adopted to examine the quality of charred woods excavated from the underground of the Daewoongjeon Hall of Youngguksa Temple, Youngdong-gun, Chungbuk, Korea. A large amount of calcium was detected in SEM-EDX analysis. The analyses of chemical elements suggested that completely charred wood was carbonized at about $500^{\circ}C$. The XRD results indicated the destruction of cellulose crystalline region. The IR analysis exhibited that thermal degradation of wood component was different depending upon the carbonization temperature. It can be suggested from the results that PEG with different molecular weights should be used for the conservation of excavated charred woods.

• Fire Science and Engineering
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• v.28 no.5
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• pp.58-63
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• 2014

Fire-resistance paints are supposed to become intumescent and diminish heat transfer along the steel frames in case of a fire. If unsatisfactory fire-resistance paints which do not satisfy their standard specification are used, it may result in a severe disaster. Because satisfactory fire-resistance paints are hardly discriminated from the unsatisfactory ones by a simple visual inspection, more reliable and convenient onsite evaluation methods are necessary. Here we report the preliminary study result on the fire safety testing method for fire-resistance paints using an X-ray analysis method. It was found that the existence and quantity of effective constituents in fire-resistance paints can be detected by the X-ray analysis method. X-ray fluorescence (XRF) analyses showed that P and Cl elements are much more enriched in fire-resistance paints, compared to normal paints. X-ray diffraction (XRD) analyses showed that ammonium polyphosphate is present as the main crystalline material in fire-resistance paints, but absent in normal paints. The X-ray analysis method is expected to be used for the onsite inspection of fire-resistance paints with the upcoming availability of portable XRF and XRD instruments.

• Cement
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• s.126
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• pp.65-71
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• 1992

• The Korean Journal of Malacology
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• v.31 no.4
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• pp.279-283
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• 2015

This study investigated spectroscopic characteristics of shell crystals of eight marine bivalve species using X-ray diffraction (XRD) analysis; moreover, the Family level relatedness of shellfish was investigated. In XRD analysis, the shells of Ruditapes philippinarum, Meretrix lusoria, Anadara granosa, and Fulvia mutica were found to have orthorhombic aragonite $CaCO_3$ crystals, while shells of Patinopecten yessoensis and Crassostrea gigas had trigonal-rhombohedral calcite crystals. The shells of Mytilus coruscus and Atrina pectinata were determined to have a mixture of aragonite and calcite crystals. XRD information revealed the Family level-specific characteristics of shellfish; the results agreed with the current taxonomic system. In conclusion, spectroscopic characteristics of shell crystals indicated Family-level characteristics of shellfish and suggested a more intense species-level investigation; this technology may be useful in identifying shellfish species using small quantities of shells.

• Journal of the Microelectronics and Packaging Society
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• v.9 no.2
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• pp.1-9
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• 2002

The intermetallic formation between Sn-Ag-(Cu) solders and metal pads in a real BGA package was characterized using SEM, EDS, and XRD. The intermetallic phase formed in the interface between Sn-Ag-Cu and Au/Ni/Cu pad is likely to be ternary compound of $(Cu,Ni)_6Sn_5$ from EDS analysis High concentration of Cu was observed in the solder/Ni interface. XRD analysis confirmed that $\eta -Cu_6 Sn_5$ type was intermetallic phase formed in the interface between Cu containing solders and Ni substrates and $Ni_3$Sn_4$ intermetallic was formed in the Sn-Ag solder/Ni interface. The thickness of intermetallic phase increased with the reflow times and Cu concentration in solder.

• Journal of the Korean Ceramic Society
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• v.34 no.2
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• pp.209-215
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• 1997

Aluminum nitride(AIN) thin films were deposited by reactive single ion beam sputtering using N2 or NH3 as reactive gas. The structural, compositional and optical properties of AIN thin films were characterized by XRD, GAXRD, TEM, SEM, XPS UV/VIS spectrophotometer, and FT-IR. All the deposited AIN thin films were amorphous by the analysis fo XRD and GAXRD. However, TEM analysis showed that AIN nano-crystallites were uniformly distributed in the films. The presence of Al-N bonds were also confirmed by FT-IR and XPS analyses. The optical bandgap of AIN films increased up to 6.2 eV and the transmittance was a-bout 100% in visible range with approaching the stoichimetric composition. Irrespective of using N2 or NH3 as reactive gas, the deposited AIN thin films had very smooth surface morphologies. Their refractive index ranged from 1.6 to 1.7.