• Journal of the Korean GEO-environmental Society
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• v.13 no.5
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• pp.51-57
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• 2012

The purpose of study is to understand the possibility of biogrout of soil induced by bacteria. Microbial Calcium Carbonate Precipitation(MCP) has been analysed using the microorganism Bacillus Pasteurii. In order to understand the biogrout of soft ground treated with microbial calcium carbonate precipitation, four types of specimens(sterilization soil, non-sterilization soil, reaction solution and microorganism solution with pre-treatment mix and reaction solution and microorganism solution with post-treatment mix) were made. Scanning Electron Microscope(SEM), EDX and X-ray diffraction(XRD) analyses were performed on the soft ground specimens. On the basis of the preliminary results, it appears that microbial treatment methods using calcium carbonate precipitation may be possible to improve property of biogrout.

• Journal of Korea Foresty Energy
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• v.18 no.2
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• pp.62-69
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• 1999

Lignin in wood cell walls influeced the transformation of the cellulose crystal structure during mercerization. Samples of sound and decayed woods by white rot fungus of Quercus mongolica were treated with 20% aquous NaOH solution, followed by washing and drying, and delignified. The effect of delignification on cellulose structure was investigated by a series of an X-ray diffraction analysis and ultraviolet(UV) microscopy. Delignification of alkali-treated woods did not influence their cellulose crystal structures. It may be concluded that lignin prevents the swelling of wood cellulose during mercerization and restrain the intermingling of cellulose chains.

• Explosives and Blasting
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• v.28 no.2
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• pp.59-68
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• 2010

Building demolition and blasting work in urban areas has a possibility which has an effect on the structural stability of nearby structures. In this study, the compressive strength and chemical composition of decrepit concrete materials were estimated by Schmidt rebound test and XRD phase analysis. The damage index of the concrete materials was calculated by measured P-wave velocities. It was revealed that the constituents of the concrete materials affect on the compressive strength. The damage index decreases with increasing compressive strength and decreasing impact energy.

• Journal of the Korean Ceramic Society
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• v.38 no.4
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• pp.325-330
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• 2001

고상반응법으로 이론 밀도의 약 97%의 소결 밀도를 갖는 N $d_{1-x}$S $r_{x}$G $a_{1-x}$M $g_{x}$ $O_{3{\delta}}$(x=0, 0.03, 0.07, 0.1) 고체전해질을 제조하였다. X선 회절 분석 결과, x=0.03일 때의 X선 회절도는 순수한 NdGa $O_3$와 같았으나, x=0.07, 0.1일 때에는 불순물이 나타났다. 교류 복소임피던스는 4$50^{\circ}C$~90$0^{\circ}C$의 온도 범위에서 공기 중에서 측정하였으며, 각 조성에 대하여 상호 비교 분석하기 위하여 복소비저항 스펙트럼으로 변환하여 해석하였다. 전기전도도는 N $d_{0.93}$S $r_{0.07}$G $a_{0.93}$M $g_{0.07}$ $O_{0.97}$(x=0.07) 시편이 90$0^{\circ}C$에서 6$\times$$10^{-3}$ S$cm^{-1}$ /로 가장 우수하였으며, 활성화 에너지는 저온 영역에서는 1 eV, 고온 영역에서는 0.74 eV이었다.다.

• Journal of the Korean Society for Nondestructive Testing
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• v.22 no.5
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• pp.539-544
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• 2002

The purpose of this study is to examine the change of full width half maximum(FWHM) and residual stress during fatigue process in S45C Steel, by X-ray diffraction. For S45C Steel, the relationship between the change in fatigue damage of the specimen and the FWHM, and residual stress of X-ray diffraction profiles during the fatigue processes has been investigated. The FWHM decreases in the early period of fatigue cycle. The change of FWHM is associated with cyclic work hardening. The change of the FWHM is not significant in $10{\sim}20%$ of ratio of fatigue life. The residual stress is changed with fatigue cycle increasing during the fatigue pro process.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.2
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• pp.94-103
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• 1991

ZnO-$P_2O_5$ system glasses containing 45 to 60 mol% ZnO have been melted at$1200^{\circ}C$and crystallized through controlled heat treatment. The properties of the base glass and crystallized glass were examined with XRD. FTIR. density. thermal expansion, electric conductivity, hardness. The principal crystalline phase was identified as zinc metaphosphate [$Zn(PO_3)_2$ in crystallized glasses containing 45-55mol% ZnO and zinc pyrophosphate ($Zn_2P_2O_7$) in the sample of 60mol% ZnO with X - ray diffraction analysis. Thermal expansion coefficient and DC electrical conductivity were varied with direction of oriented crystalline in the samples containing 50-60mol% ZnO. This suggests the existance of the oriented crystalline.

• 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.

• Korean Journal of Materials Research
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• v.6 no.4
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• pp.436-445
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• 1996

비정질 실리콘박막의 고상결정화 특성에 대한 비정질 박막의 증착방법, 수소화 정도, 표면결정 활성화 에너지 변화 및 열처리 환경 영향을 X선 회절, EDAX, Raman 분광 분석으로 조사하였다. 저온(58$0^{\circ}C$)열처리 corning 시료에서 기판 barium(Ba), aluminum(AI) 성분의 막내 확산 임계열처리시간 및 확산에 기인 한 불안정 결정화 특성을 관찰하였다. 화학기상증착 석영 수소화 시료에서 hard damage 기계적 활성화 효과로 얻어진 조대결정립 결정화 특성을 X선 회절의 (111) 배향 상대강도 변화로 관찰 할 수 있었으며, 이는 활성화 효과에 의한 고상 결정화 시 핵생성과 성장속도변화로 다결정 실리콘의 전기적물성 향상 가능성을 보여주었다. Soft damage, bare 활성화 처리 수소화막의 결정화는 비정질 상의 혼재, 박막 응력등의 저품위 입계특성 및 미세결정립 성장 특성으로 관찰되었으나, 활성화 전처리에 의한 저온 및 고온(875$^{\circ}C$)단시간(30분) 결정화는 확인 되었다. 스퍼터링 비수소화 막의 결정화는 상변태 상태의 Raman 결정피크로 분석 되었으며, 결정화 거동에 선행막의 스퍼터링 및 비수소화 영향은 활성화효과에 관계없이 불완전 저품위 결정특성으로 확인되었다. AFM 표면형상은 3차원 island 성막특성을 보여주었고 표면거칠기정도는 높은 것으로 관찰되었다.

• Journal of Ocean Engineering and Technology
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• v.7 no.2
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• pp.103-113
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• 1993

X-ray diffraction analysis technique was used for the fatigue damage analysis and fatigue life prediction in Al 7075-T651 alloy. The tensile test, fatigue strength and fatigue crack propagation test with change of stress ratio were carried out. As a result, half-value breadth was increased with the plastic deformation in the specimen increasint at all test conditions. In particular, half-value breadth at the surface of the specimens fractured by fatigue was increased as stress intensity factor range and effective stress intensity factor range were increased. In addition, the good relationship between half-value breadty and diffraction pattern was shown.

• Journal of the Korean Wood Science and Technology
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• v.37 no.3
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• pp.208-215
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• 2009

As a fundamental study to develop absorbing materials on harmful volatile organic compounds (VOC) such as formaldehyde, structural and crystalline characteristics of MDF carbonized at different temperatures were examined by a scanning electron microscope and an X-ray diffraction method. Fibers in surface layer of MDFs showed more compressed morphology than those in middle layer of MDFs, but the porosity of MDFs increased with increasing the carbonized temperature. The wrinkle shape was frequently surfaces of cell walls was more severe than that at the lumina of cells. The shape of pits in the fibers of carbonized MDFs were hardly changed. The cell walls of MDFs carbonized at $400^{\circ}C$ and over showed an amorphous-like structure without cell layering. X-ray diffratograms from the MDFs carbonized at $400^{\circ}C$ showed a trace of crystalline cellulose. On the other hand, an amorphous diffraction pattern from carbons was obtained with the MDFs carbonized at $1,000^{\circ}C$.