• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 C
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• pp.1019-1021
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• 1995

Light induced degradation of hydrogenated amorphous silicon(a-Si:H) are related to the number of weak dangling bonds which are thought to be responsible for the Staebler-Wronski effects, and caused the many photoelectric problems in applications of thin film transistors and solar cell, etc. In this paper, we deposited fluorinated amorphous silicon films(a-Si:H;F) with $SiH_4$ and $SiF_4$ gas mixture and investigated the effects of fluorine atoms on the evoluations of the crystallinity and improvements of light instability. We have found that micro-crystallinity produced in a-SI:H;F films and marked maximum value of 22% at the flow rate of $SiH_4:SiF_4$=2:10 sccm by UV spectrophotometer measurement, while n-Si:H film deposited with only $SiH_4$ gas showed no crystallinity. Light-induced degradation property of a-Si:H;F films is also improved which is mainly due to the etching effects of fluorine atoms on the weak Si-Si bonds and unstable hydrogen bonds. It is considered that involving fluorine atoms in a-Si:H films may contribute to the suppression of light-induced degradation and evolution of micro-crystallinity.

• Carbon letters
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• 제10권4호
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• pp.300-304
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• 2009

Thermal emissivity of nuclear graphite was measured with its oxidation degree. Commercial nuclear graphites (IG-110, PECA, IG-430, and NBG-18) have been used as samples. Concave on graphites surface increased as its oxidation degree increased, and R value (Id/Ig) of the graphites decreased as the oxidation degree increased. The thermal emissivity increased depending on the decrease of the R (Id/Ig) value through Raman spectroscopy analysis. It was determined that the thermal emissivity was influenced by the crystallinity of the nuclear graphite.

• 한국잠사곤충학회지
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• 제35권1호
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• pp.52-59
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• 1993

비누 정련 견사와 효소 정련 견사의 결정 구조는 정련 구조 중 처리온도의 차이에 의하여 효소 정련 견사의 결정성이 비누 견사의 결정성 보다 높다고 전보(김·남, 1992)에서 보고하였는데 이와같은 정련 견사의 결정성의 차이가 정련 견사를 열처리를 하였을 때 어떻게 변화하는지를 밝히기 위하여 두가지 방법으로 정련한 견사에 대하여 습열 처리와 동결 처리한 후 특성을 분석한 결과는 다음과 같다. 1. 정련 견사를 습열 처리한 경우 강력과 신도는 모두 저하되었으며 비누 정련 견사는 습열 처리온도의 상승과 함께 열 분해 온도도 고온측으로 이동하고 IR crystallinity도 증가하였으나 효소 정련 견사는 습열 처리에 의하여 열 분해 온도와 IR crystallinity의 큰 변화가 없었다. 이와 같은 결정 구조의 차이는 비누 정련 견사는 습열 처리로 재배향 결정화가 일어나 결정화도는 증가되었으나 효소 정련 견사는 습열 처리에 의한 재배향 결정화보다 습열 처리에 의하여 팽윤되어 수축하는 과정에서 배향성이 저하되기 때문에 결정성은 더 이상 증가되지 않은 것으로 추측된다. 2. 정련 견사를 동결 처리하였을 때 강력과 신도는 약간씩 감소하는 경향이었으나 열 분해 온도와 IR crystallinity는 비누 정련 견사와 효소 정련 견사 모두 큰 변화가 없었다.

• Fibers and Polymers
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• 제6권3호
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• pp.206-218
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• 2005

Structural studies of series of 'as spun' and drawn PEEK fibers have been carried out using X-ray diffraction and optical microscopy techniques. The analysis of results suggest that fibers produced at a constant draw ratio with increasing draw temperatures show enhanced orientation and crystalline behaviour. The resolved equatorial and meridional traces provide additional structural parameters in terms of crystallinity, crystallite size, and crystallite thickness. It is concluded that drawing at a temperature below $T_g(i.e.,\;144^{\circ}C)$ results in poorly oriented non-crystalline materials, whereas drawing above $T_g$ results in highly oriented semi crystalline materials. Additional drawing proved to increase the overall orientation with slight improvements in lateral order of the chain molecules. Quantitative analysis revealed that the crystallite size increases with increasing drawing temperature. The results also revealed the increased crystallite size upon additional drawing. Crystalline orientation parameter, $_c$, suggests almost perfect orientation. In all cases, the amorphous orientation is found to be lower than the overall orientation parameter obtained from the optical birefringence. As a result of additional drawing, crystalline orientation was found to increase slightly but the increase in the orientation of non-crystalline material was found to be substantial. An average crystalline density was determined from the orthorhombic unit cell dimensions. It was found to vary as a result of processing conditions. It was also found that the value of the maximum birefringence shows heavy dependence on the chain conformation.

• 보존과학연구
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• 통권35호
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• pp.87-98
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• 2014

뼈의 보존 상태를 화학적으로 평가하기 위하여 조선시대 인골 10점을 대상으로 감쇠전반사법을 활용한 적외선 분광분석(FTIR-ATR)을 실시하였다. FTIR-ATR 스펙트럼을 통해 결정화 지수(crystallinity index; CI), 탄산염간의 비(C/C), 탄산염과 인산염의 비(C/P)를 계산한 결과 CI는 $4.25{\pm}0.78$, C/C는 $0.91{\pm}0.04$, C/P 는 $0.19{\pm}0.06$으로 확인되었다. 화학적 평가 결과 조직학 지수가 높을수록 CI와 C/P 값이 증가하며, C/C는 감소하는 것을 확인하였다. 반면 뼈에서 추출한 DNA 분석 가능 여부는 C/C가 낮고 C/P가 높을수록 분석이 가능 하였다. 이를 통해 FTIR을 이용한 화학적 평가와 조직 분석 결과가 출토 인골의 보존 상태를 종합적으로 파악하기 위한 기준으로 적용이 가능할 것으로 판단된다.

• 펄프종이기술
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• 제47권6호
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• pp.57-65
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• 2015

Microfibrillated cellulose (MFC) or Nanofibrillated cellulose (NFC) has been used to reduce the use of raw pulp and to improve paper strength. The problem of MFC preparation is high manufacturing cost. In this study, it was carried out to prepare MFC after enzyme beating and estimated properties of MFC. Endo-D was the best beating efficiency among three type of endo-glucanase. As the grinder pass number increased, the viscosity and the fines of MFC suspension increased while the crystallinity and the porosity of MFC sheet decreased. Also enzyme beating MFC was higher value in the crystallinity and lower value in the viscosity than non-enzyme MFC. In addition, the aspect ratio of MFC was the highest at 5 pass. MFC addition improved the handsheet strength and the air permeability but worsened the drainage.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.1084-1087
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• 2001

The (Sr$\sub$0.85/Ca$\sub$0.15/)TiO$_3$(SCT) thin films are deposited on Pt-coated electrode(Pt/TiN/SiO$_2$/Si) using RF sputtering method. The crystallinity of SCT thin films is increased with increase of substrate temperature in the temperature range of 100[$^{\circ}C$]∼500[$^{\circ}C$]. Also, the crystallinity of SCT thin films are obtained at the substrate temperature above 400[$^{\circ}C$]. SCT thin films had (111) preferred orientation. The dielectric constant changes almost linearly in temperature ranges of-80∼+90[$^{\circ}C$]. The temperature properties of the dielectric loss have a stable value within 0.1. SCT thin films used in this study show the phenomena of dielectric relaxation with the increase of frequency, and the relaxation frequency is observed above 200[kHz].

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 춘계학술대회 논문집
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• pp.7-7
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• 2010

The SBN thin films were deposited at substrate temperature of 300[$^{\circ}C$] on Pt-coated electrode (Pt/Ti/$SiO_2$/Si(100)) using RF sputtering method. The grain and crystallinity of SBN thin films were increased with the increase of annealing temperature. The dielectric constant(150) of SBN thin film was obtained by annealing temperature above 750[$^{\circ}C$]. The frequency dependence of dielectric loss showed a value within 0.03 in frequency ranges of 1~1000[kHz].

• 한국염색가공학회지
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• 제21권4호
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• pp.63-67
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• 2009

m-Aramid dissolved in N,N-dimethylacetamide (DMAc), were coagulated in different coagulants such as water, methanol, ethanol, propanol and butanol. Various concentrations and temperatures of the coagulants were also used to evaluate dyeing properties of coagulated m-aramid films. Field emission scanning electron microscopy (FE-SEM) was employed to investigate the surface morphology of m-aramid films. Wide angle X-ray diffraction (WAXD) was conducted in order to measure crystallinity change of mcaramid fibers and films. WAXD patterns showed that crystallinity of m-aramid fibers was reduced after film formation. In addition, color depth (K/S value) was measured and the results revealed that the film coagulated in water possessed fairly enhanced color depth.

• 한국분말재료학회지
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• 제15권6호
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• pp.489-495
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• 2008

Colored tantalum oxy-nitride (TaON) and tantalum nitride ($Ta_{3}N_{5}$) were synthesized by ammonolysis. Oxygen deficient tantalum oxides ($TaO_{1.7}$) were produced by a titration process, using a tantalum chloride ($TaCl_5$) precursor. The stirring speed and the amount of $NH_{4}OH$ were important factors for controling the crystallinity of tantalum oxides. The high crystallinity of tantalum oxides improved the degree of nitridation which was related to the color value. Synthesized powders were characterized by XRD, SEM, TEM and Colorimeter.