• 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.

• 한국의류산업학회지
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• 제3권4호
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• pp.367-372
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• 2001

Five kinds of commercial ramie and hemp fabrics were treated with cellulase under different concentrations. Samples were mercerized before enzyme treatment to investigate the effect of mercerization on cellulase enzyme treatment. Physical characteristics(weight loss, tear strength retention, wrinkle recovery, drape stiffness, dyeability) of cellulase enzyme treated and untreated samples were measured and compared. X-ray diffractions were examined to verify if there were any changes in their crystallinity of enzyme treated fabrics. Weight loss, wrinkle recovery and degree of crystallinity increased as the concentration of cellulase enzyme increased. In the meanwhile, tear strength retention and drape stiffness and dyeability decreased. Enzyme activity was more effective on mercerized samples. Particularly, there was distinct tendency to increase weight loss and flexibility.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2008년도 춘계학술대회
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• pp.222-228
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• 2008

The chemical composition and thermal, crystal characterization of oak mushroom waste were investigated in comparison with those normal oak wood for utilization of cellulose from oak mushroom waste. The oak mushroom waste contained a higher percentage of ash, and hot water extractives than oak wood. This results indicated that the materials inside the body are easily decomposed during the oak mushroom cultivation. The lower percentage of holocellulose and a-cellulose of oak mushroom waste caused by fungal decomposition too. Whereas, the thermal decomposition behavior and crystallinity of oak mushroom waste was similar to that of normal oak wood, which indicated that the cellulose characterization of oak mushroom waste is resistant to fungal decomposition. In additionally, a degree of polymerization of oak mushroom waste must be investigate for examination of cellulose crystalline characterization, especially.

• 한국정밀공학회지
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• 제21권11호
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• pp.195-199
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• 2004

For the present study, the cryogenic ball milling process was applied to make Ibuprofen microsized. The cryogenic ball milling was performed at low temperature of about -18$0^{\circ}C$ for 6 hours. The particle size distribution was determined before and after the cryogenic process. X-ray diffraction (XRD) measurement was made to determine the effect of cryogenic process on the crystallinity of Ibuprofen. The results showed that the size of Ibuproffn was reduced about 10 times by the cryogenic process. The degree of crystallinity of Ibuproffn was slightly reduced by the cryogenic process.

• 펄프종이기술
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• 제45권3호
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• pp.59-68
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• 2013

The cotton contains various impurities such as protein, wax, pectins, coloring matter, even though cotton has been a major source of pure cellulose. The purification processes have been commonly applied to obtain the pure cellulose. However the excessive purification treatments could lead to the damage in the cellulose structure which could result in the degradation of cellulose and the limited application of cotton cellulose. In this study, the changes in cellulose structural properties such as crystallinity and DP(degree of polymerization) by the various conditions of the purification processes were investigated. The less toxic agents such as hydrogen peroxide and sodium silicate were applied for the purification treatment in this study. The increase in the process times, the temperature and the applied amount of chemical agents resulted in the more purified cellulose. The DP of cotton cellulose was increased at the first weak conditions by the reduction of small molecules such as pectin, wax, and so on. Especially the 2 % addition amount of $H_2O_2$ with $Na_2SiO_3$ resulted in the higher value in the DP and the brightness compared to the 1.5 % addition amount of $H_2O_2$. However, the 4 % addition amount of $H_2O_2$ with $Na_2SiO_3$ showed the decreased value because of excessive treatment. In case of the changes in the crystallinity (Gjk), the highest value of the crystallinity was obtained by the 2% addition amount of $H_2O_2$ on the cotton cellulose, which showed similar with the change in the DP.

• 폴리머
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• 제25권5호
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• pp.657-664
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• 2001

본 연구에서는 고분자 수지의 가교율 향상을 위하여 가교제를 첨가한 low density polyethylene (LDPE), linear low density polyethylene (LLDPE) 수지의 가교에 있어서 ${\gamma}$-선 조사의 효과를 조사하였다. LDPE와 LLDPE 시편들은 가교제와 혼합하여 13$0^{\circ}C$의 hot-press mold에서 sheet 형태의 준비하였다. ${\gamma}$-선은 질소분위기에서 50부터 150 kGy로 변화시키며 조사하였다. 이렇게 준비된 시편을 이용하여 방사선 조사선량, 가교제의 종류에 따른 가교율의 변화를 조사하였으며 가교에 따른 기계적 특성, 열안정성과 결정차도의 변화도 평가하였다. 그 견과 방사선 조사선량이 크고, 가교제가 첨가되면 가교율은 상승하였다. 그것과 비례하여 물리적 성질과 열적인 성질도 개선되었다. 그리고 방사선 조사에 의해서 순수한 수지의 겔화율이 증가하면 결정화도는 감소하였다.

• 한국의류산업학회지
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• 제21권3호
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• pp.356-362
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• 2019

This study investigated the substantivity of anionic dyes for cationic-modified new rayon (cocell) fabric treated with cationic agent (CA), 3-(Chloro-2-hydroxypropyl)-trimethylammonium chloride (CA). We also investigate the dyeability of cationic-modified new rayon fabric after dyeing with gallut. CA was converted in an aqueous solution of sodium hydroxide into epoxypropyl trimethylammonium chloride. Treating with this epoxy reagent modified the hydroxyl groups of the new rayon fabric into the trimethylammonium group through ether linkage. The introduction of new cationic sites into new rayon fabric by pretreating with cationic agent improved the substantivity of the Gallnut dye with the new rayon dyebath. The degree of the cationization of cationic-modified new rayon and cotton fabric was evaluated by nitrogen (N) content. This study extracted the colorant of gallnut with hot water at $90^{\circ}C$ and 120 min. Cationic-modified new rayon fabric dyed with extracted solution from gallnut according to concentration of gallnut, dyeing temperature, dyeing time and concentration of cationic agent. Dyeability (K/S) was obtained by CCM observation after dyeing with gallut solution. In addition, fastness to washing and light were also investigated. The degree of crystallinity of new rayon and cotton fabric were 42.15% and 54.94%, respectively. N (%) content of cationic-modified new rayon was higher than the cationic-modified cotton. Dyeability (K/S) increased significantly with the increasing concentration of CA and gallut.

• 한국가정과학회지
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• 제2권1호
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• pp.142-148
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• 1999

Tencel fabrics were treated with cellulase after mechanical prefibrillation treatment. SEM analysis was carried out to study morphological change of the treated fabric. The cellulase-treated Tencel fabrics were evaluated for weight loss and tensile strength. X-ray diffraction method, moisture regain, and K/S value were used to elucidate crystalline structural changes occurred by cellulase treatment. Degree of polymerization and copper number of the cellulase-treated fabrics were also measured to estimate effect of hydrolysis. SEM analysis indicated that with treatment of prefibrillation and cellulase, fibrils were produced and damage occurred deep into the fiber. Increases in concentration and time of cellulase treatment increased weight loss and decreased tensile strength retention of the treated fabrics. As cellulase hydrolysis progressed, degree of crystallinity, moisture regain and K/S value were not much changed. (Korean J Human Ecology 2(1) : 142∼148, 1999)

• Journal of the Korean Wood Science and Technology
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• 제36권1호
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• pp.12-20
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• 2008

국내에서 성장한 주요 침엽수 3종(소나무, 잣나무, 리기다소나무)의 수간 내 셀룰로오스 상대결정화도와 결정폭에 대한 수평방향 및 수직방향 변이를 X선 회절법에 의해 조사하였다. 각 수종의 상대결정화도 평균값은 소나무 60.6%, 잣나무 61.7%, 리기다소나무 49.4%로 리기다소나무가 가장 낮게 나타났다. 공시 수종의 상대결정화도는 약 10~15연륜까지 증가하다가 그 후 거의 일정한 값을 보여 주었고 만재부의 상대결정화도가 조재부의 상대결정화도보다 다소 높게 나타나는 경향이 있었다. 소나무 상대결정화도는 수관부보다 기부에서 다소 낮게 나타났으나 잣나무, 리기다소나무는 수고에 따른 차이를 거의 나타내지 않았다. 각 수종의 셀룰로오스 결정폭은 3수종 모두 2.8~3 nm 정도로 거의 차이가 없었고 수평방향 및 수직방향, 조만재 간에도 차이가 없었다. 따라서 상대결정화도와 결정폭 중 상대결정화도는 국내산 주요 침엽수재의 미성숙재와 성숙재를 구분하는 재질 지표의 하나로 이용이 가능할 것으로 생각되었다.

• 보존과학회지
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• 제37권6호
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• pp.648-658
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• 2021

본 연구에서는 증해제 종류(천연 잿물, Na₂CO₃)와 초지 시기(겨울, 여름)가 다른 한지를 선정하여 105℃의 가속열화 환경에서 나타나는 한지의 화학적 변화를 분석하고자 하였다. 백색도(brightness) 및 황색도(yellowness), pH를 측정하여 한지의 열화 정도를 확인하였으며, 적외선 분광분석(FT-IR)을 통해 열화가 진행됨에 따른 셀룰로오스 내 작용기의 변화 정도를 나타내었다. 이를 바탕으로 X선 회절분석(XRD)과 라만 분광분석을 실시하여 FT-IR에서 나타난 셀룰로오스 내 결정 및 비결정영역의 변화를 검증하였다. FT-IR 분석결과, 열화가 진행됨에 따라 셀룰로오스 내 비결정영역의 흡광도는 감소하는 반면 결정영역의 흡광도는 미미하게 증가하는 양상을 보였다. 결정영역의 증가는 XRD 분석 후 결정화도(Crystallinity Index, CI) 산출을 통해 열화 후 다소 증가함을 보여 같은 경향을 띠는 것을 확인할 수 있었다. 또한 라만 분광분석 결과, 열화 후 측정된 형광을 통해 초지 조건에 따른 셀룰로오스 내 비결정영역의 분해 정도를 확인하였다.