• 한국의류학회지
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• 제30권7호
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• pp.1025-1033
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• 2006

Kenaf bast can be obtained by decortication of Kenaf stem. Kenaf fibers are much more rough than cotton fiber because they include impurities as pectin, lignin and hemicellulose besides cellulose. The purpose of this research is to investigate the distribution of kenaf fiber length and diameter during the processes of removing impurities. To remove pectin, kenaf bast was retted chemically. A half of the retted kenaf fiber bundle were scoured and bleached. The other half one were treated with $NaClO_2$ solution to remove lignin, and were treated with sodium hydroxide solution to remove hemicellulose. Four kinds of specimens that were obtained for investigating physical characteristics. Length and diameter of 100 fibers on each specimen was measured. The tensile strength of 100 fiber bundles were measured. And also the color values of them were measured with spectrocolorimeter. The length of retted kenaf fiber was 16.97cm. Then it decreased to 11.43cm after bleaching. Kenaf fiber bundles could be finer by chemical processes that remove non-cellulosic materials. The thickness of retted fiber was $132{\mu}m$. And after undergoing the chemical processes to remove non-cellulosic materials, the thickness of kenaf fiber became finer as $73{\mu}m$. Tensile strength of the retted kenaf fiber bundles was 11.37Mpa. The retted kenaf fiber lost their strength as 22.6% by bleaching and as 18.3% by treatment for removing lignin. The retted kenaf fiber showed low whiteness as 56.48 of L*value. After bleaching, the kenaf fibers have creamy white color and their whiteness got 90.02 of L*value. After the treatment for removing hemicellulose, the kenaf fibers also have creamy white color and their whiteness got L* value of 79.02.

• Journal of Pharmaceutical Investigation
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• 제38권1호
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• pp.31-38
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• 2008

The objective of this work is to study transdermal delivery of levodopa using iontophoresis and evaluate various factors which affect the transdermal transport. Levodopa is unstable in aqueous solution, and, in order to establish a stable condition for levodopa for the duration of experiment, we investigated the stability of levodopa in aqueous solutions of different pHs with/without the addition of dextrose or the application of current. Using stable aqueous solution, we have studied the effect of pH, polarity and penetration enhancer (ethanol) on transdermal flux and compared the results. We also investigated the iontophoretic flux from hydroxypropyl cellulose (HPC) hydrogel. In vitro flux study was performed at $33^{\circ}C$, using side-by-side diffusion cell. Full thickness hairless mouse skin and rat skin were used for this work. Current densities applied were 0.4 or $0.6mA/cm^2$ and current was off after 6 hour application. Stability study showed that levodopa solution with a pH 2.5 or 4.5 maintained the initial concentration of levodopa for 24 hours with the addition of 5% dextrose. However, at pH 9.5, levodopa was unstable and 30 to 40% of levodopa degraded within 24 hours, even with the addition of 5% dextrose. Hydrogel swollen with dextrose added levodopa solution maintained about 97% of the initial concentration of levodopa for 13 days, when stored in $4^{\circ}C$. The application of current did not affect the stability of levodopa in hydrogel. Flux study from levodopa solution with pH 2.5 showed that cathodal delivery of levodopa was higher than passive or anodal delivery. When the pH of the donor solution was 4.5, anodal delivery of levodopa was higher than passive or cathodal delivery. These results seem to indicate that electroosmosis plays more dominant role than electrorepulsion in the flux of levodopa at pH 2.5, and the reverse situation applies for pH 4.5. The passive flux was unexpectedly high for the ionized levodopa. Similar to the results from aqueous solution, cumulative amount of levodopa transported trom HPC hydrogel by cathodal delivery was significantly higher than passive or anodal delivery. The treatment of 70% ethanol cotton ball by scrubbing increased passive, anodal and cathodal flux, with the largest increase for anodal flux. These results indicate that iontophoretic delivery of zwitterion such as levodopa is much complicated than that can be expected from small ionic molecules with single charge. The results also indicate that the balance between electroosmosis and electrorepulsion plays a very important role in the transport through skin.

• 보존과학회지
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• 제29권2호
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• pp.161-170
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• 2013

본 연구의 목적은 실질적인 출토복식의 보수를 통해서 보수방법의 합리적인 방안을 모색하는데 있다. 출토복식의 경우 유기물이라는 특징으로 인해 출토되는 순간 이미 위약한 상태이므로 출토복식에 대한 상태를 철저히 조사한 후 가능한 물리적 힘을 가하지 않는 방법으로 최소한의 보수만을 진행하였다. 그리고 다음과 같은 과정으로 보수하였다. 보수는 출토복식의 상태에 따라 보수 가능한 것을 분류하여 출토복식 직물의 상태를 고려하여 최대한 안정하게 적용시켰다. 보수용 실의 경우는 강도가 약한 정련한 얇은 주아사의 실을 뽑아서 사용하거나 광열화시킨 명주실을 사용하였다. 보수용 직물은 직물의 종류에 따라 셀룰로오스 계 직물은 면직물을 견직물은 주아사나 명주를 정련하여 사용하였으며 일부는 비슷한 색을 내기위해 오리나무 염색과 감 염색을 하였고 방충 방균 처리를 위해 정향으로 염색한 천을 사용하여 보수하였다. 보수의 방법은 손상형태 및 복식의 구성양식에 따라 구분하여 실시하였다. 보수의 바느질법은 시침질, 홈질, 박음질, 공그르기, 감침질의 방법을 사용하여 훼손 부위와 상태에 적합한 바느질법을 선택하였다.

• 한국가금학회지
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• 제12권1호
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• pp.25-30
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• 1985

가금에서의 영양소리용성에 미치는 볏짚구성분의 영향을 고찰하기 위하여 증류수 혹은 0.25N NaClO$_2$ 800$m\ell$당 볏짚 100g의 비율로 침지하여 135$^{\circ}C$ 3.2kg/$\textrm{cm}^2$ 압력밑에서 각각 30, 60 및 120분 autoclave를 이용하여 가열하고 세척 건조(증류수 혹은 NaClO$_2$-30, 60 및 120-볏짚) NDF, ADF 및 리그닌량을 조사하였다. 갓부화한 단관백색 레그흔 숫병아리에 10일간 시판 병아리 사료를 급여하고 계속해서 8일간 밀기울(기초), 섬유소(선분), 무처리볏짚, 증류수-30-볏짚 및 NaClO$_2$-30-볏짚이 각각 17.0% 함유된 실험사료를 급여했다. 증류수-30, 60 및 120-볏짚의 건물손실율은 각각 9.7, 12.1 및 13.3%였으나, NaClO$_2$-30, 60 및 120-볏짚에서는 각각 8.8, 18.7 및 19.4%로, NaClO$_2$-60 및 120-볏짚에서는 증류수볏짚의 1.5배가 되었다. 증류수 및 NaClO$_2$ 볏짚의 건물손실은 주로 무처리볏짚의 세포내용물과 헤미셀루로스의 용출에 기인하는 것이었다. 증류수-30-볏짚을 급여한 병아리는 무처리 혹은 NaClO$_2$-30-볏짚을 급여한것에 비해서 증체량이 높고 사료요구량이 낮았다. 질소밸런스 및 축적율은 증류수-30-볏짚을 급여한것에서 무처리 및 NaClO$_2$-30-볏짚을 급여한것에 비해서 높았고, 조지방소화율은 높아지는 경향이 있었다. 무처리, 증류수-30 및 NaClO$_2$-30-볏짚을 급여한 병아리의 MEn/GE는 각각 71.9, 72.9 및 70.4%였으며, 대사체중(kg 0.75)당 MEn섭취량은 각각 307.3, 296.2 및 291.4 KCal가 되었다. 이때 kg 0.75당 1일 단백질축적량은 각각 1.647, 1.969 및 1.560g이었다. 한편 증류수-30-볏짚을 급여한 병아리의 단백질 1g 축적에 상당하는 MEn는 30.56Kcal로써 무처리 및 NaClO$_2$-30-볏짚을 급여한것의 36.90 및 37.58Kcal보다 낮았다. 따라서 무처리볏짚에는 에너지 이용성 혹은 단백질축적에 영향을 미치는 물질 혹은 성질이 존재하며, 이것은 볏짚을 끓임으로써 제거된다는 것을 시모고 있다.