• 펄프종이기술
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• 제34권4호
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• pp.30-36
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• 2002

This research was conducted to investigate the feasibility of using deinked pulp of white ledger(DIP) for the manufacture of high quality premium tissue. The three types of tissues were prepared using the softener treated bleached DIP, softener treated mixed pulp of unbleached DIP and virgin pulp, and untreated mixed pulp of bleached DIP and virgin pulp, respectively, and their tensile index. softness, and brightness were measured and compared. The bulk and surface softness increased only slightly by the addition of softener(0.2% mineral oil) into the bleached DIP. The tensile index was decreased by 15∼30%, and the brightness was the range of 86% to 87% ISO. The softener(0.2∼0.8% mineral oil or dialkyl imidazoline) treatment of mixed pulp of unbleached DIP and virgin pulp Improved the bulk and surface of tissue considerably. However, the brightness was low as 85% ISO or below. Although the softness of the tissue made from bleached DIP blended with virgin pulp was the lowest among three types of tissues evaluated, its tensile index was the highest and brightness was 87∼88% ISO. Based on the results, it may be predicted that the bleached DIP blended with virgin pulp is the best raw material for the manufacture of high quality premium tissue if softener treatment is applied to mixed pulp, because the softness can be improved by the addition of softener. In general, the softness of tissue was improved with the increase in the amount of softener: However, the tensile index inversely proportional to the amount of softener added. Dialkyl imidazoline was more effective than mineral oil with respect to the improvement in softness, even though the loss in tensile index was severe with the treatment of dialkyl imidazoline.

• 한국가구학회지
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• 제22권1호
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• pp.63-71
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• 2011

Hanji has known for its high qualities for more than thousand years. Hanji is stronger, and has better durability, air permeability, flexibility, thermal insulation, soundproofs and UV absorbability. Therefore, developing industrial interior finishing materials using Hanji is replaced with the PVC (Poly-Vinyl Chloride) materials instead, it will be a new environment-friendly material and positively represents Korean brand marketing. The industrial inter-construction material is discomposed by heat or light because of material characteristics. As a result, it emits a lot of noxious substances. Hanji is essentially a neutral paper since it does not rely on any acidic chemicals of artificial bleaching methods. Hanji is also known as the living paper because of its close relation to nature. Therefore, I would like to suggest that Hanji made from alternative material as a chicken fiber. It will be a non-polluting interior finishing materials by making use of Hanji to a taste of Korean culture in the green industry around the world. Rather than PVC used commonly in construction material, kitchen and office furniture, interior materials in the subway, trains, or other vessels, credit cards, and ID cards, I created an interior construction material by using patented Hanji. This will be increased the value of usefulness in the environment-friendly green industry instead of PVC.

• Restorative Dentistry and Endodontics
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• 제35권1호
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• pp.20-23
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• 2010

마우스가드는 19세기 복싱선수들의 구강내 열상과 연조직의 외상을 막기 위해 사용되었다. 최근에는 치과영역에서 다양하게 사용되고 있으며, 운동 보호 장치, 미백용 장치물, 교정용 유지 장치, 수술용 가이드 장치, 턱관절 안정 장치물 등에 쓰이고 있다. 습관적인 이 악물기에 의한 반복적인 5급 수복물의 탈락은 우선 이 악물기에 의한 스트레스를 조절한 후 수복이 이루어져야 한다. 마우스가드는 이 악물기에 의한 스트레스를 조절하는 장치물로 사용할 수 있다. 본 증례에서는 마우스가드로 치아에 가해지는 스트레스는 감소시키는 것에 대해 논의 할 것이다. 마우스가드를 사용함으로써 반복적인 탈락을 나타내는 5급 수복물의 유지에 단기적으로 만족스러운 결과를 얻을 수 있었다. 만약 환자 및 치과의사가 이 악물기로 반복적인 탈락을 나타내는 수복물로 고생하고 있다면, 마우스가드의 보조적인 사용이 치경부 수복물의 유지에 도움을 줄 수 있을 것이다.

• Advances in Traditional Medicine
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• 제8권3호
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• pp.266-278
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• 2008

Erythrina stricta, a deciduous tree widely used traditionally in indigenous system of medicine for various ailments such as rheumatism, fever, leprosy, epilepsy etc. The leaves of Erythrina stricta was extracted with ethanol (70%) and used for the evaluation of various in vitro antioxidant assays which includes H - donor activity, nitric oxide scavenging, superoxide anion scavenging, reducing ability, hydroxyl radical, hydrogen peroxide scavenging, total phenolic content, total flavonoid content, total antioxidant activity by thiocyanate and phosphomolybdenum method, metal chelating, $\beta$-carotene bleaching, total peroxy radical assays. The pro-oxidant activity was measured using bleomycin-dependent DNA damage. Ex vivo models like lipid peroxidation and erythrocyte haemolysis were also used to study the antioxidant property of the extract. The various antioxidant activities were compared with suitable standard antioxidants such as ascorbic acid, butylated hydroxyl toluene, $\alpha$-tocopherol, curcumin, quercetin and Trolox. The generation of free radicals viz. $O_2^{{\cdot}-}$, $OH^{\cdot}$, $H_2O_2$, $NO^{\cdot}$ and peroxyl radicals were effectively scavenged by the ethanolic extract of Erythrina stricta. In all the methods, the extract offered strong antioxidant activity in a concentration dependent manner. The total phenolic content, flavonoid content and total antioxidant activity in Erythrina stricta were determined as microgram (g) pyrocatechol, quercetin and $\alpha$-tocopherol equivalent/mg respectively. The extract did not exhibit any prooxidant activity when compared with ascorbic acid. The results obtained in the present study clearly indicates that Erythrina stricta scavenges free radicals and reduces lipid peroxidation, ameliorating the damage imposed by oxidative stress in different disease conditions and serve as a potential source of natural antioxidant.

• 한국의류학회지
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• 제30권12호
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• pp.1708-1713
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• 2006

모섬유에 높은 염착성을 가진 호두외피의 주색소인 주글론을 모발염색에 적용 가능성을 알아보기 위해 주글론의 모발에 대한 염색성을 조사하였다. 모발염색을 하기 위해서 먼저 시중 헤어전문점에서 사용하는 방법으로 모발을 표백하였다. 모발염색의 특성상 염색시간을 10-20분으로 섬유염색보다 훨씬 짧게 설정하였으며 염착성, 인장강도, 전자현미경 분석을 하였다. 염색시간이 증가함에 따라 염착성은 증가하는 경향을 보였으며 인장강도는 떨어져 모발 손상이 일어난 것을 알 수 있었다. 모발손상은 전자 현미경 사진으로 확인 되었다. 주글론 염색에 의해 모발에 YR 계열의 색상을 낼 수 있었다. 동시매 염 방법으로 철매염제를 사용한 결과 염착성 증진은 크지 않았으나, YR 계열 내에서 더 진한 색상을 얻을 수 있었다. 천연 모발염색에 주글론을 사용할 수 있을 것으로 사료되며, 염색조건에 따라 다양한 갈색계 열 색상을 부여할 수 있다.

• 한국염색가공학회지
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• 제27권2호
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• pp.149-154
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• 2015

To investigate the biodegradation of the cellulose powder(CP) derived from Styela clava tunics(SCT), some physico-chemical properties and biodegradability of SCT-CP were measured after the incubation for 45 days. The particles size of SCT-CP prepared with washing, bleaching, drying, and grinding processes was $150-400{\mu}m$ although most of particles (70%) was more than $400{\mu}m$. The cellulose structures of SCT-CP detected using the X-ray diffraction and DSC analysis was very similar with that of wood pulp powder(WP-CP). The glass transition temperature was not detected in both samples. Furthermore, more than 90% of the SCT-CP was degraded, whereas only over 70% of the WP-CP was degraded after the incubation for 45 days. Therefore, these results suggest the possibility that SCT-CP is particularly applicable to prepare medical fiber and film for disease treatment.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2003년도 춘계학술대회
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• pp.150-151
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• 2003

Benzoyl peroxide is a high production volume chemical, which was produced about 1,375 tons/year in Korea as of 2001 survey. Most of them are used as initiators in polymerization, catalysts in the plastics industry, bleaching agents for flour and medication for acne vulgaris. The substance is one of the sever chemicals of which human and environmental risks are being assessed by National Institute of Environmental Research under the frame of OECD SIDS Program. It has a melting point of 104-106 $^{\circ}C$ and has solubility of 9.1 mg/1 in water at 25 $^{\circ}C$. The substance was readily biodegradable (83 % after 21days) and had toxic effects to aquatic organisms. The range of 72 hr-EbC50 (biomass) for algae was 0.07-0.44 mg/1 and 48 hr-EC50 for daphnia was 0.07-2.91 mg/1. The LC50 of acute toxicity to fish was 0.24-2.0 mg/1. Although the toxic effects of benzoyl peroxide to aquatic organisms were investigated, environmental monitoring data were not studied. In this study, distribution of the chemical among multimedia environment was estimated using EQC model based on the physical-chemical properties to evaluate the risk of benzoyl peroxide in environment. In level I, II calculation the chemical was distributed to soil (68.3 %) and water (28.7 %). In level III calculation it was primarily distributed to soil (99.9 %) and overall residence time of 3.4 years was estimated. Benzoyl peroxide could be persistent in environment.

• Journal of Microbiology and Biotechnology
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• 제25권9호
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• pp.1476-1484
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• 2015

Three endoxylanase-encoding genes from the moderately themophilic chemoorganotrophic bacterium Melioribacter roseus were cloned and expressed in Escherichia coli. Genes xyl2091 (Mros_2091) and xyl2495 (Mros_2495) encode GH10 family hydrolases, whereas xyl2090 (Mros_2090) represents the GH30 family. In addition to catalytic domains, Xyl2090 and Xyl2091 contain carbohydrate-binding modules that could facilitate their binding to xylans and Por sorting domains associated with the sorting of proteins from the periplasm to the outer membrane, where they are covalently attached. Recombinant endoxylanase Xyl2495 exhibited a high specific activity of 1,920 U/mg on birchwood xylan at 40℃. It is active at low temperatures, exhibiting more than 30% of the maximal activity even at 0℃. Endoxylanases Xyl2090 and Xyl2091 have lower specific activities but higher temperature optima at 80℃ and 65℃, respectively. Analysis of xylan hydrolysis products revealed that Xyl2090 generates xylo-oligosaccharides longer than xylopentaose. Xylose and xylobiose are the major products of xylan hydrolysis by the recombinant Xyl2091 and Xyl2495. No activity against cellulose was observed for all enzymes. The presence of three xylanases ensures efficient xylan hydrolysis by M. roseus. The highly processive "free" endoxylanase Xyl2495 could hydrolyze xylan under moderate temperatures. Xylan hydrolysis at elevated temperatures could be accomplished by concerted action of two cell-bound xylanases; Xyl2090 that probably degrades xylans to long xylo-oligosaccharides, and Xyl2091 hydrolyzing them to xylose and xylobiose. The new endoxylanases could be useful for saccharification of lignocellulosic biomass in biofuels production, bleaching of paper pulp, and obtaining low molecular weight xylooligosaccharides.

• 보존과학회지
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• 제23권
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• pp.39-51
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• 2008

죽지는 최근 몇 십 년 간의 양지(洋紙)의 보급과 더불어 중국의 죽지 산지(産地)에는 생산성 만을 추구해 약품 사용이 극히 보편적인 현상이 되었다. 이러한 영향 때문에 지류 문화재의 보수지(補修紙) 문제가 심각한 문제로 제기되고 있다. 죽지를 염색하거나 색료를 도포하는 과정에 있어 생성되는 심한 얼룩이나 반점은 지류 문화재의 재현 연구에 큰 장애가 되고 있음은 주지의 사실이기도 하다. 이 번 죽지 제작에 있어서 종이의 질감이나 색을 크게 좌우하는 것으로는 석회발효 일광표백이었으나 잔류물 유 무도 많은 영향을 끼치고 있는 것으로 판명 되었다. 이것은 원료를 채집해 발효시킨 후 씻기의 공정에서 세심한 배려가 없으면 최종적으로 지면(紙面)의 느낌에 크게 영향을 미치는 것으로 확인되었다. 여기서 잔류물의 예로 들 수 있는 것은 석회이다. 석회는 다른 불순물과 다르게 미량이라도 잔류하게 되면 종이 염색에 잔류물에 의한 반점이나 얼룩을 만드는 원인이 되며 그 기능을 잃게 된다. 백죽지의 재현은 회화, 전적, 문서 등의 재현연구에 사용되는 용지나, 별종의 지직화(紙織畵) 재현에 유효할 것으로 생각된다. 그러나 중국원료의 초기 단계 처리에 대해 개선의 여지가 있으며 앞으로 좀 더 깊이 있는 연구가 필요하다고 할 수 있다.

• 분석과학
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• 제13권3호
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• pp.351-356
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• 2000

한지 제조공정 중 발생하는 폐수의 탈색과 최종 슬러지 회수조건에 대해 연구하였다. 잿물삶기 공정에서 생긴 50 mL 폐수의 검은 색은 산화제인 $Ca(OCl)_2$를 2.0g 정도 가하면 효과적으로 탈색시킬 수 있었는데 이는 표백공정 중에 사용되는 과량의 표백제를 재활용하면 매우 효과적으로 탈색시킬 수 있을 것으로 생각된다. 그러나 전기분해적 산화에 의한 탈색은 전혀 효과적이지 못하였다. 최종 슬러지를 회수하는데는 현재 사용하는 고분자 응집제로도 효과적으로 슬러지가 제거됨을 알 수 있었지만 고분자 응집제를 사용할 경우 필히 $Al_2(SO_4)_3$을 사용하여야 하고 슬러지를 제거할 때 함께 나오기 때문에 순수한 섬유질 형태의 슬러지를 얻을 수 없었다. 그러나 triethanolamine과 Triton X-100과 같은 계면활성제를 이용하였을 때 슬러지 회수율은 85% 정도로 고분자 응집제를 이용할 때와 거의 같은 효율을 나타내었고, $Al_2(SO_4)_3$을 사용하지 않아도 되며, 슬러지도 섬유질 형태이었기 때문에 재활용하기에도 좋으리라고 예상된다.