• 상하수도학회지
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• 제30권1호
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• pp.87-97
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• 2016

First of all, Fe or/and Mn immobilized granular activated carbons (Fe-GAC, Mn-GAC, (Fe, Mn)-GAC) were synthesized and tested to remove arsenate (As(V)). The results in batch test indicated that Fe-GAC removed As(V) effectively, even though the surface area of Fe-GAC was reduced largely. Moreover, adsorption isotherm test indicated that the experimental data fit well with Langmuir model and the maximum adsorption capacity ($q_{max}$) of Fe-GAC for As(V) was $3.49mg\;g^{-1}$, which was higher than GAC ($2.24mg\;g^{-1}$). In column test, the simulated water, which consisted of As(V), Fe(III), Mn(II) and Ca(II) in tap water, was used. Fe-GAC column with 1 hr of pre-washing time treated As(V) effectively while GAC column removed Fe(III) better than Fe-GAC column. Moreover, the increasing pre-washing time from 1 to 9 hour in Fe-GAC column enhanced Fe(III) removal with little negative impact of As(V) removal. Mostly, the column filled with Fe-GAC and GAC (i.e. the mass ratio of Fe-GAC:GAC = 2:8) showed the higher treatability of both As(V) and Fe(III), even it operated with 1 hr pre-washing time.

• 한국산업융합학회 논문집
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• 제26권4_2호
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• pp.561-570
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• 2023

This study was to evaluate the effect of different rinsing times and methods on the accuracy of temporary prostheses fabricated by 3D printing method. Sixty temporary prostheses were fabricated with LCD types of 3D printer(Halot-Sky, Creality, Shenzhen, China) and divided into six groups (n = 10) based on rinsing times and methods. All specimens were rinsed with 99% isopropanol alcohol for 5 and 10 min using three methods-hand washed, ultrasonic cleaning, and automated washing. All specimens were polymerized for 3 minutes under the same conditions. The marginal and internal gaps of specimens were examined using a replica technique. The light-body silicone thickness was measured at 6 reference points(Absolute marginal discrepancy, Marginal, Chamfer, Axial, Angle, and Occlusal gap). All measurements were performed by a stereomicroscope. Reference point images were taken at 100× magnification and then measured using an image analysis program. Statistical analysis was performed using Two-way ANOVA, One-way ANOVA, and the Kruskal-Wallis test (p = .05). The marginal and internal gaps were statistically different according to the rinsing methods and rinsing times(p < .001). In the rinsing time, the temporary prosthesis rinsed for 5 minutes group showed higher accuracy than 10 minutes group. In the rinsing method, the hand washing group showed higher accuracy than the automated washing group.

• 농업생명과학연구
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• 제45권3호
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• pp.81-88
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• 2011

본 연구에서는 딸기의 냉장 및 상온 저장 시 일반세균, pH, color, firmness 등의 품질특성에 있어 염수 세척에 따른 영향을 분석하였다. 시료는 세척하지 않은 대조구, 염수세척 시료구, 염수세척 후 물기제거한 시료구 세 가지 종류로 준비하였다. 일반세균의 경우 염수세척 후 물기제거한 경우에 염수세척 시료구와 비세척 대조구에 비해 세균수가 저감화되었으며, 대수증식기가 나타나지 않았다. pH의 경우, 비세척 대조구와 염수세척 시료구에서는 다소 감소했으나, 염수세척 후 물기를 제거한 시료구에서는 거의 변화가 없는 것으로 나타났다. 적색도는 비세척 대조구와 염수세척 후 물기제거 시료구에서 저장기간이 경과함에 따라 증가되었으나, 염수세척 시료구에서는 감소되었다. 경도의 경우 $4^{\circ}C$에서 저장했을 때, 저장 간에 큰 변화를 보이지 않았다. 결론적으로 딸기를 염수세척하여 물기를 제거할 경우, 저장기간을 크게 연장할 수 있을 것으로 사료된다.

• 대한환경공학회지
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• 제27권8호
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• pp.787-798
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• 2005

본 연구에서는 폐광산지역에서 발생되는 폐기물인 광미를 대상으로 토양세척공정을 이용하여 다양한 세척용매와 농도, 그리고 추출시간에 따른 중금속의 추출특성을 파악하였다. 세척용매로는 물, HCl(0.1, 0.3, 1.0 N), EDTA(0.01, 0.05, 0.1 M), SDS(0.1, 0.5, 1.0%)를 이용하였다. 그 결과, 물과 SDS 용매에서 Zn과 Cd이 Pb과 Cu보다 높은 추출효율을 보였지만, 전체적으로는 1%이하로 중금속의 추출에 효과적이지 못하였다. 그러나, SDS에서 Pb과 Cu의 추출효율은 추출시간이 길어질수록 증가하였다. HCl과 EDTA를 이용한 중금속의 추출은 물과 SDS보다 빠른 추출경향을 보였고, 대부분의 중금속이 6시간 이내에 추출되었으며 용매의 농도와 무관하였다. 6시간 이후에는 느린 추출경향을 보였지만 세척용매의 농도에 따라 좌우되었다. 또한, 용매의 농도가 증가할수록 추출경향은 빨라졌고, 추출 효율도 증가하였다. 추출효율은 1.0 N HCl에서 Cd>Pb>Zn>Cu로, 0.1M EDTA에서 Pb>Cd>Zn>Cu 순으로 높았다. 농도증가에 따른 추출효과는 HCl에서 Pb이, EDTA에서 Pb과 Cd이 가장 컸으며, 중금속제거를 위한 6시간이상의 추출은 비효과적이었다.

• 분석과학
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• 제30권5호
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• pp.270-278
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• 2017

흰색 면(cotton), 폴리에스터(polyester), 레이온(rayon), 나일론(nylon) 천(fabric)에 혈액이 흡수 및 침투되는 특성을 연구하였다. 두께와 직조방법(직물 및 편물)이 다양한 천을 두 번 접어서 천이 4개 층으로 되도록 한 후 여기에 $100{\mu}L$의 혈액을 떨어뜨리고, 이 혈액이 천으로 침투되는 특성을 관찰하였다. 그 결과 혈액이 침투되는 천의 층 수 및 혈액의 모양은 실험에 사용한 천의 섬유 성분, 두께, 직조방법에 따라 달라진다는 것을 알 수 있었다. 혈액을 묻힌 천을 3일 동안 건조한 후 수돗물을 이용해 손빨래하고, 천에 남아있는 잠재혈흔을 Lumiscene으로 증강하여 혈액이 천에 부착되었던 모습과 대조하였다. 그 결과 천의 종류에 따라 혈흔이 세탁되는 특성이 다르게 나타났다. 또한 혈액이 침투되었던 곳의 형광이 주변의 형광보다 강하게 나타나는 것을 확인할 수 있었다. 그러나 세탁 과정에서 혈액이 물리적으로 문질러져서 원래 혈액이 부착된 모습과 다른 모습의 형광을 관찰할 가능성이 있다는 것을 알 수 있었다. 천에 부착된 혈흔을 건조시키는 시간에 따른 세탁특성도 관찰하였다. 다양한 천에 $100{\mu}L$의 혈액을 떨어뜨린 후, 0, 1, 12, 24, 72시간 및 7일 동안 건조하고, 이 천을 세탁한 후 Lumiscene으로 혈흔을 증강하였다. 그 결과 폴리에스터를 제외한 모든 천에서 혈액을 건조하는 시간이 길어질수록 혈흔의 형광이 강하게 나타나는 것을 확인할 수 있었다. 또한 천에 따라서는 혈흔을 7일 동안 건조하면 혈액이 부착되었던 곳보다 그 주변에서 형광이 더 강하게 나타나는 현상을 관찰할 수 있었다.

• 패션비즈니스
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• 제22권4호
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• pp.106-117
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• 2018

The present study was conducted to investigate dyeing properties and functionality of silk fabrics dyed with extracts from buckwheat skin. Comparative results of color strength(K/S) values of dyed silk fabrics were studied to quantify the effects of dye concentrations, dyeing temperatures, dyeing time and the pH; the effect of mordants; and color changes. And also evaluated the fastness, antimicrobial property, ultraviolet protection properties of the dyed and mordanted silk fabrics. The color strength(K/S) values of silk generally increased depending on the increasing dye concentration, dyeing temperature, and dyeing time. And the highest color strength values were obtained at a dye concentration of 100%(v/v), a dyeing temperature of $90^{\circ}C$, a dyeing of time 80 minutes, and a dyebath of pH 2. The color fastness to light of dyed and mordanted silk fabrics were found to be good, and the drycleaning and rubbing fastness were excellent. The fade of washing fastness was not good, however, the stain of washing fastness and perspiration fastness showed relatively good grade. The Al, Cu, Fe mordanted silk fabrics(except Fe for Klebsiella pneumoniae) showed 99.9% reduction rate. The ultraviolet protection properties of the mordanted fabrics were generally improved. Moreover, the Cu and Fe mordnared fabrics showed very exceptional ultraviolet protection factors.

• 한국농촌생활과학회지
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• 제8권2호
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• pp.83-91
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• 1997

In this study, the dyeability of natural dye extracted from chesnut shell was investigated in order to explore the using of discarded chesnut shell in natural dyeing. Dyeing experiments were done in various dyeing conditions which were different in dyeing temperature, concentration of dyebath, dyeing time, repitition of dyeing. pH of dyebath and mordant with 3 kinds of experimental fabrics silk, nylon and cotton. Color and color difference ($\Delta$ E) of every dyed fabrics were measured and color fastness to drycleaning, washing, perspiration and light were measured. The results were as follows ; 1. The dyebath became thicker with time and temperature of extraction and the characteristics of dyebath prepared chesnut shell 1g : distilled water 30㏄ after 3 hrs-boiling were 32,400ppm and 3.7pH. 2. The dyeabilities of silk and nylon fabrics were good and color difference was increased with dyeing temperature, concentration of dyebath, dyeing time, number of repitition and acidity of dyebath. But the dyeability of cotton was very poor compared to silk and nylon. 3. Without the treatment of mordant, the dyeability of silk was little lower than that of nylon, but after the treatment of mordants it became higher than nylon. After the treatment of mordant Cu and Fe, the dyeability of cotton was increased although the natural dye from the chesnut shell was hardly absorved in cotton without mordant. 4. On the whole, the colorfastness of dyed silk and nylon were very good except the colorfastness to washing in silk and the colorfastness to light in nylon.

• 한국의류학회지
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• 제38권6호
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• pp.942-952
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• 2014

Winter outerwear includes various clothes such as classical jackets/coats, padded jackets/coats, wind breakers, leather and fur jackets/coats. This research surveyed care-label instructions attached to 100 jackets/coats dropped off at five drycleaners in the Gyungin area. University students' perception and attitudes towards care labels and management of winter outerwear were examined using a questionnaire. Data collected from 230 respondents were analyzed by frequency analyses, t-tests, ANOVAs and Duncan tests with PASW 20.0. Half of the padding jackets/coats were labelled to be dry cleaned and dry cleaning was more excessively labelled than necessary. University students confirmed more care symbols than fiber compositions such as more at time of cleaning than at purchasing. Clothing-related major students understood care label symbols better than non-clothing major students. Consumers laundered some winter outerwear at home, even though they thought dry cleaning was a proper cleaning method. The appropriate cleaning method for padded jackets/coats is laundering; however, consumers who answered dry cleaning as an appropriate method were three times as those who answered washing, and those performed dry cleaning were two times as those who performed washing. Winter outerwear manufacturers should provide adequate and more specified care-information to consumers in order to maintain initial appearance and performance over longer periods.

• 한국식품저장유통학회지
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• 제6권1호
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• pp.1-6
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• 1999

Fresh gingers, harvested in Seosan, Choongcheongnam-do, were pre-treated by a washing-pasteurizing-drying process, a curing process, and non-treated, respectively. Then they were stored in a lab-scale storage room(12$^{\circ}C$, >92%RH) to investigate the effect of pre-treatment methods on the quality changes during long-term storage. Weight loss of ginger during storage showed ranges in 0.7∼4.3%, and the weight of gingers pre-treated by washing-drying process showed a tendency to change less than those treated by curing. After storage of 130 days, spoilage rates were about 20% in non-treated, 11% in curing treated, and 12% in washing-drying treated ginger,, showing the effect of pre-treatment. The final rate of sprouting was 13∼15% regardless of treatment methods. The firmness of gingers showed a tendency to decrease in stored ginger for the longer period; however, the values were ranged from 1,200 to 1,400 g/$\textrm{cm}^2$, that is hard enough to show a marketable quality. The contents of reducing sugar showed a tendency to increase with the lapse of storage time.

• The Korean Journal of Ceramics
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• 제7권1호
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• pp.16-19
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• 2001

For the fast dry of the aqueous tape, the process which water was reaplaced by organic solvent was proposed. Socalled, it was the solvent washing dry. Three organic solvents (methanol, ethanol and acetone) were selected for the washing solvent. The weight loss of the washed tapes was measured to evaluate the dry rate of the tapes and dried tapes were examined the generation of the cracks with the variations of the organic solvent and the washing time. Methanol, ethanol and acetone were available organic solvents for this method. The tapes washed in methanol, ethanol and acetone were dried rapidly for twenty minutes. After thirty minutes, the weight losses were not found any more, The solvent of the lower surface tension can decreases the crack of dried tape. If solvent substitutes water completely, though it was fast dried, crack can be eliminated.