• 한국지역사회생활과학회지
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• 제20권4호
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• pp.515-522
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• 2009

This study was to develope the functional work clothing for livestock farmers. Major demanding performances for livestock work clothing are anti-soil and anti-bacterial properties. On surveys, functional fabrics that have anti-soil, anti-bacterial and waterrepellent performances were developed and the work clothing that have adaptability to body movements were manufactured. The designs of livestock working clothes were two piece and one piece with rubber bade in waist. The thermal responses of subjects wearing the winter working clothes for stock farming worker were measured in the climate chamber($17^{\circ}C$, 40% R.H.). The main results were summarized as follows: Total body weight loss was smaller and the mean skin temperature was higher in developed clothes than the market product. Clothing micro-climate of developed clothes was lower than the market clothes. Subjective sensation did not have significant differences. From the results of various evaluation, developed garments for livestock workers showed better efficiency than the market product.

• Tribology and Lubricants
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• 제35권5호
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• pp.294-299
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• 2019

Most previous studies on water repellent surfaces using lasers rely on the use of pico- or femtosecond lasers. However, in industrial application, these methods have the disadvantages of high cost and low efficiency. In this study, we implement a hydrophobic surface using a high-power general-purpose diode laser. We have fabricated the microsurface using laser groove processing technology, and we present the correlation of wettability characteristics with space and width. The metal material is stainless steel (SUS 304), and the groove height during laser processing is set to $30{\mu}m$ to evaluate the wettability based on the gap and width of various grooves. Results show that the contact angle of the groove-shaped surface is increased by $40^{\circ}$ or more as compared with the surface without patterning, and the contact angle in the parallel direction is greater than that in the perpendicular direction. Results from contact angle hysteresis measurement experiments show that the groove width has a greater influence on the contact angle history than does the gap between grooves. In addition, the coating reveals that the contact angle can be increased using a chemical method and that the laser grooving process can further improve the wetting properties of the surface.

• 한국기계가공학회지
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• 제17권5호
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• pp.8-15
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• 2018

Films with special properties (e.g., water-repellent films, optical films, anti-reflection films, and flexible films) are referred to as functional films. Recently, there has been interest in fine patterning methods for film fabrication. In particular there have been many studies that use a UV nanoimprint process involving a UV curing method. In this paper, a polymer film was fabricated by the UV nanoimprint process with a micro-pattern, and its durability was evaluated by a wear test and a nano-indentation test. The film mechanical properties (such as coefficient of friction, hardness, and modulus of elasticity) were measured. Moreover, the choice of PUA type resin used in the UV nanoimprint process was confirmed to impact the durability of the thin film. Despite making the polymer film samples using the same method and PUA type resin, different coefficient of friction, hardness, and modulus of elasticity values were obtained. PUA 4 resin had the most favorable coefficient of friction, hardness, and modulus of elasticity. This material is predicted to produce a high durability functional film.

• 공업화학
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• 제5권2호
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• pp.345-356
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• 1994

내구유연발수제를 제조할 목적으로 전보에서 합성한 poly(OMA-co-DAMA)[PODC], poly(DMA-co-DAMA)[PDDC], poly(EMA-co-DAMA)[PEDC] 각각의 양이온화물, 본 실험에서 합성한 지방산 카르바미드의 양이온화물(ODTCC), 왁스류 및 유화제들을 블렌드시켜 발수제 PODCW, PDDCW, PEDCW를 각각 제조하였다. 발수제 PODCW, PDDCW, PEDCW 각각을 면직물에 단독 및 수지병용으로 처리하여 내세탁성, 인열강도, 방추도 및 접촉각 등을 측정해 본 결과, 물성의 향상을 가져왔다. 그러나 발수도는 PODCW의 경우 80 정도로 사용 가능하였으나, PDDCW와 PEDCW의 발수도는 현저히 저하되었다. 제조된 발수제의 적정 열경화온도는 $140^{\circ}C$, 적정 사용농도는 3wt%이었고, 사용된 발수제용 촉매 중 아세트산나트륨이 가장 좋았으며, 촉매의 사용농도는 0.6wt%가 적당하였다. 또한 발수제와 셀룰로오스 섬유화의 반응메카니즘을 규명하고 내세탁성 결과치를 검토한 결과, 제조된 발수제가 내구성 발수제임을 입증하였으며, SEM으로 발수처리된 면직물의 표면구조를 관찰하였다.

• 한국작물학회지
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• 제42권4호
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• pp.378-383
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• 1997

벼 품종 안중벼를 공시하고 조류 기피제인 methiocarb을 여러 가지 제형으로 제조하고, 약량을 달리하여 최아 볍씨에 처리한 후 새 피해, 초기 생육 및 약해를 조사한 결과를 요약하면 다음과 같다. 1. <시험 1> Methiocarb 제형별 새 피해 경감 효과와 모의 생육 1) Methiocarb의 처리는 제형과 약량에 관계없이 새에 의한 피해가 없었으나 무처리구는 5일후에 30％, 10일 후에 85％, 15일 후에는 100％의 피해를 입었다. 2) 입모율은 처리간 유의한 차이가 없었으나, 파종 15일 후의 초장과 잎수는 methiocarb 15g 처리구에서는 methiocarb 10g 처리구에 비하여 유의하게 작아서 약해가 있었다. 3) 파종 35일 후 약해에 대한 회복 상태를 보면 methiocarb＋thiram 15g 처리구는 초장이 유의하게 작았으나, methiocarb FS 15g처리구 초장은 무처리구와 큰 차이가 없었다. 2. <시험 2> Methiocarb 제형의 벼 종자 분의에 의한 본답 시험 1) Methiocarb 처리구는 무처리구에 비하여 새 피해가 유의하게 경감되는 것으로 나타났다. 2) 파종 25일 후의 초장과 잎수는 모든 처리구에서 유의한 차이를 보이지 않았다. 3) 파종 10일 후에는 약제 처리구는 경후한 약해가 발생하였으나 파종 20일 후에는 무처리구와 큰 차이가 없었다.

• 한국식품과학회지
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• 제37권3호
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• pp.364-371
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• 2005

개발된 항균 포장 원지를 이용하여 포장 봉지(packaging bag)와 골판지 포장 상자(corrugated box)를 제작하였고, 여기에 과채류를 포장하였을 때 일반 포장 봉지나 골판지 상자에서 포장된 과채류 보다 변패 미생물의 발생이나 생체중 감소가 상당히 줄어들었다. 이는 BAAG에 의해 과채류의 변패에 관여하는 미생물의 생육을 차단하였고, 제올라이트에 의해 과채류의 조직을 빠르게 연화시키는 기체들인 에틸렌가스, 이산화탄소 및 산소가 제거되었으며, AKD에 의해 과채류가 보유한 수분 손실을 최소한으로 일어나게 하였기 때문이다. 결론적으로 BAAG, 제올라이트, 그리고 AKD로 처리된 포장 원지를 이용하여 제작한 포장대(packaging bag)과 골판지 포장 상자는 저장 과채류의 선도를 유지하는 데 탁월한 효과를 발휘하였고, 기능성 첨가제의 처리로 인한 제조 원가의 상승은 폐기 과채류의 양이 감소하면서 상쇄시킬 수 있었다. 따라서 일반 골판지 상자에 저장된 과채류보다는 기능성 골판지 상자에 저장하는 방법이 보다 경제적인 저장 방법이 될 수 있음을 확인하였다.

• 복식문화연구
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• 제19권3호
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• pp.612-621
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• 2011

The process of making or cultivating indigo dyes is very cumbersome and complex. The dye extraction and dyeing methods using general plant dye, moth repellent dye, fast acting natural dye, and other dyes are very different. This research investigates the extraction of indigo dye and liquid dye extraction of polygonum(indigo) plants using calcium oxide water. While extracting indigo dye the concentration of purified indigo dye may be controlled by adjusting the pH level. Due to the various uses of dyes the adjustment of surface color must be considered. In regard to the change according to different concentrations of reducing agents, it was found that cotton fabrics and ramie fabrics show the highest color difference at 0.4% and 0.3% respectively. As the reduction temperature increases, the color difference increases as well. The maximum color difference was found to appear at $90^{\circ}C$. Cotton fabrics and ramie fabrics showed 70.55 and 67.01 respectively. The color difference increases as the concentration of dyes increases, but at a concentration of 300%, cotton fabrics was found to show 6.22PB in H value using the Munsell color system, containing purple and blue color. The pH of the polygonum dyes extracted through this experiment were adjusted by adding calcium oxide to the experimental water, without directly adding calcium oxide to the liquid polygonum extract. In a refine state, it was mixed with polygonum extract to extract a more refine and highly concentrated indigo dye. When lye and reducing agents are added to extracted indigo dye and sealed for long-term storage, it can be effective and easily used for dyeing.

• Environmental Engineering Research
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• 제20권2호
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• pp.127-132
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• 2015

Perfluorooctane sulfonate (PFOS) and Perfluorooctanoic acid (PFOA) are persistent environmental pollutants, extremely stable, and possibly adversely affect human health. They are widely used in many industries and consumer goods, including sunscreen products. These substances are stable chemicals made of long carbon chains, having both lipid- and water-repellent qualities. The research objectives are (1) to find the most effective method for the preparation of semi-liquid samples by comparing solid phase extraction (SPE) and centrifugation after Pressurized liquid extraction (PLE), and (2) to determine the contamination levels of PFOS and PFOA in waterproof sunscreen samples. All sunscreen samples were analyzed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Sunscreen samples were purchased from domestic and international brands sold in Thailand. Special chemical properties were considered for the selection of samples, e.g., those found in waterproof, sweat resistant, water resistant, and non-stick products. Considering the factors of physical properties, e.g., operation time, chemical consumption, and recovery percentage for selecting methods to develop, the centrifugation method using 2 mL of extracted sample with the conditions of 12,000 rpm and $5^{\circ}C$ for 1 hour after PLE was chosen. The highest concentrations of PFOS and PFOA were detected at 0.0671 ng/g and 21.0644 ng/g, respectively. Even though present concentrations are found at ng/g levels, the daily use of sunscreen products is normally several grams. Therefore, a risk assessment of PFOS and PFOA contamination in sunscreen products is an important concern, and more attention needs to be paid to the long-term effects on human health.

• 한국염색가공학회지
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• 제21권6호
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• pp.1-11
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• 2009

Super-hydrophobic surface, with a water contact angle greater than $150^{\circ}$, has a self cleaning effect termed 'lotus effect'. We introduced super-hydrophobicity onto aramid/rayon mixture fabric with dual-scale structure by assembling silica nano-sol. Mixture fabric was treated with silica nano-sol, fluoric polymer using various parameters such as particle size, concentration. Silica nano-sol size were measured using particle size analyzer. Morphological changes by particle size were observed using field emission scanning electron microscopy(FE-SEM), contact angle measurement equipment. The contact angle of water was about $134.0^{\circ}$, $137.0^{\circ}$, $143.0^{\circ}$, $139.5^{\circ}$ and $139.0^{\circ}$ for mixture fabric coated with 100.2nm, 313.7nm, 558.2nm, 628.5nm and 965.4nm silica nano-sol, compared with about $120.0^{\circ}$ for mixture fabric coated with fluoric polymer. When we mixed particle sizes of 100.2nm and 558.2nm by 7:3 volume ratio, the contact angle of water was about $146.2^{\circ}$. And we mixed particle sizes of 313.7nm and 558.2nm by 7:3 volume ratio, the contact angle of water was about $141.8^{\circ}$. Also we mixed particle sizes of 558.2nm and 965.4nm by 7:3 volume ratio, the best super-hydrophobicity was obtained. In this paper, we fabricated the water-repellent surfaces with various surface structures by using four types of silica nano-sol, and we found that the dual-scale structure was very important for the super-hydrophobicity.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 춘계학술발표회
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• pp.45-45
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• 2018

We had already reported the successful germination for green pods of purple lady's slipper orchid (Cypripedium macranthos Sw.). The green pod methods is to take immature seeds in green capsules, sterilize the capsule, and take out the sterile seeds. This method, however, needs very critical time of harvest. The critical time of seed harvest changes depending upon the species, condition of the specimen, and climatic influence, and the right time lies between 5 and 12 weeks after fertilization. In this study, the mature seeds were collected after 120-130 days with hand-polination of lady's slipper orchids. Mature seeds are usually dormant and it has to be overcome, either with hormone or storing the seeds near freezing for two or three months to break dormancy. The seeds were first surface sterilized with 70% ethanol and then transferred 1% NaOCl for 10-15 minutes, followed by rinses 3 times with sterilized distilled water. The cypripedium seeds consists of an embryo within a seed coat known as a testa. The testa is water repellent and the seed has a large air space between the embryo and testa so the seed tends to float on water. We had resolved the problems with vacuum pump to soak water into the testa before sterilization. The seeds were placed on liquid or agar solidified germination media. Cultures were incubated at $24{\pm}1^{\circ}C$ in dark. The seeds were germinated in 6-8 weeks in liquid suspension culture (germination percentage over 18%); however, the seeds on agar solidified media took more than 5 months to germinate and the germination percentage less than 5%. The most effective media for liquid culture was 1/4 strength Murashige and Skoog (MS) medium with 50 ml/l coconut water ($4brix^{\circ}$) at pH 5.8.