• Title/Summary/Keyword: surface washing

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The Properties of Carbonaceous Desiccant Derived from Phenolic Resin (페놀레진으로부터 유도된 탄소질 수분 흡수제의 특성)

  • Oh, Won-Chun
    • Analytical Science and Technology
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    • v.13 no.3
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    • pp.332-337
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    • 2000
  • The study on the nitrogen adsorption, surface properties and water adsorption capacity of the carbonaceous desiccants derived from phenolic resin was carried out. In the nitrogen adsorption study on the carbonaceous desiccants, Type II isotherm for each sample was obtained. Furthermore, the adsorbed volume decrease with water washing of the desiccant. The $S_{BET}$ of the carbonaceous desiccants was $648.7m^2/g$ before washing and $189.3m^2/g$ after washing, respectively. The morphology of needlelike formation before washing and spherical particle after washing with water were observed from SEM micrographs. Finally, from the water adsorption effects, the percentage of the water loading capacity was 25-63%, and the capacity was good at relatively low humidity.

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Improvement of Dry-blasting Efficiency for Ballast used as Aggregate of Paved Track (포장궤도 골재용 도상자갈의 건식 블라스팅 효율 향상 연구)

  • Lee, Il-Wha
    • Journal of the Korean Society for Railway
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    • v.13 no.1
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    • pp.78-83
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    • 2010
  • On the paved track, the ballast is used as aggregate for the filling layer using the pre-packed concrete technique. The most important condition of aggregate is adhesive strength with mortar. To satisfy this condition, surface of aggregate should be cleaned by water or others. In a paved-track method to be introduced domestically, an environment-friendly dry-washing technology which will replace the water-washing method has been developed. A dry-washing method was designed to blast the crushed weight material with a diameter of 0.3~0.5mm at high pressure to peel the surface of the aggregate. The study was intended to enhance the washing efficiency of dry-blasting technology and to that end, the tests including blasting material, content of fine aggregate depending on time elapsed, content of chloride, LA abrasion rate and compressive strength were conducted to recommend the efficient washing material and the process.

A study on the Functional Properties of Polyester Fiber Treated Titanium Dioxide Photocatalyst (이산화티타늄 광촉매를 처리한 Polyester 섬유의 기능성 연구)

  • Choi, Sei Young
    • Elastomers and Composites
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    • v.49 no.4
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    • pp.336-340
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    • 2014
  • The functionality such as deodorant, antibacterial, ultraviolet shielding of titanium dioxide self-actuated photocatalyst $Weltouch^{TM}$ treated polyester fiber was characterized in conditions without light. The deodorizing capacity was maintained more than 97% reduction irrespective of before washing and after 20 times repeated washing, and antimicrobial capacity was also retained more than 99.9% reduction. Titanium dioxide self-actuated photocatalyst was still maintained to the surface of polyester fiber without separation even after 20 times repeated washing. According to washing durability of polyester fiber, the reduction effect for ammonia was still retained even after 20 times repeated washing as much as before washing. The ultraviolet shielding capacity was still maintained at least 83% irrespective of before washing and 20 times repeated washing.

Preparation of PZI Tapes by Solvent Washing Dry Method (용매세척건조법에 의한 PZT 테입 제조)

  • 신효순;윤석진;김현재
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.05a
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    • pp.300-303
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    • 1999
  • For the fast dry of the aqueous tape, the process which water was replaced by organic solvent was proposed. So-called, 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 all 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 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. The tape casting system was designed for the solvent washing dry and prepared. An homogeneous tape was established by continuous tape casting process.

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Surface Treatment Method for Long-term Stability of CdSe/ZnS Quantum Dots (장시간 안정성을 위한 CdSe/ZnS 양자점의 표면처리 기술)

  • Park, Hyun-Su;Jeong, Da-Woon;Kim, Bum-Sung;Joo, So-Yeong;Lee, Chan-Gi;Kim, Woo-Byoung
    • Journal of Powder Materials
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    • v.24 no.1
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    • pp.1-5
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    • 2017
  • We have investigated the washing method of as-synthesized CdSe/ZnS core/shell structure quantum dots (QDs) and the effective surface passivation method of the washed QDs using PMMA. The quantum yield (QY%) of as-synthesized QDs decreases with time, from 79.3% to 21.1%, owing to surface reaction with residual organics. The decreased QY% is restored to the QY% of as-synthesized QDs by washing. However, the QY% of washed QDs also decreases with time, owing to the absence of surface passivation layer. On the other hand, the PMMA-treated QDs maintained a relatively higher QY% after washing than that of the washed QDs that were kept in toluene solution for 30 days. Formation of the PMMA coating layer on CdSe/ZnS QD surface is confirmed by HR-TEM and FT-IR. It is found that the PMMA surface coating, when combined with washing, is useful to be applied in the storage of QDs, owing to its long-term stability.

Reduction of Microbial Populations on the Surface of Fresh Ginseng by Various Washing Treatments (세척처리에 따른 수삼 표면의 미생물 제어효과)

  • Kim, Hee-Su;Kim, Eun-Jeong;Choi, Jeong-Hee;Hong, Seok-In;Jeong, Moon-Cheol;Kim, Dong-Man
    • Food Science and Preservation
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    • v.17 no.3
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    • pp.405-409
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    • 2010
  • Surface cleaning is both essential and troublesome when a consumer seeks to eliminate soil attached to the surface of fresh ginseng because all ginseng purchased in the market is covered with soil, reflecting the post-harvest situation. To facilitate ginseng use at home, a fresh-cut type of ginseng is required. As a first step toward production of such ginseng, several washing and dipping treatments were investigated with respect to surface cleaning and reduction of microbial populations on fresh ginseng. In terms of microbial distribution on the surface of fresh ginseng, higher levels of viable bacteria (6.63 log CFU/each) and fungi (5.12 log CFU/each) were present on the rhizome head than on other regions of the root. Of the washing treatments tested, hand-brushing was effective for surface cleaning and to reduce microorganism levels on fresh ginseng, but use of a high-pressure water spray followed by hand-brushing was optimally effective. To further reduce the levelsof microorganisms on the surface of fresh ginseng after washing, additional dipping treatments in 70% (v/v) ethanol and electrolyzed acidic water (at pH 2.3) were somewhat effective but showed no significant differences compared with other dipping treatments tested, including a 3 ppm ozone solution, a 200 ppm sodium hypochlorite solution, or hot water at $50^{\circ}C$.

Effect of Fluorination and Ultrasonic Washing Treatment on Surface Characteristic of Poly(ethylene terephthalate) (불소화 및 초음파 수세가 폴리(에틸렌 테레프탈레이트) 필름의 표면 특성에 미치는 영향)

  • Kim, Do Young;In, Se Jin;Lee, Young-Seak
    • Polymer(Korea)
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    • v.37 no.3
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    • pp.316-322
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    • 2013
  • In this study, poly(ethylene terephthalate) (PET) was treated with fluorination and ultrasonic washing treatment for hydrophilic modification of PET film. We measured the change of surface modified PET film surface characteristics using contact angle, surface free energy, FE-SEM, AFM and XPS. After direct fluorination and ultrasonic washing treatment, the water contact angle was measured to be $10.81^{\circ}$, 85% reduction compared to the untreated PET film. Total surface free energy has been measured to be $42.25mNm^{-1}$, 650% increase compared to the untreated PET film. Also RMS roughness has been measured to be 1.965 nm, 348% increase compared to the untreated PET film. Hydrophilic functional group C-OH bond concentration has increased approximately 3 times. These results are attributed to the hydrophilic functional group and cavitation due to chemical etching. From this result, it was suggested that the fluorination-ultrasonic washing treatment method could be useful to make PET film surface hydrophilic.

Effect of Temperature on the Surface Tensions in the Detergency System(I) -Change of Surface Tension Components of Washing Liquids- (온도가 세척계의 표면장력에 미치는 영향(제1보) -세액의 표면장력 성분변화를 중심으로-)

  • Chae, Chung-Hee;Kim, Sung-Reon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.17 no.4
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    • pp.511-517
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    • 1993
  • Changes of the surface and interface tension with temperature for washing liquids and alkanes were measured by FACE surface tensiometer. Using the extended Fowkes' equation, the dispersion and polar force components of the surface tension were estimated. The results were as follows : 1. The surface tensions of washing liquids and alkanes decreased almost linearly with the increase of temperature. 2. The interface tensions of 0.25% DBS/alkane increased slowly with the increase of temperature. In the case of nonionic surfactant solutions, however, the interface tensions with alkanes varied with the number of hydrophilic ethylene oxide(EO) groups. 3. Of the surface tension of water at $20^{\circ}C$, the dispersion force component was 25.3 dyn/cm and the polar force component was 47.8 dyn/cm. As the temperature increased, both the polar and dispersion force components decreased in a similar fashion. 4. The dispersion force component of surface tension of 0.25% DBS solution was 30.0 dyn/cm, and the polar force component was 2.2 dyn/cm at $20^{\circ}C$. The two components decreased with the increase of temperature. 5. As the temperature increased, the dispersion force component of surface tension decreased and the polar force component increased significantly for 0.25% NPPG-7.5EO solution. In the case of 025% NPPG-10EO, both the dispersion and polar force components decreased slowly, but the polar force component is expected to increase from $60^{\circ}C$. However, the polar force component of surface tension decreased with the increase of temperature for 025% NPPG-15EO solution, and at the temperature higher than $60^{\circ}C$ the surface tension is expected to be composed of only dispersion force component.

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Preparation of Commercial Agarose from Jeju Seaweed, Gelidium amansii using DMSO Extraction and EDTA Washing (제주산 우뭇가사리(Gelidium amansii)로부터 DMSO 추출과 EDTA 수세법에 의한 상용화 아가로스 제조)

  • Kang, Tai-Hwan;Lee, Seung-Hong;Baik, Jong-Seok;Kang, Byung-Sik;Lee, Jung-Suck;Lee, Nam-Ho;Jeon, You-Jin
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.44 no.6
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    • pp.635-643
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    • 2011
  • Agar was prepared from Gelidium amansii collected from Jeju Island, South Korea. This agar preparation has high gel strength and low sulfate content compared with G. amansii agar from Morocco. Accordingly, agarose was made from the Jeju agar through the consecutive refining processes of dimethyl sulfoxide (DMSO) extraction and ethylene diamine tetra acetic acid (EDTA) washing. The physicochemical properties of the resulting agarose were compared with those from agarose prepared using only DMSO extraction. Consecutive DMSO extraction and EDTA washing more strongly affected the physicochemical properties of the agarose (purified agarose) compared with the use of DMSO extraction alone. These properties were similar to those of commercial agarose used for electrophoresis. In DNA electrophoresis, the separation and movement speed of the purified agarose were similar to those of the commercial agarose. In a $^{13}C$ NMR analysis, the purified agarose exhibited the same carbon peak as the commercial agarose. When observed under scanning electron microscopy, the agar had an even and smooth surface without irregularities or pores, and the purified agarose had a wide surface area with a large number of pores; the commercial agarose had an irregular surface that would allow the solvent to easily permeate. These results illustrate that the physicochemical properties of agarose prepared from DMSO extraction and EDTA washing were more effective than those observed after DMSO extraction alone; thus, these processes used in succession will be useful in agarose industries.

Effect of Denier and Dyestuff Structure on Washing Fastness of Polyester Fabric (섬도와 염료구조가 폴리에스테르 직물의 세탁견뢰도에 미치는 영향)

  • 강연희;백지연;이재웅;김삼수;허만우;이난형
    • Textile Coloration and Finishing
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    • v.13 no.3
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    • pp.180-187
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    • 2001
  • Generally, polyester microfiber has much greater dye uptake than that of regular ones. In spite of high dye up-take visual shade depth of dyed fabric decreases with smaller denier, which results in poor washing fastness of dyed fabric. In this study, in order to investigate the washing fastness, polyester microfiber fabric was dyed by using two type of disperse dyes and treated with 3 different reduction clearing methods. The reduction clearing methods in this study are normal alkaline reduction clearing, $N_2$ gas replacement method, and ultrasonic treatment during reduction clearing. The results were as followings ; The most important factors affecting the washing fastness of polyester artificial suede fabric were found to be the reduction clearing method, the chemical structure of used disperse dyes and the structure and denier of fibers. It was also obtained that the heat treatment of dyed fabric decreased the washing fastness due to the dye migration from inner phase to surface.

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