• 제목/요약/키워드: whiteness

검색결과 421건 처리시간 0.027초

Graft 공중합물의 광퇴색에 관한 연구(제1보) -백색도 변화에 대하여- (A Study on the Photofade of Graft Copolymer (Part I) -for variance of whiteness-)

  • 조경래
    • 한국의류학회지
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    • 제7권1호
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    • pp.11-16
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    • 1983
  • Variance of whiteness after graft copolymerization of acrylonitrile, methylmethacrylate and acrylamide onto bleached cellulose using Ce(IV) salt as initiators and the effect of homopolymer on the grafted fibers by photo-irradiation were studied. Also, the development of Yellowing were determined after carbon-arc radiation in a Fade-o-meter. The results were as follows: (1) Variation of whiteness of grafted cellulose fibers were influenced by graft-ratio, Inorganic-Organic Balance (IOB) of functional group in used monomers and adhering homopolymers on the grafed fibers. (2) Yellowing was not affected by the concentration of Ceric Ammonium Nitrate directly during reaction (eg. 0.008>0.006>0.014 M).

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Effect of Fluorescent Whitening Agent and Tinting Dye on Optical Properties of Paper

  • Wang Li-Jun;Yoon Byung-Ho
    • 펄프종이기술
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    • 제37권5호통권113호
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    • pp.8-14
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    • 2005
  • The difference of whiteness, brightness and lightness was clearly explained in this paper by use of a tinting dye and a fluorescent whitening agent which are commercially widely used to make paper look whiter. Other optical properties such as tint, color shade, and color difference were also discussed. It is concluded that in comparing two tinting dyes, lightness (L*) is the most important property to be compared, while whiteness data should be used in caution in order not to surpass its significant range, and a*, b* values can also be used to find the change of color shades together with ${\Delta}E$ as color difference. In comparing two fluorescent whitening agents, whiteness or brightness values are most important to be compared, but lightness values are not suitable for this purpose; a*, b* and color difference ${\Delta}E$ can also be referred, but with less significance.

미국의 '백인성'(whiteness)의 확장성 및 배타성 고찰 (A Study on Expandability and Exclusiveness of American 'Whiteness of America')

  • 이수영
    • 미국학
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    • 제42권2호
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    • pp.1-29
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    • 2019
  • The recent census project that non-Hispanic White will be minority in thirty years has been accepted by the conservative media and politicians as the factor that threatens the authentic American national identity. The concerns about the majority-minority population chance influenced the election of Donald Trump who explicitly claimed the restriction of immigration, promising strong controls over the entry of undocumented immigrants. In the process, 'white-nationalism' based on the connection of racial whites and authentic American identity has been central issues in American society. In this sense, this paper examines who has been included/excluded from 'racial Whites' throughout the American history relating to the American identity politics and how these processes have shown the covert strategies of the whites for maintaining their privileges.

반응성 염료에 의한 견날염에 관한 연구(단보) I. 백색발염에 대하여 (A Study on the Silk Printing with Reactive Dye.)

  • 정인모;이용우
    • 한국잠사곤충학회지
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    • 제32권2호
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    • pp.110-112
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    • 1990
  • The influence of the concetration of the discharging agent on some properties of silk fabric dyed with reactive dyes studied. The tensile strength, yellow index and whiteness were investigated as parameters to determine the effect of the dischanging agent. The results were summarized as follows ; 1. The tensile strength and the yellow index decreased with the increase of the concentration of the discharging agents. 2. The whiteness depended on both of the type and the concentration of the discharging agent.

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Major Characteristics Affecting the Sensory Quality of Rice Marketed in Korea

  • Jang, Eun-Hee;Kim, Qui-Woung;Kim, Hoon;Kim, Dong-Chul;Lee, Se-Eun;Kim, Sang-Sook
    • Food Science and Biotechnology
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    • 제17권1호
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    • pp.66-71
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    • 2008
  • A total of 284 milled rice (MR) marketed in Korea were analyzed for grading characteristics (head rice, broken kernels, chalky kernels, and damaged kernels%), color characteristics (L-, a-, b-values, and whiteness), protein content (%), and the cooked rice (CR) sensory quality to investigate the key characteristics affecting the overall sensory quality of rice marketed in Korea. Relatively high correlation with the overall sensory quality of the CR was found in color characteristics such b-value of the CR (r=-0.779) and MR (r=-0.545), the a-value of the CR (r=0.513), and the whiteness (r=0.298) of the MR, compared to protein (r=-0.150), and the moisture (r=0.158) contents of the MR and the percentage of head rice (r=0.195). Partial least squares (PLS) regression of the CR b-value with various characteristics of the MR showed that CR b-value was increased with MR b-value effectively, followed by protein content, damaged kernels, chalky kernels, and colored kernels of MR while it was decreased with whiteness and moisture content for the MR.

쌀의 수분함량별 Tempering에 따른 제분 및 쌀가루의 특성 (Milling and Rice Flour Properties of Tempering Condition on Moisture Content of Rice)

  • 김형열;이병영;유효숙;함승시
    • 한국식품저장유통학회지
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    • 제6권1호
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    • pp.76-80
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    • 1999
  • Power consumption, mesh size, moisture content, color difference, amylogram of rice flour milled with the water soaked rice were compared with that of rice using dry pin mill process. The rice was soaked in 23, 24, 25, 26% of water for 10hr, independently. The more rice had moisture content, the less power consumption was needed. Power consumption to mill the rice soaked in 25% of water was less than that of dry rice by 6.8kW/100Kg. Moisture content of rice flour from the rice soaked with 25% of water was 2% higher than that of rice flour from the rice soaked with 23% of, water. Population of flour particle from the rice soaked with 24-25% of water was 45.7∼46.25 of 60 mesh, 9.7∼10.4% of 80∼100 mesh and 7.7∼8.1% of 100 mesh. Gelatinization temperature of rice flour from the rice soaked with 23% and 24∼25% of water was 65.70C and 64.50C, independently. Temperature of rice flour from the rice soaked with 23% 24∼25% of water sith minimum viscosity was 85.50C and 88.4∼88.70C, independently. Brightness and whiteness of the rice flour from the rice soaked with 24∼25% of water were 95.90∼95.95 and 905.82∼95.94, independently. Brightness and whiteness of the rice flour from the soaked rice were 1.2 and 1.7 higher than that of rice flour from the dry rice, independently.

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정백공정 중 연삭공정이 쌀 품질에 미치는 영향 (Effect of Abrasive Processing in the Milling Process on the Quality of Rice)

  • 강태환;녕효봉;한충수;조성찬
    • Journal of Biosystems Engineering
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    • 제35권3호
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    • pp.169-174
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    • 2010
  • This study was conducted to investigate the effect of abrasive processing and non abrasive processing in the milling process on the quality of rice. The effect was analyzed based on the factor such as whiteness, grain temperature, moisture content, crack and broken rice ratio. The results were as followings. Whiteness of abrasive rice was the same as non abrasive rice. The rice temperature increase of abrasive rice was $1.6^{\circ}C$ lower than non abrasive rice. The crack ratio was increased in the process of milling and non abrasive rice showed higher values than abrasive rice. The broken rice ratio of the using abrasive processing was about 0.05% lower than that of non abrasive processing. The moisture content decreased in the process of milling regardless of the use abrasive rice milling machine.

Ozone($O_{3}$)을 이용한 선직물의 표백과 양색성에 관한 연구 (A Study on the Bleaching and Dyeing Properties of Cotton Fabrics Treated with Ozone($O_{3}$))

  • 조환;우현석;정희천
    • 한국염색가공학회지
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    • 제7권1호
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    • pp.32-42
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    • 1995
  • In order to reduce the amount of waste water generated from textile dyeing process and processing water, cotton fabric was bleached with ozone in ozone/water contact system, and dyed. The results obtained from the measurement of whiteness, reflectance, tensile strength, color difference, and K/S value of treated samples were as follow : 1) In ozone bleaching, factors affect whiteness most are treatment time and ozone dosage. As treatment time is lengthened, whiteness increases. Futhermore, bleaching effect is high in acidic treatment, but low in alkaline treatment. 2) As bleaching goes on, maximum absorption wave length shifts to shoter wavelengths. 3) As treatment time is lengthened or pH of treatment is low, tensile strenth of treated fabric decrease. 4) In all cases, color difference of dyed cotton fabrics in above 2% o.w.f. dyestuff concentration don't go beyond 1∼2 AN unit, compared with standard.

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제지용 형광증백제의 열 견뢰도에 대한 연구 (Study on the Thermal Fastness of Fluorescent Whitening Agents)

  • 김철환;이지영;김병호;최재성;임기백;김다미
    • 펄프종이기술
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    • 제44권1호
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    • pp.10-15
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    • 2012
  • Fluorescent whitening agents (FWAs) are used extensively in the paper industry to improve the optical properties. FWAs are neither photochemically nor thermally stable, and thereby the papers containing FWAs can be damaged by external heat. We observed that the CIE whiteness, ISO brightness and fluorescence index of the commercial papers decreased with the thermal treatment and thought that the thermal fastness of FWAs was the main factor affecting the thermal stability of the papers. Thus, the model papers treated with three types of FWAs were manufactured respectively and the thermal stability of FWAs was identified by determining ${\Delta}$ CIE whiteness and ${\Delta}$ fluorescence index.

반복 세척시 형광증백제에 의한 증백효과와 색상변화 (The Effect of Fluorescent Whitening Agents on the Whiteness and the Shade of Fabrics in Repeated Washings)

  • 윤혜신;정혜원
    • 한국염색가공학회지
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    • 제12권3호
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    • pp.192-198
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    • 2000
  • Influence of the fluorescent whitening agent(FWA)'s adsorption on the whiteness of cotton and on the color change of the dyed fabrics was investigated by repeating wash cycles. Cotton 100% and cotton60/polyester40 blended fabrics were dyed pink, blue and yellow, and cyanuric chloride diamino stilbene(CC/DAS) and distyryl bisphenyl(DSBP) were used for the FWA with laundry detergents. Fabrics were washed at $20^\circ{C}$ with Terg-o-tometer. The FWA adsorption amount was measured by the absorption intensity for the pyridine-water extracted solution. The FWA adsorption increased on the cotton fabric with the wash cycles. Though adsorption of CC/DAS continuously increased up to the 20th cycle, that of DSBP increased sharply before the 10th cycle and reached an equilibrium. The whiteness of the fabrics dried in the shade was greater than that dried under the sunlight through window glass. The color change of dyed fabrics was increased by the number of wash cycles. Pink changed more greatly than blue, yellow or grey cloth. The color change(\Delta{E)}$ of dyed fabric washed repeatedly up to the 20th cycle with the detergent without FWA was less than 1. It is recommended to wash pale colored fabric with the detergent free of FWA.

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