• 제목/요약/키워드: Viscose

검색결과 86건 처리시간 0.021초

일축 진동형 금속제진장치 형상 최적설계 (Shape Optimization of Uniaxial Vibrating Metal Damper)

  • 윤지훈;박지운;임윤묵;윤길호
    • 한국전산구조공학회논문집
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    • 제30권4호
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    • pp.313-318
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    • 2017
  • 본 연구는 진동에너지를 흡수하기 위한 진동 금속 댐퍼의 구조 해석과 최적 설계를 수행한다. 고무 베어링, 마찰 또는 점성 댐퍼와 같은 다른 댐퍼와는 달리 이 금속제진장는 금속의 소성 변형과 그에 따른 히스테리시스 현상을 이용하여 구조물의 진동을 감소시킨다. 이 금속제진장치를 최적화 하려면 댐퍼를 통해 소성 변형을 얻는 것이 중요하다. 금속제진장치의 최적화된 형상을 찾기 위해 형상 최적화 방법을 적용하였다. 또한 매개 변수화 체계에 따라 일부 최적의 모양을 찾을 수 있다.

Surface and Adsorption Properties of Activated Carbon Fabric Prepared from Cellulosic Polymer: Mixed Activation Method

  • Bhati, Surendra;Mahur, J.S.;Dixit, Savita;Choubey, O.N.
    • Bulletin of the Korean Chemical Society
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    • 제34권2호
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    • pp.569-573
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    • 2013
  • In this study, activated carbon fabric was prepared from a cellulose-based polymer (viscose rayon) via a combination of physical and chemical activation (mixed activation) processes by means of $CO_2$ as a gasifying agent and surface and adsorption properties were evaluated. Experiments were performed to investigate the consequence of activation temperature (750, 800, 850 and $925^{\circ}C$), activation time (15, 30, 45 and 60 minutes) and $CO_2$ flow rate (100, 200, 300 and 400 mL/min) on the surface and adsorption properties of ACF. The nitrogen adsorption isotherm at 77 K was measured and used for the determination of surface area, total pore volume, micropore volume, mesopore volume and pore size distribution using BET, t-plot, DR, BJH and DFT methods, respectively. It was observed that BET surface area and TPV increase with rising activation temperature and time due to the formation of new pores and the alteration of micropores into mesopores. It was also found that activation temperature dominantly affects the surface properties of ACF. The adsorption of iodine and $CCl_4$ onto ACF was investigated and both were found to correlate with surface area.

형태안정성 레이온 복합소재의 염색특성에 관한 연구

  • 김명순;박성민;권일준;서말용;김혜정
    • 한국염색가공학회:학술대회논문집
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    • 한국염색가공학회 2011년도 제45차 학술발표회
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    • pp.61-61
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    • 2011
  • 비스코스 레이온(Viscose Rayon)은 목재 펄프를 원료로 한 재생섬유로서 은은한 광택과 발색성, 흡습성 등의 기능 뿐만 아니라, 천연섬유에 찾을 수 없는 Numeri감(Smoothness), Drape(처짐)성, 반발탄성을 가지고 있는 지극히 친환경적이며 자연순환형 소재로 인식, 지구온난화에 따른 CoolBiz Look 패션소재인 레이온 소재에 관심이 증대되고 있다. 한편, 레이온 소재는 수분흡수 시 강도저하, 수축과 구김, 염색 불균염 등의 문제점과 섬유공정상 생활취급상에 많은 애로를 가지고 있으며, 구성고분자가 수소결합에 의해 강고하여 "신축문제", 수분흡수시 팽윤(Swelling)에 의한 형태불안, 즉 "수축문제"가 개선해야 할 고질적 문제로 남아 있다. 또한, 습식방사에 따른 분자구조적 불안정성으로 건 습열처리시 형태불안정(치수변화율이 큼)으로 제직(준비) 및 후공정상 여러 가지 Trouble 유발과 완제품 세탁시 수축발생으로 종종 Dry Creanning해야 하는 문제점들이 내재되어 있다. 따라서 본 연구에서는 레이온 소재의 형태안정화 제품을 개발하기 위하여 복합사가공 및 염색가공 기술을 개발하고자 하며, 신축 및 복합기술에 의한 Rayon DTY, T/R 신축 및 복합기술에 의한 Rayon DTY, T/R 복합가공사를 개발, 제편직 요소기술과 최적의 전처리 조건, 다양한 염료의 종류, 염색온도 조건 등에 관한 연구를 진행하였다.

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Rayon-like 섬유의 최적 방사 조건 (Optimum Condition of Spinning for Rayon-like Yarn)

  • 안영무
    • 패션비즈니스
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    • 제12권1호
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    • pp.120-128
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    • 2008
  • Rayon fiber as clothing material has silk-like property which relates to other synthetic fibers. It has many advantages that is required to women's clothes. However rayon has many shortcomings. Therefore this research is to spin rayon-like polyester which has high contraction property to be synthesized by previous research to solve those shortcomings and to maintain advantages of rayon. The contraction ratio of regular polyester is 30% and the contraction ratio of this synthesized polyester is over 60%. The spinning temperature of regular polyester ranges from $285^{\circ}C$ to $300^{\circ}C$. However, this copolymer is set range from $270^{\circ}C$ to $290^{\circ}C$, which is $10^{\circ}C$ less than regular polyester due to decreasing melting temperature. The spinning velocity effects the tensile strength and elongation of yarn magnificently. The high velocity of spinning makes yarn highly oriented, increases the tensile strength and decreases the elongation. This research defines the condition as following; draw ratio 2.734, First roller temperature $85^{\circ}C$, Slit heater temperature $175^{\circ}C$.

기능성 쌀가루 혼합분의 제빵 적성 (Studies on Bread-Making Quality of Bread Mixed with Wheat Flour and Several Functional Rice Flour)

  • 유경아;강미영
    • 한국식생활문화학회지
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    • 제20권3호
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    • pp.299-304
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    • 2005
  • This study investigated the feasibility of the bread making process with the mixture of the functional rice flour. The bread was manufactured with 20, 30 or 40% functional rice flour with increasing and wheat flour. Gelatinization characteristics of the rice starch was examined by differential scanning calorimetry(DSC). Coated with soluble dietary fiber rice showed the highest gelatinization enthalphy among functional rices and other functional rices were similar to normal rice. in the viscosity point of view. generally the viscosity related to the addition ratio. The most viscose case was 30% Sangwhang rice but in fermented with monascus ruber rice case, viscosity was low even with 40% case because of the transformation of the starch granules. In sensory evaluation, the highest sensory scores for the uniformity of pore size and flavor were obtained when sangwhang rice flour content was 20%. The textual study was mainly focused on the hardness, cohesiveness, adhesiveness, springiness, chewiness. Textural characteristics of functional rice bread crumb bakedwith 20% coated with soluble dietary fiber rice, 20% sangwhang was low in hardness, chewiness and gumminess. Therefore, Sangwhang rice flour 20%, Monascous ruber 20% and Coated soluble dietary fiber rice 20% were considered to be the most suitable addition ratio for the rice breads.

Dyeproperties of Artificial silk/paper mulberry mixed fabrics using Dendropanax morbifera Lev.

  • Jeon, Ji-Eun;Jeon, Jin-Hwa;Lee, Sang-A;Choi, Jae-Hong;Park, Young-Mi
    • 한국염색가공학회:학술대회논문집
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    • 한국염색가공학회 2011년도 제45차 학술발표회
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    • pp.33-33
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    • 2011
  • Artificial silk that called "Ponggi (Gyeongsangbukdo, Korea) In-Gyeun" in Korea is entirely viscose rayon of which made main component refined larches and cotton linter. It also is natural fabrics with light weight, cool texture, free from the body and well ventilation property, so, feel good touch during the wearing. In addition, it often used as summer cloth and bedding because it has good absorbancy to perspiration and antistatic. The "Hanji", made of paper mulberry, is known as useful material for human. In this research focused on dyeability of Artificial silk/paper mulberry mixed fabrics using Dendropanax morbifera Lev.(called as "Hwangchil") Especially, the results were in comparison to the dyeing properties of Hwangchil with liquid/solid fermentation or not. As the results, The ${\Delta}E$ difference was dominated when the fabric dyed with fermentation by solid state at $60^{\circ}C$. And it was confirmed that the pH of fermented dye had an important influence in the coloration.

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반사방지 나노구조의 성형성과 광학적 특성에 대한 이형 온도의 영향 (Effects of Demolding Temperature on Formability and Optical Properties of Anti-reflective Nanostructure)

  • 여나은;심영보;조상욱;김두인;김기남;장경수;정명영
    • 마이크로전자및패키징학회지
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    • 제23권2호
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    • pp.91-96
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    • 2016
  • 본에서는 저반사 나노구조 필름의 열 나노임프린트 공정 최적화를 위해 나노구조의 성형성과 광학적 특성에 대한 이형 온도의 영향을 평가하였다. 이형 온도에 따른 광학적 특성을 평가한 결과 $70^{\circ}C$까지는 이형 온도가 증가함에 따라 투과율과 반사율 특성이 향상되는 거동을 보였으나 그 이후에는 오히려 투과율이 감소하고 반사율이 증가하는 경향을 보였다. 이와 같은 이형온도에 따른 거동은 성형성에도 유사하게 관찰되었으며 자유체적 형성과 고분자 유동에 의한 것으로 보인다. 따라서, 이형 온도에 따라 고분자의 유동과 자유체적의 형성에 의한 패턴의 성형성이 결정되며, 이로 인해 광학적 특성에 영향을 줄 수 있음을 확인하였다.

접착심지에 관한 연구 (Studies on Adhesive Nonwovenfabrics for Padding Cloths)

  • 성화경
    • 대한가정학회지
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    • 제11권3호
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    • pp.276-284
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    • 1973
  • An experiment, aimed at finding out the adhesive condition when adhesive non-woven fabrics for padding cloths are used for padding cloths of blouse, has been conducted. Materials used were three different kinds-scoured, sanforized, and permanent pressed- of combined fabrics of polyester and cotton. As for padding cloth material, mixed spinning nonwoven fabrics of polyster and viscose rayon have been used. Adhesive conditions were made each at $120^{\circ}C$, $140^{\circ}C$, $160^{\circ}C$ and $180^{\circ}C$, respectively, and adhesive time has been limited to 5, 10, 20, 30, 40 seconds each. External appearance as well as quality have been watched through washing experiment. In case of 12$0^{\circ}C$, all experimental materials were separated at the seventh washing and as for $140^{\circ}C$, all but the material which has been attached on scoured cloth for 40 seconds were separated. In case of 20 seconds only permanent pressed cloth and sanforized cloth were separated. At 30 and 40 seconds, the adhesive conditions have been maintained up to the seventh washing. In case of 5 seconds $180^{\circ}C$it was not turned yellow, but all were separated. In case of 10, 20, 30 and 40 seconds, at above temperature all were turned yellow in the adhesive process. Therefore, the adhesive power could be said strong enough, though it was not very practical. In this experiment, the lower the temperature of iron is, the longer time it has to be touched. At higher temperature however, relatively short time makesn it possible for adhesion and depending upon the finishing methode of cloth, there is slight difference in adhesive power. As a result, the best adhesive condition for all experimental materials is $160^{\circ}C$of iron temperature, and the time of adhesion is between 30 and 40 seconds.

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적송수피 색소 성분의 화학적 조성과 섬유 염색성 (Dyeabilities with Various Fabrics and Chemical Composition of Brown Colorants from Pine Bark)

  • 김용숙;배순이
    • 한국의류산업학회지
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    • 제15권1호
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    • pp.138-146
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    • 2013
  • Chemical compositions and biological functions of brown colorants extracted from pine bark(Pinus densiflora) have been studied. Dyeing test using multifiber fabrics with extracted colorants were preliminary carried out. Dyeing conditions and fastness tests of selected fabrics have been also studied. The brown colorants were produced 1.5% concentrations by solvent extraction from milled pine bark using methanol. The colorants were extracted with 80% methanol as best choice by a criteria of solid quantity and dyeability on fabrics. The chemical compositions were identified as mixtures of taxifolin epicatechin and procyanidin by LC/MS analysis. The brown colorants could be dyed not only natural fibers such as cotton, silk and wool but also synthetic fiber as nylon and semi-synthetic fiber as viscose rayon. Maximum K/S values was shown at 400 nm according to different fiber with color appearance of redish brown. Optimum pH and temperature of dyeing conditions was 4 and above $80^{\circ}C$, respectively. The brown colorants had a strong antioxidant activity compared to Butylated hydroxyanisole as standard and weak antimicrobial activity against E. coli. compared to kanamycin. Washing, rubbing, perspiration, dry cleaning and light fastness for cotton, nylon and silk dyed with the brown colorants were carried out by KS K method. Most of color fastness such as washing, rubbing, perspiration, and dry cleaning were represented as 4-5 grade. However, light fastness was reported as 2-3 grade. From this studies, brown colorants produced pine bark have a high potentials for natural dyeing on fabrics with antioxidant activity.

Durable Press 가공된 레이온직물의 물성변화에 관한 연구 (A Study on the Physical Properties of Durable Press Finished Rayon Fabrics)

  • 김희숙;김은애
    • 한국의류학회지
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    • 제11권3호
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    • pp.57-65
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    • 1987
  • The purpose of this study was to investigate the optimum treatment [condition for the Durable press finish of viscose rayon fabrics. Three types of commercial N-methylol crosslinking agents were applied to the fabric utilizing the pad-dry-cure technique. Changes in physical properties were evaluated for the various resin and catalyst concentrations. For DMU, the effect of different catalysts, $MgCl_2$ and $NH_4Cl$, were also compared. DMU treated fabrics showed in crease recovery angle, tensile strength and tearing strength but drastic decrease in abrasion resistance. DMDHEU and MDMDHEU treated fabrics were similar in most physical properties. However, DMDHEU treated fabrics were better in crease recovery angle and stiffness, and MDMDHEU treated fabrics were better in tensile strength, tearing strength and abrasion resistance. For a given resin system, crease recovery angle, tensile strength and stiffness increased with a increase in resin concentration. Tearing strength showed very little change, while abrasion resistance was decreased significantly as the crease recovery angle was increased. For the treatment of DMU, $MgCl_2$ catalyst was much better than $NH_4Cl$ in all physical properties. When $NH_4Cl$ catalyst was used, strength reduction and discoloration were observed. As the catalyst concentration increased, crease recovery angle, stiffness were increased. Tensile strength and tearing strength were increcased than control but at high catalyst concentration, the strength were decreased and abrasion resistance was significantly lowered. DMDHEU and MDMDHEU were more sensitive to catalyst concentrations than DMU.

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