• 제목/요약/키워드: Dispersing

검색결과 427건 처리시간 0.024초

Surface Modification of Ag Coated Cu Conductive Metal Powder for Conductive Silicone Sealant Gasket Paste

  • Park, Seong-Yong;Yoon, Tae-Won;Lee, Chung-Ho;Jeong, In-Bum;Hyun, Sang-Hoon
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.1076-1077
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    • 2006
  • Conductive pastes consist of conductive fillers( Au, Ag, Ni, Cu etc.), organic binders, solvents and additives. Meanwhile, there are some metal powders such as copper, nickel etc that are used for pastes which have serious surface corrosion problems. This problem leads to change of the color and decrease in conductivity and affect storage stability of conductive pastes. By using silane coupling agent and dispersion agent, we can ensure both the corrosion stability and long term storage stability, and enhance the high performance electrical and mechanical properties of EMI shielding silicone sealant.

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친수성 고분자와의 고체분산체로부터 질산펜티코나졸의 용출 증가 (Dissolution Enhancement of Fenticonazole Nitrate from Hydrophilic Polymer Solid Dispersions)

  • 김영일;김승인;최재윤
    • Journal of Pharmaceutical Investigation
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    • 제19권2호
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    • pp.109-116
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    • 1989
  • Solid dispersion of fenticonazole nitrate (FN) with poloxamer 407, polyethylene glycol 6000, povidone (K-90) were prepared by the solvent method. To characterize the state of the drug in solid dispersions, the x-ray diffractometry and differential scanning calorimetry were carried out. The identification of these systems suggested that FN in the poloxamer 407 system remained in crystalline state, and the drug in the PVP system was amorphous. A marked increase in the dissolution rate of FN was attained by dispersing the drug in the hydrophilic polymers used, and the dispersion with poloxamer 407 was superior to the other two carriers in releasing the drug into solution.

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Polyoxyethylene monooleate 및 oleyther계 유분산제의 제조와 Bunker B유의 분산효율에 미치는 영향 (Preparation of Oil dispersants using polyoxyethylene Monooleate and Oleyether and its Effect on dispersing efficiency to Bunker B Oil)

  • 염규설;강두환
    • 한국응용과학기술학회지
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    • 제12권1호
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    • pp.59-67
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    • 1995
  • Oil dispersants using polyoxyethylene monooleate, polyoxyethylene oleylether, and poly(oxypropylene-oxyethylene)glycol block copolymer were prepared, and oil dispersant efficiency was measured using vertical shaking flask method to 4 kinds of Bunker B oil with different physical properties by appling the prepared dispersants. Although the dispersant efficiency was differed according to the differences of physical properties of Bunker B oil, the dispersant prepared using polyoxyethylene oleylether was the most effective to disperse the oil into water. The impurities like surfur contained in sample oil have to be removed by filteration to obtain the correct degree of absorption using UV spectrophotometer.

2액형 폴리우레탄 도료에 관한 연구(II);폴리우레탄 도료의 제조와 도막물성 (2-Packaged Polyurethane Coatings(II);Preparation and Physical Properties of Polyurethane Coatings)

  • 김성길;정경택;박홍수
    • 한국응용과학기술학회지
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    • 제12권1호
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    • pp.19-27
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    • 1995
  • The 2-packaged polyurethane coatings were synthesized, blending pheylmodified polyesters(of which synthetic methods were reported in the previous paper), Desmodur L-75(polyisocyanate wide1y used for coatings), wetting-dispersing agent, white pigment. etc. A variety of coating properties were tested for the coating treatment polyurethane coationgs. Compared with conventional 2-packaged polyure-thane coating, abrasion resistance and lightness index difference of the ones synthesized in the present work were somewhat decreased, but the coating properties such as hardness, gloss specular, cross hatch adhesion. etc. were improved. Especially, resistance against chemical reagents and salt were strikingly improved. In addition. the coationgs had short drying time and long pot-life. This shows that the coationgs are appropriate for rapid drying coatings.

급성(急性) 후두염(喉頭炎)에 대(對)한 문헌적(文獻的) 고찰(考察) (A Literature Study on Acute Laryngitis)

  • 정창호;김윤희
    • 혜화의학회지
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    • 제14권1호
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    • pp.113-128
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    • 2005
  • 1. Acute laryngitis is a hoarse voice or the complete loss of the voice because of irritation to the vocal folds. 2. Acute laryngitis belongs with the GeupHuEum, HuBi, HuPung in oriental medicine. 3. GeupHuEum is caused by wind and cold, weak of lung and kidney, evil energy of liver, sore throat, etc. It is treated with the methods of cooling lung and wetting, removing heat and changing phlegm, etc. 4. Hubi is caused by fire and wind, dampness, large lung. It is treated with the methods of removing heat and antidote, reinforcing and descending fire, bleeding by acupuncture, vomiting. 5. Hupung is caused by phlegm and heat of lung and stomach, wind and heat. It is treated with the methods of dispersing wind and removing heat and changing phlegm by medicine, acupuncture, moxibustion, vomiting, fumigation.

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Characterization of Nonlinear Behaviors of CSCNT/Carbon Fiber-Reinforced Epoxy Laminates

  • Yokozeki, Tomohiro;Iwahori, Yutaka;Ishibashi, Masaru;Yanagisawa, Takashi
    • Advanced Composite Materials
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    • 제18권3호
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    • pp.251-264
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    • 2009
  • Nonlinear mechanical behaviors of unidirectional carbon fiber-reinforced plastic (CFRP) laminates using cup-stacked carbon nanotubes (CSCNTs) dispersed epoxy are evaluated and compared with those of CFRP laminates without CSCNTs. Off-axis compression tests are performed to obtain the stress-strain relations. One-parameter plasticity model is applied to characterize the nonlinear response of unidirectional laminates, and nonlinear behaviors of laminates with and without CSCNTs are compared. Clear improvement in stiffness of off-axis specimens by using CSCNTs is demonstrated, which is considered to contribute the enhancement of the longitudinal compressive strength of unidirectional laminates and compressive strength of multidirectional laminates. Finally, longitudinal compressive strengths are predicted based on a kink band model including the nonlinear responses in order to demonstrate the improvement in longitudinal strength of CFRP by dispersing CSCNTs.

매립지반의 팽이말뚝 평판재하시험 사례 연구 (Case Study Top-Base Foundation Static Loading Test in Reclaimed Land)

  • 신은철;김성환;이애영
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 추계 학술발표회
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    • pp.721-728
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    • 2008
  • Top-Base Method is a stabilization method for light weight structures particularly in the soft ground. It is widely used for the increment of bearing capacity and the effect of restraining settlement when the bearing capacity of the ground is not enough. Top-shaped cone concrete foundations are installed in graveled laid over soft ground. The principle of the basic method is to maximize effect of dispersing the overburden pressure by increasing the contact area of the top-shaped cone. Therefore, the bearing capacity is increased and the settlement is decreased by the embedded resistance of pile part in the ground. In this paper, the plate bearing test was conducted to evaluate the feasibility of Top-Base foundation. Based on the test results, the coefficient of subgrade reaction, elastic modulus, and settlement of foundation on reclaimed land was derived.

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Preparation and Characterization of Anionic Emulsified Asphalt with Enhanced Adhesion Properties

  • Lee, Eun-Kyoung
    • Elastomers and Composites
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    • 제50권4호
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    • pp.304-313
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    • 2015
  • In this study, the anionic emulsified asphalt was prepared by dispersing asphalt particles evenly into water with combination of anionic and nonionic surfactants. Effects of NaOH and $CaCl_2$ on the phase stability of the emulsified asphalt were also investigated through zeta potential value and rheology behavior; the emulsified asphalt added with NaOH and $CaCl_2$ showed higher zeta potential value than that the asphalt with addition of only anionic and nonionic surfactants. In addition, with regard to shear thinning behaviors, it was found that pH of the emulsified anionic asphalt and $Ca^{2+}$, counter ion, affected the phase stability. SBR (styrene-butadiene-rubber) latex, EPD (water dispersed Epoxy), PU (polyurethane) and RI-10S, SBS (styrene-butadiene-styrene)-based property improvement additive, were used and studied to enhance the adhesion properties with the aggregates. RI-10S, however, was found to be only compatible with the anionic emulsified asphalt; the coating rate, adhesion and compression strength were increased with the RI-10S content.

전륜 Insulator 이음 개선을 위한 강건 구조 방안 연구 (A Study On The Robust Structure For Improvement of Front Insulator Noise Improvement)

  • 이상종
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제17권3호
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    • pp.197-206
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    • 2017
  • Purpose: Clarify the cause of the noise by the front wheel strut insulator, which is located in close proximity to the driver's seat. Methods: The improvement mechanism was confirmed through failure analysis and reproduction test of the joint generation mechanism. In addition, the main factors were analyzed through principal test. Results: This paper describes the mechanism of occurrence of noise due to deterioration and hardness increase of rubber, deformation on severe road surface, foreign matter and water inflow in cold weather. Conclusion: We found that the insulator and body deformation can be minimized without increasing the thickness of the body and the insulator and reinforcing the body by dispersing the input load by applying load distribution structure instead of the local forming structure of the insulator in the insulator robust structure.

가격할인하 안전재고 합리화를 위한 분배시스템 운영에 관한 연구 (A Study on the Operation of Distribution System for the Rationalization of Safety Stock under the Price Discount)

  • 김병찬;김홍기
    • 산업경영시스템학회지
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    • 제32권4호
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    • pp.45-52
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    • 2009
  • The objective of this was to improve a transportation cost relation between Central Distribution Centers(CDCs) and Regional Distribution Centers(RDCs), to control inventory cost concerning safety stock for each service level, by reviewing distribution steps connecting CDCs and RDCs under the price discount. It was also to examine and compare operating costs for the following two alternative suggestions for setting the service standard as a counter measure for a stock-out of the distribution network system management. First, provision by dispersing the safety stock to the CDCs and RDCs; and second, exclusive provision of the safety stock only to the RDCs. The cost comparison analysis was made for each category of purchase costs, regular transportation costs, express transportation costs, and inventory holding costs.