• 제목/요약/키워드: Rheological properties

검색결과 1,369건 처리시간 0.033초

Effects of HLB value on oil-in-water emulsions: Droplet size, rheological behavior, zeta-potential, and creaming index

  • Hong, In Kwon;Kim, Su In;Lee, Seung Bum
    • Journal of Industrial and Engineering Chemistry
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    • 제67권
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    • pp.123-131
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    • 2018
  • Using mixed nonionic surfactants Span/Tween, we investigated the effects of HLB value on the O/W emulsion stability and rheological behaviors. In this study, MS-01 (Span 60 & Tween 60) and MS-02 (Span 80 & Tween 80) was used as mixed nonionic surfactants. We considered required HLB value 10.85 and selected corresponding HLB value range 8-13. The droplet size distributions, droplet morphology, rheological properties, zeta-potential and creaming index of the emulsion samples were obtained to understand the mechanism and interaction of droplets in O/W emulsion. The results indicated that optimal HLB number for O/W emulsions was 10.8 and 10.7, while using MS-01 surfactant and MS-02 surfactant respectively. MS-01 (HLB = 10.8) sample and MS-02 (HLB = 10.7) sample showed smallest droplet size and highest zeta-potential value. Rheological properties are measured to understand rheological behaviors of emulsion samples. All emulsion samples showed no phase separation until 30 days storage time at $25^{\circ}C$.

결합재의 유동특성 및 다짐에너지에 따른 포러스콘크리트의 특성에 관한 연구 (A Study on the Properties of Porous Concrete according to Rheological Property of Binder and Compaction Energy)

  • 이준;박승범;김정환;김범규;김형석
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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    • pp.596-599
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    • 2004
  • The purpose of this study is to investigate properties of porous concrete according to rheological properties of binder and compaction factor. The results of this study, the rheological property of binder is stabilized when a mixing time is over 240 seconds in case of target flow values are $175\%\;and\;200\%$. The void ratio of specimen has a very near value by target void ratio on the whole according as the rheological properties of binder and compaction energy are changed when target flow value is $200\%$, compaction energy is $75kN{\cdot}m/m^2$. The specimen has the excellent compressive strength when compaction energy and target flow value are $100kN{\cdot}m/m^2$ and $200\%$ respectively.

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Rheological, Morphological and Electrical Properties of Polycarbonate/Multi-walled Carbon Nanotube Composites

  • Han, Mi-Sun;Sung, Yu-Taek;Chung, Ji-Woong;Kim, Woo-Nyon;Lee, Heon-Sang;Kum, Chong-Ku
    • 한국고분자학회:학술대회논문집
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    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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    • pp.220-220
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    • 2006
  • Rheological and electrical properties of the polycarbonate (PC) / multi-walled carbon nanotube (MWNT) were studied. The MWNT was funtoinalized by treating with the hydrogen peroxide ($H_{2}O_{2}$). The electrical conductivity showed higher value for the PC/MWNT ($H_{2}O_{2}$ treated, freeze drying) composites compared that of the PC/MWNT ($H_{2}O_{2}$ treated, thermal drying) composites. From the results of the morphological, rheological, and electrical properties of the PC/MWNT composites, it is suggested that the electrical and rheological properties of the PC/MWNT composites are affected by the MWNT-MWNT network structure which is related with the MWNT morphologies such as the degree of aggregation and aspect ratio of the MWNT.

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파이넥스 슬래그 미분말을 혼합한 시멘트 페이스트의 유동특성 (Rheological Properties of Cement Pastes Blended Finex-Slag Powder)

  • 이근재;변승호;송종택
    • 한국세라믹학회지
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    • 제46권6호
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    • pp.657-661
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    • 2009
  • In this study, rheological properties of cement pastes containing ground Finex-slag (4000, 6000, 7000 c$m^2$/g) were investigated bymini-flow test and coaxial cylinder viscometer. And also blast furnace slag(4000, 6000, 7000 c$m^2$/g) were used for comparison. According to the experimental results, Finex-slag and blast furnace slag showed very similar trend in the rheological properties of the cement pastes. The fluidity of cement pastes blended Finex-slag and blast furnace slag powder were improved by high replacement ratio. In the relationship of plastic viscosity and yield stress appeared the tendency of the proportion greatly. And in the relationship of plastic viscosity, yield stress and mini-flow appeared the tendency of the inverse proportion.

찰흑미분을 첨가한 밀가루 반죽의 물리적 특성에 관한 연구 (A Study of Rheological Properties of Dough with Waxy Black Rice Flour)

  • 김원모;김태형;이윤신
    • 한국조리학회지
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    • 제12권4호
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    • pp.236-246
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    • 2006
  • The different rheological properties of wheat flour and waxy black rice flour dough were investigated in dough with 10, 20, 30 and 40% of waxy black rice flour(WBRF). Water absorption and weakness of dough was increased, but stability of dough, high initial pasting temperature, viscosity at peak point and the volume were decreased after 2nd fermentation as the addition of WBRF was increased. In the 10% addition of WBRF, the dough showed similar rheological properties with those of control group.

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이성분 혼합응고제에 의한 두부의 물성 변화 (Effect of Mixed Coagulant on the Rheological Properties of Soybean Curd)

  • 홍정화;김진우;이재권
    • 한국식품영양과학회지
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    • 제26권6호
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    • pp.1096-1101
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    • 1997
  • Soy curd was prepared using imported soybean(U.S.grade A) and changes in quality were evaluated using different types and mixtures of coagulants(CaCl$_2$, CaSO$_4$, MgCl$_2$, MgSO$_4$, and glucono-$\delta$-lactone). Quality of soy curd was determined by rheological properties, yield, and color. Based upon the characteristics of each coagulant, mixtures of two coagulants were prepared in various ratios. The mixture of CaSO$_4$or MgCl$_2$with glucono-$\delta$-lactone(GDL), and that of CaSO$_4$or MgCl$_2$with MgSO$_4$resulted in soy curd of good quality in terms of rheological properties and yield.

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Rheological properties of arabinogalactan solutions related to the carbohydrate composition of different legumes

  • Kyeongyee Kim;Choon Young Kim
    • 한국식품저장유통학회지
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    • 제30권5호
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    • pp.785-796
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    • 2023
  • The aim of this study was to elucidate chemical structures and rheological properties of arabinogalactans (AGs) isolated from three legumes including black gram (BG), great northern bean (GNB), and California small white bean (CSWB). The ratio of galactose to arabinose (G/A) in three legumes increased in the order of BG > GNB > CSWB. The rheological measurements of 1-5% (w/v) AG solutions revealed Newtonian and non-Newtonian flow behaviors. BG exhibited yield stress, indicating plastic behavior. Small-amplitude oscillatory tests indicated viscoelastic properties of BG, GNB, and CSWB ranging from solid-like, paste-like, and liquid-like behaviors, respectively. Small-strain oscillatory tests were conducted to assess the structure recovery of the AGs after pre-shearing. G" values of BG and GNB increased, but those of CSWB remained constant after shearing. These results suggest that the chemical structures of the AGs, particularly their G/A ratios, influence their rheological properties.

비 뉴톤 유동 메카니즘에서 틱소트로피 식과 유변 파라메타 (Thixotropic Equation and Rheological Parameters on Non-Newtonian Flow Mechanism)

  • 김남정
    • 한국응용과학기술학회지
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    • 제32권3호
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    • pp.386-393
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    • 2015
  • 콜로이드 분산계와 같은 복잡한 물질의 유변성질은 전단 흐름이 일어날 때 비뉴톤 유동현상을 나타낸다. 이들 유변성질은 유동단위의 성질과 유동 세그먼트 사이의 상호작용에 의하여 영향을 받는다. 유동곡선을 이론적인 틱소트로피식에 적용하여 여러 틱소트로피 유동 곡선에 대한 유동파라메타, 완화시간, $({\beta}_2)_0$, 구조적인 요인, $C_2$, 전단 모듈러스, $X_2/{\alpha}_2$을 구하였다. 유변 파라메타의 변화는 비뉴톤 유동, 점도, 유동 세그먼트의 유동 활성화 에너지와 직접적인 관계가 있다.

수지의 함량 변화에 따른 잉크 비히클의 유변학적 특성에 관한 연구 (A Study for The Effect of Variation of Resin Content on The Rheological Characteristics of Ink Vehicle)

  • 방종관;김성빈;김태환;이규일
    • 한국인쇄학회지
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    • 제23권2호
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    • pp.117-128
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    • 2005
  • Printing inks are basically dispersions of solid pigment particles in a vehicle. Pigment flocculation and/or colloidal aggregates created by thixotrope additives form a three- dimensional network in the inks. This structure complicates the flow behaviour of inks. However, if the internal structure is formed under control, the printing process will benefit from it because the ink must satify rheological requirements over a very wide range of shear conditions. The presence of internal structure results in the following prominent non-Newtonian rheological properties: viscoelasticity, yield stress, shear thinning and thixotropy. If the components of printing inks were changed, the rheological characteristics such as viscosity, yield stress, viscoelasticity and tack value were considerably varied. Thus, in this paper, the effects of changing the content of rosin modified phenolic resin on rheological properties of the vehicle will be studied. For that, the rheological properties were found by flow, yield stress, creep and oscillation measurements using Bohlin C-VOR Rotational Rheometer. And Emulsion rheology and its microstructure will be investigated.

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경량 기포 콘크리트의 레올로지 특성이 소포억제에 미치는 영향 (Influence of Rheological Properties of Lightweight Foamed Concrete on Preventing Foam Collapse)

  • 이향선;전종운;조무진;기성훈;한동엽
    • 한국건설순환자원학회논문집
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    • 제6권4호
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    • pp.304-310
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    • 2018
  • 본 연구에서는 경량 기포 콘크리트의 부피 안정성을 확보하기 위해 소포를 저감시킬 수 있는 요소들을 레올로지 특성을 연계하여 분석하였다. 실험계획으로는 비빔시간, 물-결합재비, 증점제, 기포제, 폐지 첨가량에 대한 변화로 각 요인을 통해 실험하였다. 먼저 과도한 비빔과 기포제의 첨가량에 의해 발생한 다량은 기포는 슬러리 내에서 불안정한 상태로 존재하여 침하를 발생시킨다. 특히 기포제의 경우 계면활성제로써 물에 영향을 미치므로 배합 계획 시 물에 대한 질량비로 계획해야할 것으로 판단된다. 또한 레올로지 특성을 통해 경량 기포 콘크리트의 소성점도와 소포량이 반비례관계를 가진 것을 확인할 수 있었다. 따라서 본 연구의 결과는 경량 기포 콘크리트의 소포를 저감시킬 수 있는 요소들을 분석함으로써 경량 기포 콘크리트의 배합 조건에 대한 기초적인 자료를 제공될 것으로 판단된다.