• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2005년도 추계 학술대회논문집
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• pp.31-34
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• 2005

This article has investigated the spatial distribution of the solid particles in polymerization reactors using CFD analysis (FLUENT v. 6.2.1). The suspension of the solids in stirred reactors is affected by a number of parameters including particle diameter, vessel shape, impeller size, impeller speed, and rotating direction of stirrer. The degree of solids suspension in the vessel was quantified with a statistical average value, ${\sigma}^2$. The best stirring conditions were determined based on ${\sigma}^2$, which was found to depend on the vessel bottom shape.

• 한국토양환경학회지
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• 제2권3호
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• pp.23-30
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• 1997

본 연구의 목적은 슬러리상 생물반응기를 이용한 석유계탄화수소 오염토양의 처리에 있어서 고형물함량 및 혼합강도의 영향을 평가하는 것이다. 디이젤오염토양의 슬러리상 생물학적 처리에 대한 수행결과는 실험실규모에서 얻어졌고 TPH(총 석유계탄화수소)는 생물학적 처리와 연관하여 평가되었다. TPH의 생물학적 및 비생물학적 거동은 디이젤내의 화합물에 의해 이전에 노출되지 않은 토양을 이용하여 결정되었다. 투입량에 대한 반응기부피는 고형물함량을 최대화함으로써 줄여질 수 있다. 고형물함량 50% 및 20%를 적용한 결과 생물학적 TPH 제거율에 있어서 약간의 차이(57.5%:61.6%)를 보여주었다. 혼합과 토양입자의 부유는 오염물의 탈착 및 생물학적 분해에 있어서 매우 중요하다. 이러한 관점에서 본 연구는 두가지 혼합강도를 이용하여 수행되었다. 70rpm을 이용한 반응기의 경우 20rpm을 적용한 반응기에 비하여 토양입자의 부유 및 TPH의 제거율에 있어서 더 좋은 결과를 나타내었다. 20rpm을 적용한 반응기의 경우 토양입자의 완전한 부유가 일어나지 않았다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.745-749
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• 2011

혼합용 임펠러를 장착한 연료탱크의 액체연료와 미세 고체입자의 부유, 혼합 현상을 분석하고자 2차원 혼합 유동 수치해석을 수행하였다. 다상 유동해석은 Eulerian Grandular Multiphase 기법을 사용하였고, 해석기법을 12vol% 고체 혼합 조건 실험의 축방향 고체 농도 분포와 비교하여 확인하였다. 해석용 연료탱크는 10.5vol% 고체입자를 액체연료와 혼합하는 것으로 회전수 700rpm 조건에서 4가지 경우의 임펠러 위치와 유속 조건으로 해석을 수행하였다. 각 경우에 대한 Quality of Suspension 결과를 비교하여 적합한 임펠러 위치와 속도방향을 확인하였다.

• 현장농수산연구지
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• 제23권2호
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• pp.33-41
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• 2021

The effect of homogenization treatment on the suspension stability of makgeolli was evaluated. The non-soluble solids of makgeolli that were not homogenized were precipitated at 1.0-68 mm after 10 minutes of standing and 2.0-70.5 mm after 30 minutes of standing. On the other hand, in the makgeolli homogenized with a blender for more than 20 seconds, no precipitated non-soluble solids were observed during the initial 10 minutes, and when it was left still for 30 minutes, it showed precipitation of 2.0 mm (control 58.0 mm). The makgeolli treated with a high-pressure homogenizer did not show any sedimentation until 30 minutes of standing. In the sensory evaluation, the high-pressure homogenized makgeolli had a score of 3.93, whereas non-treated had a score of 2.80, which was improved by 40% by homogenization.

• 한국식품과학회지
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• 제25권5호
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• pp.589-591
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• 1993

3가지의 다당류 분해효소를 사용한 가수분해가 미역추출액의 상징액율, 고형분 수율, 점도에 미치는 영향을 조사하였다. 그 결과 추출전에 효소분해할 때 고형분 농도를 27.31%, 고형분 수율을 14.04%까지 증가시켰다. 그러나 미역 분산액을 원심분리 후의 상징액율은 약간 낮았다. 추출액의 점도는 효소분해 초기에 유의적으로 증가하였다.

• Journal of Mechanical Science and Technology
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• 제14권10호
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• pp.1159-1167
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• 2000

Particles in liquid-solid suspension flow might enhance or suppress the rate of heat transfer and turbulence depending on their size and concentration. The heat transfer characteristics of liquid-solid suspension in turbulent flow are not well understood due to the complexibility of interaction between solid particles and turbulence of the carrier fluid. In this study, the heat transfer coefficients of liquid-solid mixtures are investigated using a double pipe heat exchanger with suspension flows in the inner pipe. Experiments are carried out using spherical fly ash particles with mass median diameter ranging from 4 to $78{\mu}m$. The volume concentration of solids in the slurry ranged from 0 to 50% and Reynolds number ranged from 4,000 to 11,000. The heat transfer coefficient of liquid-solid suspension to water flow is found to increase with decreasing particle diameter. The heat transfer coefficient increases with particle volume concentration exhibiting the highest heat transfer enhancement at the 3% solid volume concentration and then gradually decreases. A correlation for heat transfer to liquid-solid flows in a horizontal pipe is presented.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1992년도 가을학술발표회 논문집
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• pp.65-68
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• 1992

In characterizing a suspension, heterogenety is included onto the previous characterization using solids concentrations and flocculent characteristics, because of its importance in hydrodynamics. The mechanism of interface formation during the sedimentation of concentrated suspension (thickening) is investigated from a microcosm consisting of four particles in a same plane and a smaller particle below. The critical distances after shich interface forms are calculated as a function of particle size ratio when the small particle is located in the middle of the squre datermined by the large particles. The results shows that the critical separation distance increase as the size ratio approaches to one (homogeneous suspension). This conforms to the trend of existing observations that homogeneous suspensions create the solid-liquid interface at much lower concentration (at al larger separation distance) that the heterogeneous suspensions.

• 한국세라믹학회지
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• 제41권9호
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• pp.647-652
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• 2004

In aqueous tape casting of alumina slurry systems, the relationships between the suspension compositions and the defects of the dried tapes were discussed. The suspensions compositions were controlled with the ratios of the solids, water and organics binder contents. The effects of the thickness of dried tape and kinds of binder system were also examined. In the defect free region, the apparent viscosity showed nearly same value due to the count balancing effect of solid and organic binder content on the apparent viscosity. When water content was constant, increasing solid led to decrease of organic binder content. The defect free region was narrowed with increasing of casting thickness. When linear type acrylic emulsion binders system (D1000 and D 1035) were used, defect free zone formed the belt type in the triangle of solid, water and organic binder content according to the line of constant water contents. However the defect free region was not found in the cross-link type emulsion binder system (D 1050).

• Current Research on Agriculture and Life Sciences
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• 제32권4호
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• pp.211-214
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• 2014

본 연구는 액체에 현탁한 화분을 이용한 인공수분방법이 농촌의 노동력 절감과 '후지' 사과의 결실 및 과실품질에 미치는 영향을 구명하고자 실시하였다. 액체현탁화분의 화분발아율은 6시간 경과시까지 fructose 20% 용액에서 화분발아율을 20%수준으로 다른 용액에 비하여 낮은 발아율 유지하여 화분을 안정적으로 보존해 주었다. 인공수분 처리에 따른 정화아의 중심과 착과는 화분현탁액 65 g (/20 L), 무처리, 면봉 및 인공수분기(러브터치) 처리구들이 정상적인 결실을 보였다. 수확시 과실품질은 과형지수, 경도, 가용성 고형물 함량 및 산함량은 차이를 나타내지 않았다. 노동력절감은 액체현탁화분 처리가 면봉처리에 비하여 3.56배 감소한 결과를 보여 경영비를 줄이는데 우수한 효과를 보였다.

• Korea-Australia Rheology Journal
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• 제15권1호
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• pp.9-17
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• 2003

The rheological behaviour of anatase $TiO_2$ with organic coating has been investigated extensively in this study. The yield stress was measured over a wide range of solids concentration and pH using stress-controlled and speed-controlled rheometers. The organic treatment leads to a shift of the isoelectric point (IEP) from around pH 5.5 to pH 2.4. A maximum yield stress occurs in the vicinity of the isoelectric point determined by electrokinetic measurements. The transition of rheological behaviour between elastic solid and viscous liquid is represented by a stress plateau in a plot of stress against strain. It is hypothesised that the slope of the stress plateau reflects the uniformity of the structure, and hence the distribution of bond strength. Altering the concentration and the surface chemistry can vary the bond strength and its distribution. therefore, resulting in different type of failure: "ductile-type" or "brittle-type". pH and volume fraction dependence of yield stress could be described quantitatively using existing models with reasonable agreement.easonable agreement.