• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.48-54
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• 1986

Influencing factors on the instant properties of agglomerated parched barley powder prepared by fluidized bed agglomerator were investigated. Instant effect was measured by the determination of wettability, sinkability, dispersibility and solubility of agglomerated particles. Instant effect of agglomerated particle was influenced by sorts of binding materials, concentration of aqueous binder solution and agglomerated particle diameter. The binding materials for agglomerated process were water and aqueous solution of glucose, maltose and gelatin. Instant effect of agglomerated particles increased as the concentration of aqueous sugar solution increased. However, the effect of aqueous solution of gelatin on instant effect was inversely proportional to the concentration. The size of agglomerated particle had an outstanding effect on instant properties and the diameter of agglomerated particle ranging from 0.1 mm - 0.3 mm showed the excellent instant effect.

• Polymer(Korea)
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• v.34 no.1
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• pp.38-44
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• 2010

Core-shell particles of inorganic/organic pair were synthesized from $CaCO_3$ absorbed sodium dodecyl benzene sulfonate(SDBS) surfactant. Shell components were synthesized by sequential emulsion polymerization. Various monomers were used as shell components such as methyl methacrylate(MMA), ethyl acrylate(EA), butyl acrylate(BA), and styrene(St). Ammonium persulfate(APS) was used as an initiator and 2-ethylhexyl acylate(2-EHA) was used as a functional monomer, In the $CaCO_3$/organic core-shell particle polymerization, $CaCO_3$ absorbed surfactant SDBS of 0.5 wt% was prepared first and then core $CaCO_3$ was encapsulated by emulsion polymerization. 0.1 wt% of APS was added sequentially to minimize the formation of new monomer particle during shell polymerization. The structure of inorganic/organic core-shell particles were characterized by measuring the decomposition degree of $CaCO_3$ using HCl solution, thermogravimetric analyzer, scanning electron microscope, and transmission electron microscope.

• Proceedings of KOSOMES biannual meeting
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• 2009.06a
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• pp.131-132
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• 2009

마산만을 대상으로 하여 연안환경 중의 PAHs의 거동을 STELLA프로그램을 이용하여 파악하였다. 상태변수로는 용존 PAHs, 부유입자물질 중의 PAHs, 식물플랑크톤 내의 PAHs, 저질중의 PAHs 둥을 고려하였다. 화학적, 생물학적 과정으로는 용존 PAHs에서 광분해, 부유입자물질에서 흡착과 탈착, 식물플랑크톤에 의한 흡수 및 분비와 퇴적물로의 침강을 고려하였다. STELLA 프로그램을 이용하여 모델을 재현하였으며, 민감도 분석을 시행하였다. 또한 하천 및 대기로부터의 유입부하변동에 따른 현상황을 시나리오를 구성하여 시행하였다.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.437-440
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• 2006

Particle suspension is frequently observed in many natural flows such as in the atmosphere and the ocean as well as in various engineering flows. Recently, airborne micro or nano-scale particles in atmosphere attract much attention from environmental society since small particle cause serious environmental problems in the industrialized areas. Also, the characteristics of such heavy particles' behavior is quite different from its fluid particles because the inertia force and buoyance force acting on the heavy particles are different than those acting on fluid particles. Therefore, our studies is to investigate the characteristics of the behavior of heavy particles considering the inertia effect with or without gravity effect, but do not consider modification of turbulence by the particles, that is one-way interaction. We carried out direct numerical simulation of isotropic turbulence with particles under the Stokes drag assumption for a spherical particle. These results can be used in the development of a stochastic model for predicting particle's behavior.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2396-2400
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• 2008

The motion of small heavy particles in homogeneous isotropic turbulence in the present of gravity is investigated using Direct Numerical Simulations (DNS) at moderate Reynolds number. The Lagrangian velocity and acceleration statistics of particles and of flow for a wide range of Stokes number, defined as the ratio of the particle response time to Kolmogorov time scale of turbulence, were obtained for the direction of the gravity and normal direction, respectively. It is found that particles lose their correction faster than the case without gravity. Then, a significant increase in the average settling velocity was observed for a certain range of Stokes number. Our focus is placed on gravitational effect on very small particles. Our simulations show that as the Stokes number reduces to zero, their mean settling velocity approaches the terminal velocity in still fluid.

• Environmental engineer
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• s.324
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• pp.86-93
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• 2013

본 발명은 녹색 건축물에 적용되는 중수도 설치를 위한 수처리 시스템에 관한 것으로서, 더욱 상세하게는 건축물에서 배출되는 오수의 유입량을 제어하면서, 산기장치를 이용하여 상기 오수에 일정량의 에어를 공급하여 슬러지의 침강과 부패방지를 유도하는 유량조정조와, 상기 유량조정조를 거친 오수를 응집 및 침전처리하고 가압부상에의해 슬러지를 처리하는 가압부상조와, 상기 가압부상조를 거친 오수에 포함되어 있는 질소, 인을 처리하는 무산소조와, 상기 무산소조를 거친 오수에 포함되어 있는 유기물을 수처리용 접촉 메디아(DSBB)에 의해 분해하는 생물막조와, 상기 생물막조를 거친 오수를 침전과정을 통해 침전된 슬러지를 외부로 배출하는 침전조와, 상기 침전조를 거친 오수를 분리막에 통과시켜 오수에 포함되어 있는 미생물, 세균등의 미세입자들을 제거하는 분리막조와, 상기 분리막조를 거친 오수에 포함되어 있는 미처리 미세입자를 여과기에 통과시켜 처리하는 여과조와, 상기 여과조를 거친 오수를 오존($O_3$) 또는 UV 살균 처리하는 소독조와, 상기 소독조를 거쳐 최종적으로 처리된 처리수를 일정시간 동안 체류시켰다가 건축물의 중수로 재이용하기 위해 방출시키는 저수조를 포함하여 이루어지는 녹색 건축물에 적용되는 중수도 설치를 위한 수처리 시스템에 관한 것이다.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.4
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• pp.210-218
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• 2016

The pollutant removal efficiencies of stormwater runoff by settling were analyzed using field samples collected in 4 different raining events in a test bed installed in the Gwanpyung-Cheon stream in Daejeon. A 1.8 m high with 30 cm diameter cylindrical settling device was used for the settling test by measuring concentration of TSS, TP and TN for time and height. The pollutants removal rate was relatively high in the first 4 hours while 24 hours seem to be necessary to reach steady state in pollutant concentrations. However, there were no considerable differences in concentrations for height at a given time. This indicates most of particulate pollutant in the test seems to show independent settling with no interference to each other. Much part of particle sizes were distributed in the range of $10{\sim}100{\mu}m$. Average particulate fractions of TP and TN were estimated as 52.4% and 23.5%, respectively. This results explain why TN is difficult to remove by simple settling. This study indicates that a simple settling can provide effective method to remove significant amount of TSS and TP effectively and this can be used to protect urban river water quality.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.24 no.2
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• pp.226-235
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• 2019

Soluble silica profiles of the East Sea were described by comparing the 1970 Japanese data with the 1999-2000 ONR-JES data set, which is the most extensive collection of data currently available. Considering the ventilation mode change happened/ongoing and the features of the soluble silica to phosphate ratio we suggest a hypothesis that a utilization of soluble silica by the primary production might be exacerbated in the future. According to the silica limitation hypothesis composition of primary producers will be altered and followed by a weaker contribution of ballast against aggregates in the export production. Since the silicate cycle is deeply intertwined with the carbon cycle whether the warmed future ocean would behave like the East Sea appears to a potentially promising study theme.

• Journal of the Mineralogical Society of Korea
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• v.15 no.4
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• pp.293-304
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• 2002

Wet purification process for the selective separation of montmorillonite from Gampo 13 and 35 bentonite ores was studied using physical processes such as ultrasonic scrubbing, decantation and centrifugation. Ultrasonic Scrubbing of Gampo 13 and 35 bentonite ores was revealed excellent result at 7 wt.% of slurry density and was almost finished within 30 minutes in the sample of Gampo 13 and 10 minutes in the sample of Gampo 35, respectively After decantation, approximately 52 wt.% from the bentonite of Gampo 13 and 64wt.% from the bentonite of Gampo 35 were recovered as purified products and the CEC was reached up to 119.4 meq/100 g and 124.5 meq/100 g, respectively. Particle separation by centrifugation showed that most of the impurity minerals such as quartz and feldspar were removed within the condition of 1,000 rpm.

• Journal of the Korean Geotechnical Society
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• v.22 no.1
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• pp.53-61
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• 2006

Soil liquefaction occurs by complex dynamic interaction between soil particles and pore fluid. Therefore, experimental researches have been widely performed to analyze liquefaction phenomena. In this research, centrifuge tests were performed to analyze the liquefaction behavior of horizontal sand ground. Centrifugal acceleration was 40g and the thickness of model ground was 25cm, which simulates 10m thickness in prototype scale. Viscous fluid was used as pore fluid to remove the time scaling difference between dissipation and dynamic shaking. Test results showed that the dissipation of excess pore pressure is the combined behavior of solidification and consolidation. In addition, the solidification rate, the ground acceleration amplitude, and the dynamic permeability during solidification were influenced by the confining pressure.