• 한국환경농학회지
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• 제21권2호
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• pp.130-135
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• 2002

토양 중에서 농약을 대공극과 숨골을 통하여 지하수로 이동시킬 수 있는 매체로 작용하는 물분산성 콜로이드 함량과 그 안정성은 여러 가지 토양의 이화학적 특성에 의해 결정된다. 본 연구에서는 제주도 감귤원에서 채취한 30개 토양을 사용하여 pH, 유기물, oxalate 용액 추출성 Al과 Fe 등이 물분산성 콜로이드의 함량에 미치는 영향을 조사하였다. 토양의 pH가 증가할수록 물분산성 콜로이드의 함량이 높았으며, pH 5$\sim$6 이상의 토양에서는 표면 음전하의 증가에 따라 콜로이드의 안정성이 높아질 가능성이 많은 것으로 나타났다. 낮은 pH 조건에서는 표면 음전하의 감소와 함께 활성 Al 또는 Fe 함량이 증가함에 따라 콜로이드의 응집 현상이 촉진되는 것으로 나타났다. 물분산성 콜로이드의 함량은 콜로이드의 입단화를 촉진시킬 수 있는 토양의 유기물 함량과 반비례하였으며, 유기탄소 함량 5% 이하의 토양에서 특히 물분산성 콜로이드의 함량이 많게 나타날 가능성이 높은 것으로 나타났다. Oxalate 용액 추출성 Al과 Fe 함량 또한 분산성 콜로이드의 함량과 반비례하였으며, Al과 Fe의 산화물 또는 수산화물들 그리고 치의 유기물 복합체는 토양 중에서 콜로이드 형태로 존재할 수도 있으나 점토광물의 입단화를 촉진시키는 결합제로 작용함으로써 물분산성 콜로이드의 분산을 억제하는 것으로 판단되었다.

• 한국산업융합학회 논문집
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• 제9권4호
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• pp.323-330
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• 2006

As the interest in environmental pollution resulting from recent industrial development is converging, wastewater treatment problem of dying processing is one of important pending issue. Usually, flow mediation earth and settling pond etc. of processing plant to handle water or wastewater. Mediation is the wastewater that flowed past settling pond than material of heavy particles, water weight colloid particles that big solids are removed but are suspensibility material settlement exclusion impossible. So, we need flocculation and coagulation action to remove materials from this colloid state. For flocculation and coagulation action chemical agents to add back, addition of chemical agents forms floc of could settle size. That is, shorten the sedimentation time and quality of processing water because promoting sedimentation doing to do fines or suspended solids and colloid can materials large size and also, flocculation to annex efficiency of filtration augment. Therefore, I executed this research to prove that improving organic matter and chromaticity of treated water of processing epochally using organic coagulant informed positive ion co-polymerization superior in color wastewater through this research.

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1449-1454
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• 2014

The co-sensitization of N719 with a cyclic thiourea functionalized organic dye, coded AZ5, for dye-sensitized solar cells (DSSCs) was demonstrated. Due to its intensive absorption in ultraviolet region, AZ5 could compensate the loss of light harvest induced by triiodide, thereby the short-circuit photocurrent density ($J_{sc}$) was increased for co-sensitized (N719+AZ5) DSSC. Moreover, the electron recombination and dye aggregation were retarded upon N719 cocktail co-sensitized with AZ5, thus the open-circuit voltage ($V_{oc}$) of co-sensitized device was enhanced as well. The increased $J_{sc}$ (17.9 $mA{\cdot}cm^{-2}$) combined with the enhanced $V_{oc}$ (698 mV) ultimately resulted in an improved power conversion efficiency (PCE) of 7.91% for co-sensitized DSSC, which was raised by 8.6% in comparison with that of N719 (PCE = 7.28%) sensitized alone. In addition, co-sensitized DSSC exhibited a better stability than that of N719 sensitized device probably due to the depression of dye desorption.

• 방사성폐기물학회지
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• 제20권3호
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• pp.279-296
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• 2022

The fundamental characteristics of groundwater colloids, such as composition, concentration, size, and stability, were analyzed using granitic groundwater samples taken from the KAERI Underground Research Tunnel (KURT) site by such analytical methods as inductively coupled plasma-mass spectrometry, field emission-transmission electron microscopy, a liquid chromatography-organic carbon detector, and dynamic light scattering technique. The results show that the KURT groundwater colloids are mainly composed of clay minerals, calcite, metal (Fe) oxide, and organic matter. The size and concentration of the groundwater colloids were 10-250 nm and 33-64 ㎍·L^-1, respectively. These values are similar to those from other studies performed in granitic groundwater. The groundwater colloids were found to be moderately stable under the groundwater conditions of the KURT site. Consequently, the groundwater colloids in the fractured granite system of the KURT site can form stable radiocolloids and increase the mobility of radionuclides if they associate with radionuclides released from a radioactive waste repository. The results provide basic data for evaluating the effects of groundwater colloids on radionuclide migration in fractured granite rock, which is necessary for the safety assessment of a high-level radioactive waste repository.

• 한국염색가공학회지
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• 제20권4호
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• pp.31-42
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• 2008

Tricrecyl phosphate(TCP)-containing polyurea microcapsules were prepared by interfacial polymerization using aromatic 2,4-toluene diisocyanate(TDI) and ethylenediamine(EDA) as wall forming materials. The effects of the protective colloids of polyvinylalcohol(PVA) and gelatin were investigated through experimentation. The mean size of prepared polyurea microcapsules was smaller and the surface morphology of the microcapsule prepared by the PVA as protective colloid was much smoother than the gelatin. As the concentration of protective colloid increased, the wall membrane of the polyurea microcapsules became more stable, the thermal stability of the wall membrane increased, the mean particle size became smaller, and the particle distribution was more uniform. PET containg microTCPs have a higher activation energy of decomposition, higher char content and lower heat of combustion.

• 대한핵의학회지
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• 제37권5호
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• pp.301-307
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• 2003

목적: 리피오돌은 간암환자의 간동맥으로 투여시 암에 많이 섭취된다. 이 연구에서는 Re-188-황 교질/리피오돌을 제조하여 생체내분포를 보았다. 재료 및 방법: Re-188-황 교질/리피오돌을 마우스의 꼬리정맥으로 주사한후 1 시간 후에 생체내 분포를 확인하였다. 간암을 유발시킨 백서의 좌심실로 Re-188-황 교질/리피오돌을 주사하고 5 분후의 생체내 분포와 간의 자가방사사진을 보았다. 결과: Re-188-황 교질/리피오돌을 마우스의 꼬리정맥으로 주사한 후 1시간(n=3)섭취율(% ID/organ)은 간에서 $5.2{\pm}0.7$, 폐는 $91.0{\pm}1.7$이었다. 간암을 유발시킨 백서의 좌심실로 Re-188-황 교질/리피오돌을 주사한 후 5 분(n=4)의 정상간의 섭취율(% ID/g)은 $0.41{\pm}0.28$, 간암은 $1.88{\pm}1.57$, 폐는 $1.65{\pm}1.54$였으며, 자가방사사진에서도 간암부위의 섭취가 정상적인 간조직 보다 증가되었다. 결론: Re-188-황 교질/리피오돌을 동맥으로 투여시 간암부위의 섭취가 정상적인 간조직보다 많아 간암치료용 방사성의약품으로서 사용할 수 있음을 알았다.

• 한국토양비료학회지
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• 제6권1호
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• pp.67-73
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• 1973

Soil humic substances are defined as a humified part of the soil organic matters and regarded to play beneficial roles for colloid chemical properties and the fertility of the soils. This paper is referred to review the present trend of the studies on the forming processes of humic substances and on the effect on plant metabolism by some organic compounds that are directly absorbed by plants. It is generally considered that the humic substances are formed organic matters in soil or plant materials through numerous organic or biochemical processes. However, the nature of the constituting "core" and of attachment of carbohydrate, nitrogen containing compounds like protein, phenolic compounds and metals to the core are unclear though various models are suggested. It is reviewed that some organic compounds, phenclic acids, derived from humic substances are effective on plant metablism in many cases, although the mechanisms are remained to be clarified.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.1398-1402
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• 2005

Riverbank filtration is a natural process using alluvial aquifers to remove contaminants and pathogens in river water for the production of drinking water. In riverbank filtration, the understanding of contaminant transport is an important task for the production of high quality drinking water. This study investigates the transport behavior of hydrophobic organic contaminants when colloids (dissolved organic matter and bacteria) are present in the aquifer. A mathematical model for the transport of contaminants is developed and solved numerically for various situations. Results show that in the riverbank filtration the presence of DOM and bacteria enhances the mobility of contaminant significantly. Sensitivity analysis indicates that the distribution of the total aqueous Phase contaminant is significantly affected by distribution coefficients which account for affinity of solid or colloidal Phase to contaminant.

• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2575-2580
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• 2010

We present a method for chemically reducing silver alkylcarbamate complex with hydrazine to synthesize silver nanocolloids in an organic solvent using polyvinylpyrrolidone (PVP) as the stabilizer. To determine the optimal conditions for preparing stable silver colloids of controlled size and shape, the silver 2-ethylhexylcarbamate (Ag-EHCB) complex, PVP, hydrazine, and 2-propanol solvent concentrations in the reaction mixture were varied. The initial colloid has a mean particle diameter of 5-80 nm, and it exhibits an absorption band with various shapes in the UV region with a maximum near 420 nm. UV-vis spectroscopy, TEM, and X-ray diffraction techniques were used to investigate the formation and growth process of the metallic silver nanocolloids.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.209-219
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• 2018

Colloidally stable organic-inorganic (O-I) hybrid nanoparticles could be prepared using an alkoxysilanefunctionalized amphiphilic polymer (AFAP) precursor. O-I hybrid sols could maintain colloidal stability for six months even at 45% solid content and be coated onto glass as well as PET film to form transparent O-I hybrid films. The formation of O-I hybrid nanoparticles dispersed in cured coating films could be confirmed using scanning electron microscopy. The cured coating film showed 3H and 5H pencil hardness on PET and glass, respectively. Nanoindentation measurements also showed that their modulus and hardness was varied with the type of AFAP used in its preparation.