• Title/Summary/Keyword: Ratio of permeability

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Effect of Nano-Bubble on Removal of Complex Heavy Metals (나노버블이 복합중금속(구리/납) 오염물 제거에 미치는 영향 분석)

  • Lee, Yang-Gyu;Han, Jung-Geun;Choi, Ju-Hyun;Kim, Dong-Chan;You, Seung-Kyong;Hong, Kikwon
    • Journal of the Korean Geosynthetics Society
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    • v.14 no.4
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    • pp.139-146
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    • 2015
  • This paper describes a effect of nano-bubble on removal of complex heavy metals, in order to remove pollutants of soil with copper (Cu) and lead (Pb) based on column test. It was conducted column test considering inflow and fine soil contents condition, and then it was analyzed removal effect of nano-bubble on Cu and Cu/Pb. The test result showed that the removal effect of the nano-bubble was higher than that of distilled water regardless of fine soil contents in case of Cu pollutant, and the removal effect of nano-bubble on heavy metals was found to have a significant impact on Pb than Cu in case of Cu/Pb pollutants. It was also analyzed that engineering properties (like a flow path and permeability) of soil due to void ratio has influenced a significant impact the pollutants removal of nano-bubble. The test results determined that nano-bubble can be applied as a flushing agent for priority target pollutant in complex heavy metals.

Physical Characterizations and In Vitro Skin Permeation of Elastic Liposomes for Transdermal Delivery of Polygonum aviculare L. Extract (마디풀 추출물의 경피 전달을 위한 탄성 리포좀의 물리적 특성 및 In Vitro 피부 투과 연구)

  • Han, Saet Byeol;Kwon, Soon Sik;Jeong, Yoo Min;Kong, Bong Ju;Yu, Eun Ryeong;Park, Soo Nam
    • Polymer(Korea)
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    • v.38 no.6
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    • pp.694-701
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    • 2014
  • In this study, Polygomun aviculare L. (P. aviculare L.) extract loaded elastic liposomes (ELPs) were investigated to enhance the transdermal delivery of P. aviculare L. extract composed of various flavonoids. ELPs were composed of egg phospholipids (PC) and edge activator ($Tego^{(R)}$ care 450) and the physical properties and in vitro permeation studies of ELPs were performed. Particle size ranged from 148.1 to 262.2 nm and deformability index was recorded as 11.5~25.4. Loading efficiency was from 53.1 to 66.3%. In vitro skin permeation studies using Franz diffusion cell demonstrated that ELP-4 having ratio of 85:15 for PC to $Tego^{(R)}$ care 450 exhibited the higher skin permeability than ELP-1, the general liposome without $Tego^{(R)}$ care 450. It was visually seen by fluorescence image restoration microscopy. The findings suggest that ELP-4 selected as the optimal formulation could be used as useful formulation for transdermal delivery of the extract.

Effects of Mixed Casting Solvents on Morphology and Characteristics of Sulfonated Poly(aryl ether sulfone) Membranes for DMFC Applications (직접 메탄올 연료전지용 술폰화 폴리아릴에테르술폰 전해질 막의 혼합 캐스팅 용매에 따른 형태 및 특성)

  • Hong, Young-Taik;Park, Ji-Young;Choi, Jun-Kyu;Choi, Kuk-Jong;Hwang, Taek-Sung;Kim, Hyung-Joong
    • Membrane Journal
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    • v.18 no.4
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    • pp.282-293
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    • 2008
  • Partially sulfonated poly(aryl ether sulfone) membranes were prepared from the sulfonated sulfone monomer, which was synthesized by a nucleophilic substitution, non-sulfonated monomers and potassium carbonate by a direct polymerization method and a subsequent solution casting technique with mixed solvents of N-methyl-2-pyrrolidone (NMP) and dimethylacetamide (DMAc). To investigate the effect of mixed solvent, the volume ratios of NMP and DMAc were varied in the range of $0{\sim}100%$ and the degrees of sulfonation of the copolymers were fixed as 50%. The surface properties of the resulting membranes were examined by scanning electron microscope (SEM) and atomic force microscope (AFM), and a comparative study of the morphology changes and the physicochemical properties such as proton conductivity and methanol permeability was achieved. It was found that proton conductivities depend on the volume ratio of NMP-DMAc mixed solvents, and the proton conductivity determined at the condition of $25^{\circ}C$ and 100% relative humidity was $1.38{\times}10^{-1}\;S/cm$ for the membrane prepared in the 50:50 v/v-% of NMP : DMAc mixed solvent.

The Paleovegetation at Dongdo of Is. Dokdo, Korea (한국 독도 동도의 고식생)

  • Yoon, Soon-Ock;Hwang, Sangill
    • Korean Journal of Plant Taxonomy
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    • v.38 no.4
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    • pp.583-599
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    • 2008
  • Dokdo, small island located in the eastern end of the Korean Peninsula, has been an uninhabited island for long time due to long distance from the land. Moreover, the steep slope of volcanic tuff at Dokdo is well drained for high permeability and Dokdo has few plain areas, swamps and very thin soil layers. In this study, pollen analysis at Dokdo was attempted on the profile of organic sandy soil for the first time in Korea owing to the marine climate environment with high humidity and precipitation including snowfalls in spite of unprofitable condition geologically or geomorphologically. While many historical, political researches have been accumulated for territorial problem of Dokdo with Japan, natural scientific researches with field work are not sufficient, and few paleoecological researches have been done. As a result of pollen analysis, the ratio of the NAP(Non-Arboreal Pollen) and spore was higher than AP(Arboreal Pollen), and the vegetation change existed by showing dramatic decrease of AP at the upper layer. AP was composed of almost Pinus, and a little Alnus, Quercus, Betula, Carpinus, Picea and Ulmus. NAP was composed of Gramineae, Compositae, Chenopodiaceae Cyperaceae, Caryophyllaceae, Liliaceae, Umbelliferae, Artemisia, Lobelia, Rumex, Polygonum. Increase of the NAP such as Gramineae, Artemisia and Chenopodiaceae, they would mostly have been transported from the other areas because agricultural activity is impossible at Dokdo. While one reason of Pinus thunbergii decrease could be regarded as environmental change, the other reason would be lumbering of pine trees by human activity which is adapted to Dokdo environment.

Transdermal Delivery of Quercetin Using Elastic Liposomes: Preparation, Characterization and In Vitro Skin Permeation Study (탄성 리포좀을 사용한 쿼세틴의 경피 전달: 제조, 특성 그리고 In Vitro 피부 투과 연구)

  • Park, Soo Nam;Lim, Myoung Sun;Park, Min A;Kwon, Soon Sik;Han, Seat Byeol
    • Polymer(Korea)
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    • v.36 no.6
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    • pp.705-711
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    • 2012
  • In this study, the elastic liposome consisted of egg phospholipids and edge activator ($Tego^{(R)}$ care 450) was prepared in order to supplement the defect of the conventional liposome. We prepared elastic liposome containing quercetin, known as natural antioxidant, and evaluated the vesicles size, elasticity, loading efficiency, stability, and in vitro skin permeation. The mean diameter of quercetin loaded elastic liposome formulations ranged between 208.2~303.4 nm and loading efficiency was observed 64.1~87.5%. The highest loading efficiency (87.5%) and deformability (28.3) were observed at the optimal ratio of 90 : 10 (egg phospholipids : $Tego^{(R)}$ care 450) among 0.1% quercetin loaded elastic liposome formulations. The elastic liposome formulation was selected for further transdermal permeation study. The elastic liposome ($129.9{\mu}g/cm^2$) exhibited more skin permeability than general liposome ($114.8{\mu}g/cm^2$) and 1,3-butylene glycol ($75.1{\mu}g/cm^2$) solution. This results suggest that the elastic liposome formulation using $Tego^{(R)}$ care 450 as a major edge activator could be useful for the delivery of active ingredient through the skin transdermal.

Study on CO2/N2 Mixture Gas Permeation Behavior through Polyethersulfone Membrane Treated by Plasma (플라즈마 처리된 폴리이써설폰 막의 CO2/N2 혼합가스의 투과거동에 대한 연구)

  • Park, Hee-Jin;Noh, Sang-Ho;Bae, Seong-Youl;Moon, Sei-Ki
    • Korean Chemical Engineering Research
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    • v.40 no.6
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    • pp.687-693
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    • 2002
  • The surface of polyethersulfone(PES) membrane treated by Ar, $NH_3$ plasma, and the effects were observed before and after the treatment. The membrane treated by Ar plasma was increased the O/C ratio and measured the hydrophilic group, and the one by $NH_3$ plasma was attached the amine group and the amino group. In addition, with the wettability of polyethersulfone membrane $CO_2$ and the polar functional groups of surface interacted increasingly. Thus by comparable increase of the soluble selectivity $CO_2$ to $N_2$ both the permeability and the selectivity of $CO_2$ was improved. The optimum condition for the $CO_2$ permeation and actual separation factor of the plasma treated membrane was as follows; the measurement of Ar-10 W-2 min plasma treatment was $13.19{\times}10^{-10}cm^3(STP)cm/cm^2{\cdot}s{\cdot}cmHg$ and 20.12, and the measurement of $NH_3$-50 W-2 min plasma treatment was $15.40{\times}10^{-10}cm^3(STP)cm/cm^2{\cdot}s{\cdot}cmHg$ and 20.06.

Functional Modification of Sanitary Nonwoven Fabrics by Chitosan Treatment (Part II) -Focused on Changes in Physical Properties- (키토산 처리에 의한 위생용 부직포의 기능성 개질화 (제2보) -물성 변화를 중심으로-)

  • Bae, Hyun-Sook;Kang, In-Sook;Park, Hye-Won;Ryou, Eun-Jeong;Kwon, Jay-Cheol
    • Journal of the Korean Society of Clothing and Textiles
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    • v.31 no.12
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    • pp.1662-1671
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    • 2007
  • The change in physical properties of polypropylene nonwoven fabrics used as top sheet for disposable sanitary goods was carried out using chitosan that is a type of natural polymer and has excellent human affinity by varying the molecular weight and concentration of chitosan. Low molecular weight(LMW) chitosan treated fabrics were found to be evenly coated on fabrics and had better dyeability by apparent dye uptake and its deodorization rate increased over the time. On the other hand, high molecular weight(HMW) chitosan treated fabrics showed higher add-on ratio and its dynamic water absorption rate and represented an increase in water transport rate. With chitosan treatment, its air permeability was improved. Regardless of the type of bacteria and chitosan concentration, its antibacterial activity was excellent in the case of the HMW chitosan treatment. In this regard, chitosan treatments by using a relatively high molecular weight was found as an effective way in the functional improvement of moisture properties and antibacterial activity including their most important performance in sanitary nonwoven fabrics.

A Study on the Removal of Ammonia by Using Peat Biofilter (미생물 활성토탄을 이용한 암모니아 제거에 관한 연구)

  • Choung, Youn Kyoo;Ahn, Jun Seong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.3
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    • pp.655-668
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    • 1994
  • Conventional deodorization filters using soil and compost reach the capacity limitation of deodorization in short period, because its removal mechanism primarily depends on adsorption. Therefore, in this study the experiment was performed on the removal of ammonia which is a strong inorganic malodor, frequently emitted from night soil treatment plants and sewage treatment plants, by seeding activated sludges on the bio-peat containing higher organic contents, water conservation capacity, permeability and lower pressure drop. As a result, in raw peat filter natural ammonia outlet was observed in consequence of pH increase resulted from ammonia ionizing in liquid phase. Ammonia removal mechanism primarily depended on the adsorption onto the anion colloidal substances in peat. In peat bio-filter, theoretical ammonium salts ratio was higher than that of raw peat, resulted from slight pH increase by microorganism activity, however, the experimetal value of ammonia-nitrogen accumulated in bio-peat was lower than that of raw peat because of nitrification by nitrifying bacteria. In the initial reaction period, adsorption was predominant in the ammonia removal mechanism, but nitrification was conspicuous after the middle period. Mass balance of nitrogen was established using experimental data of input $NH_3$ loading, output $NH_3$ loading, $NH_4{^+}$-N, $NO_x$-N, and Org-N. The critical time of unsteady state, which is the maximum activating point of microorganism in bio-filter, was determined using experimental data, and the ammonia adsorption curve was computed using regression analysis. On the basis of the results obtained by above analysis, the delay days for the saturation of adsoption capacity in peat bio-filter was calculated.

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Physical-chemical Properties and Phosphorus Adsorption Characteristics of Soils in Baicheng, China (중국 길림성 백성지역 흑개토의 이화학성 및 인산 흡착 특성)

  • Jin, Sheng-Ai;Lee, Sang-Mo;Choi, Woo-Jung;Yoo, Sun-Ho
    • Applied Biological Chemistry
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    • v.44 no.2
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    • pp.92-96
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    • 2001
  • Soil physical-chemical properties and phosphorous adsorption characteristics were investigated to obtain the informations of the appropriate fertilization and soil management in Baicheng region, China, where agricultural circumstances at present forces to consider the use of land for crop production. Soils were collected from one uncultivated and three cultivated lands on August 1993. Soil $_PH$ was very higher in uncultivated land than in cultivated land, their values were 10.2 and 7.4, respectively. Regardless of cultivation, soil organic matter contents were below 2%, and concentrations of available soil phosphorus expressed as Bray 1 P and Olson P were less than 10 mg P $kg^{-1}$, however, cation exchange capacity was higher than 20 cmol(+) $kg^{-1}$. For uncultivated soil, the values of exchangeable sodium percent and calcium saturation percent were higher than 100%. The major cation of soil saturation paste extracts was Na regardless of land use type. Based on electrical conductivity and sodium adsorption ratio of saturation paste extracts, uncultivated soil was classified as saline-sodic soil and cultivated soil was classified as sodic or normal soil. The maximum adsorption capacity of phosphorus calculated by Langmuir isotherm ranged from 406 to 521 mg P ,$kg^{-1}$. The constraints of soils in Baicheng regions for agricultural cops werw high salt concentration, unfavorable soil chemical composition such as low concentration of available phosphorous, and poor drainage due to soil dispersion by high Na concentration. Therefore, the soil in Baicheng region, need the application of phosphorus fertilizer to increase the soil fertility and the proper soil management to improve the soil physical property especially permeability and soil structure.

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Gas Separation Properties of Microporous Carbon Membranes Containing Mesopores (중간기공을 갖는 미세다공성 탄소 분리막의 기체 투과 특성)

  • Shin, Jae Eun;Park, Ho Bum
    • Membrane Journal
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    • v.28 no.4
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    • pp.221-232
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    • 2018
  • The silica containing carbon ($C-SiO_2$) membranes were fabricated using poly(imide siloxane)(Si-PI) and polyvinylpyrrolidone (PVP) blended polymer. The characteristics of porous carbon structures prepared by the pyrolysis of polymer blends were related with the micro-phase separation behaviors of the two polymers. The glass transition temperatures ($T_g$) of the mixed polymer blends of Si-PI and PVP were observed with a single $T_g$ using differential scanning calorimetry. Furthermore, the nitrogen adsorption isotherms of the $C-SiO_2$ membranes were investigated to define the characteristics of porous carbon structures. The $C-SiO_2$ membranes derived from Si-PI/PVP showed the type IV isotherm and possessed the hysteresis loop, which was associated with the mesoporous carbon structures. For the molecular sieving probe, the $C-SiO_2$ membranes were prepared with the ratio of Si-PI/PVP and the pyrolysis conditions, such as the pyrolysis temperature and the isothermal times. Consequently, the $C-SiO_2$ membranes prepared by the pyrolysis of Si-PI/PVP at $550^{\circ}C$ with the isothermal time of 120 min showed the $O_2$ permeability of 820 Barrer ($1{\times}10^{-10}cm^3(STP)cm/cm^2{\cdot}s{\cdot}cmHg$) and $O_2/N_2$ selectivity of 14.