• Title/Summary/Keyword: filteration

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Dose Characteristics by the Co-60 Source Oscillations in High Dose Rate After Loading Irradiations (고선량율 원격강내조사의 코발트-60 이동선원에 의한 선량특성)

  • 최태진;김옥배;노홍균
    • Progress in Medical Physics
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    • v.1 no.1
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    • pp.51-60
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    • 1990
  • Dose distributions around Co- 60 moving source in high dose rate remote afterloading unit, Buchler 3K unit, were experimented with X-omat V films and calculations. In our experiments, film dosimetries have achieved to evaluated the axial dose distributions for source oscillations were 0, 3.5, 5.0 and 6.0 cm in periodically, In results, the dose distributions in axial of source movement showed apparently higher than in transverse direction caused by source locations, dwelling time and air gap in the applicator. In the calculations, the dose rate was derived by using the inverse square law, filteration corrections and Meisberger constant for scatter corrections as source movings. In our experiments and calculations, the average dose uncertainties were showed -2.1$\pm$1.9% in fixed sourdce, -2.9$\pm$1.8%, -7.4$\pm$6.1% and -6.7$\pm$4.6% at 3.5 cm, 5.0 cm and 6.0 cm source oscillations, but the calculations have showed very close to experimental dose rate within 4 cm distance from source.

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A Study on The Filtration Characteristics of Magnetic Fibrous Polymeric Filter with Packing Density Profile as a New Oil Filter (윤활시스템용 오일필터로서 충전밀도 변화에 따른 자성폴리머 필터의 여과특성 연구)

  • 최기영;안병길;최웅수;권숙인;권오관
    • Tribology and Lubricants
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    • v.11 no.2
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    • pp.8-14
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    • 1995
  • The filtration of the magnetic fibrous polymeric filter with packing density profile made of a self-bonded, nonwoven structure comprising a thermoplastic polymer and a magnetic substance was investigated using an oil filter tester, a particle quantifier and an image analyzer system. The magnetic fibrous polymeric filter showed excellent filtration efficiency compared with conventional paper filter. From the experimental results, It is deduced that the filtration mechanism of conventional paper filter is only the function of physical porosity by surface filteration. On the other hand, the newly magnetic fibrous polymeric filter is designed with a new concept in filtration mechanism. That is, it has a dual function of depth and magnetic filters by physical porosity and magnetic attraction. The newly magnetic fibrous polymeric filter has been shown to be a highly effective oil filter for lubrication systems.

Identification and Purification of Juvenile Hormone Binding Protein from nyphantria cunea Drurv (미국흰불나방(Hyphuntrio cuneo D.)의 유충호르몬 결합단백질의 확인 및 정제)

  • 이인희;김학열
    • The Korean Journal of Zoology
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    • v.36 no.2
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    • pp.238-244
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    • 1993
  • We identified juvenile hormone binding protein (JHBP) from last instar larval hemollvnph of Hvphantria cunea using gel filtration and non-SDS PAGE. Two kinds of JHBP in hemollnnph were found at two peaks by gel filtration (Sephadex G-100) and also at Rm values of 0.13 and 0.57 by non-SDS PAGE. JHBP was partially purified using anion exchange chromatosraphv, preparative gel filteration, and preparative PAGE. Dextrin coated charcoal (DCC) binding assay was employed to monitor the location of JHBP in chromatographic profile during the purification process. Purity of JHBP was checked by silver staining of 1091 SDS-Polyacrvlamide.

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Chemical Characteristics of Cell-Wall Polysaccharides in Differentiating Xylem of Populus deltoides M. (미류나무 분화조직중 세포벽다당류의 화학적 성상)

  • Eom, Tae-Jin;Park, Yun-Je
    • Journal of the Korean Wood Science and Technology
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    • v.26 no.3
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    • pp.26-32
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    • 1998
  • The chemical composition of differentiating xylem of Populus deltoides M. were investigated and compared with those from sapwood. The cell wall polysaccharides were extracted sequentially from a differentiating xylem and sugar composition was analyzed with G.L.C, H.P.L.C and gel chromatograpy. The pectin substance and hemicellulose are rich in the cell wall of differentiating xylem. The $H_2O$ extract polysaccharides from differentiating xylem were composed with xylose-glucose residues which seem to be xyloglucan and a pectin. The arabinogalactan and the mannan were extracted with $Na_2CO_3$ solution and also the xylan was extracted with KOH solution. Sugar composition of each fractions in gel filteration of purified $H_2O$ polysaccharide suggests that the xyloglucan can be extracted with $H_2O$ from differentiating xylem.

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Chromatographically Purified Porphyran from Porphyra yezoensis Effectively Inhibits Proliferation of Human Cancer Cells

  • Kwon, Mi-Jin;Nam, Taek-Jeong
    • Food Science and Biotechnology
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    • v.16 no.6
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    • pp.873-878
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    • 2007
  • In this study, we isolated porphyran was isolated from the red seaweed Porphyra yezoensis and assessed in terms of in vitro anti-proliferative activity. Sequential anion-exchange and gel-filtration chromatography led to purification of 3 porphyrans of different molecular masses, which contained <$50\;{\mu}g/mL$ protein and >$10\;{\mu}g/mL$ porphyran. Crude porphyran inhibited cell growth in a dose-dependent manner (0-5 mg/mL). When HT-29 colon cancer cells and AGS gastric cancer cells were cultured with various concentrations of the purified porphyran, cancer cell growth was inhibited by 50% at a low concentration (5 or $10\;{\mu}g/mL$). Furthermore, the polysaccharide portion of the porphyran preparation, rather than the protein portion, is the most effective at inhibiting cancer cell proliferation via apoptosis, as indicated by increased caspase-3 activity. Our results indicate that purified porphyran has significant in vitro anti-proliferative activity (p<0.05).

Natural Antibiotic Activity of Lactobacillus helveticus (Lactobacillus helveticus의 자연항생작용에 관한 연구)

  • Choi, Sang-Hun;Kim, Dong-Sin
    • Journal of Dairy Science and Biotechnology
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    • v.17 no.1
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    • pp.11-15
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    • 1999
  • The objective of this study was to extract and purity the antibacterial agent from the fermented milk with Lactobacillus helveticus CH-1. The extraction and purification of antibacterial agent from the Lb. helveticus fermented milk were carried out by methanol extraction, acetone extraction, Sephadex G-200 gel filteration and thin layer chromatography and the results were as followings. The antibacterial activity of methanol-acetone extraction showed antibacterial activity against test organisms, B. subtilis, E. coli, Pseu. fluorescens, Sal. typhimurium, Shi. flexneri, and Sta. aureus. Sephadex G-200 gel chromatography showed only antibacterial activity from 33 to 37th fractions of 60 fractions. The agent purified from TLC plate confirmed the antibacterial activity by the means of bioautography.

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Preparation of Oil dispersants using polyoxyethylene Monooleate and Oleyether and its Effect on dispersing efficiency to Bunker B Oil (Polyoxyethylene monooleate 및 oleyther계 유분산제의 제조와 Bunker B유의 분산효율에 미치는 영향)

  • Yeom, Guy-Seol;Kang, Doo-Whan
    • Journal of the Korean Applied Science and Technology
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    • v.12 no.1
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    • pp.59-67
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    • 1995
  • Oil dispersants using polyoxyethylene monooleate, polyoxyethylene oleylether, and poly(oxypropylene-oxyethylene)glycol block copolymer were prepared, and oil dispersant efficiency was measured using vertical shaking flask method to 4 kinds of Bunker B oil with different physical properties by appling the prepared dispersants. Although the dispersant efficiency was differed according to the differences of physical properties of Bunker B oil, the dispersant prepared using polyoxyethylene oleylether was the most effective to disperse the oil into water. The impurities like surfur contained in sample oil have to be removed by filteration to obtain the correct degree of absorption using UV spectrophotometer.

The effect of natural condiments on peptic activity (Pepsin의 단백소화작용(蛋白消化作用)에 미치는 조미료(調味料)의 영향(影響))

  • Rho, Sook-Nyung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.4 no.1
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    • pp.49-53
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    • 1975
  • The effect of natural condiments on peptic hydrolysis of casein in vitro has been studied, peptic activity was determined by the colorimetric method using folin reagent. The obstructive compounds on colorimetry from hydrolyzates of casein were separated by gel filteration method using sephadex G-10 column and 0.05M NaCl. Zinger and red pepper $(0.1{\sim}1.0%)$ were found to have slightly supressing effect for protein digestive action of pepsin. But garlic, green onion and onion acted as synergist for protein digertive action of pepsin.

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Purification and Seperation of Chitooligosaccharides Hydrolyzed by Chitosanolytic Enzyme (Chitosanase의 분해에 의한 Chitooligo당의 분리 정제)

  • Ryu, Byeong-Ho;Bin, Jae-Hun;Lee, Seong-Ho
    • The Korean Journal of Food And Nutrition
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    • v.8 no.1
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    • pp.43-49
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    • 1995
  • This studies were carried out to purification and seperation of chitooligosaccharides which containing excellent biological active substance. After deacetylation of chitosan (DAC%), DAC-45%, DAC-70%, DAC-95% and DAC-99% were used substrates and hydrolyzed by chitosanase (Bacillus pumilus BN-262) DAC-99% has excellent hydrolyzate which contained several chitooligosaccharides. Therefore, chitosan was hydrolyzed DAC-90 as substrate by chitosanase, and then purified and seperated of chitooligosaccharides Gel filteration and HPLC. This oligosaccharides composed with GlcN0, GlcN2, GlcN3, Glc5 and GlcN6.

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A Practice-Oriented Study on Sawdust File Filteration Composting of High Moisture Pig Slurry (고수분 돈분슬러리의 톱밥여과 퇴비화 현장적용 연구)

  • Ryoo, J.W.
    • Journal of Animal Environmental Science
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    • v.14 no.2
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    • pp.129-138
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    • 2008
  • This study was carried out to investigate the operating characteristics, water balance and chemical properties of compost during the composting with pig slurry on-farm trial. The composting plant with sawdust pile filteration was done in a forced aeration inside a house and equipped with a turning machine moving on a rails. The composting pit was 4.6m wide, 53m long and the maximum height was 2m. A field scale aerobic composting facility was tested the composting efficiency of high moisture pig slurry. The sawdust materials remained 6 months. Pig slurry was added to compost pile every other day during 6 months run. The temperature in compost pile and compost house, and input and output of moisture were measured during composting process. The result are summarized as follows; 1. The temperature of compost was varied in range of at $22.4^{\circ}C{\sim}71.1^{\circ}C$. After turning, the composting temperature decreased to $50^{\circ}C{\sim}36^{\circ}C$ during $3{\sim}5$ hours, and then raised to $64.5^{\circ}C$ 2. The temperature of compost house was maintained $20^{\circ}C{\sim}30^{\circ}C$, and relative humidity was varied in range of $50{\sim}99%$. 3. BOD, CODcr and SS of leachate water was reduced 89.5%, 81.2%, 97.5%, respectively. 4. The content of heavy metal in the final compost was lower those of Korea standards. 5. The amount of effluent was 10.2%. Total evaporation during composting Period were 74.8%. The amount of slurry per $1m^3$ sawdust was $3.16m^3$ without treatment of effluent output.

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