• Title/Summary/Keyword: Membrane leakage

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An Experimental Study on the Damage of Waterproofing Membrane due to Oil ingredient of Underground Structures (유류성분이 지하구조물의 방수층 손상에 미치는 영향에 관한 실험적 연구)

  • Song Je-Young;Kang Hyo-Jin;Kwak Kyu-Sung;Oh Sang-Keun
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2006.05a
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    • pp.177-180
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    • 2006
  • The accidents of oil leakage is increasing in the Underground Concrete structures for Oil Storege. In the result, the waterproofing in the underground structures is melt down and cannot fulfil its Performance. This study shows an experimental study in the effects of the oil leakage to on the performance of Waterproofing Materials. In order to investigate the actual condition and the problems, a comparative analyses were conducted considering the various types of leakage. Utilizing the obtained results at the basic data for test methods and the standard of quality, we intended to propose a strategy to develop an innovated waterproofing Materials and improve the clean environment of underground structures.

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On the New Design of Liquid Dome Chair in Membrane Type LNG Carrier (멤브레인형 LNG선박의 리퀴드 돔 체어 구조개발)

  • Kim, Jeong-Hwan;Kim, Yooil
    • Journal of the Society of Naval Architects of Korea
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    • v.54 no.5
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    • pp.361-367
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    • 2017
  • A membrane type LNG cargo tank is equipped with a pump tower and a liquid dome for loading and unloading of LNG. However, the membrane running continuously on the tank wall to prevent leakage of LNG is interrupted by the liquid dome, hence care should be taken in the design of liquid dome and its substructures. In case of GTT NO96 membrane type cargo containment system, chair structure is arranged along the periphery of the liquid dome targeting to support the membrane which is exposed to the both hull girder and thermal load. This paper proposes a new and simple chair structure, which outperforms traditional design from productivity point of view maintaining same level of structural safety. Strength assessment on the new design was performed to guarantee the structural safety of the new design, which includes strength, fatigue and crack propagation analysis.

Effect of Protective Compounds on the Survival, Electrolyte Leakage, and Lipid Degradation of Freeze-Dried Weissella paramesenteroides LC11 During Storage

  • Yao, Amenan A.;Wathelet, Bernard;Thonart, Philippe
    • Journal of Microbiology and Biotechnology
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    • v.19 no.8
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    • pp.810-817
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    • 2009
  • The effect of cryoprotectants (maltodextrin+glycerol) and cryoprotectants+antioxidant [ascorbic acid and/or butylated hydroxytoluene (BHT)] mixtures on the survival, electrolyte leakage, and lipid degradation of freeze-dried Weissella paramesenteroides LC11 during storage was investigated and compared with that of the control (cells without additives) over a 90-day storage period at 4 or $20^{\circ}C$ in glass tubes with water activity ($a_w$) of 0.23. The survival, electrolyte leakage, and lipid degradation were evaluated through colony counts, electrical conductivity, and thiobarbituric acid reactive substances (TBARS) content, respectively. The fatty acids composition was determined by gas chromatography, in both the total lipid extract and the polar lipid fraction, and compared with that of the control after the 90-day storage period. As the storage proceeded, increases in leakage value and TBARS content, as well as a decrease in viability, were observed. After 90 days of storage, the major fatty acids found in both the total lipid extract and the polar lipid fraction were palmitic (16:0), palmitoleic (16:1), stearic (18:0), oleic (18:1), linoleic (18:2), and linolenic (18:3) acids. The survival, leakage value, TBARS content and 18:2/16:0 or 18:3/16:0 ratio were the greatest for the protected strain held at $4^{\circ}C$. Cells with the cryoprotectants+BHT mixture showed the highest percentage of survival and 18:2/16:0 or 18:3/16:0 ratio in both lipid extracts, as well as the lowest leakage value and TBARS content after the 90-day storage period. Drying cells with the cryoprotectants+BHT mixture considerably slowed down polar lipid degradation and loss of membrane integrity, resulting in improved viability during storage.

Evaluation of Two Biologically Active Compounds for Control of Wheat Root Rot and its Causal Pathogens

  • Hashem, Mohamed;Hamada, Afaf M.
    • Mycobiology
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    • v.30 no.4
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    • pp.233-239
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    • 2002
  • The main aim of this study is to evaluate the efficiency of two biologically active compounds(Strom and F-760) in control of wheat root rot disease and its causal organisms. Fusarium graminearum, F. oxysporum, F. solani and Bipolaris sorokiniana were used as target organisms. In vitro, the two compounds showed fungicidal effect on all investigated pathogens resulted in suppression of radial growth and mycelial dry weight of them. Under greenhouse conditions, treatment of wheat grains with either Strom or F-760 before cultivation significantly reduced the percent of disease distribution as well as the mean disease rating of plants in both seedling and flowering stages. Fresh and dry weights of plants as well as water maintenance capacity were increased as the result of applying these compounds as seed dressing. Also data showed that the membrane stability of plants was injured as a result of infection with all investigated organisms, while this injury was alleviated when F-760 and Strom were applied. The $K^+$ efflux and the leakage of UV absorbing metabolites was stimulated with fungal infection. However, F-760 and Storm treatment partially retarded the stimulatory effect on leakage of $K^+$ and UV-absorbing metabolites of fungal infected plants. On the other side, the fungal infection had inhibitory effects on pigment fractions(chlorophyll a, b, and carotenoids) biosynthesis in wheat leaves. This retarding effect was partially or completely alleviated as the grains were treated with the applied compounds.

A Study on the Separation of Electrolyte from Amino Acid Solution through Electrodialysis (전기투석법을 이용한 아미노산으로부터 전해질 분리정제에 관한 연구)

  • 김석곤;한정우;김한성;전경용;조영일
    • Membrane Journal
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    • v.4 no.3
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    • pp.163-170
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    • 1994
  • The separation of inorganic salt from amino acid solution using was performed electrodialysis. In order to review the availability of electrodialysis using isoelectric point of amino acid as a bio-separation technique, electrodialysis stacks were designed using ion exchange membrane. Separation of NaCl from amino acid solution was performed in the condition similar to amino acid fermentation process. To obtain otimum conditions of separation, leakage of amino acid depending of pH and limiting current density were measured. On the basis of optimum condition, removal of NaCl and leakage of amino acid were investigated quantitatively in batch and continuous process, and current efficiencies were also obtained. As a result of batch experiment for 11 hours each amino acid solution, removal efficiencies of NaCl were in the ranges of 96.1~96.2%. Amino acid leakage rate of glycine, methionine, alanine were 2.5, 1.7, 2.0% respectively. Current efficiencies were in the ranges of 44.5~44.6%. As a result of continuous experiment in various flow rate of each amino acid solution, it took 120 ~ 150 min to reach to steady state. Removal efficiency of NaCl was increased as the flow rate was decreased, but current efficiency was decreased. At the steady states, there were no leakage of amino acid.

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Physiological Responses of Tobacco(Nicotiana tabacum L.) Leaves of Different Age to Oxyfluorfen (Oxyfluorfen에 대한 담배의 엽령별 생리적 반응)

  • Lee, H.J.;Shin, C.S.;Han, S.U.;Guh, J.O.
    • Korean Journal of Weed Science
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    • v.18 no.1
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    • pp.69-75
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    • 1998
  • Responses of tobacco(Nicotiana tabacum cv. Xanthi) leaves of different age to diphenyl ether herbicide oxyfluorfen were evaluated with respect to cellular leakage, chlorophyll loss, and membrane lipid peroxidation. When tobacco leaves of different age were incubated under light condition at $25^{\circ}C$ following 12hr dark incubation. Significant electrolyte leakage from the treated tissues into the bathing medium occurred. The change of electrolyte leakage was proportional to the oxytluorfen concentration and the duration of light exposure to the tissues. Electrolyte leakage from the tissues treated with oxyfluorfen was highly dependent on the leaf age. From the tissues of younger age, more electrolyte leakage occurred and lag period was greatly reduced. Chlorophyll loss and membrane lipid peroxidation, as measured by malondialdehyde production, caused by oxyfluorfen treatment were also dependent an the age of treated leaf tissues. In conclusion, physiological responses of tobacco leaves to oxyfluorfen greatly varied with the age of treated tissues, and thus tobacco plants could be used as appropriate materials for studying the mechanisms of tolerance to diphenyl ether herbicides.

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Development of Coencapsulating Technology for the Production of Chitosanoligosaccharides

  • Lee, Ki-Sun;Chio, Myeong-Rak;Lim, Hyun-Soo
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.5 no.5
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    • pp.345-349
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    • 2000
  • To easily separate chitosanoligosaccharides by size exclusion, an coencapsulating technology of substrate and enzyme was developed. The membrane was composed of alginate and a divalent cation such as calcium. Chitosan and chitosanase were enveloped in this membrane and the product released to medium by size exclusion. The capsule was stabilized in a 2% acetic acid solution (pH 5.0) containing 0.145 M CaCO$_3$. The leakage of substrate caused by the agitation speed was controlled by increasing alginate and CaCO$_3$concentrations. The lower limit of the alginate concentration and the agitation speed were 0.5% and 49rpm, respectively. Membrane thickness and capsule diameter were 10$\mu\textrm{m}$ and 2.5mm, respectively. By TLC analysis, the composition of chitosanoligosaccharides were mainly 3-6 mers. The molecular weight distribution of the released oligosaccharides ranged from 262 to 3624 Da by GPC.

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INTERACTION OF TENECIN FRAGMENTS WITH LIPOSOMES

  • Park, Myeong-Jun;Cho, Hyun-Sook;Hong, Sung-Yu;Yoon, Jeong-Hyeok;Lee, Keun-Hyeong;Moon, Hong-Mo;Cheong, Hong-Seok
    • Proceedings of the Korean Biophysical Society Conference
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    • 1996.07a
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    • pp.37-37
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    • 1996
  • Tenecin fragments are antimicrobial and antifungal peptide from Tenebrio molitor with highly positive charged amino acid residues. To elucidate their membrane selectivity and molecular mechanism, various forms of tenecin fragments were synthesized, and their interaction with acidic phospholipid, Gram (+), fungal and human erythrocyte membrane were investigated by ANTS/DPX leakage, membrane binding and fusion assay. (omitted)

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A Study on the field application analysis for high adhesive spray type of degenerated and rubberized asphalt membrane material (스프레이식 고점착 변성 고무 아스팔트 도막 방수재의 재료 및 공법에 관한 실험적 연구)

  • Oh, Sang-Keun;Song, Je-Young;Kim, Jin-Seong;Lee, Nam-Kyoo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2006.11a
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    • pp.61-65
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    • 2006
  • Urethane, epoxy, acrylic have common property to adhere on the concrete dried surface in the waterproofing materials at present. In the wet condition, however, the materials such as urethane, epoxy, acrylic need a long hardening time and it become a reason of water leakage as the materials breaking down. it is one of the problem to adhere to the substrate. Therefore, in this thesis, I focused to assure the structural safety and durability and quality for waterproofing and safe of construction cost by cut down the cost of labor and reduce the term of works as searching the application of field condition for hish adhesive spray type of degenerated and rubberized asphalt membrane material.

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The Measurement of Membrane Deformation Behavior in Kogas Pilot LNG Storage Tank by the use of Mechanical/Electrical Sensor (I) (기계적/전기적 측정 센서를 이용한 Kogas Pilot LNG 저장탱크 멤브레인 변형 거동 측정(I))

  • Kim Y.K.;Hong S.H,;Oh B.T.;Yoon I.S.;Kim J.H.;Kim S.S.
    • Journal of the Korean Institute of Gas
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    • v.7 no.3 s.20
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    • pp.13-17
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    • 2003
  • A membrane unit for Liquefied Natural Gas (LNG) storage tank is a structural member which is designed specifically for preventing undesirable LNG leakage. Membrane units have to endure gas and liquid pressures by LNG and thermal stresses by the contact with cryogenic liquid of $-162^{\circ}C$. It is of importance to assure the strengths of membrane by experimental stress analysis under the temperature of LNG. In this paper, we proposed measurement system using commercial electrical strain gage and mechanical extension meter designed for this study.

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