• Title/Summary/Keyword: Chloride permeability

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Performance and characterization of PEG400 modified PVC ultrafiltration membrane

  • Aryanti, P.T.P.;Yustiana, R.;Purnama, R.E.D.;Wenten, I.G.
    • Membrane and Water Treatment
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    • v.6 no.5
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    • pp.379-392
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    • 2015
  • Polyvinyl chloride (PVC) ultrafiltration membrane was prepared by blending 12 wt.% of PVC in N, N-dimethylacetimide (DMAc) with polyethylene glycol 400 (PEG400) as an additive. The influence of PEG400 concentration on the PVC membrane morphology, permeability, fouling and rejection were investigated. Fouling and rejection of the PVC membrane were characterized by dextran T-100 filtration. The results showed that membrane water flux was increased up to $682Lm^{-2}h^{-1}$ when 28 wt.% of PEG400 was added into the PVC membrane solution. The best membrane performance with a low fouling and a high selectivity was achieved by adding 12 wt.% concentration of PEG400, which resulted in 90% rejection of dextran and 90% of flux recovery ratio. At further addition of PEG400 concentration, irreversible fouling was starting to increase. A 90% of irreversible fouling was formed in the PVC membrane when more than 22 wt.% of PEG400 is added.

The Effect of Hoichunyanggyuksan on the Anti-allergic Effect, Analgesic Action, Anti-inflammatory Action and Antipyretic Action. (回春凉膈散이 抗알레르기 및 消炎, 鎭痛, 解熱效果에 미치는 影響)

  • Kim Gyung Jun;Kim Joong Ho;Chae Byung Yoon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.7 no.1
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    • pp.1-13
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    • 1994
  • The Effects of Hoichunyanggyuksan on the Anti-allergic Effect, Analgesic Action, Anti-inflammatory Action and Antipyretic Action. Experimental studies were done to research the clinical effects of Hoichunyanggyuksan on the Anti-allergic effect, Analgesic action, Anti-inflammatory action and Antipyretic action. The results obtained as follows; 1. On vascular permeability responses to intradermal histamine, Hoichnyanggyuksan showed significant effect. 2. In the homologous PCA provoked by the IgE-like antibody against white egg albumin, Hoichunyanggyuksan showed the decreasing tendency, but was none significant effect. 3. In the delayed type hypersensitivity responses to Picryl chloride, Hoichunyanggyuksan was proved significant effect. 4. In the delayed type hypersensitivity resposes to SRBC, Hoichunyanggyuksan revealed significant effect. 5. In Anti-pyretic action by yeast method, Hoichunyanggyuksan showed significant effect. 6. In Anti-inflammatory action by carrageenin method, Hoichunyanggyuksan showed significant effect. 7. In analgesic action by acetic acid method, Hoichunyanggyuksan was recognized significantly.

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Characteristics of High Early Strength Latex Modified Sprayed-Mortar (조강형 라텍스개질 스프레이 모르타르의 특성)

  • Yun, Kyong-Ku;Lee, Bong-Hak;Lee, Jin-Beom
    • Journal of Industrial Technology
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    • v.33 no.A
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    • pp.93-99
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    • 2013
  • Shotcrete has been referred to as gunite, pneumatically applied mortar or concrete, sprayed concrete or mortar. There are sound reasons why sprayed mortar is one of the best portland cement based material for repairing old concrete structures. However, it is difficult to find the research results on the latex-modified mortar nevertheless on the impact of air onto the fresh and hardened properties of latex-modified mortar. So, the main experimental program included strength test, slump test, rapid chloride permeability test, image analysis for air void system, and chemical attacks with the main experimental variables of latex content, fine aggregate content, water-cement ratio, and air foamer content.

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Development of Novel Polymeric Sunscreen Agent

  • Hyo-Joong Kim;Hye
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.22 no.2
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    • pp.89-98
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    • 1996
  • A novel polymeric sunscreen agent was developed. It was prepared by the coupling reaction of 2-ethylhexyl 4-hydroxycinnamate with poly vinylbenzyl chloride(PVBC, average MW 6,500). In this reaction the reactivity was mostly affected by catalyst. In the absence of catalyst the yield was approximately 55% and in the presence of tetrabutylammonium bromide the yield was about 65%, but in the presence of tetrabutylammonium iodide the yield was 100% to give a average molecular weight 20,000 polymeric sunscreen agent. There were no side reactions, and its structure and purity were confirmed by various analytical methods, such as NMR, IR, and so on. UV radiation absorption efficiency is more than 70% compared with that of octyl methoxycinnamate. The solubility in polar oil, for example C12-15 alkylbenzoate and caprylic/capric triglyceride, is more than 50%. It showed high stability in the time course of test including acceleration test. This polymer is safe to skin because of poor permeability to skin, no side products in the process of preparing, and easy elimination of excess starting materials.

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Assessment on Durability of Ultra-High Strength Cementitious Composites (초고강도 시멘트 복합체의 내구성 평가)

  • Park Jung Jun;Kang Su Tae;Ryu Gum Sung;Lee Jong Suk;Koh Kyung Taek;Kim Do Gyum
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.313-316
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    • 2004
  • In this paper, it was assessed durability of ultra-high strength cementitious composites(UHSCC) with the range of 180MPa of compressive strength through the test method of chloride ion resistance, carbonation, freezing-thawing resistance, permeability. In order to compare with ultra-high strength cementitious composites, normal concrete and high-strength concrete were also tested. As the experimental result, it showed that UHSCC was cleary superior to the durability performance of normal concrete and high-strength concrete.

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Evaluation of Durability Performance of Wet- Mixed Shotcrete with Powder Types Cement Mineral Accelerator (시멘트 광물계 급결제를 사용한 습식 숏크리트의 내구성 평가)

  • Won Jong-Pil;Sung Sang-Kyoung;Park Chan-Gi;Cho Yong-Jin;Choi Seok-Won;Park Hae-Geun
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.253-256
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    • 2004
  • Recently, construction works of scale are getting larger with economic growth. Shotcreting is one of major processes in tunnels construction. Accelerator is used in tunnel and underground structures to ensure early strength of shotcrete. Silicate based accelerator and aluminate based accelerator is getting widely in the field. But these accelerators have many problems due to decesase of long-term strength and low quality of the hardened shotcrete. in order to solve these problems, recently developed powder types cement mineral accelerator. In this study, we tested chloride permeability, freezing and thawing and accelerated carbonation of shotcrete. As a result of the test, wet-mixed shotcrete with powder types cement mineral accelerator exhibited durability improvement compared to the conventional shotcrete accelerator.

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The Effect of Cholesterol on the Property of Vesicle (Vesicle의 성질에 대한 콜레스테롤의 효과)

  • Cho, Iw-Han;Moon, Kwon-Gi;Shin, Jae-Sup
    • Journal of Pharmaceutical Investigation
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    • v.23 no.1
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    • pp.33-39
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    • 1993
  • Polymerized vesicles were prepared from monomeric cholesterol-containing surfactant. These vesicles were used to extract the free cholesterol. To introduce spacer group into [cholesteryloxycarbonylmethyl] [2-(methacryloyloxy)ethyl]dimethylammonium chloride (CHODAMA), [5-[ (cholesteryloxy)carbonyl]pentyl] [2-(methacryloyloxy)ethyl]dimethylammonium bromide (CHODAMA-5) and [10-[(cholesteryloxy)carbonyl]decyl] [2-(methacryloyloxy)ethyl]dimethylammonium bromide (CHODAMA-10) were synthesized, In both case of polymerized vesicle with CHODAMA-5 and CHODAMA-10, the permeability was decreased and the amount of extracted cholesterol was also decreased, compared with the polymerized vesicle of CHODAMA.

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Physical Properties of Chitosan Film made from Crab Shell (꽃게 껍질에서 분리제조한 키틴산 필름의 물성에 관한 연구)

  • Cho, Jeong-Suk;Han, Jeong-Jun;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.24 no.6
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    • pp.574-580
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    • 1992
  • Chitin was isolated from the residue of enzymatically hydrolyzed crab, Portunus trituberculatus, and further deacetylated by alkaline boiling to make chitosan. The physical properties of chitosan solution and its film forming properties were examined. The functional characteristics of chitosan film were compared to those of cellophane, polyvinyl chloride (PVC) and polyethylene (PE) films. The proximate chemical composition of chitin obtained from crab residue was 6.95% nitrogen, 0.3% crude ash and 4.57% moisture and the product yield was 12.8% based on a dry material basis. The degree of deacetylation of chitosan was $79{\sim}92%$ and $70{\sim}86%$ as determined by IR spectroscopy, and $70{\sim}86%$ as determined by colloid titration method each respectively. The chitosan at 1% acetic acid solution showed distinct pseudoplastic flow behavior. The flow behavior index and consistency index were 0.8886, 0.2084 $MPa{\cdot}s^n$ for 0.4% solution and 0.8498, 0.6190 $MPa{\cdot}s^n$ for 0.8% solution, respectively. The chitosan film had the highest tensile strength $(888 kg/cm^2)$ and water permeability $(100\;g/m^2{\cdot}24\;hrs)$ among the tested films, but relatively low elongation property (49%). It showed the similar tear strength (90kg/cm) and light permeability (87.7%) to other films tested in spite of the relatively high haze value (12.5%). As the thickness of chitosan film increased from 0.025 to 0.050 mm, the tensile strength of film decreased distictively, and the degree of elongation, tear strength, and water permeability of film also decreased slightly. Whereas the light permeability of film did not change and the haziness of film slightly increased by the increase of film thickness.

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Resistance of Chloride Penetration into High Strength Concrete Containing Mineral Admixtures according to Curing Conditions (광물질혼화재 혼합 고강도콘크리트의 양생조건에 따른 염화물이온 침투저항성)

  • Moon, Han-Young;Kim, Byoung-Kwon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.8 no.2
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    • pp.185-194
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    • 2004
  • In recent years, construction company makes inroads into the world construction market, and receives the order of extra-large concrete structure under marine environment in south-east asia specially. At this point of time, to enhance the quality of concrete, we research the High Strength Concrete (HSC) containing mineral admixtures. In this study, therefore, HSC with various combination of ordinary portland cement(OPC), blast-furnace slag(SG), silica fume(SF), and expansion admixture(SS) are cured 23 and $35^{\circ}C$ considering the site weather, and are cured in water for 3, 7 or 56 days respectively. Test results show that the HSC cured at $35^{\circ}C$ gains higher early-age strength but eventually gains lower later-age strength compare with the HSC cured at $23^{\circ}C$. Especially, HSC with combination of OPC+SG+SF+SS or OPC+SG+SF show very excellent resistance of chloride penetration. The permeability of HSC was therefore enhanced as because of containing the proper content of SG, SF, and SS and making dense micro-structure of HSC.

Effect of zinc oxide nanoparticle types on the structural, mechanical and antibacterial properties of carrageenan-based composite films (산화아연 나노입자 유형이 카라기난 기반 복합 필름의 구조, 기계적 및 항균 특성에 미치는 영향)

  • Ga Young Shin;Hyo-Lyn Kim;So-Yoon Park;Mi So Park;Chanhyeong Kim;Jae-Young Her
    • Food Science and Preservation
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    • v.31 no.1
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    • pp.126-137
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    • 2024
  • In this study, zinc oxide nanoparticles (ZnONPs) were synthesized using three distinct zinc salts: zinc acetate, zinc chloride, and zinc nitrate. These ZnONPs were subsequently utilized in the fabrication of carrageenan-ZnONPs (Car-ZnONPs) composite films. The study assessed influence of the various ZnONPs on the morphological, water vapor barrier, color, optical, and antimicrobial properties of the Car-ZnONPs composite films. The surface morphology and UV-blocking attributes of the composite films were affected by the type of ZnONPs used, but their surface color, transparency, and chemical structure remained unaltered. The composite film's thickness and elongation at break (EB) significantly increased, while the tensile strength significantly decreased. In contrast, film's elastic modulus (EM) and water vapor permeability coefficient (WVP) showed no significant difference. All the composite films with added ZnONPs demonstrated potent antibacterial activity against Escherichia coli O157:H7 and Listeria monocytogenes . Among the carrageenan-based composite films, Car-ZnONPsZC showed the highest antibacterial and UV-blocking properties, and its elongation at break was significantly higher than that of the pure carrageenan films. This suggests that ZnONPs composite films have the potential to be used as an active packaging film, preserve the safety of the packaged food and extend shelf life.