• Title/Summary/Keyword: 물리 화학적 특성

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Physical and Chemical Properties of Waste Glass as Feed Materials for the Production of Foamed Glass (발포유리 원료로서 폐 유리의 물리 화학적 특성)

  • Lee, Chul-Tae
    • Applied Chemistry for Engineering
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    • v.16 no.3
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    • pp.440-448
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    • 2005
  • Physical and chemical properties of waste glass, such as bottle glass, plate glass, and LCD glass were investigated to test the feasibility of starting materials for the production of high quality foamed glass for insulating grade construction material without pre-treatments such as cleaning, and waste removals. For this purpose, chemical analysis, thermal analysis, crystalline analysis, and rheological analysis including viscosity were proceeded and the preparation of foamed glass under the qualitative conditions obtained from these various analysis was also attempted. Overall results of various analysis and investigations for these waste glass showed that waste bottle glass and plate glass have high possivility of use as feed materials for the production of foamed glass.

Pensky-Martens 측정 장치를 이용한 n-Propanol-n-Propionic Acid 계의 인화점

  • 최용찬;이성진;하동명
    • Proceedings of the Korean Institute of Industrial Safety Conference
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    • 2002.11a
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    • pp.178-183
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    • 2002
  • 화학공정설계에 있어 온도, 압력, 농도 등에 대한 운전 범위와 반응물, 중간생성물, 생성물 및 부산물에 대한 물성치인 물리적 및 화학적 특성, 안전성, 독성 등을 파악하는 것이 무엇 보다 중요하다. 공정상에서 가연성물질의 생산, 처리, 수송, 저장할 때 취급 부주의로 화재 및 폭발이 야기될 수 있다. 따라서 가연성물질의 안전한 취급을 위해서는 이들 물질의 중요한 기초적인 안전특성(safety property) 자료인 인화점(flash point)에 대한 지식을 필요로 한다.(중략)

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Effect of green tea supplementation on probiotic potential, physico-chemical, and functional properties of yogurt (요구르트의 프로바이오틱 활성과 물리화학적 및 기능적 특성에 대한 녹차 추출물의 영향)

  • Lim, Eun-Seo
    • Korean Journal of Microbiology
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    • v.53 no.2
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    • pp.103-117
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    • 2017
  • The aim of this study was to evaluate the effect of green tea extract on probiotic potential, physico-chemical and functional properties of yogurt fermented with Lactobacillus acidophilus D11 or Lactobacillus fermentum D37 strains isolated from Doenjang. Probiotic activities such as the resistance to artificial digestive juices and the ability to adhere to epithelial cells were slightly higher in yogurt supplemented with green tea extract than in plain yogurt, which may be attributed to the increase in the number of lactic acid bacteria (LAB) by green tea extract supplementation. Furthermore, the microbiological and physico-chemical properties such as the number of LAB, organic acid production and viscosity were significantly (P<0.05) increased in yogurt added green tea extract compared to plain yogurt fermented with L. acidophilus D11. However, the green tea extract did not significantly (P>0.05) affect these properties of yogurt fermented with L. fermentum D37 strain. Meanwhile, the antibacterial activities against Escherichia coli O157 ATCC 43889, Salmonella enteritidis ATCC 13076, and Salmonella typhimurium KCTC 2514 and antioxidant activities including total phenol content, radical scavenging ability, and ferric-reducing antioxidant power were significantly higher in plain yogurt fermented with L. fermentum D37 than with L. acidophilus D11. The antibacterial and antioxidant activities of the yogurt were significantly (P<0.05) increased in proportion to the concentration of green tea extract added to plain yogurt. Consequently, green tea yogurt fermented with L. acidophilus D11 or L. fermentum D37 was considered to be a useful functional food that can inhibit the growth of pathogenic bacteria and scavenge the free radicals from the body cells.

Physicochemical Properties and Growth Characteristics of Wood Chip and Peat Moss Based Vegetation Media (우드칩과 피트모스를 원료로 하는 식생기반재의 물리·화학적 특성 및 생육 특성)

  • Kim, Ji-Su;Jung, Ji Young;Ha, Si Young;Yang, Jae-Kyung
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.3
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    • pp.323-336
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    • 2016
  • This study was carried out to evaluate the physicochemical properties of steam exploded wood chips for peat moss substitute in vegetation media. Also, the mixtures at the different ratios of peat moss and pretreated wood chips (90 : 10, 70 : 30 and 50 : 50 (w/w), respectively) were evaluated by physicochemical and plant growth characteristics. The pretreated wood chips was showed that bulk density, porosity and pH were $0.26g/cm^3$, 93.3% and 5.7, respectively. This result indicates that physicochemical properties was improved when wood chips was apply to steam explosion in the range of optimum physicochemical condition for vegetation media. In particular, the mixture ratio of peat moss and pretreated wood chips to 70 : 30 (w/w) showed higher seed germination, plant height and leaf growth than peat moss. Also, the bulk density, porosity, water holding capacity, pH and C/N ratio were $0.20g/cm^3$, 91.8%, 76.1%, 5.2 and 51.0 in the range of optimum physicochemical condition for vegetation media.

Interaction Experiment on Chloride Ion Adsorption Behavior of C-S-H Phases (C-S-H 상의 염소이온 흡착 메커니즘 규명을 위한 반응 작용 실험)

  • Yoon, In-Seok
    • Journal of the Korea Concrete Institute
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    • v.29 no.1
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    • pp.65-75
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    • 2017
  • C-S-H phase is the most abundant reaction product, occupying about 50~60% of cement paste volume. The phase is also responsible for most of engineering properties of cement paste. This is not because it is intrinsically strong or stable, but because it forms a continuous layer that binds together the original cement particles into a cohesive whole. The binding ability of C-S-H phase arises from its nanometer-level structure. In terms of chloride penetration in concrete, C-S-H phase is known to adsorb chloride ions, however, its mechanism is very complicated and still not clear. The purpose of this study is to examine the interaction between chloride ions and C-S-H phase with various Ca/Si ratios and identify the adsorption mechanism. C-S-H phase can absorb chloride ions with 3 steps. In the C-S-H phase with low Ca/Si ratios, momentary physical adsorption could not be expected. Physical adsorption is strongly dependent on electro-kinetic interaction between surface area of C-S-H phase and chloride ions. For C-S-H phase with high Ca/Si ratio, electrical kinetic interaction was strongly activated and the amount of surface complexation increased. However, chemical adsorption could not be activated for C-S-H phase with high Ca/Si ratio. The reason can be explained in such a speculation that chloride ions cannot be penetrated and adsorbed chemically. Thus, the maximum chloride adsorption capacity was obtained from the C-S-H phase with a 1.50 Ca/Si ratio.