• Title/Summary/Keyword: absorption ratios

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The Influences of Cement Mortar Replaced by Paper Sludge Ash and Blast Furnace Slag (제지 슬러지 애쉬 고로슬래그 미분말로 혼합치환한 시멘트가 모르타르에 미치는 영향)

  • 소병현;이주나;박찬수
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.10a
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    • pp.3-9
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    • 2002
  • Paper sludge ash was assured as material of a sort of pozzolan. For the reason of fluidity decrease caused by the strong absorption of paper stooge ash and the decrease of compressive strength in case of using over30% replacement by the weight of cement, paper sludge ash is not suitable for blending material. Therefore, it is necessary to find proper replacement ratios between paper sludge and blast furnace slag to insure compressive compensation and appropriate slump. Accordingly, as varied the blending ratios of paper sludge and blast furnace slag, testing mortar was made. This study was aimed to investigate the possibility of using blending replacement of paper sludge ash and blast furnace slag throughout compressive test, flow test, SEM(Scanning Eletron Microscope), MIP(Mercury Intrusion Porosity test), and TG-DTA(Thermal analysis).

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An Experimental Study on the Fundamental Properties of Electric Pole Recycled Aggregate(EPRA) and Characteristics of High Strength Concrete by Replacement Ratios of EPRA (폐전주 재생골재의 기초물성 및 대체율에 따른 고강도영역 재생골재 콘크리트의 특성에 관한 실험적 연구)

  • 이강우;이종호;강석표;최세진;최희용;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.05a
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    • pp.495-500
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    • 2001
  • In this study, it was analized and examined fundamental properties of Electric Pole Recycled Aggregate(EPRA) and hardened properties & chemical resistance with H$_2$SO$_4$by replacement ratios of EPRA, and the results are as follows 1) In the case of electric pole recycled coarse aggregate, All fundamental properties are better than that of normal recycled aggregate and both water absorption and amount of crushed loss are with level of natural aggregate 2) As the replacement ratio of electric pole recycled fine aggregate is increased strength development is decreased. but in the case of coarse aggregate, that of it is with level of natural aggregate 3) As the replacement ratio of electric pole recycled fine aggregate is increased chemical resistance is decreased. but in the case of coarse aggregate, that of it is with level of natural aggregate

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Rheological Properties of Dough Added with Wheat Bran (밀기울 첨가 반죽의 물리적 특성)

  • 김영호
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.6
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    • pp.1125-1131
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    • 1998
  • The rheological properties of wheat flour dough were investigated in the dough added with 0, 10, 15, 20, 25 and 30% of wheat bran. The ratios of ash contents in wheat flour and wheat bran were 0.43% and 5.28%, respectively. The ratios of fiber contents in wheat flour and wheat bran were 0.18% and 11.86%, respectively. The farinograph water absorption was increased as the amount of wheat bran was increased. Both arrival time and development time of the dough added with wheat bran were longer than those of wheat flour. As the amount of wheat bran was increased, the weakness was increased. The extensograph showed that extensibility and resistance to extension of dough were decreased, while the ratio of resistance to extensibility(R/E) was increased with increasing the amo unt of wheat bran. The maximum viscosity by amylograph was decreased gradually with the adding amount of wheat bran, while the gelatinization temperature was slightly increased with wheat bran.

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X-ray CT monitoring of macro void development in mortars exposed to sulfate attack

  • Tekin, Ilker;Birgul, Recep;Aruntas, Huseyin Y.
    • Computers and Concrete
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    • v.21 no.4
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    • pp.367-376
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    • 2018
  • This study reports the results of nondestructive monitoring of macro void developments in mortars manufactured with both ordinary Portland cement and sulfate resistant cement. Two types of curing were utilized; tap water curing and another curing environment that contains 5% $Na_2(SO_4)$ solution. Being the primary objective of this study, macro void developments of the mortar specimens were monitored by X-ray Medical Computerized Tomography. Compressive strength tests and water absorption tests were conducted on specimens that were kept in both curing environments for a duration of 560 days. Data analyses yielded consistent results among the three tests used in this experimental study. Macro void ratios of mortars decreased at the beginning of experiments for a certain period; afterwards, macro void ratios increased. The objective of this study was accomplished as anticipated since X-CT image analysis was able to nondestructively monitor macro void development process in cement mortars.

Effects of Condensed Phosphates on the Quality and Self-life of Wet Noodle (중합인산염이 생면의 품질 및 저장성에 미치는 영향)

  • 김진성;손종연
    • Korean journal of food and cookery science
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    • v.20 no.2
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    • pp.133-137
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    • 2004
  • This study was investigated the effects of condensed phosphates (pyrophosphate, metaphosphate and polyphosphate) on the quality and self-life of wet noodle. The initial pasting temperatures were increased by the addition of pyrophosphate and metaphosphate, respectively, whereas those of propylene glycol and polyphosphate were decreased. Pyrophosphate showed the highest final viscosity, whereas metaphosphate showed the lowest. Setback of PG, polyphosphate, pyrophosphate and metaphosphate were all lower than the control. The water absorption ratios of PG and polyphosphate were increased compared to the control, whereas those of pyrophosphate and metaphosphate were decreased. The volume expansion ratios of PG and polyphosphate were slightly increased. Turbidities of PG and polyphosphate were lower than those of the control, whereas those of pyrophosphate and metaphosphate were increased in cooked noodles. The bacterial counts of wet noodles made with PG, polyphosphate, metaphosphate and pyrophosphate were all lower than those of the control after storage at 5$^{\circ}C$.

Thermodynamic Analysis of a Double-Effect Absorption Heating System Using Water-LiCl-$CaCl_2-Zn(NO_3)_2$ Solution at Solar Evaporator Heating (LiCl-$CaCl_2-Zn(NO_3)_2$ 수용액을 사용하는 흡수 2중효용 시스템에서 태양열을 증발기 열원으로 사용하는 난방기의 열역학적 해석)

  • Won, Seung-Ho
    • Journal of the Korean Solar Energy Society
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    • v.27 no.3
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    • pp.87-94
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    • 2007
  • In this paper, with water-LiCl-$CaCl_2-Zn(NO_3)_2$ mixture which utilizes solar energy at the evaporator heat source, a thermodynamic analysis was performed to provide design data for a double-effect absorption heating system. A comparative study of the water-LiCl-$CaCl_2-Zn(NO_3)_2$ mixture against the water-LiBr pair was conducted by a computer simulation. The computer simulation is based on mass, material and heat balance equations for each part of the system. Coefficients of performance and flow ratios for effects of different operating temperatures are investigated. It is found that the heating COP is higher for the water-LiCl-$CaCl_2-Zn(NO_3)_2$ mixture than for the water-LiBr pair, and FR is lower for the former.

Thermodynamic Analysis of a Double-Effect Absorption Heating System Using Water-LiBr- LiSCN Solution As $20{\sim}40^{\circ}C$ Range Solar Evaporator Heating (태양열을 증발기 열원으로 사용($20{\sim}40^{\circ}C$범위)하며 LiSCN+LiBr 수용액을 사용하는 흡수식 2중효용 난방시스템의 열역학적 해석)

  • Won, Seung-Ho
    • Journal of the Korean Solar Energy Society
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    • v.26 no.4
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    • pp.73-81
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    • 2006
  • In this paper, with water-LiBr-LiSCN mixture which utilizes solar energy as mid temperature range evaporator heat source, a thermodynamic analysis was performed to provide design data for a double-effect absorption heating system. A comparative study of the water-LiBr-LiSCN mixture against the water-LiBr pair was conducted by a computer simulation. The computer simulation is based on mass, material and heat balance equations for each part of the system. Coefficients of performance and flow ratios for effects of different operating temperatures are investigated. It is found that the heating COP is higher for the water-LiBr-LiSCN mixture than for the water-LiBr pair, and FR is lower for the former.

Highly Luminescent Aniline and TiO2 Composite: The Effect of Weight Ratio of Aniline and TiO2

  • Kim, Byoung-Ju;Park, Eun-Hye;Kang, Kwang-Sun
    • Current Photovoltaic Research
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    • v.4 no.1
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    • pp.8-11
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    • 2016
  • Strong deep ultraviolet emitting aniline and $TiO_2$ composite has been synthesized via hydrolysis and condensation reactions of titaniumisopropoxide ($Ti(OPr)_4$), aniline, and acetic anhydride. Three different weight ratios of aniline and $Ti(OPr)_4$ including 3:1 ($TiO_2An-A$), 2:1 ($TiO_2An-B$), and 1:1 ($TiO_2An-C$) were synthesized and characterized their optical properties. The FTIR spectra of the $TiO_2An-A$, -B, and -C showed the absorption intensities of the benzene ring stretching and bending vibrations, and benzene ring -CH stretching, bending, and deformation vibrations increased with the increase of the amount of aniline. The UV-visible absorption spectra showed that the UV region absorption was slightly increased with the increase of the amount of aniline. The photoluminescence (PL) intensities were exponentially increased with the increase the excitation wavelength from 307 to 317 nm, steadily increased from 300 to 313 nm and slowly increased from 302 to 308 nm for $TiO_2An-A$, -B, and -C, respectively and decreased thereafter. Therefore, the PL intensity is strongly dependent on the weight ratio of $Ti(OPr)_4$ and aniline.

Mass transfer characteristics of benzene in nonpolar solution (비극성용매 내의 벤젠 물질전달특성)

  • 최성우;김혜진;박문기
    • Journal of Environmental Science International
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    • v.11 no.6
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    • pp.605-610
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    • 2002
  • The absorption of benzene in nonpolar solution was studied in a laboratory-scale of bubble column varying of gas flow rates and gas-to-liquid ratios. A bubble column had a 0.8∼l$\times$10$\^$-3/ m$^3$ total volume (height 1500 mm, diameter 50 mm). Solution analysis was performed by GC-FID and GC-MSD. The objectives of this research were to select the best absorption fluid and to evaluate the mass transfer characteristics under specific conditions of each absorption. The results of this research were follow as: First, the heat transfer fluid is more efficient than the other nonpolar solution in removing VOC. Second, The benzene removal efficiency improved according to an increasing rate of gas flow. Also, volumetric mass transfer rate of column can be enhanced by increasing gas flow rate. Finally, the relation of gas flow rates, liquid amount, and volumetric mass transfer coefficient was obtained as follows. K$\_$y/a: 0.5906(V$\_$g//L)$\^$0.7611/ The following correlation of mass transfer coefficient and efficiency was proposed. v= 0.06078 K$\_$y/a$\^$0.2444/.

A Study on Smart Heat Radiating Sheet for Protecting Electronic Equipments on the Ship

  • Choi, Dong-Soo;Kim, Dong-Il;Kim, Doh-Yeol;Choi, Dong-Han;Kil, Gyung-Suk;Kim, Jae-Hwan
    • Journal of Navigation and Port Research
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    • v.35 no.7
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    • pp.569-573
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    • 2011
  • In this paper, we developed a Smart Heat Radiating Sheet(SHRS) having the absorption ability of more than 15 dB, and thermal conduction rate more than 20 W/mk for port logistics RFID(Radio Frequency IDentification) system by using AMP(Amorphous Metal Powder) and shielding sheet. Firstly, the EM(Electro_Magnetic) wave absorber samples were fabricated by using AMP and CPE (Chlorinated Polyethylene) with different composition ratios of 80 : 20 wt.% and 85 : 15 wt.%, respectively. Secondly, we fabricated the Smart Heat Radiating Sheet using the shielding sheet to attach EM Wave Absorber. As a result, the Smart Heat Radiating Sheet with absorption ability of 16 dB at 433 MHz and thermal conduction rate is 24 W/mk has been developed with the composition ratio of Amorphous Metal Powder : CPE = 85 : 15 wt.% and thickness of 5.5 mm.