• Title/Summary/Keyword: mixed ratio

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An Experimental Study on The Effect of Mixed Sand Used Sea and River Sand as Fine Aggregate of Concrete (해사와 강모래의 혼합재를 사용한 콘크리트에 관한 실험적 연구)

  • 남상일;김문한;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • 1992.10a
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    • pp.31-36
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    • 1992
  • This paper, an experimental study on the effect of mixed sand used sea and river as fine aggregate of concrete, is connected with the properties of fresh and hardended concrete and steel corrosion to investigate workability and engineering properties and general steel bar's corrosion of concrete used mixed sand. After analyzing positively fresh and hardenend concrete and ratio of the corrosion area affected by the autoclave cycle, the purpose of this paper is to provide an experimental data developing concrete used mixed sand.

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A Study on the Electrical Properties of Organic Miked Films (유기혼합막의 전기특성에 관한 연구)

  • 조수영;이경섭
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.503-506
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    • 2000
  • Molecular switching in azobenzene mixed monolayers on a water surface was investigated by means of Maxwell displacement current(MDC) measurement. It was found that the change in the vertical component of the dipolemoment of the mixed monolayer during visible light irradiation was almost the same as that flowing during UV light irradiation. Also MDC was generated but it depended on the molar ratio. As a result. It's phtoisomerization progressed by 8A5H in mixed films.

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Detergency of Particulate Soil in Anion/Nonionic Surfactant Mixed Solution (음이온/비이온 혼합 계면활성제 용액에서의 고형오구의 세척성)

  • Kang, In-Sook
    • Fashion & Textile Research Journal
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    • v.13 no.5
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    • pp.790-796
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    • 2011
  • This study was designed to investigate the influence of ratio of anionic/nonionic surfactant mixture on detergency of particulate soil under various solutions. The detergency of the particulate soil was determined by adhesion of particle to fabric and its removal from fabric separately. The PET fabric and ${\alpha}-Fe_2O_3$were used as materials of textile and model of particulate soil, respectively. The detergency was investigated as a function of surfactants concentration, ionic strength, kinds of electrolyte and mole numbers of oxyethylene ether of nonionic surfactant in different ratio of anionic/nonionic surfactant mixture. Although some deviations exist, the adhesion of particle to fabric generally increased with decreasing its removal from fabric. The detergency of particulate soil on PET fabric was relatively higher in anionic/nonionic surfactant mixed solution than in each single surfactant solution, but the influence of ratio of anionic/nonionic surfactant mixture on detergency of particulate soil was low. Generally the detergency of particulate soil on fabric was at its maximum at 0.1% surfactant concentration, $1{\times}10^{-3}$ ionic strength, $Na_5P_3O_{10}$ electrolytes and 10 mole numbers of oxyethylene ether of nonionic surfactant, regardless of ratio of anionic/nonionic surfactant mixture.

Nonlinear Dynamic Properties of Fiber Reinforced Soils (섬유혼합토의 비선형 동적물성치)

  • 박철수;황선근;목영진
    • Journal of the Korean Geotechnical Society
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    • v.19 no.2
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    • pp.189-197
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    • 2003
  • In this paper, deformation characteristics of fiber-mixed-soils were studied at small strain range(0.0001%~1%) using resonant column test and triaxial test, and reinforcement effect was evaluated by the measure of maximum shear moduli. The effects of the major parameters such as fiber content, aspect ratio and fiber type on reinforcement were comparatively assessed. The specimens were remolded from Jumunjin Sand randomly mixed with discrete polypropylene staple fibers. Maximum shear moduli of fiber-mixed-soils increased by up to 30% and modulus reduction was also restrained in nonlinear range. Shear moduli increased as the aspect ratio increases. The reinforcement was more effective with fibrillated fiber than with monofilament fiber. The most effective reinforcement was achieved with the specimen of 0.3 % fiber content.

Effect of Rice Straw Steaming Time and Mixing Ratio between Acacia mangium Willd Wood and Steamed Rice Straw on the Properties of the Mixed Particleboard

  • Tran, Van Chu;Le, Xuan Phuong
    • Journal of Forest and Environmental Science
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    • v.31 no.2
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    • pp.119-125
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    • 2015
  • This study examined the effects of rice straw steaming time and mixing ratio between rice straw and wood particle on the properties of mixed particle board from Acacia mangium Willd wood and rice straw. Rice straw and Acacia mangium Willd wood were collected in Hanoi, Vietnam. The particle board was three-layer particle board with the structural ratio of 1:3:1. The thickness, density and board size of the particle board were 18 mm, $0.7g/cm^3$, and $800{\times}800{\times}18$ (mm, including trimming), respectively. A resin mixture between commercial Urea-formaldehyde (U-F) adhesive and methylene diphenyl isocyanate (MDI) adhesive was used with a dosage of 12% for the core layer and 14% for the surface layer. In this experimental design, the steaming time for rice straw was 15, 30, 45, 60, and 75 minutes at $100^{\circ}C$. The rice straw-wood mixing ratio was 10, 20, 30, 40, and 50%. The results showed that both mixing ratio and steaming time affect the properties of the particleboard, but the mixing ratio has a stronger impact. A higher mixing ratio and a longer steaming time resulted in a better quality of particleboard. The optimal steaming time for rice straw was 46.12 minutes with the straw-wood mixing ratio of 29.85% with the following characteristics of the particle board: the modulus of rupture (MOR) of 14.64 MPa, internal bond strength (IB) of 0.382 MPa, thickness swelling (TS) of 8.83%, and board density of $0.7-0.7g/cm^3$.

Effects on the Application of Popped Rice Hulls Compost as Substitute Material of Yacto in Yang-jik Nursery Bed of Panax ginseng C. A. Meyer (인삼 양직모밭에서 약토 대체를 위한 팽화왕겨퇴비의 시용 효과)

  • Kang, Seung Weon;Lee, Sung Woo;Hyun, Dong Yun;Kim, Jang Wook;Kim, Yong Bum;Lee, Hye Jin;Cha, Seon Woo
    • Korean Journal of Medicinal Crop Science
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    • v.21 no.1
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    • pp.45-48
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    • 2013
  • This study was carried out to know the substitute effect of Yacto (leaf mold compost) on popped rice hulls compost (PRHC) in Yang-jik nursery bed of Panax ginseng. PRHC was mixed with Yacto as 50:50 ratio, and 1 ~ 2% of the mixed oil cake, rice bran and urea were also added to promote decaying the mixed compost. The mixed compost made by PRHC and Yacto was showed that positive effect on the growth of ginseng seedling when it was mixed with 1% of oil cake and rice bran, and 2% of mixed oil cake. But addition to the 2% of urea in the mixture of PRHC and Yacto was not positive effect on the growth of ginseng seedling. Root yield of the mixed compost was similar to that of conventional compost by made 100% of Yacto. Therefore, the mixed compost can substitute for Yacto when PRHC and Yacto were mixed by 50:50 ratio and added 1% of oil cake and rice bran.

Mixed Culture Characteristics of Fungi Strains isolated from Korean Traditional Nuruk (전통누룩에서 분리한 양조용 곰팡이의 혼합 배양에 따른 품질 특성)

  • Mun, Ji-Young;Baek, Seong-Yeol;Ro, Hyeon-Su;Yeo, Soo-Hwan
    • Journal of the East Asian Society of Dietary Life
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    • v.27 no.3
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    • pp.348-363
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    • 2017
  • We analyzed the mixed culture characteristics of isolated brewing fungi obtained from Korean traditional nuruk for their development as fermentation starters. In a previous study, we selected appropriate fungi strains based on their large fungi bodies and strong enzyme activities. These fungi strains were mixed cultured under various combination of ratios, pHs and temperatures. As a result, total acidities of R. delemar mixed culture media were higher than those of A. oryzae cultured at $20^{\circ}C$ and $37^{\circ}C$. The pHs of A. luchuensis 34-1 and A. oryzae 37-7 as well as R. delemar 58-8 and A. oryzae 37-7 mixed culture media gradually increased with the culture period. On the contrary, total acidities of the mixed culture media gradually decreased. ${\alpha}-Amylase$ activities of R. delemar 26-4 and R. oryzae 82-7 mixed culture media were strong at $20^{\circ}C$ and pH 4, glucoamylase activities of R. delemar 58-8 and A. oryzae 37-7 were strong at $37^{\circ}C$, pH 3 and 1:2 ratio, and acidic protease activities of R. delemar 26-4 and A. oryzae 78-5 were strong at $20^{\circ}C$, pH 4 and 1:4 ratio. This study provides the optimal mixed culture conditions for fermentation starters based on changes in pH and total acidity, favorable enzyme activities, and fungi varieties.

Strength and Freezing-Thawing Properties of Recycled aggregate Concrete Mixed Fly Ash (플라이애쉬를 혼합한 재생골재 콘크리트의 강도 및 동결융해 특성)

  • 구봉근;류택은;이재범;양승규
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.10a
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    • pp.241-244
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    • 1999
  • This study is represented the strength and freeing-thawing properties of recycled aggregate concrete mixed fly ash by experiment. The experimental variables are the substitution ratio of recycled aggregate and the mixing ratio of fly-ash. For each specimens, there were tested compressive strength and freeze-thaw resistance. It is able to find from the experimental result that the recycled aggregate concrete has good properties as general concrete on the compressive strength and the durability.

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A Study on thermal cutting characteristics of hydrogen-oxygen mixed gas (수소-산소 혼합가스의 열절단 특성 연구)

  • Kim, Nam-In;Jang, Yong-Won;Jeong, Jun-Sik;Lee, Jeong-Su
    • Proceedings of the KWS Conference
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    • 2007.11a
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    • pp.8-10
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    • 2007
  • In recent years, hydrogen-oxygen mixed gas generated by electrically dissociating water has been proposed as alternative cutting fuel. The mixed gas consists of a hydrogen-oxygen mixed gas in the mixture ratio of 2:1. And gas has some merits as cutting quality and speed compared with existing gas cutting process. Because main source of mixed gas is water, mixed gas is environmental-friendly clean fuel. The purpose of the present paper is to investigate cutting characteristics and optimum cutting parameters of mixed gas, The effect of cutting parameter on the cutting characteristics of mixed gas is also investigated as compared to existing gas cutting process.

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Effects of the Feeds Mixed with Various Level of Lard, Perilla Oil and Evening Primrose Oil on Fatty Acid Compositions of Serum Lipid and Lipoprotein in Rats (돈지, 들깨유 및 달맞이꽃 종자유의 혼합급이가 흰쥐의 혈청 및 혈청 지단백의 지방산 조성에 미치는 영향)

  • 김성희;김한수;김희숙;김군자;최운정;정승용
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.23 no.4
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    • pp.548-554
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    • 1994
  • In order to observe the effects of the feeds mixed with the lard and two vegetable seed oils on the fatty acid compositions of serum lipkid and lipoprotein, the oils mixed with 2.5% lard and various levels of perilla oil and evening promrose oil were administered to the male rats of the Sprague-DAwley for 4 weeks. In the fatty acid compositions of serum lipid and serum lipoprotein fractions, as the content so f mixed perilla oil decreased and the contents of mixed evening primrose oil increased, n -3 PUFa (polyunsaturated fatty acid) contents and ratio of EPA/AA (eicisapentaenoiidacid/arachidonic acid) tended to decrease, but n-6 PUFA contents and ratio of AA/PUFA tended to increase. Fatty acid compositions of serum lipid and serum lipoprotein fractions were influenced from the fatty acid composition of the test lipids.

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