• Title/Summary/Keyword: Powder characteristic

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An Analysis of Change on the Apartment Unit Plans and the Interior Spaces Related to Women (여성관련 공간을 중심으로 본 서울지역 아파트의 공간구조 변화)

  • Choi, Byung-Sook;Park, Jung-A
    • Journal of the Korean housing association
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    • v.20 no.4
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    • pp.39-47
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    • 2009
  • The purpose of this study is to find out the changes on the metropolitan condominium apartment unit plans based on the interior spaces related to women such An-bang (master bedroom), bathroom and attached spaces to the master bedroom, living room, diningroom, kitchen, utility room, and balcony. This study used the content analysis method and space syntax. Contents were limited to the floor plans with 3 rooms type and about 105 m2 in the Korean apartment encyclopedia. The unit plans of 2,278, built from October 1975 to January 2008, were analyzed and basically SPSS package 16.0 was employed. The results were as followed. 1) Living room was a core space and an increasing tendency. After 2001, the design trend of living room connected with kitchen and dining room, and dining room changed into one space combining with women's working space such kitchen. It meaned women's working activities became into family public activities as to depending open access. 2) Kitchen had a characteristics that was connected to utility room or back balcony, and the number of extra kitchen increased. Also, the size of DK decreased, but utility size little increased. It was showed the characteristic of this space was still for women. 3) An-bang had a little strong characteristics of married coulpe or women's personal space with bathroom or dress room/powder room. 4) In addition, the values of integration and control of living room and DK were highest. It meant these space were centered in unit plans. Next, the An-bang and dress room/powder room were high. Utility room or balcony's were next, and these were women's working space. Therefore, family's public space was most important, and married couple or women's personal and working space were later in planning.

Development of bone scaffold using HA(Hydroxyapatite) nano powder (HA(Hydroxyapatite) 나노 입자를 이용한 bone scaffold의 개발)

  • Kim J.Y.;Lee S.J.;Lee J.W.;Kim Shin-Yoon;Cho D.W.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.159-160
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    • 2006
  • A novel approach to the manufacture of biocompatible ceramic scaffold for tissue engineering using micro-stereolithography system is introduced. Micro-stereolithography is a newly proposed technology that enables to make a 3D micro structure. The 3D micro structures made by this technology can have accurate and complex shape within a few micron error. Therefore, the application based on this technology can vary greatly in nano-bio fields. Recently, tissue-engineering techniques have been regarded as alternative candidate to treat patients with serious bone defects. So many techniques to design and fabricate 3D scaffolds have been developed. But the imperfection of scaffold such as random pore size and porosity causes a limitation in developing optimum scaffold. So scaffold development with controllable pore size and fully interconnected shape have been needed for a more progress in tissue engineering. In this paper, bone scaffold was developed by applying the micro-stereolithography to the mold technology. The scaffold material used was HA(Hydroxyapatite) nano powder. HA is a type of calcium phosphate ceramic with similar characteristic to human inorganic bone component. The bone scaffold made by HA is expected, in the near future, to be an efficient therapy for bone defect.

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The Effect of Current and Preheat Temperature on Structure and Hardness of Stellite 12 Alloy Overlayer by PTA Process (PTA법에 의한 스텔라이트 12 합금 육성층의 조직과 경도에 미치는 전류와 예열온도의 영향)

  • Jung, B.H.;Kim, M.G.;Kim, G.D.;Kim, M.Y.;Lee, S.Y.
    • Journal of the Korean Society for Heat Treatment
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    • v.13 no.4
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    • pp.246-252
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    • 2000
  • Stellite 12 alloy-powder was overlaid on 410 stainless steel valve seat using plasma transferred arc(PTA) process. Variation of characteristic of microstructure and hardness of deposit with current(90~150 A) and preheat temperature(R.T.~$400^{\circ}C$) was investigated. Important conclusion obtained are as follows; All welding conditions used produced a sound deposit layer with no defect in single pass welding. The maximum deposit had 4.0~4.8 mm in thickness and its bead width was increased with increase of current and preheat temperature. The deposit showed hypoeutectic microstruture, which was consisting of primary cobalt dendrite and networked $M_7C_3$ type eutectic carbides. The amount of eutectic carbides was decreased and its dendritic secondary arm spacing was increased with increase of current. Hardness of the deposit was decreased with increase of current. Preheat temperature up to $400^{\circ}C$, however, showed little influence on the hardness and microstructure. The hardness was also influenced by diluted Fe content near the interface in addition to microstructure and dendritic secondary arm spacing. Hot hardness at $500^{\circ}C$ showed higher than 300 HV.

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Characteristic Evaluation of the Fe-Al Alloy Preform Fabrication by Reactive Sintering Process for the Al Matrix Composites. (반응소결법으로 제조한 Al기 복합재용 Fe-Al합금 예비성형체의 특성평가)

  • Choi, Dap-Chon;Park, Sung-Hyuk;Joo, Hyung-Gon
    • Journal of Korea Foundry Society
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    • v.19 no.6
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    • pp.493-500
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    • 1999
  • Squeeze casting was used for fabricating a light metal base composite having high strength and wearresistance. Reactive sintering was used to prepare the preform of Squeeze casting. To utilize Fe-Al intermetallic compounds and SiC particle as a reinforcement, there needs to prepare Fe-Al mixed powder at 50, 60, 70at.%Al, and add SiC powder to the above mixture at 4, 7, 16, 24wt.%. The prepared mixture with SiC was reactive sintered in a tube furnace at $660^{\circ}C$ to get a porous hybrid preform of intermetallic compound and SiC. The preform prepared above was placed in a metal mold, preheated at $660^{\circ}C$ AC4C matrix was injected into the mold with the temperature of the melt at $610^{\circ}C$ After these processes, 66MPa was applied to the mold for 5 minute to finish the whole procedure. The maximum reaction temperature was increased with the increased Al amount, but decreased with the increased SiC amount. The density of the preform was decreased with SiC amount increase in the compacts due to swelling of the preform. An optical microscope was applied to observe the micro structure and the dispersion of the reinforcements. To analyze phases, We utilized XRD, EDS. Hardness test were chosen to get the information of mechanical properties. There were no significant changes in micro structure between the composite and preform. However, it was shown that uniform dispersion of the reinforcers and complete infiltration of the melt into the preform were achieved through the procedure of the squeeze casting. It was observed that the hardness of the composite is decreased with increased SiC amount, resulting from the volumetric expansion of the preform.

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Studies on the Improvement in Quality of Rice Candy by adding Red Ginseng Marc. (홍삼박 첨가에 의한 엿의 품질향상에 관한 연구)

  • Lee, B.Y.;Lee, E.K.;Kim, B.G.;Kim, K.C.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.15 no.1
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    • pp.53-61
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    • 2013
  • To improve the quality of rice candy, We studied on manufacturng method and characteristic of rice candy by adding ratio of red ginseng marc. The results obtained were as follows: The boiled rice was added with 15 % malt extract to 1.2 times. After it was saccharified for 12 hours to 70℃, we concentrated it and made black rice candy. Then red ginseng marc was dried at 18% of moisture content and disrupted to 30 mesh below for manufacturing red ginseng marc's powder. Maintained at about 100℃, black rice candy added red ginseng marc's powder. These were mixed evenly and dried. Finally, rice candy adding red ginseng marc was completed. According to the characteristics of rice candy by adding red ginseng marc, the more amounts of red ginseng marc was increased, the less hardness and adhesiveness of rice candy was decreased. Also the brightness of the color difference was decreased. but yellowness and redness was increased. When adding red ginseng marc at 17.5%, it was evaluated to the good score in sensory evaluation.

Development and Research on a Functional Hydrolyzed Whey Protein Powder Product with Sialic Acid as a Marker Compound - II. Repeated 90-day Oral Administration Toxicity Test using Rats Administered Whey Protein Powder containing Highly Concentrated Sialic Acid (23%) produced by Enzyme Separation and Solvent Enrichment Method - (Sialic Acid를 지표성분으로 하는 유청가수분해단백분말의 기능성식품 개발연구 - II. 효소분리 용매정제로 고농도 Sialic Acid가 함유된 유청가수분해단백분말(23%)의 랫드를 이용한 90일 반복경구투여 독성시험 평가 연구 -)

  • Noh, Hye-Ji;Cho, Hyang-Hyun;Kim, Hee-Kyong;Koh, Hong-Bum
    • Journal of Dairy Science and Biotechnology
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    • v.34 no.2
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    • pp.117-135
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    • 2016
  • The present study was performed to develop a functional raw food material from hydrolyzed whey protein powder (23%-GNANA) medication containing sialic acid as a marker compound that is naturally occurring at 7% concentration in GMP (glycomacropeptide). GMP is used worldwide in foodstuffs for babies and infants and is obtained from the milk protein as safe food. While the purpose of our detailed evaluation was aimed to assess preliminary NOAEL values for and above 2,000 mg/kg/day, a clinical dose allowance for 23%-GNANA (as per characteristic of a functional health product, a highly refined test substance of 23% (v/v) sialic acid combined in GMP), at the same time we also wanted to assess the safety of GMP hydrolyzate lacking sialic acid but with identical properties as GMP. Animal safety evaluation was conducted using 23%-GNANA as the test substance, produced from hydrolyzed whey protein powder (product name: HELICOBACTROL-23; provided by Medinutrol Inc. [Korea]; composed of 23% sialic acid and GMP protein) after isolating the sialic acid using enzymes approved as food additives, with GMP as a raw material, and subsequently increasing the content of xx up to 23% through 80% (v/v) ethanol soaking and concentrating, in accordance with GLP Guideline. The animal safety evaluation mentioned above was made on the basis of toxicity in SPF Sprague-Dawley female and male rats dosed with 10 mL of the test substance diluted to 0, 1,250, 2,500, and 5,000 mg/kg directly into their stomachs for 90 d. This was determined in terms of the general symptoms and animal viability, weight and amount of feed intake, eye examination, uracrasia tests, hematological and blood biochemical disorder tests, blood coagulation test, abnormal intestine weight, abnormalities during postmortem and histopathological examinations. Statistical significance was set at P<0.05. Based on the toxicity determination, a certain minor effect associated with the test substance was observed in male rats with no major effects of the tested substance, in comparison with the control group dosed with sterilized water. Nevertheless, the NOAEL value, evaluated as per toxicity criteria, was verified as 5,000 mg/kg/day (P<0.05). Similarly, for female rats, a certain minor effect associated with the test substance was observed in 5,000 mg/kg/day dosed group, with no major effect, yet the NOAEL value (as assessed as per toxicity criteria) was determined to be 5,000 mg/kg/day (P<0.05), which was the same as for male rats. Accordingly, the NOAEL values of the test substances for all female and male rats were finally verified as 5,000 mg/kg/day (P<0.05). In conclusion, it was determined that the 23%-GNANA test substance exceeds 2,000 mg/kg/day, the clinical allowance characteristic for functional health food, and was finally evaluated to cause no safety concerns when used as a raw material in functional health food production, which was the ultimate goal of the present study.

Characteristic Changes of Disposable Clothes Fabric on Printing using Natural Dyeing (천연염재를 활용한 일회용 작업복 소재의 기능성 특성 평가)

  • Shin Jung-Sook
    • The Research Journal of the Costume Culture
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    • v.12 no.6 s.53
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    • pp.1010-1020
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    • 2004
  • The purposes of this study were to investigate characteristic changes on nonwoven fabric by the charcoal and the yellow soil printing. It separate the grind charcoal and the yellow soil as two different size of particles $45{\sim}52{\mu}m\;and\;53{\sim}65{\mu}m$ for hand screen printing on three kind of nonwoven fabrics. To examine the effect of the charcoal and the yellow soil printing on nonwoven fabric were to observe surface changes by a scanning electron microscope, dyeability by using spectrophotometer, moisture regain by oven method, deodorization and antibacterial activity. The results were as follows: When the charcoal and the yellow soil powder concentration increased from 3 to $9\%$ or from 5 to $10\%$, K/S value also increased from 3.06 to 8.55 or from 1.14 to 1.80. The charcoal and the yellow soil moisture regain also increased. In same concentration, moisture regain occurred higher as particle of small size. In concentration of charcoal $3\%$, rate of deodorization measured as $89\%,\;83\%\;and\;87\%,\;and\;9\%$ concentration caused $96\%,\;86\%\;and\;93\%$ of high deodorization. In concentration of 5, $10\%$ of yellow soil, rate of deodorization measured as $85\%$ over. Antibacterial activity examination in nonfinished nonwoven fabric resulted range of $60\%$, however, $3\%\;and\;9\%$ concentration finished nonwoven fabric resulted $99.9\%$ of excellent antibacterial activity. Also $5\%,\;10\%$ yellow soil concentration was appeared same resoult.

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Photoluminescence of Al2O3:xCr2O3 Solid Solution and Application as the Additive for Improving CRI of Red Phosphor (Al2O3:xCr2O3 고용상의 발광특성과 적색형광체의 연색성 향상을 위한 첨가제로의 응용)

  • Chae, Ki-Woong;Cheon, Chae-Il;Kim, Jeong-Seog
    • Journal of the Korean Ceramic Society
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    • v.47 no.2
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    • pp.122-126
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    • 2010
  • In this article photoluminescence of the $Al_2O_3:xCr_2O_3$ solid solutions prepared by solid state reaction method are represented. The effect of $Cr_2O_3$-activator concentration and heat treatment time on the PL characteristics have been discussed in conjunction with microstructure of phosphor samples. The $Al_2O_3:xCr_2O_3$ phosphors show the highest PL intensity at x=0.003 mole when the samples are reacted at $1600^{\circ}C$ for 5 h. The PL emission and absorption spectra show the maximum peaks at 698 nm and at 398 nm respectively. The CIE color coordinate is (x=0.646, y=0.316) at 0.003 mole $Cr_2O_3$, which value is very close to the NTSC coordinate of red color. This characteristic feature of $Al_2O_3:xCr_2O_3$ has been applied for an additive to improve the color characteristic of other red phosphor $LiEuW_2O_8$ which has a relatively poor color purity with an emission peak centered at 615 nm and with a CIE coordinate (x=0.530, y=0.280). The $Al_2O_3:0.003Cr_2O_3$ phosphor has been mixed with the $LiEuW_2O_8$ phosphor powder and the PL characteristics and CIE color coordinates are characterized. The $Al_2O_3:xCr_2O_3$ phosphor was found effective for improving the CRI (color rendering index) of $LiEuW_2O_8$ phosphor.

Infrared Spectra of Wood Powders from Pinus densiflora, Populus alba x glandulosa and Quercus mongolica (소나무, 현사시나무 및 신갈나무의 적외선(赤外線)스팩트럼)

  • Kong, Young-To
    • Journal of Korean Society of Forest Science
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    • v.52 no.1
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    • pp.31-36
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    • 1981
  • The infrared specta of wood powders have been recorded both in the untreated stste and after treatment through 1%-NaOH extraction(2hrs) and alcohol-benzene mixture extraction. Differences between the spectra of 3 species(Pinus densiflora, Populus alba x glandulosa and Quercus mongolica) can be explained chiefly in terms of theirs chemical compositions through comparisions of the spectra of pure cellulose powders. 1. The peak near $3400cm^{-1}$ from wood powders appeared at $3420cm^{-1}$, which was shifted to left compared with pure cellulose powders. 2. Many new peaks appeared at 2725, 1730, 1660, 1640, 1600, 1510, 1500, 1460, 1385, 1270, 830 and $810cm^{-1}$ etc., which were not appeared in pure cellulose powders. 3. Pinus densiflora spectra of untreated powders showed small peak appeared at $2840cm^{-1}$, which was the most characteristic band. There were peaks at $1240cm^{-1}$ in Populus alba x glandulosa and Quercus mongolica spectra of untreated wood powders. 4. Treated wood powder spectra showed weak or no peaks at near $1730cm^{-1}$ and also at near $2920cm^{-1}$. $2840cm^{-1}$, near $1385-1365cm^{-1}$, near $1235cm^{-1}$ and $1110-1095cm^{-1}$ etc. 5. The Alcohol-benzene extractive spectrum from Pinus densiflora showed many peaks at $3600-2300cm^{-1}$, $3100-2800cm^{-1}$, $1700cm^{-1}$, $1450cm^{-1}$ and $1375cm^{-1}$ etc. The most characteristic band of the extractives appeared at $3100-2900cm^{-1}$.

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Study on Mixing Characteristic and Rheology of Polymer/Graphite Composites for a Bipolar Plate of Polymer Electrolyte Membrane Fuel Cell (고분자 전해질막 수소 연료 전지 분리판 용 고분자/흑연 복합 재료의 혼합 및 유변학적 특성에 관한 연구)

  • Yoo, Tae-Hyun;Kim, Dong-Hak;Son, Young-Gon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.10
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    • pp.4673-4678
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    • 2011
  • In this paper, studies on a mixing characteristic and viscosity measurement of polymer/graphite composites for a bipolar plate of the polymer electrolyte membrane fuel cell were presented. Since the materials for the bipolar plate should be electrically conductive, contents of solid graphite in the composite are very high. As a consequence, a viscosity of the polymer/graphite composite used for the bipolar plate is very high and the measurement of the viscosity is difficult. Viscosity measurements of the polymer/graphite composites were not possible because pressure drops were continuously fluctuated during the viscosity measurements when a conventional capillary die was used. After the die design was optimized, the steady state pressure drop could be achieved, but the viscosity thus measured was not reproducible. After many trials with different experimental techniques, it was found that melt blending of the grinded powder mixtures of both PET and graphite provides reproducible viscosity measurements and electric conductivities of the polymer/graphite composites.