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A Study on the Pretreatment of BaTiOx Ceramics for the Analysis of Ba, Ti and W using Acid Digestion Bomb (가압 산분해법을 이용한 BaTiOx계 세라믹재료 중 Ba, Ti 및 W 분석을 위한 전처리 연구)

  • Park, Kyung-Su;Kim, Sun-Tae;Shim, Eui-Sup;Seo, Min-Jung;Lee, Seoung-Jae
    • Analytical Science and Technology
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    • v.15 no.1
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    • pp.15-19
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    • 2002
  • The pretreatment of tungsten added $BaTiO_x$ ceramics was performed to improve the recovery of Ba, Ti and W. $BaTiO_x$ ceramics were digested with HF : HCl ( 1 : 2 ) mixture in an acid digestion bomb at $220^{\circ}C$ for 3 hrs. The concentration of Ba, Ti and W were determined by ICP-AES. Recoveries of Ba, Ti and W were 99.6%, 99.8% and 99.2%, respectively. And their C.V. values were 1.02%, 0.73% and 1.79%. Using this method, the analytical results of Ba, Ti and W for a real sample were obainted to be 25.9% (w/w), 38.8% (w/w) and 3.31% (w/w), respectively.

Preparation and Evaluation of Cosmetic Tissue using W/Si/W Multiple Emulsion (실리콘 다중유제 (W/Si/W)를 이용한 화장용 티슈의 개발 및 평가)

  • Han, Sang-Chul;Park, Duck-Sang;Shin, Jae-Hong;Kim, Tae-Hyeon;Park, Jeong-Sook;Cho, Cheong-Weon;Hwang, Sung-Joo
    • Journal of Pharmaceutical Investigation
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    • v.37 no.4
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    • pp.217-222
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    • 2007
  • To develop cleansing tissue composed of silicone multiple emulsions which could easily remove make-up residues and confer skin protecting effect without damaging skin, we formulated various silicone multiple emulsions and evaluated the physicochemical properties including viscosity, cleansing effect, and safety effect. Also, cleansing tissue incorporated with silicone multiple (W/Si/W) emulsion was stored for 6 months, and judged its stability through microscopes under accelerated and long-term condition. Cleansing effect was evaluated by chromameter. Skin hydration effect was determined by corneometer and incorporation effect into non-woven fabric cotton was evaluated by volunteer survey. Low viscosity ranged from 400 centipoise (cP) to 1,000 cP was obtained from a stabilized W/Si/W emulsion containing more than 10% volatile silicone. Mean diameter of fresh W/Si/W emulsion was $20{\mu}m$, but after storage for 3 months at $45^{\circ}C$, the particle size of the W/Si/W emulsion increased up to $50{\mu}m$. Both W/Si/W emulsion-incorporated cleansing tissue and commercial product showed equally good cleansing effect. In addition, skin allergies such as erythema, edema, scaling itching, stinging, burning, tightness and prickling were not observed through macroscopic examination. From the transepidermal water loss results, the cleansing tissue consisting of W/Si/W emulsion showed superior hydration effect to commercial product. In conclusion, this study suggests cleansing tissue using W/Si/W emulsion could be used for an excellent efficacy compared with commercialized cleansing tissue.

Effect of Direct Emulsification Method and Invert Emulsification Method On Droplet Size of O/W Emulsion (O/W 에멀젼 입자의 크기에 미치는 Direct 유화법과 Invert유화법의 효과)

  • 김철훈;박재길
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.20 no.1
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    • pp.64-81
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    • 1994
  • O/W emulsions with mixed nonionic surfactants(polyoxyethylene(20)sorbitan monostearate/sorbitan sesquioleate), liquid paraffin, water prepared by direct inversion emulisification method and continuous inversion emulsification Method. The one-step, two-step and three-step phase inversion emulsification method were used in experiments. Effect of added water on droplet size of final O/W emulsions which is prepared by phase inversion emulsification method were investigated. In direct inversion emulsification method(two-step emulsification method), fine and homogeneous droplets of OIW emulsions were formed after phase inversion steps i.e. ,W/O - (W/O) If double emulsion - O/W emulsion. In continuous inversion emulsification method(three-step emulsification method), fine and homogeneous O/W emulsion were formed after phase inversion steps i.e., W/O - pseudomicroemulsion - O/W. By latter method, more Fine and homogenuous droplets were formed than former method. 10-10, 8 HLB region of mixed non-ionic surfactants could produce most fine droplets. This HLB region had maximum values of solubilization water and This HLB value of mixed nonionic surfactants produced fine and homogenuous droplets.

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Pigment and Monacolin K Content of Beni-koji Fermented with Soybean Curd Residue (비지홍국의 색소 및 Monacolin K 함량)

  • 윤은경;김영희;김순동
    • Food Science and Preservation
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    • v.10 no.3
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    • pp.360-364
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    • 2003
  • This study was conducted to investigate the preparation possibility of Beni-koji by Monascus pilosus using dried soybean curd residue(Biji). The additional effect of water(0-50%), glucose(0-10%, w/w), monosodium glutamate(0-0.l%, w/w) and citrus peel water extracts (0-0.5%, v/w) on the pigment and monacolin K content of the Biji Beni-koji were examined. Optimal added amounts of water was 20% of dried Biji. The highest pigment content(OD at 500 nm) of Biji Beni-koji was 1.06 in 10% glucose, 2.26 in 0.01% monosodium glutamate and 2.61 in 0.4% citrus peel water extracts. The content of monacolin K in the Biji Beni-koji added with 10% glucose, 0.01% monosodium glutamate and 0.4% citrus peel water extracts showed 96.38 mg%(w/w), 118.25 mg%(w/w) and 104.50 mg%(w/w), respectively.

An improvement for the employment rate of the S/W and H/W majors (소프트웨어와 하드웨어 전공자들의 취업률 제고 방안)

  • Lee, Seung-Woo
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.3
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    • pp.525-534
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    • 2012
  • The purpose of this study is to increase the employment rate of graduates in the fields of the S/W and H/W. In order to seek employment in various major fields of the S/W and H/W, firstly, this paper proposes the educational case study that increases the concern about employment and develops learner's ability in the unfavorable major fields. Secondly, this paper presents the future driving improvement for the employment rate on the basis of the department's special characteristics and the actual circumstances in the fields of the S/W and H/W. This paper conducts the surveys of each 40 seniors majoring in S/W and H/W respectively in order to measure the understanding of probability/statistics which has been used as tools in the unfavorable major fields. With the purpose of increasement on the employment rate, the paper is designed to have 3 steps, that is, a preliminary questionnaire for employment preference, major courses connecting probability/statistics and a post-questionnaire for employment preference, which eventually investigates the changes of the perception on employment. This paper is verified by the multiple regression analysis to approve the effect on improving learner's academic achievement.

On the Properties and Synthesis of Nanostructured W-Cu alloys by Mechanical Alloying(II) Sintering Behavior of MA NS W-Cu Composite Powders (기계적 합금화 방법으로 제조된 nanostructured W-Cu 합금의 제조 및 물성 연구(II) -MA NS W-Cu 복합분말의 소결거동-)

  • 김진천
    • Journal of Powder Materials
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    • v.5 no.2
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    • pp.89-97
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    • 1998
  • Sintering behavior of nanostructured(NS) W-Cu powders prepared by mechanical alloying (MA) was investigated as a function of sintering temperature. MA NS W-2owt%Cu and W-3owt%Cu composite powders with the crystal size of 20-30 nm were annealed at 90$0^{\circ}C$, and thermal characteristics of those powders were investigated by DSC. Sintering behavior of MA NS W-Cu composite powders was investigated during the solid-state sintering and the Cu-liquid phase sintering. The new nanosintering phenonenon of MA W-Cu powders at solid-state sintering temperature was suggested to explain the W-grain growth in the inside of MA powders. The sintering densification of MA NS W-Cu powders was enhanced at Cu melting temperature by arrangement of MA powders, i.e., the first rearrangement of MA powders was occurred, and then the rearrangement of W-grains in the sintered parts was also took place during liquid-phase sintering, i.e., the second rearrangement was happened. Due to the double rearrangement process of MA NS W-Cu powders, the high sintered density with more than 96%o was obtained and the fine and high homogeneous state of W and Cu phases was achieved by sintering at 1200 $^{\circ}C$.

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Manufacturing yield challenges for wafer-to-wafer integration (Wafer-to-Wafer Integration을 위한 생산수율 챌린지에 대한 연구)

  • Kim, Sarah Eunkyung
    • Journal of the Microelectronics and Packaging Society
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    • v.20 no.1
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    • pp.1-5
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    • 2013
  • Wafer-to-Wafer (W2W) integration technology is an emerging technology promising many benefits, such as reduced size, improved performance, reduced power, lower cost, and divergent integration. As the maturity of W2W technology progresses, new applications will become more viable. However, at present the cost for W2W integration is still very high and both manufacturing yield and reliability issues have not been resolved yet for high volume manufacturing (HVM). Especially for WTW integration resolving compound yield issue can be a key factor for HVM. To have the full benefits of WTW integration technology more than simple wafer stacking technologies are necessary. In this paper, the manufacturing yield for W2W integration is described and the challenges of WTW integration will be discussed.

OH MASERS TOWARDS THE W49A STAR-FORMING REGION WITH MERLIN AND e-MERLN OBSERVATIONS

  • ASANOK, KITIYANEE;ETOKA, SANDRA;GRAY, MALCOLM D.;RICHARDS, ANITA M.S.;KRAMER, BUSABA H.;GASIPRONG, NIPON
    • Publications of The Korean Astronomical Society
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    • v.30 no.2
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    • pp.125-127
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    • 2015
  • We present preliminary results from OH ground state phase referenced observations carried out with the Multi Element Radio Linked Interferometer Network (MERLIN) and e-MERLIN towards the massive star forming region W49A. There are three active SFRs within this complex: W49 North (W49 N), W49 South (W49 S) and W49 South West (W49 SW). The first epoch of observations was obtained in 2005 with MERLIN while the second epoch was obtained in 2013 with the e-MERLIN upgraded system. In this paper, we present 1665 and 1720 MHz maser emission towards W49 S and W49 SW. Overall, both epochs show good agreement with the previous observations of Argon et al. (2000) carried out with the Very Large Array (VLA). The better sensitivity and wider velocity coverage of the MERLIN/e-MERLIN observations allowed us to discover a new 1720 MHz OH maser site in W49 S.

Reutilization of Enokitake Cultural Waste as Lentinus edodes Cultivation Substrate

  • Chai, Jung-Ki;Lee, Sung-Jin;Kim, Young-Ju;Wi, Kye-Moon
    • Plant Resources
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    • v.3 no.3
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    • pp.226-232
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    • 2000
  • The availability of enokitake cultural waste for Lentinus edodes cultivation was investigated, although hardwood sawdust has traditionally been used as a substrate for this fungus. Firstly, physiochemical characteristics of cultural waste were analysed. Secondly, mycelial growth characteristics and fruiting yields of L. edodes on waste treated in some methods were determined. Physiochemical characteristics of enokitake cultural waste showed that the millwaste complex was a little degraded by enokitake fungus and suggested the probability that most component lost by enokitake could be rice bran. Mycelia of L. edodes grew and fruited well on waste supplemented by fresh rice bran and Quercus sawdust although didn't on waste only. Mycelial growths of these fungi on waste were accelerated when supplemented by rice bran to the percent of 40(w/w) but decreased or suppressed at above ratios(30, 40%, w/w). Supplementations of oak sawdust at above 40%(w/w) of the waste and rice bran at 20%(w/w) of the sawdust allowed such a good mycelial growth as to be selected as a pertinent mixing ratio for fruiting medium. A fruiting yield on enokitake cultural waste supplemented by oak sawdust (at 40% of the waste, w/w) and rice bran (at 20% of the sawdust, w/w) was not inferior to that on oak sawdust supplemented by rice bran only (at 20% of the sawdust, w/w). These results indicated strongly the potentiality of enokitake cultural waste as raw materials for shiitake cultivating substrates.

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Application of White Light Emitting Diodes to Produce Uniform Scions and Rootstocks for Grafted Fruit Vegetable Transplants (과채류 접목 시 균일한 접수와 대목 생산을 위한 백색 LED의 적용)

  • Hwang, Hyunseung;Chun, Changhoo
    • Journal of Bio-Environment Control
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    • v.31 no.1
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    • pp.14-21
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    • 2022
  • Uniform scions and rootstocks should be produced to ensure grafting success. Light quality is an important environmental factor that regulates seedling growth. The effects of warm- and cool-white light emitting diode (LED) ratios on seedling growth were investigated. Scions and rootstocks of cucumber, tomato, and watermelon were grown in a closed transplant production system using LED as the sole lighting source. The LED treatments were W1C0 (only warm-white), W1C1 (warm-white: cool-white = 1:1), W3C1 (warm-white: cool-white = 3:1), and W5C2 (warm-white: cool-white = 5:2). The seedlings grown in W1C1 had the shortest hypocotyls, and the seedlings grown in W1C0 had the longest hypocotyls among the three tested vegetables. The hypocotyls of watermelon scions, watermelon rootstocks, and tomato rootstocks were shortest in W1C1, followed by those in W3C1, W5C2, and W1C0, but there was no significant difference between W3C1 and W5C2, which remained the same as the ratio of cool-white LEDs increased. In addition, tomato scions had the first and second longest hypocotyls in W1C0 and W3C1, respectively, and the shortest hypocotyls in W5C2 and W1C1, along with W5C2 and W1C1, although the difference was not significant. The stem diameter was highest in W1C0 except for tomato seedlings and rootstocks of watermelon. The shoot fresh weight of scions and rootstocks of cucumber and watermelon and the root fresh weight of cucumber scions were lowest in W1C1. These results indicated that different ratios of LED lighting sources had a strong effect on the hypocotyl elongation of seedlings.