• Title/Summary/Keyword: 분쇄물

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Diluted Synthesis of Manocrystalline CeO2 by Mechanical Milling (희석혼합체의 기계적 분쇄에 의한 나노 CeO2의 합성)

  • Lim, Geon-Ja;Kim, Tae-Eun;Lee, Jong-Ho;Lee, Hae-Weon;Rhee, Dong-Joo;Hyun, Sang-Hoon
    • Journal of the Korean Ceramic Society
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    • v.39 no.8
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    • pp.764-768
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    • 2002
  • The nanocrystalline $CeO_2$ was synthesized by mechanical milling and subsequent heat-treatment with the mixture of $Ce(OH)_4$ precursor and diluent, NaCl. Using deionized water, the diluent, NaCl, in the mixture has been easily dissolved out. Diffusion barrier was provided by the diluent during heat-treatment, which suppressed not only the coarsening of primary particle but also the agglormeration between the particles. Crystallite and aggregate size of $CeO_2$ depended on the concentration of diluent, temperature and time of heat-treatment; increased with the temperature and time increases. In case the mixture was heat-treated at high than $600^{\circ}C$, however, the crystallite size was saturated near 20 nm, which was supposed to be due to the densification of diluent.

Metallic Radial Head Prosthesis in Korea (요골두 금속 치환물의 국내 사용)

  • Han, Sang-Hwan;Moon, Jun-Gyu;Park, Jong-Wong;Jang, Ki-Mo
    • Clinics in Shoulder and Elbow
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    • v.10 no.1
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    • pp.84-91
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    • 2007
  • Purpose: The aim of this study was to report seven cases of metallic radial head prosthesis and present the limit of use in Korea. Materials and Methods: Metallic radial head arthroplasty was performed on 7 patients between April 2006 and December 2006, who had complex elbow injury including comminuted radial head fracture. Indication, operative findings and outcome were assessed. Availability and payment of implant were investigated. Results: All of the patients had more than one associated injury including coronoid fracture, olecranoan fracture, and ligament ruptures. According to Mason classification, there were three type III and four type IV fractures. All radial head fractures were too comminuted to reconstruct. There were two excellent results, four good, and one poor, as graded by Mayo score. There were no patient with instability and implant related complications. Insufficient supply of implant did not enable to do scheduled surgery in 2 cases. Current medical insurance did not cover charge for radial prosthesis, five patients could not help paying for that by themselves. Conclusion: Metallic radial head implants are useful when the radial head cannot be repaired reliably. Preoperative preparing and coverage by medical insurance based on appropriate indication are helpful for decision for a treatment option.

Optimization of Enzymatic Hydrolysis for the Production of Antitoxic Bovine Hepatic Extract (항독성 소간추출물의 생산을 위한 효소분해의 최적화)

  • Kim, Hyun-Jung;Kwon, Do-Hyeong;Shon, Dong-Haw
    • Korean Journal of Food Science and Technology
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    • v.40 no.2
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    • pp.190-193
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    • 2008
  • Bovine hepatic extract is recognized as possessing detoxifying activity against various liver diseases. In orderto develop a process for its mass production, various enzymatic hydrolysis conditions were tested, and bovine hepatic extracts were prepared. These extracts were then examined for composition, microorganism levels, and vitamin $B_{12}$ content. Among the enzymes tested, papain was selected based on yields for dry residue and amino nitrogen. The other enzymes tested included bromelain, ficin, pancreatin, and protease NP. The optimal hydrolysis conditions were established at 65$^{\circ}C$ for 24 hr, with an addition of 1%(w/w) papain to the beef liver. The prepared spray-dried bovine hepatic extract showed an 11% recovery yield on a raw beef liver basis, with 95% dry residue and 11.8% total nitrogen content. Microorganisms were not detected in the dried extract, and its vitamin $B_{12}$ content was 4.1 ${\mu}$g/g. In summary, the conditions established in this study could be applied for the high yield mass production of bovine hepatic extract.

IFCI를 이용한 FARO L-14 실험 모의(ISP-39)

  • 황문규;김희동
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.10a
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    • pp.732-737
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    • 1997
  • 본 연구에서는 IFC6.0코드 검증과 개선점 파악을 목적으로 유럽공동체 연구소 JRC-Ispra에서 수행한 Faro L-14실험을 모의하였으며 이는 ISP-39 참여하에 수행하였다. ISP-39는 용융물과 냉각재 반응 시 용융물 냉각 현상에 있어 관련 해석 코드를 검증하고 각 코드의 한계점을 파악하는데 그 목적을 두고 있다. 계산 결과 용기 내 압력상승 및 냉각재 상승에 관한 경향은 잘 모의하고 있다. 한편 절대값에 있어 실험치에 미치지 못하는 것은 냉각재와의 혼합 시 용융물의 분쇄가 실제보다 덜 예측되고 이에 따른 열전달량의 예측 미달로 인한 것으로 보이며 결국 Lagrangian코드개발의 필요성이 확인되었다.

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Inhibition Effect of Phenolic Compounds from Ultra-fine Ground Chrysanthemum indicum L. on Xanthine Oxidase (초미세 분쇄한 감국으로부터 추출된 phenolic 화합물의 xanthine oxidase 저해 효과)

  • Cho, Young-Je;Kim, Byung-Oh;Park, Hye-Jin;Lee, Eun-Ho;Jo, Jae-Bum;Lee, Jae-Eun;Lim, Su-Bin;Kim, Ye-Jin;Park, Ki-Tae;Choi, Moo-Young
    • Journal of Life Science
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    • v.27 no.8
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    • pp.902-908
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    • 2017
  • In this study, the extracted phenolic compounds from 98 species of oriental herbal medicine were examined for biological activities to be used as functional resources. In particular, the anti-gout effect by xanthine oxidase (XOase) inhibition was determined using water and ethanol as extraction solvents because of their non-toxicity in the human body. The extracts of Chrysanthemum indicum L. (83.45%), Cuscuta chinensis (60.22%), Asiasarum sieboldi F. Maekawa (51.66%), Acorus gramineus (67.8%), Aconitum pseudo-laeve var. erectum (75.23%), Thuja orientalis (47.27%), Polygonum aviculare (53.98%), Carthami semen (63.99%), and Syzygium aromaticum (40.22%) showed relatively high XOase inhibitory activity. Chrysanthemum indicum L. was selected for its high XOase inhibitory activity. The biological compounds in Chrysanthemum indicum L. were identified to contain phenolics included in extracts of solids. Ultra-fine grind technology showed a higher extraction yield than normal grind and fine grind technology. Ethanol extracts showed relatively higher XOase inhibitory activity than water extracts. XOase inhibitory activity increased in a dependent manner as phenolic concentration increased. Therefore, ultra-fine grind technology was confirmed for use in increasing the extraction yield of XOase inhibitory compounds from Chrysanthemum indicum L.. Extracts from Chrysanthemum indicum L. are expected to be a useful functional resource for the prevention or treatment of gout.

Effect of Natural Ingredients and Red Wine for Manufacturing Meat Products on Radiation Sensitivity of Pathogens Inoculated into Ground Beef (식육제품 제조용 천연 부재료 및 적색 와인이 분쇄 우육에 접종된 병원성 미생물의 방사선 감수성에 미치는 영향)

  • Yun, Hye-Jeong;Kim, Hyun-Joo;Jung, Yeon-Kook;Jung, Samooel;Lee, Ju-Woon;Jo, Cheo-Run
    • Food Science of Animal Resources
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    • v.30 no.5
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    • pp.819-825
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    • 2010
  • This study was conducted to investigate the effect of various natural ingredients for manufacturing meat products on the $D_{10}$ value and relative radiation sensitivity (RRS) of foodborne pathogens inoculated into ground beef. The pathogens used for this study were Salmonella Typhimurium (KCTC 1925), Escherichia coli (KCTC 41682), Listeria monocytoges (KCTC 3569), and Staphylococcus aureus (KCTC 11764), and the natural ingredients added into ground beef were garlic, onion, black pepper, hot pepper, ginger, green onion, carrot, and red wine. The $D_{10}$ of E. coli was decreased significantly by 5% of garlic addition (RRS=1.460), and the addition of carrot (RRS=1.086) and red wine (RRS=2.864) also showed similar results. Most natural ingredients were effective in increasing radiation sensitivity of L. monocytogens, but only garlic, onion, hot pepper, carrot, and red wine were effective against S. aureus. In particular, the addition of red wine to ground beef showed the greatest increase of radiation sensitivity for 3 pathogens tested in the present study, except for S. Typhimurium. Results indicate that the use of certain natural ingredients for manufacturing processed meat products may have effects in the increase of radiation sensitivity of pathogens. This increased radiation sensitivity can reduce the target irradiation dose for obtaining the same level of safety, resulting in lowering the adverse quality changes caused by a high-dose irradiation process.

Effect of Pre-Treatment of Pig Slurry for Methane Production in Anaerobic Digestion Process (돼지분뇨 슬러리 전처리가 메탄 생성 효율에 미치는 영향)

  • Kwang, Hwa-Jeong;Ryu, Seung-Hyun;Namkung, Kyu-Cheol;Khan, Modabber Ahmed;Han, Duk-Woo;Kwag, Jung-Hoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.21 no.4
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    • pp.62-71
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    • 2013
  • This study was carried out to develope a pre-treatment technology for anaerobic digestion. Breaking down large particles into smaller particles enhances the performance of anaerobic digestion by increasing the hydrolysis of particles. A degree of hydrolysis is the most important factor determining the overall efficiency of methane production. Three types of pre-treatment devices (blade-type crusher, ozonization system, cavitation system) were set up and operated to crush solids in pig slurry in order to enhance biodegradability. The effect of pre-treatment on decreasing granular size within pig slurry by three experimental devices were compared. The highest performance of granulization of pig slurry was attained in a combination of blade-type crusher and ozonization system. In batch experiment, there was an improvement of the methane potential by combined pretreatment with crusher and cavitation. In case of pre-treated slurry, biogas and methane production were 325.9 L and 59.7% respectively, while, in untreated slurry, the production were lower; 298.8 L and 55.7%, respectively. These results indicate that higher anaerobic digestion efficiency of pig slurry can be obtained through the pre-treatment.

Selective Removal of Arsenic Compounds from the Contaminated Paddy Soil in China Using Froth Flotation Technique (포말부선 기술을 이용한 중국 오염농경지내 비소화합물의 선택적 제거)

  • Lee, Seungwoo;Jeon, Chilsung;Lee, Eunseong;Yoo, Kyungmin;Choi, Junhyun;Kim, Hyunjung
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.7
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    • pp.343-352
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    • 2016
  • Effects of grinding time and chemicals dosage in arsenic removal from contaminated paddy soil in China were investigated using lab scale attrition and froth flotation combining process. Arsenic concentration in the field soil was 76.51 mg/kg, exceeding Korean and Chinese standards, and predominant arsenic compounds fraction in sequential extraction was "residual" (over 80%). After wet sieving, soil with >2 mm and < 0.038 mm showed concentration lower than 'Warning Level' in Korea. Soil with 0.038-0.075 mm, showing the highest concentration, was discarded since it occupied minor weight fraction (10.1%). Thus soil between 0.075 and 2 mm was only used in the combining process. The highest Arsenic concentration in progeny fragments smaller than 0.038 mm reached up to 981.66 mg/kg after 5 min of attrition. Optimal dosage of collector ($C_5H_{11}OCS_2K$) and modifier ($Na_2S$ and $CuSO_4$) in froth flotation process for the selective separation of the chipped progeny particles from the parent fragments were determined both as 200 g/ton. Arsenic removal efficiency in froth flotation process was 38.47% and it was increased to 72.74% in additional flotation process, scavenging. Average arsenic concentration after overall process - wet sieving, attrition and froth flotation - was estimated to 16.45 mg/kg.

Extraction Yield and Anti-Yeast Activity of Extract from Green Tea Seeds by Pretreatment and Extraction Conditions (녹차씨 전처리와 추출 조건에 따른 녹차씨 추출물의 추출 수율 및 항효모 활성)

  • Yang, Eun Ju;Seon, Yoo Kyung;Wee, Ji-Hyang
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.9
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    • pp.1351-1357
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    • 2016
  • Green tea (Camellia sinensis) seed extract (GTSE) was prepared under various pretreatment conditions and used to investigate its extraction yield and anti-yeast activity. Anti-yeast activity of GTSE from seeds with or without the coats was the same, whereas the extraction yield was slightly higher in extract from seeds without the coat. Anti-yeast activity of GTSE from seeds with different water contents or particle sizes was the same, whereas the extraction yield was highest in extract from seeds with 7.3% moisture or a smaller particle size. Anti-yeast activity of defatted green tea seed extract (DGTSE) was the same as that of GTSE. Extraction yield was higher in DGTSE from defatted seeds by the oil press machine compared to hexane extraction. Defatted green tea seed (DGTS), a by-product from the oil extraction process, is a good natural source of anti-yeast preservative. The extraction yield and anti-yeast activity of DGTSE were investigated using various extraction solvents, temperatures, and times. The results show that water was an economic extraction solvent, and anti-yeast activity of DGTSE was unstable at $90^{\circ}C$. These results suggest that water, extraction temperature of $50^{\circ}C$, and extraction time of 4 h were the most efficient for extraction of anti-yeast compounds from DGTS.