• Title/Summary/Keyword: 유리구

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Effect of the Surfactant Concentration on the Formation of Water Glass-based Porous Hollow Silica Microsphere (Porous한 물유리 기반 실리카 중공 미세구 형성에 대한 계면활성제 농도의 영향)

  • Lee, Jihun;Kim, Younghun;Kim, Taehee;Park, Hyung-Ho
    • Journal of the Microelectronics and Packaging Society
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    • v.28 no.4
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    • pp.79-83
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    • 2021
  • In this study, hollow silica microspheres (HSM) of various sizes formed according to the concentration of surfactants using water glass as a precursor, which is advantageous for commercialization due to its lower unit cost compared to conventional silicon alkoxide (tetraethyl orthosilicate, TEOS) was synthesized. The physical properties of the silica hollow microspheres according to the concentration of surfactant were analyzed using Fourier transform infrared, contact angle measurement, Brunauer-Emmett-Teller and Barrett-Joyner-Halenda analyzers and field emission scanning electron microscopy. When porous water glass-based hollow silica spheres were prepared by adding a surfactant at an appropriate concentration, it was confirmed that excellent hollow silica spheres were formed with a specific surface area of 169 m2/g, an average particle size of 25.3 ㎛, and a standard deviation of 6.25.

All-inside Arthroscopic Capsular Imbrication and Lateral Release in Patellofemoral Instability (Operative technique) (슬개대퇴관절 불안정성에서의 관절경적 All-inside 관절막 중첩술 및 외측 지대 유리술 (수술 술기))

  • Kim, Jae-Hwa;Cho, Duck-Yun;Yoon, Hyung-Ku;Kim, Jung-Ryul
    • Journal of the Korean Arthroscopy Society
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    • v.10 no.1
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    • pp.118-122
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    • 2006
  • Purpose: We introduce a technique of all inside arthroscopic capsular imbrication and lateral release used to treat patellofemoral instability. Methods: With the arthroscope in the anteromedial portal for best viewing, the arthroscopic scissor is placed through superolateral portal for proximal to distal release. The release performed 5mm to 1cm from the edge of the patella. After completion of the procedure, with the arthroscope in anterolateral portal, we inserted 5mm cannula in superolateral portal and made working portal from superomedial portal. Medial reefing was performed with all inside technique by using curved needle of the spectrum suturing system and No. 1 monofilament PDS suture is passed through the superomedial portal percutaneously and retrieved through a superolateral portal. Conclusion: Several methods for arthroscopic patella realignment have been proposed, but they have consisted primarily of arthroscopically assisted techniques using a medial incision. We believe that our procedure is preferable to arthroscopically assisted methods commonly used, in that an incision is avoided and the vastus medialis obliqqus is not violated. Our technique is minimally invasive and is easy to control the tightness of the medial patellofemoral ligament (MPFL) under direct vision.

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Free amino acids in traditional Soy sauce prepared from Meju under different Formations (메주의 형상에 따른 재래식 간장의 유리아미노산)

  • Seo, Jeong-Sook;Lee, Taik-Soo
    • Journal of the Korean Society of Food Culture
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    • v.7 no.4
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    • pp.323-328
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    • 1992
  • Three kinds of soy sauce were prepared using the brick type of conventional meju (A), the brick type of meju of Aspergillus oryzae (B), and the grain type of meju of Aspergillus oryzae (C) in summer. Free amino acids were analyzed in according to aging time of those products. Findings are as follows. Lysine, histidine, serine, glycine, valine, methionine, and phenylalanine were detected in all kinds of soy sauce at the beginning preparation. Aspertic acid, glutamic acid, alanine, threonine, arginine, and leucine were detected during 90 days. Isoleucine and tyrosine were detected during 180 days. Lysine and histidine were shown higher content among the detected free amino acids. The each content of glutamic acid, aspartic acid, and methionine was decreased in passing the aging time. The total content of free amino acids was shown 3,559-4,119 mg/100 ml at the 180 days. The total content of free amino acids of soy sauce C was higher than that of other soy sauces.

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A Study on the Properties and Utilization of Chitosan Coating 2. Changes in the Quality of Tomatoes by Chitosan Coating (게껍질에서 추출한 chitosan 필름의 이용에 관한 연구 2. Chitosan 코팅처리한 토마토의 품질변화)

  • KIM Hyonng-Seub;SON Byung-Yil;PARK Seong-Min;LEE Keun-Tai
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.5
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    • pp.568-572
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    • 1999
  • Coating with chitosan ($2\%$, pH: 5.0) had a beneficial effect such as less weight loss, flesh firmness and maintenance of sugar content of tomatoes stored at the normal temperature. The weight loss of chitosan-coated tomatoes was $4.8\%$ during the storage-period (18days) while that of control was $10.2\%$. When it was stored for 18 days, the tomatoes coated with chitosan showed higher in firmness (1.63 kg) and pectin content ($0,58g\%$) than the control (1.03 kg, $0.44g\%$). For the total soluble acid and pH, the tomatoes coated with chitosan were higher in oxalic acid ($0.17 g\%$) than the control ($0.15 g\%$) and the latter were higher in the pH than the former, when they were stored for 18 days.

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Changes of Free Amino Acid Compositions and Sensory Properties in Kochjang Added Sea Tangle Powder during Fermentation (다시마를 첨가한 고추장의 숙성 중 유리아미노산 조정 및 관능적 특성 변화)

  • 배태진;최옥수
    • The Korean Journal of Food And Nutrition
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    • v.14 no.3
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    • pp.245-254
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    • 2001
  • 우리나라의 전통 발효식품인 고추장의 관능성 및 기능성을 더하여 품질을 향상시키기 위하여 전분질원료인 찹쌀무게에 대하여 2%. 4%, 6%, 및 8%의 다시마 분말을 첨가한 후 대조구와 함께 3$0^{\circ}C$에서 12일간 숙성시키면서 유리아미노산과 지방산 조성 acl 관능적 특성을 검토하였다. 숙정 중 대조고추장과 다시마고추장 모두에서 아미노질소는 서서히 증가하는 것으로 나타났으나 아미노질소의 경우 대조고추장에 비해 다시마 고추장에서 다소 낮게 나타났다. 숙성 30일째의 아미노질소량은 각각 171.31mg%, 172.10mg%, 174.18mg%, 185.60mg 및 161.70mg%로 최고값을 보였다 유리아미노산 중에서는 glutamic acid의 함량이 가장 높은 것으로 나타났는데 숙성 이 진행될수록 증가하였다. 또한 arginine, aspartic acid, proline, serine, leucine, lysine 도 비교적 높은 함량을 가졌다. 고추장에서 분리 확인된 지방산은 lauric acid myris-tic acid, palmitic acid stearic acid , oleic acid, linoleic acid 등이었고, 이들 중 oleic acid의 조성비율이 가장 높았고 palmitic acid가 다음으로 높았으며 stearic acid, lauric acid myristic acid의 경우 숙성 후기로 갈수록 산화되어 감소하는 경향을 보였다. 숙성 60일과 120일에 실시한 관능검사의 결과 8% 다시마 첨가구를 제외하고는 대조고추장과 비교하여 다시마 첨가구를 제외하고는 대조고추장과 비교하여 다시마 첨가가 고추장의 관능적 특서엥 영향을 미치지 않았으며 다시마 첨가수준이 높아질수록 높은 값을 나타내어 고추장에 다시마를 6% 정도 첨가하는 것이 적당하였다.

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Residual Stress in Tempered Plate Glasses (판유리의 열처리에 의한 잔류 응력)

  • 공진학;정관수;강태진
    • Proceedings of the Korean Fiber Society Conference
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    • 2002.04a
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    • pp.297-300
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    • 2002
  • 유리는 광학적으로 우수한 재료이나, 역학적 성질이 취약하여 이를 보완하기 위해 열처리 공정을 받게 된다. 열처리 공정에서 유리는 두께 방향으로 분포를 가지는 잔류 응력을 얻게 되고 이로부터 유리는 물성의 향성을 얻을 수 있다. 본 연구의 목적은 잔류 응력을 구하는 기존 방법[1]에 개선된 수치 해석법[2]을 도입하고, 보다 정확한 열변형율의 계산[2]을 통해, 기존의 잔류 응력 값[l]보다 향상된 잔류 응력 값을 구하는데 있다. (중략)

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Study on the Vitrification of Porcine GV and M II Oocytes after Removal of Cytoplasmic Lipid Droplets (세포질 내 지방구 제거가 돼지 난포란의 유리화 동결에 미치는 영향)

  • 최인경;이승진;송해범
    • Journal of Embryo Transfer
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    • v.18 no.1
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    • pp.1-14
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    • 2003
  • This study was conducted to investigate that the immature and mature oocytes of porcine can be cryopreserved by vitrification. Oocytes were centrifuged to polarize the cytoplasmic lipid droplets. The lipids were removed from cytoplasm by micromanipulation. Delipated oocytes were centrifuged after being preincubated with cytochalasin B(CB) fer 10 min, and lipid droplets were removed. Centrifuged oocytes were treated with CB and centrifuged to polorize lipid droplets but not delipated and control oocytes is not-treatment. Oocytes of three types were vitrified in electron microscope(EM) grids. The results of survival, maturation and cleavage rates were as follows. 1 The survival rates of immature oocytes were 15.1%, 0% and 0% in the Delipated, Centrifuged and Control after vitrification, respectively, and its rate of Delipated wassignificantly higher than Centrifuged and Control(P<.01). 2. The survival rates of mature oocytes were 12.21%, 0% and 0% in the Delipated, Centrifuged and Control after vitrification, respectively, and its rate of Delipated was significantly higher than Centrifuged and Control(P<.01). 3 The maturation rates of immature oocytes were 37.5% and 68.9% for metaphase II in the Delipated after vitrification and Non-vitrification, respectively, and its rate of Non-vitrification was significantly higher than Delipated after vitrification(P<.01). 4. The cleavage rates of immature oocytes were 12.5%, 0%, 0% and 56.1% in the Delipated, Centrifuged, Control after vitrification and Non-vitrification, respectively. It's rate of Delipated was higher than Centrifuged and Control, but there were no significant difference, and its rate of Non-vitrification was significantly higher than Delipated, Centrifuged and Control(P<.05). 5 The cleavage rates of mature oocytes were 25.0%, 0%, 0% and 67.9% in the Delipated, Centrifuged, Control after vitrification and Non-vitrification, respectively. It's rate of Delipated was higher than Centrifuged and Control, but there were no significant difference, and its rate of Non-vitrification was significantly higher than Delipated, Centrifuged and Control(P<.05).

Changes of Free Sugars, Lipoxygenase Activity and Effects of Chitosan Treatment during Cultivation of Soybean Sprouts (콩나물 재배중 유리당과 Lipoxygenase Activity의 변화 및 이들에 미치는 키토산 처리의 영향)

  • Lee, You-Seok;Lee, Chong-Ouk
    • Korean Journal of Food Science and Technology
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    • v.31 no.1
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    • pp.115-121
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    • 1999
  • Changes of free sugars, lipoxygenase activity and effects of chitosan treatment were analyzed during cultivation of soybean sprout. Free sugars(sucrose, raffinose and stachyose) were more rapidly decomposed in the cotyledon of soybean sprout. Contents of sucrose and raffinose in control group were decreased more rapidly than those of chitosan treated soybean sprouts (CTSS). But the decreasing rate of stachyose was higher in the CTSS. In the hypocotyl, 82% of L-2/3 activity were decreased, whereas 42% of the activity were decreased in the cotyledon after 132 hours of germination. The effect of chitosan treatment on the lipoxygenase activity was more effective on L-2/3 isozyme than L-1. After the germination period of 132 hours, L-2/3 activity of control group was 82.7unit/mg and that of CTSS was 56unit/mg.

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Study on the Fire Investigation by Damaged Pattern Analysis of Incandescent Lamps (백열전구의 소손 패턴 분석을 통한 화재조사 연구)

  • Kim, Hyang-Kon;Kim, Dong-Woo;Moon, Hyun-Wook;Choi, Chung-Seog;Choi, Hyo-Sang
    • Fire Science and Engineering
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    • v.22 no.5
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    • pp.22-28
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    • 2008
  • In this paper, we conducted experiments on damaged patterns of incandescent lamps by external stress, such as external flame or external impact. Glass bulbs were melted and filaments were evaporated by external flame when the bulbs were lit, and finally molten marks were recognized at the filaments. Also, there were some differences in absorption patterns of evaporated filament elements according to set-up directions, and evaporated filament elements were absorbed in lead-in wires, support, inside of glass. In case the bulbs were lit and they were damaged by external impacts, filament burned out. Filaments were not evaporated but melted. We expect that this results could be used to judge whether electric current flew through incandescent lamps or not in fire site.