• 제목/요약/키워드: polishing degree

검색결과 66건 처리시간 0.027초

티타늄 합금 안경테홈선 제조에 관한 연구 (Study on The Manufacturing of The Titanium-Alloyed Eyerim)

  • 김상연
    • 한국산학기술학회논문지
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    • 제12권3호
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    • pp.1058-1062
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    • 2011
  • 티타늄합금 안경테 홈선을 제작하기 위한 냉간 압연 롤러를 설계하고 제작 후 그에 대한 성능 평가를 실시하였다. 롤러의 표면 거칠기 값은 $Ra=0.05-0.15{\mu}m$이고 $Rz=0.23-0.67{\mu}m$였다. 이 값은 티타늄안경테 PVD(Physical Vapor Deposition)도금을 위한 바렐 연마 후 측정한 표면 거칠기 값 $Ra=0.04{\mu}m$, $Rz=0.3{\mu}m$과 비교할 때 만족할만한 결과였다. Ti-3Al-2.5V(Half titanium)와이어를 냉간 압연한 결과 경도가 221Hv, 247Hv(1st), 270Hv(2nd)등으로 증가하므로 적절한 열처리와 다단압연공정이 필요함을 알 수 있었다.

측면 연마된 열확산 코어 광섬유와 외부 물질의 분산 특성 차이를 이용한 단파장 통과 필터 (A Short Wavelength Filter Based on Dissimilar Dispersive Property Between a Thermally Expanded Cored Fiber and an External Medium)

  • 김광택;이규효;신은수;황보승;손경락;김정근;이동호;송재원
    • 한국광학회지
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    • 제16권6호
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    • pp.494-499
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    • 2005
  • 코어가 확산된 단일모드 광섬유와 외부 물질 사이의 분산 특성의 차이를 이용하여 차단 특성이 우수한 단파장 통과 필터(short-pass filter)를 구현하였다. 두 물질의 결합 방법으로 측면 연마 기법을 도입하였다. 실험 결과 소자의 대역경계 파장(band edge wavelength)은 코어의 확산 정도로 조절이 가능하였다. 일반 통신용 단일 모드 대신에 열확산 코어 확산 광섬유를 도입함으로써 더 예리한 파장응답을 얻을 수 있었다. 열광학 효과를 이용하여 경계 파장을 400nm 이상 가변 할 수 있음을 관측하였다.

양극 산화에 의해 티타늄 표면에 형성된 산화 피막이 세포 부착 및 성장에 미치는 영향 (Influence of Anodic Oxidation Film Formed on Titanium onto Cell Attachment and Proliferation)

  • 노세라;이용렬;송호준;박영준
    • 한국재료학회지
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    • 제16권10호
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    • pp.606-613
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    • 2006
  • This study was purposed to evaluate the influence of anodically oxidized film on titanium (Ti) onto MG-63 osteoblast-like cell attachment and activity. Only scratch lines created by polishing were seen in ASR and ANO-1 groups. About $1.5{\mu}m$-thick homogeneous oxide film which has pores of about $0.5{\mu}m$ diameter were formed in ANO-12. The crystalline structure of the oxide films formed by anodization in phosphoric acid electrolyte was $TiP_2O_7$. The total protein amounts of ANO-1 and ANO-12 groups showed higher values of maximum protein amount than that of AS-R group. At 3 days of incubation, total protein amount showed higher value in ANO-2 when comparing to that of AS-R (p<0.05). Based on the results of ALPase activity test, the degree of MG-63 cell differentiation for initial mineralization matrix formation was similar. For all the test groups after 1 day of incubation, MG-63 cells grew healthily in mono-layer with dendritic extensions. After incubation for 3 days, the specimen surfaces were covered more densely by cells, and numerous micro filaments were extruding to the extracellular matrix.

The Change of Arabinoxylan, Phytic Acid and Vitamin E Contents Whole Wheat Flour depends on the Millig Rate Milling Rate in the Korean Wheat Cultivar 'Saekuemkang'

  • Go Eun Lee;Kyeong-Hoon Kim;Jinhee Park;Kyeong-Min Kim;Chang-Hyun Choi;Mina Kim ;Myoung Hui Lee;Chon-Sik Kang;Jiyoung Shon;Jong-Min Ko
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2022년도 추계학술대회
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    • pp.299-299
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    • 2022
  • Whole wheat is rich in dietary fiber and contains various biological activity substances such as arabinoxylan, phytic acid and phenolic compounds. However, excessive fiber contents of whole wheat has a negative effect on dough formation, making it difficult to process. In this study, we tried to improve the usability of whole wheat by suggesting an appropriate degree of purification of whole wheat from 'Saekeumkang', a domestic wheat cultivar containing protein and gluten suitable for noodle production. The contents of arabinoxylan, phytic acid, and vitamin E were measured in the polishing rate range of 5-20% of whole wheat flour. As the milling ratio increased, the flour properties improved. The arabinoxylan and phytic acid content of whole wheat were 67.95 mg/g and 0.87 mg/g, but when milled at 20%, arabinoxylan and phytic acid were 60% and 80% of whole wheat, respectively. And as the milling ratio increased, the vitamin E content tended to decrease (whole wheat: 4.063 mg/100 g, 20% milled: 2.96 mg/100 g), However, the vitamin E composition ratio did not change. On the other hand, α-tocopherol showed the greatest than other vitamin E isomers. Therefore, further studies needed to optimize milling rate to improve the final product while maintaining the approximate nutritional and functional value of the whole wheat.

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부산지역(釜山地域) 개업치과(開業齒科)의 치과보철물(齒科補綴物)에 관(關)한 만족도(滿足度) 조사(調査)(I) - 일부정식 치과 보철물에 관하여 - (A Study on Satisfaction of Practicing Dentists about Prosthesis in Pusan Part I : About Fixed Prosthetic appliances)

  • 이명곤
    • 대한치과기공학회지
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    • 제10권1호
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    • pp.159-169
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    • 1988
  • Fixed prosthetic appliance is the restorations of damaged teeth with cast metal or porcelain, and of replacing missing teeth with fixed, or cemented prosthesis. Successfully treating a patient by means of fixed prosthodontics requires the thoughtful combination of dentist and dental laboratory technician. In order to know the satisfaction of dentisits about fixed prosthetic appliances-porcelain, precious and non precious metal-, this study was conducted for 69 practicing dentisis in Pusan during Fed. to Mar. 1988 using a questionnaire method and was analyzed by the use of percentage, $X^2$-test The results are obtained as follow: 1. General characteristics of the respondents, The rate of age distribution of practcing dentists responded was as follow : 31$\sim$35 age group is 29.0%, 51$\sim$55age group 18.8%, 41$\sim$45 age group and 46$\sim$50 group each 11.6%, 36$\sim$40 age group and 56$\sim$60 age group 8.7%, over 60 age group 7.3%, below 30 age group 4.3% respectively. The tate of term of practice experience distribution of dentists responded was as follow : 6$\sim$10 year group 26.1%, 25$\sim$25year group 18.8%, 11$\sim$15 years group and 16~20 years group each 13.0%, below 5 years group and over 30 years group each 10.2%, 26$\sim$30 years group 8.7% in order. The rate of respondents’ degree was follow : bachelor group 81.2%, doctor group 13.0%, master group 5.8% in order. The rate of respondents’completed medical specialist course was as follow : non-complete group 75.4%, complete group 24.6%. The rate of having own laboratory in respondents’clinic was as follow : no having own laboratory group 58.0%, having own labiratory group 42.0% The rate of being lab. technician in respondent;s clinic was as follow: non-being lab. technician group 91.3%, being lab. technician group 8.7%. The rate of transactional commercial dental lab. numbers was as follow : I dental lab. group 40.6%, 2 dental lab. group 30.4%, 3 dental lab. group 20.3%, production at own lab. group 8.7% 2. Cognitions about the respondent's job, About cognition of patient numvers, there were neither many nor few group 62.3%, few group 17.4%, many group 15.9%, too many group 4.4% in order.(P<.01) As compared with the ratio of dentists to patient prothetic treatment, there were moderate level group 46.4%, high level group 33.6%, low level group 18.8% in order.(P<.01) By job satisfaction of respondents, the highest percentage group was satisfied group 44.9%, neither astisfied nor disstified group 33.3%, dissatisfied group 14.5%, much satisfied group 7.3%(P<.01). As compared with the level of prosthetics price, the were moderate level group 71.0%, low level group 23.2%, high level group 5.8%(P<.01) 3. Satisfaction and assessment of dissatisfied factor of the fixed prosthetic appliance, As compared with the satisfaction of al prosthetic appliance, there were neither satisfied nor dissatisfied group 59.4%, satisfied group 20.3% dissatisfied group 18.8%, much satisfied group 1.5% in order.(P<.01). About precious and non precious metal crown and bridge, there were neither satisfied nor dissatisfied group 60.9%, satisfied group 24.6%, dissatisfied group 11.6%, much satisfied group 2.9% in order.(P<.01) The reat of respondent;s satisfaction about porcelain crown and bridge was as follow : neither satisfied nor dissatisfied group 43.5%, dissatisfied group 33.3%, satisfied group 21.7%, much satisfied group 1.5%(P<.01). The rate of respondent's dissatisfied factor item of precious and non precious metal crown and bridge was as follow : inadequate margin fit item 39.1% respondent, inadequate occlusion item 24.6%, inadequate adaptation item 23.2%, poor anat omic form item 15.9%, inadequate contact item 31.9%, improper polishing item 4.4%, the rest item 11.6% respectively. The rate of respondent's dissatisfied factor item of porcelain crown and bridge was as follow : inadequate margin fit item 52.2%, inadequate occlusion item 2.9%, inadequate adaptation item 10.1%, poor anatomic form item 11.6%, improper polishing item 1.5%, shade mismatching item 71%, the rest item 7.2% respectively. The rate of cognition of respondents’ about cause of dissatisfied factor on fixed prosthetic appliance by item was as follow : deficiency of sincerity item 55.1%, deficiency of knowledge about work item 47.8%, deficiency of experience item 15.9%, poor quality of using material item 5.8%, the rest item 2.9% respectively.

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도정정도에 따른 식미치 관련 QTL 분석 (QTL Analysis Related to the Palatability Score According to Rice-polishing)

  • 박영희;김경민
    • 생명과학회지
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    • 제28권3호
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    • pp.314-319
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    • 2018
  • 본 실험은 청청과 낙동 조합을 약배양하여 육성한 120 계통을 이용하여 식미치 관련 알칼리붕괴도에 대한 QTLs를 분석하고 탐색된 QTLs 유전자에 위치한 DNA 마카를 선발하여 기존 품종에 적용하여 다음과 같은 결과를 얻었다. CNDH 계통을 이용하여 알칼리붕괴도 변이를 조사한 결과 통일형 품종인 청청과 자포니카형 품종인 낙동 현미는 각각 1.9, 1.6를 보였으며 CNDH 계통은 $3.79{\pm}2.01$를 보였으며 변이 분포는 7.0-1.0까지 분포하였다. 모부본인 청청과 낙동 백미는 각각 5.6, 4.1를 보였으며 CNDH 집단의 평균은 $4.86{\pm}1.55$ 보였으며, 변이 분포는 7.0-2.0까지 분포하였다. 변이 분포 곡선은 비정규분포에 가까운 연속변이를 나타내었다. QTLs 분석에서 현미 1,2 반복에서 qBRA2, qBRA6, qBRA11, 백미 1반복에서 qHRA2-1, qHRA2-2, qHRA2-3, qHRA3, qHRA8, 2반복에서 qHRA2-1, qHRA2-2, qHRA2-3, qHRA3, 4반복에서 qHRA5으로, 이들은 각각 2번, 3번, 6번, 8번, 11번 염색체상에 탐색되었다. 현미, 백미 각 염색체상의 qBRA2, qBRA6, qBRA11의 표현형 변이는 1-9% 분포되었다. 알칼리붕괴도 관련 QTLs 분석 결과에서 탐색된 9개 marker를 토대로 모부본인 청청, 낙동을 기준으로 자포니카형 12품종, 인디카형 6품종에 다형성을 분석하였다. 밴드양상으로 크기에 차이를 보이는 분리비에 적합한 11번 염색체 RM27258을 선발하였다. 이상의 연구결과는 앞으로 미질이 좋은 벼 품종 개발하는데 기초자료로 이용 될 것 이다.

질산화균 활성화조를 이용한 하수처리 공정에서의 유기물 및 질소, 인 제거에 관한 연구 (A Study on Removal of Organism and Nitrogen, Phosphorus in Wastewater Treatment Process Using Nitrifier Activated Reactor)

  • 동영탁;서동환;배유진;박주석
    • 상하수도학회지
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    • 제21권6호
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    • pp.727-735
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    • 2007
  • The use of water by cities is increasing owing to industrialization, the concentration of population, and the enhancement of the standard of living. Accordingly, the amount of waste water is also increasing, and the degree of pollution of the water system is rising. In order to solve this problem, it is necessary to remove organisms and suspended particles as well as the products of eutrophication such as nitrates and phosphates. This study developed a high-end treatment engineering solution with maximum efficiency and lower costs by researching and developing a advanced treatment engineering solution with the use of Biosorption. As a result, the study conducted a test with a $50m^3/day$ Pilot Scale Plant by developing treatment engineering so that only the secondary treatment satisfies the standard of water quality and which provided optimal treatment efficiency along with convenient maintenance and management. The removal of organisms, which has to be pursued first for realizing nitrification during the test period, was made in such a way that there would be no oxidation by microorganisms in the reactor while preparing oxygen as an inhibitor for the growth of microorganism in the course of moving toward the primary settling pond. The study introduced microorganisms in the endogeneous respiration stage to perform adhesion, absorption, and filtering by bringing them into contact with the inflowing water with the use of a sludge returning from the secondary settling pond. Also a test was conducted to determine how effective the microorganisms are as an inner source of carbon. The HRT(Hydraulic Retention Time) in the nitrification tank (aerobic tank) could be reduced to two hours or below, and the stable treatment efficiency of the process using the organisms absorbed in the NAR reactor as a source of carbon could be proven. Also, given that the anaerobic condition of the pre-treatment tank becomes basic in the area of phosphate discharge, it was found that there was excellent efficiency for the removal of phosphate when the pre-treatment tank induced the discharge of phosphate and the polishing reactor induced the uptake of phosphate. The removal efficiency was shown to be about 94.4% for $BOD_5$. 90.7% for $COD_{Cr}$ 84.3% for $COD_{Mn}$, 96.0% for SS, 77.3% for TN, and 96.0% for TP.

공용매가 첨가된 초임계유체 추출공정에서 기능성 지방산의 추출 (Isolation of Functional Fatty Acid in Cosolvent Induced SFE Process)

  • 이승범;박경애;홍인권
    • 공업화학
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    • 제10권3호
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    • pp.438-444
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    • 1999
  • 국내에서 생산되는 현미겨는 약 8.4~14.7 wt %의 지질을 포함하고 있으나 지방산의 양이나 조성은 현미겨의 형태, 토질 상태, 도정과 같은 전처리나 정미도에 영향을 받는다. 현미겨에 포함되어 있는 지질은 보통 palmitic acid, linolenic acid, linoleic acid, oleic acid, stearic acid, tocopherol, squalene 등과 같은 지방산으로 나눌 수 있다. 본 연구에서는 초임계유체를 이용하여 현미겨에서 squalene을 함유한 지방산을 추출하였으며, 각각의 공정에 ethanol을 첨가하여 초임계유체 추출을 시행하였다. 추출물은 GC-MSD로 분석을 하였고, 추출된 현미유의 양은 공정 온도, 압력에 따라 달랐으며, 조성은 초임계 이산화탄소의 환산밀도 (${\rho}_{\gamma}$ reduced density)에 영향을 받았다. 4시간의 공정시간에 약 70~80%의 현미유가 추출되었으며, ethanol을 첨가한 초임계유체 추출은 일반 초임계유체 추출에 비해 추출시간이 단축되며 동시에 추출량이 증가됨을 알 수 있었다. 또한 용매추출 공정에서 검출되지 않았던 squalene이 초임계유체 추출과 ethanol올 첨가한 초임계유체 추출에서 추출됨이 확인되었다.

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유치 상아질 산부식 후 습윤 정도에 따른 조직상 (A STUDY ON THE MICROSCOPIC IMAGES OF DENTIN SURFACES IN PRIMARY TEETH ACCORDING TO SURFACE WETNESS AFTER ACID ETCHING)

  • 오영준;정태성;김신
    • 대한소아치과학회지
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    • 제30권4호
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    • pp.545-553
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    • 2003
  • 상아질 접착력을 높이기 위해서는 적절히 습윤한 상아질 표면을 얻는 것이 중요하다. 이런 방법에는 정확한 지침이 없으며, 주관적이고 술자에 따라 많은 차이가 있다. 본 연구에서는 적절히 습윤한 상아질을 얻는 방법에 관한 연구의 일환으로, 유치의 산부식 후. 여러 가지 방법을 이용해 상아질을 건조시킨 표본의 조직상을 획득하여 상아질 표면의 차이를 비교하고자 하여 다음과 같은 결론을 얻었다. 1. 유치 상아질을 산부식하면, 도말층이 제거되고 상아세관이 노출되며, 관간상아질과 관주상아질이 탈회되고, 교원섬유가 풍부한 이행층이 노출되는 것을 확인할 수 있었다. 2. 산부식된 상아질이 과도하게 건조되면 탈회된 상아질이 수축하여, 관간상아질이 붕괴되어 높이가 점차적으로 낮아지고 상아세관의 직경은 조금씩 감소되는 것으로 나타났다. 3. 유치 산부식 후, 10cm 거리에서 20초 동안 압축 공기로 건조시키면 상아질이 과도하게 건조, 탈수됨을 확인할 수 있었다. 4. 유치 산부식 후, 10cm 거리에서 3초 동안 압축 공기로 건조시키거나 마른 cotton, 젖은 cotton, microbrush, absorbent tissue paper로 건조시키면 상아질이 적절하게 건조됨을 확인할 수 있었다.

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열분해에 의한 폐인조대리석으로부터 산화알루미늄 회수에 관한 연구 (A Study on Recovery of Aluminum Oxide from Artificial Marble Waste by Pyrolysis)

  • 김복련;김창우;서양곤;이용순
    • Korean Chemical Engineering Research
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    • 제50권3호
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    • pp.567-573
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    • 2012
  • 인조대리석은 천연대리석에 비해 우수한 외형, 높은 마감도, 고른 빛깔, 압력과 마모에 대한 우수한 저항성, 부식과 풍화에 대한 우수한 저항성 등의 장점을 가지고 있다. 그래서 인조대리석은 주방용 조리대, 욕실 세면대, 가구, 안내 데스크 등에 다양하게 사용되고 있다. 그러나 인조대리석을 자르고 마감하는 과정에서 많은 양의 폐기물들이 스크랩 또는 분진의 형태로 발생한다. 고급스런 인테리어 재료의 수요의 증가에 따라 인조대리석으로부터의 폐기물은 증가하고 있다. 폐인조대리석은 분쇄, 열분해, 증류공정 등을 통하여 전자재료, 세라믹 등의 원료가 되는 산화알루미늄 및 인조대리석의 원료가 되는 MMA로 재생이 가능하다. 폐인조대리석의 특성을 TGA/DSC 및 원소분석을 통해 그 특성을 분석하였다. 폐인조대리석을 분쇄 및 열분해하여 원 산화알루미늄을 얻었다. 본 연구에서는 원 산화알루미늄을 회수하는 공정의 최적화를 위해 Box-Behnken 실험계획법을 사용하였다. 원 산화알루미늄의 특성치는 색도 분석, 원소 분석 그리고 표면적 등에 의하여 평가하였다.