• 제목/요약/키워드: Environment-free

검색결과 2,085건 처리시간 0.039초

에틸렌 글리콜법을 이용한 전기로 환원슬래그의 Free CaO 정량 평가에 관한 연구 (Quantitative Evaluation of Free CaO in Electric Arc Furnace Reduction Slag using the Ethylene Glycol Method)

  • 권성준;임희섭;이한승
    • 한국건축시공학회지
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    • 제18권4호
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    • pp.321-327
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    • 2018
  • 본 논문은 한국 철강 생산업체에서 발생되고 있는 ERS의 free CaO를Ethylene glycol법을 이용하여 정량 평가하였다. ERS 생산업체 2곳을 선정하여 ERS의 물리적 특성 및 화학성분 분석을 비교하였으며, Ethylene glycol법을 이용하여 생산업체별, 입경 차이(size), 야적 위치(IN, OUT), 에이징 기간(1day, 7days, 14days, 21days, 28days)에 따른 분류로 free CaO 정량 평가를 진행하였다. 본 연구의 실험결과 ERS의 생산업체별 화학 성분이 일부 차이를 나타내고 있었으며, 야적 위치별, 입경, 에이징 기간에 따른 free CaO의 함량 차이가 나타남을 확인하였다. 이는 free CaO가 비정질 물질로서 에이징 기간이 증가하여도 결정화 되지 못한 것으로 사료된다.

생비골 유리 피판술을 이용한 수부의 복합조직 결손의 재건 (Reconstruction of Composite Defect of Hand with Two Segmented Osteocutaneous Fibular Free Flap)

  • 탁관철;강상윤;박윤규;이훈범;박병윤
    • Archives of Reconstructive Microsurgery
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    • 제9권1호
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    • pp.44-48
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    • 2000
  • The advent of free bone flaps has made successful replacement of extensive areas of bone loss in the upper and lower extremities. The microvascular free bone flaps have faster healing without bony absorption or atrophy and can heal in the hostile environment of scarred bed or infection. Since the fibula free flap introduced by Taylor and colleague in 1975, it has been used extensively for skeletal reconstruction of extremities. In 1988, the folded vascularized fibula free flap was first described as a technique to reconstruct significant long bone defect of upper and lower extremities. During the same time, the fibular free flap has evolved to become most preferred choice of mandibular reconstruction. Up to present day, few reports have been made on the fibular free flap used for reconstruction of injured hand containing metacarpal bone and soft tissue defect. We present here our new and unique experiences with vascularized fibular osteocutaneous free flap as useful and satisfactory one for reconstruction of hand with composite defects.

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Soraphinol C, a New Free-Radical Scavenger from Sorangium cellulosum

  • Li, Xuemei;Yu, Tae-Kyung;Kwak, Jong-Hwan;Son, Byoung-Yil;Seo, Young-Wan;Zee, Ok-Pyo;Ahn, Jong-Woong
    • Journal of Microbiology and Biotechnology
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    • 제18권3호
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    • pp.520-522
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    • 2008
  • A new compound named soraphinol C (1) was isolated from myxobacteria Sorangium cellulosum KM1001 a soil isolate, together with a structurally related known compound, 4-hydroxysattabacin (2). These compounds were isolated by silica gel column chromatography and recycling preparative HPLC, consecutively. The structures of the compounds were determined on the basis of combined spectroscopic analyses. Compounds 1 and 2 exhibited antioxidant activity as a radical scavenger in the experiment using a hydrophilic free-radical initiator, 2,2'-azobis(2-amidinopropane)dihydrochloride with ORAC values of 0.956 and 0.617, respectively.

실험적 모드해석법에 의한 이중바닥구조의 동특성 해석 (Experimental Model Analysis of Double Floor)

  • 변근주;노병철;이헌주;이호범
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1993년도 가을 학술발표회 논문집
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    • pp.207-212
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    • 1993
  • When constructing highly precise production plants, for example, super LSI plants or semiconductor plants, it is important to take the necessary control countermeasures into consideration to obtain the working microvibration environment, which is directly related to product precision. Working environment of a clean room means vibration-free and there are only ultra-miro vibration which human cannot sense. In order to provide an place having a vibration-free working environment with only ultra-micro vibration it is necessary to posses a great number of vibration isolation technlogies, wide-ranging and abundant survey and teat data, and a high level of knowledge enabling comprehensive judgments to be made. In this study, experimental modal analysis is used to analyze the dynamic characteristics of double floor for vibration-proofing near apparatus which generate vibration. It is concluded that the double floor system with rubber pad inserted between floor panel and pedestal is good for vibration proof.

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톱밥재배에 의한 목이의 자실체 생산 (Fruit-body Production of Auricularia auricula-judae by Sawdust Cultivation)

  • 조우식;황억금;강민진;최성용
    • 한국균학회지
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    • 제38권1호
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    • pp.5-7
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    • 2010
  • Auricularia auricula-judae is an edible mushroom, which is known as wood ear, free ear, black ear mushroom, and free jelly fish. Present experiments were conducted to determine the possibility of artificial cultivation with oak sawdust of A. auricula-judae. The duration of mycelial growth and days of pinhead formation on oak sawdust bag (1.4 kg) were 29~32 days and 13~17 days, respectively. The yield of fresh fruit-body was 275~350 g.

A New Free-Living Marine Nematode, Chaetonema longicorpus sp. nov. (Enoplida: Anoplostomatidae) from a Subtidal Zone of the East Sea, Korea

  • Lee, Hyo Jin;Lee, Heegab;Rho, Hyun Soo
    • Animal Systematics, Evolution and Diversity
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    • 제38권4호
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    • pp.205-213
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    • 2022
  • A new free-living marine nematode, Chaetonema longicorpus sp. nov., was discovered in a subtidal benthic habitat around the Uljin nuclear power plant in the East Sea. Chaetonema longicorpus sp. nov. differs from other Chaetonema species in its very long body length, relatively long cephalic setae, long and narrow buccal cavity, bottle-shaped amphideal fovea, short spicules, only one pre-cloacal seta instead of a pre-cloacal supplement, and conspicuous ventral swelling at the middle of the tail. Herein, we provide a taxonomic description and illustrations of this new species using differential interference contrast microscopy. Furthermore, an illustrated pictorial key to all valid species, including the new species and comparative tables on the biogeographical and morphological characteristics of the genus Chaetonema, are provided.

연속회분반응기의 아질산 축적 특성과 질산화 및 탈질 미생물의 정량적 분포 연구 (Nitrite Accumulation Characteristics and Quantitative Analyses of Nitrifying and Denitrifying Bacteria in a Sequencing Batch Reactor)

  • 김동진;권현진;윤정이;차기철
    • 한국물환경학회지
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    • 제24권3호
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    • pp.383-390
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    • 2008
  • Recently, the interests on economical nitrogen removal from wastewater are growing. As a method of the novel nitrogen removal technology, nitrogen removal via nitrite pathway by selective inhibition of free ammonia and free nitrous acid on nitrite oxidizing bacteria have been intensively studied. The inhibition effects of free ammonia and free nitrous acid are low when domestic wastewater is used, however, because of its relatively lower nitrogen concentration than the wastewater from industry and landfill, etc. In this study, a sequencing batch reactor (SBR) is proposed for nitrogen removal to investigate the effect of the low nitrogen concentration on nitrite accumulation. Nitrification efficiency reached almost 100% during the aerobic cycle and the maximum specific nitrification rate ($V_{max,nit}$) reached $17.8mg\;NH_4{^+}-N/g\;MLVSS{\bullet}h$. During the anoxic cycle, average denitrification efficiency reached 87% and the maximum specific denitrification rate ($V_{max,den}$) reached $9.8mg\;NO_3{^-}-N/g\;MLVSS{\bullet}h$. From the analysis the main reason of nitrite accumulation in the SBR was free nitrous acid rather than free ammonia. Nitrite accumulation increased with the decrease of organic content in the wastewater and the mechanism is not well understood yet. From the result of fluorescent in situ hybridization, the distribution of nitrite oxidizing bacteria was in equilibrium with ammonium oxidizing bacteria when nitrite accumulation did not occur.

군산자유무역지대 활성화를 위한 개발방향 구조분석에 관한 연구 (A Structural Analysis of Developing Strategies for Activation in Gunsan Free Trade Zone)

  • 여기태
    • 한국항해항만학회지
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    • 제27권5호
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    • pp.569-576
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    • 2003
  • 우리나라가 속해 있는 동북아지역은 동남아시아와 더불어 세계 물류의 중심지 및 생산공장의 역할을 수행하고 있다. 특히 동북아시아를 선도하고 있는 한국, 중국, 일본의 경우 동아시아의 물류 거점역활 선점과 글로벌기업 유치를 위하여 다양한 Free Zone제도를 제정 도입하여 활성화에 노력을 기울이고 있다. 이러한 상황에서 동 제도의 시행초기 단계에 있는 우리나라의 경우, 주변국을 벤치마킹하여 성공요인을 찾는 것이 시행착오를 줄이고 경쟁의 우위를 확보하는 지름길이 될 것이다. 한편, 주변국의 Free Zone들은 다양한 전략을 가지고 경쟁을 하고 있으나, 우리나라의 경우 자유무역지대 활성화 전략에 포함되는 구성요소간의 종속관계, 계층파악 등의 시스템 적인 차원에서의 접근은 전무한 실정이다. 따라서 본 논문은 이러한 점에 착안하여, 군산 자유무역지대(Free Trade Zone) 성공요인을 파악하고, 이를 바탕으로 하여 군산자유무역지대 활성화를 위한 구조모델을 FSM법을 사용하여 구축하는 것을 연구의 목적으로 하였다.

저중력 환경 모사를 위한 낙하 시험 방법 연구 (Investigation of Drop Test Method for Simulation of Low Gravity Environment)

  • 백승환;유이상;신재현;박광근;정영석;조기주;오승협
    • 한국추진공학회지
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    • 제25권4호
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    • pp.78-87
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    • 2021
  • KSLV 상단의 임무 다각화를 위해서는 저중력 환경에서 액체 추진제의 거동을 정확히 파악하고 있어야 한다. 지상에서 저중력 환경을 모사하는 방법은 자유낙하 방법이 있지만, 공기저항이 항상 동반된다. 공기 저항을 제거하기 위하여 공기 저항 차단캡슐을 이용한 낙하 시험을 진행하였다. 공기 저항 차단캡슐 내부에 시험체를 위치하고 7 m 높이에서 1.2초 동안 낙하하여 시험체의 저중력 환경을 조성하였다. 낙하하는 동안 0.01 g 이하의 중력가속도를 측정하였으며 지표면에 도달하기 전 최소 가속도는 약 0.005 g였다. 추후 낙하 높이 및 낙하 시간이 증가한다면 개선될 수 여지가 있다.

비중선별(比重選別) 현미중(玄米中) 유리 Amino산 함량 (Free amino acids of brown rice in relation to specific gravity grade)

  • 박훈;전재근;조인호
    • Applied Biological Chemistry
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    • 제15권1호
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    • pp.35-40
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    • 1972
  • The contents of free amino acids in deembryod brown rice of two varieties were investigated by amino acid autoanalizer in relation to specific gravity grade. The analytical methods of free amino acid were also discussed. 1) The lower the specific gravity of the unhulled rice the higher the content of total free amino acids in the deembryod brown rice, and the similar trend appears to hold on each amino acids. 2) Main free amino acids were serine+asparagine, glutamic acid, aspartic acid, alanine and valine, and maximum values of them were 7.3, 5.1, 4.0, 3.4, 0.9mg/100g rice, respectively. They consist about 85% of total free amino acids in most cases. 3) The contents of soluble nitrogen and free amino acids appear to be lower in high protein variety (IR 667) than in low protein variety (Jinhung). The percentage of free amino acid nitrogen to soluble nitrogen, however, appears to be higher in high protein variety (IR 667). 4) Alanine was much lower than aspartic acid in IR 667 having Indica blood while alanine appears to be higher than aspartic acid in Jinhung (Japonica rice) suggesting varietal difference in amino acid metabolism. 5) Threonine peak was overlaped with glutamine, and serine was with asparagine in this study.

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