• 자원리싸이클링
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• 제16권1호
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• pp.28-36
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• 2007

폐 ITO 타겟을 염산에 용해시킨 복합 산용액을 원료로 하여 자체기술에 의해 개발한 분무열분해 반응장치를 통하여 평균입도가 50nm이하인 나노 ITO 분말을 제조하였으며, 반응온도 및 원료용액의 농도 등의 반응인자들의 변화에 따른 ITO 분말의 특성을 파악하였다. 반응온도가 $800^{\circ}C$로부터 $1100^{\circ}C$로 변화함에 따라 생성된 ITO 분말의 평균 입도는 40nm로부터 100nm정도까지 증가하고 있었으며, 조직도 점점 치밀화되면서 각각의 입자들이 독립된 다각형 형태를 나타내었으며, 입도분포는 더욱 불균일하게 나타나고 있었다. 또한 반응온도 증가에 따라 XRD 피크의 강도는 증가하였으며 비표면적은 감소하고 있었다. 원료용액 내의 인듐 성분의 농도가 50g/l로부터 400g/l로 증가됨에 따라 생성된 ITO 분말의 평균입도는 점점 증가하는 반면 입도분포는 더욱 불균일 하였다. 농도가 50g/l인 경우에는 ITO 분말의 평균입도는 30nm 이하이면서 입도분포는 비교적 균일하게 나타나고 있었다. 반면 농도가 포화농도에 가까운 400g/l인 경우에는 분말들의 입도분포는 20nm 정도부터 100nm 이상까지 공존하는 매우 불균일한 형태를 나타내고 있었다. 농도가 증가함에 따라 XRD 피크의 강도는 점점 증가하였으며 비표면적은 점점 감소하였다.

• 한국식품영양과학회지
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• 제37권3호
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• pp.367-372
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• 2008

본 연구는 발효정도가 다른 가루녹차 첨가가 유과의 저장 중 품질특성에 미치는 영향을 평가하기 위해 불발효차(부초차, 옥로차), 반발효차(오룡차), 발효차(홍차)를 첨가하여 유과를 제조하였다. 제조된 유과샘플들은 수분, 조지방 함량 측정, 조직감 분석, TBA 측정, 관능평가에 사용하였다. 수분 및 조지방 함량에 있어 각각의 실험구들간의 유의적인 차이는 없었으며 조직감 역시 실험구들간의 유의적 차이는 없었다. 또한 가루녹차가 첨가된 모든 실험구들에서 저장기간 동안 TBA 값의 증가가 대조구에 비해 유의적으로 낮게 나타났으며, 특히 불발효차의 항산화 효과가 가장 높은 것으로 나타났다. 그러나 종합적인 관능적 수용도에 있어 불발효차가 반발효차와 발효차보다 유의적으로 높게 나타났다. 이상의 결과를 종합하여 볼 때, 불발효차 첨가가 유과 제조 시 품질 및 저장성 향상에 기여할 것으로 판단되었다.

• 한국구조물진단유지관리공학회 논문집
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• 제23권1호
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• pp.102-112
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• 2019

본 연구는 PVA(polyvinyl alcohol) 섬유와 VAE(vinyl acetate ethylene) 분말 폴리머를 사용한 시멘트복합체의 압축 휨강도 와 온도변화에 따른 충격파괴거동을 연구하였다. 충격시험은 $-35^{\circ}C$, $0^{\circ}C$ 및 $35^{\circ}C$의 선정된 온도조건에서 실시하였다. 본 실험에서는 시멘트 복합체와 일반 모르타르에 대한 충격파괴 에너지와 변위, 시간을 얻기 위해 낙하 충격시험기(Ceast 9350)를 사용하여 충격시험을 수행하였다. 강도시험결과, PVA 섬유와 VAE 분말 폴리머의 휨강도는 모두 증가하였다. PVA 섬유보강 시멘트복합체의 경우 재령 28일에서의 압축강도는 약간 감소하였으나, 휨강도는 일반 모르타르 강도보다 24.4% 증가하였다. 낙하 충격시험 결과, PVA 섬유보강 시멘트복합체 시편은 섬유의 가교역할로 인한 균열발생의 억제와 에너지 분산에 의한 미세균열이 발생하였으며, 충격에 의한 배면파괴와 관통에 대하여 억제되었다. 반면 VAE 분말 폴리머 시멘트복합체와 일반 모르타르의 시편은 대부분 큰 균열이나 관통파괴 되었다. 충격하중을 받는 시멘트복합체와 일반 모르타르의 시편은 대부분 국부적인 취성파괴거동을 보이며, PVA 섬유보강에 의한 휨성능 증진으로 인해 충격에 대한 저항성능이 크게 향상되었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 추계 학술논문 발표대회
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• pp.32-33
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• 2016

This purpose of this study is to find the properties of pore structure and length change of blast furnace slag cement added alkali powder stimulant on shrinkage reducing agent presence. In length change, the specimen added alkaline stimulant was smaller than normal blast furnace slag concrete. And the specimen added shrinkage reduction agent was confirmed to show smaller rate of length change than the length. In MIP analysis of 1day-age, 0.1㎛ subsequent pore amount of the specimen added alkaline stimulant was significantly smaller value the normal blast furnace slag concrete specimen.

• 한국표면공학회지
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• 제30권6호
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• pp.400-405
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• 1997

The experimental study has been performed to deposit to deposit chromia powder on magnssium alloy for tribological and mechanical properties. The optimal condition was obtained by changing the spray condition such as working distance and gun power. As ceramics was coated onto the a light metal such as Mg according to the weight reduection of the car engine block, it could acquire that the engine efficiency deu to the weight reduction and properties such as resistance to heat, as well as wear. Coating qualities are discussed with respect to hardness, tribologicalproperty, and microstructure. The tribological and mechanical properties are investigated by using the reciprocal configuration tribometer and microharduess tester. Wear mode is determined by observing the SEM morhpology of wear track and cross section view of wear track.

• 대한가정학회지
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• 제24권4호
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• pp.27-50
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• 1986

The military uniform is worn to defend against enemy. Its function has an important effect on its changing. As once the means of combat was the collective formation, soldiers fought with swords and bows, or on horses. After the invention of gun powder, however, it became changed to the scattering formation. Therefore, it became impossible to fight on great armors any more. the armors and helmets made of iron, used light, materials, became those of Doosuingab (豆錫鱗甲), Soejagab(鎖子甲), Pigab(皮甲), Jigab(紙甲). The Doojunggab(頭釘甲) which presented a grand appearance came into existence. At last the Chullic and GooGoonbok made of clothing were worn. Korean military uniform were influenced by Chines military uniform. Korean armors had an influence on Japanese. As follows, I will study on Chinese and Korean armors with the changes of the times.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.1300-1302
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• 2009

Transparent $Zn_2SiO_4:Mn^{2+}$ film has been synthesized by spray pyrolysis with various spraying conditions. It illuminates an efficient green emission with the relative emission intensity about 45% under 147nm excitation of a commercial powder phosphor. Additionally, the zinc precursors and additives play a key factor both controlling luminous efficiency and transparency.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.186-187
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• 2013

Recently, high fluidity concrete is becoming more prevalent. High fluidity concrete uses admixture or thickener in order to prevent separation of materials due to increased fluidity, and, especially, BS is becoming more use for reduced heat of hydration and improved long-term strength. This study examined the effect of BS on fluidity of cement paste from a rheological viewpoint. As for BS types, materials equivalent to 1 types of KS F 2563 and the cement mass was substituted by 20, 40, 60, 80%.

• 자원환경지질
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• 제18권2호
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• pp.135-138
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• 1985

The radioautographing of U-bearing cloaly slate samples were initiated in order to clarify the uranium distribution patterns in the samples of Ogcheon system. Moreover, x-ray powder diffraction and x-ray single crystal analysis studies were undertaken to identify the uranium mineral which was extracted from U-bearing coaly slate. The handspecimens were collected from the Boseong mine, located in Deokpyeong area, Goesan-gun, Chungcheongbug-do. According to the experimental studies, it has been found the following facts: (1) fixed carbon has close relation with uranium contents, (2) quartz veins developed in U-bearing coaly slate are diveded into two groups based on mode of occurrence, formation stage and uranium distribution pattern; early quartz vein ($QV_1$) with low uranium concentration and late quartz vein ($QV_2$) with high uranium concentration, (3) matrixes around $QV_1$ are displayed homogeneous and high uranium concentration, while matrixes around $QV_2$ are low uranium concentration, (4) uranium mineral is identified as a variety of autunite.

• 대한금속재료학회지
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• 제48권8호
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• pp.775-779
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• 2010

Functionally graded materials (FGM) of PSZ/NiCrAlY on Inconel substrate were fabricated by detonation gun spraying method. A thick ceramic layer generally has a high thermal barrier effect however, because failure often occurs, the use of an FGM layer gives an advantage in thermal property. During the thermal shock test, micro fracture processes were detected by the AE method. Also, the thermal shock test was performed for NFGM, FGM and the changed FGM in the layered composition profile. It was found through AE testing and the observation of fracture surface that FGM was superior to NFGM in thermal shock properties. The linear or metal-rich type FGM in composition profile had the best resisting property among the FGM. It was found that the controlled composition profile of the graded layers had better thermal properties.