• 제목/요약/키워드: powder application method

검색결과 300건 처리시간 0.026초

알루미나 여과막의 상전이와 미세구조 변화 (Phase Transformation and Microstructural Change of Alumina Membrane)

  • 정훈;최덕균;정덕수
    • 한국재료학회지
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    • 제10권9호
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    • pp.619-623
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    • 2000
  • 알루미나 여과막은 boehmite 분말 (${\Upsilon}-AlOOH$)을 이용하여 졸-겔법으로 준비되어졌다. 제조된 여과막은 상전이 온도와 미세구조 변화를 관찰하기 위해 지지체 없이 형성된 여과막을 제조하였다. 여과 공정의 응용에서 균일한 기공크기와 분포를 제어하는 것이 중용하다. 다공성 담체 위에 형성된 여과막과 다공성 담체 없이 형성된 여과막의 ${\theta}-to\;{\alpha}-AL_2O_3$로의 상전이는 박막 XRD를 이용하여 분석하였고, 미세구조의 변화의 관찰은 주사전자현미경(SEM)을 사용하여 관찰하였다. XRD에서 분석된 결과는 다공성 담체 위에 형성된 여과막이 다공성 담체 없이 형성된 여과막과 비교하여 $100^{\circ}C$ 더 높은 상전이 온도를 가지는 것을 보여주었다. 이런 유사한 효과는 여과막의 미세구조 변화에서도 관찰되었다.

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고령자를 위한 영양강화 유제품 개발 II. 고령자 영양강화 적용 기술 현황 (Application of Dairy Food Processing Technology Supplemented with Enriched-nutrients for the Elderly: II. The Applicable Technology of Carefoods for the Elderly)

  • 김범근;장혜원;최가희;문용일;오세종;박동준
    • Journal of Dairy Science and Biotechnology
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    • 제37권4호
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    • pp.213-222
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    • 2019
  • Milk and dairy products are the high value foods for the elderly population. In particular, fermented milk is the best source of calcium for people in the specific age group of over 79 years. It provides a good source of protein. Regular exercise and active lifestyle are recommended to slow down the muscle loss. However, exercising without proper nutrient intake is simply not sufficient at this age. Milk and dairy products provide the iron and protein content required for effective exercise-assisted growth. Milk nutrients have the advantage of being produced in various food forms, such as liquid, semi-solid, and powder types. Fat-soluble vitamins such as retinol and vitamin K can be encapsulated using various technologies for milk and dairy products. Using the encapsulation method, spray drying and fluidized-bed coating have been used for adding the micro-nutrients to the food. Microencapsulation technology is being applied in case of the fermented dairy products too. In particular, various wall materials are being developed to enhance the viability of probiotics. In the near future, advanced high-efficiency technologies that can effectively nourish the dairy products with nutrients will be developed to produce targeted high-nutrition value food for the elderly.

Photocatalytic removal of NOx using TiO2-coated zeolite

  • Mendoza, Joseph Albert;Lee, Dong Hoon;Kang, Joo-Hyon
    • Environmental Engineering Research
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    • 제21권3호
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    • pp.291-296
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    • 2016
  • Application of photocatalytic nanoparticles has been recently gaining an increased attention as air purifying material for sustainable urban development. The present work reports the photocatalytic removal of gaseous phase nitrogen oxides ($NO_x$) using $TiO_2$-coated zeolite to be applied as a filter media for the urban green infrastructure such as raingardens. The $TiO_2$-coated zeolite was synthesized by simple wet chemistry method and tested in a continuous-flow photo-reactor for its removal efficiency of $NO_x$ under different conditions of the weight percentage of $TiO_2$ coated on the zeolite, and gas retention time. The removal efficiency of $NO_x$ in general increased as the weight percentage of $TiO_2$ coated on the zeolite increased up to 15-20%. Greater than 90% of $NO_x$ was removed at a retention time of one minute using the $TiO_2$-coated zeolite ($TiO_2$ weight percentage = 20%). Overall, $TiO_2$-coated zeolite showed greater efficiency of $NO_x$ removal compared to $TiO_2$ powder probably by providing additional reaction sites from the porous structure of zeolite. It was presumed that the degradation of $NO_x$ is attributed to both the physical adsorption and photocatalytic oxidation that could simultaneously occur at the catalyst surface.

"동의보감(東醫寶鑑).내경편(內景篇)"에 나타난 소금에 관한 연구(硏究) (Studies on the Application of Salt of "Donguibogam-Naegyeong(東醫寶鑑-內景篇)")

  • 지명순;김용진
    • 대한한의학원전학회지
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    • 제23권6호
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    • pp.97-108
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    • 2010
  • Salt is a vital inorganic substance to human body and is seasoning in food. It is an absolute alternating factor on fermented food. What's more, in the oriental medicine, it is widely used to raise the pharmacological effect as a component of a prescription when processing a medicine, and when taking the medicine. Though, Importance of salt is often unaware and it is not used in the right way. focusing on "東醫寶鑑 內景篇 Donguibogam-Naegyeong" I categorized the methods of salt's prescription, dose, processing, seasoning, etc. The contents were compared and studied as well. When salt is used as a medicine, It is used as a main medicine, complimentary(aid) medicine, Jjim-Jil(hot towel or bath etc), vomiting medicine and gargling water. when taking the salt water with other medicine, depending on the type of the medicine, boiled salt water, warm alcohol or salt water, mixing powder medicine with salt water etc The methods are diverse. The reason to process medicine with salt or salt water is to bring the pharmacological Qi(energy) down to increase remedial value. When processing a medicine, kneading dough with salt water and the case using food ingredient as medicine salt was used as seasoning. Kneaded mud with salt were used to cover medicine or on the outer surface. This proves that it prevents the dryness and helps the medicine cooked even. Like this, salt is vital and highly-valued medicine in the oriental medicine. learning the right method of using salt and if it were used properly It is considered that it would increase the Pharmacological effect.

수도(水稻)에 대(對)한 질소(窒素), 가리(加里) 복비추비(複肥追肥) 효과시험(效果試驗) (Effect of N-K Compound Fertilizer Top Dressing of Paddy)

  • 오왕근;이강만;김우진
    • 한국토양비료학회지
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    • 제12권3호
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    • pp.133-139
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    • 1979
  • 수도추비용(水稻追肥用)으로 시제(試製)된 NK 복비(複肥) 17-0-17 (입상(粒狀) 및 분말상(粉末狀))과 17-0-14의 효과를 단비(單肥)(요소(尿素) 및 염화가리(鹽化加里))와 비교(比較)하기 위하여 신품종 수도(水稻)(밀량 23호)를 써서 포장시험(圃場試驗)을 실시(實施)했든바 그결과(結果)를 요약(要約)하면 다음과 같다. 1. 수량면(收量面)에서 볼때 복비수비(複肥穗肥)는 단비수비(單肥穗肥)보다 더 효과적인 경향(傾向)이 였다. 2. 입상(粒狀) 17-0-17 수비구(穗肥區)에서 K 및 N의 흡수(吸收)가 타구(他區)에 비(比)해 많았으며 K/(Ca+Mg)값도 높았다. 3. 복비구(複肥區)에서 가리(加里)와 질소흡수량(窒素吸收量)이 많았든 원인(原因)에 대(對)해서는 본시험(本試驗)성적만으로 설명(說明)이 어려웠다. 4. N-K복비(複肥)는 수비(穗肥)로 뿐만아니라 수도(水稻)에 대(對)한 즉(卽) 기비(基肥) 유효분벽기(有效分蘗期)나 최고분벽기(最高分蘗期)에 추비(追肥) 하여도 그 효과(效果)를 검토(檢討)해볼 만 할것 같다.

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초등학교 학생들의 자기장 개념 분석과 인지양식의 차이에 따른 대안실험의 효과 (The Effect of an Alternative Experiment for the Formation of Student's Conceptions about the Magnetic Fields of a Permanent Magnet by Cognitive Styles)

  • 오광택;윤석주
    • 한국자기학회지
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    • 제26권5호
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    • pp.159-167
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    • 2016
  • 초등학교 6학년 과학교과 영구자석 주위의 자기장에 대한 학습에서 나타나는 학생들의 자기장 개념 유형을 조사하였다. 그리고 학생들의 영구자석 주위의 자기장에 대한 오개념 개선을 위한 나침반을 사용하는 대안실험을 제안하였으며 학생들의 인지양식에 따른 효과를 비교하였다. 영구자석 주위에 철가루를 뿌려 관찰한 자기장에 대해 부분 분포 모형, 극 분리 모형, 균질 분포 모형, 장 모형의 4가지 개념 모형이 나타났으며, 영구자석과 나침반을 이용하여 자기장을 관찰한 실험에서는 철가루 실험에서 나타났던 자기장 모형들이 연속, 변형, 복잡화되었는데 극 분리 모형, 복합 균질 분포 모형, 장 모형의 3가지 자기장 개념 모형으로 나타났다. 대안실험을 통해서 올바른 자기장 개념의 형성 비율이 장의존적인 학생들에게 유의미하게 높은 것으로 나타났다.

Al2O3:xCr2O3 고용상의 발광특성과 적색형광체의 연색성 향상을 위한 첨가제로의 응용 (Photoluminescence of Al2O3:xCr2O3 Solid Solution and Application as the Additive for Improving CRI of Red Phosphor)

  • 채기웅;천채일;김정석
    • 한국세라믹학회지
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    • 제47권2호
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    • pp.122-126
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    • 2010
  • In this article photoluminescence of the $Al_2O_3:xCr_2O_3$ solid solutions prepared by solid state reaction method are represented. The effect of $Cr_2O_3$-activator concentration and heat treatment time on the PL characteristics have been discussed in conjunction with microstructure of phosphor samples. The $Al_2O_3:xCr_2O_3$ phosphors show the highest PL intensity at x=0.003 mole when the samples are reacted at $1600^{\circ}C$ for 5 h. The PL emission and absorption spectra show the maximum peaks at 698 nm and at 398 nm respectively. The CIE color coordinate is (x=0.646, y=0.316) at 0.003 mole $Cr_2O_3$, which value is very close to the NTSC coordinate of red color. This characteristic feature of $Al_2O_3:xCr_2O_3$ has been applied for an additive to improve the color characteristic of other red phosphor $LiEuW_2O_8$ which has a relatively poor color purity with an emission peak centered at 615 nm and with a CIE coordinate (x=0.530, y=0.280). The $Al_2O_3:0.003Cr_2O_3$ phosphor has been mixed with the $LiEuW_2O_8$ phosphor powder and the PL characteristics and CIE color coordinates are characterized. The $Al_2O_3:xCr_2O_3$ phosphor was found effective for improving the CRI (color rendering index) of $LiEuW_2O_8$ phosphor.

순환자원을 활용한 환경친화형 콘크리트 블록 제조 (Manufacturing of Eco-Friend Concrete Block using Recycled Materials)

  • 이재진;한천구
    • 한국건설순환자원학회논문집
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    • 제5권4호
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    • pp.389-394
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    • 2017
  • 본 연구는 콘크리트 블록을 생산하는 공장에서 경제적이면서 환경 친화적인 블록을 생산하기 위해 산업부산물 자원을 효과적으로 이용하는 방안에 관한 것이다. 즉, BS 3종에 일라이트, 탈황석고 및 폐내화물울 치환하여 종전에 연구되었던 결과에서 양호한 것으로 밝혀진 몇 개 변수를 Mock-up 시험성격으로 실제 생산라인에서 호안블록을 생산하여 그 특성을 분석하므로써 최적 조합을 확정하고자 한다. 실험결과 압축강도, 흡수율, 내동해성 및 수질영향의 pH 관점에서 고려하면 BS 3종에 정제 탈황석고 5% 치환 및 여기에 골재로서 일라이트를 1% 치환한 배합이 최적인 것으로 분석되었다. 그러나 일라이트는 시멘트 보다 고가이므로 경제적인 측면까지도 고려하면 BS 3종에 5%의 정제 탈황석고를 결합재로 치환하는 배합이 최적 조합인 것으로 밝혀졌다.

재래 묵염방법에 따른 피염물의 색상과 색차 분석 (Analysis of Color and Color Differences of Dyed Articles According to the Traditional Techniques of Dyeing Buddhist Priests' Robes)

  • 김종태;황춘섭;박민여
    • 복식
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    • 제60권2호
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    • pp.68-80
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    • 2010
  • In order to get the information needed for the preservation and application of Korean traditional dyeing techniques to modern textiles products, the present study analyzed the color and color differences of dyed goods according to the contents of fabrics and the traditional techniques of dyeing the Buddhist priests' robes. A spectrophotometer was used to measure the differences in achromatic color according to dyeing techniques, dyestuff, kinds of dyed fabrics, and after-treatment methods. Through experiments based on the traditional dyeing techniques used by Korean Buddhist priests, a total of 144 pieces of dyed fabrics were made and all the colors of those 144 pieces were analyzed. Among three dyeing techniques tested; (1) dyeing with a dye-bath made of ink stick that was ground down with water, (2) dyeing with a dye-bath made by shaking a bag containing ink powder in water, and (3) dyeing with a dye-bath made by rubbing a boiled ink stick on a fabric, dyeing with a dye-bath made of ink stick that was ground down with water was shown to be the best technique in terms of coloring. For fabrics, ramie was the best of all three techniques in terms of making achromatic color. Starching and rubbing was the most effective after-treatment method used on both fabrics dyed with a grounded ink stick and on fabrics dyed by rubbing a boiled ink stick on them. As a whole, yangyeonmook, made from minerals' soot, is better than songyeonmook, which is made by burning old pine trees or yooyeonmook, which is made by burning oils from seeds. Therefore, yangyeonmook could help to preserve and utilize the traditional dyeing techniques of Korea in a practical way in modern life.

주철(鑄鐵)의 침붕조직(浸硼組織)에 관(關)한 연구(硏究) (A Study on the Borided Stsucture of Cast Iron)

  • 김형수;나형용
    • 한국주조공학회지
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    • 제2권3호
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    • pp.2-15
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    • 1982
  • In this study, the influenced of graphite shape on the boriding of cast iron and boride structure was investigated. Gray cast iron, ferritic and pearlitic ductile cast iron were borided at 750,850,900 and $950^{\circ}C$ for 1,3 and 5 hours by powder pack method with the mixture of $B_4C_9\;Na_2B_4O_7$, $KBF_4$ and Shc. The boride layer was consisted of FeB(little), $Fe_2B$ (main) and graphite. Some possibility of the existence of unknown Fe-B-C compound in the boride layer was suggested. And precipitates in the diffusion zone was $Fe_3(B,C)$. The concentration of Si and precipitation of $Fe_3(B,C)$ in the ${\alpha}$ layer raised the hardness of this Zone. The depth and hardness of boride layer increased with the increase of treating temperature and tim. But high temperature (over $950^{\circ}C)$ caused pore at graphite position and long treating time (5hrs) sometimes caused formation of graphite layer beneath the boride layer. So, for the practical application of borided cast iron, treating in short time and at low temperature was recommended. And for ductile cast iron, ferritizing or pearlitizing heat treatment was seemmed to be possible at the same time with boriding. The graphite in the boride layer was deeply concerned with the qualitx and characteristics of the boride layer. And it greatly influenced on the shape of the boride phase, structure of the boride layer. Generally speaking, the existance of graphite restrained the growth of the boride phase. But the boundary between the gsaphite and the matrix acted as the shortcut of boron diffusion. So, for gray cast iron, the graphite layed length-wise led the formation of boride layer.

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