• 제목/요약/키워드: binary solution

검색결과 345건 처리시간 0.023초

이성분 나노유체에서의 암모니아 기포 흡수 성능 향상 (Enhancement of $NH_3$ Bubble Absorption Performance in Binary Nanofluids)

  • 정준영;김진경;강용태
    • 설비공학논문집
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    • 제17권4호
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    • pp.312-317
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    • 2005
  • The objectives of this paper are to study the absorption characteristics of $NH_3$ bubbles in the binary nanofluids and to quantify the effects of surfactants and nano-particles on the bubble absorption performance. 2-Ethyl-1-Hexanol, n-Octanol, and 2-Octanol are used as the surfactants and nano-sized $Al_{2}O_3$ and Cu particles are added to make the binary nanofluids into $NH_3/H_{2}O$ solution. The concentration of $NH_3$ solution ($x_s$), the concentration of surfactants ($x_{SA}$), and the mass fraction of nano-particles ($w_{np}$) are considered as key parameters. The experimented ranges of $x_s,\;x_{SA},\;and\;w_{np}$ are $0{\sim}17.92\%,\;0{\sim}1,500\;ppm\;and\;0{\sim}0.2\%$, respectively. The absorption rates are calculated by measuring initial and final weights of test section and exposed time. In addition, the bubble absorption processes are visualized using the shadow graphic method. The results show that the absorption performance is significantly enhanced up to 4 times by adding the surfactants and up to 3 times in the binary nanofluids.

활성탄에서의 H2/CH4/C2H4 순수 기체와 이성분 혼합기체의 흡착평형 (Pure and Binary Mixture Gases Adsorption Equilibria of Hydrogen/Methane/Ethylene on Activated Carbon)

  • 정병만;강석현;최현우;이창하;이병권;최대기
    • Korean Chemical Engineering Research
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    • 제43권3호
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    • pp.371-379
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    • 2005
  • 활성탄 흡착제(Calgon co.)에 대하여 수소, 메탄 그리고 에틸렌의 단일성분 흡착평형과 이들의 혼합가스의 흡착평형을 정적부피법으로 293.15 K, 303.15 K 그리고 313.15 K의 온도와 18 atm의 압력 이하에서 측정하였다. 순수 기체의 흡착등온선을 이용하여 혼합성분의 흡착평형을 예측하였고 실험데이터와 비교하였다. 사용한 모델식은 확대 Langmuir 모델, 확대 Langmuir-Freundlich 모델, 이상 흡착 용액 이론 그리고 빈자리 용액 모델이다. 모델식들은 비교적 정확한 예측치를 보였으며, 이 중 확대 L-F 모델이 혼합 기체의 흡착평형을 다른 모델식보다 좋은 예측결과를 보여줬다.

티타늄 합금 스크랩의 재활용 및 응용 기술 현황 (Recycling and Applications of Titanium Alloy Scraps)

  • 오정민;권한중;임재원
    • 청정기술
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    • 제19권2호
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    • pp.75-83
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    • 2013
  • 본 총설에서는 이원계 티타늄 합금 스크랩을 재활용하기 위해 수소 플라즈마 아크 용해를 이용하여 잉곳을 제조하고, 수소화-탈수소화법과 고상탈산 공정을 통해 저산소 합금 분말을 제조하는 기술에 대하여 소개하고자 한다. 이에 더해, 이원계 티타늄 합금 스크랩을 이용하여 고용상 서메트용 탄화물 분말을 제조하는 응용 분야에 대해서도 소개하고자 한다. 이원계 티타늄 합금 스크랩은 수소 플라즈마 아크 용해를 통해 건전한 잉곳의 제조가 가능함을 확인하였고, 최종적으로 제조된 티타늄 합금 분말의 산소함량은 1,000 ppm 이하였으며, 이를 고용상 서메트용 탄화물 분말의 제조에 응용이 가능함을 확인하였다.

스도쿠 퍼즐을 위한 이진역추적 알고리즘 (Binary Backtracking Algorithm for Sudoku)

  • 이상운
    • 한국인터넷방송통신학회논문지
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    • 제17권4호
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    • pp.155-161
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    • 2017
  • 본 논문은 지금까지 NP-완전 문제로 다항시간 알고리즘이 존재하지 않는 스도쿠 퍼즐 문제의 해를 다항시간으로 구하는 알고리즘을 제안하였다. 제안된 알고리즘은 빈칸들에 [$1,2,{\cdots},9$] 중에서 행, 열과 블록에 존재하는 실마리 숫자를 제외한 후보 집합을 초기치로 설정하였다. 빈칸의 후보 집합에 대해 Stuart이 제시한 기본적인 규칙들과 더불어 2개의 추가 규칙을 제시하고, 마지막으로 이진 역추적 기법(BBT)을 적용하였다. 다양한 부류의 해를 갖는 실험데이터들에 대해 적용한 결과 제안된 BBT 알고리즘은 어떠한 부류의 해를 갖던지에 상관없이 주어진 스도쿠 퍼즐을 풀 수 있음을 보였다.

유전알고리즘과 DNA 코딩을 이용한 Numeric 패턴인식 (Numeric Pattern Recognition Using Genetic Algorithm and DNA coding)

  • 백동화;한승수
    • 한국지능시스템학회논문지
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    • 제13권1호
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    • pp.37-44
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    • 2003
  • 본 논문은 DNA coding 방법과 Genetic Algorithm(GA)을 사용하여 numeric(0~9) 패턴인식 성능을 비교 평가하였다. 이진스트링의 개체 집단 위에서 모의진화를 일으켜 효율적으로 최적 해를 탐색하는 GA와, 생체 분자인 DNA를 계산의 도구 및 정보 저장도구로 사용하며, Adenine(A), Cytosine(C), Guanine(G), Thymine(T)등의 4가지 염기를 사용하는 DNA coding 방법을 이용하여 numeric 패턴인식을 수행하였다. DNA coding 방법과 GA의 성능을 비교 평가하기 위해서 selection, crossover, mutation 등의 GA연산자를 DNA coding에 동일하게 적용하였다. 실험결과, DNA coding 방법은 GA보다 효과적으로 패턴인식을 수행하였다. GA에 비해 DNA coding 방법의 장점은 스트링의 길이가 가변적이고 해의 중복성을 가지며, 4가지 염기를 이용하기 때문에 해 표현이 다양함을 가지고 있다.

A Chemometric Aided UV/Vis Spectroscopic Method for Kinetic Study of Additive Adsorption in Cellulose Fibers

  • Chal, Xin-Sheng;Zhou, Jinghong;Zhu, Hongxiang;Huang, Xiannan
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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    • pp.137-140
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    • 2006
  • This paper describes a technique combining chemometrics with UV spectroscopy for the determination of the concentra tions of two tissue additives (i.e., wet strength and softening agents) in a cellulose fiber containing solution. In single as ent solutions, the concentration of the additive can be measured by UV spectroscopy at the wavelength where the species having absorption. For a binary (i.e., containing two additives) solution system, the spectral characterization is very complicated. However, if aided by a chemometrical calibration technique, each additive in the binary solution can be quantified simultaneously. The present method is very rapid and simple, it can easily perform a continuous measurement in the changes in the additives' concentration after fiber addition, and therefore this becomes a valuable tool for the adsorption kinetics study of chemical additives onto the cellulose fibers. The time-dependent adsorption behaviors of the wet-strength, softening agent, and their both on fiber were also presented.

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쌍화음료 저열량화를 위한 감미료의 관능적 특성(I);아스파탐, 아세로설팜 칼륨, 효소처리 스테비아의 상대 당도 및 쌍화음료에서의 관능적 특성 (Sensory Properties of Low Calorie Ssanhwa Beverages Containing Sweetener(l);Relative Sweetness and Sensory Properties of Ssanghwa Beverages Sweetened with Glucosyl Stevia, Acesulfame-K and Aspartame)

  • 백숙은
    • 한국식품영양학회지
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    • 제21권2호
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    • pp.190-196
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    • 2008
  • This study was performed to aid the development of a reduced-calorie ssanghwa beverage, by using substitutes for high fructose com syrup(HFCS). The relative sweetness levels of HFCS, aspartame, acesulfame-K, and glucosyl stevia solutions were examined in comparison to a 10% sucrose solution in a binary solution model. And the sensory properties of ssanghwa beverages containing aspartame, acesulfame-K, and glucosyl stevia were evaluated at the equi-sweetness to HFCS. In the binary solution model, the relative sweetness of HFCS to sucrose was 0.8, while the values for aspartame, acesulfame-K, and glucosyl stevia were 140, 170, and 100, respectively. Sweet taste and sweet after taste were not significantly different between the HFCS, aspartame, acesulfame-K, and glucosyl stevia solutions. On the other hand, bitter taste, first taste, and overall eating quality were significantly different between the HFCS and aspartame solutions and between the acesulfame-K and glucosyl stevia solutions. Finally, the ssanghwa beverages sweetened with HFCS, acesulfame-K, and aspartame only had slight differences in sensory properties. However, the sensory properties of the beverages sweetened with HFCS and glucosyl stevia, respectively, were significantly different.

이성분 나노유체($H_2O$/LiBr+나노입자)를 적용한 유하박막 흡수기의 열 및 물질전달 촉진 실험 (An Experimental Study on Falling Film Heat and Mass Transfer for Binary Nanofluids ($H_2O$/LiBr+Nanoparticles))

  • 김현대;김성수;남상철;정진희;강용태
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2008년도 하계학술발표대회 논문집
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    • pp.130-135
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    • 2008
  • The objectives of this study are to investigate the combined heat and mass transfer enhancement using binary nanofluids as the working fluids in a $H_2O$/LiBr absorber. The result of heat and mass transfer experiment with the additives(Arabicgum, 2E1H) showed that the heat and mass transfer performance of binary nanofluid with 2E1H enhanced significantly in comparison with that without additive. In the case of 0.01wt% $Al_2O_3$ binary nanofluids with 2E1H, the vapor absorption rate increased up to 77% in comparison with that without additive. The heat transfer rate of 0.01wt% $Al_2O_3$ binary nanofluids with 2E1H increased up to 19%. Based on the experimental results, it is recommended that the $Al_2O_3$ binary nanofluid be good with 2E1H to improve the heat and mass transfer performance.

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Zeta-potential을 이용한 이성분 나노유체의 분산안정도 측정 (Measurement of distribution stability of binary nanofluids by zeta-potential)

  • 이강일;정청우;김현준;정진희;강용태
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2006년도 하계학술발표대회 논문집
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    • pp.52-57
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    • 2006
  • This study investigates the distribution stability of binary nanofluids where binary mixtures such as $NH_3/H_2O$ and $H_2O/LiBr$ solution are used as a base fluid. When a little amount of certain nanosized particles is added into a basefluid, the thermal conductivity of that mixture increases greatly. Such mixtures are named 'nanofluids' where nano-particles should be distributed stably and uniformly so the distribution stability of nanoparticles in nanofluids is one of the most important factors for nanofluid application. Therefore, binary nanofluids in which binary mixtures are applied as the basefluids are considered as working fluids. The kind and the concentration of nanoparticles, and the concentration of ammonia are considered as the key parameters. The objectives of this paper are to visualize the dispersed status of particles in binary nanofluids and to find the effect of key parameters on the distribution stability in the ammonia absorption system.

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Potentiometric studies on Ternary Complexes of Some Heavy Metal lons Containing N-(2-Acetamido)-iminodiacetic and Amino Acids

  • Mahmoud, Mohamed Rafat;Maher Mohamed Ahmed -Hamed;Ahmed, Iman Tawfik
    • Archives of Pharmacal Research
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    • 제16권1호
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    • pp.78-81
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    • 1993
  • Solution equilibria of the thmary systems $UO_2(II)$, La(III), Ce(III)-N-(2-acetamido)-iminodiacetic acid and dicarboxylic amino acids are studied potentiometrically. The formation of 1:1:1 mixed ligand complexes are inferred from the potentiometric titration curves. The formation constants of the different binary and thmary complexes in such system are evaluated at t=$24\pm{0.1}^\circ{C}\;and\;\mu=0.1\;mol\;dm^{-3}(kNO_3)$. It is deduced that the temary complex is more stable than the corresponding binary amino acid anion complex. Moreover, the order og stability of the binary or temary complexes in terms of nature of amino acid and metal ion is investigated and discussed.

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