• 대한화학회지
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• 제39권7호
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• pp.524-529
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• 1995

pH 1에서 15-crown-5(SGBM)을 결합시킨 silica gel를 고정상으로 하는 액체 크로마토그래피을 이용하여 혼합 금속이온 용액으로부터 금속이온들의 분리효율을 결정하였다. 여러가지 SGBM-금속이온들간의 결합상수 및 분리인자들을 측정한 결과 그 순위는 Li(Ⅰ) < Sr(Ⅱ) < Na(Ⅰ) < Cu(Ⅱ) < Mg(Ⅱ) < K(Ⅰ) < Ca(Ⅱ) < Bi(Ⅲ) < Sb(Ⅲ)로 나타났다. 이러한 사실은 금속이온의 크기 효과 및 전자 밀도 효과에 의해서 결정됨을 알 수 있었으며, 또한 알칼리, 알칼리 토금속이온 및 $Cu^{2+}$이 혼합된 용액에서 $Sb^{3+}$의 분리효율이 다른 이온들에 비해서 훨씬 좋게 나타남을 알았다.

• Tribology and Lubricants
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• 제32권5호
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• pp.166-171
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• 2016

Electric vehicle ownership is expanding for two reasons: its technology features have enhanced fuel economy, and the number of vehicle emissions regulations is increasing. Battery performance has a large influence on the capability of electric vehicles, and even though battery thermal management has been actively researched, specific technological improvements to battery performance are not being presented. For instance, many industrial applications utilize vortex tubes as components for refrigeration machines because of their numerous intrinsic benefits. If electric vehicles incorporate vortex tubes for battery cooling, performance and efficiency advancements are possible. This study uses a counter-flow vortex tube to investigate its temperature separation characteristics, based on the back pressure of the cold air exit and the difference between the inlet and back pressures. The experiment uses a vortex tube with the following parameters: six nozzle holes, a 20 mm inner vortex diameter (D), a 14D tube length, a 0.7D cold exit orifice diameter, and a nozzle area ratio of 0.142. The measurements prove that the temperature difference between the hot air and cold air decreased because of the flow resistance of the hot air and the backflow phenomenon at the cold air exit. The flow resistance causes the temperature difference to decrease, and the back pressure of the cold air exit influences the flow resistance. The results show that the back pressure significantly influences the efficiency of temperature separation.

• Korean Journal of Chemical Engineering
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• 제35권12호
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• pp.2355-2364
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• 2018

We evaluated the effect of particle size and associated dynamics on a hydrocyclone separation process in order to understand the movement of the particle trajectories inside the hydrocyclone via numerical analysis, with particles of acid hydrolysis residues discharged in $TiO_2$ production via the sulfate method as a case study. The values obtained from the numerical simulation were successfully compared with those from experimental tests in the literature, allowing a description of the dynamics of the particles, their acting forces, and their relevant properties together with separation efficiency. The results showed that particle motion is jointly controlled by the drag force, the pressure gradient force and the centrifugal force. With increasing particle size, the influence of the drag force is weakened, whereas that of the centrifugal force and pressure gradient is strengthened. Factors including particle density, slurry viscosity, and inlet slurry flow rate also contribute to a clear and useful understanding of particle motion behavior in the hydrocyclone as a method for improving the separation efficiency.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1505-1509
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• 2006

We use the color separation grating (CSG) to split colored light into the sub-pixel of LCD to enhance the optical efficiency as compared with that of using color filter. Based on the Fresenl diffraction theory, the theoretical optical efficiency can reach 66-81%, ranging almost from 2 to 2.5 times of that using color filters.

• Journal of Advanced Marine Engineering and Technology
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• 제31권8호
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• pp.1028-1034
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• 2007

In order to establish a criteria of solid particle separation performance test on marine centrifugal purifier at factory acceptance test, an investigation had been done on criteria of test standards, regulations and test specifications of purifier manufactures. KS V 7836, fuel oil and lubricating oil purifiers for marine use-centrifugal type, the criteria of solid particle separation is studied in the point of reality, restricts and analysis method. It is proposed that a reasonable criteria and analysis method should be adopted, and the current criteria shall be revised to adequate levels considering reasonable basis and industrial technology levels. Also, the test analysis conceptions, separation efficiency method and particle size restriction method, are reviewed to fulfil separation performance test for marine centrifugal purifiers.

• KSBB Journal
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• 제20권3호
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• pp.192-196
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• 2005

Chromatography has been a method of choice in the separation of complex biological mixtures for the analytical purpose in particular for the last half of century. In current years, chromatographic method extends its use to the preparative separation where the productivity per resin amount and solvent use become a matter of concern. Recently, simulated moving bed (SMB) method which claims high separation efficiency of the ideal counter-current moving bed chromatography has become a workhorse of preparative separation. SMB technology was developed in the early 1960s for large-scale hydrocarbon separation by UOP and approximately 120 Sorbex units have been licensed to date. Recently, SMB separation technology has been successfully extended from hydrocarbons and sugars to fine chemicals, particularly biochemicals, from laboratory to pilot to production plant. In this paper, the current status of SMB and its modifications were reviewed.

• 자원리싸이클링
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• 제15권1호
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• pp.28-36
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• 2006

2004년 이후 EPR 제도의 시행과 더불어 폐플라스틱을 함유한 물질의 소각과 매립을 법으로 규제함에 따라 폐플라스틱 재활용의 필요성이 가중되고 있다. 본 연구는 생활계 폐플라스틱 재활용을 위한 정전선별 기술의 개발을 목적으로, 하전물질과 하전장치를 개발하여 선별효율을 높이고자 하였다. 따라서 우리는 대상 플라스틱의 하전효율과 재질분리에 적합한 하전장치 및 마찰하전형정전선별기를 개발하여 2종 혼합 플라스틱으로부터 PVC를 $99\%$ 이상 제거하였으며, PET와 같이 PVC 함량을 규제하는 경우 최적 실험조건에서 PET 회수율 $80\%$로 PVC를 $99.99\%$ 까지 제거할 수 있는 기술도 개발하였다. 또한 3종 혼합 플라스틱은 $98\%$이상으로 분리하여 플라스틱의 재활용을 높일 수 있는 재질분리 기술을 확립하였다.

• 한국자원리싸이클링학회:학술대회논문집
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• 한국자원리싸이클링학회 2005년도 추계정기총회 및 제26회 학술발표대회 고분자리싸이클링기술 특별심포지엄
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• pp.23-33
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• 2005

2004년 이후 EPR 제도의 시행과 더불어 폐플라스틱을 함유한 물질의 소각과 매립을 법으로 규제함에 함에 따라 폐플라스틱 재활용의 필요성이 가중되고 있다. 본 연구는 생활계 폐플라스틱 재활용을 위한 정전선별 기술개발로써, 하전물질과 하전장치 개발에 따라 선별효율을 높일 수 있다. 따라서 우리는 대상 플라스틱의 하전효율과 재질분리에 적합한 하전장치와 마찰하전형정전선별기 개발하여 2종 혼합 플라스틱으로부터 PVC를 99% 이상 제거하였으며, PET와 같이 PVC 함량을 규제하는 경우 최적 실험조건에서 PET 회수율 80%로 PVC를 99.99% 까지 제거할 수 있는 기술도 개발하였다. 또한 3종 혼합 플라스틱은 98%이상으로 분리하여 플라스틱의 재활용을 높일 수 있는 재질분리 기술을 확립하였다.

• Membrane and Water Treatment
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• 제10권4호
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• pp.277-286
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• 2019

In 2014, the first demineralization plant, using nanofiltration (NF) membrane coupled with renewable energies was realized at Al Annouar high school of Sidi Taibi, Kenitra, Morocco. This project has revealed difficulties related to the membrane performances loss (pressure increase, flux decline, poor water quality of the produced water and increase of energy consumption), as consequences of membrane fouling. To solve this problem, an autopsy of the membrane was done in order to determine the nature and origin of the fouling. The samples of membrane and fouling were then analyzed by scanning electron microscopy using a scanning electron microscope (SEM) connected with an energy dispersive X-ray (EDX) detection system and X-ray diffractometer (XRD). Moreover, three cleaning solutions (hydrochloric acid, nitric acid and sulfuric acid) were tested and assessed in a single cleaning step to find the suitable one for the fouled membrane to regain its initial permeability and performances. The analysis of the experimental results showed that the fouling layer is mainly composed of calcium carbonate (inorganic fouling). Results showed also that the permeability is improved by the hydrochloric acid cleaning (pH=3) with a cleaning efficiency of 93%. Cleaning efficiency did not exceed 75 % with nitric acid (pH=3) and 40 % with sulfuric acid (pH=3).

• 전기학회논문지P
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• 제66권4호
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• pp.163-168
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• 2017

This paper presented an evaluation method for the efficiency uncertainty of a three-phase induction motor using finite element analysis. The motor efficiency in the finite element analysis is calculated by the loss separation method as in the actual test. In the process of evaluating the efficiency uncertainty, the difference between the finite element analysis and the actual test is the method of calculating the type-A / B standard uncertainty of the input quantity to estimate the efficiency and each losses. For the input quantities which can confirm the instantaneous values with respect to time, the type-A standard uncertainty in the finite element analysis is calculated from the RMS values or average values having separate periods in the steady state. And, the type-B standard uncertainty in the finite element analysis is assumed to be zero. Also, this paper compared and analyzed the efficiency uncertainty evaluated by the proposed method and the efficiency uncertainty through the actual test.