• BMB Reports
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• 제30권5호
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• pp.346-351
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• 1997

The maximum adsorption/desorption conditions and the adsorption mechanism of globular proteins to vaccine adjuvants were determined. The maximum adsorption ratio of protein to the $Al^{3+}$ content of aluminum oxyhydroxide and the optimal adsorption pH are 2:1 (${\mu}g:{\mu}g$) for bovine serum albumin (BSA) at pH 6.0 and 2.5:1 (${\mu}g:{\mu}g$) for immunoglobulin G (IgG) at pH 7.0, respectively. The maximum adsorption ratio onto aluminum phosphate gel was 1.5:1 (${\mu}g$ Protein:${\mu}g$ $Al^{3+}$) at pH 5.0 for both BSA and IgG. Adsorption of the native globular proteins, BSA and IgG, to aluminum oxyhydroxide and aluminum phosphate gel was reversible as a function of pH. Complete desorption of these proteins from aluminum phosphate gel was observed at alkaline pH, whereas only 80~90% removal from aluminum oxyhydroxide was achieved with alkaline pH and 50 mM phosphate buffer. We conclude that electrostatic and hydrogen bonding interactions between the native proteins and adjuvants are important binding mechanisms for adsorption, and that the surface charge of the protein and the colloid components control the maximum adsorption conditions.

• Journal of Mechanical Science and Technology
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• 제16권10호
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• pp.1336-1345
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• 2002

A triboelectrostatic separation system using a fluidized bed tribocharger for the removal of PVC material in the mixture of PVC/PS plastics is designed and evaluated as a function of electric field strength, air flow rate, and the mixing ratio of two-component mixed plastics. It consists of a fluidized-bed tribocharger, a separation chamber, a collection chamber and a controller. PVC and PS particles can be imparted negative and positive surface charges, respectively, due to the difference in the work function values of plastics suspended in the fluidized-bed tribocharger, and can be separated by passing them through an external electric field. Experimental results show that separation efficiency is strongly dependent on the electric Deld strength and particle mixing ratio. In the optimum conditions of 150 Ipm air flow rate and 2.6 kV/cm electric field strength a highly concentrated PVC (99.1%) can be recovered with a yield of more than 99.2% from the mixture of PVC and PS materials for a single stage of processing.

• 한국세라믹학회지
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• 제40권2호
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• pp.167-171
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• 2003

기계적 방법으로 합성된 CeO$_2$분말을 연마입자로 하여 STI용 CMP 슬러리를 제조하였다. 연마입자는 정전기적 방법과 입체적 방법으로 수계에서 안정화시킬 수 있었으며, 장기 안정성을 위해서는 입체적 방법에 의한 안정화가 유효하였다. 50$0^{\circ}C$와 $700^{\circ}C$에서 합성된 CeO$_2$를 이용하여 CMP 슬러리를 제조하고, SiO$_2$와 Si$_3$N$_4$가 블랭킷 형태로 증착된 웨이퍼를 연마한 결과 연마능률과 선택비는 연마입자의 합성조건과 분산 안정성, 슬러리의 pH 등에 의해 영향을 받았다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.532-537
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• 2000

The purpose of this study is to determine the performance of a commercial air cleaner in removing tobacco smoke indoors. Following injection of tobacco smoke in a room, decay rates for particle concentrations were obtained far mass concentration at each point. The size distribution of the tobacco smoke particles was approximately $1.266{\mu}m$ in mass median diameter with a geometric standard deviation of 1.313. The air cleaner consisted of an electrostatic filtration unit and a fan operated at a flow rate of 5.98 CMM. The collection efficiency for $>1\;{\mu}m$ was more than 99%. Without air cleaner operation, tobacco smoke concentration ratio in room decreased to 30% of initial values within 30 minutes and with air cleaner operation, decreased to 90% of initial values in the test chamber, volume $51.27\;m^3$. Without air cleaner operation, tobacco smoke concentration ratio in room decreased to 10% of initial values within 30 minutes and with air cleaner operation, decreased to 30-70% of initial values in the test chamber, volume $149.2\;m^3$.

• Membrane and Water Treatment
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• 제8권1호
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• pp.73-88
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• 2017

Adsorption kinetics of aqueous ferric ion ($Fe^{3+}$) onto bio-natural rice grains (BRG) have been studied in a batch system. The influence of contact time (0-180 minutes), the dosage of BRG adsorbent (10, 20, 40, and $60gL^{-1}$), and ambient temperature (27, 37, 47, and $57^{\circ}C$) for the adsorption system have been reported. The equilibrium time achieved after 20 minutes of adsorption contact time. The maximum removal of ferric ion is 99% by using $60gL^{-1}$ of BRG, $T=37^{\circ}C$, and $50mgL^{-1}$ ferric ion solution. Adsorption kinetic and diffusion models, such as pseudo-first order, pseudo-second order, and Weber-Morris intra-particle diffusion model, have been used to describe the adsorption rate and mechanism of the ferric ion onto BRG surface. The sorption data results are fitted by Lagergren pseudo-second order model ($R^2=1.0$). The kinetic parameters, rate constant, and sorption capacities have been calculated. The new information in this study suggests that BRG could adsorb ferric ion from water physiosorption during the first 5 minutes. Afterward, the electrostatic interaction between ferric ion and BGR-surface could take place as a very weak chemisorptions process. Thus, there is no significant change could be noticed in the FTIR spectra after adsorption. I recommend producing BGR as a bio-natural filtering material for removing the ferric ion from water.

• 환경위생공학
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• 제17권3호
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• pp.115-120
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• 2002

This study was performed on a questionnaire survey of 500 people about their awareness for indoor air pollution, and measured efficiency of air cleaner which can remove the CO and air-borne particulate of ETS(Environmental Tobacco Smoke) in air clean chamber. The room-size cleaner for measuring indoor air contaminants has been applied to evaluation of two different air cleaner such as the mechanic air cleaner with hepafilter(HPA) and the electrostatic air cleaner with metal plate. The measuring experiment was carried out in a chamber by sampling the air. The results obtained were as follows; As respondents are having their 90% of daytime indoors a day, and 38% of them can feel indoor air pollutions degrees directly by their sense of smell, For the installation of indoor pollution control equipment, 34% of all respondents installed air cleaner because of the problem of economical charge and almost respondents was not satisfied the trust of ability purified indoor air pollutants. In the experimental results, it was found that more than 95% of CD and air-borne particulate of ETS were removed within 20 minutes. The reaction kinetics of removal pollutants was verified as the pseudo-first order, Finally, it appeared that the room-sire air cleaner can be applied to new technology for removing indoor air contaminants.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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• pp.235-238
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• 2004

본 연구는 반도체소자 제조공정에 적용되는 CMP공정 중 LPP(Landing Plug Poly) Contact간의 소자 분리를 위해 진행되는 LPP CMP의 후 세정 과정에서 유발되는 방사형 Defect 제거에 관한 내용이다. 방사형 Defect은 LPP CMP 후에 노출되는 BPSG, Poly, Nitride Film과 연마재로 사용되는SiO2 입자, 후 세정과정에서 적용되는 SC-1, DHF, $NH_4OH$ Chemical과 Brush와의 상호작용에 의해 발생되며, Cleaning시의 산성 분위기 하에서 각 물질간의 pH와 Zeta Potential의 차이에서 기인한다. 이 Defect을 제거하기 위해 LPP CMP후에 Film 표면에 노출되는 각 물질의 표면 특성과 CMP 후 오염입자의 흡착과 재 흡착에 영향을 미치는 Electrostatic force와 Van der Waals force, PVA Brush에 의한 Mechanical force의 상호작용을 고려하여 최적 후 세정 조건을 제시 하였다.

• Korean Chemical Engineering Research
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• 제51권6호
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• pp.666-670
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• 2013

실리콘계 태양전지 제조과정에서 발생하는 불량품에서 실리콘웨이퍼를 회수하는 연구를 수행하였다. 상온($25^{\circ}C$)에서 인산용액 농도, 산성불화암모늄 농도, 킬레이트제 종류 및 농도를 변화시키면서 폐태양전지의 반사방지막 및 N층의 제거 효율을 조사하였다. 10 wt% 인산, 2.0 wt% 산성불화암모늄, 1.5 wt% Hydantoin 사용 시 제거 효율이 가장 우수 하였다. 인산농도가 증가할수록 미세입자의 표면전위가 (+)로 변하여 정전기적 인력에 의해 실리콘웨이퍼 표면에 재흡착하여 표면처리 전보다 두께가 두꺼워졌으며, 표면의 오염도도 증가하였다. 인산-산성불화암모늄-킬레이트제 용액에 의한 표면처리방법은 모든 공정이 상온에서 수행되며, 공정이 단순하고, 폐수 발생량이 적고, 표면제거 효율이 우수한 방법으로 폐 태양전지의 재활용 및 기존 RCA 세정법의 대안으로 가능성이 매우 클 것으로 판단되었다.

• 한국철도학회논문집
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• 제20권4호
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• pp.433-439
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• 2017

도시철도터널은 전동차 운행으로 바닥 먼지가 비산되거나 새로 발생된 마모 먼지로 오염되고 있다. 전동차가 운행하면서 이러한 부유 먼지를 제거하기 위해서 관성집진기인 배플과 전기집진기로 구성된 하이브리드형 집진장치를 개발하였다. 하이브리드형 집진장치의 유량과 집진효율은 서로 반비례하므로, 유량과 집진효율의 관계를 파악하기 위해 2가지 배플 모델을 제작하여 성능을 평가하였다. 유속이 3.4 m/s인 A1 모델을 장착한 집진장치의 $0.5{\mu}m$ 이상인 입자의 집진효율은 30% 이상이었고, 유속이 4.7 m/s인 A2 모델의 경우 20% 이상이었다. 인가전압이 13 kV일 때 1시간 동안 A1 모델 집진장치의 $PM_{10}$ 집진량은 253 mg, A2 모델의 경우 242 mg으로 추정되었다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 추계학술발표대회
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• pp.29.1-29.1
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• 2011

The selective catalytic reduction (SCR) of $MnO_x$ with $NH_3$ is an effective method for the removal of $MnO_x$ from stationary system. The typical catalyst for this method is $V_2O_5-WO_3(MoO_3)/TiO_2$, caused by the high activity and stability. However, This catalyst is active within $300{\sim}400^{\circ}C$ and occurs the pore plugging from the deposition of ammonium sulfate salts on the catalysts surface. It needs to locate the SCR unit after the desulfurizer and electrostatic precipitator without reheating of the flue gas as well as deposition of dust on the catalyst. The manganese oxides supported on titania catalysts have attracted interest because of its high SCR activity at low temperature. The catalytic activity of $MnO_x/TiO_2$ SCR catalyst with different manganese precursors have investigated for low-temperature SCR in terms of structural, morphological, and physico-chemical analyses. The $MnO_x/TiO_2$ were prepared from three different precursors such as manganese nitrate, manganese acetate (II), and manganese acetate (III) by the sol-gel method and then it calcinated at $500^{\circ}C$ for 2 hr. The structural analysis was carried out to identify the phase transition and the change intensity of catalytic activity by various manganese precursors was analyzed by FT-IR and Raman spectroscopy. These different precursors also led to various surface Mn concentrations indicated by SEM. The Mn acetate (III) tends to be more suppressive the crystalline phase (rutile), and it has not only smaller particle size, but also better distributed than the others. It was confirmed that the catalytic activity of MA (III)-$MnO_x/TiO_2$ was the highest among them.