• Bulletin of the Korean Chemical Society
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• 제34권4호
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• pp.1021-1022
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• 2013

• 멤브레인
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• 제33권4호
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• pp.233-233
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• 2023

• 멤브레인
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• 제30권4호
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• pp.242-251
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• 2020

고분자 소재 및 이를 이용하여 제조된 분리막에 주로 활용되는 전산모사 도구들은 모사대상의 크기 및 모사하고자 하는 시간에 따라 여러 가지 분야로 나뉘어진다. 본 총설에 소개되는 전산모사는 그 중에서 전산재료화학에 주로 사용되는 양자역학(quantum mechanics; QM), 분자동역학(molecular dynamics; MD), 메조스케일 전산모사(mesoscale modelling), 이렇게 3가지로 분류된다. 고분자 연구에서 사용되는 전산모사는 각각의 전산모사의 종류마다 연구내용이 달라지는데, 양자역학은 분자, 원자, 전자 등 미시적인 계의 현상을 다루어 작은 크기의 현상을 연구하고, 분자동역학은 원자들 사이의 퍼텐셜 또는 힘이 주어졌을 때 뉴턴의 운동방정식에 따른 원지 및 분자의 움직임을 수치적으로 풀어내고, 메조스케일 모델링은 원자들을 묶어서 그룹형태로 만들어 비드를 형성해 비교적 큰 분자량에서 계산시간을 줄여 거시적으로 판단하는 연구가 된다. 본 총설에서는 고분자 및 고분자 분리막에 주로 활용되는 다양한 전산모사 프로그램을 위에서 분류한 3가지 종류로 나누어 각각의 특징과 사용분야 등을 소개하고자 한다.

• Macromolecular Research
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• 제16권7호
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• pp.590-595
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• 2008

The pressure driven membrane process has been a breakthrough in the removal of pollutants from drinking water. These experiments examined the removal of chlorophenol compounds from water using low pressure membranes. The removal performance of the membranes was based primarily on size exclusion. Apart from size exclusion, the polarity and pKa of the compounds also influences the membrane performance. The molecular size and dipole moments of the respective molecules were calculated using a quantum chemical method. The rejection of pollutants also followed the same trend as salt rejection by the membranes.

• Macromolecular Research
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• 제17권12호
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• pp.995-1002
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• 2009

Luminescent polynorbornene (PNB)/quantum dot (CdSe@ZnS; QD) composite nanorods and nanotubes were successfully prepared using anodic aluminum oxide (AAO) membranes of various pore sizes as templates. To protect QDs with high quantum yield from quenching during the phosphoric acid treatment used to remove the AAO templates, chemically stable and optically clear norbornene-maleic anhydride copolymers (P(NB-r-MA)) were employed as a capping agent for QDs. The amine-terminated QDs reacted with maleic anhydride moieties in P(NB-r-MA) to form PNB-grafted QDs. The chemical- and photo-stability of QDs encapsulated with PNB copolymers were investigated by photoluminescence (PL) spectroscopy. By varying the pore size of the AAO templates from 40 to 380 urn, PNB/QD composite nanorods or nanotubes were obtained with a good dispersion of QDs in the PNB matrix.

• 멤브레인
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• 제30권5호
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• pp.293-306
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• 2020

물 부족을 포함한 기후 변화의 해로운 결과는 효과적인 정수에 대한 관심을 가져왔다. 또한, 수질 오염 수준이 높아지고 환경 파괴 수준이 심해지면서 오염 물질을 제거하려는 방안들이 요구되고 있다. 물을 정화하기 위해 반투막을 통한 삼투압 절차들을 사용할 수 있으며, 최근 연구에 따르면 탄소 양자점(CQD), 그래핀 양자점(GQD) 및 산화 그래핀 양자점(GOQD)을 포함한 나노입자를 복합 박막(TFC)에 합체하면 유사한 수준의 염 거부율을 유지하면서 물흐름을 증가시킬 수 있다. 이러한 효과 외의 여러 가지 효과가 있지만 그 중에서도 친수성을 높이고, 살균 성질을 보이고, 방오 특성으로 인해 박테리아 및 기타 미생물의 축적을 방지하면서 막의 효과가 감소하는 것을 막는 것을 보여준다. 이 보고서는 양자점이 합체된 정수용 복합 막에서 양자점의 제조 과정, 응용, 기능성, 성질 및 역할을 논의한다.

• 한국막학회:학술대회논문집
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• 한국막학회 2003년도 The 4th Korea-Italy Workshop
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• pp.99-100
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• 2003

No Abstract, See Full Text

• Rapid Communication in Photoscience
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• 제4권2호
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• pp.45-47
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• 2015

We have successfully synthesized $AgInS_2$ core and $AgInS_2$/ZnS core/shell nanoparticles by the sonochemical method. The ultrasonic based $AgInS_2$ and $AgInS_2$/ZnS nanoparticle synthesis can be utilized as a simple and rapid method. The $AgInS_2$/ZnS nanoparticles show the higher fluorescence intensity and quantum yield than $AgInS_2$ nanoparticles. Fluorescence wavelength of $AgInS_2$/ZnS shows blue shift from 635 nm to 610 nm against $AgInS_2$ because of reducing the defect sites and increasing spatial confinements. For the fluorescence lifetime, $AgInS_2$/ZnS (124.8 ns) has longer lifetime than $AgInS_2$ (54.8 ns).

• Journal of Photoscience
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• 제1권2호
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• pp.95-105
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• 1994

Experiments were carried out to investigate whether P, deficiency in detached 25 mM mannose-feeding led to a decline of the photosynthetic electron transport rates through acidification of the thylakoid lumen. With increasing mannose-feeding time, the maximal CO2 exchange rates and the maximal quantum yields of photosynthesis decreased rapidly up to 6 h by 73% then with little decrease up to 12 h. The ATP/ADP ratio declined by 54% 6 h after the treatment and then recovered to the control level at 12 h. However, the NADPH/NADP~ ratio was not significantly altered by mannose treatment. Electron transport rates of thylakoid membranes isolated from 6 h treated leaves did not change, but they decreased by 30% in 12 h treated leaves. The quenching analysis of Chl fluorescence in mannose-treated leaves revealed that both the fraction of reduced plastoquinone and the degree of acidification of thylakoid lumen remained higher than those of the control. The reduction of PSI in mannose fed leaves was inhibited due to acidification of thylakoid lumen (high qE). The reduction of primary quinone acceptor of PSII was inhibited by mannose feeding. Mannose treatment decreased the efficiency of excitation energy capture by PSII. Fo quenching was induced when treated with mannose more than 6 h, and had a reverse linear correlation with (Fv)m/Fm ratio. These results suggest that Pi deficiency in Chinese cabbage leaves reduce photosynthetic electron transport rates by diminishing both PSII function and electron transfer from PSII to PSI through acidification ofthylakoid lumen, which in turn induce the modification of photosynthetic apparatus probably through protein (de)phosphorylation.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.347-347
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• 2006

Polymers containing poly(vinyl phosphonic) acid segments are promising candidates to be used as proton conducting membranes. Solid state NMR spectroscopy represents an ideal probe of proton motion on the molecular level, because it allows us to selectively detect the nuclei of interest. In this paper, we apply solid state NMR methods to poly(vinyl phosphonic) acid in order to demonstrate that the proton conduction of poly(vinyl phosphonic acid) results from P-OH proton through hydrogen bonding and that the condensation of phosphonic acid leads to decrease in proton conductivity. $^{1}H\;and\;^{31}P$ solid state NMR experiments are supported by quantum chemical computation of NMR parameters.