• Journal of the Korean Chemical Society
• /
• v.22 no.1
• /
• pp.1-6
• /
• 1978

Feeling the potential field within a cell for various environments, every liquid molecule moves to minimize its potential energy. With this simple and fundamental concept, liquid molecules may be treated as a combination of three kinds of typical molecules characterized by Lennard-Jones and Devonshire's earlier work. We can get a partition function which has better functional from and less defects compared to the cell theory and the significant structure theory.

• Prospectives of Industrial Chemistry
• /
• v.22 no.4
• /
• pp.13-19
• /
• 2019

최근 가공할만한 성능의 슈퍼컴퓨터에 머신 러닝 기법을 연동한 인공 지능형 소재 정보학이 과학 기술 및 산업계에 새로운 연구개발 패러다임으로 급속히 확산되고 있다. 본 기고문에서는 이 기법의 성공에 핵심적 요소인 정확한 데이터베이스 구축을 위해 제일원리 전산을 적용하는 것과 이를 기반으로 소재를 구성하는 원소 간 인공 신경망 포텐셜을 만드는 방법을 소개하고자 한다. 이 연구 방법론은 나노 스케일 신소재 개발에 적용할 경우, 양자역학 수준의 정밀도로 순수 제일원리 전산 대비 100배 이상의 빠른 결과를 도출할 가능성이 있음을 예시한다. 이는 향후 다양한 산업계에 막대한 파급효과를 가져올 것으로 예상된다.

• Journal of the Korean Chemical Society
• /
• v.20 no.2
• /
• pp.97-110
• /
• 1976

Effects of direct multiple quantum excitations in vibrational energy transfer were investigated. Vibrational transition probabilities for 0${\rightarrow}$2, 0${\rightarrow}$3, and 0${\rightarrow}$4 excitations were explicitly formulated including both direct 0→n excitations and stepwise single quantum processes. For the formulation the perturbing force was derived from the exponential potential including terms up to fourth order in the vibrational amplitude. The head-on collinear collision model between a harmonic oscillator and an incident particle was employed, and the formulation was based on the semiclassical approximation. Numerical results were obtained for five different collision systems (Ar${\cdots}$O-N, He${\cdots}$H-H, He${\cdots}$H-Cl, 5${\cdots}$1-2, 2${\cdots}$12-12). Comparison between the present results and those obtained using the linearized interaction potential showed that the overall effect of including the direct multiple quantum transition is to decrease the probabilities at low collision energies and to increase them at high energies. The present results were found to be significantly different from those obtained using the linearized potential for collision systems He${\cdots}$H-H, He${\cdots}$H-Cl, and 5${\cdots}$1-2. For systems Ar${\cdots}$O-N and 2${\cdots}$12-12 the differences were negligible.

• Journal of the Korean Chemical Society
• /
• v.19 no.5
• /
• pp.294-303
• /
• 1975

An idealized linear collision model has been employed to calculate the reaction probabilities for the three-atom rearrangement reaction $A+B-C{\to}A-B+C$. Potential energy surface used is also a highly idealized one with constant values. Numerical results were obtained for the system in which the atomic masses of all three atoms are the same. Potentials were varied to see the effect of the magnitude of the opposing potential barrier on the reaction probabilities. Results obtained were compared with those obtained using different models.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2010.02a
• /
• pp.371-371
• /
• 2010

탄소나노튜브(CNT)는 기계적인 특성이 뛰어나며, 화학적으로 안정하고, 전기적으로 도체 및 반도체성을 가지고 있을 뿐만이 아니라 직경이 최소 1nm 수준으로 종횡비 및 비표면적이 매우 큰 특성을 가지고 있다. CNT는 투명전극, 유연성 디스플레이, 전자종이 분야 등 투명 전극 응용 분야에서 ITO 대체 신소재로 각광을 받고 있다. 본 발표에서는 SWCNT 전도막의 특성을 향상시키기 위해 PET 기판에 다양한 전처리 방법을 적용하여 SWCNT의 부착력 및 접착력, 투명전극의 면저항, 투과도 및 균일도 향상을 통해 SWCNT 투명전극 특성향상 연구를 진행했다. 접촉각과 표면에너지 제어를 통한 박막특성과의 상관관계 분석, 전처리 방법에 따른 표면에너지 및 제타포텐셜 변화와 박막특성과의 관계를 규명, Roughness 조절을 통한 기판의 면저항과 투과도 향상, 플라즈마 및 polymer 처리를 통해 물리적, 화학적 기판 전처리에 따른 SWCNT 투명전극 특성 향상을 목적으로 실험을 진행했다. 플라즈마 처리 후 polymer 처리된 박막에서는 친,소수 작용기 양의 변화에 따른 상관관계를 보이지 않았지만, 플리즈마 처리 후 친,소수 작용기 양과 Roughness 변화정도에 대해서는 면저항과 투과도의 변화를 보였다.

• Korean Chemical Engineering Research
• /
• v.51 no.2
• /
• pp.233-239
• /
• 2013

A quartz crystal microbalance (QCM) system coated with poly (isobutylene), polystyrene, and poly (methyl methacrylate) has been prepared to measure the adsorption amounts of benzene, toluene, and p-xylene at very low pressures. The resonant frequency shift of the QCM system is proportional to the increase in pressure in all experiments. The Henry's constants for all adsorbates on the polymer films are obtained from experimental data and compared with the minimum adsorption potential energies between adsorbates and the polymer films. In general, there is an explicit correlation between adsorption amount and the minimum adsorption potential energy.

• The Journal of the Convergence on Culture Technology
• /
• v.4 no.4
• /
• pp.343-348
• /
• 2018

Anthocyanin derivatives are an important of natural compounds responsible for the red, purple and blue colors in a large number of plants. This molecules are polymethoxy-derivatives of 2-phenylbenzopyrylium salts. Despite the beneficial properties of anthocyanins, the effectiveness of preventing or treating various diseases depends on bioavailability. Therefore, In this study, in order to investigate the electrical characteristics of anthocyanin derivatives, we investigated the electrochemical properties of derivatives by calculating the total energy, bandgap, net charge of anthocyanin derivatives using HyperChem8.0's PM3 method.

• 한국신재생에너지학회:학술대회논문집
• /
• 2007.11a
• /
• pp.585-589
• /
• 2007

Gas hydrate is a special kind of inclusion compound that can be formed by capturing gas molecules to water lattice in high pressure and low temperature conditions. When referred to standard conditions, $1m^3$ solid hydrates contain up to $172Nm^3$ of methane gas, depending on the pressure and temperature of production, Such large volumes make natural gas hydrates can be used to store and transport natural gas. In this study, three-phase equilibrium conditions for forming methane hydrate were theoretically obtained in aqueous single electrolyte solution containing 3wt% Nacl. The results show that Nacl acts as a inhibitor, but help gases such as ethan, propane, i-butane, and n-butane reduce the hydrate formation pressure at the same temperature.

• Journal of the Korean Solar Energy Society
• /
• v.27 no.4
• /
• pp.51-58
• /
• 2007

Gas hydrate is a special kind of inclusion compound that can be formed by capturing gas molecules to water lattice in high pressure and low temperature conditions. When referred to standard conditions, $1m^3$ solid hydrates contain up to $172Nm^3$ of methane gas, depending on the pressure and temperature of production. Such large volumes make natural gas hydrates can be used to store and transport natural gas. In this study, three-phase equilibrium conditions for forming methane hydrate were theoretically obtained in aqueous single electrolyte solution containing 3wt% NaCl. The results show that the predictions match the previous experimental values very well, and it was found that NaCl acts as an inhibitor.

• Journal of the Korean Chemical Society
• /
• v.28 no.3
• /
• pp.170-175
• /
• 1984

The transport rates of $H^+$ ion by DBC and DCC as carrier molecules through organic liquid membranes were determined at 25$^{\circ}$C. The transport rates depend highly on the dielectric constants of membrane solvents and these results were discussed in terms of Born's potential energy barrier methods. The sizes of anions also affect the transport rates and these results were well explained theoreticlly by extended Born's equation.