• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2927-2929
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• 2009

The hydricities of d$^6$ metal hydride complexes in aqueous solution were calculated by using density functional theoretical (DFT) calculations coupled with a Poisson-Boltzmann (PB) solvent model. Hydricity describes the hydride donor ability of the metal-hydrogen bond, which assists in the study of the mechanism of many catalytic processes and chemical reactions that involve transition metal hydrides. The calculation scheme produced hydricity values that were in good agreement with experimental estimation. The inclusion of a water molecule as a weakly bound ligand to five-coordinate metal complexes gave an improved correlation result.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.5
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• pp.179-184
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• 2006

In a power system, an out-of-step condition causes a variety of risk such as serious damage to system elements, tripping of loads and generators, mal-operation of relays, etc. Therefore, it is very important to detect the out-of- step condition and take a proper measure. This paper presents a study on implementation of out-of-step detection algorithm using VHDL(Very high speed Hardware Description Language). The structure of out-of-step detection algorithm is analyzed for development of out-of-step detection relay on the FPGA(Field Programmable Gate Array). The out-of-step algorithm is separated to 4 parts: DFT IP, complex power calculation IP, out-of-step detection IP, control unit. Each parts are developed and simulated by using VHDL.

• Proceeding of EDISON Challenge
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• 2013.04a
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• pp.273-277
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• 2013

We apply a density functional theory (DFT) and DFT-based non-equilibrium Green's function approach to study the electronic and transport properties of graphene nanoribbons (GNRs) co-doped with boron-nitrogen, nitrogen-phosphorus and boron-phosphorus. We analyze the structures and charge transport properties of co-doped GNRs and particularly focus on the novel effects that are absent for the single N-, B-, or P-doped GNRs. It is found that co-doped GNRs tend to be doped at the edges and the electronic structures of co-doped GNRs are very sensitive to the doping sites. Also, in case of B-N and B-P co-doped GNRs, conductance dips of single-doped GNRs disappeared with the disappearance of localized states associated with doped atoms. This may lead to a possible method of band engineering of GNRs and benefit the design of graphene electronic devices.

• Journal of Integrative Natural Science
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• v.15 no.4
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• pp.153-161
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• 2022

c-Jun N-terminal kinases (JNKs) are members of MAPK family. Many genes can relay signals that promote inflammation, cell proliferation, or cell death which causes several diseases have been associated to mutations in the JNK gene family. The JNK2 gene is significantly more important in cancer development than the JNK1 and JNK3 genes. There are several different ways in which JNK2 contributes to breast cancer, and one of these is through its role in cell migration. As a result, this study's primary objective was to employ computational strategies to identify promising leads that potentially target the JNK2 protein in a strategy to alleviate breast cancer. We have derived these anticancer compounds from marine brown seaweed called Turbinaria conoides. We have identified compounds Ethane, 1, 1-diethoxy- and Butane, 2-ethoxy as promising anti-cancer drugs by molecular docking, DFT, and ADME study.

• Corrosion Science and Technology
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• v.21 no.1
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• pp.21-31
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• 2022

Potentiodynamic polarization, EIS measurements, quantum chemical calculations, and molecular dynamic simulations were used to investigate the corrosion behavior of mild steel in 0.5 M aqueous hydrochloric acid medium in the presence or absence of nystatin drug. Potentiodynamic tests suggested that this molecule could act as a mixed inhibitor due to its adsorption on the mild steel surface. The objective of this study was to exploit theoretical calculations to gain a better understanding mechanism of inhibition. Calculating the adsorption behavior of the investigated molecule on Fe (1 1 0) surface was accomplished using Monte Carlo simulation. Molecules were also investigated using Density Functional Theory (DFT), specifically PBE functional, in order to identify the link between molecular structure and corrosion inhibition behavior of the compound under investigation. Adsorption energies between nystatin and iron were estimated more accurately by utilizing Molecular Mechanics calculation with Periodic Boundary Conditions (PBC). Estimated theoretical parameters significantly assisted our understanding of the corrosion inhibition mechanism exhibited by this molecule. They were found to be in accord with experimental results.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.246-261
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• 2023

We investigated critical temperature for early marginal transplanting (CT-EMT) of the contemporary japonica rice varieties in Korea through the field, pot seedling tray, and the phytotron experiments during 2020 to 2023. The lowest mean temperature for 10 days from transplanting (MT-10DFT) that resulted in earlier heading date was 12.4℃ and the highest MT-10DFT that did not show the earlier heading date was 12.0℃ in the field study when the MT-10DFT varied by changing transplanting date. The lowest MT-10DFT that induced the increased biomass but not the earlier heading date was 11.6℃ and the highest MT-10DFT that showed neither the increased biomass nor the earlier heading date was 11.4℃. Compared to the 10-day later transplanting, the dates of the first root development, initiation of the chlorophyll recovery, and the first tiller development were earlier when the MT-10DFT was 9.1℃ or higher, 10.5℃ or higher, and 11.6℃ or higher, respectively, in the pot seedling tray and field experiments. The earliness of the first tiller development was a practical index for the estimation of CT-EMT during the early growth stage of rice. The response of transplanted rice to temperature treatments with the diurnal change of 10℃ in the phytotron study was similar to that shown in the field study. The data shown for constant temperature without a diurnal change revealed that the extent of positive effects of high temperature at day-time was greater than the extent of negative effects of low temperature at night-time on the early growth of transplanted rice. It was concluded that the critical MT-10DFT for early marginal transplanting of japonica rice in the temperate environments was between 11.4 to 11.6℃ based on the plant growth and between 12.0 to 12.4℃ based on the plant development.

• Journal of the Korean Chemical Society
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• v.59 no.6
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• pp.541-544
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• 2015

• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.1202-1204
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• 2014

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.05a
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• pp.407-408
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• 2018

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.3
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• pp.576-582
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• 1998

The purpose of the study was to determine the ability of the caries activity test, 'Cariostat' to identify preschool children with dental caries. The subjects of this study were 76 children of 3 to 5 years of age. Oral examination was carried out to assess the caries experience using a mirror and explorer. In all subjects buccal plaque samples were obtained, incubated, and scored as the manufacturer's instructions for the Cariostat test. Statistical analyses were used with the Crosstabulation. The test group exhibited mean dft index 5.21, while 27.63% of subjects were caries free and had no restorations. The sensitivity of the Cariostat test was found to be 98.8% while the specificity was found to be 19.05% The results showed that caries activity measured by visual reading was highly significant to the Cariostat score and dft index(P<0.001). The Cariostat method has indicated the future possible occurrence of caries. The use of this method is meant to require in the caries prevention program.