• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4281-4285
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• 2011

We introduced a promising patterned substrate by using a microcontact printing method that can be used for SERS immunoassays based on antigen-antibody binding. SERS spectrum of the Raman reporter with antibody, which is rhodamine 6G (R6G) adsorbed on colloidal gold nanoparticles, was observed only for the surfaces in which prostate-specific antigen (PSA) is present on the substrate that is attached to an immobilized layer of antibody on the gold nanoparticles layer of the patterned substrate. Raman mapping images clearly showed that the antibodies on the Raman reporter were successfully and selectively conjugated with the antigen on the patterned substrate. This method could be potentially extended to multi-protein detections and ultrasensitive biosensors.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.607-609
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• 2009

We present a Brownian molecular dynamics computer simulation method for calculating the rotational viscosity of the liquid crystal mixture comprising pentylcyanobiphenol (5CB) and decylcyanobiphenol (10CB). Mean director of the ensemble has been used as a nematic director. Results show a good agreement with experimental ones [Sudeshna DasGupta et al., Physics Letters A 306(2003)235-242].

• Bulletin of the Korean Chemical Society
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• v.25 no.11
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• pp.1657-1660
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• 2004

Several critical geometries associated with the rearrangement of $CH_3SNO_2\;to\;CH_3SONO$ are calculated with the density functional theory (DFT) method and compared with those of the ab initio molecular orbital methods. There are two probable pathways for this rearrangement, one involving the transition state of an oxygen migration and the other through the homolytic decomposition to radicals. The reaction barrier via the transition state is about 60 kcal/mol and the decomposition energy into radicals about 35 kcal/mol, suggesting that the reaction pathway via the homolytic cleavage to radical species is energetically favorable. Since even the homolytic cleavage requires large energies, the rearrangement reaction is unlikely without the aid of catalysts.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.610-612
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• 1999

In this study, we used both displacement-current method and BAM(Brewster-Angle Microscope) to study on the molecular orientation of monolayer on the water surface. The displacement-current method measured behaviors of molecules by current and BAM was shown to be sensitive to film anisotropy even when the molecules were not tilted as long as the unit cell was anisotropic. Every transition was visible with BAM technique, either as a dramatic change in decree of contrast or as a sudden alteration of the mosaic domain texture.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.3
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• pp.24-28
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• 2001

The utilization of wastepaper as a papermaking raw material is everlastingly required for the environmental protection of earth. However the recycling of wastepaper for this purpose cause another problem such as the increasing of the load of wastewater treatment, lower strength properties of paper, and poor printability, etc. The interest in the development of the environmentally friendly deinking technology is increased continuously. Thus, our research team have tried to apply the ozone to the deinking of white ledger and ONP, and obtained the positive results which can be considered as an alternative method for the conventional deinking method. The purpose of this study is to investigate the mechanism of ozone deinking. Styrene acrylate and polystyrene were treated with ozone and measured the change of molecular weight with the GPC. The molecular weight distribution obtained with GPC showed only slight increase by the ozone treatment, and gel formation by the polymerization was observed. Therefore the removal of ink particles with ozone treatment seems to be facilitated by the increase of the brittleness and decrease of adhesive property.

• Bulletin of the Korean Chemical Society
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• v.15 no.3
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• pp.241-245
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• 1994

A method has been developed to estimate the kinetic energy release originating from the reverse critical energy in unimolecular ion dissociation. Contribution from the excess energy was estimated by RRKM theory, the statistical adiabatic model and the modified phase space calculation. This was subtracted from the experimental kinetic energy release distribution (KERD) via deconvolution. The present method has been applied to the KERDs in $H_2$, loss from $C_6H_6^+$ and HF loss from ${CH_2CF_2}^+$. In the present formalism, not only the energy in the reaction coordinate but also the energy in some transitional vibrational degrees of freedom at the transition state is thought to contribute to the experimental kinetic energy release. Details of the methods for treating the transitional modes are found not to be critical to the final outcome. For a reaction with small excess energy and large reverse critical energy. KERD is shown to be mainly governed by the reverse critical energy.

• Current Applied Physics
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• v.18 no.12
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• pp.1528-1533
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• 2018

The trajectories of adsorption and dissociation process of $O_2$ on the Al (111) surface were studied by the spinpolarized ab initio molecular dynamics method, and the adsorption activation energy was clarified by the NEB method with hybrid functionals. Three typical dissociation trajectories were found through simulation of $O_2$ molecule at different initial positions. When vertically approaches to the Al surface, the $O_2$ molecule tends to rotate, and the activation energy is 0.66eV. If $O_2$ molecule does not rotate, the activation energy will increase to 1.43 eV, and it makes the O atom enter the Al sublayer eventually. When the $O_2$ molecules parallel approach to the Al surface, there is no activation energy, due to the huge energy released during the adsorption process.

• Korean Journal of Clinical Laboratory Science
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• v.44 no.3
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• pp.155-165
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• 2012

The purpose of this study was to develop a multiplex PCR for the detection of aac(6')-Ib, aph(3')-Ia, and ant(2")-Ia; the genes that encode the most clinically relevant aminoglycoside modifying enzymes (AMEs) in Gram-negative bacteria. Clinical isolates of 80 E. coli and 23 K. pneumoniae from tertiary university hospital were tested by multiplex PCR. The most prevalent AME gene was aac(6')-Ib which was found in 22.3% of the isolates. Of the total 80 E. coli isolates, 1 isolate was found to contain both aph(3')-Ia and ant(2")-Ia simultaneouly. Of the total 23 K. pneumoniae isolates, 2 isolates were found to contain both aac(6')-Ib and aph(3')-Ia, and 1 isolate was found to contain both aac(6')-Ib and ant(2")-Ia simultaneously. Annual (2005~2009) analysis of isolates that contain the AME genes were of no correlation. The sensitivity and specificity of multiplex PCR in detecting AME genes was 94.4% (34 of 36 cases) and 100%, respectively. We suggest the multiplex PCR method we developed could be highly sensitive and specific in detecting the AME genes of E. coli and K. pneumoniae. This study could be the first published investigation in which the multiplex PCR method detects aac(6')-Ib, aph(3')-Ia, and ant(2")-Ia genes.

• Journal of Microbiology and Biotechnology
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• v.17 no.5
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• pp.806-811
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• 2007

Bacillus anthracis is a soil pathogen capable of causing anthrax that is closely related to several environmental species, including B. cereus, B. mycoides, and B. thuringiensis. DNA homology studies showed that B. anthracis, B. cereus, B. mycoides, and B. thuringiensis are closely related, with a high sequence homology. To establish a method to specifically detect B. anthracis in situations such as environmental contamination, we initially performed RAPD-PCR with a 10-mer random primer and confirmed the presence of specific PCR bands only in B. anthracis species. One region specific for B. anthracis was cloned and sequenced, and an internal primer set was designed to amplify a 241-bp DNA fragment within the sequenced region. The PCR system involving these specific primer sets has practical applications. Using lyses methods to prepare the samples for PCR, it was possible to quickly amplify the 241-bp DNA segment from samples containing only a few bacteria. Thus, the PCR detection method developed in this study is expected to facilitate the monitoring of environmental B. anthracis contamination.

• Journal of the Korea Convergence Society
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• v.10 no.3
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• pp.23-30
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• 2019

The purpose of this study is to find out the structure of the substance that affects antidiabetic using the candidate drug information for diabetes treatment. A quantitative structure activity relationship model based on machine learning method was constructed and major molecular descriptors were determined for each experimental data variables from coefficient values using a partial least squares algorithm. The results of the analysis of the molecular access system fingerprint data reflecting the candidate drug structure information were higher than those of the in vitro data analysis in terms of goodness-of-fit, and the major molecular expression factors affecting the antidiabetic effect were also variously derived. If the proposed method is applied to the new drug development environment, it is possible to reduce the cost for conducting candidate screening experiment and to shorten the search time for new drug development.