• Bulletin of the Korean Chemical Society
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• v.9 no.6
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• pp.382-384
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• 1988

The explicit form of time correlation function between fluctuating concentrations is obtained for the model of metabolic system with negative feedback near a stable(or marginally stable) steady state.

• Bulletin of the Korean Chemical Society
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• v.13 no.2
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• pp.135-139
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• 1992

The mono(aryl)cyanoplatinum(II) complex $[Pt(CN)(C_6H_3{CH_2NMe_2}_2-26)]$, reacts with the dihalogens to yield the mono(aryl)cyanoplatinum complexes $[PtX_2(CN)(C_6H_3{CH_2NMe_2}_2-26)]$, (X = Cl, Br, I). The structural configuration of the two halogen atoms for a square planar platinum complex was studied by 1H-NMR spectroscopy and led to a mixture of trans and cis orientation. The trans orientation was found to be more stable in energy (1.33 kcal/mol) than the cis orientation by means of Extended H ckel calculations. On the base of a combination of the analysis of $^1H-NMR$, $^{13}C-NMR spectra and computational calculations it is assumed that the intermediate consists of an initial attack in the linear transition state, leading to the $S_{N}2$ type mechanism.

• Journal of Engineering Education Research
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• v.21 no.4
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• pp.53-62
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• 2018

The purpose of this study is to investigate the current conditions of the domestic and foreign curricula in the field of chemical engineering and to draw implications. The results of the study are as follows. Most of the domestic research universities (including non-certified universities) have curricula organized within the scope of the ABEEK certification, which is the minimum standard guide for chemical engineering curricula. However, we are concerned that chemical engineering education in some domestic universities may lack in education quality and program relevance. Graduates from these universities may not have equivalent qualifications as international graduates. It is considered that most of the 12 domestic universities organize their subjects according to the certificate of accreditation standard and to the traditional subjects of chemistry in the 'Department of Chemical Engineering' or 'Department of Chemical and Biological Engineering Chemical and Biological Engineering'. However, due to the increase in the number of overlapping subjects with other majors because of the movement towards academic diversity, the integrity of the chemical engineering curricula is at risk. In addition, after surveying the major and research areas of the department professors, it has been found that there is a shortage of professors who have majored in chemical engineering. Therefore, there is a concern that students may lack understanding of the core principles of chemical engineering. The results of the analysis of the curricula of overseas research universities (including non-certified universities) are as follows. Although the chemical engineering industry in developed countries like the United States and Europe is advancing and changing very quickly, the chemical engineering education in these countries is highly focused on traditional subjects and other related subjects in order to cultivate traditionally trained chemical engineers. The Department of Chemical Engineering at overseas universities still maintains the academic integrity of the chemical engineering field. This is a significant suggestion for our country. On the other hand, domestic universities are changing the name of their chemical engineering major, or even if the name is maintained, they are fusing their curriculum with other majors such as material engineering. Therefore, it is very necessary at this point to start a discussion regarding the integrity of the department of chemical engineering in Korea. We hope that the departments of chemical engineering in domestic universities maintain the integrity of traditional chemical engineering while operating the curriculum within the scope of the standards of the engineering education certification system.

• Bulletin of the Korean Chemical Society
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• v.7 no.4
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• pp.317-318
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• 1986

• Bulletin of the Korean Chemical Society
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• v.15 no.12
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• pp.1122-1124
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• 1994

• Elastomers and Composites
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• v.52 no.1
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• pp.22-26
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• 2017

The thermal conductivity and the adhesive properties were measured, after synthesis of thermal conductive composite which was obtained as a result of mixing alumina or graphite with acrylic adhesive synthesized by UV polymerization. The adhesive properties of the composite were evaluated measuring the peel strength at 180 degrees, the retention, and the initial tack;the thermal conductivity was estimated using laser flash analysis. As the filler contents increased, a decrease in peel strength and initial tack and an increase in retention and thermal conductivity were observed. When compared to alumina, the adhesion of graphite showed a dramatic decrease, whereas the thermal conductivity was further enhanced. It was found out that the small size of graphite increased the mechanical interlocking between the polymer and the filler, and it was easier for graphite to come into contact with other graphite in the matrix.

• Bulletin of the Korean Chemical Society
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• v.15 no.4
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• pp.280-284
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• 1994

• Journal of Powder Materials
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• v.25 no.1
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• pp.7-11
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• 2018

In this study, we synthesize tungsten oxide thin films by electrodeposition and characterize their electrochromic properties. Depending on the deposition modes, compact and porous tungsten oxide films are fabricated on a transparent indium tin oxide (ITO) substrate. The morphology and crystal structure of the electrodeposited tungsten oxide thin films are investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). X-ray photoelectron spectroscopy is employed to verify the chemical composition and the oxidation state of the films. Compared to the compact tungsten oxides, the porous films show superior electrochemical activities with higher reversibility during electrochemical reactions. Furthermore, they exhibit very high color contrast (97.0%) and switching speed (3.1 and 3.2 s). The outstanding electrochromic performances of the porous tungsten oxide thin films are mainly attributed to the porous structure, which facilitates ion intercalation/deintercalation during electrochemical reactions.

• Journal of the Korean Chemical Society
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• v.37 no.2
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• pp.265-268
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• 1993

• Journal of the Semiconductor & Display Technology
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• v.10 no.1
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• pp.51-55
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• 2011

The surface passivation is one of the important methods that can improve the efficiency of solar cells and can be classified into two methods: wet-chemical passivation and film passivation. In this paper, chemical HF treatment were employed for the passivation of n-type silicon wafers and their effects were studied. To investigate film passivation effects, the silicon nitride films were also deposited by PECVD (plasma-enhanced chemical vapor deposition) on n-type silicon wafers treated with chemical HF. The minority carrier lifetime measurements were used for evaluation of the passivation characteristics in the all experiments steps. We confirmed that the minority carrier lifetime was improved with chemical HF treatment due to passivation effects by H-termination.