• The KSFM Journal of Fluid Machinery
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• v.10 no.5
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• pp.20-26
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• 2007

Some gate valves are susceptible to pressure locking and thermal binding which prevent the safety function. The safety related gate valves susceptible to pressure locking and thermal binding shall be identified and taken preventive actions to ensure the safety function. The identification of the gate valves susceptible to pressure locking and thermal binding needs the evaluation of system design, valve and piping arrangement, test requirements, and operating conditions. Application of preventive methods should consider the system safety function, applicability, effectiveness, interface with system design, and cost. The selection procedure of valves susceptible to pressure locking and thermal binding can be effectively used in industry including nuclear power plants. In order to prevent the pressure locking, the hole can be drilled through the one disc of upstream side or down stream and the external equalizing line can be installed from bonnet to downstream or upstream. The double disc parallel seat valve type can be used instead of flexible wedge gate valve to prevent the thermal binding. The identification of gate valves susceptible to pressure locking and thermal binding, and preventive actions will meet the regulatory requirements and enhance the availability and safety of plants.

• Journal of the Korean Chemical Society
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• v.62 no.2
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• pp.106-112
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• 2018

Ice-binding proteins have an affinity for ice. They create a gap between the melting and freezing points by inhibiting the growth of ice, known as thermal hysteresis (TH). Interestingly, moderately active LeIBP and hyperactive FfIBP are almost identical in primary and tertiary structures, but differ in TH activity. The TH of FfIBP is tenfold higher than that of LeIBP, due to a subtle difference in their ice-binding motifs. To further evaluate the difference in TH, the interactions were investigated by ice-etching and molecular docking. Ice-etching showed that FfIBP binds to the primary and secondary prism, pyramidal, and basal planes; previously, LeIBP was found to bind to the basal and primary prism planes. Docking analysis using shape complementarity (Sc) showed that the hyperactive FfIBP had higher Sc values for all four ice planes than LeIBP, which is comparable with TH. Docking can be used to describe the hyperactivity of IBPs.

• KSBB Journal
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• v.14 no.3
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• pp.273-278
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• 1999

The molecularly imprinted polymers(MIPs) synthesized at various polymerization conditions were examined as ibuprofen receptors in terms of binding characteristics. The 4-vinylpyridine polymers had 1.2 times higher adsorption capability for (S)-(+)-ibuprofen than the methacrylic acid polymers. The methacrylic acid polymers synthesized by UV radiation had 1.9 times higher selectivity for (S)-(+)-ibuprofen compared to those by thermal initiation. Effects of various solvents for binding were also examined in this research. According to the Scatchard analysis, the (S)-(+)-ibuprofen artificial receptors had two different kinds of binding sites for (S)-(+)-ibuprofen while having only single kind of binding site for ketoprofen. The binding sites of (S)-(+)-ibuprofen, n were calculated as 4.3~4.9 $\mu$mol/g and the dissociation constants, $K_D$ were 0.68 mM for the specific binding.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.131-135
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• 2005

In general, the application of HP contributes to improvement of functionalities of meat protein. In the current study, HP allowed the lower thermal processing of restructured meat product. Low thermal processing allowed fresh-like meat color which is one of problems in hot-set restructuring, while they showed slight discolorization induced by HP. In addition, HP processing combined with thermal processing could be achieved the palatable binding strength in restructured meat product. The addition of non-meat protein had an effect in binding strength. However, they showed no effect on water binding properties at 200 MPa, especially in milk proteins such as casein and whey protein. This is probably due to protein aggregation or to increase in surface hydrophobicity under HP. This result indicates that the application of HP on meat restructuring is more significant than the addition of binders. Therefore, the application of HP has apotential benefit in restructured meat product, and further investigations are needed.

• Journal of the Korean Ceramic Society
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• v.49 no.5
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• pp.412-416
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• 2012

Porous SiC ceramics were prepared by using recycled SiC sludge, which is an industrial waste generated from solar cell industry. Polycarbosilane derivatives, such as polycarbosilane (PCS), polyphenylcarbosilane (PPCS) and hydridopolycarbosilane (HPCS) were used as binding agents for the fabrication of porous SiC ceramics at $1800^{\circ}C$ under Ar atmosphere. The effects of the various binding agents having different C/Si ratios were discussed on the sintering and porosity of the SiC ceramics. The prepared porous SiC ceramics were characterized by X-ray Diffraction (XRD) and Field-Emission Scanning Electron Microscope (FE-SEM). Thermal conductivity and porosity of SiC ceramics were measured at room temperature, and they were 56.7W/mK and 29.8%, respectively.

• Journal of the Korean Magnetic Resonance Society
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• v.10 no.2
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• pp.175-187
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• 2006

Binding interactions between a positively charged porphyrin derivative TMAP(meso-tetra(p-trimethylanilinium-4-yl)porphyrin) and triple helical $(dT)_{12}{\cdot}(dA)_{12}{\cdot}(dT)_{12}$, as well as double helical $(dA)_{12}{\cdot}(dT)_{12}$ have been studied with NMR, UV and CD spectroscopy to obtain the detailed information about the binding mode and binding site. UV melting studies showed both DNA duplex and triple helix represented very similar UV absorption patterns upon binding TMAP, but the presence of third strand of triple helical $(dT)_{12}{\cdot}(dA)_{12}{\cdot}(dT)_{12}$, inhibited improvement in thermal stability in terms of melting temperature, $T_m$. In addition, the TMAP molecule is thought to bind to the major groove, according to CD and NMR data. But absence of the clear isosbestic point in UV absorption spectra represented that binding of TMAP to DNA duplex as well as DNA triplex did not show a single binding mode, rather complex binding modes.

• Journal of the Korean Magnetic Resonance Society
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• v.18 no.2
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• pp.52-57
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• 2014

The TCP domain is a DNA-binding domain present in plant transcription factors and plays important roles in various biological functions. The hydrogen exchange rate constants of the imino protons were determined for the three DNA duplexes containing the DNA-binding sites for the TCP11, TCP15, and TCP20 transcription factors using NMR spectroscopy. The M11 duplex displays unique hydrogen exchange property of the five base pairs in the first binding site (5'-GTGGG-3'). However, the M15 and M20 duplexes lead to clear changes in thermal stabilities of these five base pairs. The unique dynamic features of the five base pairs in the first binding site might play crucial roles in the sequence-specific DNA binding of the class I TCP transcription factors.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.185-188
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• 2000

The dissociation of excitons bounds to neutral accepter in CdTe single crystal was investigated by measurement of temperature dependence of the photoluminescence spectra. The binding energies of CdTe single crystal were determined by PL spectrum at 12K. The free exciton (X) binding energy, the exciton binding energy on neutral donor ($D^{\circ}$, X), and the exciton binding energy on neutral acceptor ($A^{\circ}$, X) were 10 meV, 3.49 meV, and 7.17 meV respectively. From the value of activation energy of ($A^{\circ}$, X), we could show that the dissociation of ($A^{\circ}$, X) is attributed to free exciton.

• Bulletin of the Korean Chemical Society
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• v.30 no.9
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• pp.1973-1977
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• 2009

In the present study, at first, 2,4-Dihydroxy Salophen (2,4-DHS), has been synthesized by combination of 1, 2-diaminobenzene and 2,4-dihydroxybenzaldehyde in a solvent system. This ligand containing meta-quinone functional groups were characterized using UV-Vis and IR spectroscopies. Subsequently, the interaction between native calf thymus deoxyribonucleic acid (ct-DNA) and 2,4-DHS, was investigated in 10 mM Tris/HCl buffer solution, pH 7.2, using UV-visible absorption and fluorescence spectroscopies, thermal denaturation technique and viscosity measurements. From spectrophotometric titration experiments, the binding constant of 2,4-DHS with ct-DNA was found to be (1.1 ${\pm}\;0.2)\;{\times}\;10^4\;M^{-1}.$ The fluorescence study represents the quenching effect of 2,4-DHS on bound ethidium bromide to DNA. The quenching process obeys linear Stern-Volmer equation in extended range of 2,4-DHS concentration. Thermal denaturation experiments represent the increasing of melting temperature of DNA (about 3.5 ${^{\circ}C}$) due to binding of 2,4-DHS. These results are consistent with a binding mode dominated by interactions with the groove of ct-DNA.

• Nuclear Engineering and Technology
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• v.43 no.3
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• pp.257-270
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• 2011

A set of reflood tests has been performed using ATLAS, which is a thermal-hydraulic integral effect test facility for the pressurized water reactors of APR1400 and OPR1000. Several important phenomena were observed during the ATLAS LBLOCA reflood tests, including core quenching, down-comer boiling, ECC bypass, and steam binding. The present paper discusses those four topics based on the LB-CL-11 test, which is a best-estimate simulation of the LBLOCA reflood phase for APR1400 using ATLAS. Both homogeneous bottom quenching and inhomogeneous top quenching were observed for a uniform radial power profile during the LB-CL-11 test. From the observation of the down-comer boiling phenomena during the LB-CL-11 test, it was found that the measured void fraction in the lower down-comer region was relatively smaller than that estimated from the RELAP5 code, which predicted an unrealistically higher void generation and magnified the downcomer boiling effect for APR1400. The direct ECC bypass was the dominant ECC bypass mechanism throughout the test even though sweep-out occurred during the earlier period. The ECC bypass fractions were between 0.2 and 0.6 during the later test period. The steam binding phenomena was observed, and its effect on the collapsed water levels of the core and down-comer was discussed.