• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.198-201
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• 2012

The electrolytes in thermal batteries are nonconductive solids at ambient temperature, which prevent the self-discharge and corrosion. To meet severe environmental requirements and guarantee acceptable handling yields, all the pellets in cells should have adequate strength, especially for the cathodes due to their poor binding properties among FeS2 particles. By modifying the surface microstructure of FeS2 through molten-salt heat treatment, the inter-particle binding strength is greatly increased, resulting in the enhanced pellet strength and yield. The addition of Li2O also promoted the soft salt coating coverage of hard FeS2 particles, which can be explained by the enhanced wettability of the molten salt.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.134.2-134
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• 2002

• Journal of Life Science
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• v.13 no.5
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• pp.751-755
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• 2003

Cyclic AMP receptor proteins(CRP) activate many genes in Escherichia coli by binding of cAMP with not fully known mechanism. CRP existed as apo-CRP in the absence of cAMP, $CRP;(cAMP)_2$$_2$ at low(micromolar) cAMP concentration, or $CRP;(cAMP)_4$ at high(millimolar) concentration of cAMP. This study is designed to measure the thermal stability of S83G CRP, which substituted glycine for serine at amino acid 83 position, with CD spectrapolarimeter at 222nm by the constant elevation of temperature from $20^{\circ]C\; to\; 90^{\circ}C\; at\; 1^{\circ}C/min$. The non-linear regression analysis showed that melting temperatures were 68.4, 72.0, and $82.3^{\circ}C$ for no cAMP, 0.1mM cAMP, and 5mM cAMP, respectively. Result showed the strong thermal stability of CRP by binding of additional cAMP molecules to region between the hinge region and helix-turn-helix(HTH) motif at 5mM cAMP concentration.

• Journal of the Korean Magnetic Resonance Society
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• v.24 no.4
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• pp.117-122
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• 2020

Transcription factors are proteins that bind specific sites or elements in regulatory regions of DNA, known as promoters or enhancers, where they control the transcription or expression of target genes. MEIS1 protein is a DNA-binding domain present in human transcription factors and plays important roles in various biological functions. The hydrogen exchange rate constants of the imino protons were determined for the wild-type containing the consensus DNA-binding site for the MEIS1 and those of the mutant DNA duplexes using NMR spectroscopy. The G2A-, A3G- and C4T-mutant DNA duplexes lead to clear changes in thermal stabilities of these four consensus base pairs. These unique dynamic features of the four base pairs in the consensus 5'-TGAC-3' sequence might play crucial roles in the effective DNA binding of the MEIS1 protein.

• Journal of Life Science
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• v.22 no.7
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• pp.863-870
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• 2012

Rhodopsin, a dim light photoreceptor, has been regarded as one of the model systems for the structural and functional study of G protein-coupled receptors (GPCRs). Constitutively active mutant GPCRs leading to the activation of heterotrimeric GDP/GTP-binding protein signaling in the absence of ligand binding are of interest for the study of the activation mechanism in GPCRs. The present study focused on the opsin mutant E134Q/M257Y, which showed a moderate level of constitutive activity and the formation of two distinct rhodopsin chromophores with absorption maxima of 500 nm and 380 nm, depending on the presence of an inverse agonist, 11-cis-retinal, and an agonist, all-trans-retinal, respectively. Reconstitution of the mutant rhodopsin upon incubation with different ratios of 11-cis-retinal and the all-trans-retinal, as well as upon sequential binding of the two retinals, indicated its preferential binding to 11-cis-retinal. The thermal stability of the 11-cis-retinal-bound form of the E134Q/M257Y mutant was lower than that of the mutants containing a single replacement but higher than that of the all-trans-retinal-bound forms. The mutant also showed a lower stability in its opsin state as compared with that of the wild-type opsin but had little effects on the binding affinity to 11-cis-retinal. Information obtained in this study will be helpful for analyzing the structural changes associated with the activation of rhodopsin and GPCRs.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.630-635
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• 2001

The stem thrust required to unwedging a gate valve is influenced by the pressure and temperature when the valve is closed and by the changes in these conditions between closure and opening. "Pressure Locking" and "Thennal Binding" refer to situations where pressure and temperature effects cause the unwedging load to be much higher than normal. A model of these phenomena has been developed. The effects of pressure and temperature are analyzed to determine the change in this disk-to-seat "interference". Flexibilities or Stiffness of the disk and body strongly influence the unwedging thrust. Calculation and limited comparison to data have been performed for the RHR motor operated valve designs and scenario. Pressure changes can increase the unwedging thrust when bonnet pressure exceeds the pressure in the adjacent piping and temperature changes can increase the unwedging thrust when a temperature change after closure produces an increase in the disk-to-seat interference.

• Macromolecular Research
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• v.13 no.2
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• pp.141-146
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• 2005

Calix[4]crown-6-2,4-bis(4-aminobutyl ether), which has a crown-6 moiety at the 1,3-position and amino function at the 2,4-position, was prepared as an intermediate for the subsequent synthesis of calix[4]crown-6-containing polyamide and polyimide using adipoyl chloride and 1,2,4,5-benzenetetracarboxylic dianhydride. The chemical structures were characterized by IR, $^{1}H NMR$ spectroscopy and elemental analysis, and some of their physical properties, including their thermal behavior, were examined. The ion binding characteristics of the monomer and polymers for alkali metal and alkali earth metal ions were measured by liquid-liquid extraction from the aqueous phase into the organic phase. It has been observed that polyamide has a high binding ability towards various metal cations as compared to polyimide, which showed cesium ion selectivity.

• Journal of Microbiology and Biotechnology
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• v.31 no.5
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• pp.676-685
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• 2021

RNA-binding proteins are involved in RNA metabolism and posttranscriptional regulation of various fundamental biological processes. The PUF family of RNA-binding proteins is highly conserved in eukaryotes, and its members regulate gene expression, mitochondrial biogenesis, and RNA processing. However, their biological functions in Aspergillus species remain mostly unknown in filamentous fungi. Here we have characterized the puf genes in the model organism Aspergillus nidulans. We generated deletion mutant strains for the five putative puf genes present in the A. nidulans genome and investigated their developmental phenotypes. Deletion of pufA or pufE affected fungal growth and asexual development. pufA mutants exhibited decreased production of asexual spores and reduced mRNA expression of genes regulating asexual development. The pufE deletion reduced colony growth, increased formation of asexual spores, and delayed production of sexual fruiting bodies. In addition, the absence of pufE reduced both sterigmatocystin production and the mRNA levels of genes in the sterigmatocystin cluster. Finally, pufE deletion mutants showed reduced trehalose production and lower resistance to thermal stress. Overall, these results demonstrate that PufA and PufE play roles in the development and sterigmatocystin metabolism in A. nidulans.

• Journal of the Korean Ceramic Society
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• v.45 no.9
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• pp.497-506
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• 2008

The long time of twenty years has passed since Diesel Particulate Filter (DPF) was proposed before the practical use. The main factors that DPF has been put to practical use in this time, are the same time proposal of the evaluation method of SiC porous materials linked to he performance on the vehicle, and that the nature of thermal shock required for the soot regeneration (combustion of soot) in the DPF is different from the conventional requirement for the rather rapid thermal shock. For the requirements, these includ demonstrating utmost the characteristic of SiC's high thermal conductivity, and overcoming the difficulty of thermal expansion of SiC-DPF by dividing the filter into segments binding with the cement of lower Young's modulus, and the innovation of technology around the diesel exhaust system such as Common-Rail system. As the results of these, the cumulative shipments of SiC-DPF have reached about 5 million, and it goes at no claim in the market.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.95-98
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• 2005

This paper proposes the solutions predicting the coefficient of the thermal expansion changes of composites which include the fiber-like shaped ($a_1$ > ($a_2$ = ($a_3$) and the disk-like shaped (al = a2> a3) inclusions like two dimensional geometries, which has one aspect ratios, ${\alpha}$ = ($a_1$ /($a_3$). The analysis follows the procedure developed for elastic moduli by using the generalized approach of Eshelby’s equivalent tensor. The influences of the aspect ratios, on the effective coefficient of thermal expansion of composites containing aligned isotropic inclusions are examined. This model should be limited to analyze the composites with unidirectionally aligned inclusions and with complete binding to each other of both matrix and inclusions having homogeneous properties. The coefficient of thermal expansion of composites (${\theta}_{11}$,${\theta}_{22}$and ${\theta}_{33}$) are investigated. From material data of the composites with glass fiber in epoxy resin, the thermal expansions along the aspect ratio were obtained and similar to the Chow model. The longitudinal coefficients of thermal expansion ${\theta}_{11}$decrease, as the aspect ratios increase. However, the transverse coefficients of thermal expansion ${\theta}_{22}$increase or decrease, as the aspect ratios increase. And both of them decrease, as the concentration increases.