• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.85.3-85.3
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• 2019

Pulsating variable is a star whose luminosity changes through periodic pulsation. There are radiative and dynamical mechanisms hidden in periodic brightness changes, and the physical quantities related with the mechanisms are also expected to vary periodically. The purpose of this study is to investigate the periodic variations of the physical quantities of the ${\delta}$ Scuti type variable, V350 Peg by simultaneous photometry and spectroscopy. In this poster, we present preliminary results on apparent magnitude and radial velocity at the surface.

• Journal of Conservation Science
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• v.21
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• pp.49-58
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• 2007

Among the treatment results of test samples of the antique lacquer-ware, the treatment with PEG#3,350 40% solution displayed excellent effect with low shrinkage ratio; in weight gain the treatment with Sucrose 19%+Glycerin 1%(t-butanol 5% in water) solution showed consistent increase. However during the impregnation process of Sucrose, the weight of the testing samples decreased by dehydration because the inner part of the test samples and the treatment solution showed concentration gradient. Therefore, we concluded longer impregnation period should be necessary to prevent dehydration. Since both higher and lower molecular weight treatment chemicals could penetrate into the wood of the lacquer-ware, air drying and conditioning after impregnation treatment with high concentration chemicals would be possible, as well as vacuum freeze-drying.

• Conservation Science in Museum
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• v.26
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• pp.13-24
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• 2021

Two wooden fish excavated from Wiryeseong Fortress on Seonggeosan Mountain in Cheonan-si, Chungcheongnam-do Province were frail due to their deterioration within the burial environment. To prevent further deformation, conservation treatment was conducted on them to strengthen the wooden materials and stabilize the dimensions. Prior to the conservation treatment, the species of wood was determined to be pine and infrared Irradiation on the patterns remaining on the wooden fish revealed that they were depictions of carp. For conservation treatment, the wooden fish were impregnated with PEG #3, 350 in a water solution with a 40% concentration, followed by freeze-drying.

• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.2
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• pp.114-119
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• 2014

Salinity and drought stresses are probably the most significant abiotic factor limiting plant's growth, also negatively affect seed germination and early seedling development. To study on effect of NaCl and PEG stress on seed germination and gene expression pattern of tall fescue, the levels of NaCl and PEG-induced water stresses were determined in first experiment. Different concentration of NaCl (0 to 350 mM) and PEG (0 to 30%) were used for seed treatment. Seed Germination percentage reduced with increasing osmotic potential of growth medium either due to NaCl or PEG. Seeds were not germinate at 350 mM NaCl or 30% PEG treatment. On the basis of the results, Kentucky31(E-) had more resistant than Fawn in both stress conditions. Furthermore, we have used an annealing control primer-based differential display reverse transcription-polymerase chain reaction method to identify salt- and drought stress-induced differentially expressed genes (DEGs) in tall fescue leaves. Using 120 annealing control primers, a total of 4 genes were identified and sequenced. The possible roles of the identified DEGs are discussed in the context of their putative role during salinity and drought stresses.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.599-607
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• 2009

A series of conjugated cyclic and linear enkephalin analogs, Tyr-c[D-A2bu-Gly-Phe-Asp(NH-X)], where X = methyl, stearyl or$ PEG_350$, and Tyr-D-Ala-Gly-Phe-Cys(S-X), where X = methyl, octyl, or farnesyl, were synthesized in solution to investigate the receptor selectivity of opioids based on Schwyzer's membrane compartment $concepts.^{5,6}$ Cyclizations of the target compounds were achieved in high yields (> 60%) employing BOP, $NaHCO_3$ in DMF despite the steric hindrance of the bulky pendant groups. In the binding assay, the hydrophobic fatty acyl conjugates retained $\mu$-receptor selectivity. The unsaturated farnesyl conjugate exhibited the increased binding affinity than the saturated stearyl conjugate for both $\mu$-and $\delta$-opioid receptors. The PEG conjugates displayed the $\delta$-receptor selectivity. The low molecular weight $PEG_350$ conjugate exhibited the increase selectivity than the high molecular weight $PEG_5000$ conjugate to the $\delta$-receptor. The results of this study support the membrane compartment concepts.

• Conservation Science in Museum
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• v.2
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• pp.19-25
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• 2000

In order to studies proper conservation treatment condition of waterlogged archaeological wood excavated from wetland in Shinchang-dong, Kwangju, 2 kinds of wooden objects were treated with PEG(Poly-Ethylene Glycol), sucrose and lactitol and their size stability and relative humidity were analyzed and compared each other. The result showed that Quercus spp. had the highest size stability in 2 Step-PEG treatment using PEG#200(MW:200) and PEG#4000 (MW:3,350) and Acer spp. was the highest in treatment using only PEG#4000. In relative humidity test after treatment 2 Step-PEG treatment showed the lowest size stability. In the meantime, sucrose and lactitol-treated sample was fast for penetration, sucrose-treated sample showed a sharp increase for penetration in as high as 84% humidity condition and medicine flew out a lot and lactitol-treated sample got enlarged with fine cracking(splitting) in relative humidity test. In relative humidity test, the samples showed cracking(splitting) in all treatment materials except for 2 Step-PEG treatment. This study showed that waterlogged archaeological wood excavated from Shinchang-dong had the highest size stability and highest adaptation to humidity change in case of treatment with 2 Step-PEG.

• Conservation Science in Museum
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• v.12
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• pp.47-52
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• 2011

The authors did conservation treatment of wooden objects excavated from Isong Sanung Fortress upon request of the Museum of Hanyang University. The authors investigated types of the trees prior to conservation treatment to find out 1 Pinus spp. and 11 Querus spp. The authors investigated paint coating of 1 wooden ware to find out No.4 of the exterior and No.3 of the interior and about 100㎛ thickness of the lacquer layer. The. conservation treatment was done to immerse wooden ware into high molecular PEG#3,350 in water solution (10 ~ 45%) and to give physical strength and to do vacuum freeze drying.

• Journal of Environmental Health Sciences
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• v.31 no.4 s.85
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• pp.241-245
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• 2005

Laccase catalyzes the oxidation and polymerization of aromatic compounds in the presence of molecular oxygen. Studies were conducted to characterize the use of polyethylene glycol (PEG) as an additive to keep up the enzymatic stability. The enzymatic activities highly remained and bisphenol A (BPA) was rapidly converted in the presence of 5 mg/l of PEC. These effects were accomplished with PEG of molecular weight 3,350. A linear relationship was found between the quantity of BPA to be converted $(10-120\;{\mu}M)$ and the optimum dose of PEC required for greater than $95\%$ conversion. This result suggests that it is the interaction between the PEG and the reaction products. In the optimum dose of PEG, the aeration of reaction mixture neither enhanced the conversion of BPA nor retarded the inactivation of the enzyme.

• Macromolecular Research
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• v.12 no.2
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• pp.195-205
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• 2004

We have synthesized new aromatic polyesters (DiPEG-HQ and DiPEG-BP) by condensation polymerization of a terephthalic acid derivative bearing a pendant oligo(oxyethylene) (DP = 7, MW = 350), which has a methoxy terminal group, and two different aromatic diols, hydroquinone and 4,4'-biphenoI. The synthesized polymers were characterized by differential scanning calorimetry (DSC), polarizing microscopy, and X-ray diffractometry for their liquid crystallinity (LC), thermal transitions, and structural morphologies in mesophases. The morphology of the LC phases depends strongly on the length of the rigid backbone repeating unit. The DiPEG-BP polymer having a longer repeating unit exhibits both layered and nematic structures before isotropization, whereas the DiPEG-HQ polymer having a shorter repeating unit shows only the layered structure in the mesophase. We found that the layer spacing for DiPEG-HQ is larger than that for DiPEG-BP. Both polymers easily form complexes with LiCF$_3$SO$_3$; we studied this complex formation by FT-IR spectroscopy. The layer spacing of the polymer-electrolyte composites increases upon increasing the amount of the lithium salt. The polymer/salt electrolyte mixtures we investigated at molar ratios of EO:salt in the range of 5-20 exhibit electrical conductivity values at 40$^{\circ}C$ of 2.4${\times}$10$\^$5/ and 1.1${\times}$10$\^$－5/ S/cm for DiPEG-HQ/LiCF$_3$SO$_3$ and DiPEG-BP/LiCF$_3$SO$_3$, respectively. At 80 $^{\circ}C$, these values are higher: 4.6${\times}$10$\^$－3/ and 1.1${\times}$10$\^$－4/ S/cm, respectively. The activation energy of conductivity depends strongly on the salt concentration.

• Conservation Science in Museum
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• v.7
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• pp.53-62
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• 2006

The wooden armor frame and various lacquerware artifacts excavated from the low swamp remains in Imdang, Gyeongsan have very weak material and lacquer coating; in case they are exposed in the air, they are likely to be shrunken and deformed immediately. The wooden armor frame has large size and it might be dissolved during freeze-drying. The lacquer coating of lacquerware blocks the penetration of chemicals and it is very likely to swell or peel off during the treatment. Therefore, to prevent the dissolution during vacuum freeze-drying, the wooden armor frame was replaced with t-butanol and impregnated in t-butanol solution with PEG#3, 350 43%, and lacquerware was impregnated in PEG#3, 350 40% solution at room temperature and freeze-dried. According to the analysis of the lacquer fragment from the lacquerware, the lid and the mounted cup was pasted with the mixture of lacquer and black pigment (soot) on the base layer after the first coating and pasted two or three times more with natural lacquer; the red lacquered wooden cup was pasted with the mixture of lacquer and black pigment on the base layer and pasted once on the middle layer. The top lacquer (red) was pasted with the mixture of iron oxide(Fe₂O₃).