• Fibers and Polymers
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• v.5 no.4
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• pp.270-274
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• 2004

Blends of poly(l-lactide) (PLA) and low density polyethylene (LDPE) were prepared by melt mixing in order to improve the brittleness of PLA. A reactive compatibilizer with glycidyl methacrylate (GMA), PE-GMA, was required as a compatibilizer due to the immiscibility between PLA and LDPE. It contributes to reduce the domain size of dispersed phase and enhance the tensile properties of PLA/LDPE blends, especially for PLA matrix blends. A reaction product between PLA and PE-GMA, which was formed during melt-mixing and considered to act as a reactive compatibilizer, was characterized using $ ^1H-NMR$ spectroscopy.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.6
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• pp.652-660
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• 2004

The cis-hex-3-ene-1,5-diynyl-bridged diiron compound 3, [(η$^{5}$ - $C_{5}$ M $e_{5}$ ) Fe(dppe)］$_2$($\mu$-C≡C-CH=CH-C≡C), have been prepared and characterized by cyclic voltammetry(CV), and electronic spectroscopy (UV-VIS and near-IR, NMR). From the results, compound 3 show two well resolved, single-electron, reversible oxidation waves by CV, and comproportionation constant(Kc) calculated from the CV data for compound 3. The Mixed-valence (MV) radical cation 3$^{+}$ show strong absorptions in the near IR, 1586 nm, and this band is more readily assigned as MV $\pi$-$\pi$ band of delocalized complex (Robin-Day Mixed-valence Class III), and the $H_{ab}$ , effective coupling parameter are most consistent with electronic delocalization.

• Bulletin of the Korean Chemical Society
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• v.21 no.4
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• pp.383-388
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• 2000

Multiblock copolymers consisting of poly( g-benzyl L-glutamate) (PBLG) as the hydrophobic part and poly(ethylene oxide) (PEO) as the hydrophilic part (GEG) were synthesized and characterized. GEG polymeric micelles were prepared by the dialysis technique. Particle size distributions based on intensity,volume, and number-average were 22.6 $\pm$ 11.9 nm, 23.5 $\pm$ 4.6 nm, and 23.7 $\pm$ 37 nm, respectively. It was observed that par-ticle size and size distribution of GEG polymeric micelles changed significantly with the choice of initial sol-vent. Transmission electron micrographs (TEM) showed the polymeric micelles to be spherically shaped, with sizes ranging from 20 nm to 40 nm in diameter. Fluorescence spectroscopy measurements suggested that GEG block copolymers wereassociated in water to form polymeric micelles, and the critical micelle concentrations (CMC) value of the block copolymers was 0.0094 g/L. Further evidenceof micelle formation of GEG block copolymers and limited mobility of the PBLG chain in the core ohe micelle was obtained with 1 H NMR in D2O.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.255-256
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• 2022

We synthesized catechol-conjugated chitosan (CCC) to study its usefulness as a construction material additive in cement mortar. The degree of catechol conju-gation (DOC_cat) of the synthesized CCC was determined to be approximately14% by UV-vis and ¹H NMR spectroscopy. Furthermore, the hydroxyl and amine groups in CCC could play a crucial role in hydrogen bonding, metal coordination, and cross-linking processes via interaction with adducts from cement mortar. In this study, we observedanimprovement in the compressive strength and absorption rate, suggesting that CCC is a promising candidateforhigh-performance cement mortar.

• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.447-454
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• 2018

Zearalenone (ZEN), a mycotoxin produced by Fusarium in food and feed, causes serious damage to the health of humans and livestock. Therefore, we compared the metabolomic profiles in the liver, serum, and urine of piglets fed a ZEN-contaminated diet using proton nuclear magnetic resonance ($^1H-NMR$) spectroscopy. The spectra from the three different samples, treated with ZEN concentrations of 0.8 mg/kg for 4 weeks, were aligned and identified using MATLAB. The aligned data were subjected to discriminating analysis using multivariate statistical analysis and a web server for metabolite set enrichment analysis. The ZEN-exposed groups were almost separated in the three different samples. Metabolic analysis showed that 28, 29, and 20 metabolites were profiled in the liver, serum, and urine, respectively. The discriminating analysis showed that the alanine, arginine, choline, and glucose concentrations were increased in the liver. Phenylalanine and tyrosine metabolites showed high concentrations in serum, whereas valine showed a low concentration. In addition, the formate levels were increased in the ZEN-treated urine. For the integrated analysis, glucose, lactate, taurine, glycine, alanine, glutamate, glutamine, and creatine from orthogonal partial least squares discriminant analysis (OPLS-DA) were potential compounds for the discriminating analysis. In conclusion, our findings suggest that potential biomarker compounds can provide a better understanding on how ZEN contaminated feed in swine affects the liver, serum, and urine.

• Journal of the Korean Magnetic Resonance Society
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• v.22 no.4
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• pp.149-157
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• 2018

Diabetes is known to be one of common causes for several types of peripheral nerve damage. Diabetic neuropathy (DN) is a significant complication lowering the quality of life that can be frequently found in diabetes patients. In this study, the metabolomic characteristic of DN and Diabetes was investigated with NMR spectroscopy. The sera samples were collected from DN patients, Diabetes patients, and healthy volunteers. Based on the pair-wise comparison, three metabolites were found to be noticeable: glucose, obviously, was upregulated both in DN patients (DNP) and Diabetes. Citrate is also increased in both diseases. However, the dietary nutrient and biosynthesized metabolite from glucose, ascorbate, was elevated only in DNP, compared to healthy control. The multivariate model of OPLS-DA clearly showed the group separation between healthy control-DNP and healthy control-Diabetes. The most significant metabolites that contributed the group separation included glucose, citrate, ascorbate, and lactate. Lactate did not show the statistical significance of change in t-test while it tends to down-regulated both in DNP and Diabetes. We also conducted the ROC curve analysis to make a multivariate model for discrimination of healthy control and diseases with the identified three metabolites. As a result, the discrimination model between healthy control and DNP (or Diabetes) was successful while the model between DNP and Diabetes was not satisfactory for discrimination. In addition, multiple combinations of lactate and citrate in the OPLS-DA model of healthy control and diabetes group (DNP + Diabetes patients) gave good ROC value of 0.952, which imply these two metabolites could be used for diagnosis of Diabetes without glucose information.

• Journal of the Korean Applied Science and Technology
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• v.28 no.2
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• pp.146-151
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• 2011

In this study, by using oleic acid and polypropylene glycol, good natured antifoaming agent for suitable electronics process under the alkaline conditions were synthesized. For the synthesized mono and diesters, acid value, hydroxyl value was measured, and identified by FT-IR and $^1H-NMR$ spectroscopy. Surface properties such as surface tension, critical micelle concentration(cmc) for diluted aqueous solution was measured, and tested the antifoaming properties according to the difference of alkyl chain length, various concentration, temperature and pH. The surface tension of synthesized antifoaming agent, PPMO(Polypropylene glycol monooleate) was 24.3 dyne/cm, PPDO(Polypropylene glycol dioleate) was 23.7 dyne/cm. By increasing of the alkyl chain length, surface tension was decreased slightly, and showed good antifoaming properties at 0.06 wt% concentration and $50^{\circ}C$, pH 11. These synthesized compounds are expected to apply as a suitable antifoaming agents in the semiconductor and the PCB(Printed Circuit Board) manufacturing process.

• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.6
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• pp.32-38
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• 2017

Plasticizers play roles in increasing plasticity or fluidity during mixing. Representative plasticizers are DOS, DOA, IDP and BTTN. In particular, BTTN is an energy plasticizer that helps propellant performance and is widely used. However these compounds are sensitive relatively. So, in order to develop insensitive energetic plasticizer, synthesis of one of the derivatives of triazole, 4,5-bis (azido methyl)-(1-butyl)-1,2,3-triazole (1-DABTR), was studied. Also, the compound was characterized by NMR, IR spectroscopy, and physicochemical properties such as glass transition temperature, melting point, decomposition temperature, density, viscosity and impact sensitivity were measured. In addition, the heats of formation (${\Delta}H_f$) of 1-DABTR was also calculated using Gaussian 09.

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.605-609
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• 2003

The lower-order lithium organocyanocuprate compound, (THF)₃Li(NC)Cu($C_6$H₃-2,6-Mes₂) (1), and the bulky terphenyl Grignard reagent, Br(THF)₂Mg($C_6$H₃-2,6-Trip₂) (2), have been synthesized and structurally characterized both in the solid state by single crystal x-ray crystallography and in solution by multi-nuclear NMR and IR spectroscopy. The compound (1) was isolated as a monomeric contact ion-pair in which the C (organic ipso)-Cu-CN-Li atoms are coordinated linearly. The lithium has a tetrahedral geometry as a result of solvation by three THF molecules. The compound (1) is the first example of fully characterized monomeric lower order lithium organocyanocuprate. The bulky Grignard reagent (2) was also isolated as a monomer in which the magnesium, solvated by two THF molecules, has a distorted tetrahedral geometry. The crystals of (1) possess triclinic symmetry with the space group $P{\={1}}$, Z = 2, with a = 12.456(3) Å, b = 12.508(3) Å, c = 13.904(3) Å, α = 99.81°, β = 103.72(3)°, and γ = 119.44(3)°. The crystals (2) have a monoclinic symmetry of space group $P2_{1/C}$, Z = 4, with a = 13.071(3) Å, b = 14.967(3) Å, c = 22.070(4) Å, and β = 98.95(3)°.

• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.321-324
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• 2014

Fresh and chopped aerial parts of Oryza sativa were extracted in 80% aqueous mehthanol, and the concentrated extract was successively partitioned in n-hexane, ethyl acetate (EtOAc), n-butanol (n-BuOH), and $H_2O$ fractions. From the n-BuOH fraction, two compounds were isolated through repeated silica gel and ODS column chromatography (c.c.). Based on nuclear magnetic resonance (NMR), mass spectrometry and infrared spectroscopy spectroscopic data, the compounds were identified to be adenosine (1) and phlomuroside (2). Especially, the configuration of both the anomer hydroxyl groups was determined as ${\beta}$ from the coupling constants of the anomer protons (J =6.0 and 7.6 Hz) in the $^1H-NMR$ spectra. This is the first report for the isolation of these compounds from Oryza sativa L.