• Restorative Dentistry and Endodontics
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• v.48 no.1
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• pp.8.1-8.8
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• 2023

Objectives: This study was designed to evaluate the parameters of bonding performance to root dentin, including push-out bond strength and dentinal tubular biomineralization, of a hydraulic bioceramic root-end filling material premixed with dimethyl sulfoxide (Endocem MTA Premixed) in comparison to a conventional powder-liquid-type cement (ProRoot MTA). Materials and Methods: The root canal of a single-rooted premolar was filled with either ProRoot MTA or Endocem MTA Premixed (n = 15). A slice of dentin was obtained from each root. Using the sliced specimen, the push-out bond strength was measured, and the failure pattern was observed under a stereomicroscope. The apical segment was divided into halves; the split surface was observed under a scanning electron microscope, and intratubular biomineralization was examined by observing the precipitates formed in the dentinal tubule. Then, the chemical characteristics of the precipitates were evaluated with energy-dispersive X-ray spectroscopic (EDS) analysis. The data were analyzed using the Student's t-test followed by the Mann-Whitney U test (p < 0.05). Results: No significant difference was found between the 2 tested groups in push-out bond strength, and cohesive failure was the predominant failure type. In both groups, flake-shaped precipitates were observed along dentinal tubules. The EDS analysis indicated that the mass percentage of calcium and phosphorus in the precipitate was similar to that found in hydroxyapatite. Conclusions: Regarding bonding to root dentin, Endocem MTA Premixed may have potential for use as an acceptable root-end filling material.

• Food Science and Preservation
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• v.17 no.5
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• pp.752-756
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• 2010

Lepidoptera (butterflies) extracts, traditionally employed as medicines, have various biological activities. Five species of Lepidoptera (Papilio maackii, Papilio xuthus, Pieris rapae, Eurema hecabe, and Sasakia charonda) were extracted with distilled water (DW), dimethyl sulfoxide (DMSO), ethanol (EtOH), and methanol (MeOH). Each extract was analyzed for anti-oxidant and anti-inflammatory activities using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay method, the ferric reducing ability of plasma (FRAP) test, and a cyclooxygenase-2 (COX-2) promoter assay. The results suggest that Lepidoptera extracts have valuable anti-oxidant and anti-inflammatory properties, supporting the idea that the extracts may serve as a food biomaterial(s) preventing oxidative processes and inflammatory damage.

• Toxicological Research
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• v.8 no.2
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• pp.273-284
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• 1992

It is well known that phenytoin (PHT), a commonly prescribed anticonvulsant, has teratogenicity in experimental animals and human. The major malformation induced by PHT in mouse is cleft palate. The mechanisms of the embryotoxic effects of PHT are unknown. However, PHT and synthetic glucocorticoids share several features with respect to their teratogenicity, and it was known that PHT increased maternal corticosterone level. Therefore PHT-induced cleft palate may be mediated indirectly by elevated maternal corticosterone. Recently it was reported that secalonic acid Dinduced cleft palate and elevated endogenous corticosterone level, and that such effects were antagonized by DMSO. The purpose of this work was to investigate whether the elevated maternal corticosterone is associated with the teratogenicity of PHT in the ICR mouse fetuses by treatment with PHT or PHT plus DMSO. PHT (74mg/kg, BW) was daily administered intraperitoneally on day 10~12 of gestation with and without DMSO(2ml/kg, BW), and the fetal malformation was observed on day 18. Maternal serum corticosterone and fetal PHT levels were determined by HPLC. The results are summarized as follows. 1)The percentage of cleft palate incidense in fetuses following treatment with PHT on day 10~12 of gestation was 51.7%. 2)There was a significant decrement in the cleft palate incidence in fetuses to 30.8% in the group treated with PHT plus DMSO compared with 51.7% in that with PHT alone. 3) Maternal serum corticosterone levels following treatment with PHT on day 10~12 of gestation increased by 116~343% compared with that of vehicle control. Such effect was antagonized by DMSO. 4)PHT concentration in the fetuses was not affected by DMSO. These results suggest that PHT-induced cleft-palate in fetuses seems to be closely associated with the elevation of maternal corticosterone level.

• Bulletin of the Korean Chemical Society
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• v.35 no.5
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• pp.1440-1448
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• 2014

Co(II)-tetrasulfonated phthalocyanine (CoTSP) is known to be aggregated to dimer at high concentration levels in water. A study on the aggregation of CoTSP using multivariate curve resolution analysis of the visible absorbance spectra over a concentration range of 30, 40 and 50 ${\mu}M$ in the presence of dimethyl sulfoxide (DMSO), dimethyl formamide (DMF), acetonitrile (AN) and ethanol (EtOH) in the concentration range of 0 to 3.57 M is conducted. A hard modeling-based multivariate curve resolution method was applied to determine the dissociation constants of the CoTSP aggregates at various temperatures ranging from 25, 45 and $65^{\circ}C$ and in the presence of various co-solvents. Dissociation constant for aggregation was increased and then decrease by temperature and concentration of phthalocyanine, respectively. Utilizing the vant Hoff relation, the enthalpy and entropy of the dissociation equilibriums were calculated. For the dissociation of both aggregates, the enthalpy and entropy changes were positive and negative, respectively. Molecular dynamics simulation of cosolvent effect on CoTSP aggregation was done to confirm spectroscopy results. Results of radial distribution function (RDF), root mean square deviation (RMSD) and distance curves confirmed more effect of polar solvent to decrease monomer formation.

• Journal of Electrochemical Science and Technology
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• v.11 no.4
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• pp.361-367
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• 2020

Recently, layered nickel-rich cathode materials (NCM) have attracted considerable attention as advanced alternative cathode materials for use in lithium-ion batteries (LIBs). However, their inferior surface stability that gives rise to rapid fading of cycling performance is a significant drawback. This paper proposes a simple and convenient coating method that improves the surface stability of NCM using sulfate-based solvents that create artificial cathode-electrolyte interphases (CEI) on the NCM surface. SO_x-based artificial CEI layer is successfully coated on the surface of the NCM through a wet-coating process that uses dimethyl sulfone (DMS) and dimethyl sulfoxide (DMSO) as liquid precursors. It is found that the SO_x-based artificial CEI layer is well developed on the surface of NCM with a thickness of a few nanometers, and it does not degrade the layered structure of NCM. In cycling performance tests, cells with DMS- or DMSO-modified NCM811 cathodes exhibited improved specific capacity retention at room temperature as well as at high temperature (DMS-NCM811: 99.4%, DMSO-NCM811: 88.6%, and NCM811: 78.4%), as the SO_x-based artificial CEI layer effectively suppresses undesired surface reactions such as electrolyte decomposition.

• Bulletin of the Korean Chemical Society
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• v.15 no.10
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• pp.873-881
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• 1994

The approximate rate and stoichiometry of the reaction of excess diisobutylaluminum hydride-dimethyl sulfide complex($DIBAH-SMe_2$) with organic compounds containing representative functional group under standardized conditions (toluene, $0{\circ}C$) were examined in order to define the reducing characterstics of the reagent and to compare the reducing power with DIBAH itself. In general, the reducing action of the complex is similar to that of DIBAH. However, the reducing power of the complex is weaker than that of DIBAH. All of the active hydrogen compounds including alcohols, amines, and thiols evolve hydrogen slowly. Aldehydes and ketones are reduced readily and quantitatively to give the corresponding alcohols. However, $DIBAH-SMe_2$ reduces carboxylic acids at a faster rate than DIBAH alone to the corresponding alcohols with a partial evolution of hydrogen. Similarly, acid chlorides, esters, and epoxides are readily reduced to the corresponding alcohols, but the reduction rate is much slower than that of DIBAH alone. Both primary aliphatic and aromatic amides examined evolve 1 equiv of hydrogen rapidly and are reduced slowly to the amines. Tertiary amides readily utilize 2 equiv of hydride for reduction. Nitriles consume 1 equiv of hydride rapidly but further hydride uptake is quite slow. Nitro compounds, azobenzene, and azoxybenzene are reduced moderately. Cyclohexanone oxime liberates ca. 0.8 equiv of hydrogen rapidly and is reduced to the N-hydroxylamine stage. Phenyl isocyanate is rapidly reduced to the imine stage, but further hydride uptake is quite sluggish. Pyridine reacts at a moderate rate with an uptake of one hydride in 48 h, while pyridine N-oxide reacts rapidly with consumption of 2 equiv of hydride for reduction in 6h. Similarly, disulfides and sulfoxide are readily reduced, whereas sulfide, sulfone, and sulfonic acid are inert to this reagent under these reaction conditions.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2683-2688
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• 2012

The position of the thermodynamic equilibrium for reverse thermochromic spiropyran 6-carboxylates (SP-COOHs) was easily determined in aqueous binary mixtures, such as water-methanol, water-acetonitrile and water-dimethyl sulfoxide. The existence of more than one type of interconvertible species of the ring-opened form of SP-COOH in aqueous binary solvents enables us to evaluate the molar extinction coefficients of the ring-opened species of SP-COOH and to obtain the thermodynamic parameters.

• Bulletin of the Korean Chemical Society
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• v.35 no.5
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• pp.1329-1332
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• 2014

The kinetic studies on the reactions of O,O-diethyl Z-S-aryl phosphorothioates with X-pyridines have been carried out in dimethyl sulfoxide. The free energy correlations with X in the nucleophiles are biphasic concave upwards with a break point at X = H, while those for substituent Z variations in the leaving groups are linear. The negative sign of ${\rho}_{XZ}$ implies that the reaction proceeds through a concerted mechanism for both the strongly and weakly basic pyridines. The biphasic concave upward free energy relationships with X are rationalized by a change in the nucleophilic attacking direction from frontside with the strongly basic pyridines to backside with the weakly basic pyridines.

• Journal of the Korean Vacuum Society
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• v.10 no.1
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• pp.57-60
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• 2001

We prepared uniform CdS nanowire arrays ways with lengths up to 5 $\mu\textrm{m}$ and diameters as small as 20 nm by electrochemically depositing the semiconductor directly into the pores of anodic alumina films from an electrolyte containing $CdCl_2$ and S in dimethyl sulfoxide. The nanowire arrays were characterized by scanning electron microscopy and X-ray diffraction. The deposited materials are composed mainly of hexagonal CdS with (100) preferential orientation.

• Journal of the Korean Graphic Arts Communication Society
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• v.16 no.3
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• pp.1-13
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• 1998

Some photopolymer, poly(vinyl cinnamoyl acetate)(PVCiA) was synthesized by esterification of polymer(vinyl alcohol(PVA) with monochloroacetic acid, followed by reaction poly(vinyl monochloroacetate)(PVChA) and potassium cinnamate. When esterification of PVA with monochloroacetic acid was reacted in the dimethyl sulfoxide(DMSO), in the synthesis of PVChA, it is very good yield and the successive cinnamoyl acetoxyl esterification of PVCiA can be successfully synthesized. But PVCiA is low photosensitive polymer if not added photosensitizing dyes. Here, we synthesized photosensitizing dyes. trifluoromethylindol squarylium dye derivatives(TFSQ). Indolization of 3-trifluoromethylphenyl-hydrazine formed 4- and 6-substituted indoles, the rate of 4- and 6-substituted indoles is close to unity. Absorption's coefficient of 1,3-bis(4-trifluoromethyl-1,3,3-trimethylindol) squarylium dye(TFSQ) is 7.57$\times$10\ulcorner, PVCiA added with TFSQ(3%) was highly sensitized six times than not added.