• Journal of Adhesion and Interface
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• v.15 no.1
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• pp.22-30
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• 2014

Self-photoinitiating acrylate (SPIA) which can undergo self-initiation under UV irradiation was synthesized by a Michael addition in the presence of a base catalyst. The SPIA polymerizations were investigated by photo-differential scanning calorimeter (photo-DSC) and surface physical properties such as pendulum hardness and pencil hardness. The results showed that the SPIA can cure upon UV irradiation by itself without a photoinitiator. But we found out that both the curing rate and the conversion were too low for the self-curing reaction of SPIA. In order to improve the SPIA curing properties, we introduced the SPIA/cationic hybrid system and observed the effects of the addition of commercial free radical type monomer and photoinitiator on the curing behaviors. SPIA/cationic hybrid system was the best suitable to improve the SPIA curing properties. The kinetic analysis indicated that the cationic monomer and photoinitiator apparently accelerated the cure reaction and rate of the hybrid SPIA system, mostly due to the synergistic effect of cationic monomer and photoinitiator increasing the mobility of active species and the generation of reactive species (free radical, cation) during the photopolymerization process. The physical properties showed that, unlike typical free radical system, the hybrid systems did not show oxygen inhibition effect because of cationic reaction on the coating surface.

• Bulletin of the Korean Chemical Society
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• v.26 no.8
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• pp.1281-1285
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• 2005

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1170-1176
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• 2012

An efficient one-pot synthesis of acridinediones by $In(OTf)_3$-catalyzed reactions was developed starting from ${\beta}$-enaminones, aldehydes, and cyclic 1,3-diketones. The key strategies of these reactions involve domino Knoevenagel condensation/Michael addition/cyclodehydration reaction.

• Journal of the Korean Applied Science and Technology
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• v.14 no.1
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• pp.27-32
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• 1997

Furfurylidene acetophenone derivatives were synthesis, it was measured that nucleophilic addition made use of UV at a wide pH 1.0${\sim}$13.0 range in 30% dioxane-$H_2O$ solution, 25$^{\circ}C$. On the basis of general base catalysis, substitutent effect, confirmation of nucleophilic addition products, it was measured the reaction rate of furfurylidene acetophenone derivatives for the pH change. It may be concluded that a part was unrelated to pH and another part was in proportion to concentration of hydroxide ion: Above pH 10.0. sulfide anion adds to the double bond (Michael type addition), a part having no concern with pH, addition reaction to double bond is initiated by addition of neutral thiourea molecule. From the result of measurement the reaction rate, nucleophilic addition of furfurylidene acetophenone derivatives confirmed to the irreversible first order. Through measurement the substituent effect. It found that reaction rate was accelerated by electron attracting group. On the basis of these findings, nucleophilic addition of thiourea for the furfurylidene acetophenone derivative was proposed a fitting mechanisms.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.2
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• pp.233-241
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• 2021

A series of three bench-scale experiments was performed to investigate the conversion of sodium metal to sodium chloride via reactions with non-metal and metal chlorides. Specifically, batches of molten sodium metal were separately contacted with ammonium chloride and ferrous chloride to form sodium chloride in both cases along with iron in the latter case. Additional ferrous chloride was added to two of the three batches to form low melting point consolidated mixtures of sodium chloride and ferrous chloride, whereas consolidation of a sodium-chloride product was performed in a separate batch. Samples of the products were characterized via X-ray diffraction to identify attendant compounds. The reaction of sodium metal with metered ammonium chloride particulate feeds proceeded without reaction excursions and produced pure colorless sodium chloride. The reaction of sodium metal with ferrous chloride yielded occasional reaction excursions as evidenced by temperature spikes and fuming ferrous chloride, producing a dark salt-metal mixture. This investigation into a method for controlled conversion of sodium metal to sodium chloride is particularly applicable to sodium containing elevated levels of radioactivity-including bond sodium from nuclear fuels-in remote-handled inert-atmosphere environments.

• Journal of the Korean Chemical Society
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• v.40 no.10
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• pp.663-669
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• 1996

The rate constants for the nucleophilic addition reactions of thioglycolic acid to vinylsulfilimine(VSI) derivatives(p-OCH3, H, p-Cl and p-Br) were determined by an ultraviolet spectrophotometric method, and rate equations which can be applied over a wide pH range were obtained. On the basis of rate equation, general base catalysis and substituent effect, a plausible addition reaction mechanism was proposed: Below pH 3.0, the reaction was proceeded via the addition of neutral molecule to carbon-carbon double bond after protonation at the nitrogen atom of the sulfilimine, and in the pH range of 3.0 to 9.0, the neutral molecule and its anion attacked to carbon-carbon double bond competitively. Above pH 9.0, sulfide anion added to the double bond (Michael type addition).

• Bulletin of the Korean Chemical Society
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• v.29 no.4
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• pp.790-794
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• 2008

Nucleophilic addition reaction of benzenethiols (PhSH) to 1-(2-nitrovinyl) benzenes ($\beta$ NS) in the presence of triethylamine (TEA) has been studied in acetonitrile at 25 ${^{\circ}C}$. The rate is first order with respect to [PhSH], [TEA] and [$\beta$ NS]. The reaction is found to proceed with the formation of ion-pair between benzenethiol and TEA. A suitable mechanism with the formation of an adduct between ion-pair and substrate in a slow step followed by its rearrangement to 1,2-addition product in a fast step has been proposed and corresponding rate law derived. From the rate law, the rate constants for the interaction between ion-pair and $\beta$NS have been evaluated. Interestingly, in both para-substituted substrates and benzenethiols the rate increases with the electron-withdrawing power of the substituents. The positive sign of $\rho_x$ in benzenethiols has been explained. The magnitude of cross-interaction constant, $\rho_{xy}$ is small (0.08). The magnitude of the Hammett $\rho_x$ values is higher than that of the Bronsted, $\beta_x$ values for benzenethiols. The kinetic isotope effect, $k_H/k_D$, is found to be greater than unity. A suitable transition state with simultaneous formation of $C_\beta$ -H and $B_\alpha$ -S bonds involving the ion-pair and $\beta$NS in a single concerted step has been proposed to account for these observations.

• Journal of the Korean Chemical Society
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• v.35 no.3
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• pp.268-274
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• 1991

The rate constants for the nucleophilic addition reactions of thiourea to ${\beta}$-nitrostyrene derivatives(p-H, p-Cl, p-CH$_3$, p-OCH$_3$, p-NO$_2$) were determined by UV spectrophotometer and rate equations which can be applied over a wide pH ranges were obtained. On the basis of substituent effect, general base catalysis and rate equations, a reaction mechanism was proposed and revealed quantitively. Above pH 9.00, sulfide anion adds to the double bond(Michael type addition) and between pH 7.00 and 9.00, the neutral molecules and its anions add to the double bond competitively. Below pH 7.00, the addition reaction to double bond is initiated by the addition of neutral thiourea molecule.

• Journal of the Korean Chemical Society
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• v.53 no.3
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• pp.308-324
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• 2009

The present work is devoted to study the interaction of $\beta$-aroylacrylic acid derivative (3) with malononitrile in (DMF) in the presence of piperidine and/or ammonium acetate, then using the formed compounds as starting materials for synthesizing fused and isolated heterocyclic systems. It has been established that the $\beta$-aroylacrylic acid (3) reacts with malononitrile in (DMF) in the presence of piperidine as a catalyst with the formation of 4H-pyran derivative (4). By changing the catalyst into ammonium acetate, pyridine derivative (5) has been obtained. Also the N-maleamic acid derivatives (19) and (27) have been synthesized via the interaction of (4) and (5) with maleic anhydride. The purpose of this step is to study the behavior of the formed maleamic acid derivatives – as analogies of $\beta$-aroylacrylic acids – towards different active methylene compounds under Michael addition reaction.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.1
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• pp.1-18
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• 2020

Molten salt solutions consisting of eutectic LiCl-KCl and concentrations of samarium chloride (0.5 to 3.0 wt%) at 500℃ were analyzed using both cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The CV technique gave the average diffusion coefficient for Sm³⁺ over the concentration range. Equipped with Sm³⁺ diffusion coefficient, the Randles-Sevcik equation predicted Sm³⁺ concentration values that agree with the given experimental values. From CV measurements; the anodic, cathodic, and half-peak potentials were identified and subsequently used as a parameter to acquire EIS spectra. A six-element Voigt model was used to model the EIS data in terms of resistance-time constant pairs. The lowest resistances were observed at the half-peak potential with the associated resistance-time constant pairs characterizing the reversible reaction between Sm³⁺ and Sm²⁺. By extrapolation, the Voigt model estimated the polarization resistance and established a polarization resistance-concentration relationship.