• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2335-2339
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• 2013

Relative reactivity of various Al-substituted dialkylalans ($AlR_2(X)$) in reduction of acetone has been studied with density functional theory and MP2 method. Formation of the alan dimers and the alan-acetone adduct, and the transition state for the Meerwein-Ponndorf-Verley (MPV) type reduction of the adduct were calculated to figure out the energy profile. Formation of dimeric alans is highly exothermic. Both the relative free energies for acetone-alan adduct formation and the TS barriers for the MPV type reduction with respect to alan dimers and acetone were calculated and they show the same trend. Based on these energetic data, relative reactivity of alans is expected to be; $AlR_2(Cl)$ > $AlR_2(OTf)$ > $AlR_2(O_2CCF_3)$ > $AlR_2(F)$ > $AlR_2(OMs)$ > $AlR_2(OAc)$ > $AlR_2(OMe)$ > $AlR_2(NMe_2)$. The energy profile is relatively well correlated with the experimental order of the reactivity of Al-substituted dialkylalans. It is noted that the substituents of alans have initial effects on the relative free energies for the carbonyl-adduct formation. Therefore, an $AlR_2(X)$ which forms a more stable carbonyl-adduct is more reactive in carbonyl reduction.

• Journal of the Korean Chemical Society
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• v.32 no.3
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• pp.249-259
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• 1988

The solvent effects of MeOH-solvent dimers were studied via AM1 Hamiltonian and supermolecule methods. Methanol, ethanol, acetone, dimethylsulfoxide, N,N-dimethylformamide, tetrahydrofuran, dioxane, and acetonitrile were considered as solvent molecules. Optimized geometries, electron densities, molecular energies, and hydrogen-bonding energies of monomers and dimers were calculated. We found that the stabilization energies contributed to the hydrogen-bonding were decreased in the order of dimethylsulfoxide > ethanol > N,N-dimethylformamide > acetone > methanol > tatrahydrofuran > dioxane > acetonitrile, and this order was explained by using the change of electron density and energy partition functions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.6
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• pp.1284-1291
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• 2006

This work examined improving the activity of photocatalyts by novel metal doping for the degradation of volatile organic compounds, such as formaldehyde and acetone. The activity was determined with type of dopant novel metal and volatile organic compounds. The palladium-doped $TiO_2$ was found to be improved the decomposition of acetone. The photocatalytic degradation rate for acetone was increased with decreasing temperature to $45^{\circ}C$. The optmum temperature of photocatalytic degradation rate for formaldehyde was $75^{\circ}C$. The enhancement of reaction rate with novel metal were 1.0 wt.% of palladium for acetone, 1.0 wt.% of plaitnum for formaldehyde.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.3
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• pp.289-294
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• 2021

Tungsten (W) is used as a facing material for nuclear fusion reactors, and it is used in conjunction with structural materials such as copper alloy (CuCrZr), graphite, or stainless steel. On the other hand, since tungsten is a material with a high melting point, a method that can be manufactured at a lower temperature is important. Therefore, in this study, tungsten, which is a facing material, was attempted to be manufactured using a pressure sintering method. Material properties of sintered tungsten materials were analyzed for each solvent using two types of solvents, acetone and polyethylene glycol. The sintered tungsten material using acetone as a solvent exhibited a hardness value of about 255 Hv, and when polyethylene glycol was used, a hardness value of about 200 Hv was shown. The flexural strength of the sintered tungsten material was 870 MPa and 307 MPa, respectively, when acetone and polyethylene glycol were used as solvents. The sintered tungsten material using acetone as a solvent caused densification between particles, which served as a factor of increasing the strength.

• ETRI Journal
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• v.40 no.6
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• pp.802-812
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• 2018

Disease discrimination using an electronic nose is achieved by measuring the presence of a specific gas contained in the exhaled breath of patients. Many studies have reported the presence of acetone in the breath of diabetic patients. These studies suggest that acetone can be used as a biomarker of diabetes, enabling diagnoses to be made by measuring acetone levels in exhaled breath. In this study, we perform a chemical sensor array optimization to improve the performance of an electronic nose system using Wilks' lambda, sensor selection based on a principal component (B4), and a stepwise elimination (SE) technique to detect the presence of acetone gas in human breath. By applying five different temperatures to four sensors fabricated from different synthetic materials, a total of 20 sensing combinations are created, and three sensing combinations are selected for the sensor array using optimization techniques. The measurements and analyses of the exhaled breath using the electronic nose system together with the optimized sensor array show that diabetic patients and control groups can be easily differentiated. The results are confirmed using principal component analysis (PCA).

• Journal of the Korean Society of Safety
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• v.37 no.6
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• pp.25-31
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• 2022

In this study, the spill and leak system is developed to provide real-time remote monitoring of industrial complexes where chemical accidents have been occurring every year. The spill and leak monitoring system uses IR-RCD equipment mounted on a 70m-high steel tower to detect chemical substances, thereby detecting chemical accidents such as leaks, fires, and explosions in real time. If IR-RCD equipment can actually detect chemical substances at a long distance, accurate and rapid initial response can be expected. Therefore, in order to confirm that IR-RCD equipment can detect chemical leakage accidents occurring at a long distance, acetone was selected as the experimental substance and a detection experiment was designed. The experiment was conducted using the acetone pool evaporation method at the wharf which was located 1.5 km away from IR-RCD equipment, and it was confirmed whether IR-RCD equipment could detect acetone in real time through the control monitor.

• Journal of Mushroom
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• v.21 no.3
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• pp.101-109
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• 2023

Lyophyllum decastes has been used for culinary purpose. The present study was conducted to evaluate the antioxidant and anti-inflammatory effects from methanol, acetone, and hot water extracts of L. decastes fruiting bodies. The acetone and methanol extracts showed the higher 1,1-diphenyl-2-picryl-hydrazy radical scavenging activities than that of the hot water extract at 0.5-2.0 mg/mL and was comparable to the BHT, the positive control. The ferrous ion chelating effects of the mushroom extracts at 0.5-2.0 mg/mL were significantly higher than that of BHT. The reducing power of acetone extract (2.12) was significantly lower than that of BHT (2.73) at 2.0 mg/ mL. The mushroom extracts also showed inhibitory effects on production of nitric oxide (NO), and expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide-induced murine macrophage cells in a concentration dependent manner. In vivo anti-inflammatory experiment on carrageenan-induced hind-paw edema of rat model, the acetone extract of the mushroom significantly suppressed the carrageenan-induced rat hind paw edema of rats in a dose dependently. The results suggest that the fruiting bodies of Lyophyllum decastes are a good natural resource of antioxidant and anti-inflammation.

• Journal of the Korean Chemical Society
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• v.29 no.5
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• pp.465-471
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• 1985

The rate constants for the solvolysis of anthraquinone-2-carbonyl chloride in binary solvent mixtures, methanol-acetonitrile, methanol-acetone, ethanol-acetonitrile and ethanol-acetone, have been studied by means of conductometry. Maximum rate phenomena were observed at the methanol mole fraction, $X_{MeOH}$ = 0.73~0.81 for methanol-acetonitrile and at $X_{MeOH}$ = 0.83 for methanol-acetone mixtures. The Kivinen and Grunwald-Winstein plots indicated that the reaction proceeds via $S_N2$ type mechanism. Application of Taft's solvatochromic correlation on the solvolysis rate revealed that both $\alpha$ and ${\pi}^*$ are important for reactions in methanol-acetonitrile and methanol-acetone mixtures, while only ${\alpha}$ influences significantly on the rate in ethanol-acetonitrile and ethanol-acetone mixtures.

• Resources Recycling
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• v.25 no.4
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• pp.32-41
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• 2016

The precipitation test, which is the last step of magnesium recovery process consisting of three processes (pre-precipitation, selective dissolution of magnesium, precipitation) is performed to obtain magnesium sulfate powder from seawater. In the study, we succeed in precipitating the magnesium sulfate by adding acetone into the solution of magnesium over 4 times concentrated from seawater. The yield efficiency of magnesium sulfate increases with increasing pH and the ratio of added acetone. More than 99% of magnesium is obtained as magnesium sulfate hydrate ($MgSO_4{\cdot}6H_2O$) under the following conditions; pH 1.0 ~ 1.5, and the ratio of solution and acetone 1 : 1.5 (v:v). The acetone used in the precipitation process is recovered by the fractional distillation.

• Journal of Life Science
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• v.12 no.6
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• pp.694-699
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• 2002

The present experiment was carried out to determine the effect of seed-coat softening by various chemicals, washing, chilling, and light treatment alone and in combination during desiccation of seeds on germination of gourd (Lagenaria siceraria Standl.) seeds. Potassium hydroxide, sodium hydroxide, acetone, acetonitrile, and acetamide were used as chemicals for the softening. Washing, prechilling, drying and light treatment of the softened seeds were done for a hour with tap water, for one or three weeks at 3$^{\circ}C$, 12 hr at 35$^{\circ}C$, and 14 hr a day at 3$0^{\circ}C$ with red light illumination or darkness, respectively. FR-yongjadaemok and FR-kunghap were used as test cultivars. Seed-coat softening with 10% acetone and acetonitrile for 1 hour enhanced and accelerated seed germination compared to the other chemicals and water imbibition. KOH treated for the softening was necessary to increase the germination rate of seeds for following chilling, but acetone did not influence their germinability regardless of chilling. Washing the softened seeds in tap water increased the germination rate in comparison with no-washing. During desiccation of the seeds sequentially treated with the softening, washing and chilling, red light treatment showed higher germination rate than dark one, suggesting that red light treatment are necessary during desiccation.