• Journal of Korean Society for Atmospheric Environment
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• v.14 no.E
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• pp.27-40
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• 1998

The solubility characteristics of organic compounds were studied in terms of the extraction efficiency as a function of the polarity of the organic solvent, and the acidity of water in urban aerosol samples collected in University of East Anglia (UEA), Norwich, England. The extraction efficiency of organic compounds were evaluated with respect to the organic carbon, -nitrogen and -hydrogen by means of a wide range of solvent which include polar and nonpolar organic solvents as well as acids and alkaline water. In addition, after being dissolved in aqueous solution, the aqueous chemistry of organic compounds were studied in terms of the organic metal complexes in aerosol, which were studied with oxalic acid, copper, and zinc. The results of this study indicate that solubility characteristics of organic compounds depend on the polarity of the solvents and the acidity of the solvents. In particular, some organic compounds are water soluble, even though they are much smaller than acetone soluble fractions. In the comparison between polar organic solvent extraction and non- polar organic solvent extraction, it can be thought that significant fraction of organic compounds analysed in the aerosol samples, are polar organic compounds because of the higher extraction efficiencies of organic compounds in polar organic solvent extraction than in nonpolar organic solvent extraction. Regarding the study of the oxalic -metal complexes, it can be thought that most oxalic acids are present in the form of oxalic -copper complexes in the aerosols collected at UEA.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.3-8
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• 2000

Chemical nature of nascent metal surfaces which is one of the important active sources for tribochemical reactions was investigated using a newly developed method. Some enhanced activities were observed. For example, organic compounds chemisorbed on nascent gold surfaces and aromatic compounds decomposed on nascent nickel surfaces resulting in hydrogen evolution. Non-polar compounds such as organic sulfides had a higher chemisorption activity on nascent steel surfaces than polar compounds such as fatty acids and phosphates. Organic sulfides reacted directly with nascent steel surfaces and the surface was covered with metal sulfides. The activity for the chemisorption of organic compounds was closely dependent on the electronic structure of metals. Although benzene chemisorbed very easily on nascent surfaces of transition metals, it did not chemisorb ell nascent surfaces of simple metals. Boundary lubricating behaviors of extreme pressure additives were explained on the bases of the chemical activities of nascent surfaces obtained in this investigation. Under mild conditions, polar compounds such as fatty acids and phosphates were effective for boundary lubrication, because surfaces are covered with oxide layers. On the other hand, sulfides were more effective under severe conditions where the oxide layers were removed and the nascent surfaces were formed.

• Journal of Korean Ophthalmic Optics Society
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• v.14 no.4
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• pp.83-87
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• 2009

Purpose: This study was performed to detect various chemicals such as metal elements and volatile organic compounds which contained in mascara and we analyzed 5 sorts of mascaras frequently used by people. Methods: We purchased five sorts of mascaras commercially available and analyzed for detecting metal elements and volatile organic ingredients. Results: We found somewhat high concentration of aluminum and manganese and several organic compounds in some samples. Conclusions: The results suggest that mascara has metal elements and organic compounds which can influence to eye.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.513-522
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• 2019

Catalysts based on organic compounds, transition metal and metal-organic frameworks (MOFs) have been applied to degrade or remove organophosphorus toxic compounds (OPs). During the last 20 years, various MOFs were designed and synthesized to suit application purposes. MOFs with $Zr_6$ based metal node and organic linker were widely used as catalysts due to their tunability for the pore size, porosity, surface area, Lewis acidic sites, and thermal stability. In this review, effect on catalytic efficiency between MOFs properties according to the structure, stability, particle size, number of connected-ligand, organic functional group, and so on will be discussed.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2162-2190
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• 2007

The newly-developed Meerwein-Ponndorf-Verley (MVP) type reagents using aluminum, boron and other metals for reduction of organic functional groups such as carbonyl and epoxy compounds have been surveyed. highlighted and reviewed in this account are the appearance of new MPV type reagents and their application to the selective reduction of organic functions. Finally, this account emphasizes the distinct contrast in the reducing characteristics existed between metal hydride reagents and MPV reagents, and compares their usefulness in organic synthesis.

• Environmental Engineering Research
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• v.17 no.2
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• pp.103-110
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• 2012

This study was performed mainly to examine whether a city with a metal industrial presence presents different characteristics in ambient volatile organic compound (VOC) concentrations compared to residential (RES) and commercial/residential combined (CRC) areas of another city by using long-term monitoring data (from January 2006 to February 2009). For most target VOCs, ambient concentrations in the metal-industrialized city were lower than for the RES and CRC areas. Aromatic compounds were the predominant VOC groups for the metal industry city as well as for other land uses. The ambient concentrations of aromatic VOCs were higher in the winter and spring seasons than in the summer and fall seasons, whereas those of chlorinated VOCs did not show any distinctive variations. In addition, higher concentrations were observed during daytime hours. The correlations between the ambient target compounds were statistically significant, except for the correlation between benzene and ozone.

• Economic and Environmental Geology
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• v.57 no.4
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• pp.371-386
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• 2024

This paper presents analytical insights regarding into the occurrence of gold within organic matter, which is hosted by solid bitumen and closely associated with uranium ores in the Late Permian Kővágószőllős Sandstone Formation in Western Mecsek, South-West Hungary. The study utilizes a range of analytical techniques, including X-ray powder diffraction (XRPD) and wavelength dispersive X-ray fluorescence (WD-XRF) for comprehensive mineralogical and elemental analysis; organic petrography and electron microprobe analysis for characterizing organic matter; and an organic elemental analyzer for identifying organic compounds. A three-step sequential extraction method was used to liberate gold from organic matter and sulfide minerals, employing KOH, HCl, and aqua regia, followed by inductively coupled plasma optical emission spectroscopy (ICP-OES) to quantify gold contents. The organic matter is identified as comprising two vitrinite types (telinite V1 and reworked V2) and three solid bitumen forms: nonfluorescing (B1) and fluorescing (B2) fillings within the V1, as well as homogenous pyrobitumen (PB) occupying narrow cracks and voids within globular quartz. Despite the samples exhibiting low total organic carbon content (<1 wt%), they display high sulfur content (up to 6 wt%) and the sequentially extracted noble metal content from the organic matter is found to total 7.45 ppm gold. The research findings suggest that organic matter plays crucial roles in ore mineralization processes. Organic matter acts as an active component in the migration of gold, uranium, and hydrocarbons within sulfur-rich hydrothermal fluids. Additionally, organic matter contributes to the entrapment and enrichment of gold in hetero-atomic organic fractions, forming metal-organic compounds. Moreover, uranium inclusions are observed as oxide/phosphate minerals within solid bitumen and associated vitrinite particles. These insights into the occurrence and distribution of gold within organic matter highlight substantial exploration potential, guiding additional research activities focused on organic matter within the Kővágószőllős Sandstone Formation at the Western Mecsek deposit.

• Korean Journal of Chemical Engineering
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• v.36 no.6
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• pp.975-980
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• 2019

Infrared (IR) spectroscopy is a powerful technique for observing organic molecules, as it combines sensitive vibrational excitations with a non-destructive probe. However, gaseous volatile compounds in the air are challenging to detect, as they are not easy to immobilize in a sensing device and give enough signal by themselves. In this study, we fabricated a thin nanocrystalline metal-organic framework (nMOF) film on a surface plasmon resonance (SPR) substrate to enhance the IR vibration signal of the gaseous volatile compounds captured within the nMOF pores. Specifically, we synthesized nanocrystalline HKUST-1 (nHKUST-1) particles of ca. 80 nm diameter and used a colloidal dispersion of these particles to fabricate nHKUST-1 films by a spin-coating process. After finding that benzene was readily adsorbed onto nHKUST-1, an nHKUST-1 film deposited on a plasmonic Au substrate was successfully applied to the IR detection of gaseous benzene in air using surface-enhanced IR spectroscopy.

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1588-1592
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• 2009

Lithium cyanoaluminum hydride (LCAH) was prepared by the metal cation exchange reaction of sodium cyanoaluminum hydride with lithium chloride in tetrahydrofuran. The reducing characteristics of LCAH were explored systematically by the reaction with selected organic compounds containing representative functional groups under the standardized conditions (tetrahydrofuran, 0 ${^{\circ}C}$). The reducing ability of LCAH was also compared with of the sodium derivative, sodium cyanoaluminum hydride (SCAH). Generally, the reducing behavior of LCAH resembles that of SCAH closely, but the reactivity of LCAH toward representative organic functional groups appeared to be stronger than that of SCAH. Thus, the regent reduces carbonyl compounds, epoxides, amides, nitriles, disulfides, carboxylic acids and their acyl derivatives to the corresponding alcohols or amines, at a relatively faster rate than that of SCAH. The cyano substitution, a strong election-withdrawing group, diminishes the reducing power of the parent metal aluminum hydrides and hence effects the alteration of their reducing characteristics.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.370.1-370.1
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• 2016

Volatile organic compounds (VOCs) are considered hazardous air pollutants and these are emitted from building materials and household products. VOCs can cause global warming as well as human sickness, and even cancer. Photocatalysis provides a way of converting VOCs into harmless materials. Various researches have shown that $TiO_2$ is the most efficient photocatalysts due to its excellent activity. In this study, metal/non-metal doped $TiO_2$ particles are synthesized for the enhancement of the photocatalytic properties of pure $TiO_2$. By metal/non-metal doping, band gap energies of prepared samples were analyzed by UV/Visible spectrophotometer. The physical and chemical properties of synthesized powder were characterized by field emission scanning electron microscope, by BET for measuring their specific surface area, and by XRD for phase identification and particle size determination. Degradation ability for p-xylene was evaluated through monitoring the concentration in a closed chamber. Relation between their properties and decomposition abilities for VOC were evaluated based on the experimental results.