• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.328-333
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• 2004

To treat a waste gas containing a high strength H2S, the two-stages microbial desulfurization process that conof a bioreactor immobilized with Acidithiobacillusferrooxidans and a chemical absorption scrubber has was proposed. After 4 times repeat of batch cultures, the immobilized bioreactor has been stabilized and the rate of iron oxidation reached 0.89 kg . $m^{-3}{\cdot}m^{-1}$ at steady state. The two-stages microbial desulfurization prowas able to be operated for a long term over 54 days. The removal efficiencies of H2S were 97-99% at a space velocity of 70 h-I and a inlet concentration of 37,000 ppmv. The maximum elimination capacity of H2S was approximately 3.3 kg S . $m^{-3}{\cdot}m^{-1}$. In the bioractor, the concentrations of the $Fe^{3+}$ and the immobilzed cell were constantly maintained during the desulfurization.

• Membrane Journal
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• v.19 no.3
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• pp.244-251
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• 2009

In this research the polyethersulfone hollow fiber membrane was used to separate Sulfur Hexafluoride ($SF_6$) which is the one of the six greenhouse gases from Air ($N_2$). The effects of the non-solvent (Acetone, Ethanol) type, air-gap and post-treatment (surface silicon coating) were investigated by the structure and performance of the membranes. The structure change of the membrane was examined by scanning electron microscope. The single gas permeation using $N_2$, $SF_6$ through the membrane surface coated with silicon showed maximum 7.64 perm-selectivity improved 3.4 times.

• Journal of the Korean institute of surface engineering
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• v.53 no.2
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• pp.72-79
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• 2020

Two Fe-Cr steels of T22 steel and STS430 steel were corroded at 650 and 750℃ for 100hr in sewage sludge-(0.3% SO₂-6% O₂-10% H₂O-balance CO₂) mixed gas environment. T22 steel corroded faster than STS430, indicating that the Cr content significantly influence the corrosion rates. T22 formed thick and non-protective Fe₂O₃ as the major oxide and Fe₃O₄ as the minor one. With an increase in corrosion temperature, their corrosion rates increased, being accompanied with formation of pores and cracks in the thickened oxide scales that were non-adherent. STS430 steel formed Fe₂O₃, Fe₃O₄ as the outer scale and (Fe, Cr)-O as the inner layer by which its corrosion rate is greatly reduced. Both the T22 and STS430 steel samples formed multi-layered scales by outward diffusion of Fe ions and inward diffusion of oxygen and sulfur ions at high-temperature more than 650℃.

• Clean Technology
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• v.2 no.1
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• pp.69-79
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• 1996

Sulfur emission control in coal gasification plants implies the removal of $H_2S$ from the fuel gas in the gas clean-up system. In this study, the effects of particle size of sorbents, temperature of sulfidation and sorbent characteristics on the $H_2S$ removal efficiency of manganese ore were investigated. Experimental results showed that the removal efficiency of $H_2S$ was optimum when the temperature was about $700^{\circ}C$. And that the smaller particle size, the higher the $H_2S$ removal efficiency, but that was not effective very much. As the temperature increases, the reactivity of sorbents has lowered because agglomeration of sorbents increased the intraparticle transport resistance. This phenomenon was confirmed by SEM photographs. The equilibrium ratio ($P_{H_2O}/P_{H_2S}$) obtained by experiments is represented as a ${\log}(P_{H_2O}/P_{H_2S})=5653/T-3.7909$. It was showed that the natural manganese ore could be used as a sorbent because its capacity for $H_2S$ removal is equivalent to the eariler developed sorbents.

• Clean Technology
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• v.18 no.1
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• pp.22-30
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• 2012

Separation of $SO_2$ from the flue gases of fossil fuel power plants are important issue because of its strong environmental impact. Industrially, $SO_2$ is being removed with a slurry of limestone, lime or aqueous caustic soda. However, these scrubbing processes possess several drawbacks such as the generation of huge amount of wastewater and the production of metal salts. Recently, ionic liquids have gained increasing interest as an absorbent for acid gas, $CO_2$ and $SO_2$. In this review, we have introduced the recent progress of ionic liquids as a $SO_2$ absorbent.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.217-222
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• 2015

BACKGROUND: Garlic (Allium sativum) contains polyphenols and sulfur compounds that are recognized as antioxidant, antithrombotic, anticancer, antibacterial, antimicrobial, nematicidal, and insecticidal activity. For this reason, the Environmentally-friendly Agriculture Promotion Act allowed the garlic extract as commercial biopesticide material for crop protection, nine commercial biopesticides containing A. sativum extract have been marketed in Korea. METHODS AND RESULTS: The determination of allylmethyl sulfide (AMS), dimethyl disulfide (DMDS), and dipropyl sulfide (DPS) in biopesticides containing A. sativum extract was developed and validated by gas chromatography (GC) mass spectrometry (MS) with head-space sampler. The developed method was validated, and the limit of quantification (LOQ) and recovery rates of AMS, DMDS, and DPS were 0.08, 0.32, and 0.09 mg/L and 90.3-91.3, 86.2-88.3, and 87.6-89.5%, respectively. From the nine commercial biopesticide samples, contents of AMS, DMDS, and DPS were analyzed using the developed method and results showed

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.7
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• pp.48-56
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• 2014

Engine oil is an oil used for lubrication of various internal combustion engines. The main function is to reduce wear on moving parts; it also cleans, inhibits corrosion, improves sealing, and cools the engine by carrying heat away from moving parts. In engines, there are parts which move against each other. Otherwise, the friction wastes the useful power by converting the kinetic energy to heat. Those parts were worn away, which could lead to lower efficiency and degradation of the engine. It increases fuel consumption, decreases power output, and can induce the engine failure. This study was conducted to evaluate the relation between engine oil property changes and engine performance for the diesel engine. This test was performed by using 12L, 6 cylinder, heavy duty engines. Low SAPS 10W30 engine oil (two type engine oils) was used. Test procedure and method was in accordance with the modified CEC L-57-T97 (OM441LA) method. In this study, TAN, TBN, KV and metal components, engine power, blowby gas, A_F were presented to evaluate the relation with engine oil property changes and engine performance. TAN, TBN, KV and metal We found that the components were generally increased but engine performance did not change. This results mean that property changes did not affect on engine performance because those were not enough to affect engine performance.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.154-162
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• 2016

The aim of this study was to develop a transgenic petunia with enhanced resistance to sulfur dioxide ($SO_2$) gas by stacking two genes, SOD2 and NDPK2, which are both known to confer resistance to abiotic stresses. The first-generation hybrids ($TF_1$) were obtained through reciprocal crosses between an SOD2-transgenic line SOD2-2-1-1-35($T_4$)[S($T_4$)] and an NDPK2-transgenic line NDPK2-7-1($T_2$)[N7-1($T_2$)]. Approximately 32.1-73.0% of the first-generation hybrids ($TF_1$) carried both SOD2 and NDPK2 genes. These hybrids showed 2.6 and 5.1 times less damage than hybrids carrying only SOD2 or NDPK2 genes, respectively, when they were treated with $SO_2$ gas at 30 ppm. This confirmed that the heterozygous hybrids were more resistant to $SO_2$ than the hybrids carrying either one of the resistance genes. Second-generation hybrids ($TF_2$) were obtained by selfing the $TF_1$ individuals. We confirmed the expression of the stacked genes in the $TF_2$ hybrids by phenotypic observation of their response to $SO_2$ gas at 30 ppm as well as using RT-qPCR and photosynthetic efficiency.

• Preventive Nutrition and Food Science
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• v.10 no.1
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• pp.11-16
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• 2005

Enzymatic hydrolysis of dark muscle of skipjack was optimized by using response surface methodology. Three factors of independent values were pH (4.2 to 9.8), time (0.6 to 3.4 hrs) and temperature (34℃ to 76℃), and independent values were optical density and brix. The optimum conditions for enzymatic hydrolysis were pH 7.0 to 8.0, 55℃ and 3 hrs. The headspace volatile compounds of reaction flavors using the enzymatic hydrolysate, cysteine and xylose were identified by using the combination of a canister system, gas chromatography and mass selective detector. Among 67 compounds, we identified 8 sulfur-containing compounds and 7 furans which were thought to be highly related to meat-like flavors.

• Particle and aerosol research
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• v.6 no.4
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• pp.173-183
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• 2010

The high temperature pleated filter bags which were used during this study were made of pleated nonwoven fabric of heat and acid resistant polysulfonate fibers which can withstand the heat up to $300^{\circ}C$ and have a filtration area which is 3 to 5 times larger than the conventional round filter bags. Cartridge module packed with 3 kind of the sulfur impregnated activated-carbon based sorbents were inserted in the inner of the pleated filter bag. This type of pleated filter bag was designed to remove not only the particulate matter but also the gaseous elemental mercury. The electrostatic precipitator part can enhance the particulate removal efficiency and reduce the pressure drop of the pleated filter bag by agglomerated particles to form a more porous dust layer on the surface of the pleated bag which is increased the filter bag cleaning efficiency. In addition, the most of particles are separated from the flue gas stream through the cyclone and the electrostatic precipitator part which were installed at the lower part and main body part of the convergence particulate collector, respectively. Thus reduce particulate loading of the high temperature pleated filter bags were applied in this study to analyze the removal characteristics of particulate matter and gaseous elemental mercury.