• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.305.2-305.2
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• 2016

Tin monosulfide (SnS) is one promising candidate absorber material which replace the current technology based on cadmium telluride (CdTe) and copper indium gallium sulfide selenide (CIGS) for its suitable optical band gap, high absorption coefficient, earth-abundant, non-toxic and cost-effective. During past years work, thin film solar cells based on SnS films had been improved to 4.36% certified efficiency. In this study, Tin monosul fide was obtained by atomic layer deposition (ALD) using the reaction of Tetrakis (dimethylamino) tin (TDMASn, [(CH3)2N]4Sn) and hydrogen sulfide (H2S) at low temperatures (100 to 200 oC). The direct optical band gap and strong optical absorption of SnS films were observed throughout the Ultraviolet visible spectroscopy (UV VIS), and the properties of SnS films were analyzed by sanning Electron Microscope (SEM) and X-Ray Diffraction (XRD).

• Journal of Microbiology and Biotechnology
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• v.13 no.2
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• pp.301-304
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• 2003

In this study, hydrogen sulfide ($H_2S$), ammonia ($NH_3$), and benzene, which represent the major odor from a natural leather process plant, were removed using a fluidized bed bioreactor and biofilter including Thiobacillus sp. IW and a MY microbial consortium. The critical removal rate was $12g m^{-3}h^{-1}\;for\;H_2S,\;11g m^{-3}h^{-1}\;for\;NH_3\;and\;28 g m^{-3}h^{-1}$ for benzene by the fluidized bed bioreactor, and $8.5g m^{-3}h^{-1}\;for\;H_2S\;7g m^{-3}h^{-1}\;for\;NH_3,\;and\;25 g m^{-3}h^{-1}$ for benzene in the biofilter. The average removal efficiency of $H_2S$, $NH_3$, and benzene by continuous operation for over 30 days with the fluidized bed bioreactor was $95{\pm}3\%,\;99{\pm}1\%,\;and\;98{\pm}5\%$, respectively, whereas that with the biofilter was $96{\pm}4\%,\;95{\pm}4\%,\;and\;97{\pm}3\%$, respectively. Therefore, the critical removal rate of $H_2S$, $NH_3$, and benzene was higher in the fluidized bed bioreactor, whereas the removal efficiency on the continuous operation was similar in both bioreactors.

• Journal of Wellbeing Management and Applied Psychology
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• v.5 no.2
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• pp.21-27
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• 2022

Purpose: This study is about photocatalytic technology and plasma oxidation-reduction technology. To the main cause of exposure to odor pollution, two deodorization techniques were applied to develop a module with higher removal efficiency and ozone reduction effect. Research design, data and methodology: A composite module was constructed by arranging two types of dry deodorization equipment (catalyst, adsorbent) in one module. This method was designed to increase the responsiveness to the components of complex odors and the environment. standard, unity, two types of oxidizing photo-catalyst technology and plasma dry deodorization device installed in one module to increase the potential by reduction to 76% of ozone, 100%, and 82%. Results: The complex odor disposal efficiency was 92%. Ammonia was processed with 50% hydrogen sulfide and 100% hydrogen sulfide, and ozone was 0.01ppm, achieving a target value of 0.07ppm or less. The combined odor showed a disposal efficiency of 93%, ammonia was 82% and hydrogen sulfide was 100% processed, and ozone achieved a target value of 0.07 ppm or less. Conclusions: Ozone removal efficiency was 76% by increasing Oxidation-Reduction Reaction(ORR). The H2S removal efficiency of the deodorizer was higher than that of the biofilter system currently used in sewage disposal plants.

• New & Renewable Energy
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• v.16 no.1
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• pp.68-76
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• 2020

Operational testing of the THIOPAQ^® facility that removes H₂S from landfill gas was performed for 746 days. The average H₂S removal efficiency was 99.4%, and the input quantities of air, NaOH, and nutrients per sulfur load were 13.1 ㎥/ton, 1.5 ㎥/ton, and 28.7 L/ton, respectively. The purity of the bio-sulfur produced from the facility was 94.8%, with 3.3% impurities, except for moisture. X-ray photoelectron spectroscopy showed that the compositional contents of amino acids and free amino acids of the bio-sulfur surface were 5,308 and 728 mg/kg, respectively. The mean particle size was 3.41 ㎛, which was much smaller than that of chemical sulfur. Based on these results, a high H₂S removal rate of more than 97% is feasible, and high value-added bio-sulfur, which is used as a fungicide because of its hydrophilic characteristics and small size, can be obtained at this facility.

• Journal of environmental and Sanitary engineering
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• v.22 no.2
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• pp.35-40
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• 2007

It disposes positively in the air pollution damage which is serious, in order help period the place where it improves the quality of existence and life of the local residents. It removed the offensive odor regulation material and the technique it will be able to prevent to sleep it researched it did. After scattering the GNC solution which develops the offensive odor regulation material which occurs from the food and trash treatment plant which is located to the S from the H, company after scattering the GNC solution which it develops collection it did a control criminal record control kind air and it analyzed. In this study, we investigated the emission concentrations of offensive odorous compounds of hydrogen sulfide, methyl mercaptan, dimethyl sulfide and dimethyl disulfide, trimethylamine, formaldehyde, acetaldehyde, propionaldehyde, buthylaldehyde, iso-valeric aldehyde, n-valeric aldehyde, ammonia. The concentrations of odorous compounds are determined by gas chromatography, HPLC and uv-vis spectroscopy. Hydrogen sulfide, methyl mercaptan, dimethyl sulfide and dimethyl disulfide were not detected at any point examined.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.8
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• pp.1202-1208
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• 2015

The effects of daily dietary Bacillus subtilis (Bs), and adding L-tryptophan, fructan, or casein to fecal fermentation broths were investigated as means to reduce the production of noxious gas during manure fermentation caused by ammonia, hydrogen sulfide ($H_2S$), and 3-methylindole (skatole). Eighty swine ($50.0{\pm}0.5kg$) were equally apportioned to an experimental group given Bs in daily feed, or a control group without Bs. After 6 weeks, fresh manure was collected from both groups for fermentation studies using a $3{\times}3$ orthogonal array, in which tryptophan, casein, and fructan were added at various concentrations. After fermentation, the ammonia, $H_2S$, L-tryptophan, skatole, and microflora were measured. In both groups, L-tryptophan was the principle additive increasing skatole production, with significant correlation (r = 0.9992). L-tryptophan had no effect on the production of ammonia, $H_2S$, or skatole in animals fed Bs. In both groups, fructan was the principle additive that reduced $H_2S$ production (r = 0.9981). Fructan and Bs significantly interacted in $H_2S$ production (p = 0.014). Casein was the principle additive affecting the concentration of ammonia, only in the control group. Casein and Bs significantly interacted in ammonia production (p = 0.039). The predominant bacteria were Bacillus spp. CWBI B1434 (26%) in the control group, and Streptococcus alactolyticus AF201899 (36%) in the experimental group. In summary, daily dietary Bs reduced ammonia production during fecal fermentation. Lessening L-tryptophan and increasing fructan in the fermentation broth reduced skatole and $H_2S$.

• Corrosion Science and Technology
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• v.8 no.1
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• pp.21-26
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• 2009

The influence of $H_2S$ on the corrosion of iron and the corrosion prevention mechanism of an inhibitor was investigated with a differential capacitance measurement and a weight loss measurement method. The results show that $H_2S$ accelerates both the anodic iron dissolution and the cathodic hydrogen evolution in most cases. However, $H_2S$ acts as an inhibitor of the corrosion of iron under certain special conditions. An EIS method is proposed to explain the ability of inhibitors.

• Journal of Environmental Science International
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• v.30 no.6
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• pp.501-505
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• 2021

V₂O₅-TiO₂ catalysts were prepared by various methods. V₂O₅-TiO₂ were prepared by sol-gel method with different drying conditions (aerogel and xerogel), and V₂O₅ supported on TiO₂ obtained by sol-gel method with precipitation-deposition method and impregnation method. The performance of the V₂O₅-TiO₂ catalysts was investigated for the selective oxidation of hydrogen sulfide in the stream containing both ammonia and excess water. All the catalysts showed good dispersion of vanadium and they had high H₂S conversion with no or little production of sulfur dioxide. The V₂O₅-TiO₂ aerogel catalyst prepared by sol-gel method with drying under super critical condition had the highest surface area which led to better catalytic activity compared to those by other synthesis methods.

• Journal of Biosystems Engineering
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• v.36 no.5
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• pp.342-347
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• 2011

The effect of SNC(silver nano colloid) on the emission reduction of odors such as ammonia ($NH_3$), hydrogen sulfide ($H_2S$), and methane ($CH_4$) from swine excreta was studied. Silver has been used as an universal antibiotic substance and can reduce the emission of some gases by sterilizing action. Therefore, an apparatus which produces SNC was developed and was conducted its performance test. Also, the SNC made by the apparatus was applied to swine excreta sampled from a piggery in oder to find the effect on the reduction of odor emission. An electrolysis apparatus was developed to produce SNC and its capacity was 0.024 ppm/$hr{\cdot}L$. The effects of SNC on the reduction of odor emission from swine excreta were tested for bad smell gases of ammonia ($NH_3$), hydrogen sulfide ($H_2S$) and methane ($CH_4$). For ammonia gas, factorial experiments were conducted to find the effects of concentration and application rate of SNC. The test results for the different concentrations of 20 ppm, 50 ppm, and 100 ppm showed that the more concentration of SNC was increased, the more emission reduction of ammonia gas increased. From the test results about the effect of application rate, the more SNC was applied, the more emission reduction of $NH_3$ increased. In order to reduce the concentration of $NH_3$ below 5 ppm, SNC of 50 ppm is recommended to be applied at an interval of 6 hours, and is mixed with swine excreta in the volumetric ratio of 4:1. For hydrogen sulfide gas, the concentration was decreased as time went by and was reduced rapidly in the first stage of the tests for all applied concentrations of SNC (20 ppm, 50 ppm, and 100 ppm). Especially, when 100 ml of SNC with 100 ppm was applied, emission of hydrogen sulfide gas was reduced rapidly during early 4 hours after the application of SNC. And, concentration of hydrogen sulfide gas was maintained below 20 ppm after 12 hours. For methane gas, t-test showed that there was no significance on the effect of its application for all applied concentrations of SNC. Therefore, it was concluded that the application of SNC on swine excreta had no effect on the emission reduction of $CH_4$.