• 한국환경과학회지
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• 제4권2호
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• pp.215-222
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• 1995

Thiokncillus neapolitanus R-10 isolated from sludge of night soil, showed an oxidizing activity on several malodorous sulfur compounds. The microbe successfully utilized hydrogen sulfide(H2S), methy mercaptan(MM), dimethyl sulfide(DMS) and dimethyldisulfide(DMDS) during the batch culture reaction, of which H2S was rather rapidly oxidized. To examine the ability for removal of malodorous sulfur compounds, various concentrations of sulfide substrates were supplemented separately to basal medium and their responses were investigated. As the concentration of sulfide was increased, growth was accelerated within three days of cultivation. 2.5mM was the most favorable substrate concentration of sulfide added for all cases tested. However, when the concentration of sulfur compounds were raised over 4M, they behaved as a growth inhibitor.

• 한국대기환경학회지
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• 제31권2호
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• pp.173-180
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• 2015

The purpose of this study was to fabricate a ferric nitrate impregnated activated carbon, and the performance for hydrogen sulfide by adsorption was evaluated. Sodium hydroxide was utilized to control pH in the process during generation of ferric hydroxide on the surface of the carbon. Critical mixing duration for generation of ferric hydroxide on the carbon was 48 hrs at pH 1 of the solution, in which the chemical adsorption of hydrogen sulfide was enhanced. The adsorption capacity of the impregnated carbon increased up to 0.10 g hydrogen sulfide/g carbon, which was 4.3 times higher than that of the raw carbon. Presence of FeOOH on the surface of the impregnated carbon was examined by X-ray diffraction.

• 한국환경보건학회지
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• 제14권1호
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• pp.11-22
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• 1988

Calcium oxide, lithium oxide and titanium oxide were investigated as additives of zinc oxide for the removal of hydrogen sulfide at high temperature. This experiment was performed in the range of 1.0-2.0 vol.% H$_2$S concentration at 623-873 K reaction temperature, using a thermogravimetric analyzer. A pore blocking model was found to fit the reaction rate and the kinetics data were sucessfully expressed by this model. The reactions between additive sorbents and hydrogen sulfide were first order with respect to hydrogen sulfide concentration in a gaseous mixture with nitrogen. Among the used sorbents, ZnO-CaO 0.5 at.% and ZnO-TiO$_2$ 2.0 at.% sorbents had the best additive effects on the sulfidation reaction between additive sorbents and hydrogen sulfide, whereas the ZnO-Li$_2$O sorbents were ineffective.

• Journal of Microbiology and Biotechnology
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• 제9권3호
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• pp.265-270
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• 1999

A three phase fluidized bed bioreactor immobilized with Thiobacillus sp. IW was tested to remove hydrogen sulfide and methylmercaptan with high loading rate. In a single gas treatment, the bioreactor removed 92- 98％ of hydrogen sulfide with loading rate of 15- 66 g/l/h and removed 87-98％ of methylmercaptan with loading rate of 14-60 gl/sup -1/h/sup -1/. In the mixed gas treatment, the removal efficiencies of hydrogen sulfide and methylmercaptan maintained at 89-99％ for various inlet loading rates and were not affected by the inlet loading ratio of both gases in low loading rates. When the inlet concentration of methylmercaptan increased 3.8 times and was maintained for 30 h to observe the response of the bioreactor to sudden environmental change, the removal efficiency of methylmercaptan was maintained at an average of 91％.

• Bulletin of the Korean Chemical Society
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• 제27권12호
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• pp.2023-2027
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• 2006

Dibenzyl sulfide was oxidized at the a-carbon to yield benzaldehyde in the presence of $Pd(NO_3)_2$. Oxygen itself could not oxidize the sulfide directly, instead the nitrato ligand of the palladium complex transferred oxygen to dibenzyl sulfide to form benzaldehyde. The X-ray crystal structure of the intermediate complex, cis-[$Pd(NO_3)_2${$S(CH_2C_6H_5)_2$}$_2$], revealed that the nitrato ligand was unidentate. Para-substituted dibenzyl sulfides I, $(YC_6H_4CH_2)_2S $wherein Y = $OCH_3$, $CH_3$, Cl, CN, or $NO_2$, were synthesized and reacted with palladium nitrate, and those with electron-donating substituents (Y = $OCH_3$ and $CH_3$) were good substrates for the oxidation reaction with palladium nitrate. Thus, the reaction mechanism of the oxygen transfer was proposed to include nucleophilic benzylic carbon.

• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.612-617
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• 2021

In the case of a metal sulfide electrode, it is used as an anode or cathode active material in a lithium battery. The reason is that the voltage exists between 0.8 and 2.0 V via lithium electrode and the discharge and charge capacity is high. In order to manufacture nickel sulfide for electrode, which are widely used, nano-nickel powder was sulfided using ammonium polysulfide, and single-phase NiS electrodes were manufactured through heat treatment. The prepared NiS electrode had a high initial capacity of 500 mAh/g or more, and was stabilized after 20 cycles to maintain a capacity of 400 mAh/g or more until 100 cycles.

• 한국정밀공학회지
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• 제14권7호
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• pp.22-28
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• 1997

In this paper, We have studied internal quality incluiding chemical compositions, microscopic structure and nonmetalic inclusion of test material. We have analyzed dynamic characteristics of cutting resistence and compared chip treatment of the test material. In analyzing internal quality, all of the test material have typical ferrite+pearlite structure. But, nonmetallic inclusion has oxide and sulfide inclusion has oxide and sulfide inclusion in medium carbon steel, mainly sulfide inclusion is existed in S-free cutting steel. In Ca+S-free cutting steel, calcium aluminate and sulfide complex inclusion, had low-melting point, as deformation of sulfide and oxide inclusion is existed. Machining characteristics, cutting resistence is maximum in medium carbon steel. Chip treatement are excellent in S-free cutting steel, similar to the Ca+S free cutting steel and medium carbon steel.

• Bulletin of the Korean Chemical Society
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• 제27권6호
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• pp.863-868
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• 2006

The partial least squares (PLS-1) calibration model based on spectrophotometric measurement, for the simultaneous determination of sulfite and sulfide is described. This method is based on the difference between the rate of the reaction of sulfide and sulfite with Malachite Green in pH 7.0 buffer solution and at 25 ${^{\circ}C}$. The absorption kinetic profiles of the solutions were monitored by measuring the decrease in the absorbance of Malachite Green at 617 nm in the time range 10-180 s after initiation of the reactions with 2 s intervals. The experimental calibration matrix for partial least squares (PLS-1) calibration was designed with 24 samples. The cross-validation method was used for selecting the number of factors. The results showed that simultaneous determination could be performed in the range 0.030-1.5 and 0.030-1.2 $\mu$g m$L ^{-1}$ for sulfite and sulfide, respectively. The proposed method was successfully applied to simultaneous determination of sulfite and sulfide in water samples and whole human blood.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.276.2-276.2
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• 2016

Dye-sensitized solar cells (DSCs) are promising candidates for light-to-energy conversion devices due to their low-cost, easy fabrication and relative high conversion efficiency. An important component of DSCs is counter electrode (CE) collect electrons from external circuit and reduct I3- to I-. The conventional CEs are thermally decomposed Pt on fluorine-doped tin oxide (FTO) glass substrates, which have shown excellent performance and stability. However, Pt is not suitable in terms of cost effect. In this report, we demonstrated that nickel sulfide thin films by atomic layer deposition (ALD)-using Nickel(1-dimethylamino-2-methyl-2-butanolate)2 and hydrogen sulfide at low temperatures of $90-200^{\circ}C$-could be good CEs in DSCs. Notably, ALD allows the thin films to grow with good reproducibility, precise thickness control and excellent conformality at the angstrom or monolayer level. The nickel sulfide films were characterized using X-ray photoelectron spectroscopy, scanning electron microscopy, X-ray diffraction, hall measurements and cyclic voltammetry. The ALD grown nickel sulfide thin films showed high catalytic activity for the reduction of I3- to I- in DSC. The DSCs with the ALD-grown nickel sulfide thin films as CEs showed the solar cell efficiency of 7.12% which is comparable to that of the DSC with conventional Pt coated counter electrode (7.63%).

• KSBB Journal
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• 제29권2호
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• pp.118-123
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• 2014

It was confirmed that malodor connected with an air-conditioner in an automobile is caused by microbial volatile organic compounds (MVOCs) produced by microorganisms getting into an air-conditioner when it is operating. Chemicals such as hydrogen sulfide, dimethyl sulfide, nbutyric acid, n-valeric acid, iso-valeric acid, n-octanol and toluene were detected above the odor threshold inside the automobile. The characteristics of a funky odor in the air blown into the automobile were due to detected sulfur compounds (hydrogen sulfide and dimethyl sulfide). Dimethyl sulfide was produced by microorganisms such as Aspergillus versicolor, Methylobacterium aquaticum, Herbaspirillum sp. and Acidovorax sp. In addition, the characteristics of a sour odor in the air blown into the automobile were due to detected organic acids (n-butyric acid, n-valeric acid and iso-valeric acid). N-valeric acid and iso-valeric acid were generated from Aspergillus versicolor, while iso-valeric acid was produced by Methylobacterium aquaticum. In addition, the odor intensity of the air blown into the automobile was affected by the concentration of detected sulfur compounds and organic acids. On the other hand, it is estimated that chemicals such as hydrogen sulfide, n-octanol and n-butyric acid detected in the air blown into the automobile were produced by non-identified species of microorganisms.