• Journal of dental hygiene science
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• v.10 no.2
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• pp.101-107
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• 2010

The purpose of this study was to analysis know the important oral environmental factors which affect halitosis components of the adult in order to provide basic data for halitosis prevention and establish a device to eliminate halitosis efficiently. The 97 adults who visited at the Dental Clinic in Metropolis (M=68, F=30) participated in this study that performed from March in 2009 to in 2010. The obtained results through items as caries status, periodontal status, salivary flow, the viscosity, pH, Snyder test, plaque deposit, tongue plaque and halitosis check were as followings. The average shame of halitosis components appeared at hydrogen sulfide 36.71 ppb methyl mercaptan 31.46ppb dimethyl sulfide 54.33 ppb and Ammonia 22.60 ppm. The normality and the detection comparative result dimethyl sulfide above reverse appeared highly at 46.9%, ammonia appeared highly at 52%. According to the Hydrogen sulfide level was a high relationship among age, CPI, tongue coat status, DMFT index which were statistically significant (p<0.05). According to the quantity of hydrogen sulfide level there was relationship where tongue coat status Saliva flow rate considers statistically(p<0.05). The quantity of methyl mercaptan level there was relationship where Dimethyl sulfide level, tongue coat status, Saliva flow rate considers statistically(p<0.05). The quantity of Dimethyl sulfide level there was relationship where Hydrogen sulfide level, ammonia level, tongue coat status, Saliva pH and Saliva flow rate considers statistically(p<0.05). Ammonia level there was relationship where Methyl mercaptan level, CPI, and Saliva flow rate considers statistically(p<0.05).

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.1
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• pp.43-53
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• 2023

Sulfide concentrations critically affect worker safety and the integrities of underground facilities, such as deep geological repositories for spent nuclear fuel. Sulfide is highly sensitive to oxygen, which can oxidize sulfide to sulfate. This can hinder precise measurement of the sulfide concentration. Hence, a literature review was conducted, which revealed that two methods are commonly used: the methylene blue and sulfide ion-selective electrode (ISE) methods. Inductively coupled plasma optical emission spectroscopy (ICP-OES) was used for comparison with the two methods. The sulfide ISE method was found to be superior as it yielded results with a higher degree of accuracy and involved fewer procedures for quantification of the sulfide concentration in solution. ICP-OES results can be distorted significantly when sulfide is present in solution owing to the formation of H₂S gas in the ICP-OES nebulizer. Therefore, the ICP-OES must be used with caution when quantifying underground water to prevent any distortion in the measured results. The results also suggest important measures to avoid problems when using ICP-OES for site selection. Furthermore, the sulfide ISE method is useful in determining sulfide concentrations in the field to predict the lifetime of disposal canisters of spent nuclear fuel in deep geological repositories and other industries.

• Journal of Life Science
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• v.17 no.7 s.87
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• pp.996-1001
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• 2007

To investigate whether sulindac, sulindac sulfone, and sulindac sulfide could affect cancer cell viabilities, human colorectal HCTl16 cells were treated with 10 ${\mu}M$ of each NSAID. Among treated NSAms, sulindac sulfide dramatically decreased the cell viabilities detected by MTS and the cytotoxic effect showed dose-dependent manner. To understand the molecular mechanism of cell death in response to sulindac sulfide treatment, we performed oligo DNA microarray analysis. We found that 23 genes were up-regulated more than 2 folds, whereas 33 genes were down-regulated more than 2 folds by treatment of 10 ${\mu}M$ sulindac sulfide. Among the up-regulated genes, we selected 3 genes (NAG-1, DDIT3, PCK2) and performed RT-PCR and quantitative real-time PCR to cofirm microarray data. The results of RT-PCR and real-time PCR were highly accorded with those of microarray experiment. As NAG-1 is well-known gene as tumor suppressor, we detected changes of NAG-1 expression by 10 ${\mu}M$ of sulindac, sulindac sulfone, and sulindac sulfide. The results of RT-PCR and quantitacve real-time PCR indicated that sulindac sulfide was the strongest inducer of NAG-1 among treated NSAIDS. This result implies that induction of NAG-1 by sulindac sulfide plays important role in cell death of colorectal cancer. Overall, we speculate that these results may be helpful in understanding the molecular mechanism of the cancer chemoprevention by sulindac sulfide in human colorectal cancer.

• Journal of the Korean Chemical Society
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• v.11 no.1
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• pp.38-43
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• 1967

In order to explain the positive catalytic action of copper compound for the rate of leaching of zinc sulfide minerals, the electrode and redox potentials of both synthetic and natural sulfides were measured at various conditions of temperatures and pressures. The potentials of Chalcopyrite and copper sulfide were considerably higher than that of zinc sulfide, whereas lead sulfide and Galena had slightly lower potentials than that of zinc sulfide. At elevated temperatures and pressures, the same tendency was obtained. By means of comparing the calculated and measured values of potentials for sulfides, it was suggested that the electrode potentials in acid solution were generated by oxidation of sulfur ion. As a result, it was concluded that the catalytic action of copper compound in the leaching of synthetic zinc sulfide should be arised from the galvanic action between sulfides keeping intimate contact one another in which copper sulfide worked as cathodic and zinc sulfide as anodic part analogous to the metal corrosion under galvanic action.

• Progress in Medical Physics
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• v.14 no.3
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• pp.161-166
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• 2003

To evaluate the performance of cadmium sulfide as a multi-function X-ray dosimeter, we made an X-ray detector that was based on cadmium sulfide using evaporation technology, and measured its response to X-ray exposure. The voltages of cadmium sulfide were measured on the various X-ray tube potentials, X-ray tube currents and exposure times. The regression analysis of the voltage response of CdS on the tube-potential variation was y=0.0995x-0.1146 ($R^2$=0.9595, $\sigma$=0.08, standard error=2%) and the regression analysis of the voltage response of CdS on the tube-potential variation was y=0.0439x+1.1891 ($R^2$=0.9021, $\sigma$=0.04, standard error=1.8%) The regression analysis of the voltage response of CdS on the X-ray exposure time variation was y=8.2853+5.5878 ($R^2$=0.7287, $\sigma$=0.06, standard error=1.9%). In conclusion, cadmium sulfide responded linearly to the variation X-ray conditions, suggesting cadmium sulfide to be a feasible X-ray sensor of multi-function dosimeter related instruments.

• Journal of the Korean Electrochemical Society
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• v.14 no.4
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• pp.225-230
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• 2011

CIGS solar cells are kind of thin film solar cells, which are studied several years. CdS buffer layer that makes heterojunction between window layer and absorbing layer was one of issue in the CIGS solar cell study. New types of buffer layer consisted of indium sulfide are being studied these days owing to high price and environmental harmful of CdS. In this study, we demonstrated electrochemical synthesis of indium sulfide film as a buffer layer, which is cheaper and faster than other methods. A uniform indium sulfide film was obtained by applying two different alternating potentials. The band gap of the film was optimized by controlling temperature during the electrochemical synthesis. Using x-ray photoelectron spectroscopy and diffraction method we confirmed that ${\beta}$-indium sulfide was formed on ITO electrode surface.

• Journal of Sensor Science and Technology
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• v.32 no.3
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• pp.194-198
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• 2023

With the recent development of industrial technology, the problem of odor due to leakage of toxic gas discharged from industrial complexes is gradually increasing. Among them, hydrogen sulfide is a colorless representative odorous substance that can cause pain through irritation of the mucous membranes of the eyes and respiratory tract, and is a gas that can cause central nervous system paralysis and suffocation when exposed to high concentrations. Therefore, in order to improve the odor problem, research on a gas sensor capable of quickly and reliably detecting a leak of hydrogen sulfide is being actively conducted. A lot of research has been done on the existing metal oxide-based hydrogen sulfide gas sensor, but it has the disadvantage of requiring low selectivity and high temperature operating conditions. Therefore, in this study, a Pt/CNT-based electrochemical hydrogen sulfide gas sensor capable of detecting at low temperatures with high selectivity for hydrogen sulfide was developed. A working electrode capable of selectively detecting only hydrogen sulfide was fabricated by synthesizing Pt nanoparticles as a catalyst on functionalized CNT and applied to an electrochemical hydrogen sulfide gas sensor. It was confirmed that the manufactured Pt/CNT-based electrochemical hydrogen sulfide gas sensor has a current change of up to 100uA for hydrogen sulfide, and the both response time and recovery time were within 15 seconds.

• Applied Biological Chemistry
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• v.2
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• pp.9-14
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• 1961

The formation of sulfide from sulfate has been discussed from the thermodynamic principles. No mechanism of the reaction has been presented. From the stoichiometric and Nernst equations for the conversion of sulfate into sulfide, it was concluded that the formation of sulfide from sulfate can take place more readily if pH of a medium is low. The difficulty of this conversion increases with increasing pH. As pH of a medium increases, the degree of dissociation of H₂S into S= increases and this, in turn, renders the chance of precipitation of sulfide as FeS easier. Higher the pH of a soil or medium, greater is the S= concentration. The concentration of ferrous ion required to remove dissolved sulfide in a medium by forming insoluble FeS decreases with increasing pH. From the theory it was pointed out that an application of lime and iron rich foreign substances to a soil may be effective in causing the removal of dissolved sulfide from solution.

• Journal of Electrochemical Science and Technology
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• v.11 no.3
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• pp.248-256
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• 2020

In this study, pyrocatechol violet (Pcv) is proposed for the first time as an efficient electrocatalyst for oxidation of sulfide and flow injection analysis (FIA) of sulfide. A graphite pencil electrode (GPE) was modified with Pcv via immersion of the GPE into 0.01 M Pcv solution for 15 min. Cyclic voltammograms (CVs) demonstrated that Pcv/GPE exhibits a good electrocatalytic performance due to shift in the potential from +400 at bare GPE to +70 mV at Pcv/GPE and obtaining an enhancement in the peak current compared with the bare GPE. A linear range between 0.25 and 250 μM sulfide with a detection limit of 0.07 μM was obtained from the recorded current-time curves in Flow Injection Analysis (FIA) of sulfide. Sulfide in water samples was also successfully determined using the proposed FI amperometric methods.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.365.2-365.2
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• 2014

Nickel sulfide (NiS) has been utilized in optoelectronic applications, such as transformation-toughening agent for materials used in semiconductor applications, catalysts, and cathodic materials in rechargeable lithium batteries. Recently, high quality nickel sulfide thin films have been explored using ALD/CVD technique. Suitable precursors are needed to deposit thin films of inorganic materials. However, nickel sulfide precursors available for ALD/CVD process are very limited to nickel complexes with dithiocarbamate and alkanethiolate ligands. Therefore, it is essential to prepare novel nickel sulfide suitable for ALD/CVD precesses. Herein we report on the synthesis and characterization of new nickel sulfide complex with designed aminothiolate ligand. Furthermore thin films of NiS have been prepared on silicon oxide substrates by spin coating nickel precursor 10 wt% in THF. The novel complex has been characterized by means of 1H-NMR, elemental analysis, thermogravimetric analysis (TGA), X-ray Diffraction (XRD) and scanning electron microscope (SEM).