• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.376-382
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• 2014

The soluble loess-sulfur mixture allowed standing to remove insoluble component materials for five weeks after manufacturing. We decreased the pH level of soluble loess-sulfur mixture at pH 1.0 modified with decreasing 25% sodium hydroxide than original content. The pH ranges of soluble loess-sulfur mixture solutions were adjusted to pH 5.0-pH 11.0 (pH 1 unit) with brown rice vinegar (pH 2.8). The pH of original loess-sulfur mixture was about pH 13 and damaged the foliar parts and young leaves of tomato after twice application. These stock solutions can be diluted 500:1 with tap water to make a 0.05% working solution and were sprayed two times with 7 days interval to the leaf and stem of tomato, which were spontaneously infected with E. cichoracearum. Control efficacy of powdery mildew ranged from 85% to 90% at 7 days after first application. After second application, each loess-sulfur mixture solutions adjusted pH level significantly suppressed the powdery mildew disease in tomato. Consequently, loess-sulfur complex adjusted pH level with brown rice vinegar was suggested to be low in acute toxicity at all different pH values and suggested to use an agent for control of tomato powdery mildew in organic farming.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.2
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• pp.155-160
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• 2005

Removal of methyl mercaptan was investigated using adsorption on virgin activated carbon (VAC) and modified activated carbons with acidic chemicals in the present work. CAC, NAC, AAC and SAC were represented as activated carbons modified with HCI, HNO$_{3}$, CH$_{3}$COOH and H$_{2}$S0$_{4}$ ,respectively The pore structures were evaluated using nitrogen isotherm. The surface properties of virgin activated carbon and modified activated carbons were characterized by EA, pH of carbon surface and acid value from Boehm titration. The modification of activated carbon with acidic chemicals resulted in a decrease in BET surface area, micropore volume and surface pH, but an increase in acid value. The order of the adsorption capacity of activated carbons was NAC>AAC>SAC>CAC>VAC, and in agreement with that of acid value of activated carbons, whereas in disagreement with that of micropore volume of activated carbons. It appeared that chemical adsorption played an important role in methyl mercaptan on modified activated carbons with acidic chemicals compared to virgin activated carbon. Modifying activated carbon with acidic chemicals enabled to significantly enhance removal of methyl mercaptan.

• Elastomers and Composites
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• v.22 no.4
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• pp.314-323
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• 1987

A blend ratio of rubber vulcanzates comprising NBR, CR, EPDM, NR, BR, and SBR alone or blended is determind through a P.G.C. It is found that a characteristic peak of elastomer is proportional to the content of each elastomer when they are pyrolysed. It is also classified to the different AN content in NBR vulcanizates, identification of sulfur-modified and non-sulfur bearing CR polymers, and the content of ethylene, propylene monomer and the third monomer in EPDM vulcanizetes.

• Journal of Environmental Science International
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• v.22 no.8
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• pp.1019-1027
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• 2013

Sulfur hexa-fluoride has been used as a etching gas in semiconductor industry. From the globally environmental issues, it is urgent to control the emissions of this significant greenhouse gas. The main objective of this experimental investigation was to find the effective catalyst for $SF_6$ decomposition. The precursor catalyst of hexa-aluminate was prepared to investigate the catalytic activity and stability. The precursor catalyst of hexa-aluminate was modified with Ni to enhance the catalytic activities and stability. The catalytic activity for $SF_6$ decomposition increased by the addition of Ni and maximized at 6wt% addition of Ni. The addition of 6wt% Ni in precursor catalyst of hexa-aluminate improved the resistant to the HF and reduced the crystallization and phase transition of catalyst.

• Bulletin of the Korean Chemical Society
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• v.6 no.1
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• pp.29-32
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• 1985

Normal modes of crystalline orthorhombic sulfur belonging to the space group $D_{2h}$-Fddd, have been evaluated by taking the lowest temperature phase in the solid. Normal modes are obtained by the valence force field with modified force constants and a quantitative description of the mode is adjusted by the potential energy distribution. Since the full crystal system of orthorhombic sulfur is so large, we intended to calculate the normal modes simply by constructing the imaginary box made by the infinite mass boundary. And the Raman experiment is done by using the more powerful Ar-Kr gas laser with lowering the temperature to ${\sim}10^{\circ}K$.

• Journal of Environmental Impact Assessment
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• v.7 no.2
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• pp.71-82
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• 1998

This study focuses on one of the most typical energy-intensive industries, the steel industry. The two-fold purpose of the study is to develop a model to assess measures to alleviate sulfur dioxide($SO_2$) emissions from the steel industry and to propose a concrete $SO_2$ emission reduction measure from the steel industry. This study partially employed and modified AIM(Asia-Pacific Integrated Model) developed by Japan National Environmental Research Institute to develop AIM/KOREA SULFUR model for simulation. In the study, a base scenario, which is BAU(Business As Usual) scenario, and mitigation scenarios(a use of low-sulfur contain fuel, fuel conversion to cleaner energy, an induction of desulfurization systems, and energy saving) were employed. The results of the simulation are summarized below: The sulphur dioxide emission from the steel industry in 1992 was estimated to be 252,000 metric tons; however, according to BAU scenario, sulphur dioxide emission is expected to be increased to 586,000 metric tons, which is 2.3 times greater than that in 1992 by year 2020. To alleviate such increasement, simulation results under various 7scenarios proved that some degrees of reduction may be possible by an induction of desulfurization systems although there may be numerous ways to interpretate the simulation results; however, the bottom line is that it appears to be difficult to achieve the Korean Ministry of Environment's policy goal-a mitigation of sulphur dioxide concentration to 0.01ppm.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.3
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• pp.489-495
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• 2011

The purpose of this study was to analyze harmful heavy metals, sulfur dioxide and residual pesticides in 30 kinds of oriental medical materials. This study was carried out on 30 samples of oriental medical materials. The examination's methods fallow the guideline of Food and Drug Administration. Inductively Coupled Plasma Mass Spectrometer (ICP-OES) was used to analyze lead, arsenic, cadmium. Mercury was analyzed by amalgamation method. A modified Monier-Williams method was used to analyze sulfur dioxide. The Gas Chromatography / Electron Capture Detector (GC/ECD) was used to analyze residual pesticides. Most of the results were within normal limits at baseline. but Cadmium was detected 0.523 mg/kg more than 0.3 mg/kg in Cinnamomi ramulus and Endosulfan was detected 11.595 mg/kg more than 0.2 mg/kg in Alismatis rhizoma. We needs to keep the quality of herbal medicines assessing and controling for safety of herbal medicines.

• Journal of the Korean Wood Science and Technology
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• v.11 no.3
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• pp.3-13
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• 1983

Fiber mats were made at five density levels, using fibers from kraft pulp screening rejects, rice straw and a 50/50 mixture of the two. They were soaked in the sulfur compounds. Specimens cut from the composite panels were tested in flexure at time intervals for one year to study the effect of aging. Modulus of elasticity (MOE) and modulus of rupture (MOR) were determined. Under optimum conditions of fiber mat preparation and saturation with molten sulfur and modified sulfur, composites were produced which exhibited mechanical properties comparable to conventional fiberglass in some properties and superior to conventional wood-based composition boards, For example. the moduli of elasticity of the reinforced composites made from pulp screening rejects, with a density of 0.35 gm/$cm^3$, were greater than 1,000,000 psi as compared 800.000 psi for high-density hardboard (1.28 gm/$cm^3$). Modulus of rupture of the best reinforced composites was about 7,000 psi, comparable to 6,000 psi of high-density hardboard.

• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.435-447
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• 2011

This study was investigated to determine the contents of sulfur dioxide residues in medicinal herbs in Seoul Yang Nyoung Shi in 2010 (1,522 samples of 189 kinds). Samples were measured by modified Monier-Williams method. of the total samples, 618 samples (84 kinds) were domestic, and 904 samples (158 kinds) were imported. The content of sulfur dioxide in the domestics showed the range of 0.0 to 1,298.0 mg/kg (average 12.7 mg/kg), while those in imported samples were the range of 0.0 to 3,982.2 mg/kg (average 42.4 mg/kg). The average (mg/kg) amount of sulfur dioxide by parts in medicinal herbs was as follows; Tuber 122.3, Radix 69.3, Rhizoma 37.4, Cortex 33.3, Fructus 8.8, Ramulus 4.9, Semen 4.6, Folium 3.4, Flos 2.7, Perithecium 1.4. of the total samples (1,522), 52 samples (3.4%) were violated the KFDA regulatory guidance of sulfur dioxide. Among these 52 unsuitable samples, 16 samples (7 kinds) were domestic, and 36 samples (23 kinds) were imported. Approximately 88.1% of the total samples was less than 10 mg/kg of sulfur dioxide and 6.3% of the total samples showed more than 30 mg/kg of sulfur dioxide.

• Journal of the korean academy of Pediatric Dentistry
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• v.51 no.2
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• pp.149-164
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• 2024

This study compared the solubility, water absorption, dimensional stability, release of various ions (hydroxyl, calcium, sulfur, strontium, and silicon), and cytotoxicity of light-cured resin-modified pulp-capping materials. Resin-modified calcium hydroxide (Ultra-blend^TM plus, UBP), light-cured resin-modified calcium silicate (TheraCal LC^TM, TLC), and dual-cure resin-modified calcium silicate (TheraCal PT^TM, TPT) were used. Each material was polymerized; solubility, 24-hour water absorption, and 30- day dimensional stability experiments were conducted to test its physical properties. Solubility was assessed according to the ISO 6876 standard, and 24 hours of water absorption, 30 days of dimensional stability were assessed by referring to the previous protocol respectively. Eluates at 3 and 24 hours and on 7, 14, and 28 days were analyzed according to the ISO 10993-12 standard. And the pH, Ion-releasing ability, cell proliferation rate, and cell viability were assessed using the eluates to evaluate biochemical characteristics. pH was measured with a pH meter and Ion-releasing ability was assessed using inductively coupled plasma atomic emission spectrometry (ICP-AES). Cell proliferation rate and cell viability were assessed using human dental pulp cells (hDPCs). The former was assessed by an absorbance assay using the CCK-8 solution, and the latter was assessed by Live and Dead staining. TPT exhibited lower solubility and water absorption than TLC. UBP and TPT demonstrated higher stability than TLC. The release of sulfur, strontium, calcium, and hydroxyl ions was higher for TLC and TPT than for UBP. The 28-day release of hydroxyl and silicon ions was similar for TLC and TPT. TLC alone exhibited a lower cell proliferation rate compared to the control group at a dilution ratio of 1 : 2 in cell proliferation and dead cells from Live and Dead assay evaluation. Thus, when using light-cure resin-modified pulp-capping materials, calcium silicate-based materials can be considered alternatives to calcium hydroxide-based materials. Moreover, when comparing physical and biochemical properties, TPT could be prioritized over TLC as the first choice.