• Title/Summary/Keyword: sulfur

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Experimental Study on Development of Artificial Fishing Reefs Using Environment-Friendly Sulfur Concrete (환경친화적인 유황콘크리트 인공어초 개발을 위한 실험적 연구)

  • Park, Sung-Bae;Kim, Seok-Chel;Kim, Kyoung-Hoon;Hong, Chong-Hyun
    • Journal of Ocean Engineering and Technology
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    • v.21 no.3 s.76
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    • pp.58-64
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    • 2007
  • New artificial fishing reefs are developed using modified sulfur concrete. Modified sulfur concrete, which is made of by-product aggregates and modified sulfur binder, has good properties, including high density, less water absorption, high strength, high salt resistance, and good affinity for living organisms. This paper shows the mechanical properties of modified sulfur concrete and its field tests under the sea. We have found that the pH-neutral materials attach microalgae and seaweed more readily, compared to the pH-high materials.

Influence of Air Void Characteristic on Chloride Diffusion Coefficient and Compressive Strength of Concrete using Urea and Sulfur (요소와 유황을 첨가한 콘크리트의 압축강도와 염화물 확산계수에 대한 공극특성의 영향)

  • Kim, Jae Hyun;Hong, Ki Nam;Jeon, Byeong Gu
    • Journal of the Korean Society of Safety
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    • v.31 no.4
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    • pp.75-81
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    • 2016
  • This study presents the effect of urea and sulfur admixture on compressive strength, chloride diffusion coefficient, and internal void distribution of concrete. Compressive strength of concretes with urea admixture by 5% increased by 5% relative to Control. However, that of concretes with urea admixture over 10% decreased. Chloride diffusion coefficient of concrete with urea and sulfur admixture decreased by 40% relative to Control. Additionally, the volume of internal void of concrete with urea and sulfur admixture decreased by 20% relative to Control. Therefore, it can be mentioned from test results that the use of adequate urea and sulfur admixture improves the mechanical properties and durability of concrete.

A Relationship Between AtmosPheric $SO_{2}$ Concentrations and Water Soluble Sulfur Contents in Gingko biloba in Seoul (서울 일부지역의 도로변 대기중 $SO_{2}$ 농도와 은행나무잎의 수용성 황함량과의 관계)

  • 박정숙;정문식;박석환
    • Journal of Environmental Health Sciences
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    • v.17 no.1
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    • pp.1-12
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    • 1991
  • The atmospheric SO$_{2}$ concentrations and water soluble sulfur contents in Ginkgo biloba were measured and analyzed in auto-measuring station, Kwangleung, and Yongmun from August 5 to October 21, 1990. The results of the study are as follows: 1. Atmospheric SO$_{2}$ concentrations between the seoul area(Pulkwang, Ssangmun, Myonmok, Oilurn) in which the concentrations exceeded the air quality standards and the surburb of seoul (Kwangleung, Yongmun) revealed the significant difference (p<0.01). 2. Water soluble sulfur contents in Ginkgo biloba in autumn were higher than those in Ginkgo biloba in summer (p<0.01). Water soluble sulfur contents in leaves showed a significant difference between seoul and its surburb(p<0.01). 3. Correlation between atmospheric SO$_{2}$ concentration and water soluble sulfur content of Ginkgo biloba in autumn was as follow Y=0.2714+9.8123 X, r=0.6362 (X: Airborne SO${_2}$ Concentration according to sampling location, Y: Water Soluble Sulfur Contents)

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Study on electrochemical performances of sulfur-containing graphene nanosheets electrodes for lithium-sulfur cells

  • Son, Ki-Soo;Kim, Seok
    • Carbon letters
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    • v.15 no.2
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    • pp.113-116
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    • 2014
  • Due to their morphology, electrochemical stability, and function as a conducting carbon matrix, graphene nanosheets (GNS) have been studied for their potential roles in improving the performance of sulfur cathodes. In this study, a GNS/sulfur (GNS/S) composite was prepared using the infiltration method with organic solvent. The structure, morphology and crystallinity of the composites were examined using scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The electrochemical properties were also characterized using cyclic voltammetry (CV). The CV data revealed that the GNS/S composites exhibited enhanced specific-current density and ~10% higher capacity, in comparison with the S-containing, activated-carbon samples. The composite electrode also showed better cycling performance for multiple charge/discharge cycles. The improvement in the capacity and cycling stability of the GNS/S composite electrode is probably related to the fact that the graphene in the composite improves conductivity and that the graphene is well dispersed in the composites.

Studies on Gold Balsam (금발삼에 관한 연구)

  • 박용완;김충일
    • Journal of the Korean Ceramic Society
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    • v.11 no.4
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    • pp.31-36
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    • 1974
  • For gold balsam, the suitable sulfur balsam which is made of lavender oil and sulfur is found to be the distillate with the content of 15~19% sulfur. The sulfur balsam is distillated under 20mmHg vaccum at 84~105$^{\circ}C$. The composition of the compound which is produced by reaction between sulfur balsam and gold chloride is recognized as C10H18SAuCl3. This varys to C10H18SAuCl in water. The reaction constants K from C10H18SAuCl3 to C10H18SAuCl at 30, 40, 5$0^{\circ}C$ are as followsr. K1=7.97~9.28$\times$10-2 K2=2.81~3.79$\times$10-1 K3=4.74~6.74$\times$10-1 The plots of T versus log K are linear, which shows pseudo-first order reaction. The lower temperature is, the more stable C10H18SAuCl3 is. The gold balsam with excess sulfur balsam is increased in stability.

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Studies on the determination of atmospheric sulfur dioxide and elimination of sulfur in kerosene by thiobacilli (미생물에 의한 공기의 SO$_{2}$ 오염방제에 관한 연구)

  • 이배함;이병조;이정근;정성구
    • Korean Journal of Microbiology
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    • v.7 no.2
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    • pp.57-62
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    • 1969
  • The experiments attempted to basic studies on the atmospheric dioxide in Korea and on the elimination of sulfur in oil Thiobacilli in order to control of atmospheric sulfur dioxide. The results of experiments are following as : 1) Content of atmospheric sulfur dioxide in industrial zone which used kerosene for fuel was 0.092 ppm(average) and 0.16ppm(maximum). 2) Content of sulfur dioxide at room air which used briquet for stove fire was 0.44ppm (average) adn 0.50 pp,(maximum). 3) Thirteen strains of thiobacilli were isolated from Korean soil and sewage and they were identified with T. thiooxidans (5strains), T. thioparus(3strains), T.ferrooxidans 3 man's observation and the description in Bergey's manual. 4) Two promising strains, one of T. thiooxidans and one of T. ferooxidans. were selected for elimieation of in kerosene.

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Strength Properties of the Mortar According to the Curing Condition of the Modified Sulfur Mortar (개질유황 모르타르의 양생조건에 따른 모르타르의 강도특성)

  • Jung, Byeong-Yeol;Lee, Sang-Soo;Song, Ha-Young
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2013.05a
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    • pp.332-333
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    • 2013
  • This research utilizes the modified sulfur having the low melting point which 65℃ is tries to study the strength property of the mortar according to the cure method of the modified sulfur mortar. And we try to use as basic data for investigating the curing condition of the light panel optimum utilizing the modified sulfur. We experimented by five kinds; 20℃ water curing method and 20, 40, 60, 80(℃) air dry curing method. In 3 day curing, the compressive strength was improved caused by high curing temperature. But the compressive strength was degraded caused by enhanced temperature in 7day curing and 28day curing. Therefore, the curing temperature of the modified sulfur mortar is determined that it comes 20 time case curing and the water curing is the most recommendable.

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Effect of the alkyl sulfates to starilization of colloidal sulfurs containe in white lotion (Fatty alkyl sulfate 가 colloidal sulfur 의 안정성(安定性)에 미치는 영향)

  • Kim, Johng-Kap;Lee, Sook-Kyung
    • Journal of Pharmaceutical Investigation
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    • v.4 no.4
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    • pp.38-45
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    • 1974
  • Sulfur had been used for the medical fields as fungacidal bacteriocides and gelatolytic agent from ancient B. C 700, their prepartiones contained the sulfur are restrict to freely medication, the restrutive reasones are the it's preparation stabilized sparing solubility, and limit to pharmaceutical development of colloidal sulfur-self. Anthors prepared white lotion, registered on U.S.P XIII from the colloidal sulfur, by the method midified buku zawa make the stabilized lotion by the various fatty alkyl sulfates, and the result obtained are as follows the suspending agents for stabilize to the colloidal sulfur are the fatty alcohol sulfates than natural clay on the imbibition appeareuce and usefulnss. The adequate quantities of stearic acid in lotion base are $1.5{\sim}2.0$ percent for refluidity and pourability. The carbon numbers in alkyl radical used fatty alcohol sulfates as anionic surfactants are maxture of $12{\sim}18$ about efficiency, as possible as, the electrolyte is removed from the white lotion.

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Viscosity and Thermodynamic Properties of Liquid Sulfur

  • Chang, Man-Chai;Jhon, Mu-Shik
    • Bulletin of the Korean Chemical Society
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    • v.3 no.4
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    • pp.133-139
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    • 1982
  • It has been presumed that the molten sulfur above $159^{\circ}C$ consists of an equilibrium mixture of $S_8$ rings and $S_x$ polymers where the number average degree of polymerization, P, is large. But it is known that admixture of halogens with liquid sulfur greatly reduce the viscosity. Constructing a new equilibrium equation, it is possible to evaluate the viscosity when halogens are added to liquid sulfur. Calculated viscosity is in good agreement with experimental values. Using the proposed model, the thermodynamic properties of liquid sulfur are also calculated over a wide range of temperature which the sulfur exists as the polymer.

Chemistry of Carbonate-Sulfur Flux

  • Q. Won Choi;Choi Han;Chang So-Young;Pyun Chong-Hong;Kim Chang-Hong
    • Bulletin of the Korean Chemical Society
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    • v.15 no.12
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    • pp.1118-1121
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    • 1994
  • Reactions of alkaline metal carbonates with sulfur are investigated in detail. The evolution of CO and a trace of $SO_2$ were observed in the course of reaction with major component of polysulfides. Some evidences that the reaction proceeds with breaking of terminal sulfur-sulfur bond in the sulfur polymer, and forming CO, $SO_2$ and polysulfide are presented. Polysulfides have the role of keeping free sulfur and allow it to react with other chemicals to rather high temperatures.plexes, whereas the binuclear and mononuclear complexes of Mn$^{2+}$ and Co$^{2+}$