• Title/Summary/Keyword: sulfur-based

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Genetic Regulation of Corynebacterium glutamicum Metabolism

  • Wendisch Volker F.
    • Journal of Microbiology and Biotechnology
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    • v.16 no.7
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    • pp.999-1009
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    • 2006
  • Physiological, biochemical and genetic studies of Corynebacterium glutamicum, a workhorse of white biotechnology used for amino acid production, led to a waste knowledge mainly about amino acid biosynthetic pathways and the central carbon metabolism of this bacterium. Spurred by the availability of the genome sequence and of genome-based experimental methods such as DNA microarray analysis, research on genetic regulation came into focus. Recent progress on mechanisms of genetic regulation of the carbon, nitrogen, sulfur and phosphorus metabolism in C. glutamicum will be discussed.

The Effects of Desulfurization by Screen using Ca-based Absorbent in a Solid Waste Fluidized-bed Combustor (유동층연소로에서 제지공장 폐기물을 이용한 황산화물 제어시 스크린에 의한 탈황효과)

  • 조상원;이재홍;조기철;장상용;오광중
    • Journal of Environmental Science International
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    • v.7 no.6
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    • pp.783-791
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    • 1998
  • The objectives of this study were to investigate the characteristics of desulfurization under different experimental conditions and the effects of desulfurization bed fluidized bed combuster installed with the screen. The experimental results were as follows ; First, as the height of fluidized bed combustor becomes higher, the concentrations of $SO_2$ mainly increased and sulfur retion of paper sludge was higher than that of natural limestone. Second, the desulfurzation by natural limestone occurred at in-bed and the desulfurization by paper sludge occurred in the whole of fluidized bed combuster. In addition, we identified calcium sulfate by the analysis of SEM and XRD. Third, screen at splash region increased sulfur retention 2~5%, air velocity and anthracite fraction had a little effect on the sulfur retention.

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Effects of Air Pollution on Pinus thunbergii in Yocheon Industrial Comples (麗川工業 地의 大氣汚染이 곰솔에 미치는 影響)

  • 김태욱;이경재;김준선
    • Journal of Korean Society for Atmospheric Environment
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    • v.1 no.1
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    • pp.25-32
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    • 1985
  • To examine the effects of air pollution on Pinus thunbergii growing around Yocheon Industrial Complex, evaluation of visible injury based on Injury Index and chemical analysis of water-soluble sulfur and fluorine contents in needles were carried out on 30 sampling sites. Histological responses of needles were also investigated on the necrotic needle tissues. Not only Injury Index but water-soluble sulfur and fluorine contents were higher at all sites than those at control site, and showed significant correlationship among them. Especially, they were rather higher in the vicinity of air pollutants sources. Water-soluble sulfur contents were positively correlated with average atomospheric $SO_3$ concentrations. Microscopic examination of necrotic needle tissues showed that mesophyll cells were collapsed with hypertrophy and collapse of transfusion cells.

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Characteristics of Material Damage Caused by Acid Deposition in East Asia

  • Yoo, Young-Eok;Maeda, Yasuaki
    • Journal of Environmental Science International
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    • v.11 no.5
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    • pp.445-454
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    • 2002
  • Material exposure experiments were performed to evaluate the relationship between air pollution and material corrosion rates based on collaboration with researchers in China, Japan, and Korea. Qualitative and quantitative atmospheric corrosion was estimated from damage caused to bronze, copper, steel, marble, cedar, cypress, and lacquer plates exposed to outdoor and indoor conditions in certain East Asian cities. The effects of atmospheric and meteorological factors on the damage to the copper plates and marble pieces were estimated using a regression analysis. The results indicated that sulfur dioxide produced the most destruction of the materials, especially in South Korea and China. In Japan, the copper plates were damaged as a result of natural conditions and sea salt. Copper was also found to be damaged by the surface deposition of sulfur and chlorine. Meanwhile, marble was substantially degraded by gaseous sulfur dioxide, yet sulfate ions in rain had no effect. Accordingly, the analysis of air pollution from the perspective of material damage was determined to be very useful in evaluating and substantiating the intensity of air pollution in East Asia.

Novel Linking Ligand Containing Sulfur-Donor Atoms and Its Compounds of Palladium and Silver

  • Lee, Hee-K.;Lee, Soon-W.
    • Bulletin of the Korean Chemical Society
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    • v.28 no.3
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    • pp.421-426
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    • 2007
  • A linking ligand containing sulfur donor atoms in the terminal thiophene rings, 1,2-bis(thiophen-2-ylmethylene) hydrazine (L), was prepared by Schiff-base condensation. Ligand L reacted with [PdCl2(NCPh)2] to produce a molecular Pd compound [PdL2Cl2] (1). On the other hand, it reacted with AgNO3 and AgClO4 to produce a 2-D network [AgL0.5(NO3)] (2) and a 1-D polymer [AgL]ClO4 (3), respectively, whose structures are based on secondary intermolecular forces such as H-bonding, van der Waals interaction, and π-π stacking. Polymer 2 exhibited photoluminescence at room temperature in the solid state.

Impedance Properties of Lithium Sulfur Batteries (리튬황전지의 임피던스 특성)

  • Jin, Bo;Kim, Jong-Uk;Gu, Hal-Bon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.11a
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    • pp.444-447
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    • 2002
  • The Jig cells are fabricated in the drying room, and consisted of elemental sulfur used as a cathode active material, lithium metal used as a anode material and 1M $LiCF_{3}SO_{3}$ dissolved in TG (Tetraglyme)/DIOX (1,3-Dioxolane) used as a electrolyte. The four kinds of electrolytes with different content of TG and DIOX are prepared. The electrochemical properties of the foregoing electrolytes-based lithium sulfur batteries are analyzed by AC impedance experiments. The conductivity of four different electrolytes is investigated. The conductivity of electrolyte [1M $LiCF_3SO_3$ dissolved in TG/DIOX (50:50, vol.)] is higher than that of other three kinds of electrolytes with different volume ratio (70:30, 30:70) and single solvent (TG).

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Volatile Flavor Components of Leek(Allium tuberosum Rottler) (부추(Allium tuberosum Rottler)의 휘발성 향기성분)

  • 김경수;박은령;조정옥;김선민;이명렬
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.4
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    • pp.563-567
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    • 1998
  • Volatile flavor components of edible portion of leek(Allium tuberosum R.) were extracted by SDE(simultaneous steam distillation and extraction) method using the mixture of n-pentane and diethylether (1 : 1, v/v) as an extract solvent and analyzed by GC-FID and GC/MS. Identification of the volatile flavor components was mostly based on the RI of GC and mass spectrum of GC/MS. A total of sixty-five components from leek extract were classified as 28 sulfur-containing compounds, 12 aldehydes, 9 alcohols, 4 lactones and esters, 3 acids and hydrocarbons, and 2 miscellaneous compouds. The sulfur-containing compounds were predominant in leek extract. Dimethyl disulfide(19.47%) and dimethyl trisulfide(17.38%) were the main compounds and trans-1-propenyl methyl disulfide, trans-2-hexenal and methyl allyl disulfide were also detected large amounts in leek.

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Odor generation pattern of swine manure according to the processing form of feed

  • Won Choi;Wooje Lee;Kiyoun Kim
    • Journal of Animal Science and Technology
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    • v.66 no.1
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    • pp.219-231
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    • 2024
  • Feed has a great influence on the composition of swine manure, which is the principal cause of odor. Therefore, the purpose of this study is to simply change the shape of pig feed and control calories to find a suitable feed form for reducing the smell of swine manure. The experiment was conducted on 15 pigs from July to August 2021, and a total of three measurements were done. Three types of feed were evaluated in this study. The analysis items related to odor of swine manure are complex odor, ammonia, sulfur-based odors, and volatile organic compounds (VOCs). In the case of complex odor, dilution multiples tended to decrease over time, except for type A feed. The concentration of ammonia in all types of feed decreased over time. Most sulfur-based odorous substances except hydrogen sulfide at the first measurement were not detected. Representatively, Decane, 2,6-Dimethylnonane, and 1-Methyl-3-propylcycolhexane were detected in VOCs generated from swine manure. The major odorous substansces in swine manure have changed from ammonia and sulfur compounds to VOCs. In order to reduce the odor caused by swine manure, it is ad-vantageous to use low-calorie feed consisting of pellet-type.

The Effect of ZnO Content on the Performance of Spray-dried Zn-based Desulfurization Sorbent for H2 Cleanup (황화수소 정제용 아연계 분무건조 탈황제의 활성성분 함량 변경에 따른 물성 및 반응 특성)

  • Baek, Jeom In;Eom, Tae Hyoung;Lee, Joong Beom;Jegarl, Seong;Ryu, Chong Kul
    • Transactions of the Korean hydrogen and new energy society
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    • v.25 no.5
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    • pp.482-490
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    • 2014
  • Gaseous sulfur compound such as $H_2S$ or COS in coal- or biomass-derived hot syngas can be purified by solid sorbents at high temperatures. In this study, we investigated the physical properties and reactivity of solid regenerable desulfurization sorbents with 37.2, 41.9, and 46.5wt% ZnO to look into the ZnO content effect. The sorbents were produced by spray-drying method to apply to a fluidized-bed process. Sulfidation and regeneration reaction were carried out using a thermogravimetric analyzer. Sorbent prepared with 46.5wt% ZnO had physical properties suitable for a fluidized-bed process applications such as spherical shape, sufficient mechanical strength and density, high porosity and surface area. It showed high sulfur sorption capacity of 10.4wt% (ZnO utilization of 57%) at reaction temperatures of 500 and $650^{\circ}C$ for sulfidation and regeneration, respectively. However, the sulfur sorption capacity and ZnO utilization were significantly reduced and dimple shape appeared when the ZnO content decreased to 37.2 and 41.9wt%. Sulfur sorption capacity and regenerability were improved as reaction temperature increased within the experimental temperatures used in this work. The reaction temperature zones of $1500{\sim}550^{\circ}C$ and $650{\sim}700^{\circ}C$ are recommended for sulfidation and regeneration, respectively, to lead best reaction performances of the ZnO-based spray-dried sorbents developed in this work.