• Journal of the Korean Ceramic Society
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• v.11 no.1
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• pp.29-35
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• 1974

Effect of calcium sulfate and barium sulfate on the formation of portland cement clinker was studied by means of chemical analysis. DTA and X-ray diffraction analysis. In the presence of liquid phase, effect of the additives on the formation of tricalcium silicate was examined according to the reaction, 2CaO.$SiO_3$＋CaO$\longrightarrow$3CaO.$SiO_3$, which is the principal reaction in portland cement clinkerization, and optimum conditions in firing clinker concerning amount of additive, firing time and temperature were determined, and its kinetics was referred to. The experimental results are summerized as follow: (1) Appropriate burning temperature range of cement clinker is more limited as the content of calcium sulfate in clinker is increased. Amount of calcium sulfate, firing time and temperature in proper condition of clinkerization is related to each others. Being added suitable quantity of calcium sulfate, firing temperature of clinker can be lowered about $100^{\circ}C$. (2) When 3-5 mole% of calcium sulfate is added, firing time of 15-30 minutes at about $1380^{\circ}C$ is reasonable, and if the content is over7 mole %, firing for 1 hr. or more at $1350^{\circ}C$ is anticipated to be optimum condition. (3) In the reaction of tricalcium silicate formation, the role of barium sulfate as a mineralizer is similar to that of calcium sulfate, but the optimum firing temperature of cement clinker containing barium sulfate tends to be 20-$30^{\circ}C$ higher than that of clinker containing calcium sulfate. (4) When barium sulfate is used as mineralizer, 2-3 mole % of it to tricalcium silicate is recommended and if it is added more than this amount, free CaO is increased rapidly in clinker and alite formation is inhibited.

• Journal of Bio-Environment Control
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• v.7 no.1
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• pp.55-61
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• 1998

This experiment was conducted to evaluate the effects of sulfate ion concentration in nutrient solution on the growth and qualify of Mongolian wormwood (Artemisia mongolica var. tenuifolia). Sulfate ion concentration was treated 0, 0.5, 1, 2 and 3mM using the modified nutrient solution composition for herb plants developed by European Vegetable R & D Center in Belgium. The growth of Mongolian wormwood was good at 3mM treatment and dry weight was best at 3mM treatment, Chlorophyll content increased with sulfate ion concentration. Mineral content did not show any significant difference among treatments. But Ca content in tissue markedly decreased at 3mM treatment. Sulfate ion uptake increased in proportion to sulfate ion concentration in nutreint solution, the higher sulfate ion concentration, the more uptake of sulfate ion by plant. At 1mM sulfate ion treatment, essential oil content was best, but the higher sulfate ion concentration resulted in decrease of essential oil content.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.615-621
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• 2010

The viability of low-temperature sulfate reduction with hydrogen as electron donor was studied with a bench-scale gas-lift bioreactor (GLB) operated at $9^{\circ}C$. Prior to the GLB experiment, the temperature range of sulfate reduction of the inoculum was assayed. The results of the temperature gradient assay indicated that the inoculum was a psychrotolerant mesophilic enrichment culture that had an optimal temperature for sulfate reduction of $31^{\circ}C$, and minimum and maximum temperatures of $7^{\circ}C$ and $41^{\circ}C$, respectively. In the GLB experiment at $9^{\circ}C$, a sulfate reduction rate of 500-600 mg $l^{-1}d^{-1}$, corresponding to a specific activity of 173 mg ${SO_4}^{2-}g\;VSS^{-1}d^{-1}$, was obtained. The electron flow from the consumed $H_2$-gas to sulfate reduction varied between 27% and 52%, whereas the electron flow to acetate production decreased steadily from 15% to 5%. No methane was produced. Acetate was produced from $CO_2$ and $H_2$ by homoacetogenic bacteria. Acetate supported the growth of some heterotrophic sulfate-reducing bacteria. The sulfate reduction rate in the GLB was limited by the slow biomass growth rate at $9^{\circ}C$ and low biomass retention in the reactor. Nevertheless, this study demonstrated the potential sulfate reduction rate of psychrotolerant sulfate-reducing mesophiles at suboptimal temperature.

• Journal of Microbiology and Biotechnology
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• v.18 no.11
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• pp.1809-1818
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• 2008

Biotechnological treatment of sulfate- and metal-ions-containing acidic wastewaters from mining and metallurgical activities utilizes sulfate-reducing bacteria to produce sulfide that can subsequently precipitate metal ions. Reducing sulfate at a low pH has several advantages above neutrophilic sulfate reduction. This study describes the effect of sulfide removal on the reactor performance and microbial community in a high-rate sulfidogenic gas-lift bioreactor fed with hydrogen at a controlled internal pH of 5. Under sulfide removal conditions, 99% of the sulfate was converted at a hydraulic retention time of 24 h, reaching a volumetric activity as high as 51 mmol sulfate/l/d. Under nonsulfide removal conditions, <25% of the sulfate was converted at a hydraulic retention time of 24 h reaching volumetric activities of <13 mmol sulfate/l/d. The absence of sulfide removal at a hydraulic retention time of 24 h resulted in an average $H_2S$ concentration of 18.2 mM (584 mg S/I). The incomplete sulfate removal was probably due to sulfide inhibition. Molecular phylogenetic analysis identified 11 separate 16S rRNA bands under sulfide stripping conditions, whereas under nonsulfide removal conditions only 4 separate 16S rRNA bands were found. This shows that a less diverse population was found in the presence of a high sulfide concentration.

• Journal of Environmental Science International
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• v.25 no.5
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• pp.645-654
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• 2016

For the purpose of reuse the wasted by-products from the skate process to the health functional food or medicinal material, chondroitin sulfate was extracted from the skate cartilage with the method of hydrolysis with protease enzyme, and the contents of chondroitin sulfate and hydrolyzed protein were measured qualitatively and quantitatively. The effects of chondroitin sulfate on body weight or liver weight changes, hepatotoxicity elimination and anti-inflammatory actions were measured from in vivo test with feed-treated mice. From the hydrolytic extraction of skate cartilage with the mixture of 1% alcalase and 1% protease for 4 hours, the extraction yield of chondroitin sulfate was about 32.55%. The content and molecular weight of chondroitin sulfate was 26.63% and $2.85{\times}10^5Da$., respectively and the content ratio of chondroitin sulfate to protein was measured to 1 to 2.76 with gel permeation chromatography. For the odor component, trimethylamine decreased about 30% but almost not ammonia from chondroitin sulfate with the treatment of activated carbon. From the feeding chondroitin sulfate to mice, the control effect of body and liver weights decrease was measured, anti-inflammatory action and hepatotoxicity elimination action were also measured. From these results, process operation conditions for manufacturing of chondroitin sulfate were suggested.

• Molecules and Cells
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• v.26 no.5
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• pp.415-426
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• 2008

The interactions between the host and microbial pathogen largely dictate the onset, progression, and outcome of infectious diseases. Pathogens subvert host components to promote their pathogenesis and, among these, cell surface heparan sulfate proteoglycans are exploited by many pathogens for their initial attachment and subsequent cellular entry. The ability to interact with heparan sulfate proteoglycans is widespread among viruses, bacteria, and parasites. Certain pathogens also use heparan sulfate proteoglycans to evade host defense mechanisms. These findings suggest that heparan sulfate proteoglycans are critical in microbial pathogenesis, and that heparan sulfate proteoglycan-pathogen interactions are potential targets for novel prophylactic and therapeutic approaches.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.425-428
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• 2000

When concrete structures are exposed to sulfate or marin environments, sulfate ions penetrated into concrete make it deteriorate. An accelerated test under potential difference method was performed to evaluate not only the sulfate ion diffusivity in ordinary portland cement and ground granulated blast-furnace slag cement concretes but the effect of slag replacement and water-cement ratio on the sulfate ions diffusivity. As the result of this study, we assumed the sulfate ion diffusivity was significantly related with total passed charge and initial current in concrete. Moreover sulfate ions penetration resistance of ordinary portland cement concrete was superior to that of ground granulated blast-furnace slag cement concrete.

• Journal of the Korean Ceramic Society
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• v.11 no.2
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• pp.17-21
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• 1974

Miscibility of barium sulfate in tricalcium silicate was investigated by firing 3CaCO3·SiO2 mixture containing barium sulfate at 1530℃. Added amount of barium sulfate to the mixture was zero to 5 mole % with intervals of 1 mole %. Lattice parametres were also calculated. Results were as follow; 1) Dissolution of barium sulfate in tricalcium silicate does not alter the symmetry in room temperature, but influences it's polymorphic transition forms, temperatures and thermal effects; modification triclinic Ⅱ is stabilized in room temperature. 2) Barium sulfate dissolves about up to 2 mole % in tricalcium silicate and more than this amount, tricalcium silicate formation is inhibited. 3) Unit cell volume of tricalcium silicate is slightly decreased with dissolution of barium sulfate, mainly because of contraction in c axis.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.704-709
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• 2000

This study is to test effects of sulfate attack on deterioration of cement mortar. Four tests have been carried out with four types of mortars mixed by ordinary portland cement and sulfate-resistant portland cement containing blast-furnace slag and fly-ash. It was immersed in sulfate solution for 7, 28, 91, and 180 days. from the test results, sulfate attack resistance of cement mortar was improved by admixtures (blast-furnace slag and fly-ash), sulfate-resistance portland cement mortar showed high resistance than ordinarily portland cement at compressive strength, and similar the resistance of sulfate attack with ordinarily portland cement mortar with admixtures.

• Journal of Pharmaceutical Investigation
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• v.4 no.1_2
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• pp.19-24
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• 1974

The comparative studies were made on the analgesic antipyretic effects of aminopyrine used individually and combined with parasympathetic agents (atropine sulfate). The analgesic antipyretic effects were eximined by Writhing's method to the experimental groups(mouse), and the following effects were found : 1) The active intensity of aminopyrine by it's oral administration combined with atropine sulfate is as follows. Amiinopyrine 80 mg/kg combided with Atropine sulfate 0.005 mg/kg=Aminopyrine 100 mg/kg 2) The most active range of intensity of Atropine sulfate(adjuvant) by it's oral administration is as follows. Atropine sulfate $0.004{\sim}0.005\;mg/kg$.