• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.645-652
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• 1996

Selective catalytic oxidation of $H_2S$ to elemental sulfur using $TiO_2/SiO_2$ catalysts was investigated in this study. The reaction test with pure $TiS_2$ and $Ti(SO_4)_2$ and cyclic temperature operation revealed that $TiO_2$ had a good resistance to sulfation and sulfidation, which are known as the main cause of catalytic deactivation in sulfur recovery process. With the increase of $TiO_2$ loading amount in $TiO_2/SiO_2$ catalysts, the conversion of $H_2S$ increased and the selectivity of elemental sulfur was very slightly decreased. As the ratio of $O_2/H_2S$ increased, the selectivity to elemental sulfur was drastically decreased. In the presence of 10 vol.% water vapor to a stoichiometric mixture of $H_2S$ and $O_2$($H_2S$= 5 vol.% O=2.5 vol.% ), both activity and selectivity of 10 wt.% $TiO_2/SiO_2$ catalyst are decreased, but it still showed more than 80% of sulfur yield.

• Resources Recycling
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• v.14 no.6 s.68
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• pp.3-9
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• 2005

In this study, the separation and recovery of cerium hydroxide was investigated from the wasted cerium polishing powders. Waste cerium polishing powder contains $64.5\;wt\%$ of rare earth oxide and the content of cerium oxide is $36.5\;wt\%$. Since cerium oxide, $56.3\%$ of rare earths, is the most stable state in rare earth, the dissolution of cerium oxide in acid solution is not easy. Therefore the process of rare earth oxide by sulfation and water leaching was examined in order to increase the recovery of rare earth. Rare earth elements were recovered in the form of $\Re{\cdot}Na(SO_{4})_{2}$ by the addition of sodium sulfate to leached solution. The slurry of rare earth hydroxide was prepared by the addition of $\Re{\cdot}Na(SO_{4})_{2}$ to sodium hydroxide solution. After the oxidation of cerous hydroxide($CE(OH)_{3}$) to ceric hydroxide($CE(OH)_{3}$) by aeration, ceric hydroxide was separated from other rare earth hydroxides by controlling the acidity of solution.

• Archives of Pharmacal Research
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• v.23 no.6
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• pp.620-625
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• 2000

The mechanisms of liver injury from cold storage and reperfusion are not completely under-stood. The aim of the present study was to investigate whether the inactivation of Kupffer cells (KCs) by gadolinium chloride ($GdCl_3$) modulates ischemia-reperfusion injury in the rat liver. Hepatic function was assessed using an isolated perfused rat liver model. In livers subjected to cold storage at $4^{\circ}C$ in University of Wisconsin solution for 24 hrs and to 20 min rewarm-ing ischemia, oxygen uptake was markedly decreased, Kupffer cell phagocytosis was stimulated, releases of purine nucleoside phosphorylase and lactate dehydrogenase were increased as compared with control livers. Pretreatment of rats with $GdCl_3$) , a selective KC toxicant, suppressed kupffer cell activity, and reduced the grade of hepatic injury induced by ischemia-reperfusion. While the initial mixed function oxidation of 7-ethoxycoumarin was not different from that found in the control livers, the subsequent conjugation of its meta-bolite to sulfate and glucuronide esters was suppressed by ischemia-reperfusion, CdCl$_3$restored sulfation and glucuronidation capacities to the level of the control liver. Our findings suggest that Kupffer cells could play an important role in cold/warm ischemia-reperfusion hepatic injury.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.289-298
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• 1996

Eight kinds of poly(oxyethylene, oxyisopropylene) dodecyl ethers were synthesized by adding ethylene oxide and isopropylene oxide with each 5 and 10 moles alternatively on dodecanol. The addition of EO and PO for eight kinds of sodium poly(oxyethylene, oxyisopropylene) dodecyl ether sulfates was identified with HPLC, $^1H$ NMR, hydroxy value, and IR spectrum. In order to verify the sulfation the number of EO and PO molecules was obtained by spectra and Epton method. The yields of products sulfated by chlorosulfonic acid were 90~96%.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.365-370
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• 2005

The objective of this study is to develop the sorbent of oyster shell, which can remove gaseous acid pollutants emitted from the incinerator and power plants. The physicochemical properties of prepared absorbents have been measured using ICP and BET Also, this study is to investigate the Hydration/calcination reaction in the fixed bed reactor. Thus, the results could be summarized as follows. Oyster shell can be used in powder type without former processing. It should be also noted that sulfation reactivity of oyster sample increases to about 5 times by calcination/hydration reaction due to the increase of specific surface area and pore volume. From these experiments, we have found that both $SO_2$ and $NO_x$ in simulated flue gas can be effectively removed by use of oyster absorbent.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.4
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• pp.288-294
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• 1993

Flue gas control systems for small-scale combustors must be designed to provide highly effective removal of three criteria pollutants (S $O_{2}$, N $O_{x}$ and particulate matter), and must be safe, reliable and small. These requirements make dry, regenerative clean-up process particularly attractive and this paper describes a new concept for integrated pollutant control : a filter comprised of layered, gas permeable membranes that act as an S $O_{2}$ sorbant, a N $O_{x}$ reduction catalyst and a particulate filter. A mixed metal oxide sorbent, Cu-Ce was used as a sorbent/catalyst and the activity was compared with Cu-7Al. The S $O_{2}$ removal eficiency of Cu-Ce was increased with temperature increase up to 500$^{\circ}$C and the catalytic activity for NO was higher than that of Cu-7Al. By the sulfation of Cu-Ce, the reduction activity was increased at the temperature higher than 350$^{\circ}$C. The regeneration of Cu-Ce was very fast and some amount of elemental sulfar was found.

• YAKHAK HOEJI
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• v.44 no.3
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• pp.237-244
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• 2000

Liver isolated from 18 hours fasted rats was subjected to $N_2$hypoxia (for 45 min) followed by reoxygenation (for 30 min). The perfusion medium used was Krebs-Henseleit bicarbonate buffer (pH 7.4, $37^{\circ}C$). Vitamin C (0.5 mM) and trolox C (0.5 mM), soluble vitamin E analog, were added to perfusate. Lactate dehydrogenase (LDH), total glutathione, oxidized glutathione, lipid peroxide and drug-metabolizing enzymes were measured. After hypoxia LDH significantly increased but this increase was attenuated by vitamin C and combination of vitamin C and E. Total glutathione and oxidized glutathione in perfusate markedly increased during hypoxia and this increase was inhibited by vitamins C, E and its combination. Similarly; oxidized glutathione and lipid peroxide in liver tissue increased after hypoxia and reoxygenation and this increase was inhibited by vitamin I and combination of vitamin C and E. Hepatic drug metabolizing function (phase I, II) were suppressed during hypoxia but improved during reoxygenation. While vitamins C and E only increased glucuronidation, the combination of vitamin C and E increased the oxidation, glucuronidation and sulfation. Our findings suggest that vitamins C and E synergistically ameliorates hepatocellular damage as indicated by abnormalities in drug metabolizing function during hypoxia/reoxygenation and that this protection is in major part, caused by decreased oxidative stress.

• Fisheries and Aquatic Sciences
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• v.22 no.11
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• pp.24.1-24.7
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• 2019

Sporophylls from sea mustard, Undaria pinnatifida, which are by-products in seaweed production industries, were taken from Hansan Island, Tongyeong, and Gijang, Busan, and investigated for their fucoidan content and corresponding antioxidant activities. The extracted fucoidan yield from sporophylls of sea mustard samples from Tongyeong (TF) and Gijang (GF) were 12.1% and 13.6%, respectively. The antioxidant activities assessment of TF and GF extracts showed relative significant difference between samples, suggesting effect of location on bioactivities of fucoidan samples. GF was 50-68% more effective than TF against DPPH and superoxide radicals samples which may be attributed to the difference in their degree of sulfation and monosaccharide composition. Meanwhile, TF exhibited greater scavenging activity against hydroxyl radicals compared to GF which could be due to protein impurities.

• YAKHAK HOEJI
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• v.36 no.4
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• pp.350-356
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• 1992

Anticoagulant activities were tested for the fifteen kinds of medicinal plants by measuring activated partial thromboplastin time (aPTT). Of them five kinds or species (Artemisia princeps, Sanguisorba officinalis, Artemisia apiacea, Eclipa alba, Schizonepeta tenuifolia) were selected and fractionated for the preparation of acidic polysaccharides. They were extracted with water by refluxing and the extracts were precipitated with ethanol. The precipitates were separated based on charge using a DEAE-Sephadex. The low salt and high salt fractions were sulfated with anhydrous pyridine and chlorosulfonic acid complex. In vitro anticoagulant activities of sulfated polysaccharides were tested by measuring aPTT, prothrombin time (PT), and factor Xa clotting time using normal human plasma. No relationship was found between the amount of uronic acids and anticoagulant activities, but the sulfated ones show the increase of activities. In vivo anticoagulant properties of the sulfated polysaccharide from Artemisia apiacea were also tested by the intraveneous administration of three different doses (3,5 and 10 mg/kg) to rats. APTT and PT were increased significantly and the action of factor Xa and thrombin mediated through antithrombin III were inhibited slightly.

• Journal of The Korean Society of Integrative Medicine
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• v.6 no.4
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• pp.183-189
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• 2018

Purpose : As age increases, a low-level systemic inflammatory state develops and the levels of anti-aging hormones decrease. The vagus nerve activates parasympathetic nerves and promotes sulfation and secretion of neurotransmitter in the brain. Therefore, the purpose of this study was to investigate the effects of electrical vagus nerve stimulation on systemic inflammation (CRP) and anti-aging hormone (DHEA-S) levels in elder people. Methods : A total of 30 healthy elder people participated in this study, randomly divided into two groups of 15 subjects. Electrical vagus nerve stimulation was applied to the experimental group for 4 weeks. CRP and DHEA-S levels were compared with those of the control group. Results : The CRP level was significantly lower in the experimental group than in the control group. In the experimental group, there was a significant decrease in CRP before and after the intervention. However, the DHEA-S level was not significantly different between groups. Conclusion : Electrical vagus nerve stimulation may alleviate the low-level systemic inflammatory state found in elderly people. These results suggest that it may have the effect of reducing the degenerative inflammatory diseases of the elderly and delaying aging.