• Textile Coloration and Finishing
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• v.2 no.1
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• pp.31-36
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• 1990

The electrically conducting cellulose acetate/polypyrrole composite films were synthesized by exposing cellulose acetate film containing oxidizing agent to pyrrole vapour and the formation of polypyrrole is confirmed by IR and electron microscopic studies. The morphologies of polypyrrole in the composites are different depending on the oxidizing agent. Ferric chloride is most effective among several metallic chlorides to synthesize the composites with high electrical conductivity. The conductivity of composite films synthesized with 50 wt.% of ferric chloride reaches upto $10^{-2}S/cm$.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1466-1468
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• 2006

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.3
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• pp.292-296
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• 2024

In this study, Iron (III) oxide-hydroxide (δ-FeOOH) was successfully synthesized using hydrogen peroxide (H₂O₂) as an oxidizing agent. The synthesis of δ-FeOOH was carried out by controlling the amount of H₂O₂, and pure δ-FeOOH was successfully synthesized in ranges from 0.2 mL to 0.6 mL of H₂O₂. The size of the synthesized δ-FeOOH particles was compared by controlling the amount of oxidant H₂O₂. The average particle size of the synthesized pure δ-FeOOH particles increased from 875.1 nm to 897.2 nm as the amount of H₂O₂ was increased. The optical properties of δ-FeOOH synthesized under these specific conditions were investigated. All δ-FeOOH showed a similar trend of increasing and decreasing light absorption from 800 nm to 400 nm, although there was a slight difference in the amount of light absorption, with the largest amount of light absorption at 410 nm. The band gap energy of δ-FeOOH through the Tauc plot method was about 2.1~2.2 eV when H₂O₂ was 0.2~1.4mL. With a sufficient small particle size, simple control of that particle size, and a small band gap energy enough to absorb light in the visible spectrum, δ-FeOOH could be useful in a variety of applications, including photoelectrochemistry and battery electrodes.

• Applied Chemistry for Engineering
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• v.31 no.5
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• pp.581-584
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• 2020

The effect of a chemical pretreatment on the surface carbon was investigated using a scanning electron microscope (SEM) and electrochemical methods. Primitive carbon has a reducing power likely due to incompletely oxidized functional groups on the surface. We aim to control this reducing power by chemical treatment and apply for the spontaneous deposition of nanoparticles (NPs). Highly ordered pyrolytic graphite (HOPG) was initially treated with a reducing agent, NaBH4 or an oxidizing agent, KMnO₄, for 5 min. Subsequently, the pretreated carbon was immersed in a platinum (Pt) precursor. Unexpectedly, SEM images showed that the reducing agent increased spontaneous PtNPs deposition while the oxidizing agent decreased Pt loading more as compared to that of using bare carbon. However, the amount of Pt on the carbon obviously decreased by NaBH₄ treatment for 50 min. Secondly, spontaneous reduction on pretreated glassy carbon (GC) was investigated using the catalytic hydrogen evolution reaction (HER). GC electrode treated with NaBH4 for a short and long time showed small (onset potential: -640 mV vs. MSE) and large overpotential for the HER, respectively. Although the mechanism is unclear, the electrochemistry results correspond to the optical data. As a proof-of-concept, these results demonstrate that chemical treatments can be used to design the shapes and amounts of deposited catalytic metal on carbon by controlling the surface state.

• Journal of the Korean GEO-environmental Society
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• v.12 no.2
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• pp.15-22
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• 2011

In this study, the effect of surface coating on iron-sulfide mineral for preventing the product acid mine drainage(AMD) was progressed by oxidation process of sulfide minerals abandoned mine Area. Three abandoned mines, Yongdong coal mine, Sil Lim mine, and Il Koang mine were selected as a sulfide mineral resource due to higher contamination rate. Six coating agents, apatite, limestone, mangnite, dolomite, bentonite, and cement were used for preventing the AMD with $H_2O_2$ and NaClO as a oxidizing agent helping for oxidizing process on sulfide minerals. Experimental results showed that sulfide mineral surface was coated effectively. Cement has a higher ability of preventing AMD when the ratio of cement to mineralis 1:1 and experimental condition is maintaining 4Days.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.3
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• pp.93-102
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• 2023

This study investigated the possibility of treating heavy metal pollutants existing in the air in addition to simultaneously removing NOx and SOx by injecting oxidizing and reducing agents into a scrubber into a microbubble device to create an eco-friendly method that does not generate secondary pollutants. Lead compound (Pb) was selected as the heavy metal substance in the air to be treated with microbubbles, and the removal efficiency was confirmed. By treating microbubbles by connecting them to a scrubber, it was confirmed that not only NOx and SOx but also heavy metal substances in the air were reduced, cost was reduced, and secondary environmental pollutants were not generated. Through this study, it was possible to simultaneously remove NOx, SOx, and heavy metals at low cost by applying an eco-friendly method, rather than the existing high-cost treatment method such as SCR. If oxidizing agent, reducing agent, and microbubbles are used appropriately, economical and efficient air pollution can be achieved. Since material processing was possible, it is expected to be helpful in the technological development of environmental prevention facilities.

• Korean Journal of Exercise Nutrition
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• v.17 no.2
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• pp.43-48
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• 2013

This study aims to investigate changes in plasma lipid concentrations and appetite-regulating hormone levels after a 4% body fat reduction using a 9-week intervention involving aerobic exercise, a fat-oxidizing agent, and diet limitation. After the 9-week intervention, the aerobic exercise plus hydroxycitric acid (EX+HCA), exercise (EX), and diet limitation (DIET) groups achieved the target 4% body fat reduction from the baseline value. None of the plasma lipid indicators showed significant intergroup differences, indicating that plasma lipid levels are not influenced by body weight regulation. With regard to appetite-regulating hormones, no significant intergroup differences were observed in glucose, insulin, or glucagon-like peptide-1 levels, unlike ghrelin and leptin. Ghrelin levels in particular tended to decrease in the DIET group and increase in the HCA+EX and EX groups. Leptin levels significantly decreased in the HCA+EX and EX groups, whereas no differences were observed in the DIET group. Such results indicate that exercise alone without the administration of obesity diet supplements induces elevation in ghrelin levels and reduction in leptin levels, but that diet restriction alone does not influence changes in leptin levels. Taken together, we could not confirm any synergic effects arising from the use of a fat-oxidizing agent during an exercise program to control body weight. Furthermore, diet limitation unsupported by exercise had no effect on muscle mass reduction or appetite-regulating hormone levels; thus, it is not recommended as an effective body weight control method.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.3
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• pp.272-277
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• 2004

The primary aim of this study is to investigate new semi-abrasive free slurry including acid colloidal silica and hydrogen peroxide for copper chemical-mechanical planarization (CMP). In general, slurry for copper CMP consists of colloidal silica as an abrasive, organic acid as a complex-forming agent, hydrogen peroxide as an oxidizing agent, a film forming agent, a pH control agent and several additives. We developed new semi-abrasive free slurry (SAFS) including below 0.5％ acid colloidal silica. We evaluated additives as stabilizers for hydrogen peroxide as well as accelerators in tantalum nitride CMP process. We also estimated dispersion stability and Zeta potential of the acid colloidal silica with additives. The extent of enhancement in tantalum nitride CMP was verified through anelectrochemical test. This approach may be useful for the application of single and first step copper CMP slurry with one package system.

• Journal of the Korean Wood Science and Technology
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• v.16 no.3
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• pp.5-16
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• 1988

This experiment was executed to investigate the effect of activation of veneer surface by oxidizing agents, hydrogen peroxide and nitric acid, on bonding characteristics of Malas(Homalium foetidum Benth) plywood, in which the effects of these oxidizing agents amount, pretreatment time, and pressing time and temperatue on shear strength of the plywood were examined and discussed. In this research the activation of veneer surface by oxidants was effective in raising shear strength but the difference in shear strength was not observed between hydrogen peroxide and nitric acid treatment. Hydrogen peroxide treatment, however, seemed to be more profitable to industrial application because of its lower concentration and easier handling than nitric acid. The bonding method by lignin-phenol adhesive through surface activation revealed inferior shear strength to phenol- and urea-formaldehyde adhesive but superior water resistance to urea-formaldehyde adhesive and this bonding method, in addition, have the advantage of lower cost compared with phenol-formaldehyde adhesive, Therefore, this bonding method by lignin-phenol adhesive through surface activation seemed to economical in manufacturing of water-resistant wood panel materials in future.

• Resources Recycling
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• v.24 no.4
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• pp.32-37
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• 2015

Cobalt is abundant only in some countries including Democratic Republic of the Congo. It would be necessary to secure overseas Co ores and Co extraction technology. Two kinds of matte varying the sulfur content were manufactured by smelting reduction of Co concentrate containing ~8 wt% Co, ~19 wt% Cu, and ~3 wt% Fe. The amount of Co, Cu and Fe was concentrated to 19~21 wt%, 39~41 wt%, and 7~9 wt% respectively in the resulting matte. High-pressure leaching of matte was performed in an autoclave with considering the effect of oxidizing agent, $H_2SO_4$ concentration as a lixiviant, and the amount of sulfur added to the matte. An oxidizing agent (oxygen) is necessary to improve Co leaching efficiency enabling usage of a dilute $H_2SO_4$ leaching agent. An increase in $H_2SO_4$ concentration prevents selective leaching of Co, and the sulfur content in matte has a minor influence on the Co leaching efficiency.