• 한국수소및신에너지학회논문집
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• 제2권1호
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• pp.47-56
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• 1990

Pure titanium rods were oxidized by anodic oxidation, furnace oxidation and flame oxidation and used as a electrode in the photodecomposition of water. The maximum photoelectrochemical conversion efficiency(${\eta}$) was found for flame oxidized electrode ($1200^{\circ}C$ for 2 min in air), 0.8 %. Anodically oxidized electrodes have minimum photoelectrochemical conversion efficiencies, 0.3 %. Furnace oxidized electrode ($800^{\circ}C$ for 10min in air) has 0.5% phtoelectrochemical efficiency and shows a band-gap energy of about 2.9eV. The efficiency shows a parallelism with the presence of the metallic interstitial compound $TiO_{O+X}$(X < 0.33) at the metal-semiconductor interface, the thickness of the sub oxide layer and that of the external rutile scale.

• 펄프종이기술
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• 제35권1호
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• pp.19-26
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• 2003

In recent years, numerous studies have been carried out to find out the possible substitution of PE-coated paperboards used in packaging of watery or oily foods. Accordingly, this study was carried out to obtain the basic data for producing higher functional coating agents for pulp mold by evaluating various kinds of mixed coating agents. At that time, two kinds of synthetic coating agents(AKD, PYA) and three kinds of natural coating agent(CMC, corn starch, oxidized starch) were used for making the mixed coating agents respectively. Physical properties of coated paperboards were tested. Conclusions obtained from this study were as follows. Based on concentrations, the proper mixture ratios were 10:90(AKD:CMC), 10:90(AKD:corn starch), 10:90(AKD:oxidized starch), 40:60(PVA:CMC), 20:80(PVA:corn starch) and 20:80(PYA:oxidized starch). The mixed coating agent of PYA:corn starch(20:80) was the most efficient coating agent. Consequently, water and oil resistance were improved even with much addition of natural coating agents. We consider that they can be suitable for the packaging used in the storage of higher moisture vegetables and other food, and also can be suitable for oily fried food.

• Asian-Australasian Journal of Animal Sciences
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• 제20권10호
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• pp.1600-1605
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• 2007

This study was undertaken to investigate the effects of oxidative stress on growth performance, nutrient digestibilities and activities of antioxidant enzymes of weanling pigs. In the experiment, 24 male $Landrance{\times}Yorkshire $weanling pigs were allotted to three groups of 8 animals each. Pigs were fed individually. According to a single factorial arrangement, pigs received diets with 5% of either fresh (group 1 and group 3) or oxidized fish oil (peroxide value was 786.50 meq $O_2/kg$ before inclusion in the diet, group 2). At the beginning of the experiment, pigs in group 3 received an intraperitoneal injection of diquat at 12 mg/kg of body weight. The trial lasted for 26 d. A metabolism test was carried out during the last 4 days of the second week. The results showed that feeding diets containing oxidized fish oil or injection with diquat depressed the growth performance and nutrient digestibilities of weanling pigs, decreased activities of antioxidant enzymes and increased concentration of malondialdehyde in plasma and liver. Intraperitoneal injection of diquat would induce more serious oxidative stress than oral intake of oxidized fish oil in the diet. In conclusion, administration of oxidized fish oil or diquat could induce oxidative stress in weanling pigs, and oxidative stress could depress growth performance and impact anti-oxidative ability of young pigs.

• 한국세라믹학회지
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• 제41권5호
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• pp.359-363
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• 2004

Photoluminescence excitation (PLE) spectroscopy studies were performed for anodically etched porous Zn, which exhibited a PL in the blue/violet spectral range peaking at 420 nm (2.95 eV), and oxidzed porous Zn at 380$^{\circ}C$ for 10 min and 12 h. A broad absorption band was observed at 4.07 eV (305 nm), 3.49 (355 nm) for anodically etched porous Zn. In contrast, both the oxidized porous Zn and sintered ZnO exhibited an almost identical one broad absorption band at 3.85 eV (322 nm), when PLE spectra were measured at 378 nm (3.28 eV). The oxidized porous Zn and sintered ZnO, which displayed both UV and green luminescence band, showed an additional absorption band at 389 nm (3.19 eV) and 467 nm (2.66 eV). In contrast, no significant absorption band was detected for a 10-min oxidized porous Zn, which only displayed one UV luminescence void of deep-level luminescence. These absorption bands determined by PLE studies enabled a clear understanding of an emission mechanism for the UV and green luminescence from ZnO.

• 약학회지
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• 제35권1호
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• pp.45-60
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• 1991

lonophores, uniquely, create specific pathways of ion permeability in model and cell membranes. Calcium-transporting ionophores of microbiological origin, such as A23187 and ionomycin, have been used as experimental tools to elucidate the physiological role of calcium as a second messenger in many cell types. These ionophores are believed to bypass the initial ligand-receptor step in the activation of cells by increasing membrane permeability to calcium. In this report, we shall discuss several naturally occurring substances that share some properties of calcium-ionophores, primarily concentrating on oxidized fatty acids. We have previously demonstrated that oxidized linoteic and arachidonic acids, obtained either by lipoxygenase catalysis or nonenzymatic processes, significantly promote calcium translocation in a two-phase partition model and modulate calcium-transporting function in the isolated sarcoplasmic reticulum vesicles obtained from mammalian hearts. We have also confirmed that calcium-ionophoric properties are due not to their general amphiphilic nature of certain lipids, but to distinct structural characteristics. Although there are some skeptical views on the occurrence of ionophores in higher organisms, increasing evidence suggests that membrane lipids or their derivatives may serve as physiological calcium-ionophores. Abnormal accumulation of lipid peroxidation products(particularly end products), however, may be associated with the general oxidative damages as seen in many pathological conditions.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 제3회 압연심포지엄 논문집 압연기술의 미래개척 (Exploitation of Future Rolling Technologies)
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• pp.412-422
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• 1999

Scale defects generated on the strip surface in a tandem finishing mill line are collected from the strip trapped among the production mills by freezing the growing scale on the strip by the melt glass coating and shutting down the line simultaneously. The samples observed of its cross sectional figure showed the process of scale defect formation where the defects are formed at the base metal surface by thicker oxidized scale during each rolling passes. The properties of the oxidized layer growth both at rolling and inter-rolling are detected down sized rolling test simulating carefully the rolling condition of the production line. The thickness of the oxidized layer at each rolling pass are simulated numerically. The critical scale thickness to avoid the defect formation is determined through the expression of mutual relation between oxidized layer thickness and the lanks of the strip called quality for the scale defects. The scale growth of scale less than the critical thickness and also to keep the bulk temperature tuning the water flow rate and cooling time appropriately. Two units of Inerstand Cooler are designed and settled among the first three stands in the production line. Two units of scale defect is counted from the recoiled strip and the results showed distinct decrease of the defects comparing to the conventionaly rolled products.

• Journal of the Korean Wood Science and Technology
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• 제43권6호
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• pp.740-745
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• 2015

본 연구에서는 HPC (hydroxypropyl cellulose)와 TEMPO 산화된 셀룰로오스 나노섬유(Tempo-oxidized cellulose nanofibrils, TOCN)가 보강된 복합필름을 제조하였다. 복합필름의 기계적, 열적 특성을 관찰하기 위해 인장강도 및 열중량 분석기(TGA)를 측정하였다. HPC/TOCN 복합필름에서 TOCN의 함량이 1 wt%에서 5 wt%까지 증가할수록 인장강도와 인장탄성계수는 직선적으로 증가하는 경향을 보였다. 그러나 TGA 분석 결과, TOCN의 함량에 관계없이 HPC/TOCN 복합필름의 열 안정성은 거의 차이가 없었다.

• 한국식품영양과학회지
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• 제32권7호
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• pp.1046-1052
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• 2003

Viscoelastic behavior of oxidized starch gel, modified with sodium hypochlorite (NaOCl) and the adding effects of protein in oxidized starch gel was studied by dynamic viscoelastic measurement. The storage modulus(G′) of starch gel increased with the increase of starch concentration. They showed higher value when starch suspension was treated to 95$^{\circ}C$ rather than 85$^{\circ}C$. Consistency of starch gel was decreased over 1.0% active Cl/g starch when heated to 95$^{\circ}C$, which means that the swelling of starch granules increased with concentration of NaOCl and showed more sensitive against shear. As the extent of oxidation increased, starch granules were easily destroyed. Therefore, it is hard to separate between compartment of leached-out amylose and that of amylopectin, which means that the ability of gel formation was reduced. When oxidized starches were gelatinized in presence of soy protein and sodium caseinate, it was found that G′ decreased, and frequency dependence of G′ and G" increased with the increased degree of oxidation in starch. The reduce of starch-protein interaction was thought to be through the dissociation of the branched amylopectin, which playa leading role in protein interaction, with the oxidation of starch.

• 한국염색가공학회지
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• 제9권4호
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• pp.47-53
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• 1997

To improve the interfacial bonding of carbon fiber-nylon 6 composite, carbon fiber(CF) were oxidized by nitric acid treatment, and two types of graft polymer(GP) of nylon 6-g-polyacrylamide (PAAm) -water dispersable GP(WDGP) and m-cresol solu ble GP(CSGP) were treated as coupling agents. Introduction of polar groups such as -COOH, -OH, etc, on the surface of the oxidized CF was confirmed by IR spectra. The stem polymer of nylon 6 in the coupling agent (GP) could be compatible with'matrix nylon 5, and the grafted branch of PAAm on GP could react to the polar groups on the oxidized CF in composite. The interfacial strength was measured by the transverse tensile test to the fiber direction for single CF embedded nylon 6 film especially prepared and by the pull-out test method. The interfacial strength of the composite reinforced with oxidized CF is greater than that reinforced with unoxidized CF. The interfacial strength of the composite was increased by treatment of coupling agents(GPs) considerably, and the increasing tendency by the WDGP is greater than that by the CSGP. The optimum conditions of coupling agent treatment are as follows: the concentration, adsorption tlme of GP, and curing temperature are 2%, 20 minutes, and $170^{\circ}$, respectively.

• 펄프종이기술
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• 제45권4호
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• pp.21-26
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• 2013

The effect of esterified starch as surface sizing agent for inkjet printing paper has been evaluated and compared with oxidized starch. Also the influence of various additives including cationic poly-DADMAC, stearic acrylic copolymer, calcium chloride, and GCC was examined. Results showed that starch ester gave higher ink density than oxidized starch. Addition of poly-DADMAC improved water fastness. In general, low molecular weight poly-DADMAC performed better than high molecular weight one, and it was attributed to the fact that it gave more uniform film forming characteristics in surface sizing. Use of styrene acrylic acid copolymer increased hydrophobicity of the paper surface, but it did not increase the ink density. Use of GCC and calcium chloride had only marginal effect on printing quality.