• Preventive Nutrition and Food Science
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• v.6 no.4
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• pp.211-215
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• 2001

The packaging effect on physicochemical changes in irradiated sausage stored at -2$0^{\circ}C$ was studied. Emulsion-type cooked pork sausage was made with (156 ppm) or without NaNO$_2$ (0 ppm), and packaged in three different conditions such as aerobic, vacuum and $CO_2$ (100%). The samples irradiated at 0, 5 and 10 kGy absorbed dose, and the total number of microorganisms, lipid oxidation, color and texture were analyzed during frozen storage at-2$0^{\circ}C$. Irradiation of the sausage at 10 kGy completely controlled microbial growth during storage. An NaNO$_2$ addition to the sausage significantly reduced lipid oxidation, and the TBARS value of the sausage with aerobic packaging was higher than that with the vacuum and $CO_2$ packaging. The NaNO$_2$ addition increased Hunter color a-value dramatically, but no packaging effect was found (p > 0.05). Irradiation influenced shear values resulting in lower shear values in 10 kGy-irradiated sausages with aerobic packaging, and $CO_2$ packaged sausage showed comparatively lower shear value than other packaging methods. From the results, vacuum or $CO_2$ (100%) packaging were better than aerobic packaging for frozen stored pork sausage, especially far microbial quality and lipid oxidation.

• Applied Chemistry for Engineering
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• v.21 no.2
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• pp.178-182
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• 2010

Simultaneous removal reaction for NOx, soot over Pt catalysts using various $TiO_2$ as support was studied. The catalytic tests ware carried out injectin NO, soot, NO and soot simultaneously on each catalysts. As results, it showed different NOx removal efficiency and soot oxidation rate according to various kinds of $TiO_2$. Onset temperature of soot oxidation has a correlation to $NO_2$ generated for the independently performed NOx. It was investigated that NO to $NO_2$ oxidation was intimately related to crystallite size and surface area, and it has a tremendous impact on Pt aggregation on the catalyst surface and catalyst' reducibility. Therefore, we concluded that major index of the reaction was physico-chemical properties of catalyst' supports.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.2
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• pp.282-286
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• 2013

Many manufacturing processes damage the structure of meat products and this often contributes to lipid oxidation which could influence warmed-over flavor (WOF) in precooked beef that is reheated beef. Electrical stimulation causes contraction of muscles and improves tissue tenderization. The purpose of this study was to evaluate the rate of lipid oxidation or warmed-over flavor that could be affected by electrical stimulation of precooked roast beef after refrigerated storage and reheating. The results show that there was no significant difference between chemical compositions and cooking yields when comparing non-electrically stimulated and electrically stimulated roast beef. Moreover, electrical stimulation had no significant effect on oxidative stability and off-flavor problems of precooked roast beef as evaluated by thiobarbituric acid reactive substances (TBARS) and sensory test (warmed-over aroma and warmed-over flavor). However, there was an increased undesirable WOF and a decrease in tenderness for both ES and Non-ES treatments over refrigerated storage time. Electrical stimulation did cause reactions of amino acids or other compounds to decrease the desirable beef flavor in re-cooked meat.

• Journal of Acupuncture Research
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• v.24 no.3
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• pp.99-109
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• 2007

Objectives : The purpose of this study is to observe the anti-oxidative effects of electroacupuncture at Taegye($KI_3$) in rats. Methods : The methods are measures of experimental items including change of body weight, relative liver weight, level of alblumin, total bilirubin, LDL-cholesterol, LDH, GOT and GPT in blood serum, level of SOD, GSH, catalase, NO and MDA concentration in liver, histological change of liver. Results: 1. The $KI_3$-EA group lost weight in the beginning, and gained it gradually. 2. The liver ratio of the $KI_3$-EA group increased compared to the holder group, without any statistical significance. 3. The SOD activity, Glutathione concentration, and Catalase concentration increased, and the NO concentration and MDA concentration decreased in the $KI_3$-EA group significantly, compared to the holder group. 4. $KI_3$-EA group had more similar density to the normal group, than the holder group. Conclusion : The electroacupuncture application on Kb has anti-oxidation effect, by improving the body defence against the oxidation stress- induced cytotoxicity, and by supressing the oxidative liver damage.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.209-209
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• 2002

Mycobacterium sp. strain JCl DSM 3803 grown in methanol showed no methanol dehydrogenase or oxidase activities found in mast methylotrophic bacteria and yeasts, respectively. Even though the methanol-grown cells exhibited a little methanol-dependent oxidation by cytochrome c-dependent methanol dehydrogenase and alcohol dehydrogenase, they were not the key enzymes responsible for the methanol oxidation of the cells, in that the cells contained no c-type cytochrome and the methanol oxidizing activity from the partially purified alcohol dehydrogenase was too low, respectively. In substrate switching experiments, we found that only a catalase-peroxidase among the three types of catalase found in glucose-grown cells was highly expressed, in the methanol-grown cells and that its activity was relatively high during the exponential growth phase in Mycobacterium sp. JCl. Therefore, we propose that catalase-peroxidase is an essential enzyme responsible for the methanol metabolism directly Of indirectly in Mycobacterium sp. JCl.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.959-964
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• 2008

The principal objective of this study was to assess the effects of the addition of natural plant materials on the color and lipid oxidation of ground pork. Ground pork was blended with 0.3% (w/w) of cactus, fennel seed, orange peel, and rosemary, respectively, and stored for 8 days at $2^{\circ}C$. The pH, meat color, thiobarbituric acid reactive substances (TBARS) values, and metmyoglobin (MetMb) contents were measured. A gradual increase in pH was noted with increases in the storage time. The Hunter a (redness) value decreased until 6 days of storage, and evidenced no noticeable changes there after, and the cactus evidenced significantly higher a values than other groups over time (p<0.05). The TBARS formation was effectively inhibited by the addition of rosemary for 6 days of storage, reflective of strong antioxidative activity (p<0.05). The antioxidative activity on the lipid oxidation of cooked pork patties was noted in the following order: rosemary, fennel seed, cactus, and orange peel. The MetMb contents increased according to storage period, and no significant differences were noted among the meat patties.

• The Korea Journal of Herbology
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• v.20 no.4
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• pp.103-112
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• 2005

Objectives : In order to develop effective and safe anti-oxidation, the effects of Menthae Herba (M. spicata L. and M piperita L.) were examined. Methods : M. spicata L. and M. piperita L. of Menthae Herba were used to make water extracts and methanol extracts, and then its anti-oxidative effects were compared in vitro. Results : 1. M. spicata L. was stronger than M. piperita L. in anti-oxidative effects of methanol extracts, and water extracts showed similar anti-oxidation effects. 2. Water extracts of M. spicata L. was stronger than M. piperita L. showed a stronger superoxide anit-oxidation than the same-density ascorbic acid, so that water extracts were proved to be stronger than methanol extracts. 3. Methanol extracts' DPPH anti-oxidation was similar in M. spicata L. and M piperita L.. As for water extracts, M. spicata L. showed higher anti-oxidation and M. piperita L. had no anti-oxidation. 4. As for anti-oxidation of LDL and linoleic acid of methanol extracts, both M. spicata L. and M. piperita L. were stronger than a-tocopherol. As for the water extracts, these two showed similar level of anti-oxidative effect on linoleic acid, which is weaker that mehtanol extracts. 5. M. spicata L. includes more phenol than M. piperita L. Conclusions : Menthae Herba (M. piperita L. M. spicata L.) had anti-oxidation effect, so that it can be medically developed for anti-oxidation.

• Corrosion Science and Technology
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• v.19 no.1
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• pp.43-50
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• 2020

In this study, the effects of KCl(s) and K₂SO₄(s) on the oxidation characteristics of 2.25Cr-1Mo steel were investigated for 500 h in 10O₂ + 10CO₂ (vol%) gas environmen at 650 ℃. Oxidation kinetics were characterized by weight gain, oxide layer thickness, and fitted models for the experiment data were proposed. The fitted models presented considerable agreement with the experimental data. The oxide layer was analyzed using the scanning electron microscope, optical microscope, and energy dispersive X-ray spectroscopy. The oxidation kinetics of 2.25Cr-1Mo steel with KCl and K₂SO₄ coatings showed significantly different oxidation kinetics. KCl accelerated the oxidation rate very much and had linear oxidation behavior. In contrast, K₂SO₄ had no significant effect, which had parabolic kinetics. The oxide layer was commonly composed of Fe₂O₃, Fe₃O₄, and FeCr₂O₄ spinel. KCl strongly accelerated the oxidation rates of 2.25Cr-1Mo steel in the high-temperature oxidation environment. Conversely, K₂SO₄ had little effect on the oxidation rates.

• Journal of Powder Materials
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• v.28 no.2
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• pp.110-119
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• 2021

In this study, the high-temperature oxidation properties of austenitic 316L stainless steel manufactured by laser powder bed fusion (LPBF) is investigated and compared with conventional 316L manufactured by hot rolling (HR). The initial microstructure of LPBF-SS316L exhibits a molten pool ~100 ㎛ in size and grains grown along the building direction. Isotropic grains (~35 ㎛) are detected in the HR-SS316L. In high-temperature oxidation tests performed at 700℃ and 900℃, LPBF-SS316L demonstrates slightly superior high-temperature oxidation resistance compared to HR-SS316L. After the initial oxidation at 700℃, shown as an increase in weight, almost no further oxidation is observed for both materials. At 900℃, the oxidation weight displays a parabolic trend and both materials exhibit similar behavior. However, at 1100℃, LPBF-SS316L oxidizes in a parabolic manner, but HR-SS316L shows a breakaway oxidation behavior. The oxide layers of LPBF-SS316L and HR-SS316L are mainly composed of Cr₂O₃, Fe-based oxides, and spinel phases. In LPBF-SS316L, a uniform Cr depletion region is observed, whereas a Cr depletion region appears at the grain boundary in HR-SS316L. It is evident from the results that the microstructure and the high-temperature oxidation characteristics and behavior are related.

• Progress in Superconductivity and Cryogenics
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• v.24 no.4
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• pp.40-45
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• 2022

The electrical/thermal stabilities and magnetic field controllability of a no-insulation (NI) high-temperature superconducting magnet are characterized by contact resistance between turn-to-turn layers, and the contact resistance characteristics are determined by properties of conductor surface and winding tension. In order to accurately predict the electromagnetic characteristics of the NI coil in a design stage, it is necessary to control the contact resistance characteristics within the design target parameters. In this paper, the contact resistance and critical current characteristics of a rare-earth barium copper oxide (REBCO) conductor were measured to analyze the effects of surface treatment conditions (roughness and oxidation level) of the copper stabilizer layer in REBCO conductor. The test samples with different surface roughness and oxidation levels were fabricated and conductor surface analysis was performed using scanning electron microscope, alpha step surface profiler and energy dispersive X-ray spectroscopy. Moreover, the contact resistance and critical current characteristics of the samples were measured using the four-terminal method in a liquid nitrogen impregnated cooling environment. Compared with as-received REBCO conductor sample, the contact resistance values of the REBCO conductors, which were post-treated by the scratch and oxidation of the surface of the copper stabilizer layer, tended to increase, and the critical current values were decreased under certain roughness and oxidation conditions.