• Korean journal of food and cookery science
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• v.8 no.2
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• pp.95-105
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• 1992

This study was carried on the Seasoning Oil production by Autoclaving Method in order to research a developed method. The Raw, Extract states of seasoning vegetables-Garlic, Onion and Ginger were added 40, 60% (w/w) of total amounts to corn salad oil. All samples treated with various conditions were determined physicochemical characteristics by Acid value, Peroxide value, Iodine value, Refractive Index, and Volatile Carbonyl Compound Content during incubating $(40{\pm}2^{\circ}C)$ and heating $(185{\pm}2^{\circ}C)$. The results were obtained as follws; 1. During incubation at $40{\pm}2^{\circ}C$, the order of antioxidative effects among seasoning vegetables was Ginger>Garlic>BHA>Onion and Extract state were more effective man Raw state. also the antioxidative effects of the seasoning vegetables were increased proportionally with the concentration in the Seasoning Oils. 2. In the case of heat treatment $(185{\pm}2^{\circ}C)$, AV, POV, IV and RI of each Seasoning Oil were changed very sharply. The antioxidative effect and Carbonyl Compound Content according to heat treatment differed from the type and concentration of seasoning vegetables in oil. Ginger had the most excellent antioxidative effect among seasoning vegetables, and m any case, the adding states of seasoning vegetables into oils were more effective in Extract man Raw states. 3. According to those results, each Seasoning Oil made from Garlic, Onion, Ginger was shown to have antioxidative properties specially in Ginger-Extract-Seasoning Oil. also the Autoclaving Method was thought to be rational method in preparation of Seasoning Oil.

• Carbon letters
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• v.16 no.2
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• pp.121-126
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• 2015

Carbon fibers are prepared by stabilizing pitch fibers accompanying electron beam (E-beam) irradiation. The carbon fibers pretreated by E-beam irradiation achieve a higher stabilization index than the carbon fibers that are only heat-stabilized. In addition, the carbon fibers subjected to E-beam irradiation in the stabilization step exhibit a comparable tensile strength to that of general purpose carbon fibers. The carbon fibers pretreated with an absorbed dose of 3000 kGy have a tensile strength of 0.54 GPa for a similar fiber diameter. Elemental, Fourier-transform infrared spectroscopy, and thermogravimetric analyses indicate that E-beam irradiation is an efficient oxidation and dehydrogenation treatment for pitch fibers by showing that the intensity of the aliphatic C-H stretching and aromatic $CH_2$ bending (out-of-plane) bands significantly decrease and carbonyl and carboxylic groups form.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.234-241
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• 1995

Effect of microwave heating on the oxidative stability of the soybean oil, sesame oil, butter and margarine were investigated by mearsuring fatty acids amout and tocopherol losses. The index for chemical properteis, free fatty acid, peroxide value, anisidine value, carbonyl value, conjugated diene and triene levels were also mearsured in the oil samples for 5, 10, 15 and 20 min of heating in a microwave oven. No significant difference was observed on the fatty acids composition in the fats and oils before and after microwave heating. During microwave treatment, the oxidative degradation of the tocopherols in the samples became greater with increasing heating time. The amount of tocopherols in the soild fats, butter and margarine, dropped drastically after 5 min of heating and reduced to 95% of their original levels after 20min heating ${\gamma}$-tocopherol in butter showed the most unstable states and completely destroyed during microwave treatment for 20min. On the other hand, 80% of tocopherols in the liquid oils were still remained after 5min of heating except $\delta$-tocopherol in sesame oil.

• Polymer(Korea)
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• v.26 no.4
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• pp.452-461
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• 2002

In this study, the effect of various concentrations of antioxidants on thermo-oxidative degradation of polyamide 6 was investigated. Unstabilized and stabilized polyamides 6 were subjected to long-term oven aging in ambient atmosphere at 70~$160^{\circ}C$. All of specimens were discolored within 100 hr at temperature range of 70~$160^{\circ}C$. Optimum antioxidant concentration was determined from the data of mechanical properties, yellowness index and relative viscosity. The synergistic effect of each primary and secondary antioxidant concentrations was not observed. Yellowing phenomenon was explained by using NMR, IR and EA. Different carbonyl groups were detected by $^{13}C$/NMR. During thermooxidative degradation, oxygen consumptions were determined by EA. The lifetime after long-term aging was predicted using Arrhenius equation.

• Preventive Nutrition and Food Science
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• v.3 no.1
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• pp.27-35
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• 1998

Starch-polyethylene films containing high molecular weight(NW) oxidized-polyethylene and prooxidant were prepared , and thermal -and bio-degradability of the films were determined. Increased levels of starch resulted in a corresponding reduction in mechanical strength of the films. However, the addition of high MW oxidized-polyethylene did not significantly reduce the percent elongation of the films. Thefilms containing high MW oxidized-polyethylene andproosicant were degreaded faster than those containing no aadditive during the heat treatment. The films lost their measureable mechanical properties when their weight-average MW(Mw) fell below 50,000. Biodegradability of the films was determined by a pure culture assay with either Streptomyces badius 252.S. setonii 75Vi2 or S. viridosporous T7A, and by an extracellulr enzyme assay using S. setonii 75vi2. The results from pure culture assay indicated that biomass accumulation on the film surface inhibited chemical and biological degradation of the films. The extracellular enzyme assay demonstrated decrease of percent elongation and increase of carbonyl index of the films. Therefore, extracellular enzyme assay could be used as a good method to evaluate biodegradability of the films.

• Macromolecular Research
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• v.17 no.8
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• pp.603-608
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• 2009

Novel ultra-high molecular weight polyethylene (UHMWPE)/zirconia composites were previously prepared by the in situ polymerization of ethylene using a Ti-based Ziegler-Natta catalyst supported on to the surface of zirconia, as a bearing material for artificial joints. Tribological tests revealed that a uniform dispersion of zirconia in UHMWPE markedly increased the wear resistance. The effects of zirconia content on the oxidation behavior of the ${\gamma}$-ray-treated UHMWPE/zirconia composite surfaces were examined. The oxidation index that estimates the oxidation degree as the content of total carbonyl compounds was monitored using Fourier transform infrared spectroscopy-attenuated total reflectance. The changes in the surface composition due to the oxidation were confirmed by electron spectroscopy for chemical analysis. The extent of oxidation decreased with increasing zirconia content, which was attributed to the increased crystallinity as well as the decreased polymer portion of the UHMWPE/zirconia composites.

• Polymer(Korea)
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• v.38 no.1
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• pp.49-53
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• 2014

A novel monomeric UV-absorber was prepared by the reaction of 2,4-dihydroxybenzophenone with N-4-chlorocarbonylphenylmaleimide in the presence of triethylamine. This reactive maleimide was grafted onto polypropylene (PP) by the thermal melt-processing in a mini-max-moulder. IR spectroscopic method was used for the quantitative determination of the extent of grafting of monomeric maleimide. To find the optimal reaction conditions, the dependence of reaction temperature and time and the concentration of monomeric UV-absorber was investigated on the grafting yields. The photooxidative effect of the grafted PP was evaluated in the weatherometer comparing to the PP mixed with UV-absorbers using the carbonyl index of IR spectrum. The grafted PP showed an excellent anti-photooxidative effect.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.1
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• pp.110-124
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• 2007

In this study, the control efficiency of odorous compounds was measured from diverse control process units of 14 individual companies located within the Ban-Wall industrial complex of Ansan city, Korea (January to July 2005), To quantify the control efficiency levels of major odorous compounds, we collected odor samples from both the front and rear side of 17 control process units ($N=17{\times}2=34$). If the control efficiency is compared for each of 32 compounds between different process units, wet scrubber (WS) was found to be the most effective unit in terms of the sum of pollutants showing the positive control signals. Although the WS system shows generally a good control pattern for VOC, it is not the case for most index odorous pollutants; only 3 out of 12 index compounds were found to show positive control efficiencies. The results of the study also indicated that the control efficiency differ greatly between different industrial sectors and/or control process types. In the case of leather industry, carbonyl compounds were found to exhibit the highest control efficiency with its values varying from 19 to 90%. On the other hand, in the case of metal production sector, VOC recorded the maximum control efficiency with values varying from 18 to 79%. According to this study, most air pollution control facilities operated in most companies show fairly poor control efficiencies for most malodor compounds. Hence, to obtain best control efficiency of odorous pollutant emission, acquisition of better information on source characteristics and establishment of effective control technologies are highly demanding.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.198-204
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• 1979

In order to obtain the basic data for processing adaptability of hazelnut, physico-chemical properties and heat stability of hazelnut oil were invest igated, and the results obtained are summarized as follows. 1. Hazelnut showed highly nutrient value as the content of oil and protein were 59.6% and 17.35, respectively. 2. In physicochemical properties of hazelnut oil, refractive index was 1.469, specific gravity 0.912, saponification value 167.3 and iodine value 63.43, therefore, it was found to be non-drying oil. 3. In composition of fatty acids in hazelnut oil, oleic acid was contained much in comparisoon with other fatty acids, and which was similar to olive oil. 4. 18 kinds of amino acids were existence in protein of hazelnut cake and among these the content of glutamic acid was the highest. 5. The peroxide value were the highest in the heat ing at $150^{\circ}C$ for 30 hours and at $180^{\circ}C$ for 10 hours, and then decreased as the heating time were longer. The carbonyl value was increased as heating time passed. 6. Acid value of hazelnut oil in the heating at $150^{\circ}C$ for 30 hours and at $180^{\circ}C$ for 10 hours were similar to each other.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.1
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• pp.54-63
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• 2010

Recently, as the function of largest supplier of biomass for "low carbon green growth", the necessity for systematic management of afforestation areas is emphasizing. The forestation of seedling, besides the afforestation cost itself, is required some additional follow-up management costs, like mowing and fertilizing of forestation area, and removal of bindweed. The mulching mat for afforestation seedlings is available for rooting of little seedlings as well as initial forestation expenses. Mulching technique is also used to control soil temperature and moisture by covering the surface of ground. In this study, the paper based-mulching film coated with biodegradable polymer and functional additive was specially produced using laboratory bar coater, and analyzed for its degradable behavior. Coating colors were prepared by dissolving PE (polyester) 80 % and PLA(polylactic acid) 20 % in chloroform and finally applied to handsheet prepared by preceding study conditions. Base paper and polymer-coated paper were artificially aged by 2 kinds of degradation methods, which are soil degradation by microorganism and light degradation by 257 nm UV wavelengths. Strength property, oxidation index and morphological property were evaluated by reduction rates of tensile strength, FTIR spectra ratio of carboxyl and carbonyl group and SEM micrograph. As these results, polymer coated-paper was superior to base paper in degradation behaviors, having results with lower reduction rate of strength properties.