• Food Science and Preservation
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• v.8 no.1
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• pp.30-36
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• 2001

Quality changes of winter Chinese cabbage with different packing and loading methods were investigated during cold storage at 0$\^{C}$. Judging from the marketability of stored Chinese cabbage, winter Chinese cabbage could be above 4 months at 0$\^{C}$ cold store. Four Chinese cabbages were packed with 0.3mm polyethylene film and then loaded vertically in plastic container. During storage at 0$\^{C}$, gas composition in the plastic bags was indicated by 8.2∼19.5% O$_2$ and 0.35∼8.58% CO$_2$, respectively. Compared to the conventional storing method, packed with polypropylene net, the fresh1ess of Chinese cabbage was prolonged nearly 10 to 20% by MAP.

• Journal of Environmental Health Sciences
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• v.7 no.2
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• pp.73-87
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• 1981

Generation of Solid Wastes grew rapidly with the increase of living standard of the people in Korea recently and their composition was more complicate. The weight of Solid wastes generated in Seoul into year of 1979 was about 420 million tons which required 1.5 million $m^2$ of burial land and daily generation for person was 1.6kg. The Composition of more than 80% ash contents was suitable for sanitary landfill but recently ash was decreasing while paper, synthetic materials, glass etc, increasing and alternative method had to be found to dispose the wastes properly. Weight and Composition of Wastes by season and living standard were surveyed for one year from June 1980 to May 1981 in Seoul. Disposal mathods by waste composition was studied. Results were summarized as follows: 1) Each component stored separately at generation point was to be collected and to be reused or disposed by public organization or private company. Some incentives have to be arranged. 2) Wastes collected from household were transfeted to about 420 temporally storing places and transported to two dumping areas by about 700, 4-8 tons trucks which droped litters on the streets. Large dumping lots should constructed along the western coasts and the wastes would be transported through big container trucks or trains to the lots. 3) Ash contents decreased to 40-70% while garbage, synthetic materials, paper increased and they are two to three times in summer of those in winter. Ash in affluent residential areas is less than 50% of whole wastes while that in poor apartment and residential areas is 60-70%. 4) Large dumping places should be constructed along the western coasts which are not far from Seoul because no suitalbe lands are available, and proper leakage protection arrangements should be made.

• Journal of the Korean Institute of Gas
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• v.15 no.1
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• pp.9-14
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• 2011

Heavy duty diesel engine has relatively small portion of whole vehicles due to long drive distance and large engine displacement, but largely influences atmosphere environment. City buses changed to CNG (Compressed Natural Gas) bus with Korea-Japan Worldcup. Heavy duty truck and intercity bus, however, were impossible to use CNG because those kinds of vehicles had long drive distance and CNG station was installed mainly at the around of the bus garage of city. Insulation container storing the natural gas as a liquid makes heavy duty truck and intercity bus possible to use the natural gas. Drive using diesel is possible where is hard to recharge the gas. With LNG (Liquefied Natural Gas), the dependence on oil is largely decreased, PM (Particulate Matter) and NOx which is chronic disadvantage of diesel is remarkably reduced and finally $CO_2$, the representative green house gas, is reduced over 10%.

• Archives of Pharmacal Research
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• v.22 no.3
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• pp.288-293
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• 1999

Postabsorptive serum iron level was determined after oral administration of the compounds to human. In serum and whole blood, $Fe^{3+}$ was measured by ion chromatography (IC) using a pyridine-2,6-dicarboxylic acid (PDCA) as an eluent. The serum sample solutions were pretreated with I N HCI and 50% TCA. The whole blood sample solutions were treated with 3 N HCI for 30 min at $125^{\circ}C$. The limit of detection (LOD) of the IC technique is $0.2 {\mu}M$ for$Fe^{2+}$and 0.1 $\mu$M for $Fe^{3+}$. The area under concentration (AUC) can be obtained by the above analytical condition. In addition, to compare the stability of $Fe^{2+}$ to that of $Fe^{3+}$ in pharamaceutical preparations, accelerated stability test was carried out. After storing the samples under $40^{\circ}C$, 75%RH in light-resistant container for various time intervals, the contents of iron of different valencies were determined separately by the IC technique and the change and/or the interchange of among those iron species in preparations was investigated. Iron raw materials are stable, but $Fe^{2+}$ in$Fe^{3+}$ source materials was slightly converted to $Fe^{3+}$ by oxidation. $Fe^{2+}$ in$Fe^{3+}$ source raw materials and $Fe^{3+}$ in $Fe^{2+}$ raw materials are determined as impurities. Therefore, IC technique is found to be an appropriate method for comparative evaluation of dissimilar bioavailability of $Fe^{2+}$ and $Fe^{3+}$, stability of $Fe^{2+}$ and $Fe^{3+}$ raw materials and preparations.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.201-206
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• 1985

This experiment was carried out to get the basic information about long term storage (Temp.: -10${\pm}$1$^{\circ}C$ and -l${\pm}$1$^{\circ}C$, RH; 30${\pm}$6) of rice germplasm by using three Japonica and one Indica x Japonica cultivars based on the storage periods (96, 86, 58 and 20 months). The germination ability, based on the storing periods, was tested under the conditions of 30-32$^{\circ}C$ and 15-17$^{\circ}C$ air temperature. The results obtained are summarized as follows: 1. There were no significant differences between the short and long term storage conditions in the percentage of germination, average germination period, germination coefficient of the four varieties tested under both 15-17$^{\circ}C$ of low and 30-32$^{\circ}C$ of optimum temperature conditions. 2. Eventhough there were no significant differences in germination depending on the storage periods under optimum temperature condition (30-32$^{\circ}C$). Longer storage duration resulted in lower germination percentage, longer average germination period and lower germination coefficient under low temperature condition (15-17$^{\circ}C$). Comparing the varieties, the germination percentage of a Indica/Japonica cultivar "Tongil" was lower than that of Japonica cultivars under the low temperature condition (15-17$^{\circ}C$). 3. The longer period of storage, the more abnormal plants had appeared. 4. The germination ability was lost earlier under the condition of high moisture content in the seed and non-ventilation container.

• Korean journal of food and cookery science
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• v.23 no.4 s.100
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• pp.452-460
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• 2007

As a preliminary study for developing cooking techniques to improve cooked rice flavor, we surveyed consumer perceptions on purchasing rice and the consumption of cooked rice. The quantity of rice purchased by consumers was in the range of $1O{\sim}20$ kg. The purchase criterion for 50% of the subjects was the taste of the cooked rice, and half of the subjects bought their rice at a supermarket. A majority (90%) of the subjects consumed the rice within 1 to 4 months, storing it raw in the package (32.4%) or in a container at room temperature. The rice was cooked for 2 to 5 persons (65%), 1 to 2 times a day (70%) with a pressure cooker (76%). The rice and water volume were measured by eye. The cooked rice was eaten immediately (41.8%) or in 1 to 2 days (48.6%) by keeping it in an electric cooker (63.6%). The subjects perceived the rice cultivar (37.9%) as the major factor for the cooked rice flavor, as well as the region of origin (21.3%), and storage period (11.9%); the cultivars of Ilmi, Ilpoom and Chuchung were preferred. In conclusion, the consumers regard rice as a principal food; however, the methods to measure rice and water are not standardized. To improve the taste of cooked rice, consumers depend on cooking equipment and the rice cultivar.

• Food Science and Preservation
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• v.19 no.1
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• pp.47-53
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• 2012

UV light irradiation is known to give beneficial effects on fresh produce preservation. A container system equipped with UV-LED was fabricated for storing cherry tomatoes under computer-controlled conditions of intermittent on-off cycles (1 hour on/1 hour off). Wavelength (365 and 405 nm) and physical location of the LED (2 and 5 cm above fruit) were studied as variables affecting the respiration, ethylene production and quality preservation of the fruits at 10 and $20^{\circ}C$. 365 nm wavelength gave much higher radiation intensity than 405 nm, and intensity on surface decreased in inverse proportion to square of distance from LED. When compared to non-irradiated control, UV-LED irradiation decreased the respiration by 5-10% at $10^{\circ}C$ while there was no obvious effect at $20^{\circ}C$. Ethylene production was reduced when the fruits were placed at 5 cm distance, while there was no significant difference from control at 2 cm location. The reduction of ethylene production at 5 cm was more pronounced at $20^{\circ}C$. UV-LED irradiation was shown to have delayed increase or lower concentration in carotenoids compared to control treatment. Any negative effect of UV-LED irradiation on ascorbic acid content and firmness was not observed.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1307-1319
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• 2018

As interests in the air pollution increases, many kinds of researches are underway on the reduction of air pollutants. The removal of nitrogen oxides from the emission gas of diesel vehicles using urea solution has shown a great effect. The quality of urea solution is strictly defined by domestic law, but the increase of impurities in urea solution reduces the effect of reducing nitrogen oxides. Therefore, in this study, the change of physical properties of urea solution was analyzed after heating the urea solution for a certain temperature and time. Also, the changes of physical properties of urea solution were analyzed according to kinds of storage container and temperature for storing the urea solution. After heating the urea solution for a certain period of time, the biuret content in urea solution increased and the content of urea decreased. As the urea content decreased, both density and refractive index decreased. In the storage stability test carried out at a constant temperature with iron and PET containers, no change in physical properties was observed.

• Journal of Nutrition and Health
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• v.44 no.1
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• pp.61-73
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• 2011

The aim of this study was to develop a reliable dietary questionnaire to assess human exposure to food-borne hazards. Eleven food-borne hazards were chosen as a priority control list through a literature review and advisory committees. The 11 food-borne hazards were phthalate, aflatoxin, bisphenol A, polycyclic aromatic hydrocarbons, dioxin, polychlorinated biphenyls, mercury, lead, cadmium, arsenic, and acrylamide. The characteristics, exposure level, and paths of these hazards were reviewed, and questionnaire items were identified to assess human exposure from the literature. A questionnaire was developed for each selected food based on its characteristics. Based on the items in the individual questionnaires, a comprehensive questionnaire, which contained demographic characteristics, job information, socioeconomic factors, health related lifestyles, and dietary behaviors, was developed. A 99-item food frequency questionnaire (FFQ) to assess food-borne hazard exposure was also developed. The FFQ included frequency of food intake during the previous year, container type for purchasing and storing food, and cooking method. The questionnaire developed in this study could be applied to assess dietary factors during an exposure assessment of food-borne hazards in a large population. A validation study for the questionnaire is needed before applying it to surveys.