• Journal of the Korean Ceramic Society
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• v.42 no.7 s.278
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• pp.475-482
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• 2005

Zn$_{l-x}$Co$_{x}$O (x = 0.05 - 0.20) films were grown on Coming 7059 glass by sol-gel process. A homogeneous and stable Zn$_{l-x}$Co$_{x}$O sol was prepared by dissolving zinc acetate dihydrate (Zn(CH$_{3}$COO)$_{2}$$\cdot$2H$_{2}$O), cobalt acetate tetrahydrate ((CH$_{3}$)$_{2}$$\cdot$CHOH) and aluminium chloride hexahydrate (AlCl$_{3}$ $\cdot$ 6H$_{2}$O) as solute in solution of isopropanol ((CH$_{3}$)$_{2}$$\cdot$CHOH) and monoethanolamine (MEA:H$_{2}$NCH$_{2}$CH$_{2}$OH). The films grown by spin coating method were postheated in air at 650°C for 1 h and annealed in the condition of vacuum (5 $\times$ 10$^{-6}$ Torr) at 300$^{\circ}C$ for 30 min and investigated the nature of c-axis preferred orientation and physical properties with different Co concentrations. Znl_xCOxO thin films with different Co concentrations were well oriented along the c-axis, but especially a highly c-axis oriented Zn$_{l-x}$Co$_{x}$O thin film was grown at 10 at$\%$ Co concentration. The transmittance spectra showed that Zn$_{l-x}$Co$_{x}$O thin films occur typical d-d transitions and sp-d exchange interaction became activated with increasing Co concentration. The electrical resistivity of the films at 10 at$\%$ Co had the lowest value due to the highest c-axis orientation. X-ray photoelectron spectroscopy and alternating gradient magnetometer analyses indicated that no Co metal cluster was formed, and the ferromagnetic properties appeared, respectively. The characteristics of the electrical resistivity and room temperature ferromagnetism of Zn$_{l-x}$Co$_{x}$O thin films suggested the possibility for the application to dilute magnetic semiconductors.

• Journal of the Korean Ceramic Society
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• v.34 no.2
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• pp.131-138
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• 1997

Silicon carbide films were chemically vapor deposited onto graphite substrates using MTS(Ch3SiCl3) as a source and Ar or H2 as a diluent gas. The experiments were performed at a fixed condition such as a de-position temperature of 130$0^{\circ}C$, a total pressure of 10 torr, and a flow rate of 100 sccm for each MTS and carrier gas. The purpose of this study is to consider the variation of the growth behavior with the addition of each diluent gas. It is shown that the deposition rate leads to maximum value at 200 sccm addition ir-respective of diluent gases and the deposition rate of Ar addition is faster than that of H2 one. It seems that these characteristics of deposition rate are due to varying interrelationship between boundary layer thick-ness and the concentration of a source with each diluent gas addition, when overall deposition rate is con-trolled by mass transport kinetics. The preferred orientation of (220) plane was maintained for the whole range of Ar addition. However, above 200 sccm addition, especially that of (111) plane was more increased in proportion to H2 addition. Surface morphologies of SiC films were the facet structures under Ar addition, but those were gradually changed from facet to smooth structures with H2 addition. Surface roughness be-came higher in Ar, but it became lower in H2 with increasing the amount of diluent gas.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.685-690
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• 2000

Caliroa carinata (Zombori) has heavily damaged the forests of Quercus mongolica in Sangju, Kyongbuk, Korea since 1996. However, information on the ecology and control of this pest was badly scarce. Thus we tried to study the ecology and chemical control of the sawfly through this study. Caliroa carinata is one generation per year. The adult sawflies emerged from June 8 to July 5 with peak at June 18. A female adult laid 11 eggs in rows on the backside of a leaf along the midribs and larger veins. Larvae have six instars, and the developmental period required to complete the larval stage was 19 days and 17 days at temperatures of $20^{\circ}C$ and $25^{\circ}C$, respectively. Each larval stage required 2-4 days to complete the development. The sawfly mostly preferred Quercus mongolica and Q. dentata, while avoiding Q. variabilis. Such insecticides as Tebufenozide, Flufenoxuron, Etofenprox, and Fenitrothion were sprayed on host plant leaves infected with test larvae in order to study the mortality. After 3 days of insecticide treatments, the mortalities were thoroughly examined. All insecticides showed higher than 95% of mortalities. Control values were also higher than 93%. The optimal season of insecticide application for pest control was estimated from late June to early July.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.246-253
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• 2012

In this study, we determined the optimum blanching conditions for pretreatment of Aster scaber prior to freezing to ensure its long, safe preservation as a fine cooking ingredient. Frozen-thawed A. scaber did not significantly differ between blanching groups, but the blanched group showed significantly higher Hunter L, a, and b values than the un-blanched group (p<0.05). Higher temperatures and longer treatment times increased softness; hardness did not significantly differ between the blanched and un-blanched groups of frozen-thawed A. scaber (p<0.05). Total bacterial counts and the presence of coliforms seemed to decline with blanching treatments, but treatment temperature and time did not influence this reduction. Over 95% of peroxidase activity was inactivated by blanching treatment but increased slightly after thawing. The sensory evaluation of the frozen-thawed A. scaber by test group showed the A. scaber blanched at $90^{\circ}C$ for 3 min to be the most highly preferred (p<0.05).

• Korean journal of applied entomology
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• v.53 no.4
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• pp.435-440
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• 2014

The number of Bemisia tabaci adults attracted to horseweed, thistle, red bean, cucumber, and tomato plants, as measured by the number stuck to yellow sticky traps, was investigated in a polyvinyl greenhouse for growing tomatoes using organic methods. The number was highest on cucumber plants in the early days of B. tabaci infestation, but was highest on horseweed overall. Of the eight species of beans tested, B. tabaci adults were most attracted to Ultari-Gangnang; however, beans were not effective trap plants for B. tabaci. Measurement of olfactory behavioral response using a four-choice olfactometer showed that B. tabaci adults preferred horseweed to cucumber, eggplant, or tomato. The developmental period of B. tabaci eggs and larvae was shorter at high temperature. At $30^{\circ}C$, the developmental period of eggs and larvae on horseweed were reduced approximately 0.5 and 1 day, respectively, compared to those on cucumber or tomato.

• Korean Journal of Food Science and Technology
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• v.49 no.3
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• pp.318-323
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• 2017

While manufacturing blended tea, the temperature for pan-firing Rhus verniciflua seed (RVS) is important. The pan-firing duration was fixed to 15 minutes according to a sensory test. We then prepared four types of blended teas with varied ratios of RVS; all the four types showed similar pH, $^{\circ}Bx$, and hunter's color values with no significant difference. According to the sensory test, A-type tea blended with RVS was the most preferred. The antioxidant activity of A-type blended tea was evaluated during storage. The changes in the total polyphenol, total flavonoid, and antioxidant activity by DPPH and ABTS assays were monitored during storage at 4, 25, and $40^{\circ}C$ for 28 days. After 28 days of storage, values for total polyphenol content, total flavonoid content, and antioxidant activity were similar to the initial values. Moreover, microbial growth was not observed during that period.

• Food Science of Animal Resources
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• v.31 no.3
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• pp.477-483
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• 2011

In this study, the most preferred trans fatty acid analysis methods, AOAC 996.06 and the Korea Food and Drug Administration official method, were reviewed and modified to apply to dairy products and dairy products imported into the Republic of Korea for evaluating trans fatty acid (TFA) content. The Rose-Gottlieb method for total fat analysis was validated with accuracy and precision parameters by analyzing infant formula standard reference material provided by the National Institute for Standards and Technology. The accuracy and precision data satisfied the CODEX guidelines. TFAs were analyzed with a resolution of 1.5 for 45 min using the modified oven temperature program. This modified method was applied to 45 dairy products from 11 countries. Average TFA contents in these imported dairy products ranged from 0.1 to 5.4 g per 100 g product. The majority of dairy products imported into the Republic of Korea were cheeses. TFA contents in the cheeses were 0.1 to 2.4 g per 100 g cheese. TFA contents in other dairy products were 1.7 to 5.4 g per 100 g product. These TFAs content variations can be explained by the trans fatty acids naturally present in ruminant milk formed by bacterial bio-hydrogenation in the rumen of cows and the different vegetable fat used as ingredients in the final products.

• Culinary science and hospitality research
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• v.19 no.2
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• pp.1-10
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• 2013

This study was conducted to investigate the quality characteristics of dumpling shells with white lotus leaf powder added to them (WLL 0%, 1%, 2%, 3%, 4%). Water binding capacity and moisture content of dumpling shells were not significantly different. Solubility in $50^{\circ}C$, $60^{\circ}C$ and $70^{\circ}C$ of dumpling dough has decreased because of the addition of WLL. Swelling power of all groups has increased because of increased amount of WLL content and temperature. The mass, volume and water absorption rate of cooked dumpling shells decreased while the turbidity of cooked dumpling shells increased with the addition of WLL. L and b value of dumpling shells significantly decreased and a value of dumpling shells significantly increased because of increased amount of WLL contents. Hardness and adhesiveness of dumpling shells significantly increased in WLL2 and WLL3 groups. Cohesiveness, springiness, gumminess and chewiness of cooked dumpling shells were not significantly different according to the additions of WLL. In sensory evaluation, color, flavor, white lotus leaf flavor, taste and overall acceptability significantly increased in WLL3. Stickiness, softness, chewiness of cooked dumpling shells were not significantly different according to the additions of WLL. Overall, the result of this study indicates that the dumpling shell containing 3% WLL powder was most preferred among the groups.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.339-344
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• 2013

This study is conducted to investigate the shelf life of pork rectum stored at refrigerated temperatures (1, 5 and $10^{\circ}C$). The pH of the boiled pork rectum ($7.1{\pm}0.1$) was slightly higher than that of the raw pork rectum ($6.7{\pm}0.1$). TBA value of the boiled pork rectum was higher than that of raw pork rectum. The TBA values of the raw and boiled pork rectum stored at $10^{\circ}C$ was rapidly increased at 4 days after beginning of preservation. The TBA values of raw and boiled pork rectum stored at $5^{\circ}C$ rapidly increased after 8 and 6 days after beginning of preservation, respectively. VBN values of both raw and boiled rectum preserved at $10^{\circ}C$ were maintained below 20 mg% for 8 days since the beginning of storage. Furthermore, it is preferred that the pork rectum was boiled for 20 minutes at $100^{\circ}C$ to restrain mesophiles, psychrophiles, and coliform bacteria effectively. Thus, the most desirable condition was when the pork rectum was consumed within 6 days and stored at $10^{\circ}C$.

• Journal of the Korean Society of Food Culture
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• v.12 no.4
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• pp.391-400
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• 1997

To provide basic information for the development of refrigerated convenience foods for Koreans, 492 house-wives residing in Seoul and Kyunggi Province were surveyed concerning satisfaction of buying precooked convenience foods, frequency of using them, preferred Korean dishes, and willingness to buy the convenience foods if they are developed. Statistical data analysis was completed using SAS package program. The satisfaction mean score of the marketed precooked convenience foods was 2.73 out of 5 and the housewives were least satisfied with feed additives and sanitation factors. The factors affecting satisfaction in purchasing were sanitation, taste, variety of type, nutrition, price, and food additives for side-dishes sold refrigerated or at room temperature, and taste, sanitation, variety of type, price, nutrition, and food additives for frozen prepared foods in order respectively. The frequency of using the precooked convenience foods was generally low but that of using the pickled dishes, Jokbal Soondae, and frozen prepared foods was relatively high. The answer of 'the thought that meals should be prepared in households' was the primary reason for avoiding using the precooked convenience foods and 'no time to cook' was the most frequent answer among the reasons for using them. Currently, the precooked convenience foods were used for snacks mainly, but the usages to be expected to increase were for lunchbox, main dishes, snacks, side dishes, special occasions foods, and leisure foods in order. Based on preference and buying priority, the dishes needed to be developed as refrigerated convenience foods among Korean dishes were identified. The result showed that 'preference' was not consistent with buying priority and the housewives perceived the factor of 'convenience' more importantly than 'preference' in purchasing the convenience foods.