• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.239-245
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• 2004

Storage quality of minimally processed onion as influenced by hot-water dipping was investigated to examine feasibility of mild heat treatment as efficient post-processing method. fresh onions were peeled, trimmed, and dipped in hot water at various temperatures ($50-80^{\circ}C$) for 1 min. Heat-treated onions were cooled, de-watered, packaged in low density polyethylene (LDPE) film pouches ($63\;{\mu}m\;thickness$), and stored at $10^{\circ}C$. Samples treated at higher temperatures ($70-80^{\circ}C$) showed significant increases in flesh weight loss and discoloration during storage as compared to others. Hot-water dipping remarkably reduced initial microbial load of prepeeled onions, with over 1 log cycle decrease in aerobic bacterial count. After 7 days storage, no significant differences in viable aerobe count were observed among treated and untreated samples, with both showing $10^{6}-10^{7}\;CFU/g$. For sensory attributes including discoloration, wilting, decay, and visual quality, onions treated with hot-water dipping at $60^{\circ}C$ scored highest. Results suggested hot-water dipping at specific condition as practical post-processing treatment could effectively prolong shelf life of minimally processed onion.

• The Korean Journal of Pesticide Science
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• v.3 no.3
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• pp.60-67
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• 1999

Insecticidal activities of imidacloprid to sucking type insect pests, brown planthopper (BPH, Nilaparvata lugens) and peen peach aphid (GPA Myzus persicae), to chewing type insect pests, tobacco cut worm (TCW; Spodoptera litura) and beet armyworm (BAW, Spodoptera exigua) and to spiders, Pirata subpiraticus, Pachygnata clercki and Ummeliata insecticeps, as natural enemies were investigated by several bioassay methods. $LD_{50}$ of the chemical by topical treatment to BPH was 0.015 ${\mu}g/g$(48 hrs), while $LC_{50}s$ by leaf dipping and root zone treatment were 18.1 and 21.5 ppm, respectively. There was no difference in insecticidal activities between leaf dipping and root zone treatment. Imidacloprid also showed ovicidal effect of root zone treatment and its $LC_{50}$ was 6.8ppm $LD_{50}$ (48 hrs after treatment) of imidacloprid to GPA was $0.4{\mu}g/g$ in case of topical application and $LC_{50}s$ by leaf dipping and root zone treatment were 1.9 ppm and 13.7 ppm respectively. Leaf dipping was more effective than root zone treatment in GPA At topical application $LD_{50}$ (48 hrs after treatment) of imidacloprid to chewing type insect pests, TCW and BAW, were greater than 1,492 and $312{\mu}g/g$ and $LC_{50}s$ by leaf dipping method were 4,803 and Heater than 5,000ppm respectively. This means that imidacloprid has much less effect on chewing type insect pests, TCW and BAW. $LD_{50}$(48 hrs after treatment) of imidacloprid to wandering spiders, Pirata subpiraticus, Pachygnata clercki at topical application were greater dan $2941{\mu}g/g$ and greater than $2,976{\mu}g/g$ respectively and that to webbing spider, Ummeliata insecticeps, was 357 ${\mu}g/g$. Imidacloprid showed very low toxicity to the spiders and its selective toxicity ratios between spiders and BPH were greater than 19,600, greater than 19,800 and 23,800, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.796-802
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• 1995

Oyijangachi, a traditional Korean brinded cucumber, was prepared by brinning the cucumbers in five different solutions for 48 hrs and then, was dipped into dipping sources(Kochujang, Doenjang and Ganjang) for 30 days of aging. Firmness, calcium content and enzyme activities(pectinesterase and polygalacturonase) changes were measured among the cucumbers which were treated by five different solutions during aging. The firmness of Kochujang Oyijangachi were the lowest after 10 days of aging for all from the five brining solutions because of "hollow phenomena" of cucumbers. Calcium contents of cucumbers after dipping into the five solutiosn increased as calcium content of the solutions increased and also increased when the cucumbers dipped into the dipping bases(Kochujang, Doenjang and Ganjang) because of calcium migration from the dipping sources into the cucumbers during aging. The calcium contents of the three dipping bases were ranged from 70mg% to 120mg% of Ca. The activity of polygalacturonase in the Oyijangachi decreased generally during aging and decreased rapidly during initial 5 days of aging. The activity of pectinesterase of cucumbers treated with 12% salts solutions(treatment 3, 4 and 5) were higher than those of cucumbers treated with 6% salts solutions(treatment 1 and 2).

• Korean Journal of Plant Resources
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• v.15 no.1
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• pp.43-49
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• 2002

Effects of BA treatment and cut planting methods on shooting and seedling characteristics were investigated to increase seedling products by cuttings of lacquer tree. Dipping on 1,000mg/L BA solution was better than dripping with same solution at 5 weeks after cut planting. As shooting rate was increased suddenly, it was 85％ at 10 weeks after cut planting. Among 3 dripping treatments, interval was not effective on shooting rate. Dripping per 2 days with 100 ㎕ of 1,000 mg/L BA solution was most effective on seedling height and leaf number and than dipping was more effective than dripping per 5 and 7 days. Branch developed on near part from dripped scion. Shooting of horizontal planting was earlier about a week and rate was increased suddenly from 3 to 6 weeks, it was highest with 96％ than others at 10 weeks after planting. Seedling of horizontal cut planting was tallest about 40cm and branch developed lower than vertical and oblique cut planting. In case of horizontal cut planting, 2-3 shoots were formed on different part of scion and than those were could divided to seedling, so horizontal cut planting was most effective to propagation of seedling than any others.

• Korean journal of applied entomology
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• v.31 no.2
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• pp.182-189
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• 1992

The influnces of 9 kinds of solvents on the toxicities against several insect species, phytotoxicity and solubility of compounds were evaluated by means of leaf dipping and spray methods. In case of the spray application, density and vapor pressure seemed to be a contributing factor to lethal toxicity against brown planthopper and diamond-back moth, respectively; the bigger the property of density and the smaller the vapor pressure gave the stronger toxicity. It appeared that the toxicity of solvents was not correlated with anyone of physical properties such as boiling point, dipole moment, dielectric constant, surface tension and viscosity. Spray treatment gave more toxicity to insects than leaf dipping treatment. Although dielectric constant and dipole moment seemed to be contributing factors to phytotoxic damage to rice seedling and bean plants, respectively, no general correlation between phytoxicity and the other physical properties was found. Leaf dipping application caused stronger phytotoxicity than spray application. It is concluded that 5% acetone solution may be most suitable to test chemicals because of its favorable solubility of compounds, lower toxicity to insects, and lower phytotoxicity.

• Journal of the Korean Ceramic Society
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• v.35 no.9
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• pp.969-973
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• 1998

Pb(Zr, Ti)O3 (PZT) (Zr:Ti= 52: 48) thin films were prepared on MgO(100) substrates by dipping-py-rolysis process using metal naphthenates as starting materials. Thin films were fabricated by spin coating technique and the precursor films were prefired at 20$0^{\circ}C$ in air for 0.5, 1, 2, 3, and 24 h followed by final heat treatment at 75$0^{\circ}C$ for 30min. Film prefired for 24 h lost orientational properties and pole figure analysis showed the lost of the epitaxial relationship between the films and substrate while highly a/c-axis oriented thin films were obtained for the samples prefired for 1, 2, and 3h.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.6
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• pp.25-28
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• 2003

This study was conducted to development of rapid propagation method by leaf cuttings in Hibiscus hamabo native to southern seaside of Korea, and special object of this study was to determine the effects of IAA, IBA, and NAA on rooting in leaf cuttings of H. hamabo. Rooting was promoted by dipping treated with IAA and IBA. And rooting percentage was greatest at 1,000 and 2,000$mg{\cdot}L^{-1}$ IBA. At higher concentrations of IAA and IBA, more adventitious roots were developed. Also, IAA at high concentrations (above 2,000$mg{\cdot}L^{-1}$) and IBA ranged from 500~2,000$mg{\cdot}L^{-1}$ promoted on root number and rootingratio. However, root formation in Hibiscus leaf cuttings inhibited by NAA application.

• The Korean Journal of Food And Nutrition
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• v.11 no.6
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• pp.662-666
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• 1998

The effects of 0.5∼1.0% acetic acid, 0.5% laurice acid, or 0.5% monolaurine against Vibrio cholerae non 01 in flatfish strips stored at 15$^{\circ}C$ were assessed. Control strips were dipped in diatilled water only for 3 min. All treatments significantly (P<0.05) reduced the levels of V. cholerae at initial day. The counts of V. cholerae in flatifish treated with either lauric acid or monolurine were a significantly different (P<0.05) from those of acetic acid treatment after 2 days of storage. The counts of V. cholerae in treatments of 0.5% laurice acid after dipping in 1.0% acetic acid for 3 min were lower than those of treatments with 0.5% luarice acid for 3 min after dipping in 0.5% acetic acid for 3 min. Treatments with 0.5% monolurine for 3 min were not effective in lowering (P<0.05) the counts of V. cholerae after 3 days compared to the control.

• The Korean Journal of Ceramics
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• v.4 no.1
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• pp.33-36
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• 1998

Epitaxially grown $Bi_4Ti_3O_{12}$ thin films on the MgO(100) substrates was prepared by dipping-pyrolysis process using metal naphthenates as starting materials. The films annealed at various temperatures were charactrized by X-ray diffraction $\theta$-2$\theta$ scans and pole-figure analysis ($\beta$ scanning). Highly c-axia oriented Bi4Ti3O12 films were crystallized by heat-treatment at 700$^{\circ}$ and 75$0^{\circ}C$ from precursor films pyrolyzed at 50$0^{\circ}C$. The X-ray pole-figure analysis indicated that the $Bi_4Ti_3O_{12}$ thin films have an epitaxial relationship with the MgO(100) substrates.

• The Korean Journal of Ceramics
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• v.4 no.3
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• pp.199-203
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• 1998

$Pb(Zr, Ti)O_3$ (Pb:Zr:Ti=1:0.52:0.48) thin films were prepared on single crystal MgO(100) substrates by dipping-pyrolysis process using a solution of constituent metal naphthenates as starting materials. The solution was spin-coated onto substrate and the precursor films were pyrolyzed at $200^{\circ}C$ in air or at $200^{\circ}C$ in argon for 1, 2, 5 and 24h, followed by final heat treatment at $750^{\circ}C$. For all the films, highly (h00)/(00l)-oriented Pb$Pb(Zr, Ti)O_3$ thin films with smooth surfaces and crack-free were obtained, whereas thin film pyrolyzed in air for 24 h exhibited polycrystalline character. According to the pole-figure analysis, epitaxy of the product films was found to depend on pyrolysis atmosphere.