• Journal of the Korean Vacuum Society
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• v.17 no.5
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• pp.435-441
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• 2008

In this paper, we investigated the electrical properties of triisopropylsilyl (TIPS) pentacene organic thin-film transistor (OTFT) depending on solvent type. We spin coated TIPS pentacene by using chlorobenzene, p-xylene, chloroform, and toluene as solvents. Fabricated OTFT with chlorobenzene shows field-effect mobility of $1.0{\times}10^{-2}cm^2/V{\cdot}s$, on/off ratio of $4.3{\times}10^3$ and threshold voltage of 5.5 V. In contrast, with chloroform, the mobility is $5.8{\times}10^{-7}cm^2/V{\cdot}s$, on/off ratio of $1.1{\times}10^2$ and threshold voltage of 1.7 V. Moreover we measured the grain size of each TIPS pentacene solvent by atomic force microscopy (AFM). From these results, it can be concluded that a solvent with higher boiling point results in better electrical characteristics due to large grain size and high crystallinity of TIPS pentacene layer. In this paper TIPS pentacene with chlorobenzene shows the best electrical properties.

• Applied Biological Chemistry
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• v.15 no.3
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• pp.213-219
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• 1972

In order to utilize sweet potatoes for the material of Takju, brewing experiments with raw sweet potatoes, sweet potato chips powder and its koji were conducted; and various tests were carried out on effect of the treatments of acid, alkali, polyphenol oxidase inhibitor, oxidizing and reducing agents upon the prevention against coloring of sweet potato chips by steaming, and on peeling effect of sweet potatoes by the alkali and heat treatments. The results obtained were as follows. 1) In the case of brewing with raw sweet potatose, each plot showed low acid and ethanol content, and its finished Takju had an undersirable color and odor. The plots which were mashed after peeling showed higher ethanol contents than the plots mashed without peeling. 2) In the case of brewing with sweet potato chips powder, each plot contained considerably more amount of ethanol than the plots brewed with raw sweet potatoes, white it contained less amount of acid. The ethanol contents of the plots using wheat bran koji were $10.5{\sim}11.4$ per cent 4 days after mashing, and were higher than those of the plots using malts powder. Their finished Takju was inferior in quality because of the lack of acid and being darkened gradually in process of time. 3) The kojies which were made of sweet potato chips powder with Neurospora sitophila or Aspergillus oryzae had good appearance, but the Takju mashes brewed with these contained remarkably less amount of ethanol. 4) Effect of the treatments of acid, alkali, polyphenol oxidase inhibitor and organic solvents such as ether and ethanol upon the prevention against coloring of sweet potato chips was not recognized. Alum and burnt alum were effective a little on the decolorization, and among the oxidizing and reducing agents tested, potassium permanganate was most effective. 5) Darkening of sweet potato chips powder in course of heating after mixing with water was not affected by pectin and amino acids, but by tannin. 6) Sweet potatoes were not peeled easily by friction after soaking in the boiling solution of 3 per cent alkali for 6 minutes and peeled in boiling water for 12 minutes. From the viewpoint of the results above mentioned, it seems to be necessary to study further on the isolation of microorganisms which are able to decompose the coloring substances and yeasts which are adequate for the fermentation of sweet potatoes in order to utilize sweet potatoes for Takju brewing, because brewing with raw sweet potatoes, sweet potato chips powder and its koji was unsuccessful, and effect of the various treatments on the decolorization of sweet potatoes was not recognized.

• The Journal of Korean Society of Virology
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• v.26 no.2
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• pp.273-283
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• 1996

In order to search for anti-influenza virus type A agents from Korean traditional prescriptions (herb complexes), we selected 63 traditional prescriptions, based on a review of the Korean traditional medicine books. Both methanol extracts and boiling-water extracts were tested, by means of the Haemagglutination Inhibition Test (HIT). Three of the 63 methanol extracts: CM-22, CM-26, CM-48 (see explanation of nomenclature below), showed efficacy against influenza virus type ACM-22 showed anti-influenza virus type A activity at the range of $313{\mu}g/ml$ to $9.75{\mu}g/ml$, CM-26 showed antiviral activity at the range of $156{\mu}l/ml$ to $4.87{\mu}g/ml$, CM-48 showed anti-influenza virus type A activity at the range of $625{\mu}g/ml$ to $19.5{\mu}g/ml$, respectively. Three of the water extracts: CW-14, CW-34, CW-61 were active. CW-14 showed anti-influenza virus type A activity at the range of l0mg/ml to $78{\mu}g/ml$, CW-34 showed antiviral activity at the range of 10mg/ml to $625{\mu}g/ml$ and CW-61 showed anti-influenza virus type A activity at the range of l0mg/ml to $313{\mu}g/ml$, respectively. In order to determine cytotoxicity of each extracts, chicken red blood cells were incubated with the various concentration of extracts of Korean traditional prescriptions. CW-14, CW-34 and CW-61 did not show cytotoxic effect against red blood cells whereas CM-22, CM-26 and CM-48 showed cytotoxic effect against red blood cells at the range of l0mg/ml to $625{\mu}g/ml$, 10mg/ml to $313{\mu}g/ml$ and 10mg/ml to $313{\mu}g/ml$, respectively. These results indicated that Korean traditional pres criptions may be inhibit either attachment of virus to cell surface receptor or penetration of the virus into cell during the initial stage of infection.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.240-248
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• 1997

References on the cooking and processing losses of organophosphorus (OP) pesticides in foods were collected and analyzed to indicate that the average removal of whole pesticides being 45% in water washing, 56% in detergent washing, 91% in peeling of fruits, 5l% in blanching-boiling of vegetables, 90% in milling and processing of grains. The theoretical maximum daily intake (TMDI) calculated from the food intake and Korea maximum residue limits showed that 4 among 11 pesticides exceeded the acceptable daily intake (ADI). The estimated daily intake (EDI) calculated from the food intake and monitoring data reached 17.2% of ADI on the assumption that the toxicity of OP pesticides appears as an additive effect. The % ratio of ADI for individual pesticides was 6.1% in diazinon, 5.8% in fenthion, 3.3% in fenitrothion and very low in other pesticides. By applying reduction factors to the EDI, the removal ratio of OP pesticides in cooking and processing appears to be over 50%. In summary, the exposure level of Korean population toward whole OP pesticides was estimated to reach 23% of ADI, which would not cause any health rick as yet, but calls for a systematic risk assessment.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.292-301
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• 1997

In drying process, to minimize the quality degradation by improved drying process and pretreatment methods, carrots, cabbages and radishes were dried and rehydrated. Physico-chemical properties of product were analyzed to determine the optimum pretreatment method and drying models were applied to explain drying mechanisms. Microwave, steam and water were used prior to drying as blanching method. In consideration of physical properties, optimum treatment time was decided that microwave was 1 min, steam and water were each 10 min. Control, steam, water, microwave and osmotic dehydration were treated prior to drying as pretreatment individually, osmotic dehydration was lower than the other treatmemt in drying efficiency, but carotene content was higher than the others. The effect continued after rehydration. Ten panelists tested dried and rehydrated carrots. After rehydration, the quality of air dried product with osmotic dehydration was superior to freeze dried without treatment. The fittness of drying models were conducted in order to explain the mechanism of drying each process. Quadratic model was most fittable to explain during drying. However, in rehydration process, no fittable model was found.

• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.26-30
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• 1994

The purpose of this study was to investigate the effects of heating times of soy protein isolate(SPI) and mixing ratio of coagulants mixture on water holding capacity(WHC) and oil absorption capacity (OAC) of SPI, texture properties and yield of tofu. The effect of heating at $100^{\circ}C$ on the amounts of coagulants required for coagulation showed that the amounts of $CaCl_{2},\;MgCl_{2}$ and GDL decreased as the heating time extended to $6{\sim}9$ minutes while $CaSO_{2}$ was changed little. The tofu yield showed maximum for the tofu prepared by 6 minutes boiling and coagulation with $CaSO_{4}$. The WHC of SPI was significantly reduced by heating at $100^{\circ}C$ while OAC was rather increased until 9 minutes of heating. The textural properties of SPI tofu coagulated with mixed coagulants$(CaSO_{4}-GDL,\;CaSO_{4}-CaCl_{2},\;CaCl_2-GDL)$ showed that softer tofu was obtained as the ratio of $CaSO_{2}$ increased and harder tofu as the ratio of $CaCl_{2}$ and GDL increased. The maximum and minimum tofu yields were prepared from 100% of $CaSO_{2}$ and 100% of GDL, respectively. Organoleptic properties showed that more uniform and tender tofu were obtained with higher portion of $CaSO_{2}$ in the mixed coagulants and higher intensity of sourness and bitterness were scored as the GDL and $CaCl_{2}$ added more.

• The Journal of the Korean bone and joint tumor society
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• v.2 no.1
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• pp.18-26
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• 1996

We investigated the effect of deep-freezed, boiled and autoclaved autogenous long bone graft on the incorporation of the radial diaphyseal reconstruction in 30 rabbits by radiogram and histology for 8 weeks. Immediate histologic changes of 1cm of resected long bone treated by deep freezing, boiling and autoclaving in each 2 rabbits were also observed as control. Resected, boiled ($95^{\circ}C$ for 5 min.) and reimplanted bone was compared with resected, autoclaved ($131^{\circ}C$ for 5 min.) and reimplanted bone, and resected, deep freezed with liquid nitrogen for 5 minutes and thawing in saline and reimplanted bone in the reconstruction of bilateral radial defects in each of 8, and in total 24 adult rabbits. The results were as follows : 1. Immediate histologic changes showed that intracortical osteocytes in lacunae were partially necrotized and the cortex were faintly stained with they Masson trichrome stain in both boiled and deep freezed groups, while they completely necrotized and their cortex stained more weakly with Masson trichrome stain in autoclaved group which means less amount of collagen and protein in cortex of long bone. 2. Radiographies at 8 weeks showed complete union with more marked incorporation and external callus formation in all boiled and freezed groups, whereas there was delayed union in four of sixteen (25%) in autoclaved group. Histologically, at 8 weeks after boiled and freezed, more intense incorporation with new bone formation and neovascularization were observed, whereas transverse clefts consisted with delayed union in 4 cases of autoclaved group (25%) were observed at osteotomy site. Through these studies, the boilod and deeply freezed bones acted as an osteoinductive material as well as osteoconductive, but the autoclaved bone only as osteoconductive. Though boilod and deeply freezed bone showed higher osteogenic potentials than autoclaved bone, the necrotizing effect on cortical and boiled bone was inferior to that of autoclaved. Thus the deeply freezed bone can be used for the treatment of aggressive benign or less malignant bone tumor not involving cortical bone, but the autoclaved bone supplemented with bone graft for the treatment of malignant bone tumor involving cortex of long bone.

• Journal of Sericultural and Entomological Science
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• v.31 no.2
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• pp.91-101
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• 1989

This experiment was carried out to analyze genetic parameters for the selection of silkworm by diallel-crossing with three Japanese and four Chiness silkworm races. Heritability, genetic correlation and path coefficient were calculated as the statistical parameters to evaluate direct or indirect effects of various gentic characters on bave weight. The heritabilities of fifth instar period, cocoon weight, cocoon layer weight, cocoon layer ration, fibroin contents, boiling off ratio and bave weight were over 76.65% in both F1 and F2 generations. There were positive coefficients in both phenotypic and genotypic correlations between male and female of both F1 and F2 generations. The latter showed greater values in general. The correlation between bave weight and the characters of cocoon weight, cocoon layer weight, cocoon layer ratio, fibroin contents were over 0.727 in both sexes of F1 and F2. Therefore, these results suggest that above characters would be useful for genetic selection of silkworms. As result of path coefficient analysis, there was a direct effect with path coefficient value of 0.991 between bave weight and F1 female cocoon layer weight, and with the value of 0.803 between bave weight and F1 male cocoon weight. In F2 the effect showed 0.938 between bave weight and male cocoon weight and cocoon layer weight had greater influence on direct or indirect effects (in path coefficient) than the others.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.348-355
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• 2008

Recently, an understanding of new sources of liquid hydrocarbons such as bio-ethanol is economically very important. The present dissertation is also designed with purpose of developing the energy-saving process for the separation of bio-ethanol. In order to illustrate the predictability of proposed process for the separation of bio-ethanol, the experimental data from literatures and real plant data are used. Application of the thermodynamics of multicomponent mixtures and phase equilibria to the extractive distillation process with syntheses of heat exchanger network has enabled the development of energy-saving process for different separating agents. Developed process is capable of minimizing the energy usage and the environmental effect. This extractive process is also able to properly describe the effect of impurities, the choice of separating agent. Simulation results of extractive distillation using ethylene glycol show that impurities do not affect to extractive distillation operation and agent, ethylene glycol, was recycled without any loss. It is possible that extraction distillation has various heat network for anhydride ethanol and recovery of ethanol is maximized. Ethylene glycol as separating agent has a high boiling point to eliminate azeotropic point and on the contrary solubility of agent is low to be almost completed recovered. Proposed process is also the energy efficient process configuration in which 99.85mole% anhydride ethanol can be produced with low energy of 1.37198 (kg steam/kg anhydride ethanol).

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.1
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• pp.155-159
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• 2016

The objective of this study was to investigate the effect of fermentation temperature on quality characteristics of apple wine. Apple wine mashes were fermented in 15, 20, and $25^{\circ}C$ water bathes for 9 days. The pH levels of all samples were below 4 from 24 h of fermentation until the end. Total acidities of 0.05% acetic acid solution were 7.8, 7.4, and 7.0% in the 15, 20, and $25^{\circ}C$ fermented samples, respectively. The evaporation of esters generated by combining alcohol and organic acids might be the reason for lower total acidity for high temperature fermentation. Alcohol contents of the 20 and $25^{\circ}C$ fermented samples were 6.5 and 6.6% (v/v), respectively, whereas that of the $15^{\circ}C$ fermented sample was 5.6% (v/v) and significantly lower than the others (P<0.05). Methanol contents were 0.68, 0.82, and 1.69 mg/L in the 15, 20, and $25^{\circ}C$ fermented samples, respectively. Fermentation at higher temperatures generated higher methanol content in apple wine. On the other hand, acetaldehyde contents were 3.43, 2.39, and 1.02 mg/L in the 15, 20, and $25^{\circ}C$ fermented samples, respectively, due to the lower boiling point of acetaldehyde ($20.2^{\circ}C$). Based on the results, a fermentation temperature of $20{\sim}25^{\circ}C$ is effective for apple wine fermentation.