• Korean Chemical Engineering Research
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• v.40 no.6
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• pp.729-734
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• 2002

In this study, the polyaniline films of emeraldine base(EB) and lucoemeraldine base(LEB) form chemically doping with poly(sodium-4 styrenesulfonate, PSS) were prepared by casting the mixed solution of chloroform and m-cresol on ITO(indium tin oxide) electrode. By analyzing UV-vis spectra of the mixed solutions, the effects of the secondary doping by m-cresol were obtained. And the conductivity of polyaniline film was increased with increasing m-cresol content. The results suggest that the improvement of conductivity obtained by secondary doping results primarily from interaction of polyaniline and m-cresol. As the results of analyzing cyclic voltammograms, it was known that the redox peak currents of polyaniline electrode prepared from LEB were larger and more reversible than those of polyaniline electrodes prepared from EB. The charge transfer resistances($R_{ct}$) of polyaniline electrodes were reduced with increasing m-cresol content, and LEB/PSS electrodes were smaller than EB/PSS electrodes. This result agrees to the analysis of the redox peak current of cyclic voltammograms. The solution resistance and the capacity of electrical double layer almost unchanged in all prepared polyaniline electrodes. It was confirmed that solution resistance was independent of frequency factor in AC impedance spectra. Also the polyaniline film doping with PSS was revealed pseudo n-type characteristics of conducting polymer.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.1
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• pp.1-6
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• 2018

This study was conducted to investigate the feed value and silage quality according to storage period and film layers in whole crop oat silage. The crude protein content was increased in all silage during the storage periods compared to those before silage, under prolonged storage period slightly and the number of film layers of silage, six layer were higher than four layers, but no significant. NDF and ADF contents were also increased in all silage of storage duration compared to those before silage, but they was similar level between storage duration and number of film layers. TDN content was decreased of the storage duration. However, it was similar under the storage duration and the number of film layers. The pH value was decreased during prolonged storage period and six layers was lower than four layers depending on the film layers. In the organic acid contents, lactic acid and acetic acid were increased under the prolonged storage duration, and butyric acid was higher significantly(p<0.05), six layers of the film were showed higher lactic acid and lower butyric acid(p<0.05). Therefore, oat silage should be used within 6 months it was when treated with 4 layers, if considering the long-term storage, it is desirable to treat it with 6 layers or more.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.61-68
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• 2011

Loperamide-induced constipation reduced gastric emptying, small-intestinal and colonic motility, and these effects were prevented by Actindia chinensis(Gold Kiwi Fruit, GKF). In this study, the effects of Actindia chinensis on constipated male Sprague-Dawley rats induced by loperamide(2 mg/kg, s.c.,5 days) were investigated. Rats were randomly assigned to the normal control rats(regular diet), constipated rats(regular diet plus loperamide), constipated rats treated with 2.5% GKF(regular diet supplemented with 2.5% GKF plus loperamide), constipated rats treated with 5% GKF (regular diet supplemented with 5% GKF plus loperamide). There was less fecal excretion and lower fecal water content in loperamide-treated rats than in control rats. Oral administration of GKF blocked the decrease of fecal excretion and fecal water content in the loperamide-treated rats. Mucus production of crypt cell and mucus contents at fecal and mucosa surface were reduced by loperamide-treated rat. But colonic crypt cell contained increased mucin in the GKF treated group and mucus layer stained with alcian blue was significantly thicker in GKF treated rats compared with in loperamide-treated rats. In isolated rat ileum, loperamide produced inhibition of ileal motility. Pretreatment with methanolic extracts of GKF in isolated rat ileum prevented inhibition by loperamide. These findings indicated that the GKF was effective for alleviation of inhibition of colonic peristalsis by loperamide and that GKF might be of value in the prevention of constipation.

• Food Science of Animal Resources
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• v.33 no.2
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• pp.251-257
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• 2013

To evaluate the effects of surimi substitution to spent laying hen crushed breast meat on the quality of the Cremi during storage, this study was conducted. Spent laying hen breast meat was crushed using a silent cutter, which is normally adapted to the sausage process. The Cremis were manufactured by the addition of 5 or 10% CSBM and separated to three different groups including control and 5 (05CM) and 10% crushed meat (10CM) treatments. All cremis were packaged and stored at $10{\pm}1^{\circ}C$ for 3 weeks, and the analysis for the determination of physicochemical and sensory properties of cremi was conducted on week 0 and 3 of storage only. Moisture content was significantly differed depending on storage days and both 05CM and 10CM had high moisture content as compared to that of control (p<0.05). In addition, TBARS was lowered when surimi was substituted up to 10% CM as compared to cremis manufactured by the addition of 5% CM. The cremis sampled from 05CM and 10CM treatments had low in CIE $a^*$, in contrast showed high in CIE $b^*$ than control (p<0.05). The substitution of surimi to CM did not influence on sensory characteristics even though shear force and gel characteristics were affected (p<0.05). In conclusion, the results indicate that although significantly lowered shear force and gel characteristics were determined in 05CM cremis (p<0.05), trained sensory panels did not recognize the differences of 5 or 10% CM addition. Therefore, it seems that the substitution of surimi up to 10% CM may be secured and economically considerable.

• Journal of Conservation Science
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• v.32 no.4
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• pp.549-560
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• 2016

The purpose of this study is to identify the material characteristics of blackwares excavated from the Bonggok kiln site in Jinan-gun, Jeollabuk-do Province, South Korea, by scientific analyses and a reproduction experiment. Scientific analyses were conducted to determine the physical properties, chemical composition and for microscopic observation of blackwares. A reproduction experiment was also conducted by producing ceramic samples with black glaze, red ocher and limestone, and then cross sections of the samples were observed. The analysis results showed that all the excavated blackwares have similar properties such as chromaticity, specific gravity, absorption factor and porosity, but there is a difference depending on the crystallization of the ceramics. Thermal analysis showed that the exothermic peak was observed at about $1200^{\circ}C$, and crystal structure analysis indicated the presence of mullite. Hence, it can be concluded that the firing temperature of the excavated blackwares was around $1100-1200^{\circ}C$. Moreover, the glaze present on these blackwares has about 22% higher $Fe_2O_3$ content than those excavated from other places; however, the former has lower CaO content. For the reproduction experiment, samples were made using limestone as a flux and red ocher as a glaze. The results show that the cross section of the glaze layer of the reproduced sample have iron crystals with dendritic structures, similar to those present in the excavated black-wares. It is assumed that such iron crystals were formed during the process of melting and solidification of the iron oxide present in the blackwares.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.3
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• pp.245-253
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• 2001

To investigate the effects of hydromechanical and textural characteristics of sediment deposits on the cultivation of Manila clam, Ruditapes philippinarum surface and sub-surface core sediments were collected seasonally in Gomso tidal flat. Grain size distribution were analyzed to investigate the annual variation of sediment texture. In winter unimodal distribution of grain size with the peak at $5\phi$ is dominant However, during the summer sediment texture become a little bit coarser and grain size distribution shows the peaks at $4\~5 \phi$. Optimum sediment texture for the cultivation of manila clam, R. philippinarum was found to be sandy silt in which mean Brain size was between 4 and $5 \phi$ with the sand content less than $50\%$ and clay content of $5\~10\%$. Mechanical and hydrological characteristics of sediment deposits were also studied in the laboratory and the results were applied to the numerical simulation for the behavior of surface sediment subjected to the cyclic loading from sea-water level change. Results of numerical simulation illustrate that the permeability of sediment had to be maintained in the range of $10^{-11}\sim10^{-12}m^2$ to ensure the proper sedimentological environment for the cultivation of manila clam, R. philippinarum. The deposits of virtually impermeable mud layer, with the threshold thickness of 4 cm, would be very hazardous to clam habitat.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.424-430
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• 2002

Vas deferens is a long tube and could be divided into four regions as its morphological characters: a short and slender proximal region, a convoluted region, a straight and more thick distal region, and an ejaculatory duct, It is connected with the posterior outer horns of the testis and runs to the gonopores opened on the coxa of the fifth walking legs, The proximal region consists almost entirely of simple cuboidal epithelial cells, $12\~28{\mu}$m in height, surrounded by a thin basal membrane. A small aggregation of high cuboidal epithelium is obsened from one side of the proximal region. The convoluted and distal region is composed of two kinds of epithelial cells; high cuboidal epithelial cells, $40\~120{\mu}m$ in height located in dorsal portion and simple cuboidal epithelial cells of $12\~28{\mu}$m in height located in ventral and lateral portion. The ejaculatory duct is surrounded with two kinds of muscle layers, inner longitudinal and outer circular muscle fibers, The lumen is lined with high and simple cuboidal epithelium in almost equal proportions. The proximal region contains mature sperm and basophilic substances. The eosinophilic substances appeared newly going toward the convoluted region and are laid along simple cuboidal epithelial cell layer. Tube-like content (spermatophore) of the vas deferens is ejaculated from a pair of genital pores at mating. Two masses of the content fuse together side by side and are usually deposited on the female thorax between the second and fourth or fifth pereiopods, The spermatophore formed measures $2.7\~4.0$ mm in length and $1.5\~2.7$ mm in width.

• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.68-80
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• 1987

This study was carried out to investigate the evapotranspiration and variations of soil moisture contents for soybeans. The relationship between actual evapotranspiration obtained by the water balance equation and estimated evapotranspiration obtained by the soil moisture model was analyzed. The results obtained were summarized as follows; 1. The total amount of actual evapotranspiration of soybeans during growing season was 405.7mm. The total amount of reference crop evapotranspiration of soybeans that was estimated by Pan evaporation and Hargreaves method were 547.8 mm and 586.8 mm, respectively. Crop coefficient during growing season were shown on Table 1. 2. Measured actual evapotranspiration of soybean during growing season was 405.7 mm and estimated actual evapotranspiration by pan evaporation and Hargreaves method were 424.7 mm, and 426.1mm, r3 respectively. 3. The variations of soil moisture content for soybeans were high at 10cm layer, as compared with those at 30cm and 50cm layers. Because discrepancy between the variations of soil moisture content predicted by model and observed by soil moisture meter was still great, it is required to study the consumptive types of soil moisture at each root depth.

• Food Science and Preservation
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• v.22 no.1
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• pp.1-11
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• 2015

Raspberries are a good resource of polyphenols and have a powerful antioxidant activity, but shelf life for raspberries is short which brings a lot of economic losses. In this study, we try to use cool-air ($20{\sim}40^{\circ}C$) or hot-air ($60{\sim}100^{\circ}C$) to produce semi-dried raspberries with extended shelf life, and to determine the best method for improving fruit quality by minimizing nutrient losses during drying processes. The effects of process variables (drying temperature and processing time) on the quality of final dried raspberries were investigated. Response surface methodology was employed to establish statistical models for simulating the drying processes, and the moisture residue content and the loss ratios of total phenolic content (TPC), vitamin C (VC), and ellagic acid (EA) that result from the drying processes of raspberries using either hot or cool-air were predicted. Superimposed contour plots have been successfully used in the determination of the optimum zone within the experimental region. Optimal conditions determined for achieving minimal losses of TPC, VC, and EA, and a final moisture residue of 45% using the hot-air drying process were a drying temperature of $65.75^{\circ}C$ and a processing time of 4.3 hr. While for the cool-air process, the optimal conditions predicted were $21.3^{\circ}C$ and 28.2 hr. Successful application of response surface methodology provided scientific reference for optimal conditions of semi-drying raspberries, minimizing nutrient losses and improving product quality.

• Resources Recycling
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• v.26 no.2
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• pp.56-65
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• 2017

This study is an experimental study on the corrosion protection performance according to the configuration ratio of the Zn and Al. A metal spraying was used as the arc metal spraying method, a specimen was produced by varying the proportion ratio and coating thickness of the Zn and Al. Experimental methods visually observed to corrosion of the specimen for 1, 3, 7, 15 days was conducted in accordance with the CASS salt spray test. This study has confirmed that the performance of the corrosion protection improved against the increase in the Al content. Further, it was confirmed that excellent perfomance is exhibited when the coating thickness is secured over $80{\mu}m$. In addition, the SEM analysis was performed to observe the cross-sectional shape of the metal spraying specimen after CASS testing. The analysis result showed that the deterioration of the metal spraying coating layer was reduced as the Al content increases.