• Journal of Environmental Science International
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• v.26 no.1
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• pp.47-54
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• 2017

We analyzed the variation in occurrence time and intensity of attacks by the rice stem borer (Chilo suppressalis Walker) on several crops. This study aimed to understand how C. suppressalis damages crops and to utilize this basic data for the establishment of environment-friendly control methods like pheromone traps. This study surveyed the changes in occurrence patterns of C. suppressalis, biological characteristics of overwintering larvae, and the efficacy of different types of pheromone traps the years. We found similar occurrence patterns of C. suppressalis in different crops. In addition, occurrence time of the first generation was advanced. Overwintering larvae showed no difference in pupal period and weight compared to the non-overwintering ones. However, the larval period was reduced to 19.1 days in Miscanthus field, in contrast to that in the paddy fields. It was confirmed that larvae of C. suppressalis generally prefer the lower part of the stems of Miscanthus. Efficiency of the emergence trap was confirmed to be greater than that of the delta trap for capturing C. suppressalis adults. However, it is necessary to adjust the control period because of the advancement in occurring time of C. suppressalis in recent years. The larvae of C. suppressalis experience favorable environmental conditions for overwintering in Miscanthus fields. The major Miscanthus fields are generally located in the areas protected for sources of drinking water, owing to which spraying of chemical pesticides is very limited. The results of this study provide important inputs for the development of environment-friendly control methods.

• Journal of Food Hygiene and Safety
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• v.12 no.1
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• pp.26-38
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• 1997

The quality changes of hams and sausages in refrigerated storage were investigated. Seven types of hams and six types of sausages produced in Korea were collected from markets and stored at 1$0^{\circ}C$ according to the Food Code of Korea, and then chemical, microbiological, textural and sensory characteristics were evaluated at 30, 40 and 50 days. The proximal analysis showed considerable variation in fat with less variation in moisture and protein. The pH values of hams and sausages slightly changed with no consistent difference. Water activity values of all samples except one type of sausage were consistent over time in refrigerated storage. No purge losses of hams were observed except two types of samples in the intial stage. Several types of sausages showed purge losses with no consistency and one type of sausage showed consistent purge losses (0.44~11.29%) during the storage. The volatile basic nitrogen (VBN) content of hams and sausages was still within 20 mg% (Standard and Specification of Korea) on the 50th day, although the VBN of all samples significantly increased over time (p<0.05). The thiobarbituric acid (TBA) values of hams and sausages were well below 1.0 during the storage, although the TBA values of all samples significantly increased (p<0.05). However it was noticed that one type of ham and two types of sausages showed TBA values of 0.945, 0.928 and 0.978, respectively. All the standard plate counts (SPCs) of hams during the storage period showed a level below 30 CFU/g except one type of sample with 103 CFU/g at 50 days. All the SPCs of sausages showed a level below 50 CFU/g except one type of sample with 102 CFU/g and two types of samples with 104 CFU/g on the 50th day. Coliform groups were not counted in all samples during the storage. Instrumental texture analysis showed that springiness, cohesiveness, chewiness, gumminess and adhesiveness slightly changed with no consistent difference. The hardness of the hams showed a decreasing tendency, and the hardness of the sausages an increasing tendency with no significant difference. Sensory evaluation for color, flavor, taste, texture and overall acceptability showed decreasing tendencies over time (p<0.05). The scores of the five sensory characteristics maintained the medium level of quality at the termination of the experiment. Although the results indicated that the ham and sausage samples were acceptable after the 50 days' storage at 1$0^{\circ}C$, the shelf-life of the samples should be determined considering the rapid growth of bacteria and the high TBA values at 50 days.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.3
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• pp.280-287
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• 1997

This study was carried out to investigate agricultural status and soil fertility of Bonghwang-cheon watershed area which is located at Chodong-myeon, Milyang-si. The acreage of arable land was about 1,209ha, and the population was 3,706 people. Out of total arable land, paddy was 64.4%, upland 19.6% and orchard 16.0%. Chicken was the largest in the number of livestock and poultry, but pig seems to contribute most severly to water pollution. The geology in the lower stream was alluvium but andesite and derivated materials from it were occupied most upland areas. Tuff was scattered in the small area near by the alluvium of Nakdong river, and diorite and granodiorite were located at the low hill and mountains respectivately. The principal paddy soils in the area were Geumgog, Jisan and Imgog series etc of fine loamy on sloped valleys and fans. The Pyeongtaeg series, fine silty family of imperfectly drained on plain was irrigated by Chodong reservoir. The clayey Honam series on alluvium was distributed along the low hill while Gyuam series, coarse silty alluvial soil way close to Nakdong river. In chemical properties of soils, the vinyl house soils were higher in EC, and orchard soils in OM, $P_2O_5$, exchangeable canons than other soils.

• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.105-111
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• 2012

Manganese (Mn) catalysts were generated using $CeO_2$ and $ZrO_2$supports synthesized by the supercritical hydrothermal method and two different Mn precursors, aimed at an application for a low-temperature selective catalytic reduction process. Manganese acetate (MA) and manganese nitrate (MA) were used as Mn precursors. Effects of the kind and the concentration of the Mn precursor used for catalyst generation on the NOx removal efficiency were investigated. The characteristics of the generated catalysts were analyzed using $N_2$ adsorption-desorption, thermo-gravimetric analysis, X-ray diffraction, and X-ray photoelectron spectroscopy. De-NOx experiments were carried out to measure NOx removal efficiencies of the catalysts. NOx removal efficiencies of the catalysts generated using MA were superior to those of the catalysts generated using MN at every temperature tested. Analyses of the catalyst characteristics indicated that the higher NOx removal efficiencies of the MA-derived catalysts stemmed from the higher oxygen mobility and the stronger interaction with support material of $Mn_2O_3$ produced from MA than those of $MnO_2$ produced from MN.

• Applied Chemistry for Engineering
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• v.25 no.4
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• pp.380-385
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• 2014

Spherical atomizing reduction steel slag was prepared by atomizing technology using reduction steel slag (ladle furnace slag, LFS) generated from steel industry. In order to develop the mass-recycling technology of atomizing reduction steel slag, polymer concrete composite was prepared using spherical atomizing reduction steel slag instead of fine aggregate (river sand) and coarse aggregate (crushed aggregate), depending on the grain size. Different polymer concrete specimens were prepared with the various proportions of polymer binder and replacement ratios of atomizing reduction steel slag in order to investigate the characteristics of polymer concrete composite. Results showed that compressive strengths of polymer concrete specimens decreased with the increase of replacement ratios of atomizing reduction steel slag, but flexural strengths of the specimens showed a maximum strength at the 50% of replacement ratios of atomizing reduction steel slag. It was concluded that addition ratio of polymer binder, which affect greatly on the prime cost of production of polymer concrete, could be reduced by maximum 18.2 vol% because the workability of the polymer concrete was remarkably improved by using the atomizing reduction steel slag. However, further study is required because the mechanical strength of the specimen using atomizing reduction steel slag was greatly reduced in hot water resistance test.

• Journal of the Korean Geotechnical Society
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• v.30 no.7
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• pp.5-15
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• 2014

Abandoned mine deposits are exposed to various physico-chemical geo-environmental hazards and disasters, such as acid mine drainage, water contamination, erosion, and landslides. This paper presents the ring shear characteristics of waste materials. The ring shear box with a rotatable O-ring was used in this study. Three tests were performed: (i) Shear stress-time relationship for given normal stress and shear speed, (ii) shear stress as a function of shear speed, and (iii) shear stress as a function of normal stress. For a given normal stress (50 kPa) and speed (0.1 mm/sec), the materials tested exhibit a strain softening behavior, regardless of drainage condition. The peak and residual shear stresses were determined for each normal stress and shear speed. The shear stress was measured when shear speed is equal to 0.01, 0.1, 1, 10, 50, 100 mm/sec or when normal stress is equal to 20, 40, 60, 80, 100, 150 kPa. From the test results, we found that the shear stress increases with increasing shear speed. The shear stress also increases with increasing normal stress. However, different types of shearing mode were observed in drained and undrained conditions. Under drained condition, particle crushing was observed from the shearing zone to the bottom of lower ring. Under undrained condition, particle crushing was observed only at the shearing zone, which has approximately 1 cm thick. It means that a significant high shear speed under undrained condition can result in increased landslide hazard.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.91-95
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• 2009

To examine physico-chemical properties of the polysaccharide extracted from liquid-cultured mycelia of Schizophyllum commune, each the polysaccharide was extracted with hot water treatment and then fractionated with ethanol, alkaline solution and ultrafiltration. And we determined carbohydrate contents, composition of amino acids, infra-red spectrum and viscosity. Carbohydrate contents of polysaccharide treated with ethanol and ultrafiltration were 72.0% and 62.3%, and proteins content were 15.3% and 32.0% respectively. The carbohydrate consisted of four monosaccharides and the protein contained 16 amino acids. The polysaccharide obtained from ultrafiltration was shown an absorption band characteristic of the ${\beta}$-glycosidic linkage by infra red spectra. These results suggest that the polysaccharide extracted from Schizophyllum commune showed the characteristics of proteinbounded polysaccharide, and it was ${\beta}$-glycosidic linkage with strong viscosity.

• Food Science and Preservation
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• v.22 no.3
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• pp.385-391
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• 2015

This study was conducted to develop a spray-dried garlic chives (Allium tuberosum) powder and to evaluate its quality characteristics depending on the treatment of steam blanching pretreatment $100^{\circ}C$, 3 min) and the addition of forming agents (dextrin (DE=10), ${\beta}$-cyclodextrin) during process. The steam blanching pretreatment showed an increase in $L^*$ value while a decrease in $-a^*$, $b^*$, $C^*$, and $h^o$ values of the powder. Moisture content and water soluble index were not affected by the treatment of steam blanching and the addition of forming agents, whereas the particle diameter was the smallest in the steam blanching treatment and dextrin addition. Chlorophyll, phenolic compound, and vitamin C content, and DPPH radical scavenging activity of non-pretreated powder were significantly higher than those of the steam blanching treated powders. However, there was no significant difference between the two forming agents. The sensory acceptability (color, smell, and overall acceptability) of powder treated with steam blanching were significantly higher than those of non-pretreated powders. Therefore, the steam blanching pretreatment of fresh garlic chives affected on the better quality characteristics of the spray-dried powders when compared with non-pretreated powder though it adversely affected the natural chemical quality of fresh garlic chives.

• Culinary science and hospitality research
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• v.18 no.5
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• pp.243-255
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• 2012

This research has been conducted to develop the best recipe for brown sauce containing freeze-dried Salicornia powder. For this purpose, we made brown sauces with different contents of freeze-dried Salicornia powder and performed physico-chemical characteristic and sensory test. The highest salinity of freeze-dried Salicornia powder was 0.15% when 1% freeze-dried Salicornia powder was added to distilled water, SP1. The highest brightness of brown sauce was achieved with 1.2% freeze-dried Salicornia powder and was 45.29 with BSP12. More powder led to significant increases of the samples(p<0.001) in salinity and brightness. DPPH radical scavenging increased with greater freeze-dried Salicornia powder. Taste was highest at 6.36 with 0.6% powder and there was no significant difference compared to BSP6 and BSP9. Based on these findings, it was concluded that the brown sauce with Salicornia has antioxidative characteristics and the best salinity is achieved with 0.6% freeze-dried Salicornia powder. Salicornia had enough salinity to substitute salt to a certain degree and improved the quality of brown sauce in terms of the sensory test.

• Korean Journal of Plant Resources
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• v.30 no.4
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• pp.372-377
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• 2017

This research was performed to develop mass propagation method of Alpine modest primrose (Primula modesta var. hannasanensis T.Yamaz.) for improving the conservation and utilization of the species. Seeds were collected on August 2011 in Jeju-city and well-selected seeds were dry-stored at $4{\pm}1.0^{\circ}C$. Seed size ranged $0.44{\pm}0.07{\times}0.61{\pm}0.04mm$, and weight of 1,000 seeds was $51.78{\pm}0.021mg$. Thus the seed was classified as 'dwarf seeds'. As the result of dormancy characteristics, moisture content of freshly matured seeds increased rapidly by water-soaking treatment and seeds did not germinate at $20^{\circ}C$ for 4 weeks under the light condition. Therefore, seeds were estimated to have physiological dormancy. Germination conditions of dry-stored seeds were found to be $20^{\circ}C$ and light condition, and seeds did not germinated under dark condition regardless of all temperature regimes. Therefore, Alpine modest primrose seed was considered as photoblastic type. Percent germination (PG) and germination energy (GE) were greatly improved by soaking the seeds in $GA_3$ and kinetin for 24 hours. Especially, 200~500 mg/L $GA_3$ treatment resulted in the highest PG (95.5%) and GE (98.3%). So, chemical treatment such as $GA_3$ was thought to be a useful method for raising seedling uniformly.