• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1798-1804
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• 2012

To prolong the shelf-life of domestic peaches, samples were treated with UV-C (0~10.0 $kJ/m^2$) and the spoiling rate and changes in physico-chemical and sensory properties were investigated. No spoiled peaches were observed within the first four days of storage in the control and 2.5 $kJ/m^2$ UV-C treatment groups. However, spoilage was observed in these groups on day six, and 29.17% and 25.0% of the samples showed spoilage on 10 day, respectively. Moreover, samples treated with greater than 5.0 $kJ/m^2$ of UV-C showed a higher percentage (41.67% or higher) of spoilage than those of the control or 2.5 $kJ/m^2$ UV-C treatment groups on 10 day. Additionally, weight changes in the peaches were the lower in the control group and 2.5 $kJ/m^2$ UV-C treatment group than in those treated with 5.0 $kJ/m^2$ of UV-C treatment or higher during 10 days of storage. There was no difference in pH among treatments, regardless of storage time. The hardness of the samples was not changed immediately after UV-C treatment, but that of samples treated with 5.0~10.0 $kJ/m^2$ of UV-C decreased rapidly after four days, when compared to the control and 2.5 $kJ/m^2$ UV-C treatment groups. No significant changes in the lightness and redness of the samples were observed in response to UV-C treatment, however, UV-C treatment led to a slight decrease in the yellowness of the samples. The initial taste, flavor, color, texture, and overall acceptance did not differ among control and UV-C treatments. The sensory score of the samples was the highest after 2 and 4 days of storage, while it decreased thereafter. In general, samples in the control and the 2.5 $kJ/m^2$ UV-C treatment groups showed higher sensory quality than those treated with UV-C at 5.0 $kJ/m^2$ or higher.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.6
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• pp.50-59
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• 2014

In this paper, Reinforced concrete (R/C) and R/C+steel plate concrete slab was carried out by SAP2000 software program in order to compare the stability of the multi-functional fishway, that is Bonggok fishway, built at Bonggok river recently in Gumi city, when the size of underground passage is $1m{\times}0.2m$, $1m{\times}0.4m$, $1m{\times}0.6m$ and the velocity is 0.8m/s, 1.2m/s, 1.6m/s respectively for the S2 (R/C+S/C). The analysis shows the maximum stress of S2 decreases less 26~50% than that of Bonggok, bending moment of sidewall decreases less 28~54%, maximum stress of side wall decreases less 17~31%, bending moment of upper slab decreases less 24~47%, maximum stress of upper slab decreases less 4~20%, and bending moment decreases less 10~27% than that of Bonggok. The complementation is required as much as the following percent; 27% and 25% for the maximum stress and bending moment of underground passage, 15% and 24% for the side wall maximum stress and bending moment, and 10% and 14% for the upper slab maximum stress and bending moment, respectively. This result shows that the S2 is greatly superior to that of the Bonggok fishway, and underground passage size of $1m{\times}0.4m$ is superior to that of $1m{\times}0.2m$ or $1m{\times}0.6m$, and R/C+S/C slab is superior to that of R/C slab. This result is expected to be the basic data for the construction and design of the multi-functional fishway.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.845-851
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• 2002

The synthesis of the intramolecular donor - stabilized silyl and germyl complexes of the type ($Cab^c.p) MMe_2X$ (2a:M=Si, X=Cl;2b;M= Ge, X=Cl;2e;M=Si,X=H) was achieved by the reaction of $LiCab^c,p$ (1) with $Me_2SiClX$ and $Me_2GeCl_2$ respectively. The intramolecular M←P interacion in 2a-2c is provided by $^1H$, $13^C.$, $31^P$ and $29^Si$ NMR spectroscopy. The salt elimination reactions of dichlorotetramethyldisilane and -digermane with 1 afforded the $bis(\sigma-carboranylphosphino)disilane$ and disgermane [$(Cab^C.P)MMe_2]_2(4a;M$ = Si;4b: M=Ge). The oxidative addition reaction of 4a-4b with $pd_2(dba)_3CHCl_3afforded$ the bis(silyl)-and bis(germyl)-palladium complexes. The chloro-bridged dipalladium complexes were obtained by the reaction of 2a-2b with $pd_2(dba)_3CHCl_3$ The crystal structures of 5a and 7b were determined by X-ray structural studies.

• Korean Journal of Microbiology
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• v.23 no.3
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• pp.177-183
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• 1985

Some properties of an extracellular cytosine deaminase produced from Arthrobacter sp.JH-13 were examined after 20-80% of ammonium sulfate fractionation. Among some substrates, this enzyme utilized cytosine and 5-fluorocytosine as a substrate. The optimum pH and temperature for the activity of this enzyme were found to be near 8.0 and $40^{\circ}C$, respectively. The ensyme was more stable in 0.2M of Tris-HCl buffer than 0.2M of potassium phosphate buffer. The enzyme was generally stable below $50^{\circ}C$, but inactivated completely at $70^{\circ}C$. 1mM of $Fe^{3+},\;K^+\;and\;Na^+$ increased the enzyme activity, but 0.01mM of $Co^{2+},\;Cu^{2+},\;Ni^{2+},\;Hg^{2+},\;Ag^{2+},\;Zn^{2+},\;Ba^{2+},\;and\;Mg^{2+}$ markedly inactivated the enzyme activity. 0.1mM of p-chloromercuribenzoate, trichloroacetic acid, and N-ethylmaleimide compleyely inhibited the enzyme activity, but 0.1mM of 2-mercaptoethanol slightly increased the enzyme activity.

• Journal of Ginseng Research
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• v.11 no.2
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• pp.136-144
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• 1987

Biosynthesis of saponins from acetate, mevalonate and squalene using root slices of panax ginseng C.A. Meyer was investigated. The sliced roots (2g) were incubated with the reaction mixture containing 20 M sodium acetate ($500\mu$Ci [U-$^{l4}C$]-acetate),10 mM mevalonate ($25\mu$Ci [2-$^{l4}C$]-mevalonate) or 10 mM swidme ($10\mu$Ci [4,8,12,13,17,21-$^3H$]-squalene) respectively at $30^{\circ}C$ for 72 hours. Biosynthesis of labelled ginseng saponine from [U-l4C]-acetate, [2-$^{l4}C$]-mevalonate and [4,8,12,13,17,21-$^3H$]-squalene was confirmed by autoradiography. Analysis of the products from [U-$^{l4}C$]-acetate by T.L.C. showed that the % radioactivities in panaxadiol, panaxatriol, squalene and mevalonate were found to be 2.1%, 2.7%, 2.6% and 0.2% respectively. Some of the sugars were also highly labelled. Analysis of the products from [2-$^{l4}C$]-mevalonate by T.L.C. showed that squalene was highly labelled and the products from [4,8,12,13,17,21-$^3H$]-squalene showed that panaxadiol, panaxatriol and sterol were highly labelled. From the above results, it was suggested that saponine might be synthesized from acetate via mevalonate-squalene route as expected in ginseng root.

• YAKHAK HOEJI
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• v.45 no.4
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• pp.413-418
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• 2001

To investigate action of ATP on ischemia-induced brain injury, we measured phospholipase $A_2$activity and nitric oxide (NO) production in C6 cells. ATP alone did not have any influence on phospholipase $A_2$activity but increased NO production. Glutamate (1 mM) significantly increased phospholipase $A_2$activity whereas did not increased NO production. ATP significantly inhibited phospholipase $A_2$activation induced by 0.1 $\mu$M A23187, 1 mM glutamate and 1 mM $H_2O$$_2$, but did not inhibited 1 $\mu$M PMA-induced phospholipase $A_2$activation. From the above results, it is suggested that the action of ATP in C6 cells has dual actions, such as the inhibition of agonist-induced phospholipase $A_2$activation and the increase of NO production.

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.13-16
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• 2003

Disposal possibility of raw food wastes which have various characters without any washing and composting process was tested directly using the earthworm, Eisenia andrei. The amount of feeding treatment a day by the earthworm was investigated according to input amount of 1.5 kg/m$^2$ or 3.0 kg/m$^2$ of fifteen food wastes with the different pH and EC. Earthworm disposed an average of 0.87 kg/m$^2$/day of food wastes at the constant temperature of 15$^{\circ}C$ and 1.01 kg/m$^2$/day at 2$0^{\circ}C$. The most disposal among fifteen food wastes was the food waste with pH 5.3 and EC 17.7 as 1.59 kg/m$^2$/day at 15$^{\circ}C$ and as 1.63 kg/m$^2$/day at 2$0^{\circ}C$. The least disposal was the food waste with pH 3.9 and EC 17.7 as 0.31 kg/m$^2$/day at 15$^{\circ}C$ and as 0.53 kg/m$^2$/day at 2$0^{\circ}C$. It took an average 4 days to dispose the amount of 3 kg raw food wastes at 15$^{\circ}C$ and 3.3 days at 2$0^{\circ}C$.

• Journal of Wetlands Research
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• v.14 no.2
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• pp.211-221
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• 2012

The ascidian Styela clava has been one of the favorite seafood in Korea. Suspended culture of Styela clava was initiated in 2001 and the annual production reached 15,084 M/T, but declined to 2,655 M/T in 2011. In order to solve this problem, it is necessary to estimate the material balance according to the farm-environment. Vertical particulate fluxes and release fluxes were estimated at 2 stations, an ascidian farm (AF) and a non-cultivated area (control) in Jindong Bay. An in-situ benthic chamber(BelcI) was used in summer and winter season. The sedimentation fluxes of organic carbon were 72 mmol C $m^{-2}\;d^{-1}$, 93 mmol C $m^{-2}\;d^{-1}$, 34 mmol C $m^{-2}\;d^{-1}$ in Jul. AF, Feb. AF, Feb. control. The organic carbon oxidation rates were 13 mmol C $m^{-2}\;d^{-1}$, 81 mmol C $m^{-2}\;d^{-1}$, 31 mmol C $m^{-2}\;d^{-1}$, in each. The release fluxes of nutrients followed the general pattern, well. Consequently, the ratio of the organic carbon burial fluxes were 20:4:1, in each. By the estimation of the carbon circulation, it could be a scientific basis to analyze the reason of production decline for cultivated organism.

• Fire Science and Engineering
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• v.22 no.5
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• pp.72-78
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• 2008

The mass loss rate and heat release rate of EPS sandwich panel cores were analysed using variable external irradiation level. The experimental materials were exposed to incident heat fluxes form 20 to 50 kW/$m^2$. For the measurement of mass loss rate and heat release rate, the size of specimen was $100mm{\times}100mm{\times}50mm$ and the samples were 3 different kinds. The combustion heat were carried out from the Oxygen bomb calorimeter and the mass loss rate and heat release rate were carried out from the Mass loss calorimeter according to ISO 5660-1. As the results of this study, the mass loss rate of Type A, B, and C were 2.7 g/$m^2s$, 2.8 g/$m^2s$, and 2.3 g/$m^2s$ and the heat release rate of Type A, B, and C were 58.23 kW/$m^2$, 47.19 kW/$m^2$, and 50.06 kW/$m^2$ respectively at the heat flux of 50 kW/$m^2$. In conclusion, when the heat release characteristics applied to a classification system of Canada, Type A and C can be classified grade C-3, and Type C can be classified grade C-2 from all data of this study.

• Analytical Science and Technology
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• v.14 no.6
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• pp.522-529
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• 2001

Carbon monoxide was generated when the saccharides which contained aldehyde group were added to alkali solution (NaOH solution) at $25^{\circ}C$ or $40^{\circ}C$. When the milk was added to 1.0 M NaOH solution at $25^{\circ}C$ and to 0.01 M NaOH solution at $40^{\circ}C$, carbon monoxide was generated. The carbon monoxide gas which was generated by 20 mL of 0.1 M lactose or 0.1 M xylose and 2 mL of 1.0 M NaOH solution at $50^{\circ}C$ for 2days was bubbled through 2 mL of fresh blood. The carboxyhemoglobin concentrations of both conditions were 31%. However, when the carbon monoxide gas which was generated by 30 mL of milk and 2 mL of 1.0 M NaOH at $50^{\circ}C$ for 2days or 3days was bubbled through 2 mL of fresh blood, the carboxyhemoglobin concentration was 32% or 42% respectively.