• Journal of Life Science
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• v.19 no.5
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• pp.652-658
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• 2009

The comparative activities of aqueous, ethanol, and methanol extracts from Aralia elata shoot (AES) and leaf (AEL) were tested by in vitro experimental models of linoleic acid peroxidation by thiocyanate and thiobarbituric acid (TBA) methods and scavenging activities of free radicals by DPPH (${\alpha}$,${\alpha}$'-diphenyl-${\beta}$-picrylhydrazyl). In addition, bio-active materials (phenolic compounds and minerals) were also measured. The extract yield of each solvent extracted from AES and AEL was 3.08% and 3.13% in aqueous, 0.58% and 0.66% in ethanol, and 0.81% and 1.73% in methanol, respectively. The highest extract yield was found in the aqueous extract from AEL. Major mineral contents (mg%) of AES and AEL were 575.7 and 759.3 in Ca, 353.5 and 330.0 in K, and 31.3 and 31.0 in Mg, respectively. The highest free radical scavenging activity was found in the aqueous extract by 28.69% at 0.1% additional level from AES and in the methanol extract by 92.36% at 0.1% additional level from AEL. Free radical scavenging activity was stronger in AEL than in AES. In antioxidative activities determined by thiocyanate and TBA methods against lipid peroxidation using linoleic acid, ethanol extracts from AEL showed the highest antioxidative activity at all treatment concentrations. These results may provide the basic data to understand the biological activities of bio-active materials derived from AES and AEL.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.163-169
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• 2012

We have conducted three experiments to develop a fertilizer-dissolving apparatus used in fertigation or hydroponics cultivation in order to decrease the fertilizer dissolving time and labor input via automation. All of the experiments were conducted twice. In the first experiment, four selected treatments were tested to dissolve fertilizers rapidly. The first treatment was to dissolve fertilizer by spraying water with a submerged water pump, placed in the nutrient solution tank. The water was sprayed onto fertilizer, which is dissolved and filtered through the hemp cloth mounted on the upper part of the nutrient solution tank (Spray). The second treatment was to install a propeller on the bottom of the nutrient solution tank (Propeller). The third treatment was to produce a water stream with a submerged water pump, located at the bottom of the tank (Submerged). Finally, the fourth treatment was to produce an air stream through air pipes with an air compressor located at the bottom of the tank (Airflow). The Spray treatment was found to take the shortest time to dissolve fertilizer, yet it was inconvenient to implement and manage after installation. The Airflow treatment was thought to be the best method in terms of the time to dissolve, labor input, and automation. In the second experiment, Airflow treatment was investigated in more detail. In order to determine the optimal number of air pipe arms and their specification, different versions of 6- and 8-arm air pipe systems were evaluated. The apparatus with 6 arms (Arm-6) that was made of light density polyethylene was determined to be the best system, evaluated on its time to dissolve fertilizer, easiness to use regardless of the lid size of the tank, and easiness to produce and install. In the third experiment, the Submerged and Arm-6 treatments were compared for their dissolving time and economics. Arm-6 treatment decreased the dissolving time by 8 times and proved to be very economic. In addition, dissolving characteristics were investigated for $KNO_3$, $Ca(NO_3)_2{\cdot}4H_2O$, and Fe-EDTA.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.261-266
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• 2012

This study was carried out in order to investigate the effect of MA packaging material on quality and shelf life of ferulae mushroom (Pleurotus ferulae) at 1, 8, and $24^{\circ}C$ storage temperatures. We found that the fresh weight loss was less than 1.5% in all temperatures (1, 8, and $24^{\circ}C$) and non-perforated breathable films (1,300 cc, 3,000 cc, 5,000 cc, 7,000 cc, 10,000 cc, 15,000 cc, 20,000 cc, and $40,000cc/m^2{\cdot}day{\cdot}atm$ oxygen transmission rate) treatments. The proper MA packaging material of ferulae mushroom was 1,300 cc and 3,000 cc films at $1^{\circ}C$ storage. Because 1,300 cc and 3,000 cc films showed proper level, 15% carbon dioxide and 5% oxygen concentration for MA storage, although the shelf life was higher in 1,300 cc (42 days) than 3,000 cc (38 days), and the ethylene concentration as well as off-order showed lower in 3,000 cc than 1,300 cc film. The 3,000 cc film was the most suitable for ferulae mushroom storage at $8^{\circ}C$, because atmosphere composition in package was not statistically significantly different among the film treatments. In addition, 3,000 cc film showed the second low ethylene concentration and the longest shelf-life of 19 days. The ferulae mushroom stored at $25^{\circ}C$ showed a vigorous respiration and resulted in an extreme CA condition in package at $5^{th}$ day after storage, and showed the highest visual quality in 1,300 cc film. As the shelf life of ferulae mushroom at $1^{\circ}C$ and $8^{\circ}C$ storage were 8 times and 4 times longer than at $25^{\circ}C$ storage respectively, so the ferulae mushroom should be stored and distributed in cold chain system.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2A
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• pp.129-136
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• 2011

Recently studies on functional concrete with a photocatalytic material such as $TiO_2$ have actively been carried out in order to remove air pollutants. The absorbtion of $TiO_2$ from those studies is applied by it being directly mixed into concrete or by suspension coated on the surface. When it comes to the effectiveness, the former process is less than that of the latter compared with the $TiO_2$ use. As a result, the direct coating of $TiO_2$ on materials' surface is more used for effectiveness. The Surface spread of it needs to have a more than $400^{\circ}C$ heat treat done to stimulate the activation and adhesion of photocatalysis. Heat treat consequently leads hydration products in concrete to be dehydrated and shrunk and is the cause of cracking. The study produces $TiO_2$ used Sol-gel method which enables it to be coated with a low temperature treat, applies it to pearlite using Lightweight Aggregate Concrete fixed with a low temperature treat and evaluates the spread performance of it. In addition to this, the size of pearlite is divided into two types: One is 2.5 mm to 5.0 mm and the other is more than 5.0 mm for the benefit of finding out the removal characteristics of $CH_3CHO$ whether they are affected by pearlite size, mixing method and ratio with $TiO_2$ and elapsed time. The result of this experiment shows that although $TiO_2$ produced by Sol-gel method is treated with 120 temperature, it maintains a high spread rate on the XRF(X ray Florescence) quantitative analysis which ranks $TiO_2$ 38 percent, $SiO_2$ 29 percent and CaO 18 percent. In the size of perlite from 2.5 mm to 5.0 mm, the removal characteristic of $CH_3CHO$ from a low temperature heated Lightweight concrete appears 20 percent higher when $TiO_2$ with Sol-gel method is spreaded on the 7 percent of surface. In other words, the removal rate is 94 percent compared with the 72 percent where $TiO_2$ is mixed in 10 percent surface. In more than 5.0 mm sized perlite, the removal rate of $CH_3CHO$, when $TiO_2$ is mixed with 10 percent, is 69 percent, which is similar with that of the previous case. It suggests that the size of pearlite has little effects on the removal rate of $CH_3CHO$. In terms of Elapsed time, the removal characteristic seems apparent at the early stage, where the average removal rate for the first 10 hours takes up 84 percent compared with that of 20 hours.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.131-140
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• 2000

Compostable household wastes(mainly food residues) were composted in a small bin for 30 days, in which compostable household wastes were fed every day and mixed thoroughly under aerobic conditions. Three small bins were employed. In the first bin only recycled compost was composted, in the second, compostable household wastes with recycled compost, and in the third compostable household wastes with recycled compost and vermiculture. The correct decomposition rate of each composting material was calculated during composting. Total reduced rate of the weight after 30 days was 57.32% when composting the compostable household wastes with recycled compost, and 64.71% when composting them with recycled compost and vermiculite. In the case of composting the compostable household wastes with the recycled compost, the total weight reduction rate for a day was 6.81% and the total decomposition rate 6.81%. Their difference was not great. But in the case calculated with only compostable household wastes the total weight reduction rate was 56.34% and the decomposition 6.79%. When compostable household wastes were composted with the recycled compost and vermiculite, the total weight reduction rate was 64.99% and the decomposition rate 1.48%, but the total weight reduction 4.36% and the decomposition rate 35.46% when calculated with only compostable household wastes. MgO, $K_2O$ and Cr concentrations in the composting mixture during the early composting time were higher when composted with vermiculite than without it, but organic matter, CaO, NaCl, and $P_2O_5$ concentrations were contrarily diluted because of their lower concentration of vermiculite when compostable household wastes were composted with vermiculite.

• Economic and Environmental Geology
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• v.52 no.6
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• pp.627-635
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• 2019

Cement-asbestos slate is the main asbestos containing material. It is a product made by combining 10~20% of asbestos and cement components. Man- and weathering-induced degradation of the cement-asbestos slates makes them a source of dispersion of asbestos fibres and represents a priority cause of concern. When the asbestos enters the human body, it causes cellular damage or deformation, and is not discharged well in vitro, and has been proven to cause diseases such as lung cancer, asbestos, malignant mesothelioma and pleural thickening. The International Agency for Research on Cancer (IARC) has designated asbestos as a group 1 carcinogen. Currently, most of these slats are disposed in a designated landfill, but the landfill capacity is approaching its limit, and there is a potential risk of exposure to the external environment even if it is land-filled. Therefore, this study aimed to exam the possibility of detoxification of asbestos-containing slate by using exothermic reaction and heat treatment. Cement-asbestos slate from the asbestos removal site was used for this experiment. Exothermic catalysts such as calcium chloride(CaCl₂), magnesium chloride(MgCl₂), sodium hydroxide(NaOH), sodium silicate(Na₂SiO₃), kaolin[Al₂Si₂O₅(OH)₄)], and talc[Mg₃Si₄O₁₀(OH)₂] were used. Six catalysts were applied to the cement-asbestos slate, respectively and then analyzed using TG-DTA. Based on the TG-DTA results, the heat treatment temperature for cement-asbestos slate transformation was determined at 750℃. XRD, SEM-EDS and TEM-EDS analyses were performed on the samples after the six catalysts applied to the slate and heat-treated at 750℃ for 2 hours. It was confirmed that chrysotile[Mg₃Si₂O₅(OH₅)] in the cement-asbestos slate was transformed into forsterite (Mg₂SiO₄) by catalysts and heat treatment. In addition, the change in the shape of minerals was observed by applying a physical force to the slate and the heat treated slate after coating catalysts. As a result, the chrysotile in the cement-asbestos slate maintained fibrous form, but the cement-asbestos slate after heat treatment of applying catalyst was broken into non-fibrous form. Therefore, this study shows the possibility to safely verify the complete transformation of asbestos minerals in this catalyst- and temperature-induced process.

• The Korean Journal of Pharmacology
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• v.25 no.1
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• pp.53-58
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• 1989

For several years, we investigated the pharmacological action of several substances isolated from Buxus microphylla var koreana Nakai, which had been used as folk remedies of malaria and venereal disease. Cyclobuxine $D(C_{25}H_{42}ON_2)$, a steroidal alkaloid, exerted an antiinflammatory action, hypotensive and bradycardic effects in rats. In the present study, we isolated alkaloid from the acetone-insoluble fraction of the strong bases of this plants. This alkaloid $(C_{25}H_{38}ON_2)$ was identified as a steroidal alkaloid contained a cyclopropane ring by physical and chemical methods. It is a derivative of cyclobuxine D and named cyclobuxine E. We examined the effect of cyclobuxine E on the contractile response induced by acetylcholine and two distinct types of potassium-activated calcium channels in an intestinal smooth muscle of the rat. Cyclobuxine E inhibited significantly the Ach-induced contraction. The isolated longitudinal muscle from the rat duodenum was immersed calcium-depleted potassium depolarizing solution. Ten minutes after, 1.8 mM $CaCl_2$ was added to muscle bath and elicited a biphasic increase in muscle tension. Cyclobuxine E produced an appreciable inhibition of both components of the mechanical response. In addition, Cyclobuxine E introduced at a point when the tonic response had reached its maximum level, caused the muscle to exhibit a rapid loss of tension. Based on these experimental results, we proposed the possibility that the inhibitory action of cyclobuxine E on the isolated rat duodenum may be due to inhibiting the transmembrane fluxes of calcium ion in potassium-activated calcium channels.

• Journal of Korean Society of Forest Science
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• v.81 no.3
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• pp.273-279
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• 1992

Protoplasts isolated from leaf mesophyll tissues of Populus koreana ${\times}$ P. nigra var. italica were fused with those of P. euramericana cv. Guardi. Well expended healthy leaves of 5 to 7 week-old-plantlet grown in vitro were used as source materials. Leaves from P. koreana ${\times}$ P. nigra var. italica and P. euramericana cv. Guardi were digested in enzyme solution I (2.0% Cellulase, 1.2% Hemicellulase, 0.4% Macrozyme, 2.0% Driselase, 0.05% Pectolyase ; w/v) and enzyme solution II (1.0% Cellulase, 1.2% Hemicellulase, 0.4% Macrozyme, 2.0% Driselase, 0.05% Pectolyase ; w/v), respectively, The highest frequency of fusion among the protoplasts originated from the two source materials was approximately 21% using 40% PEG or 15% dextran. In addition, fusion frequency was enhanced by incorporating 30mM of $Ca^{2+}$ in eluting solution at pH 10.5. Dividing cells and/or mint-calli were obtained by culturing the fusion products in a liquid 8p-KM medium supplemented with 0.6M sucrose, $0.45{\mu}M$ 2, 4-D, and $0.5{\mu}M$ BA. Shoots were regenerated from the fusion product-derived calli after culture on MS medium containing $5.0{\mu}M$ zeatin. To verify the putative hybrid or cybrid, SDS-PAGE was carried out. From the 24 regenerants, just two plants showed intermediate protein band patterns compared with those of the original source plants.

• Analytical Science and Technology
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• v.9 no.3
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• pp.279-291
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• 1996

The new chelating resins, XAD-2, 4, 16-TAC and XAD-2, 4, 16-TAO were synthesized by Amberlite XAD-2, XAD-4, and XAD-16 macroreticular resins with 2-(2-thiazolylazo)-p-cresol(TAC) and 4-(2-thiazolylazo)orcinol(TAO) as functional groups and were characterized by elemental analysis and FT-IR spectrometry. It was found that the content of functional group in chelating resin was 0.60mmol/g in XAD-16-TAC and 0.68mmol/g in XAD-16-TAO respectively. The chelating resins were stable in acidic and alkaline solution and can be reused over 10 times. The sorption behavior of some metalions to two chelating resins was investigated by batch method, which included batch equilibrium, effect of pH, coexisting ions and masking agent. For the optimum condition of sorption, the time required for equilibrium was about 1 hour and optimum pH was 5. In the presence of anions such as ${SO_4}^{2-}$ and $CH_3COO^-$, the sorption of U(VI) ion was slightly reduced but other anions such as $Cl^-$ and $NO{_3}^-$ revealed no interference effect. Also, sorption capacity of U(VI) ion was decreased by addition of $CO{_3}^{2-}$ ion because of complex formation of $[UO_2(CO_3)_3]^{4-}$, but alkali metals and alkali earth metals including Na(I), K(I), Mg(II), and Ca(II) were not affected for the sorption extent. Masking agent, NTA showed better separation efficiency of U(VI) ion from coexisting metal ions such as Th(IV), Zr(IV), Hf(IV), Cu(II), Cd(II), Pb(II), Ni(II), Zn(II) and Mn(II) than EDTA, CDTA.

• Journal of environmental and Sanitary engineering
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• v.3 no.2 s.5
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• pp.61-78
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• 1988

This study was carried out to clarify the effect of dietary calcium, casein and suet on intestinal absorption of cadmium in mice. It was performed for 30 days, from April 11, to May 10, 1988. Ninety mice were devided into 4 experimental groups and control group with 6 mice each dietary group, and measured survival ratio, body weight and weight ratio of organ to body. The contents of cadmium in liver, kidney, spleen, muscle and skin with hair, and feces were analyzed by atomic absorption spectrophotometer after sacrifice by anesthesia. The ratio of survival after 30 day breeding was $100\%$ in control group, but $66.7\%$ in group IV(basal diet + Cd + Ca) with $100{\mu}g$ one dose and with 50ppm cadmium containing fluid free-intake, and group V (basal diet + Cd + suet) with free-intake of 50ppm containing cadmium fluid. The ratio of body weight gains in cases of single dose $100{\mu}g$ of cadmium was highest as $42.3\%$ in group IV and lowest as $26.0\%$ in group V, in cases of free-intake of 50ppm containing cadmium fluid was highest as $24.0\%$ in group IV and lowest as $11.6\%$ in group II (basal diet + Cd). The body weight, in the case of single dose of $100{\mu}g$ of cadmium showed no increase untill 5th day from acute poisoning. While in case of free-intake of 50ppm containing cadmium, it showed very slight increase through all breeding period. The weight ratio of organ to body were lowest in liver of group II in both occasions. The most of cadmium administered was excreated in feces within 2 days after single dose $100{\mu}g$ cadmium. The contents of cadmium in all tissues were significantly high in each group comparing to control group as liver, kidney, spleen and muscle of group II which showed the highest level in both occasions of $100{\mu}g$ one dose and free-intake of 50ppm containing cadmium fluid, and higher in group II of the occasion with $100{\mu}g$ single dose, and in group V of the occasion of 50ppm containing cadmium fluid free-inatke for skin with hair. And the content of cadmium in tissues is generally higher in the occasion of 50ppm containing cadmium free-intake than $100{\mu}g$ single dose. From the above results I conclude that the addition of casein, calcium and suet in cadmium containing diet is effective to inhibtion of intestinal absorption of cadmium by particularly, calcium.