• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.769-772
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• 2008

The problem of disposing construction waste materials has become a national and social problem. Recycled powder generated in the process of making aggregate, and the recycled powder is land-filled in its entirety. Results of toxicity testing of recycled power show that it contains base-pair substituent mutagenicity. As recycled powder is disposed of as landfill, it can cause secondary contamination such as soil and underground water contamination. There has been very little research made on recycled powder. This study has examined the utilization of concrete mixture by using recycled powder in a mixture instead of cement and compared and analyzed the characteristics of dynamics and workability. This study has examined the application of recycled powder in concrete. Depending on the replacement rate and workability, test piece was manufactured using different mixing rate by CP, WCP, PCP. The CP was used to examine the physical property of concrete and characteristics its dynamics. The letters W of WCP and P of PCP are the initials of water and mixture. They were made using the standard mixing ratiosemphasizing the workability to determine the characteristic of dynamics of concrete based on the mixing ratio of recycled powder. With the increase in the replacement rate, CP had very little change in the strength. But with the decline of slump, the workability was not good. The result of manufacturing WCP and PCP using the standard mixing ratio showed that WCP had a drop in strength compared to the plain. PCP had almost the same value as the plain only when the replacement rate was 10%. When it was higher than that, a reduction in strength was observed.

• Tuberculosis and Respiratory Diseases
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• v.43 no.6
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• pp.903-915
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• 1996

Background: Combination chemotherapy is now considered to be the cornerstone of small cell lung cancer (SCLC). management but the optimal management of limited SCLC is not well defined. The role of thoracic radiotherapy (TRT) is less well established. Recent meta-analyses reports revealed that TRT combined with chemotherapy produce "good" local control and prolonged survival. But other reports that survival was not changed. The liming, dose, volume and fractionation for TRT with the combined chemotherapy of SCLC remains unsettled. In this study, we analyzed the effects according to the timing of thoracic radiotherapy in limited SCLC. Method: All fifty one patients received cytoxan, adriamycin and vincristine(CAV) alternating with etoposide and cisplatin(VPP) every 3 weeks for 6 cycles were randomized prospectively into two groups: concurrent and sequential. 27 patients received 4500cGy in 30 fractions(twice daily 150cGy fractional dose) over 3 weeks 10 the primary site concurrent with the first cycle of VPP(concurrent gorup). 24 patients received 4000 to 5000cGy over 5 or 6 weeks after completion of sixth cycles of chemotherapy(sequential group). Results: 1. Response rates and response duration : Response rates were not significantly different between two groups(p=0.13). But response duration was superior in the concurrent group(p=0.03). 2. Survival duration was nor different between two groups(p=0.33). 3. Local control rate was superior in the concurrent group(p=0.00). 4. Side effects and toxicities: Hematologic toxicities, especially leukopenia, infection and frequency of radiation esophagitis were higher in the concurrent group (p=0.00, 0.03, 0.03). Conclusion: The concurrent use of TRT with chemotherapy failed to improve the survival of limited stage SCLC patients compared with the sequential use of TRT but response duration and local control rate were superior in the concurrent group. Frequency of radiation esophagitis, life threatening hematologic toxicities and infection were more frequent in the concurrent group than sequential group. So, the selection of an optimal schedule of chemotherapy combined with TRT that would lead to a major increase in survival with minimal toxicity is remained to be validated in large scale study in the future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.2
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• pp.136-143
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• 1986

These studies were carried out to investigate effects of Lycii fructus extract on experimentally CC14-induced liver damage and alloxan-induced diabetes in rabbits and acute toxicity using mice. $LD_{50}(mg/kg)$ of Lycii fructus extract(L.F.E.) was 12.17g/kg by intraperitoneal administration in mice. L.F.E. showed more rapid recuperation compared to the control group in CC14-intoxicated rabbits and 800mg/kg was the most effective. Especially GPT activity and total bilirubin level showed an apparant decreasing effect within 6 days and 8 days, respectively in 800mg/kg. But any differences were not observed in alkaline phosphatase and total cholesterol between sample and control group. Large amount administered group exhibited more excellent hypoglycemic effect in alloxan-induced diabetes of rabbits, that is, it was significant to the control group after 4 days and adjacent to the normal level on 12th day. And GPT activity was gradually decreased and showed clear decreasing effect after 6 days. It is suggested that L.F.E. can be administered not only as therapeutic agents (such as liver tonics or antidiabetetics) but also a natural food to shorten the recovery time of hepatic function in liver diseases and decrease the abnormally elevated blood glucose such as Diabetes Mellitus.

• Korean Chemical Engineering Research
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• v.53 no.3
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• pp.289-294
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• 2015

In this research, water and ethanol extract of Momordica charantia shells, fruits and seeds were tested to see possibility as natural functional cosmetic agent. Water and ethanol extract showed 69.45 mg/g and 70.87 mg/g polyphenol concentration, respectively. Momordica charantia water and ethanol extracts did not indicate cell toxicity up to $1,000{\mu}g/ml$ concentration in MTT assay. Tyrosinase inhibition effects of water and ethanol extract were lower than arbutin, however, ethanol extract showed better DOPA oxidation inhibition effect than arbutin. Elastase inhibition effects of ethanol extract displayed similar efficacy with adenosine at higher concentrations. Solution formulations (5% extract) were stable for 28 days in both extracts, however, lotion formulation (1% extract) showed considerable variation in viscosity whereas ethanol extraction indicated relative stability. In conclusion, water and ethanol extract of Momordica charantia shells, fruits and seeds indicated strong possibility for whitening and antiwrinkle functional cosmetic ingredient.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.217-222
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• 2012

The synthesis of dimethyl carbonate(DMC) is a promising reaction for the use of naturally abundant carbon dioxide. DMC has gained considerable interest owing to its versatile chemical reactivity and unique properties such as high oxygen content, low toxicity, and excellent biodegradability. In this study, the synthesis of DMC through the transesterification of ethylene carbonate(EC) with methanol was investigated by using ionic liquid and metal oxide catalysts. The screening test of different catalysts revealed that choline hydroxide ([Choline][OH]) and 1-n-butyl-3-methyl imidazolium hydroxide([BMIm][OH]) had better catalytic performance than metal salts catalysts such as MgO, ZnO and CaO. The effects of reaction parameters such as reaction temperature, MeOH/EC mole ratio, and carbon dioxide pressure on the reactivity of [Choline][OH] catalyst were discussed. High temperature and high MeOH/EC mole ratio were favorable for high conversion of EC. However, the yield of DMC showed a maximum when carbon dioxide pressure was 1.34 MPa, and then it decreased for higher carbon dioxide pressure. Zinc chloride($ZnCl_2$) was used as co-catalyst with the ionic liquid catalyst. The mixed catalyst showed a synergy effect on the EC conversion and DMC yield probably due to the acid-base properties of the catalysts.

• Resources Recycling
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• v.24 no.6
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• pp.69-77
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• 2015

Heap bioleaching for detoxification of mine tailings is a promising technology; however, long-term studies that aim to understand the potential of this process are scarce. Therefore, this study assesses the feasibility of column bioleaching as an alternative technology for treatment of mine tailings with high concentrations of arsenic during a long-term experiment (436 days). To accomplish this objective, we designed a 350-mm plastic column that was packed with 750 g of mine tailings and inoculated with an acidophilic bacterial culture composed of A. thiooxidans and A. ferrooxidans. Redox potential, pH, ferric ion generation, and arsenic concentration of the off-solution were continuously monitored to determine the efficiency of the technology. After 436 days, we obtained up to 70% arsenic removal. However, several drops in removal rates were observed during the process; this was attributed to the harmful effect of arsenic on the bacteria consortium. We expect that this article will serve as a technical note for further studies on heap bioleaching of mine tailings.

• KSBB Journal
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• v.30 no.4
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• pp.148-154
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• 2015

Onion (Allium cepa) is one of the flavonoids-rich materials in human diet and onion peel, which is the onion by-products, contains over 20 times more quercetin than the flesh. In this study, to examine the anti-inflammatory effects of onion peel hot water extract (OPHWE), the cell viability, nitric oxide (NO), pro-inflammatory cytokines, such as interluekin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and IL-$1{\beta}$, were measured using the murine macrophage cell line RAW 264.7 cells. The Balb/c mice were used for an in vivo acute toxicity test and ICR mice were used for measurement of inhibition effects of croton oil-induced mouse ear edema. As a result, NO levels decreased in a dose-dependent manner. The production of IL-6, TNF-${\alpha}$, and IL-$1{\beta}$ was suppressed by 38%, 41%, and 34% respectively, compared with that of the LPS only group, without any cytotoxicity. The edema formation in the ICR mouse ear was also reduced compared to that in control. Moreover, there were no mortalities occurred in mice administered 5,000 mg/kg body weight of OPHWE. These results suggest that OPHWE has considerable anti-inflammatory activities and can be regarded as a potent candidate material to treat inflammatory diseases.

• Journal of Environmental Health Sciences
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• v.40 no.3
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• pp.234-244
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• 2014

Objectives: This study was carried out in order to analyze the composition of the leaves and stems of Abeliophyllum distichum Nakai, with the aim of obtaining basic data for utilizing the plant as a food ingredient, as well as for processing. Methods: Leaves and stems from Abeliophyllum distichum Nakai were harvested at Cheongcheon-myeon, Geosan-gun, Chungcheongbuk-do, and were subsequently freeze-dried and ground to a fine powder for chemical component analysis and safety evaluation. Results: The moisture contents of Abeliophyllum distichum Nakai leaves and stems were respectively 65.07% and 40.97%, and the crude ash contents were 1.32% and 0.91%. In addition, the crude protein contents were 11.97% and 3.77%, and the crude fat contents were 2.52% and 0.36%, respectively. The fructose and glucose contents were 32.13 mg/g and 56.17 mg/g for leaves, and 11.38 mg/g and 10.59 mg/g for stems. The major fatty acids of the leaves were palmitic acid (31.79%) and stearic acid (14.79%), and those for stems were linolenic acid (32.78%) and palmitic acid (26.75%). The ascorbic acid contents of leaves and stems were 1.32 mg/g and 0.30 mg/g respectively. The calcium content was found to be the highest among the minerals tested, both in the leaves and stems, with the levels being 166.17 mg/100 g for leaves and 592.34 mg/100 g for stems. The content of organic acid was greater in leaves than in stems, with that of malic acid accounting for more than 75% of total organic acids for both samples. The total phenolic compounds and flavonoid contents of Abeliophyllum distichum Nakai were 50.64 mg/g and 13.53 mg/g in leaves and 96.47 mg/g and 18.53 mg/g in stems, respectively. No changes were shown in the number of micronucleated polychromatic erythrocytes (MNPCE) among 2,000 polychromatic erythrocytes compared to the negative control. Abeliophyllum distichum Nakai was administered orally to rats in order to investigate acute toxicity. The $LD_{50}$ values in rats were above 2,000 mg/kg. Conclusion: These results indicate that the leaves and stems of Abeliophyllum distichum Nakai can be used as natural ingredients in the development of nutritional and functional materials.

• Clean Technology
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• v.6 no.2
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• pp.113-119
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• 2000

Due to the toxicity of dioxin in the incinerator flue gas, it becomes a severe social problem. Activated carbon adsorption process is one of the methods for removing dioxin in the flue gas and was investigated its performance for removing hazardous organic compounds. Since dioxin is very hazardous material, 1,2-dichlorobenzene(o-DCB), one of the precursor material of dioxin, was used as adsorbate. The effects of air flow rate, pressure drop in the bag filter, operation temperature of bag filter, and kinds of adsorbents on the removal of o-DCB were measured and analysed. Experimental results showed that the operating temperature was recommended within the range of $140{\sim}170^{\circ}C$ considering the operating condition of incinerator. Also it was necessary to maintain the pressure drop of bag filter $120mmH_2O$ for enhancing the adsorption at the surface layer of activated carbon formed on the bag filter. The use of mixture of same amount of activated carbon and diatomite showed more than 90% removal of o-DCB and also reduced the consumption of activated carbon.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.403-412
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• 2017

To investigate the control effect of insect pests by natural enemies, sticky traps were used in commercial tomato greenhouses in Chun-cheon and the experiment fields of Gangwon-do Agricultural Research and Extension Services, Republic of Korea using semi-forcing culture (February to June). We selected low toxicity pesticides, environment-friendly agricultural materials (EFAM), and natural enemies of the study species, combinations of which have been previously used in farms to control insect pests. In this study, Trialeurodes vaporariorum and thrips, which are major agricultural insect pests, were studied in experimental greenhouses. The adult T. vaporariorum population was observed in mid-April and the population of thrips showed occurrences in early April. Regarding seasonal fluctuation, T. vaporariorum peaked in mid-May and thrips peaked after June. one insecticide, spiromesifen suspension concentrate (SC); one fungicide, cyazofamid SC; and two EFAMs containing neem tree extract were shown to be slightly toxic to Encarsia formosa and Orius laevigatus. The results of this study could be used to develop management models using natural enemies of control the insect pests; T. vaporariorum and thrips in semi-forcing culture of tomato.