• Korean Chemical Engineering Research
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• v.55 no.3
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• pp.385-394
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• 2017

In this study, reaction mechanism and curing characteristics of adhesives formulated with NaOH- and $H_2SO_4$-hydrolyzed chicken feather (CF) and formaldehyde-based crosslinkers were investigated by FT-IR and DSC. In addition, adhesive properties and formaldehyde emission of medium-density fiberboards (MDF) applied with the adhesives were measured. CF-based adhesives having a solid content of 40% and over were very viscous at $25^{\circ}C$, but the viscosity reduced to $300{\sim}660m{\cdot}Pa{\cdot}s$ at $50^{\circ}C$. Consequently, the adhesives could be used as a sprayable resin. Through the FT-IR spectra of liquid and cured CF-based adhesives, addition reaction of methylol group and condensation reaction between the functional groups with the use of formaldehyde-based crosslinkers were identified. From the analysis of DSC, it was elucidated for CF-based adhesives to require a higher pressing temperature or longer pressing time comparing to commercial urea-formaldehyde (C-UF) resin. MDF bonded with CF-based adhesives, which was formulated with 5% NaOH-hydrolyzed CF (CF-AK-5%) and PF of formaldehyde to phenol mole ratio of 2.5 (PF-2.5), and pressed for 8 min had higher MOR and IB than those with other CF-based adhesives. MOR and IB of MDF bonded with the CF-based adhesives regardless of formulation type and pressing time were higher than those with C-UF resin. When the values compared with the minimum requirements of KS standard, IB exceeded the KS standard in all formulations and pressing time, but MOR of only MDF bonded with CF-AK-5% and PF-2.5 and pressed for 8 min satisfied the KS standard. What was worse, 24-TS of MDF bonded with all CF-based adhesives did not satisfied the KS standard. However, MOR and 24-TS can be improved by increasing the target density of MDF or the amount of wax emulsion, which is added to improve the water resistance of MDF. Importantly, the use of CF-based adhesives decreased greatly the formaldehyde emission. Based on the results, we reached the conclusion that CF-based adhesives formulated under proper conditions had a potential as a sprayable resin for the production of wood panels.

• Journal of the Korea Concrete Institute
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• v.25 no.3
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• pp.321-329
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• 2013

Recently, the medium-low level radioactive waste from nuclear power plant must be transported from temporary storage to the final repository. Medium-low level radioactive waste, which is composed mainly of the liquid ion exchange resin, has been consolidated with cementitious material in the plastic or iron container. Since cementitious material is brittle, it would generate cracks by impact load during transportation, signifying leakage of radioactive ray. In order to design the safety transporting equipment, there is a need to check the compressive strength of the current waste. However, because it is impossible to measure strength by direct method due to leakage of radioactive ray, we will estimate the strength indirectly by the dynamic modulus of elasticity. Therefore, it must be identified the relationship between of strength and dynamic modulus of elasticity. According to the waste acceptance criteria, the compressive strength of cement based solid is defined as more than 3.44 MPa (500 psi). Compressive strength of the present solid is likely to be significantly higher than this baseline because of continuous hydration of cement during long period. On this background, we have tried to produce the specimens of the 28 day's compressive strength of 3 to 30 MPa having the same material composition as the solid product for the medium-low level radioactive waste, and analyze the relationship between the strength and the dynamic modulus of elasticity. By controling the addition rates of AE agent, we made the mixture containing the ion exchange resin and showing the target compressive strength (3~30 MPa). The dynamic modulus of elasticity of this mixtures is 4.1~10.2 GPa, about 20 GPa lower in the equivalent compressive strength level than that of ordinary concrete, and increasing the discrepancy according to increase strength. The compressive strength and the dynamic modulus of elasticity show the liner relationship.

• Korean journal of applied entomology
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• v.57 no.3
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• pp.209-220
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• 2018

Mating disruption (MD) has been widely used to effectively control Grapholita molesta in apple orchards. A simultaneous mating disruption (SMD) techniques have been developed to control both G. molesta and G. dimorpha. This study was performed to determine the practical parameters to apply the SMD technique to field conditions. To determine the application amount of SMD lures, a dispenser containing 10 mg pheromone was placed at different numbers of trees in an orchard. Application at every other tree (= one dispenser per two trees) was relatively safe to expect effective MD efficiency in both wax and polyethylene (PE) formulations. One time application at the end of March was enough to maintain a year round MD efficacy against both species. A fence treatment using food trap was applied to prevent any immigratory mated females from nearby untreated regions. To enhance the food trap by adding host-derived secondary compounds, terpinyl acetate (TA) was screened to be effective to attract females of Grapholita molesta among six compounds contained in apple fruit extracts. Among different TA concentrations, 0.05% TA treatment was the most effective to attract the adults. A mixture of TA and sugar was effective to attract and kill females and called FAKT (female attract-to-kill techniques). FAKT was treated at approximately 6 m interval at the edge of the apple orchards. The females trapped by the FAKT included mated females possessing vitellogenic oocytes. SMD supplemented with FAKT maintained the high MD efficacy and significantly suppressed leaf damage induced by the two insect pests compared to control or single SMD treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.10
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• pp.1484-1490
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• 2014

In the present study, we examined the effects of a mixture of three strains, Lactobacillus plantarum CECT 7527, 7528, and 7529 (L. plantarum mixture), on body weight and lipid metabolism in Sprague-Dawley rats fed a high-fat diet. Rats were fed a high-fat diet and subjected to oral gavage with vehicle or the L. plantarum mixture ($0.6{\times}10^9$, $1.2{\times}10^9$, $2.4{\times}10^9$ colony-forming units (CFU)/day/rat, respectively) for 8 weeks. In rats fed a high-fat diet, oral administration of $2.4{\times}10^9CFU/day$ of the L. plantarum mixture significantly reduced body weight gain as well as weights of liver and epididymal fat. Leptin levels in sera were significantly reduced by oral administration of $2.4{\times}10^9CFU/day$ of the L. plantarum mixture. The L. plantarum mixture ($1.2{\times}10^9$ or $2.4{\times}10^9CFU/day$) also reduced the concentrations of total cholesterol and LDL-cholesterol in sera when it administered orally. Further, the L. plantarum mixture significantly reduced the atherogenic index and cardiac risk factor. In addition, oral administration of $2.4{\times}10^9CFU/day$ of the L. plantarum mixture markedly reduced levels of total lipids, triglycerides, and total cholesterol in the liver. The results of this study indicate that the L. plantarum mixture may exhibit anti-obesity and cholesterol-lowering effects, which suggest that the L. plantarum mixture has the potential to be a probiotic in the management of obesity and hypercholesterolemia.

• Research in Plant Disease
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• v.16 no.1
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• pp.27-34
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• 2010

This study was performed to develop a formulation using an antagonistic bacterium Bacillus amyloliquefaciens A-2 to control tomato leaf mold caused by Fulvia fulva. B. amyloliquefaciens A-2 was grown in a medium with rice oil and mixed with various carrier and additives. One of the formulations, A2-MP, showed the best disease control value among the tested formulations. The disease control value of A2-MP at 100-fold and 500-fold diluted treatment was not significantly different from that of chemical fungicide triflumizole in a growth chamber. Although disease control effect was decreased by serial diluted treatment of the prepared A2-MP, 1,000-fold diluted treatment of A2-MP still showed high disease control value of 72.0%. For the green house experiments, the disease control values of A2-MP was indicated as 79.4% which is similar to that of chemical fungicide, triflumizole showing 79.6%. When the disease control activity of the formulation A2-MP was compared in tomato production conditions, disease control values of 100-fold diluted A2-MP and 3,000 fold diluted triflumizole exhibited 60%, 81.6%, respectively. The disease control efficiency by A-2MP was 73% of the disease control value of chemical fungicide. The formulation A-2MP maintained the stable bacterial viability and disease control activity when stored at $4^{\circ}C$. This result suggested that A-2MP develped from B. amyloliquefaciens A-2 could be used to control tomato leaf mold.

• 한국해양학회지
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• v.30 no.3
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• pp.184-196
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• 1995

The line-SW is located in the mouth of Gomso Bay (20 Km long and 5-8 Km wide),west coast of Korea. This area is composed of sand flat, mud flat, sand shoal and chenier, The difference of physical, geological and geomorphic conditions in subenvironments of the bay may control and produce distingtive foraminiferal populations and assemblages. This study investigates whether five a priori subenvironments (five local zonations) in Gomso-Bay tidal flat can be distinguished from each other on the basis of total (living plus dead) foraminiferal assemblages. Seventy-four species (67 benthic; 7 planktonic) were recorded in total assemblages of surface sediments from 10 stations. Ammonia beccarii tepida, Discorbis candeiana, Elphidium etigoense and Eponides nipponicus were most dominant species in living and total assemblages. The relative abundance (%) of living population was high at upper flat and decreased from upper to lower flat. The low percentages of living populations in middle to lower flat are probably influenced by the decreasing reproduction of foraminifera caused by high energy condition and addition of dead species from offshore. The occurence of planktonic foraminifera in middle to lower flat (5.3∼6.6%) indicates introduction of planktonic foraminifera from offshore by storm and/or tidal current. The relatively high numbers of species in lower middle to lower flat are probably caused by a mixing of faunas from these areas and offshore. The high numbers of total individuals per 50 ml of sediment in upper flat indicate that this area is a relatively stable environment where waves and currents are protected by the chenier. Five biofacies of the total foraminiferal assemblages were established on the basis of dominant species (those representing more than 20% of the total assemblages in any station) in the five a priori subenvironments recognized along the Line-SW transect in Gomso-Bay tidal flat. Five biofacies are potentially useful in paleoenvironmental interpretation in late Quaternary Gomso-Bay tidal deposits.

• Journal of Sericultural and Entomological Science
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• no.11
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• pp.15-22
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• 1970

This experiment is to investigate the influence on business by varying the scouring condition of raw silk. The conditions of experiment are changed by temperature, time concentration and scouring reagent as well as the pH value of scouring solution, involving the repeat number of treatment in the same reagent solution. The results are as follows. 1) The shorter the scouring time, the more lousiness showed on law silk. The difference of lousiness quantity are especially remarkable between 30 min. and 60min, while the appearance of lousiness is slight between 50min. and 90min. 2) The lousiness shape was just like splited end and short wool fiber type during than 60 min. scouring, and splited end and long wool fiber type was appeared during 120 min. scouring. 3) The seperation of threads on silk panel was difficult with undissolved sericin in case of lower than 90$^{\circ}C$ of scouring temperature, so that it was almost impossible to inspect lousiness. 4) In case of repeating one after another scouring in the same solution, the more number of treatment, the less sho wed lousiness. Little difference were appeared in the quantity of lousiness from first to eighth repeated scouring, while large difference of quantity was appeared between 8th and 9th repeated scouring. 5) The quantity of lousiness was also increased until scouring reagent (Marseilles soap) is added to 0.75％, but rather decreased with more than 0.75％ of soap. The most variety of lousiness quantity was occured when the concentration of soap is changed from 0.15％ to 0.20％. 6) The peculiarities of lousiness shape by the concentration of scouring reagent were as followings; most of lousiness are splited end short wool fiber type with lower wool fiber type with higher than 0.75％, and the mixture of both the former and the latter with 0.5％ concentration. 7) The quantity of lousiness by the kind of scouring reagent was the least with 5％ of Na$_2$CO$_3$ solution, and the most with the mixture of 0.25％ Marseilles soap and 0.25％ Na$_2$CO$_3$. 8) The more increased pH value, the more lousiness showed. The peculiarities of lousiness shape was the splited end and short wool fiber type, and the end and long wool fiber type with higher value of pH 11 because of the decreased strength of threads and the cutting of brin. 9) With the discussions mentioned the above, the scouring conditions to decrease the lousiness quantity are summarized as follows. (1) It is better to take the possible long time of scouring. (2) Temperature should be kept higher than 95$^{\circ}C$ for complete scouring. (3) It was the best to use 0.5％ of Marseiles soap as scouring reagent. (4) No good results were produced by using the mixture of scouring reagent. (5) The best pH range of scouring solution was 9.5 to 10.5.

• Food Science of Animal Resources
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• v.31 no.5
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• pp.731-740
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• 2011

This study was conducted to evaluate a quality comparison between Chuncheon Dakgalbi made from Korean native chickens (KNC) and that made from commercial broilers. Two Korean native chickens including Woorimatdag (KNCWoori) and Hanhyup3 (KNC-Hanhyup), and two commercial broilers including grades of 18 (Broiler-18) and 13 (Broiler-13) were slaughtered at 110, 70, 38, and 31 d of ages. Chuncheon dalkalbi was prepared by mixing/dipping the meat in chili pepper sauce; it was then packed with air-packaging (Air-P) and 30% $CO_2$-MAP (0% $O_2$/30% $CO_2$/70% $N_2$), and stored at $5^{\circ}C$ for 10 d. The results showed that the KNC group had a lower pH but a higher cooking loss compared with the broiler group (p<0.05). In a texture analysis, KNC-Woori had the highest shear force value among the breeds (p<0.05). For the fatty acid composition of the thigh, the KNC-Woori contained more total saturated acids, myristic acid, palmitic acid and stearic acid, but less total unsaturated fatty acids, linoleic acid and linolenic acid than other breeds (p<0.05). Also, the n6/n3 ratios of the KNC group (19.24 and 16.77) were higher than those of the broiler group (14.02 and 14.77) (p<0.05). The total acceptability scores of Dakgalbi made from the KNC group were decreased by sensory panelists. The Dakgalbi with 30% $CO_2$-MAP delayed the protein deterioration (Volatile basic nitrogen) and lipid oxidation during storage. However, no clear evidence was observed of $CO_2$-MAP on the effect of different chicken materials. It is suggested that 30% $CO_2$-MAP instead of Air-P is used for methods for Chuncheon Dakgalbi. Furthermore, it might be unfavorable to use Korean native chickens as raw material for Chuncheon Dakgalbi from a practical quality point of view.

• Food Science of Animal Resources
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• v.27 no.2
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• pp.179-184
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• 2007

The objective of this study was to investigate the contents of meat and non-meat ingredients, calorie, fatty acid composition, and cholesterol contents of processed meat products of which informations are being provided for consumer and partly required for the current labeling system in Korea. A total of sixty-one domestic processed meat products produced from 6 domestic meat companies were collected at the large supermarkets in Suwon city; 1) 31 ham products(3 loin hams, 6 press hams, 20 mixed press hams and 2 fish hams), 26 sausage products(15 pork sausages, 7 mixed sausages and 4 fish sausages) and 4 ground processed meat products. Soy protein and com starch were widely used as non-meat ingredients for the most of processed meat products. The contents of meat, protein, fat, cholesterol contents, and calories were 75-98, 12-23, 1-16%, 7-50 mg/100g, and 1,620-3,127 cal/g for ham products and 60-96, 5-17, 3-27%, 5-73 mg/100g, and 1,271-3,546 cal/g for sausage products, respectively. The saturated(SFA), monounsaturated(MUFA) and polyunsaturated fatty acids(PUFA) contents of ham products were 31-40, 44-53 and 60-72%, and those of sausage products were 17-38, 34-61, and 13-37%, respectively. The ranges of meat contents and nutritional compositions were considerably broad even in the same type of the meat products. Therefore, the labeling system of the nutritional facts for ham as well as sausage products is necessary to categorize the quality level and thus to give the nutritional information to consumer for better choice of products in market.

• The Journal of the Korean bone and joint tumor society
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• v.11 no.1
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• pp.46-53
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• 2005

Purpose: Bisphosphonates (BPs) are the analogues of endogenous pyrophosphates: they have been used in the treatment of skeletal diseases such as Paget's disease, osteoporosis, and tumorinducing ostelysis, and are used in treatment of osteolytic metastasis of breast cancer recently. They are also used as one of the therapeutic agents for metastasis of prostatic cancer of which metastasis makes the mixed nature of osteolysis and ostegenesis. Although the action mechanism of BPs are well known for diseases with excessive osteoclastic bone resorption, the direct effect of BPs has not been known yet. This study was intended to see the tumor suppression capability of Zoledronic acid(ZOL) using nude mouse with osteosarcoma. Materials and Methods: MG-63 and HOS osteosarcoma cell lines were used and the transforemed MG-63-GFP and HOS-GFP cells, which were made for detection under fluorescent light, were subcutaneously injected to make osteosarcoma. The five 6-week male mice were used for the experiment at each group. After the injection, mice were cultivated until tumor pieces grow up to $3{\times}3{\times}3$ $mm^3$ and ZOL of 120 ug/kg was subcutaneously injected twice a week. Sizes of tumor were measured twice a week and photographed under fluorescent light. Results: In in vivo test with HOS osteosarcoma cell lines, mean size of tumors was 2,520 $mm^3$ in control group and was 131 $mm^3$ in ZOL group, which showed 94% of reduction comparing with the control ; with MG-63 osteosarcoma cell lines, mean size of tumors was 2,866 $mm^3$ in control group and was 209 $mm^3$ in test group with 72% of reduction (p<0.05). Conclusion: In in vivo tests with nude mice, we suggest that ZOL has direct effect on osteosarcoma cells and it would be used as one of the therapeutic agents for osteosarcoma, especially to ZOL-sensitive osteosarcoma cells.