• Journal of the Korean Wood Science and Technology
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• v.38 no.4
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• pp.323-332
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• 2010

Petroleum-based adhesive resins have extensively been used for the production of wood panels. However, it is necessary to develop environmentally friendly adhesive resins due to the increase of manufacturing cost and the environmental issue, such as the emission of volatile organic compounds, of the pertroleum-based adhesive resins. This study was conducted to formulate environmentally friendly adhesive resins using by rapeseed flour (RSF), which is the by-product of bio-diesel produced from rapeseed, for replacing petroleum-based adhesives with them. To formulate RSF-based adhesive resins, RSF was hydrolyzed in de-ionized water, 1% and 3% sodium hydroxide solutions. As a crosslinking agent, PF prepolymers were prepared with 1.8, 2.1 and 2.4 mol formaldehyde and 1 mol phenol (1.8-, 2.1- and 2.4-PF), and then mixed with RSF hydrolyzates to complete the formulation of RSF-based adhesive resins. The RSF-based adhesive resins were applied to fabricate 3-ply plywood panels. The solid content of RSF-based adhesive resins were ranged from 26.08% to 36.12% depending on the hydrolysis condition of RSF and PF prepolymer type with a high viscosity. The tensile shear strength and wood failure of plywood fabricated with RSF-based adhesive resins exceeded a minimum requirement of KS standard for ordinary plywood regardless of the hydrolysis condition of RSF and PF prepolymer type. Formaldehyde emissions of the plywood panels fabricated with 1.8-PF and RSF hydrolyzates were lower than that of E0 specified in the KS standard. Based on the results, RSF might be used as a raw material of environmentally friendly adhesives for the production of plywood panels, but further researches - the increase of solid content of RSF-based adhesives for reducing press time and the microscopic observation of plywood specimen for identifying the relationship between tensile shear strength and the penetration of adhesives into wood structure - are required to commercialize the RSF-based adhesives.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.3
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• pp.137-144
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• 2002

To obtain the basic information about pedo-genetic properties and origin of the parent materials of "Yongil" series in Korea, this study was conducted. The soil characteristics such as chemical and sand particles of typifying pedon, and distributional patterns in the area were analysed. The typifying pedon of "Yongil" series was distributed on the top of rolling area in the eastern coastal area of Korea, Yonggan-ri, Heunghae-eup, Pohang-si, Gyongbuk province. The results are as follows; The "Yongil" series in Korea was distributed on the rolling hill under altituede of 50m, and was used for cultivated upland, and the total acreage about 376ha. The content of sand was more than 50%, however the clay content in the depth of 40~100cm of the soil profile rapidly increased. The medium sand (0.5~0.1mm in size) are dominant among sand fraction, but coarse one are rare. So the rate of medium to total sand was higher in IIB horizon as 0.62~0.76 than A and C horizons. The content of heavy minerals in medium sand was low as 1.0~6.6% and the ratio of quartz to feldspars was higher in Ap2 and B1 horizon as 1.7 than IIB horizon which had less than 1.39. The cumulative curves of sand particles in Yeongil series showed the well sorted and differ from residuum soils derived from sand stone, but similar to dune soils(Haeri series). So it could be deducted from this study that "Yeongil" series are aeolian deposits derived from aeolian materials and have bisequum profile; the upper part depth of 40cm was recent cover sand, the horizon of 40~100cm depth was developed in Pleistocene epoch from the same materials.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.104-113
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• 1991

This experiment was conducted to find the effect of calcium salts on the inhibition of 'Campbell Early' grape(Vitis labruscana B.) berry absicission induced by ethephon. Ethylene evolution, berry abscission rate, and fruit quality were examined. Several mineral contents were determinded in the berries and morphological changes of cells in abscission zone were also studied. 1. Calcium acetate($4.4-8.8g/{\ell}$) and calcium hydroxide($2.2-8.8g/{\ell}$) completely inhibited berry abscission when applied with ethephon 1,000 ppm while calcium chloride was less effective. 2. Ethylene evolution in the berries treated with ethephon alone reached to maximum peak one day after application. However, that peak in the treatment of ethephon with calcium acetate occurred 3 hours after application. 3. No decrease of ethylene production capacity was observed in the ethephon solution even when held up to 36 hours after preparation but the effect on berry abscission was significantly reduced. In contrast, ethylene production of the solution prepared with calcium acetate was greatly decreased along with the increase of holding time. The effect of calcium acetate in aged solution on the inhibition of berry abscission was not altered. 4. There were no differences in mineral contents such as Ca, Mg, and K between the berries sprayed with ethephon 500 ppm or not. Additional calcium accumulation was not found in the skin, flesh, and petiole of clusters sprayed with 3 kinds of calcium salts (1.5 g net Ca per liter) respectively when analyzed 2 weeks before maturity. 5. Ethephon (1,000 ppm) alone induced the development of abscission layer in petiole but those applied with calcium acetate (0.05 M) did not develop any distinct abscission layer 3days after treatment.

• 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.

• Radiation Oncology Journal
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• v.25 no.4
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• pp.261-267
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• 2007

Purpose: To evaluate the association between radiation pneumonitis and dose-volume histogram parameters and to provide practical guidelines to prevent radiation pneumonitis following radiotherapy administered for breast cancer including internal mammary lymph nodes. Materials and Methods: Twenty patients with early breast cancer who underwent a partial mastectomy were involved in this study. The entire breast, supraclavicular lymph nodes, and internal mammary lymph nodes were irradiated with a dose of 50.4 Gy in 28 fractions. Radiation pneumonitis was assessed by both radiological pulmonary change (RPC) and by evaluation of symptomatic radiation pneumonitis. Dose-volume histogram parameters were compared between patients with grade <2 RPC and those with grade ${\geq}$2 RPC. The parameters were the mean lung dose, V10 (percent lung volume receiving equal to and more than 10 Gy), V20, V30, V40, and normal tissue complication probability (NTCP). Results: Of the 20 patients, 9 (45%) developed grade 2 RPC and 11 (55%) did not develop RPC (grade 0). Only one patient developed grade 1 symptomatic radiation pneumonitis. Univariate analysis showed that among the dose-volume histogram parameters, NTCP was significantly different between the two RPC grade groups (p<0.05). Fisher's exact test indicated that an NTCP value of 45% was appropriate as an RPC threshold level. Conclusion: This study shows that NTCP can be used as a predictor of RPC after radiotherapy of the internal mammary lymph nodes in breast cancer. Clinically, it indicates that an RPC is likely to develop when the NTCP is greater than 45%.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.449-455
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• 1993

Vibrio vulnificus is a recentry recognized halophilic organism that may cause human infections. Patients infected with Vibrio vulnificus often have a history of exposure to the sea, suggesting that the organism may be common inhabitant of marine environment. In this studies 314 samples were collected from 9 sites of Chonnam coastal area, from April to Jun, 1993. Isolation rates of V. vulnificus were 7.1% in total samples, 33.3% in sea water, 55.5% in sediment, 1.7% in fish and shellfish, 6.3% in kitchen environment. In each areas of Chunnam V. vunificus were isolated from 3.6% to 11.4%. The isolation rates of V. vulnificus was correlated positively with organic matter and COD in sea warer and sediment. In sea water, Microorganism population were $4.5{\times}10^3{\sim}3.5{\times}10^5\;CFU/ml$, Vibrio strains were $1.8{\times}10^l4.6{\times}10^3\;CFU/ml$, Coliform bacteria were $1.9{\times}10^1{\times}3.7{\times}10^2\;CFU/100ml$. In sediment, Microorganism population were $4.8{\times}10^3{\sim}5.2{\times}10^5\;CFU/ml$. Vibrio strains were $1.9{\times}10^2{\sim}8.4{\times}10^4\;CFU/ml$, Coliform bacteria were $7.2{\times}10^1{\sim}9.9{\times}10^2\;CFU/100ml$.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.4
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• pp.207-217
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• 2011

In this study the complex formation reactions between uranium(VI) and 2,6-dihydroxybenzoate (DHB) as a model ligand of humic acid were investigated by using UV-Vis spectrophotometry and time-resolved laser-induced fluorescence spectroscopy (TRLFS). The analysis of the spectrophotometric data, i.e., absorbance changes at the characteristic charge-transfer bands of the U(VI)-DHB complex, indicates that both 1:1 and 1:2 (U(VI):DHB) complexes occur as a result of dual equilibria and their distribution varies in a pH-dependent manner. The stepwise stability constants determined (log $K_1$ and log $K_2$) are $12.4{\pm}0.1$ and $11.4{\pm}0.1$. Further, the TRLFS study shows that DHB plays a role as a fluorescence quencher of U(VI) species. The presence of both a dynamic and static quenching process was identified for all U(VI) species examined, i.e., ${UO_2}^{2+}$, $(UO_2)_2{(OH)_2}^{2+}$, and $(UO_2)_3{(OH)_5}^+$. The fluorescence intensity and lifetimes of each species were measured from the time-resolved spectra at various ligand concentrations, and then analyzed based on Stern-Volmer equations. The static quenching constants (log $K_s$) obtained are $4.2{\pm}0.1$, $4.3{\pm}0.1$, and $4.34{\pm}0.08$ for ${UO_2}^{2+}$, $(UO_2)_2{(OH)_2}^{2+}$, and $(UO_2)_3{(OH)_5}^+$, respectively. The results of Stern-Volmer analysis suggest that both mono- and bi-dentate U(VI)-DHB complexes serve as groundstate complexes inducing static quenching.

• Journal of Preventive Medicine and Public Health
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• v.14 no.1
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• pp.81-88
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• 1981

The present study was conducted to investigate the status of industrial injuries through a prospective study for a year from August 1980 to July 1981. The subjects were 15 textile industries which were selected by random sampling in Daegu. The results obtained are as follows: Anual over-all incidence rate of industrial injuries was 3.3 percent and the rate showed 6.7 percent in male and 2 percent in female. The rate showed decreasing tendency with larger scale of industries. By the age group, $15{\sim}19$ age group was the highest as 49.3 percent. Age specific incidence rate of industrial injuries revealed highest as 4.7 precent among the group the group of 30 years old and over. By the years of service, 57.1 percent of the total cases belonged to the the group less than 1 year and the rate revealed increasing tendency with shorter period of service. The highest frequency of industrial injuries was observed at the point of 3 hours after the beginning of the work in a day as 18.1 percent. Frequency of industrial injuries showed highest as 20.3 percent on Monday. Frequency of industrial injuries was highest as 27.7 percent in winter time and showed 14 percent and 11.8 percent in January and August, respectively. By the cause of injuries, machinery accidents showed the highest as 39.2 percent and followed by the accidents due to striking against object as 17.8 percent, fall of ground as 16.3 percent and hand tool as 7.2 percent. Frequency of injured parts of body was highest as 43.9 percent in fingers. The frequency was much higher in upper extremities (66.9%) than in lower extremities (17.6%). By the kind of injuries, laceration wound was highestas 35.7 percent and the next was superficial injury and contusion as 35.1 percent. By the duration of treatment, most of the cases was belonged to the group less than 1 month as 79.1 percent and the duration showed prolonging tendency with larger scale of industries.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.159-165
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• 1998

Purpose : The best prognosis for hepatocellular carcinoma can be achieved with surgical resection. However, the number of resected cases is limited due to the advanced lesion or associated liver disease. A trial of combined transcatheter arterial chemoembolization(TACE) and local radiotherapy(RT) for unresectable hepatocellular carcinoma(HCC) was prospectively conducted and its efficacy and toxicity were investigated. Materials and Methods : From 1992 to 1994, 30 Patients with unresectable HCC due either to advanced lesion or to associated cirrhosis were entered in the study Exclusion criteria included the presence of extrahepatic metastasis, liver cirrhosis of Child's class C, tumors occupying more than two-thirds of the whole liver, and an ECOG scale of more than 3. Patient cHaracteristics were : mean tumor size $8.95\pm3.4cm$, serum AFP+ in all patients, portal vein thrombosis in all patients, liver cirrhosis in 22 patients, and UICC stage III and IVA in 10 and 20 patients, respectively. TACE was performed with the mixture of Lipiodol(5ml) and Adriamycin(50mg) and Gelfoam embolizatin. RT(mean dose $44.0\pm9.3Gy$) 10 days with conventional fractionation. Results : An objective response was observed in 19 patients($63.3\%$). Survival rates at 1 2, and 3 years were $67\%,\;33.3\%$ and $22.2\%$, respectively. Median survival was 17 months. There were 6 patients surviving more than 3 years. Distant metastasis occurred in 10 patients, with 8 in the lung only and 2 in both lung and bone, Toxicity included transient elevation of liver function test in all patients, fever in 20, thrombocytopenia in 4, and nausea and vomiting in 1. There was no treatment-related death. Conclusion : Combined TACE and RT appear to produce a favorable response and survival results with minimal toxicity.

• Radiation Oncology Journal
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• v.14 no.3
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• pp.201-209
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• 1996

Purpose : To assess the efficacy of high dose rate - intracavitary radio-therapy (HDR-ICR) in the radiotherapy of FIGO stage IB squamous cell carcinoma of uterine cervix and to determine the optimum dose combination scheme of external radiotherapy and ICR to achieve acceptable local control without severe complication. Materials and Methods : One hundred and sixty two patients with FIGO stage Ib squamous cell carcinoma of uterine cervix who received definitive radiotherapy between May 1979 and December 1990 were retrospectively analyzed. All the patients received external radiotherapy combined with HDR-ICR. External dose of 40-46 Gy in 4.5-5 weeks was given to whole pelvis(median 45 Gy) and ICR dose of 30-39 Gy in 10-13 times was given to the point A. Midline shielding was done after 20-45 Gy of external radiotherapy(median 40 Gy) Summation of external dose Plus ICR dose to the point A range were 64.20-95.00 Gy. and mean was 83.94 Gy. We analyzed the local control rate, survival rate, and late complication rate. Rusults : Initial complete response rate was $99.4\%$ for all patients. Overall 5-year survival rate was $91.1\%$ and 5-year disease free survival rate was $90.9\%$. Local failure rate was $4.9\%$ and distant failure rate was $4.3\%$. Tumor size was the only significant prognostic factor. When tumor size greater than 3cm, 5-rear survival rate was $92.6\%$ and less than 3cm, that was $79.6\%$. Late complication rate was $23.5\%$ with $18.5\%$ of rectal complication and $4.9\%$ of bladder complication. Mean rectal dose summation of external midline dose plus ICR rectal point dose was lower in the patients without rectal complication(74.88 Gr) than those with rectal complication (78.87 Gy). Complication rate was increased with low rate of improvement of survival rate when summation of external midline dose plus point A or point R dose by ICR was greater than 70-75 Gy. Conclusion : The definitive radiation therapy using high dose rate ICR in FIGO stage IB uterine cervical cancer is effective treatment modality with good local control and survival rate without severe complication.