• Journal of the Korean Wood Science and Technology
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• v.38 no.4
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• pp.333-340
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• 2010

The Korean Dendropanax lacquer, made from a natural resinous sap from Dendropanax orbifera Lev., was used as a golden and transparent varnish for the traditional artifacts (armor uits, helmets, arrowheads, etc.) to make them be brilliant golden color. The cured film of the acquer has excellent protective properties such as weatherability, water resistance, and nticorrosive. But, one of disadvantages is that takes a long time and much energy to fulfill curing the lacquer. The chemical constituents of the lacquer contained conjugated diene compounds s the photopolymerizable monomers. These monomers easily polymerized in sunlight to form olden-colored, hard-coating films in a short time. Photooxidation may be one of the most mportant reactions in the chemistry of the lacquer. Although the Korean Dendropanax Lacquer hould be dried to a thoroughly dry stage to achieve optimal film properties, curing with elevated emperatures may be required for the protracted curing time at atmospheric temperature. So we ntended to accelerate the curing rate of the lacquer by dual curing of thermal and radiation uring. The effect of thermal initiator on the thermal curing reaction was evaluated by monitoring he changes in double bond peak with FT-IR. Then the curing rate of the lacquer blended with hermal initiator and photoinitiator together was measured during dual curing using a RPT with V spot curing machine. Thermal initiator not only accelerated the curing rate but also improved he physical property. And the curing rate of the Korean Dendropanax lacquer was improved by ual curing method of thermal and UV curing. According to these results, the application area of he Korean Dendropanax lacquer could be expanded to surface coatings for electronic devices uch as mobile phones or electronics.

• Korean Journal of Ecology and Environment
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• v.38 no.3 s.113
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• pp.361-371
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• 2005

The objective of study was to diagnose integrative ecological health of Daejeon Stream, one of the tributaries of Guem River, during May 2004 ${\sim}$ April 2005. The research approach was primarily based on a Qualitative Habitat Evaluation Index (QHEI) and the Index of Biological Integrity (IBI) using fish assemblage. These outcomes were compared with conventional chemical dataset. For the experiment, four sampling sites were chosen from Daejeon Stream and long-term water quality data during 1995 ${\sim}$ 2004 (obtained from the Ministry of Environment) were analyzed in the spatial and temporal aspects. For the biological health assessment, we developed a stream health assessment model (SHA model) far regional applications. We found that current water quality conditions, based on the COD, BOD, TN and TP, were enhanced by 1.6 ${\sim}$ 5.3 fold over the period of 1995 ${\sim}$ 2004 and that the parameters showed a typical longitudinal decline from the upstream to downstream reach. The differences of water quality between the two reaches were more than 4.4 times, indicating a large spatial variations within the stream. The health conditions, based on the SHA model, averaged 23 and varied from 20 to 26 depending on the sampling stations. Values of the QHEI varied from 39 (Poor condition) to 124 (Cood condition)and values of QHEI in the reach of S2 ${\sim}$ S4 had significantly lower than in the headwater site (S1). Also, biological stream health, based on the criteria of US EPA (1993), was judged as 'Poor condition', in the S4 where TN, TP, BOD and COD were highest. In the meantime, maximum value of SHA (26) was found in the upstream reach (S1) where the water quality and QHEI were best. We also found that compositions of sensitive species showed a linear function with water quality conditions and this pattern was evident in the tolerant species. Thus, the biological stream health, based on the SHA model, matched well water chemistry. Overall outcomes suggest that the biological health impact was a function of chemical degradation and physical habitat quality in the stream.

• Korean Journal of Ecology and Environment
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• v.39 no.2 s.116
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• pp.198-208
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• 2006

This research was to apply a multi-metric approach, so called the Index of Biological Integrity (IBI) as a tool for biological evaluations of water environments, to a wadable stream. For the study, we surveyed 5 sampling locations in Kap Stream during August 2004 ${\sim}$ September 2005. We also compared the biological data with long-term water quality data, obtained from the Ministry of Environment, Korea and physical habitat conditions based on the Quantitative Habitat Evaluation Index (QHEI). We used ten metric systems for the IBI model to evaluate biological stream health. Overall IBI values in Kap Stream averaged 24 (range: 20${\sim}$30, n=5), indicating a "fair ${\sim}$ poor" conditions according to the modified criteria of Karr (1981) and US EPA(1993). Exclusive of 4th survey, average IBI values at the upstream reach (S1 ${\sim}$ S3)and downstream reach (S4 ${\sim}$ S5) were 20 and 24, respectively. However, in 4th survey the averages were 21 and 20 in the upstream and downstream reaches, respectively. This difference was larger in the upstream than in the downstream because of physical condition disturbed during summer monsoon. Values of the QHEI varied from 75(fair condition) to 148 (good condition) and values of QHEI in the S3 were significantly (P=0.001, n=5) lower than other sites. Biochemical oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) were greater by 3 ${\sim}$ 8 fold in the downstream than in the upstream reach. We believe that present IBI approach applied in this study may be used as a key tool to set up specific goals for restoration of Kap Stream.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.5
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• pp.418-428
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• 2007

Physical and chemical properties of the aggregate by-products including sludge and crushed dust samples collected from the 21 private companies throughout the country were analyzed to evaluate possible usage of the by-products as artificial soil materials for plantation. The pH of the materials ranged from 8.0 to 11.0. The organic matter content was $2.85g\;kg^{-1}$, and the total nitrogen content and available phosphate content were low as 0.7 percents and $12.98mg\;kg^{-1}$, respectively. Exchangeable $Ca^{2+}$, $Mg^{2+}$, $K^+$, and $Na^+$ were 2.29, 0.47, 0.02 and $0.05cmol\;kg^{-1}$, respectively. Heavy metal contents were lower than the limits regulated by environmental law of Korea. Textural analysis showed that most of the materials were silt loam with low water holding capacity ranged from 0.67 to 7.41 percents, and with low hydraulic conductivity ranged from 0.4 to $2.8m\;s^{-1}$. Mineralogical analysis showed that the aggregate by product materials were mostly composed of silicate, alumina and ferric oxides except calcium oxide dominant materials derived from limestones. The primary minerals were quartz, feldspars and dolomites derived from granite and granitic gneiss materials. Some samples derived from limestone material showed calcite and graphite together with the above minerals. According to the result, it can be concluded that the materials could be used as the artificial soil material for plantation after proper improvement of the physico-chemical properties and fertility.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.268-274
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• 2010

The properties of upland soils are much more dependent upon topography than those of paddy soils, and they give us very useful information to manage the upland fields. Therefore, we investigated the selected physical and chemical properties of upland soils at 84 and 150 topographic sampling sites, respectively. The topographic sites included 34.7% of local valley and fans, 18.7% of hilly and mountains, 20.0% of mountain foot slopes, 14.0% of alluvial plains, 8.0% of diluvium, and 4.6% of fluvio-marine deposits. Based on the investigation, soil textures in Jeonbuk upland fields were mostly sandy loam, sandy clay loam, clay loam, and clay soils, especially sandy clay loam soils were evenly distributed in all of the topographic sites. Soil slopes in the sites ranged from 0 to 15%, which showed an optimal condition for farm land. Soil bulk density and compaction values were from 1.19 to 1.24 g $cm^{-3}$ and from 12.1 to 13.9 mm, respectively. As comparing with the optimal conditions of soil chemical properties for upland soils proposed by National Institute of Agricultural Science and Technology, Korea, 37%, 42.7%, 93.0% of the sites were within optimum levels with soil pH, content of soil organic matter, and electrical conductivity, respectively. However, 64.0%, 47.3%, 48.7%, and 42.7% of the upland soils contained excess levels of exchangeable K, Ca, and Mg, and available phosphorus, respectively. In addition, the contents of heavy metals, As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn, in the Jeonbuk upland soils were much less than threshold levels.

• Journal of Veterinary Clinics
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• v.10 no.2
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• pp.171-184
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• 1993

In Seoul area, there are so many kennel clubs, veterinary hospital, pet establishment and breeding confers that various problems have occurred. They are crowed pet houses, poor sanitation, stress to puppies, sudden environmental changes to puppies and unvaccination against parvovirus, canine distemper virus, parainfluenza virus, infectious hepatitis caused by Adenovirus type I and Leptospira. Several studies were made to survey the infectious agents involved in acute diarrhea of poppies in Seoul are, such as history taking, physical examination, complete blood count and serum chemistry, histopathological finding, bacterial isolation and identification, and hemagglutination test in feces and hemagglutination inhibition test in serum against parvovirus, respectively. The results obtained are summarized as followed. 1. The percent of PCV (30.5$\pm$5.6) and concentration of Total protein(5.0$\pm$0.8) resulted from statistical analysis are significantly lower than normal values (p<0.05), respectively. In addition, fibrinogen (505$\pm$326) was significantly higher an normal value (p<0.001), Band neutrophil (22.9$\pm$12.7) showed signifiant difference (P<0.01). decreased monocyte (3.2$\pm$2.1) and eosinophil (0.7$\pm$0.8) values appeared statistically significant (p<0.001), lymphocyte (16.7$\pm$9), as well. 2. The concentrations of calcium .(8.0$\pm$2.8), glucose (40.1$\pm$31.4), and albumin (2.0$\pm$0.39) were lower than normal values (p<0.01, p<0.01, p<0.001), respectively. Also Inorganic phosphate (7.1$\pm$2.4), pH (p<7.9f:0.2), and Blood Urea Nitrogen (40.41=37.1) were significantly higher than normal values (p<0.001, p(0.001, p<0.05), respectively. 3. Simple and mixed infections occupied 18% and 82% in the distribution of causes in puppies with acute diarrhea, respectively. 4. As puppies got older, incidence of acute diarrhea caused by Staphylococcus aureus was decreased to 13% and infection of canine distemper virus was increased to 53%, but E coli and canine parvovirus always showed high frequency of outbreak in the body weight ranged from 35g to 7.8Kg. 5. As showed in table 5, infections of E coli and Canine Parvovirus showed high outbreak regardless of the age which is classified into three stages, 35~50 day, 60 day and 75~day to 1 year, canine distemper virus appeared increased, but in case of Staphylococcus aureus, visa versa. 6. In comparison wi methods for the laboratory diagnosis diagnosis parvovirus, Hemagglutination test showed positive reaction in 25% and mean serum antibody titer measured by Hemagglutination inhibition test showed 2779 (n=20). In addition, positive reaction was 90% (18/20). 7. In histopathological studies, enteritic and pneumonic lesions were indicated in 53.7% and 39.5% of samples, respectively. 8. Etiologic diagnosis based on the history taking, clinical signs and histopathological findings in puppies with acute diarrhea and vomiting indicated that 50% of puppies were infected by canine parvovirus and distemper virus. 9. In the parasitological examination made by simple flotation with saturated zinc sulfate tour parasites found were Isospora canis, Toxocara canis, Ancylostoma spp and Toxocara spp. Isospora canis and Toxocara canis were more frequently found among those parasites of diarrhoeic causes in puppies ranged from 35 days to 1 year. Their infestation rates were 15% and 13% respectively.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.211-217
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• 1997

The physical and chemical stability of anthocyanins from a Korean pigmented rice variety was investigated at various conditions of pH, temperature, metal ion, sugar, organic acid and light. The anthocyanin pigments were relatively stable with half-lives of 36 days (pH 2.0) and 17 days (pH 3.0), while they were decomposed in a day at neutral and basic pH of 7.0 and 9.0 at $25^{\circ}C$. The anthocyanins also showed high thermal stability at pH 3.0; the half-lives were 7.4 hr, 23.6 hr and 96.3 hr at $95^{\circ}C,\;75^{\circ}C\;and\;50^{\circ}$, respectively. Addition of di- and tri-valent metal ions at pH 3.0 resulted in the increase of color intensity and stability throughout 21 days of storage periods at $25^{\circ}C$. Most sugars added accelerated the degradation of anthocyanin pigments, so that fructose showed the greatest degradation effect on the pigments. Addition of citric acid at pH 3.0 increased stability of anthocyanins, while tartaric acid decreased stability. The anthocyanins were very sensitive on light irradiation with a degradation half-life of 14 hr under 20,000 lux-light dosage at pH 3.0.

• Clean Technology
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• v.17 no.1
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• pp.48-55
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• 2011

The application of fibrous activated carbon (FAC)-titanium dioxide ($TiO_2$) hybrid system has not been reported yet for the control of malodorous dimethyl sulfide (DMS) at residential environmental levels. Accordingly, the current study was designed not only to characterize this hybrid system using x-ray diffraction method, particulate surface measurement and Fourier transform Infrared (FTIR) method, but also to evaluate its adsorptional photocatalytic activity (APA) for the DMS removal. The physical/surface characteristics of FAC-$TiO_2$ which was prepared in this study suggested that the hybrid material might have certain APA for DMS. The Brunauer-Emmett-Teller (BET) specific area, total pore volume, micropore volume and mesopore volume decreased all as the $TiO_2$ amounts coated on FAC increased, whereas the reverse was true for average pore diameter. $TiO_2$ coated onto FAC did not influence the adsorptional activity of FAC for the DMS input concentration of 0.5 ppm. The APA test of the hybrid material presented that the initial removal efficiencies of DMS were 93, 78, 71 and 57% for the flow rates of 0.5, 1.0, l.5 and 2.0 L/min, respectively, and they decreased somewhat 2 h after the experiment started and kept almost constant for the rest experimental period. Under this pseudo-equilibrium condition, the DMS removal efficiencies were 78, 58, 53 and 36% for the four flow rates, respectively. Meanwhile, there were no significant byproducts observed on the surfaces of the hybrid material. Consequently, this study suggests that, under the experimental conditions used in the present study, the hybrid material can be applied for DMS at residential environment levels without being interfered by any byproducts.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.438-445
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• 2010

Soils in continuous monoculture cropping system generally have a number of physical and chemical problems. Thus, we studied to investigate selected soil properties in continuous watermelon cropping plots with applications of different soil management practices: 1) conventional farming practice (CFP), 2) chemical fertilizer management practice (FMP), the FMP with different amounts, 0.5, 1.0, and 1.5 t $ha^{-1}$, of oyster shell meal application (FMP-OS 0.5, 1.0, and 1.5 t $ha^{-1}$), and 3) the FMP with different amounts, 2.0, 3.0, and 4.0 t $ha^{-1}$, of peat application (FMP-PT 2.0, 3.0, and 4.0 t $ha^{-1}$) and also to evaluate watermelon quality. Soil pH slightly increased only in the FMP-OS 1.5 t $ha^{-1}$ plot, while it was not changed or decreased a little in other plots. The contents of soil organic matter (SOM) expectedly increased in the FMP-PT plots, whereas it markedly decreased in the FMP-OS plots. The concentrations of exchangeable cations, $Ca^{2+}$, $Mg^{2+}$, and $K^+$, in soils were mostly dropped down in most of the FMP and FMP-PT plots. Otherwise, the exchangeable $Ca^{2+}$ concentration increased a bit in the FMP-OS plots. Also, the concentrations of water-soluble anions, $NO_3^-$, $Cl^-$, ${SO_4}^{2-}$, and ${PO_4}^{3-}$, in soils mostly declined in all the plots applied with the different management practices during the study years. Due to the cation and anion decreases, the electrical conductivity (EC) values in the soils were greatly reduced in the plots. Thus, the soil management practices applied, especially oyster shell meal and peat treatments, might be useful to control soil conditions. However, watermelon quality, such as sugar content and fruit weight, would not be associated with the soil management practices applied.

• Journal of agricultural medicine and community health
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• v.21 no.2
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• pp.173-193
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• 1996

This study was carried out to elucidate the causes of farmer's disease and greenhouse disease in the rural area of Kyungnam province during 1996. 2,171 (69.1%) of the 3,140 adults above 20 years old who had lived in the selected 20 villages in Uiryong County of Kyungnam Province were selected in order to over both residents who live in the green house distracts and conventional rural area. The results were as follows: 1. Among the subjects, the male was 42.2% and female was 57.6%. The average age for the male was 52.3, 55.6 for the female. 2. The proportion of the farmers in the subjects was 81.5%. Among these 78.0% were engaged in the greenhouse farming. 3. Among the eight symptoms of Nofusho(japanese farmer's comples), lumbago was the most frequently complained and followed by shoulder stiffness and parenthesis of hand or foot. 4. The total score of farmer's disease was evidently higher in the female and the older the score was clearly bigger. 5. The prevalence of Nofusho(Japanese farmer's comples)was 26.8% and 43.15% was for the suspected Nofusho. In the male, the prevalence of Nofusho was 13.6% and 40.9% for the suspected Nofusho and in the female 36.5% and 44.7% were shown, comparatively. 6. According to the multiple classification analysis, sex, age, and occupation were selected as significant variables to explain the total score of Nofusho. 7. The correlations between the total score of Nofusho and the number of sick day, working years, and age were significant, comparatively. 8. According to the multiple classification analysis corolling interaction between independent variables, age was the only variable which was significant in the male and age, pesticide work in the female. 9. The score of greenhouse disease was highest in the group who engaged in greenhouse farming and conventional farming(2.76 for male, 3.77 for female) followed by the group who engaged only in greening house farming(2.66 for male, 3.49 for female) and by the group who engaged only in conventional farming(2.27 for male, 3.05 for female) 10. According to the multiple classification analysis with the total score of greenhouse disease as dependent variable, corolling interaction between independent variables, age and pesticide work were revealed as significant variables in the male, while, pesticide work and farming type were significant in the female. According to the above results, the following could be suggested. Because lumbago, shoulder stiffness, paresthesia of hand and foot were the most frequently complained symptoms in the respondent, the development of farming tool to reduce the body burden and periodical physical exercise and rest is highly recommended. It is revealed that both in the farmer' disease and greenhouse disease the score was higher in the female than in the male. So the reasonables measures is recommended to reduce the working hours of the female. Pesticide work was revealed as the significant variable in the female in farmer's disease and both in the male and the female in greenhouse disease. So the development of the safe method of pesticide spraying including safety education should be introduced. Particularly the female should be excluded in pesticide spraying.