• Journal of environmental and Sanitary engineering
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• v.14 no.3
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• pp.63-70
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• 1999

A study on the zeolite synthesized of bituminous coal fly ash from power plant has been carried out to reuse industrial waste. The synthesized zeolite was proved to be 4A type by means of the X-ray diffraction analysis and the degree of crystallinity was found to be higher than 90%. Then the synthesized zeolite was used as an adsorbent to remove the heavy metal ions in the CU, Pb, and Cd containing wastewater and water. Also, adsorption characteristics and kinetics of synthesized zeolite in the each metal ion solutions were studied. In each ion solutions, the adsorbed amounts of Pb, Cd, and Cu to the unit weight of synthesized zeolite were 141.6, 118.8, and 131.4mg/g respectively when each metal ion concentration was 500mg/L solution. The adsorption kinetics was fitted well to the Freundlich isotherms. The value of l/n for Pb, Cd, and Cu and 0.27, 0.50, and 0.66, respectively. Those results showed that the synthesized zeolite could be used as an adsorbent to remove single heavy metal ions in the wastewater and water. The heats of adsorption, H values of Pb, Cd, and Cu were 4.87, 14.95, and 18.23kacl/mol by the Henry-van't Hoff equation.

• Composites Research
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• v.18 no.4
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• pp.8-13
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• 2005

Rotating circular disks are widely used in data storage devices as well as in traditional industrial machines. Faster rotating speed is required in data storage devices for higher data transfer rate. In this Paper an application of composite materials to CD is proposed to increase critical speeds and the strength analysis was performed. A differential equation of displacement is derived for the analytic stress distribution of rotating polar orthotropic disk. The stress distributions for typical GFRP and CFRP disks and the maximum allowable speeds subjected to a constraint of tensile strength are presented in addition to polycarbonate disk. The results show that the application of CFRP to rotating disk can increase the maximum allowable rotating speed but this may not be applicable to GFRP disk.

• Journal of Nutrition and Health
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• v.32 no.7
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• pp.781-786
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• 1999

This study was designed to investigate the effects of vitamin E supplementation on radical scavenger activity and immune responses in female judo athletes(n=18). The age and sex matched sedentary students were used as controls(n=15). The initial plasma vitamin E concentration, lipid peroxide level and radical scavenger activity (RSA) were not different between two groups. The supplementation of $\alpha$-tocopheryl acetate(400IU/d) for 4 weeks significantly increased plasma vitamin E concentration of the subjects in both groups. In addition, the decrease in thiobarbituric acid reactive substance(TBARS)(p<0.05) and enhancement of RSA(p<0.05) were observed in both groups. Percentages of total T-cells in the athletic group was lower than that in the control group(p<0.05). However, the ratio of CD4 / CD8(helper T-cal $l^pressor T-cell) was higher in the sports group, due to more decrease in CD8 subset than in CD4 subset. The concentrations of IgG and IgM in the sports group were significantly lower than those in the control group(p<0.05). Therefore, severe training of the athletic group seems to be associated with the changes of supplementation. In conclusion, vitamin E supplementation (400IU/d, 4 weeks) of the female university students improved antioxidative activities of the blood, by decreasing lipid peroxide and enhancing radical scavenger activity. Percentages of T lymphocytes and IgG and IgM concentrations in the athletic group were lower than those in the control group. Meanwhile, vitamin E supplementation had no effects on immune status in both groups.ps.

• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.353-358
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• 2007

The publications on dietary intake, respiratory intake and blood concentration of cadmium and lead in some Korean women are reviewed. Reported values of dietary Cd intake as geometric mean were $17.1{\mu}g/day$ in 1986, $21.2{\mu}g/day$ in 1994, $16.7{\mu}g/day$ in 2000, and blood concentration were $1.45{\mu}g$ in 1986, $1.27{\mu}g/l$ in 1994 and $2.74{\mu}g/l$ in 2000, respectively. In case of Pb, the dietary intake were $33.1{\mu}g/day$ in 1986, $20.5{\mu}g/day$ in 1994, and $18.4{\mu}g/day$ in 2000 and the blood concentration were $51.5{\mu}g/l$ in 1986, $44.3{\mu}g/l$ in 1994, $37.3{\mu}g/l$ in 2000, respectively. Dietary intake is an almost exclusive route of Cd exposure, however respiratory intake in case of Pb is thought to affective exposure route in Korean women. When compared with the values reported in the literature, both of dietary Cd and Pb intake levels appear to be similar to or somewhat higher than the levels in east and south-east Asia.

• Journal of Environmental Science International
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• v.10 no.1
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• pp.27-33
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• 2001

In order to study the long-term change of heavy metal concentrations in the Kumho river water, water analysis was conducted at 13sites surrounding the Kumho river system for 18times from September 1993 to August 1999. Analytical items for the study of water quality are Cu, Zn, Cd, Cr, Fe, Mn and Pb. The six year term studied in this work was divided into Part I and Part II, which covers the period from September 1993 to August 1996 and the period from September 1996 to August 1999, respectively. The mean concentrations of Cu, Zn, Cd, Cr, Fe, Mn and Pb in the unit of ppm for the Part I period showed 0.032, 0.025, 0.006, 0.050, 0.053 and 0.019, respectively. The mean concentrations of Cu, Zn, Cd, Cr, Fe, Mn and Pb in the unit of ppm for the Part II period showed 0.001, 0.001, 0.001, 0.004, 0.020, 0.002 and 0.002, respectively. The heavy metal concentrations in the Kumho river water for te second period were found to be decreased by 1/32, 1/25, 1/6, 1/1.5, 1/2.5, 1/26.5 and 1/9.5 for Cu, Zn, Cd, Cr, Fe, Mn and Pb, respectively. The present results clearly indicate that the water quality in the Kumho river is improving in terms of heavy metal contaminations.

• Journal of Acupuncture Research
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• v.18 no.1
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• pp.29-39
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• 2001

Purpose : It has been reported that Oyo-Tang has an effect on allergic asthma clinically. In order to investigate the herbal acupuncture solution of the Oyo-Tang on allergic asthma, the Oyo-Tang herbal-acupuncture(OTHA) was applied on BL13 and ST36 of allergic asthma model of the rats. Methods : Then the concentration of serum IgE and the ratio of CD4+ and CD8+ T-cells in peripheral blood were measured and compared with control group. Results : The results obtained as follows; 1. The concentration of serum IgE was decreased significantly in both of the OTHA on BL13 group and on ST36 group as compared to control group. 2. The ratio of CD4+ and CD8+ T-cells in peripheral blood was not different statistically between the normal, the control, the OTHA on BL13 and the OTHA on ST36 group.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.984-987
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• 2003

The electrophosphorescent emission properties were investigated in polymer light-emitting diodes (PLEDs) based on a poly(9-vinylcarbazole) (PVK) doped with a green phosphorescent dye of fac-tris(2-phenylpyridine) iridium (III) [$Ir(ppy)_3$]. A green light peaked at 516 nm was emitted from devices with a configuration of ITO/PEDOT:PSS/PVK:$Ir(ppy)_{3}$/BCP/$Alq_{3}$/LiF/Al. The optimal doping concentration of $Ir(ppy)_{3}$ in PVK was found at 2% by weight, under which maximum current efficiency of 24.3 cd/A and peak external quantum efficiency of 6.8% were achieved at the high luminance of 4240 $cd/m^{2}$. The external quantum efficiency of 5% and current efficiency of 18 cd/A can be sustained even at the very high luminance of 35000 $cd/m^{2}$.

• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.551-554
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• 2008

An improved HPLC method for the separation of madecassoside isomers (madecassoside and asiaticoside-B) has been developed. The isomers can be separated with high resolution from extracts of Centella asiatica by HPLC using $\beta$-cyclodextrin as a mobile phase added on a $C_{18}$ column. The result shows that the isomers can be separated with a mobile phase consisting of methanol:water (50:50, v/v) with 4 mmol/L $\beta$-CD. To elucidate the mechanism of the separation of madecassoside and asiaticoside-B, this paper studied the separation of their aglycon parts (madecassic acid and terminolic acid), another pair of isomers. The isomers can also be separated with high resolution with a mobile phase consisting of methanol:water (65:35, v/v) with 4 mmol/L $\beta$-CD and the pH of the mobile phase was adjusted to 4. The paper also studied the separation of the two isomers by HPLC using $\alpha$-CD and Glucosyl-$\beta$-CD as a mobile phase additive in order to elucidate the mechanism of the separation process.

• Journal of Environmental Health Sciences
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• v.26 no.2
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• pp.116-121
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• 2000

This study was performed to investigate the heavy metal contents and distribution in bioorganisms from the estuary area of Mankyeong-Dongjin river. In paddy plant, the average contents of heavy metals were in order of Zn>Cu>Pb>Cr>Cd in all parts. Those of Cd, Cr, Pb and Cu were all highest in the leaf while lowest in the brown rice. The average content of Zn was almost similar in all parts. In the dried muscular parts of shellfish, the average contents of heavy metals were in the range of 1.06~1.95 mg/kg for Cd, 2.93~4.98 mg/kg for Cr, 0.90~1.17 mg/kg for Pb, 8.41~18.58 mg/kg for Cu and 29.81~67.31 for Zn, respectively, In fish(Acanthogobius hasta), the average contents of heavy metals in the dried body parts were in the range of 0.05~0.43 mg/kg for Cd, 0.65~4.59 mg/kg for Cr, 1.01~4.75 mg/kg for Pb and 1.34~4.19 mg/kg for Cu, with high accumulation in bone and head overally.

• Child Health Nursing Research
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• v.29 no.3
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• pp.218-228
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• 2023

Purpose: This study aimed to identify clinical characteristics of South Korean pediatric inflammatory bowel disease (IBD) in a children's hospital over the past 5 years, with a specific focus on comparing the features observed between Crohn's disease (CD) and ulcerative colitis (UC). Additionally, it aimed to examine the nursing diagnoses given to patients. Methods: This retrospective study analyzed the medical records of Korean pediatric patients under 18 years of age who were diagnosed with IBD and hospitalized at a children's hospital in Seoul, South Korea, from January 2017 to December 2021. Results: The number of pediatric patients diagnosed with IBD steadily increased. This finding was particularly prominent for CD patients, the majority of whom were male. Pediatric patients with CD had significantly higher rates of abdominal pain and perianal lesions, while pediatric patients with UC had a higher rate of bloody stool. Laboratory findings indicated that CD patients had higher levels of inflammatory markers and lower albumin levels than UC patients. The nursing diagnoses given during hospitalization mostly related to safety and protection, physical comfort, and gastrointestinal function. Conclusion: This study provides insights into Korean pediatric IBD patients, enabling early detection and the development of nursing intervention strategies. From a comprehensive perspective, nursing care should not only address patients' physical needs but also their psychosocial needs.