• Title/Summary/Keyword: pb group

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Characteristic Analysis of Chemical Compositions for Ancient Glasses Excavated from the Sarira Hole of Mireuksaji Stone Pagoda, Iksan (익산 미륵사지 석탑 사리공 내 출토 고대 유리 유물의 성분특성 분석)

  • Han, Min Su
    • Journal of Conservation Science
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    • v.33 no.3
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    • pp.215-223
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    • 2017
  • The purpose of this study is to reveal the characteristics, correlations, and colorant materials of those using the chemical compositions of 30 glasses excavated from the Sarari hall of the Mireuksaji stone pagoda, and to determine the correlations between them and other glass excavated from the Wanggungri site. The results of the chemical analysis of the 11 glass beads show that they are a soda glass group with high contents of $SiO_2$ and $Na_2O$; these can be further subdivided into soda-alumina groups ($Na_2O-Al_2O_3-CaO-Si_2O$). The characteristics of the stabilizer are classified as being of the high alumina glass group (LCHA), except for two glasses. It was concluded that colorant materials affected the coloring for glass beads by various components including Ti, Mn, Fe, Cu and Pb. In addition, we examined six lead glasses which are glass plate and unknown fragments that are of a common lead glass system ($PbO-SiO_2$) with respect to the average contents of PbO (70wt.%) and $SiO_2$ (30wt.%). As a result of comparing these relics with those of the glass beads excavated by Wanggungri, there is a similarity in that they belong to the soda glass group. However, the contents of $Na_2O$ are relatively higher than that of the glass beads in the Mireuksaji pagoda, and most of relics include glasses with a low content of $K_2O$ and CaO. In addition, the PbO and $SiO_2$ contents are slightly different in the lead glass. It seems that the glass relics made at two different sites may have used different raw materials or techniques.

Effects of Ethanol on the Subacute Lead Poisoning in Rats (흰쥐에서 아급성 연중독에 미치는 에탄올의 영향에 관한 연구)

  • 이용욱;박성관;이선동
    • Journal of Environmental Health Sciences
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    • v.21 no.3
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    • pp.56-66
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    • 1995
  • This study was performed to investigate the effects of Ethanol on the lead poisoning in rats. For this experiment, 48 male Sprague-Dawley strain were used. The experimental groups were divided into six: a normal control(Control), 200 mg/kg b.w. lead(Pd), 5% ethanol(E5), 10% ethanol(E10), 200 mg/kg b.w. lead plus 5% ethanol(PE5) and 200 mg/kg b.w. lead plus 10% ethanol(PE10). Lead was dissolved in the distilled water and administered orally. Ethanol was given with drinking water ad libitum. The rats were allocated to each group by 8 and sacrificed for 5 weeks. The results were as follows: 1. The mean body weight of each group were increased constantly in all groups during experimental period, but the values of ethanol treatment groups were higher than that of control (Control), lead treatment group(Pb) (P<0.01). 2. Compared to Control and Pb, the relative weight of liver and brain were increased in all the ethanol fed groups. But the relative weight of organs were not observed significantly. 3. The lead concentration of organs were high in the group treated with lead(Pb, PES, PE10) (P<0.01), and PE5, PE10 were high compared with Pb in brain especially(P<0.01). However, no statistical significance were showed between PE5 and PE10. 4. The concentration of serum ALT was increased by lead plus ethanol (PE5, PE10) significantly (P<0.01). 5. The concentration of Hematocrit, hemoglobin, WBC and RBC were not observed difference significantly in all groups.

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Influence of Consumption Patterns and Satisfaction for Convenience Store Private Brand Foods (편의점 PB식품군 구매행동 및 만족도 영향요인 연구)

  • Kim, Min-Jeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.3
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    • pp.629-637
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    • 2016
  • This study examined the purchasing behavior and satisfaction of people with convenience store PB foods. The factors affecting the purchasing behavior and the overall satisfaction with the convenience store PB foods were examined. This study first found that the purchasing motivation of PB foods is the cheaper price than NB foods. Second, age is a statistically effective variable for the visit frequency at the convenience store and gender and age are effective variables for the purchase frequency of PB foods. Third, there is a statistically positive correlation of convenience store brand preference with the PB food brand preference for 6 food categories. Next, in terms of the attribute-level satisfaction, the most satisfied areas are diverse food groups and diverse food taste and the least satisfied areas is price. This is followed by taste and design/packaging influence overall satisfaction. From this analysis, the following suggestions were drawn. First, because consumers are likely to be matched convenience store brand preference and PB food brand preference, advertising is necessary to ensure that the consumers continue to visit the convenience store. Second, product improvement by increasing the quality should be designed to motivate the major consumer group of people in their 20s and 30s. Finally, to boost PB food satisfaction, the industry should improve the taste and design/packaging.

Structure and Dielectric Properties of PMN-PNN-PZT ceramics (PMN-PNN-PZT 세라믹스의 구조 및 유전특성)

  • Lee, Jong-Deok;Park, Sang-Man;Park, Gi-Yup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05c
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    • pp.257-260
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    • 2003
  • In this study, the structural, dielectric and piezielectric properities of $xPb(Mg_{1/3}Nb_{2/3})O_3-(0.5-x)Pb(Ni_{1/3}Nb_{2/3})O_3-0.5Pb(Zr_{0.3}Ti_{0.7})O_3$ ceramics were investigated with the substitution of $PbMg_{1/3}Nb_{2/3}O_3$. The results showed that the substitution of the $PbMg_{1/3}Nb_{2/3}O_3$ was effective in increasing the dielectric constant and electromechanical coupling factor $(K_p)$. The dielectric constant, dielectric loss and Kp showed the highest values of 4293, 2.4%, 0.59 relatively, when the substitution of amount of $PbMg_{1/3}Nb_{2/3}O_3$ was 5 mol%.

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Concentration and Geochemical Phases of Heavy Metals in Marine Sediments in the Vicinity of the Coal-fired Power Plant of Korea (석탄화력발전소 주변해역 퇴적물 내의 중금속원소의 함량과 지화학적 존재형태)

  • Lee, Doo-Ho;Jeong, Yeon-Tae
    • Journal of Environmental Impact Assessment
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    • v.9 no.4
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    • pp.301-314
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    • 2000
  • Marine surface sediments in the vicinity of Samcheonpo coal-fired power plant were analyzed by a total analysis($HF+HNO_3+HClO_4$) and sequential extraction procedure for heavy metals in order to investigate the total concentrations and geochemical phases of heavy metals. The result showed that the concentrations of Cr, Cu, Fe and Zn were within ranges typical for coastal areas, which reflected the mineralogical composition of the sediments in the studied area. However, the distributions of Cd, Co, Mn, Ni and Pb were rather different from the former, indicating that these heavy metals had a different origin, or that they were affected by a different geochemical mechanism. Chemical partitioning of heavy metals using sequential extraction procedure revealed that Cu, Fe, Pb, Zn were significantly bound to the residual phases of the sediments, whereas carbonate phases contained considerable amounts of Mn. The significant association of Pb with the exchangeable fraction also indicated that Pb was more mobile and bioavailable than Cu, Fe, Mn, Zn.

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Determination of Heavy Metals Concentrations in Urban Air using ICP Method : in the Area of Chung-Ang University (ICP법에 의한 도시대기중 중금속 농도 측정: 중앙대학교를 중심으로)

  • 손동헌;신혜숙;정성윤;정원태
    • Journal of Korean Society for Atmospheric Environment
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    • v.9 no.3
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    • pp.222-229
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    • 1993
  • Total suspended particles in the atmosphere were collected on the quartz fiber filters using an ANdersen Hi-volume air sampler from March 1989 to October 1989 and from June 1990 to February 1991, at Chung-Ang University in Seoul. A total amount of eight heavy metals (Cr, Zn, Cd, Pb, Fe, V, Ti, Mn) in total suspended particles were determined by ICP spectrophotometer. The annual arithmetic mean concentration of total suspended particle was 162.3$\mug/m^3$ and eight metals(Cr, Zn, Cd, Pb, Fe, V, Ti, Mn) were 11.6, 609.2, 3.5, 337.1, 2739.5, 15.1, 89.4 and 100.5ng/$m^3$, respectively. The concentration of total suspended particle was highest in the spring(343.7$\mug/m^3$) and lowest in the summer(91.8$\mug/m^3$). These heavy metals were distinguished into two groups in terms of their particle size distribution. The contents of first-group heavy metals (Fe, Ti, Mn) were increased in accordance with the growth of the particle size. The contents of the second-group ones such as Pb, Cd, V, and Zn, on the contrary, came to increase according as the particle size reduced. Statistical analysis indicated that there was a correlation between total suspended particle and Fe in coarse particles, and between total Suspended Particle and Zn, Pb in fine particle.

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A study on the removal of mixed heavy metal ions using crab shell (게 껍질을 이용한 수중의 복합 중금속 제거에 관한 연구)

  • Kim, Dong-Seog
    • Journal of Environmental Science International
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    • v.11 no.7
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    • pp.729-735
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    • 2002
  • In order to examine the inhibition effect of other heavy metal ions on the removal of heavy metal ions by crab shell in aqueous solution, 10 heavy metal ions $(Cr^{3+},\;Cd^{2+},\;Ni^{2+},\;Zn^{2+},\;Hg^{2+},\;Cu^{2+},\;Mn^{2+],\;Fe^{2+},\;Fe^{3+},\;Pb^{2+})$ were used as single heavy metal ions and mixed heavy metal ions, respectively. In single heavy metal ions, $Pb^{2+},\;Cr^{3+},\;Cu^{2+}$ were well removed by crab shell, however, $Cd^{2+},\;Ni^{2+},\;Zn^{2+},\;Mn^{2+}$ were not. The heavy metal removal increased as the increase of covalent index (Xm$^2$r), and the relationship classified heavy metal ions as 2 heavy metal groups $(Fe^{3+},\;Fe^{2+},\;Cu^{2+},\; Cr^{3+},\;Mn^{2+},\;Ni^{2+},\;Zn^{2+}\;group\;and\;Pb^{2+},\;Hg^{2+},\;Cd^{2+}\;group)$. In mixed heavy metal ions, the removals of $Fe^{2+},\;Fe^{3+},\;Pb^{2+},\;Cu^{2+}$ as 0.49 m㏖/g, regardless of the existence of other heavy metal ions, were similar to the result of single heavy metal ions experiment. The removals of $Mn^{2+},\;Cd^{2+},\;Ni^{2+}$ decreased as the existence of other heavy metal ions, however, the removal of $Zn^{2+},\;Cr^{3+},\;Hg^{2+}$ increased.

The Study on Phase Transition Pressure of Donor doped Pb(Zr0.52Ti0.48)O3 Ceramics with Diamond Anvil Cell (다이아몬드 엔빌 셀을 이용한 Donor doped Pb(Zr0.52Ti0.48)O3 세라믹스의 상전이 압력 연구)

  • Cho, Kyung-Ho;Ko, Young-Ho;Seo, Chang-Eui;Kim, Kwang-Joo
    • Journal of the Korean Ceramic Society
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    • v.48 no.5
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    • pp.471-478
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    • 2011
  • Investigations of crystal structure and phase transition of $Pb(Zr_{0.52}Ti_{0.48})O_3$ ceramics doped with A-site substitution impurity (La, Nd) or B-site substitution impurity (Sb, Nb) at 2 mol% concentration were carried out. X-ray diffraction patterns of impurities doped $Pb(Zr_{0.52}Ti_{0.48})O_3$ ceramics have been measured at pressures up to ~5 GPa with diamond anvil cell and synchrotron radiation. The patterns were obtained at room temperature using methanol-ethanol mixture as pressure-transmitting media. In order to refine the crystal structure, Rietveld analysis has been performed. The structures of impurities doped $Pb(Zr_{0.52}Ti_{0.48})O_3$ ceramics are tetragonal in space group P4mm at ambient pressure and are transformed into a cubic phase in space group Pm$\bar{3}$m as the pressure increases. In this study, when A-site substitution donor $La^{3+}$ or $Nd^{3+}$ ion was added to $Pb(Zr_{0.52}Ti_{0.48})O_3$ ceramics, the phase transition phenomena showed up at the pressure of 2.5~4.6 GPa, but when B-site substitution donor $Nb^{5+}$ or $Sb^{5+}$ ion was added to it, the phase transition appeared at relatively lower pressure of 1.7~2.6 GPa.

Increased Peripheral NK Cell Fraction and Their Cytolytic activity in Patients with History of Recurrent Spontaneous Abortion (말초혈액 자연살해세포 분획 및 세포용해 활성도 분석을 통한 습관성 유산 위험군의 진단적 유용성에 관한 연구)

  • Choi, Ji-Young;Hwang, Su-Jin;Han, Ae-Ra;Yoo, Ji-Hee;Park, Dong-Wook;Park, Chan-Woo;Kim, Hye-Ok;Cha, Sun-Hwa;Kim, Jin-Young;Song, In-Ok;Koong, Mi-Kyoung;Kang, In-Soo;Yang, Kwang-Moon
    • Clinical and Experimental Reproductive Medicine
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    • v.37 no.2
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    • pp.115-124
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    • 2010
  • Objective: To testify whether the increased peripheral blood natural killer (pbNK) cells fraction and their cytolytic activity could coincide with patient's history of recurrent spontaneous abortion (RSA) and to evaluate these factors are can be valuable diagnostic markers in RSA. Methods: Women with a history of RSA comprised the patient group (n=35). Normal fertile women, who were experienced at least one healthy term birth without history of infertility or recurrent miscarriage, were included as the healthy control group (n=15). The pbNK cells of $CD3^-/CD56^+/CD16^+$ and their cytolytic activities against K562 cells were measured by flow cytometry and the values were compared between study and control groups. Results: Proportions of pbNK cells among peripheral blood monocytes (PBMC) ($14.2{\pm}5.2$ vs. $9.4{\pm}3.7%$, p=0.002, 95% confidence interval [CI], 1.8 to 7.8) was significantly higher in the patient group. The odds ratio of having RSA history was increased as 8.4 folds (59% of sensitivity, 80% of specificity, and 95% CI: 2.0 to 35.8) in patients who showed pbNK cells fraction above 12.1% which was determined as cut-off value by using ROC curve analysis. The cytolytic activities of pbNK cells which measured by three different ratio of effecter pbNK cells to target K562 cells and calculated by the percent of cytolytic K562 cells, were significantly higher in study group than that of control group (in 50:1 ratio, $48.3{\pm}19.0$ vs. $31.3{\pm}11.9%$, p=0.002; in 25:1 ratio, $37.0{\pm}18.1$ vs. $20.2{\pm}9.2%$, p<0.001; in 12.5:1 ratio, $23.5{\pm}12.7$ vs. $12.4{\pm}7.3%$, p=0.001). With the cut-off values of cytolytic activity of pbNK cells as 43.1% (50:1), 26.9% (25:1), and 17.4% (12.5:1) each, the risk of having RSA history was increased by 10.0, 11.4, and 15.0 folds in patients who had increased in each effector of pbNK to target of K562 cells ratio. Conclusion: The analysis of pbNK cells fraction and their cytolytic activity can be valuable diagnostic markers for RSA. We are going to planning the large scaled studies which include the data of obstetric outcomes in subsequent pregnancies to clarify our results of this study.

The Influence of Brand Type on Consumer Attitude Formation of Private Apparel Brand -A Comparison between Discount Store PB and Home-shopping Premium PB- (상표유형이 유통업체 의류상표에 더한 소비자 태도에 미치는 영향 -할인점 점포상표와 홈쇼핑 프리미엄상표의 비교-)

  • Choi, Mi-Young;Rhee, Eun-Young
    • Journal of the Korean Society of Clothing and Textiles
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    • v.30 no.9_10 s.157
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    • pp.1400-1412
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    • 2006
  • As PB market segments into premium market, PBs were drawing attentions in terms of creating profits as well as a means to differentiate building up store identity. The purpose of this study makes a comparative study on the difference of consumer attitude formation process in discount store and home-shopping distribution channel which are recently on the upswing. This paper investigated the consumer's attitude formation on the private apparel brand. Subjects of this study were consumers in their $20s{\sim}40s$ who are main customer groups of PBs. The data were analyzed by Structural Equation Modeling and Multi-Group Analysis of Amos 5.0 to verify the difference of the path between store PB and premium PB. Following are the results of the study. Consumer attitude formation path on PB grades showed statistically noticeable difference. In discount store PB, store evaluation didn't directly influence on consumer attitude formation but showed indirect effect. On the other hand, in home shopping premium PB case, product evaluation directly influenced on consumer attitudes with store evaluation. Hedonic attitude dimension connected with behavioral attitude(purchase intention) revealed difference in path. Also consumer's evaluation on variables in model turned out to be different according to brand grade.