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DISTRIBUTION OF MERCURY, CADMIUM, COPPER, LEAD AND ZINC IN SEA WATER OF ULSAN BAY (울산만해수중의 수은, 카드뮴, 구리, 납, 아연의 농도분포)

  • WON Jong Hun;PARK Chung Kil;YANG Han Serb
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.9 no.3
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    • pp.177-184
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    • 1976
  • The concentrations of mercury, cadmium, copper, lead and zinc in sea water of Ulsan Bay were determined at spring and neap tide in August 1976. The range and mean of the heavy metal concentrations are as follows: at spring tide mercury 0.00-0.20ppb, 0.06ppb, cadmium 0.00-1.80ppb, 0,22ppb; copper 0.83-10.60ppb, 1.67ppb; lead 0.00-4.53ppb, 1.35ppb; zinc 0.0-21.8ppb, 4.4ppb, and at neap tide mercury 0.00-0.10ppb, 0.03ppb; cadmium 0.00-0.54ppb, 0.19ppb; copper 0.51-2.60ppb, 0.92ppb; lead 0.00-2.21ppb, 1.00 ppb; zinc 0.0-13.6ppb, 3.3ppb respectively. The concentrations and variations of the heavy metals were higher at spring tide than that at neap tide. The heavy metal levels of Ulsan Bay except Ulsan Harbour area was not higher than those of other coastal area. Low chlorosity, low pH and high heavy metal levels except zinc were determined in Ulsan Harbour at spring tide.

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Contactless Electroreflectance Spectroscopy of In0.5(Ga1-xAlx)0.5P/GaAs Double Heterostructures (In0.5(Ga1-xAlx)0.5P/GaAs 이중 이종접합 구조의 Contactless Electroreflectance에 관한 연구)

  • Kim, Jeong-Hwa;Jo, Hyun-Jun;Bae, In-Ho
    • Journal of the Korean Vacuum Society
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    • v.19 no.2
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    • pp.134-140
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    • 2010
  • We have investigated the contactless electroreflectance (CER) properties of $In_{0.5}(Ga_{1-x}Al_x)_{0.5}P$/GaAs double heterostructures grown by metal-organic chemical vapour deposition (MOCVD). The CER measurements on the sample were studied as a function of temperature, modulation voltage ($V_{ac}$), and dc bias voltage ($V_{bias}$). Five signals observed at room temperature are related to the GaAs, $In_{0.5}Ga_{0.5}P$, $In_{0.5}(Ga_{0.73}Al_{0.27})_{0.5}P$, $In_{0.5}(Ga_{0.5}Al_{0.5})_{0.5}P$, and $In_{0.5}(Ga_{0.2}Al_{0.8})_{0.5}P$ transitions, respectively. From the temperature dependence of CER spectrum, the Varshni coefficients and broadening parameters were determined and discussed. In addition, we found that the behavior of the CER amplitude for the reverse bias is larger than that of the forward.

Effect of SipJeonDaeBo-Decoction on Target Organ Metal Level in Rats (십전대보탕을 투여한 흰쥐의 중요장기중 금속농도변화에 대한 연구)

  • Yoon Seong-Wook;Lee Sun-Dong
    • Journal of Society of Preventive Korean Medicine
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    • v.4 no.1
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    • pp.51-69
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    • 2000
  • This dissertation was to research how some metal level within SipJeonDaeBo - Decoction, one of oriental prescriptions, influence Sprague-Dawley animals. 1. Under the experiment with drinking waters there was no metal ${\sim}0.65\;mg/L$ detected. A metal with feed found 0.001-376.983mg/kg. 2. In the mice's kidney, brain, bones used experiment, As searched 0.474 mg/kg, 0.486 mg/kg, 0.314 mg/kg 0.834 mg/kg respectively ; Cd 0.060 mg/kg, 0.045 mg/kg, 0.030 mg/kg, 0.353 mg/kg, ; Co 0.105 mg/kg, 0.063 mg/kg, 0.030 mg/kg, 0.399 mg/kg, ; Cr 0.292 mg/kg, 0.304 mg/kg, 0.234 mg/kg, 0.962 mg/kg, ; Cu 4.201 mg/kg, 3.759 mg/kg, 1.923 mg/kg, 0.484 mg/kg, ; Fe 57.535 mg/kg, 150.571 mg/kg, 17.178 mg/kg, 281.506 mg/kg, ; no Hg, Mn 0.612 mg/kg, 2.968 mg/kg, 0.528 mg/kg, 4.205 mg/kg, ; Ni 0.094 mg/kg, 0.072 mg/kg, 0.078 mg/kg, 27.714 mg/kg, ; Pb 0.269 mg/kg, 0.293 mg/kg, 0.283 mg/kg, 43.142 mg/kg ; Zn 4.149 mg/kg, 21.861 mg/kg, 8.088 mg/kg, 226.283 mg/kg respectively. 3. In level of hazardous metal within idney control group searched 0.194 {\pm}\; 0.052 mg/kg, experimental I g개up $0.189{\pm}0.036\;mg/kg$, experimental I group $0.264 {\pm}{\pm}\;0.179\;mg/kg$. In level of non hazardous metal control group searched $15.917{\pm}5.575\;mg/kg$, experiment I group $17.064{\pm}2.246\;mg/kg$, experiment II group $16.892{\pm}3.586\;mg/kg$. Besides in total level of metal control g.cup detected $6.484{\pm}2.258\;mg/kg$, experiment I group $6.940{\pm}0.914\;mg/kg$, experiment II group $6.915{\pm} 1.508\;mg/kg$ There all was no statistical significance. 4. In level of hazardous metal within the liver control group searched $0.187{\pm}0.048\;mg/kg$, experiment I g개up $0.168[\pm}0.079\;mg/kg$, experiment II group $0.277{\pm}0.159\;mg/kg$. In level of non hazardous heavy metal control group detected $44.925{\pm}18.468\;mg/kg$, experiment I group $39.917{\pm}12.772\;mg/kg$, experiment II group $49.525{\pm}33.484\;mg/kg$. Besides in total concentration control group searched $18.082{\pm}7.395\;mg/kg$, experiment I group $16.068{\pm}5.128\;mg/kg$, experiment II group $19.977{\pm}13.443\;mg/kg$. There was no statistical significance but hazardous metal gets more level in the experilnent group than in the control group. 5. In level of hazardous metal within brain control group searched $0.145{\pm}0.056\;mg/kg$, experiment I group $$0.167{\pm}0.030\;mg/kg, erperiment II group $0.172{\pm}0.123\;mg/kg$. In level of non hazardous heavy metal control group detected $6.488{\pm}0.965\;mg/kg$, experiment I group $7.290{\pm}0.588\;mg/kg$, experiment II group $7.010{\pm}1.627\;mg/kg$. Besides in total concentration control group searched $2.683{\pm}7.395\;mg/kg$, experiment I group $3.017{\pm}0.238\;mg/kg$, experiment II group $2.908 {\pm} 0.711\;mg/kg$. Therefore there was no statistical significance. 6. In level of hazardous metal within bone control group searched $8.172{\pm}5.195 \;mg/kg$, experiment I group $9.128{\pm}4.143\;mg/kg$, experiment II group $9.401{\pm}6.924\;mg/kg$. There is statistical significance(p<0.05). In level of non hazardous metal control group detected $94.065{\pm}36.035\;mg/kg$, experiment I group $147.563 {\pm}79.939\;mg/kg$, experiment II group $142.730{\pm}77.374\;mg/kg$. Besides in total level control group searched $48.530{\pm}16.523\;mg/kg$, experiment I group $64.502{\pm}31.078\;mg/kg$, experiment II group $62.733 {\pm}34.641\;mg/kg$. Therefore there was no statistical significance. 7 In the correlative research as to how each metal influences to ingestion Cd and Co searched 0.954 and Pb and Ni -0.0884 from kidney. Co and Cd was 0.995 and Zn and As -0.190 from liver. Co and Cd were 0.995 and Zn and Cu -0.393 from brain. Co and Cd were 0.998 and Zn and Mn -0.206 from bones

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Comparative Analysis of Quantitative Signal Intensity between 1.0 mol and 0.5 mol MR Contrast Agent (1.0 mol 과 0.5 mol MR조영제의 정량적 신호강도 비교분석)

  • Jeong, Hyun Keun;Jeong, Hyun Do;Nam, Ki Chang;Jang, Geun Yeong;Kim, Ho Chul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.12
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    • pp.134-141
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    • 2015
  • The purpose on this research is quantitatively comparing and analyzing signal intensity of 1.0mol and 0.5mol contrast agent. For this study, two MR phantoms were produced. One of them is used with 1.0mol Gadobutrol. The other is used with 0.5mol Gadoteridol. These two phantoms respectively have been scanned by SE T1 sequence which is used to get a general contrast-enhanced image in 1.5T MRI and 3D FLASH sequence which is used as enhanced angio MRI. Signal intensity was measured by scanned images as per contrast agent dilution ratio. The results were as follow: RSP(Reaction Starting Point) of the two sequences(2D SE, 3D FLASH) was respectively 6.0%, 60.0% in 0.5mol contrast and 2.0%, 20.0% in 1.0mol contrast, which means in 0.5mol contrast, RSP was formed faster than the one in 1.0mol contrast. MPSI was respectively 1358.8[a.u], 1573[a.u] in 0.5mol contrast and 1374[a.u], 1642.4[a.u] in 1.0mol contrast, which means 0.5mol contrast's MPP (0.4%, 10.0%) was formed faster than 1.0mol contrast's MPP (0.16%, 1.8%). Lastly, RA as per contrast agent dilution ratio was 27.4%, 11.8% wider in 0.5mol contrast(20747.4[a.u], 23204.6[a.u]) than in 1.0mol contrast(12691.9[a.u], 20747.4[a.u]). According to the study, we are able to assure that signal reaction time of 1.0mol contrast is slower than the one of 0.5mol contrast in contrast-enhanced MRI at two different sequences(2D SE, 3D FLASH). Furthermore, owing to the fact that there are not any signal intensity differences between 1.0mol and 0.5mol contrast, it is not true that high concentration gadolinium MR contrast agent does not always mean high signal intensity in MRI.

Effects of Gadolinium Contrast agent on Bone Mineral Density Measurement using Dual Energy X-ray Absorptiometry (가돌리늄조영제가 이중에너지 X-선 흡수법을 이용한 골밀도검사에 미치는 영향)

  • Lee, Keun-Ohk;Lee, Min-Su
    • Journal of the Korean Society of Radiology
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    • v.15 no.1
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    • pp.63-70
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    • 2021
  • Radiographic contrast agents are used for diagnostic purposes and are one of the factors affecting measured values in bone density tests. They are absorbed into tissues and have an effect of increasing the measured values of bone density, so they are avoided as much as possible before performing a bone density test. MRI contrast agents, which have different physical properties and mechanisms of action than radiographic contrast agents, are based on gadolinium, a metal element. They have radiopacity characteristics, so MRI are generally performed prior to examination using radiation. The purpose of this study was to investigate the effects of MRI contrast agents on bone mineral density examination using dual energy X-ray absorption. Two types of gadolinium based MRI contrast agents were injected into an acrylic water tank for each volume, and the humanoid spine phantom was inserted and the BMD and T-score from (L1-L4) were analyzed by scanning a total of 30 times, 5 times for each injection type. The average value of the measured total (L1-L4) bone density for each of the two contrast agents was 0.952±0.052, 0.957±0.050, and 0.956±0.05g/㎠, respectively, for the Gadoterate Meglumine component 0mL, 7.5mL and 15mL, when the gadobutrol components were 0mL, 5mL, and 10mL, there was no statistically significant difference at all sites at 0.953±0.001, 0.954±0.001, and 0.945±0.001g/㎠, respectively(p>0.05). The average value of total T-score was -0.46±0.05, -0.4±0, -0.42±0.04 when the Gadoterate Meglumine component was 0mL, 7.5mL and 15mL, respectively. When the Gadobutrol ingredients were 0mL, 5mL and 10mL, there was no statistically significant difference in all areas, with -0.46±0.05, -0.46±0.05, and 0.5±0.00, respectively. In this experiment, the MRI contrast agent was found to have no effect on bone density tests, using the dual-energy X-ray absorption method. There is a limitation in that physical conditions such as kidney and health conditions etc. were not taken into consideration, so further clinical research is expected to be conducted in the future.

Study on Characteristics of Sn-0.7wt%Cu-Xwt%Re Solder (Sn-0.7wt%Cu-Xwt%Re 솔더의 특성에 관한 연구)

  • Noh, Bo-In;Won, Sung-Ho;Jung, Seung-Boo
    • Journal of the Microelectronics and Packaging Society
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    • v.14 no.4
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    • pp.21-25
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    • 2007
  • In this study, the properties of Sn-0.7wt%Cu-Xwt%Re(X=$0.01{\sim}1.0$) older were investigated by using DSC(differential scanning calorimetry), wetting balance, victors hardness and tensile testers. The melting temperature of solder was increased with increasing the contents of rare earth element, and the melting temperature range of Sn-0.7Cu-($0.01{\sim}1.0$)Re solder was $233.9{\sim}234.7^{\circ}C$. The wettability with Sn-0.7Cu-0.1Re solder was higher than that of Sn-0.7Cu-0.01Re and Sn-0.7Cu-1.0Re solders, and the wettability of Sn-0.7Cu-0.1Re solder was higher than that of Sn-0.7wt%Cu-0.01w%P solder. Also, the hardness and tensile strength of solder were increased with increasing the contents of rare earth element.

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Effects of Phytezyme Supplementation on the Growth Performance and Nutrient Digestibility in Growing Pigs

  • Hong, J.W.;Kim, I.H.;Kwon, O.S.;Lee, S.H.;Bae, H.D.;Kang, S.J.;Yang, U.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.10
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    • pp.1440-1443
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    • 2001
  • Forty eight $Duroc{\times}Yorkshire{\times}Landrace$ pigs ($15.2{\pm}0.3kg$ average initial BW) were used conducted to evaluate the effects dietary phytase (Phytezyme, WOOJIN, Co. Ltd) supplementation on the growth performance and nutrient digestibility in growing pigs. There were three pigs per pen and four pens per treatment. Treatments were 1) Con (corn-wheat-SBM), 2) PE0.1 (low-P iet+0.1% Phytezyme), 3) PE0.2 (Iow-P diet+0.2% Phytezyme), 4) PE0.3 (low-P diet+0.3% Phytezyme). During d 0 to 28, average daily gain was not significantly different among the treatments. Pigs fed PE0.3 diet significantly decreased (p<0.05) their average daily feed intake compared to pigs fed Con diet. Also, gain/feed in pigs fed PE0.1 and PE0.3 diet was improved (p<0.05) compared to pigs fed Con and PE0.2 diet (p<0.05). For d 28 to 56, pigs fed PE0.2 diet grew significantly faster (p<0.05) than pigs fed Con and PE0.1 diet. Gain/feed was greater (p<0.05) for PE0.2 and PE0.3 treatments than for Con. For overall period, average daily gain was increased (P<0.05) by the addition of 0.2% Phytezyme compared with Con. Gain/feed was significantly improved (p<0.05) by supplementation of PE0.3. Pigs fed PE0.2 showed increased DM and N digestibilities compared to pigs fed other treatments. Supplemented diets PE0.2 and PE0.3 improved (p<0.05) the apparent digestibility of Ca and P compared to other treatments. In conclusion, the results obtained from these feeding trials suggest that the Phytezyme supplementation of diets for growing-finishing pigs had improved growth performance and nutrient availability.

The Critical Concentration and Flow Equation of Aqueous Carboxymethyl Chitin Solution (Carboxymethyl Chitin 수용액의 임계농도와 유동방정식)

  • PARK Seong-Min;LEE Keun-Tai;KIM Sang-Moo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.1
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    • pp.92-96
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    • 1996
  • To elucidate the flow properties of carboxymethyl chitin (CM-chitin), the critical concentration and flow equation of aqueous CM-chitin solution were investigated. The concentration of $0.8\%$ appeared to be the critical concentration. So interaction occurred between polymer chains in the CM-chitin solutions had the higher concentration than $0.8\%$ but not in lower than $0.8\%.\;0.5\%$ CM-chitin solution was revealed as a newtonian flow but $1.0\%$ CM-chitin solution showed a pseudoplastic flow. Flow constants of $3.0\%$ CH-chitin solution were 0.0908cp for $\eta_\infty$, 770cp for $\eta_0$, 0.81 for $\beta$ and 0.36 for n. Therefore, flow equation of $3.0\%$ CM-chitin solution was as follow; $$\eta=0.1+\{{770/(1+0.81D^{0.36})\}$$.

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Health-related Factors and Nutritional Status in Shift-workers at Coffee Shops - Focused on Single Women in Twenties in Seoul - (커피전문점 교대근로자의 건강관련요인과 영양상태 조사 - 서울지역 20대 미혼여성을 중심으로 -)

  • Lee, Seung-Lim;Kim, Soo-Jin
    • Korean Journal of Community Nutrition
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    • v.18 no.5
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    • pp.467-477
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    • 2013
  • This study examined the health-related factors and nutritional status of 89 single women workers in their 20's who work night and day shift at the take-out coffee shops and the 89 single women office workers. The results of the study are summarized as follows: The shift-workers showed lower rate of office tenure (p < 0.001), income (p < 0.001), job satisfaction (p < 0.05), weight (p < 0.05), and higher rate of weight change (p < 0.001) than the non shift-workers. The shift-workers showed lower rate of of exercise (p < 0.001), sleeping hours (p < 0.01), and good health condition (p < 0.01), and higher rates of smoking (p < 0.001), presence of disease (p < 0.001), gastric and intestinal illnesses (p < 0.001) than the non shift-workers. More than 88.8% of the shift workers answered that they ate alone (p < 0.001). The shift workers showed lower rate of regularity of meal (p < 0.001), balanced diet (p < 0.001), and mealtime (p < 0.001), and higher rate of skipping breakfast (p < 0.001), consumption of salty and spicy food (p < 0.001), and overeating (p < 0.01) than the non shift-workers. The shift workers consumed (p < 0.001) less frequently rice, soup and side dishes, and more frequently noodles and snack, bread than the non-shift-workers. The shift workers showed lower rate of consumption of beer (p < 0.01), and higher rate of consumption of coffee (p < 0.001), tea (p < 0.01) and soju (p < 0.001) in once a week or more intakes than the non-shift-workers. The shift workers showed higher rate of consumption of carbohydrates (p < 0.05), and calcium (p < 0.05) and lower rate of consumption of protein (p < 0.05), fiber (p < 0.05), vitamin C (p < 0.05), and folate (p < 0.05) intakes than the non-shift-workers.

Effects of A-site Vacancies on the Piezoelectric Properties of 0.97Bi0.5+x(Na0.78K0.22)0.5-3xTiO3-0.03LaFeO3 Lead-free Piezoelectric Ceramics (A-site Vacancy가 0.97Bi0.5+x(Na0.78K0.22)0.5-3xTiO3-0.03LaFeO3 무연압전 세라믹스의 압전특성에 미치는 영향)

  • Park, Jung Soo;Lee, Ku Tak;Cho, Jeong Ho;Jeong, Young Hun;Paik, Jong Hoo;Yun, Ji Sun
    • Journal of the Korean Ceramic Society
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    • v.51 no.6
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    • pp.527-532
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    • 2014
  • $0.97Bi_{0.5+x}(Na_{0.78}K_{0.22})_{0.5-3x}TiO_3-0.03LaFeO_3$ lead-free piezoelectric ceramics were fabricated by a solid state reaction method. $LaFeO_3$ additives were added to $Bi_{0.5}(Na_{0.78}K_{0.22})_{0.5}TiO_3$ for volatile compensation of bismuth and sodium ions in the sintering process. To create A-site vacancies, the mole ratio and charge valence of A-site ions ($Bi^{3+}$, $Na^+$ and $K^+$) were controlled. The improved piezoelectric properties were observed by addition of $LaFeO_3$ and control of A-site vacancies. In particular, a $d_{33}^*(S_{max}/E_{max})$ value of 614pm/V and an electric field induced strain of 0.33% was observed in $0.97Bi_{0.505}(Na_{0.78}K_{0.22})_{0.485}TiO_3-0.03LaFeO_3$ ceramic.