• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.153-159
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• 2011

BACKGROUND: This experiment was conducted to investigate the distribution and burden characteristics of heavy metal in the rainwater sampled at Taean area, in the middle part of Korea, from April 2002 to October 2003. METHODS AND RESULTS: The relationship between concentration of heavy metal and other chemical properties in the rainwaters was also evaluated. Chemical properties in the rainwater were various differences with raining periods and years. It appeared that a weighted average pH values of rainwater was ranged from 5.0 to 5.1. Heavy metal concentrations in the rainwater were ranked as Pb > Zn > Cu > Ni > As > Cr > Cd. As compared with heavy metal concentrations of rainwater in 2002, Cu, Pb, and Zn were higher than other elements in 2003. There were positive correlation between major ionic components, such as ${NH_4}^+$, $Ca^{2+}$, $Mg^{2+}$, $K^+$, $Na^+$, ${SO_4}^{2-}$ and ${NO_3}^-$, and As, Cd, Zn, Cr, and Ni concentrations in rainwater. For heavy metal distribution of rainwater, the order of average enrichment factor was Cd > Pb > As > Cu > Zn > Ni > Cr, and these were relatively higher than the natural components such as Fe, Mg and Ca. The monthly enrichment factor were relatively high, from August to October at Taean. The monthly amount of heavy metal precipitation was high in the rainy season from July to August because of great influence of rainfall. CONCLUSION(s): The results of this study suggest that the heavy metals(Cd, Pb, As, Cu, and Zn) of rainwater is strongly influenced by anthropogenic sources rather than natural sources.

• Journal of Environmental Impact Assessment
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• v.32 no.5
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• pp.269-278
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• 2023

The pollution status of heavy metals in the soils of children's playground was investigated for a sustainable soil environment in urban parks of Seoul. As sampling sites, 281 locations were selected from a 7 districts in the Seoul city. The overall mean concentrations of the heavy metals (Cd 0.21 mg/kg, Cu 5.97 mg/kg, As 2.40 mg/kg, Pb 7.55 mg/kg, Zn 34.08 mg/kg, Ni 4.22 mg/kg, Hg 0.02 mg/kg and Cr6+ not detected.) in the soils of the palygrounds were lower than the worrisome level in criteria for area 1 in Korea soil environment conservation act. In addition, when the soil pollution grade (SPC) was evaluated as an average value, it was found to be less than 100, the first grade, at all points in the seven autonomous districts, indicating thatthe soil was in good soil condition. However, when evaluated as the maximum value, some of the five districts showed values of 100 or more. Therefore, it was found that continuous management and interest of the local government, which is the management body of children's playgrounds, is necessary for a safe soil environment.

• Journal of Animal Science and Technology
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• v.60 no.1
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• pp.29.1-29.6
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• 2018

Background: Dietary supplementation of zinc oxide (ZnO) to 2000 to 4000 mg/kg is known to be effective for the prevention and treatment of post-weaning diarrhea in the pig. Such a 'pharmacological' supplementation, however, can potentially result in environmental pollution of the heavy metal, because dietary ZnO is mostly excreted unabsorbed. Two experiments (Exp.) were performed in the present study to determine the effects of a lipid-coated ZnO supplement Shield Zn (SZ) compared with those of ZnO. Methods: In Exp. 1, a total of 240 21-day-old weanling pigs were fed a diet supplemented with 100 mg Zn/kg as ZnO (ZnO-100), ZnO-2500, SZ-100, or SZ-200 in 24 pens for 14 days on a farm with its post-weaning pigs exhibiting a low incidence of diarrhea. Exp. 2 was performed using 192 24-day-old piglets as in Exp. 1 on a different farm, which exhibited a high incidence of diarrhea. Results: In Exp. 1, fecal consistency (diarrhea) score (FCS) was less for the ZnO-2500 and SZ-200 groups than for the SZ-100 group (P < 0.05), with no difference between the SZ-100 and ZnO-100 groups. Both average daily gain (ADG) and gain:feed ratio were less for the SZ-200 group than for the ZnO-2500 group, with no difference between the ZnO-100 group and SZ-100 or SZ-200 group. The villus height (VH), crypt depth (CD), and VH:CD ratio of the intestinal mucosa were not influenced by the treatment. In Exp. 2, FCS was lowest for the ZnO-2500 group, with no difference among the other groups. However, neither the ADG nor gain:feed ratio was influenced by the treatment. Conclusion: Results suggest that physiological SZ supplementation has less beneficial effects than pharmacological ZnO for the alleviation of diarrhea irrespective of its severity and for promoting growth without influencing their integrity of the intestinal mucosal structures with little advantage over physiological ZnO in weanling pigs with a small pen size.

• Environmental Analysis Health and Toxicology
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• v.20 no.2 s.49
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• pp.179-186
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• 2005

Particulate materials (PM) less than 10 ${\mu}m$ in diameter are of special interest in air pollution because they are respirable and responsible for the increasing mortality rate of lung cancer and cardiovascular diseases. These particles are often referred to as $PM_{10}$ and they are divided into a coarse fraction and a fine fraction which is also often referred to as $PM_{25}$. In this study, we monitored the TSP, $PM_{10},\;PM_{2.5}$ concentration of ambient air collected in northern part of Seoul in early spring and measured the concentration of heavy metals; Cr, Mn, Zn, As, Cd, and Pb. All the heavy metals were found in the collected particles and the concentrations were variable in the $PM_{10},\;and\;PM_{2.5}$ respectively. The detected concentration ranges were Cr: $ND\~2,889ng/m^3,\;Mn:2.4\~257.9ng/m^3,\;Zn:ND\~353.7ng/m^3,\; As:ND\~22.3ng/m^3,\;Cd:0.1\~2.9ng/m^3,\;and\;Pb:ND\~392.2ng/m^3$ in fine particles. Heavy metal toxicity of the particles were also tested in $H_9C_2$ cell line derived from rat cardiomyocytes. As for the results of health risk assessment calculated by unit risk of IRIS, heavy metals in ambient air of Seoul metropolitan area were found to be responsible for the increase of total excess cancer risk. Among them, chromium (hexavalent) was found to be the most risky in fine particles of ambient air collected in the northern part of Seoul in early spring.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.3
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• pp.29-38
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• 2016

There have been only a few studies focused on the stabilization of metal (loid)s in anaerobic soils such as paddy soils. In this study, laboratory-scale column tests were conducted to artificially manipulate anoxic conditions in submerged paddy fields and we observed the release behavior of As, Cd, Pb, and Zn, as well as to examine the stabilization effect of steel refining slag (SRS) on the metal(loid)s. The leachate samples were collected and chemical parameters were monitored during the test period. Results suggest that anoxic conditions were developed during submersion, and that As or heavy metals (particularly Cd) fractions bound to ferrous (Fe) /manganese (Mn) oxides were easily dissociated. Moreover, As is also reduced by itself to a trivalent form with higher mobility in the reducing environment of rice paddy soil. However, it was also shown that SRS significantly decreased the dissolution of Zn, Pb, Cd, and As in the the leachates; their removal rates in the SRS-treated soil were 66 %, 45 %, 24 %, and 84 %, respectively, of those in the control soil.

• Journal of Animal Science and Technology
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• v.57 no.1
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• pp.4.1-4.5
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• 2015

The study was performed to investigate the effect of dietary supplementation of a lipid-encapsulated Zinc oxide on growth parameters and intestinal mucosal morphology piglets born to Duroc-sired Landrace ${\times}$ Yorkshire dams. Twenty-four 30-day-old piglets weaned at 25 days of age were orally challenged with $5{\times}10^8$ colony forming units of enterotoxigenic Escherichia coli (ETEC) K88 and fed one of the four diets for 7 days: (i) a nursery basal diet containing 100-ppm ZnO (referred to as BASAL), (ii) BASAL supplemented with 120-ppm apramycin (referred to as ANTIBIO), (iii) BASAL with 2,400-ppm ZnO (referred to as HIGH), and BASAL containing 100-ppm lipid-encapsulated ZnO (referred to as LE). All piglets were killed at the end of the experiment for histological examination on the intestine. The results showed that the average daily gain (ADG), the villus height: crypt depth (CD) ratio in the ileum, and the goblet cell density of the villus and crypt in the duodenum, jejunum, and colon were greater in the LE-fed group that those of the BASAL (p < 0.05). Fecal consistency score (FCS) and the CD ratio in the ileum were less in the LE-fed group, compared to the BASAL-fed one (p < 0.05). The effects observed in the LE-fed group were almost equal to those of the HIGH-fed group as well as even superior to those of the ANTIBIO-fed group. Taken together, our results imply that dietary supplementation of 100-ppm lipid-encapsulated ZnO is as effective as that of 2,400-ppm ZnO for promoting growth diarrhea and intestinal morphology caused by ETEC infection.

• Advances in nano research
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• v.12 no.5
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• pp.457-465
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• 2022

The potentials of Ni_xZn_1-xFe₂O₄ (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) nanoadsorbents were investigated for removal of Cd and Cr from contaminated water from an electroplating industry in Himachal Pradesh, India. Optimal values were recorded under batch adsorption experiments performed to remove dissolved heavy metal ions from industrial wastewater. The specific surface area (SSA) of nanoadsorbents perceived to vary in a range 35.75-45.29 cm²/g and was calculated from the XRD data. The influence of two operating parameters, contact time and dopant (Ni) concentration was also investigated at pH ~7 with optimum dosage. Kinetic studies were conducted within a time range of 2-10 min with rapid adsorption of cadmium and chromium ions onto Ni_0.2Zn_0.8Fe₂O₄ nanoadsorbents. Pseudo-second-order kinetic model was observed to be well fitted with the adsorption data that confirmed the only existence of chemisorption throughout the adsorption process. The maximum adsorption efficiency values observed for Cd and Cr were 51.4 mg/g and 40.12 mg/g, respectively for different compositions of prepared series of nanoadsorbents. The removal percentage of Cd and Cr was found to vary in a range of 47.7%-95.25% and 21%-50% respectively. The prepared series of nanoferrite found to be suitable enough for adsorption of both heavy metal ions.

• Journal of Surface Science and Engineering
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• v.15 no.4
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• pp.192-207
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• 1982

A study has been made of the interaction parameters of Zn other elements in dilute solutesd solution of molten cadmium alloys over the temperature range of 450 to 570$^{\circ}C$. The experi-mental measurementss were made in a touch instant cell using a fusedd Licl-KCl electrolyte. The activity of zinc in binary and ternary solutions sexhibiteds a strong positive deviation from Raoult's law. The addition of silver, indium or lead increased the activity of zinc whereas addition of copper, bismuth or tin decreased the zinc activity slightly. The results for all the metallic solutions showed a linear dependence of reciprocal of ab-solute temperature over the experimental range. The interaction parameters obtained are as follows.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.28-28
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• 1992

브라디키닌은 체내에서 강력한 혈관 확장 작용을 일으키는 autacoid(local hormone)로서 혈압의 항상성 유지, 모세혈관 투과성 증진, 염증 및 통증 반응 등에 관여하고 여러 장관 평활근을 수축시킨다. 또한 septic 혹은 endotoxic shock의 여러 원인 물질로도 생각되어진다. 최근 rhinovirus로 인한 감기의 제증상 원인 물질로도 브라디키닌이 주목을 받고있다. 이와같이 브라디키닌온 다양한 질병에 있어 중요한 원인 물질로 여겨지므로 브라디키닌 길항제들은 한두 질병의 치료제로 개발될 가능성이 높음이 강력히 제시되고 있는 실정이다. 이의 개발을 위해서 브라디키닌 수용체에 대한 연구는 필수적이라고 할 수 있다. 본 연구는 두 부분으로 나누어 진행중인데 첫째, 이제까지 보고된 브라디키닌 길항 물질들은 대부분이 브라디키닌의 특정 아미노산 잔기를 치환시킨 펩타이드 유도체로서 이들을 경구 투여시 peptidase어 의하여 쉽게 분해되고 또한 부분적인 효능제 활성을 갖는 불리한 점을 감안하여, 비펩타이드성 브라디키닌 길항제를 개발할 목적으로 한방 및 민간에서 자주 사용되어온 생약중에 브라디키닌 작용에 선택적 길항효과가 있는 물질을 검색한 바 활성을 보인 황금으로부터 작용 성분을 추적중에 있다. 둘째, 브라디키닌 수용체를 순수하게 분리 정제하기 위한 첫 단계로서 이 수용체의 결합시험(binding assay) 방법을 확립하고 더불어 여러 조직내(흰쥐의 여러 기관, 토끼 및 사람의 신장)의 브라디키닌 수용체의 분포를 파악하는 일이다. 횐쥐 조직의 실험 결과로부터 신장에 브라디키닌 수용체가 많이 분포함을 확인되었고 향후 토끼 신장으로부터 동수용체를 분리하고자 한다. 또한 토끼 신장의 근위세뇨관일차배양세포을 이용하여 브라디키닌의 신장에서의 작용기전도 살펴보고 있다.+}$, $Na^{+}$, NH$_{4}$$^{+}$ 및 H$^{+}$) 수용액 메디움에서의 Cd(II), Mg(II) 및 Zn(II)의 Dowex 1-X8, Cl$^{-}$ 수지에 대한 흡착은 역시 어떤 메디움에서도 Cd(II) 흡착이 제일 크며, 다음이 Zn(II) 이고 착이온을 형성않는 Mg(II)이 제일 작았다. 한편 메디움 종류별 D값의 크기순위는 H$^{+}$>K$^{+}$> $Na^{+}$>NH$_{4}$$^{+}$이였다. 메디움의 종류에 따라 D값의 차이가 나는 것은 금속이온의 착이온 형성과 금속이온의 용액내에서의 이온종의 상태와 관련이 있다고 생각된다. 마. MCl(M:K$^{+}$, $Na^{+}$, NH$_{4}$$^{+}$ 및 H$^{+}$)과 MNO$_{3}$ 용리액에 의한 Cd(II), Mg(II) 및 Zn(II)의 용리는 예상한 바와 같이 MCl에서 작은 Dv 값을 갖는데, 이것은 CdCl$_{4}$$^{2-}$ 착이온을 형성하거나 ZnCl$_{4}$$^{2-}$ , ZnCl$_{3}$$^{-}$같은 이온과 MgCl$^{+}$, MgCl$_{2}$같은 이온종을 형성하기 때문인것 같다. 한편 어떠한 용리액에서던지 NH$_{4}$$^{+}$의 경우

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.08a
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• pp.25-30
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• 2002

The ternary semiconducting compounds of the $A_{4}BX_{6}$(A=Cd, Zn, Hg; B=Si, Sn, Ge; X=S, Se, Te) type exhibit strong fluorescence and high photosensitivity in the visible and near infrared ranges, so these are supposed to be materials applicable to photoelectrical devices. These materials were synthesized and single crystals were first grown by Nitsche, who identified the crystal structure of the single crystals. In this paper. author describe the undoped and $Co^{2+}$-doped $Zn_{4}SnSe_{6}$ single crystals were grown by the chemical transport reaction(CTR) method using iodine of $6mg/cm^{3}$ as a transport agent. For the crystal. growth, the temperature gradient of the CTR furnace was kep at $700^{\circ}C$ for the source aone and at $820^{\circ}C$ for the growth zone for 7-days. It was found from the analysis of x-ray diffraction that undoped and $Co^{2+}$-doped $Zn_{4}SnSe_{6}$ compounds have a monoclinic structure. The optical absorption spectra obtained near the fundamental absorption edge showed that these compounds have a direct energy gaps. These temperature dependence of the optical energy gap were closely investigated over the temperature range 10[K]~300[K]