• 제목/요약/키워드: Basic Metals

검색결과 276건 처리시간 0.028초

컴퓨터 시뮬레이션을 통한 수평 인입 크레인 구성 재료의 잔존수명 예측 (Remaining Life Estimation of a Level Luffing Crane Component by Computer Simulation)

  • 김상열;김성수;최희규
    • 대한금속재료학회지
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    • 제48권6호
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    • pp.489-497
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    • 2010
  • The remaining life estimation of the level luffing crane component, which has operated for about 20 years is examined carefully, especially on the crane structures. To analyse the crane sructures, the basic load and load combination needed to be considered. We modeled various parts of the level luffing crane to analyse fatigue. Fatigue analysis results showed that the level luffing crane is in the fatigue life so that the crane is in the safe state in fatigue cumulative damage. Analysis results show that the remaining life of a jib upper beam would be about 10 years therefore, the level luffing crane should be stable for fatigue for that period.

유통식육에서 중금속 함량조사 (Determination of heavy metal contents in meats)

  • 최윤화;김연주;이경혜;강영일;이정학
    • 한국동물위생학회지
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    • 제33권3호
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    • pp.299-302
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    • 2010
  • This study was conducted to determine the content of heavy metals in meats available on the Korean markets. Trace metals (Pb, As and Cd) were detected in 4 kinds, 172 samples by inductively coupled plasma-mass spectrometry (ICP-MS). The values of heavy metals in meats were as follows; In beef, mean (minimum~maximum) values of the heavy metals were Pb: 0.075 (0.020~0.190)mg/kg, As: 0.010 (0.001~0.050)mg/kg and Cd: 0.43(0.07~2.11)${\mu}g/kg$. In pork, mean (minimum~maximum) values of the heavy metals were Pb: 0.065 (0.012~0.171)mg/kg, As: 0.004 (ND~0.021)mg/kg and Cd: 0.43(0.08~1.09)${\mu}g/kg$. In chiken, mean (minimum~maximum) values of the heavy metals were Pb: 0.060(0.016~0.211)mg/kg, As: 0.008 (ND~0.042)mg/kg and Cd: 0.42 (0.02~3.80)${\mu}g/kg$. In duck, mean (minimum~maximum) values of the heavy metals were Pb: 0.070 (0.011~0.157)mg/kg, As: 0.005 (0.001~0.011)mg/kg and Cd: 0.87 (0.15~3.75)${\mu}g/kg$. This results will be used as a basic data for the future legislation on the regulation and control of heavy metal in meats.

자원수급(資源需給)의 세계적(世界的)인 추세(趨勢)와 우리나라의 동향(動向) -국내자원(國內資源)의 유효이용(有效利用)을 위한 처리(處理) 및 회수기술(回收技術) 동향조사(動向調査)(1)- (Worldwide Trend and Korean Recent Status in the Supply-Demand for Resources -The Current Situation of Recycling Technology for Waste Resources in Korea(1)-)

  • 오재현;김미성;조성백
    • 자원리싸이클링
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    • 제15권3호
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    • pp.3-19
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    • 2006
  • 본 연구에서는 우리나라 미이용 자원의 유효이용 즉, 리싸이클링의 동향을 조사하기에 앞서 다양한 자원의 전체현황을 파악하려고 노력하였다. 그러기 위해서 자원수급의 세계적인 추세를 논하였고, 우리나라와 비교 검토하기 위해서 일본의 주요금속의 머티리얼 흐름을 조사하였다. 끝으로 우리나라 금속자원, 에너지자원 및 광물자원의 수급동향을 탐색, 고찰하였다.

달천광산 토양 내 중금속의 존재형태 및 오염도 (The Distribution Characteristics and Contamination of Heavy Metals in Soil from Dalcheon Mine)

  • 서지원;윤혜온;정찬호
    • 한국광물학회지
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    • 제21권1호
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    • pp.57-65
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    • 2008
  • 본 연구에서는 달천광산 토양 내 중금속의 함량을 알아보고 지화학적인 형태를 알아보고자 달천광산의 광미와 인근 저수지의 토양을 채취하여 화학분석법(전함량분석, 연속추출분석)을 적용하였다. 분석결과 달천광산 토양 내 중금속은 철 > 비소 >구리 > 납 > 크롬 순으로 높은 값을 보이며 특히 $63\;{\mu}m$ 이하의 토양에서 가장 높게 나타나 As, Cu, Pb 등 유해 중금속의 거동이 미립질 토양을 구성하는 광물과 연관되어 있음을 알려주었다. 연속추출 분석 결과, 인근 저수지 토양의 경우, $63\;{\mu}m$ 이하의 입도에저 철 > 납 > 구리 > 비소 > 크롬의 순으로 나타났다. 달천랑산 광미에서 측정된 비소는 양이온교환 형태로 존재하는 비율이 다른 형태에 비하여 가장 높은 값을 보이고 따라서 상대적으로 이동이 훨씬 용이한 것으로 추정된다. 광미와 인근 저수지의 토양 내 포함된 중금속의 전함량과 더불어 물리 화학적 결합상태에 따른 중금속의 존재형태를 규명하는 것은 중금속으로 오염된 토양을 복원하기 위한 기초 자료로 매우 중요하다. 더 나아가서 As와 Cr과 같은 독성 유해중금속의 화학종에 따른 유해성 평가를 위한 기초자료로 중요성이 있으며 지표수 및 지하수 환경오염의 정밀 연구를 위해 필수적이다.

Quantifying the Interactive Inhibitory Effect of Heavy Metals on the Growth and Phosphorus Removal of Pseudomonas taeanensis

  • Yoo, Jin;Kim, Deok-Hyun;Oh, Eun-Ji;Chung, Keun-Yook
    • 한국토양비료학회지
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    • 제51권1호
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    • pp.35-49
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    • 2018
  • This study was initiated to quantitatively evaluate the effects of five heavy metals (Cd, Cu, Zn, Pb, and Ni) on growth and P removal efficiencies of Pseudomonastaeanensis, known as the phosphorus accumulating microorganism. The heavy metals were added individually and with the binary mixture to the batch culturing system of Pseudomonastaeanensis. $IC_{50}$ and $EC_{50}$ were used to quantitatively evaluate their effects on the growth and phosphorus removal efficiency of Pseudomonas taeanensis in those treatments. Additionally, additive index value method was used to evaluate the interactive effects of heavy metals for Pseudomonas taeanensis in this study. As those heavy metals were singly added to Pseudomonastaeanensis, the greatest inhibitory effect on its growth and P removal efficiency was observed in Cd, whereas, the smallest effect was found in Ni. As the concentrations of all heavy metals added were gradually increased, its growth and P removal efficiency was correspondingly decreased. Specifically, $IC_{50}$ of Pseudomonas taeanensis for Cd, Cu, Zn, Pb, and Ni were $0.44mg\;L^{-1}$, $5.12mg\;L^{-1}$, $7.46mg\;L^{-1}$, $8.37mg\;L^{-1}$ and $14.56mg\;L^{-1}$, respectively. The P removal efficiency of Pseudomonas taeanensis was 81.1%. $EC_{50}$ values of Pseudomonas taeanensis for Cd, Cu, Zn, Pb, and Ni were $0.44mg\;L^{-1}$, $4.08mg\;L^{-1}$, $7.17mg\;L^{-1}$, $8.90mg\;L^{-1}$ and $11.26mg\;L^{-1}$, respectively. In the binary treatments of heavy metals, the lowest $IC_{50}$ and $EC_{50}$ were found in the Cd + Cu treatment, whereas, the highest $IC_{50}$ and $EC_{50}$ were found in the Zn + Pb and Pb + Ni treatments, respectively. Most of the interactive effects for the binary mixture treatments of heavy metals were antagonistic. Based on the results obtained from this study, it appears that they could provide the basic information about the toxic effects of the respective individual and binary treatments of heavy metals on the growth and P removal efficiency of other phosphorus accumulating organisms.

제올라이트와 제강슬래그에 의한 중금속과 영양염류 복합오염물질의 제거 효과 (Removal Efficiency of Heavy Metals and Nutrients by Zeolite and Basic Oxygen Furnace Slag)

  • 김용우;오명학;박준범;권오순
    • 한국지반환경공학회 논문집
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    • 제15권11호
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    • pp.13-19
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    • 2014
  • 투수성 반응벽체 공법은 지하수 오염을 정화하는 대표적인 방법 중의 하나이다. 영양염류와 중금속 등 여러 가지 오염물질이 동시에 존재하는 경우 두 가지 이상의 반응성 매질을 적용한 반응벽체공법으로 복합오염물질의 제거가 가능하다. 본 연구에서는 반응성 매질로 제올라이트와 제강슬래그를 함께 사용하는 경우 복합오염물질의 제거능을 평가하였다. 영양염류인 암모늄과 인산염, 중금속인 카드뮴이 혼합된 복합오염물질에 대하여 연속회분식실험을 통하여 제올라이트 및 제강슬래그와의 반응순서에 따른 오염물질 제거능을 분석하였다. 연속회분식실험 결과에 의하면 제올라이트-제강슬래그 순서로 반응하는 경우 영양염류와 중금속의 복합오염물질에 대한 제거능이 더 좋은 것으로 나타났다.

무기고화제를 이용한 중금속 오염 광미의 안정화 처리를 위한 기초연구 (A basic study for stabilization of heavy metal contaminated tailings by inorganic binders)

  • 민경원;김태풍;이현철;서의영
    • 산업기술연구
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    • 제29권A호
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    • pp.55-60
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    • 2009
  • Stabilization treatment is one of processes for wastes and their components to reduce their toxicity and migration rates to surroundings. Inorganic binders such as calcium hydroxide, blast furnace slag and red mud were tested for their potential applicability to in-situ stabilization of heavy metal contaminated tailings in the abandoned metal mines. Columns(150mm dia. ${\times}$ 450mm length) filled with mixtures of inorganic binders and tailing from the Geumjang mine with various mixing ratios of binders to tailings, 5%, 7% and 9% were applied artificial rainfall tests for 28 days. Effluents from columns filled with calcium hydroxide and tailing showed high pH's of ~12.5 and a increasing trend of concentration in Pb and Zn with a significant decrease in permeability in terms of elapsed days. Those with burning slag and tailing showed pH's of ~8.5 and significantly low concentrations in heavy metals with a stable permeability. In case of red mud, effluents showed significantly low concentrations in heavy metals but a decreased permeability with pH's of ~10.5. Conclusively, this basic study suggests burning furnace slag be a potential stabilizer for effective treatment of heavy metal contaminated mine tailings.

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현행 한국의 한약재 중금속기준개정 필요성 고찰 (Problems of Legal Permissible Limit in Metal Level of Herbal Drugs Using Current Korea)

  • 이선동;박경식
    • 대한예방한의학회지
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    • 제5권1호
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    • pp.31-40
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    • 2001
  • Legal permissible limit of herbal drugs metal level in Korea is define 'less 30.0ppm in total(except mineral drugs)' including Pb Hg Cd As Cr Ni etc. This limit has a lot of problems in several factors, that is, not divide hazard and essential elements, not consider high and low toxic effect in each metal, not calculate dose-response relationship and average health behavior in Korean etc. As a that result, It has strong limits and weakness in the basic toxicology and Oriental medicine. To improve and correct these factors, We need to several new approach as like below. It must be radical study following problems in short and middle-long period in the future, toxic metal and essential element must be divide to basic toxicology and also be diverse toxic effect. But mineral drugs that included a amount of severe toxic metals is being used as active prescription drug until now. If toxic, safety and side-effect of metals will be considered, mineral drugs must prohibit instantly or use at least after examined toxic effect. But one of the most important things about herbal drugs contamination, all people and department (government, farmer and trader, oriental medicine doctors and association) will be participate cooperative and collection for preventive or the least contamination in herbal drugs.

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