• 한국지하수토양환경학회지:지하수토양환경
• /
• 제23권5호
• /
• pp.37-44
• /
• 2018

Soil trace elements and their bioaccumulation in agricultural products have attracted widespread concerns, yet the crop uptake characteristics of trace elements in different soil-plants systems have been rarely investigated. Experiments were carried out to investigate the effect of soil properties on trace element concentrations in cabbage and radish. Soil pH and total organic matter were major factors influencing trace elements transfer from soil to vegetables. Inclusion of other soil properties in the stepwise regression analysis improved the regression models for predicting trace element concentrations. Consideration of other soil properties should be taken into account for more precise prediction of trace element concentrations in the two vegetables, which could help quantitatively evaluate the ecologic risk of toxic trace elements accumulation in crops.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2007년도 춘계학술대회 논문집
• /
• pp.1533-1539
• /
• 2007

It is mainly due to the toxic gases, produced from the material combustion, threatens human body in case of urban railway car like subway which passes through underground tunnel. In the field of railway industry, fire accidents was not frequent but occurs in each country and, the causes was investigated. The advanced country established the test standard (e.g., BS, EN) to measure the toxic gases quantitatively and, have applied to enhance the fire safety of railway car. We must also follow the procedures to use gangway material for railway car as stated the Safety regulation for the urban railway car. In this study, various gangway materials(silicon, synthtic rubber, soaltapulin) are used to investigate element of toxic gases when the fire occurs. The amount of toxic gases measured from the ISO 5659 chamber using cone heater was measured and compared the results for each materials.

• 한국산학기술학회논문지
• /
• 제18권11호
• /
• pp.778-784
• /
• 2017

참굴(Crassostrea gigas)의 패각운동을 이용하여 Alexandrium 속의 조기 출현모니터링 가능성을 고찰하였다. 지구규모에서 패류독화를 발생시키는 A. fundyense와 잠재적 유독종으로 알려진 A. affine를 이용하여 홀 소자센서(Hall element sensor)를 사용하여 참굴의 패각운동(SVMs)을 측정하였다. 참굴은 Isocrysis galbana를 먹이생물로 하여 안정화 시킨 다음 3일간 절식 시킨 후 실험에 제공하였다. 결과 참굴은 A. fundyense에 대해 세포밀도 20 cells/mL에서 SVMs 횟수가 $10.5{\pm}1.2times/hr$로 증가하여 민감하게 반응하였고, 세포밀도 500 cells/mL에서 재차 $14.1{\pm}5.7times/h$, 5,000 cells/mL에서 $27.9{\pm}11.1times/hr$로 SVMs가 급격한 증가를 보였다. 그러나 A. affine에 대해서는 세포밀도가 300 cells/mL까지 $6.7{\pm}3.9times/hr$로 기준 SVMs와 유사하였고, 세포밀도 1,000 cells/mL 이상에서 $15.3{\pm}10.8times/hr$로 급격히 증가하였다. 즉 A. fundyense는 20 cells/mL에서부터 참굴의 SVMs가 민감하게 반응하였지만, A. affine는 높은 1,000 cells/mL의 세포밀도에서 SVMs가 반응하였다. 이러한 결과에서 유독와편모조에 대한 참굴의 SVMs는 종에 따른 차이가 있어, A. fundyense의 초기발생 예보에는 유용하게 활용 가능하지만, A. affine에 응용하는 것은 어렵다는 결론을 얻었다.

• 자원환경지질
• /
• 제33권4호
• /
• pp.273-282
• /
• 2000

In order to investigate the extent and degree of arsenic and heavy metal contamination and the bioavailability of toxic elements around the abandoned mine in Korea, an environmental geochemical survey was undertaken in the Daduk mine. After appropriate preparation, tailings, soil, stream sediment, crop plant and fingernail samples were analysed for As, Cd, Cu, Pb and Zn by ICP-AES and ICP-MS. Elevated levels of 8,782 mg/kg As, 8.3 mg/kg Cd, 489 mg/kg Cu, 3,638 mg/kg Pb and 919 mg/kg Zn were found in tailings from the Daduk mine. These significant concentrations can impact on soils and sediments around the tailing ponds. Mean concentrations of As, Cd, Pb, Cu and Zn in soils are significantly higher than those in world average soil, especially for As and Pb. Element concentrations in sediments decrease with distance from the tailing ponds due to a dilution effect by the mixing of uncontaminated sediments. Arsenic and Cd are elevated in rice grains and stalks, and Cu and Zn concentrations in chinese cabbage, sesame and bean leaves are higher than the upper limit values for normal plant. Arsenic concentration in fingernails of farmers are higher than the normal level with a maximum value of 1.5 mg/kg. The post-ingestion bioavailability of toxic heavy metals in some paddy and farmland soils has been also investigated using the SBET (simple bioavailability extract test) method. The method utilises synthetic leaching fluids closelyanalogous to those of the human stomach. The quantities of As, Cd, Cu, Pb and Zn extracted from paddy soils after 1 hour indicated 15.9, 65.4, 46.2, 39.4 and 29.4% bioavailability, respectively and for farmland soils, 12.4, 26.0, 31.2, 29.3 and 19.4% bioavailability, respectively. The results of the SBET indicate that regular ingestion of soils by the local population could pose a potential health threat due to long-term toxic element exposure.

• 대한예방한의학회지
• /
• 제5권1호
• /
• pp.31-40
• /
• 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.

• 자원환경지질
• /
• 제31권2호
• /
• pp.111-125
• /
• 1998

Dispersion, migration and enrichment of environmental toxic elements from the Samkwang Au-Ag mine area were investigated based upon major, minor and rare earth element geochemistry. The Samkwang mine area composed mainly of Precambrian granitic gneiss. The mine had been mined for gold and silver, but closed in 1996. According to the X-ray powder diffraction, mineral composition of stream sediments and soils were partly variable mineralogy, which are composed of quartz, orthoclase, plagioclase, amphibole, muscovite, biotite and chlorite, respectively. Major element variations of the host granitic gneiss, stream sediments and soils of mining and non-mining drainage, indicate that those compositions are decrese $Al_2O_3$, $Fe_2O_3$, MgO, $TiO_2$, $P_2O_5$ and LOI with increasing $SiO_2$ respectively. Average compositional ranges (ppm) of minor and/or environmental toxic elements within those samples are revealed as As=<2-4500, Cd=<1-24, Cu=6-117, Sb=1-29, Pb=17-1377 and Zn=32-938, which are extremely high concentrations of sediments from the mining drainage (As=2006, Cd=l1, Cu=71, Pb=587 and Zn=481 ppm, respectively) than concentrations of the other samples and host granitic gneiss. Major elements (average enrichment index=6.53) in all samples are mostly enriched, excepting $SiO_2$, $Na_2O$ and $K_2O$, normalized by composition of host granitic gneiss. Rare earth element (average enrichment index=2.34) are enriched with the sediments from the mining drainage. Minor and/or environmental toxic elements within all samples on the basis of host rock were strongly enriched of all elements (especially As, Br, Cu, Pb and Zn), excepting Ba, Cr, Rb and Sr. Average enrichment index of trace elements in all samples is 15.55 (sediments of mining drainage=37.33). Potentially toxic elements (As, Cd, Cr, Cu, Ni, Pb, and Zn) of the samples revealed that average enrichment index is 46.10 (sediments of mining drainage=80.20, sediments of nonmining drainage=5.35, sediments of confluent drainage=20.22, subsurface soils of mining drainage=7.97 and subsurface soils of non-mining drainage=4.15). Sediments and soils of highly concentrated toxic elements are contained some pyrite, arsenopyrite, sphalerite, galena and goethite.

• 한국산업안전학회:학술대회논문집
• /
• 한국안전학회 1999년도 춘계 학술논문발표회 논문집
• /
• pp.271-276
• /
• 1999

미국을 비롯한 선진국들은 이미 휘발성 유기화합물(volatile organic compounds) 과 독성 중금속(toxic metals)을 비롯한 유해 대기오염물(hazardous air pollutants)에 대해 ATEOS (Airborne Toxic Element and Organic Species), TEAM(Total Exposure Assessment Measurement) 연구등의 대규모 연구를 통하여 인체에 미치는 영향이 가장 큰 물질군이 휘발성 유기화합물임을 밝혀낸 바 있다. (중략)

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
• /
• 제53권5호
• /
• pp.338-343
• /
• 2004

In general, the insulation and protective sheaths on electrical conductors are made of combustible substances like PVC, natural or synthetic rubbers, and other organic or synthetic materials. When an electrical fire starts due to overheating of conductors/joints or sparking/arcing, the first thing to ignite is usually the insulation on the cables. When the insulation bums, the produced fumes are very toxic. To solve the problem, we have surely need the fire resistance cable that doesn't bum in a high temperature and emit toxic fume for operating a disaster prevention installation. In this paper, we have simulated the thermal analysis for the fire resistance cable according to the values of current in a overload and a short, and the values of outside flame with the fire resistance cable of the L's company product(600 V, FR-8 : Four Core) using the finite element method(Flux2D).

• Journal of the Korean Wood Science and Technology
• /
• 제13권2호
• /
• pp.35-44
• /
• 1985

The purposes of this study were, first, to investigate retention levels of toxic elements and oxide individual plies for each panel and, second, to examine disproportioning of individual toxic elements Thirty five water gum plywood panels were treated with a copper-chromium-arsenic preservative (CCA) by the soaking process as the treament time were applied. Such individual plies at a distance of 2.5cm, 7.5cm from the edge were assayed for CuO, $CrO_3$, and $As_2O_5$ on the basis of copper, chromium and arsenic content by Atomic Absorption Spectrophotometry. In these experiments, 12mm thickness plywood panels made of water gum, which were selling, were selected for the preservative treatment. Treating solutions were prepared for 10%, dilute solution of copper-chromium-arsenic preservative and then 1, 3, 6, 12 and 24 hours soaking trements in CCA preservative were applied. The results obtained are as follows: 1. The retention of total oxide in the face and back plies (1+7) retained more than the retention of total oxide in the other plies. The total oxide retention for the individual plies except the face and back plies (1+7) was showed in the following orders; cross plies (3+5), cross plies (2+6), core ply (4). 2. The retentions of total oxide increased as the increase of treatment time. The CCA treated plywood retained high levels of total oxide retention in the face and back plies (1+7). 3. All the retentions in the face and back plies (1+7) is over 5Kg/$m^3$, New Zealand Timber Preservation Standards Specification, and after 6 hours, the retentions in the cross plies (3+5) is over 4. The relative penetration of copper, chromium, and arsenic were not affected by the treatment time. The proportion of arsenic decreased in relation to both copper and chromium and the proportion of copper increased in relation to both chromium and arsenic. 5. A disproportioning of copper, chromium occurred with longer distance from edge, and with longer distance from edge the leachability resistance of CCA treated specimens decreased. After 6 hours (soaking time), the proportion of active elements at a distance of 2.5cm from the edge was consistent. And after 24 hours-soaking, the proportion of active elements at a distance of 7.5cm from the edge was consistent.

• 분석과학
• /
• 제12권4호
• /
• pp.346-353
• /
• 1999

For the non-destructive multi-elemental analysis of environmental and biological materials, instrumental neutron activation analysis (INAA) was applied for the determination of toxic and trace elements in a set of three Algae samples provided by the International Atomic Energy Agency (IAEA). The analytical quality control was evaluated by comparing the analytical results of two standard reference materials of the National Institute of Standards and Technology (NIST); Oyster Tissue (SRM 1566a) and Citrus Leaves (SRM 1572). According to given analytical procedure, the concentration of 15-25 elements including spiked elements such as As, Cd, Cr and Hg in Algae samples were determined. To identify and validate these results, a data intercomparison program using more than 35 analytical methods in 150 laboratories was carried out and the estimated statistical data are summarized. Result of INAA is favorable, therefore, it is illustrated that can be applied for routine analysis of essential and toxic elements in algae samples as well as analytical quality assurance.