• 제목/요약/키워드: Cadmium(Cd)

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곡류중(穀類中)의 미량원소(微量元素)에 관(關)한 연구(硏究) (Studies on Trace Elements in Cereals)

  • 홍영숙;신정래
    • Journal of Nutrition and Health
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    • 제8권1호
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    • pp.39-46
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    • 1975
  • This studies were designed to know the contents of trace element and magnesium in cereals. Twenty two kinds of cereal, 104'samples, were analyzed by atomic absorption spectrophotometer for the determination of Manganese, Iron, Magnesium, Chrome, Cupper, Nickel, Zinc, Stannous, Lead and Cadmium. The results are as follows: 1) The contents of Mn and Fe in the sesame group show highest value and next is bean group. In the rice group its content shows lowest value than other cereals. 2) In the Cr content its value is lower than other elements in cereals respectively. Cr content of sesame and bean group show higher than rice and barley group. 3) The contents of Cu and Ni in the sesame and bean group show higher value than the value of rice and barley group. Its contents of rice and barley group is almost equal in Cu and Ni. 4) For the Zn content the value of sesame group is higher than other cereals and next is bean group. In the Sn content the value of bean group shows higher one than other cereals. The contents of Zn and Sn in rice and barley group are lower than other cereals. 5) The value of Pb is almost equal to each cereal. The content of Cd in bear group and barley group show higher than other cereals and its value of rice group is equal to the value of barley group.

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암모니움 이온을 가진 카드뮴 호스트 착물의 방향족 게스트 분자에 대한 포접선택성 변화 (Variation of Inclusion Selectivities of the Cadmium Host Complexes with Ammonium Oniums for Aromatic Guest Molecules)

  • 김종혁;이석근
    • 분석과학
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    • 제17권3호
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    • pp.282-288
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    • 2004
  • Inclusion selectivities of the cyanocadmate host complexes with ammonium oniums, $[Cd_x(CN)_{2x}][onium{\cdot}zG]$ (onium = $NMe_3Et^+$, $NMeEt{_3}^+$ and $NEt{_4}^+$, G = guest), have been investigated for $C_6H_6$ (B), PhMe (T), PhEt (E), ortho (O), meta (M), and para (P) isomers of $C_6H_4Me_2$ as the aromatic guest molecules. From the binary, ternary, quaternary and quinary mixed guests of B, T, E, O, M and P, the order of preference in the $NMe_3Et+$-host is $B{\gg}$T>P${\fallingdotseq}O{\fallingdotseq}M$ and E>O${\gg}P{\fallingdotseq}M$; in the $NMeEt{_3}^+$-host is T>B>P${\gg}O{\fallingdotseq}M$ and E>P${\gg}$M>O; in the $NEt{_4}^+$-host is $B{\gg}T{\fallingdotseq}O{\fallingdotseq}M{\fallingdotseq}P$. However, the $NEt{_4}^+$-host complexes of E, O, M and P mixed-guests were not obtained. These inclusion selectivities were compared to our previous results of the $NMe{_4}^+$-host; T>B>P${\gg}$M>O and E>P${\gg}$M>O.

서울시 대기 부유 분진중 중금속에 대한 발암 위해성 평가 (Carcinogenic risk assessment of heavy metals in suspended particulates of Seoul)

  • 신동천;정용;김종만;임영욱
    • 한국대기환경학회지
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    • 제10권2호
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    • pp.105-115
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    • 1994
  • This study was conducted to assess the health risk of carcinogenic heavy metals such as arsenic, nickel, chromium and cadmium Ambient concentrations of these metals were measured bimonthly, during May 1987 to March 1988. Respirable Particle concentrations of As, Ni, Cr, Cd in traffic area(Shinchon) were 16ng/㎥, 43ng/㎥, 4.2ng/㎥, 6.6ng/㎥, respectively, and in residential area(Bulkwang) were 25ng/㎥, 32ng/㎥, 4.7ng/㎥, 8.9ng/㎥, respectively. Carcinogenic risk of each metal was calculated by multiplication of ambient concentration and unit risk of the metal which was referred to recent version of Integrated Risk Information System(IRIS). Sum of the risk from these for metals was 9.8$\times$10$^{-5}$ as individual risk in traffic area and 13.9$\times$10$^{-5}$ in residential area.

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Struvite recovery from swine wastewater and its assessment as a fertilizer

  • Ryu, Hong-Duck;Lee, Sang-Ill
    • Environmental Engineering Research
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    • 제21권1호
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    • pp.29-35
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    • 2016
  • This study evaluated the fertilizing value of struvite deposit recovered from swine wastewater in cultivating lettuce. Struvite deposit was compared to complex fertilizer, organic fertilizer and compost to evaluate the fertilizing effect of struvite deposit. Laboratory pot test showed that the struvite deposit better enhanced lettuce growth in comparison to commercial fertilizers. It was revealed that the growth rate of lettuce was simultaneously controlled by phosphorus (P) and magnesium (Mg). Moreover, nutrients such as nitrogen (N), P, K, calcium (Ca) and magnesium (Mg) were abundantly observed in the vegetable tissue of struvite pot. Meanwhile, struvite application led to the lower accumulation of mercury (Hg), lead (Pb), chromium ($Cr^{6+}$) and nickel (Ni). In addition, no detection of cadmium (Cd), arsenic (As) and nickel (Ni) in the lettuce tissue was observed in struvite application pots. The experimental results proved that the optimum struvite dosage for lettuce cultivation was 0.5 g struvite/kg soil. The column experiments clearly showed that ammonia nitrogen was more slowly released from struvite deposit than from complex fertilizer. Consequently, it was concluded that the struvite deposits recovered from swine wastewater were effective as a multi-nutrient fertilizer for lettuce cultivation.

Assessment of Solubility, Heavy Metals and Microbial Safety in Differently- Treated Muscle Tissues of Mackerel Scomber japonicus

  • Asaduzzaman, A.K.M.;Lee, Won-Kyoung;Chun, Byung-Soo
    • Fisheries and Aquatic Sciences
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    • 제17권1호
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    • pp.59-65
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    • 2014
  • We measured the reductions in size and solubility of mackerel muscle that was freeze-dried, deoiled by supercritical carbon dioxide (SC-$CO_2$), or roasted. The percent size reduction and solubility were high in SC-$CO_2$-treated muscle compared with freeze-dried and roasted muscle. We used oil-free residues to test for heavy metals and determine microbial safety. The SC-$CO_2$, hexane, and ethanol were used to separate oil from muscle. The concentrations of cadmium (Cd) in all treated muscles were less than the values reported in the literature, as were the concentrations of lead in SC-$CO_2$- and hexane- treated muscle. In contrast, concentrations of arsenic and mercury in muscles were greater than the reported values regardless of treatment. Zinc and iron, which are beneficial for health, were found in high levels after all treatments of muscle tissue. After 6 months of storage at different temperatures, SC-$CO_2$-and ethanol-treated muscle showed few bacterial colonies, and none were found after 4 months of storage at $-20^{\circ}C$. These results will be useful to food-processing industries for maintaining high-quality, safe mackerel muscle.

생물고분자를 이용한 중금속 제거/회수에 관한 연구 (Removal/Recovery of Heavy Metals Using Biopolymer)

  • 안대희;정윤철
    • KSBB Journal
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    • 제8권4호
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    • pp.336-340
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    • 1993
  • 생물고분자 생산을 위하여 오니에서 slime을 생산하는 Zoogloea ramigera 115를 선택하였다. 추출한 생물고분자는 카드뮴, 아연 같은 금속에 대해서 높은 흡착성능을 나타냈다. 특히 발효조 broth는 높은 흡착성능을 나타냄으로써 부가적인 분리공정없이 생물흡착제로서 사용 가능할 것이다. 생물고분자는 calcium alginate bead 형태로 고정화되어 유가금속 회수를 위하여 충전층 반응기에 사용되었다. 생물흡착제는 구리, 카드뮴, 망간, 아연에 대하여 80% 또는 그이상의 높은 제거율을 나타냈으며 흡착-탈착-재흡착 실험에서 높은 안정성을 나타냈다. 고정화된 생물고분자 시스템은 이온교환수지와 같은 다른 중금속 제거 시스템과 경쟁력 및 잠재적인 산업상 응용 가능성을 보였다.

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풍원광산 지역의 토양 및 농작물 중금속 오염 (Heavy Metal Concentrations in Soils and Crops in the Poongwon Mine Area)

  • 김좌관
    • 한국지반환경공학회 논문집
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    • 제11권2호
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    • pp.5-11
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    • 2010
  • 폐광산 주변의 광미장, 폐석더미로 인해 주변 지역의 토양 및 농작물들은 중금속으로 오염 될 수 있다. 본 연구는 주변토양 용도별, 농작물 재배품목별, 광산과의 이격거리별로 분류하여 광산 주변 중금속 오염실태조사를 수행하였다. 갱구인근 지역에서 Zn와 Pb이 토양오염기준치를 초과하였으며 다른 지역에 비해 광미장 지역과 논 경작지 토양의 중금속농도가 비교적 높은 것으로 나타났다. 광산과의 이격거리에 따른 중금속 농도는 갱구에서 거리가 멀어질수록 점차 감소하였다. 토양과 쌀 시료의 중금속 상관관계는 As와 Cd이 상관관계성이 있는 것으로 나타났으나 다른 중금속들은 관계성이 없는 것으로 조사되었다.

Study on Characteristic difference of Semiconductor Radiation Detectors fabricated with a wet coating process

  • Choi, Chi-Won;Cho, Sung-Ho;Yun, Min-Suk;Kang, Sang-Sik;Park, Ji-Koon;Nam, Sang-Hee
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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    • pp.192-193
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    • 2006
  • The wet coating process could easily be made from large area film with printing paste mixed with semiconductor and binder material at room temperature. Semiconductor film fabricated about 25mm thickness was evaluated by field emissions-canning electron microscopy (FE-SEM). X-ray performance data such as dark current, sensitivity and signal to noise ratio (SNR) were evaluated. The $Hgl_2$ semiconductor was shown in much lower dark current than the others, but the best sensitivity. In this paper, reactivity and combination character of semiconductor and binder material that affect electrical and X-ray detection properties would prove out though experimental results.

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Neutronic design of pulsed neutron facility (PNF) for PGNAA studies of biological samples

  • Oh, Kyuhak
    • Nuclear Engineering and Technology
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    • 제54권1호
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    • pp.262-268
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    • 2022
  • This paper introduces a novel concept of the pulsed neutron facility (PNF) for maximizing the production of the thermal neutrons and its application to medical use based on prompt gamma neutron activation analysis (PGNAA) using Monte Carlo simulations. The PNF consists of a compact D-T neutron generator, a graphite pile, and a detection system using Cadmium telluride (CdTe) detector arrays. The configuration of fuel pins in the graphite monolith and the design and materials for the moderating layer were studied to optimize the thermal neutron yields. Biological samples - normal and cancerous breast tissues - including chlorine, a trace element, were used to investigate the sensitivity of the characteristic γ-rays by neutron-trace material interactions and the detector responses of multiple particles. Around 90 % of neutrons emitted from a deuterium-tritium (D-T) neutron generator thermalized as they passed through the graphite stockpile. The thermal neutrons captured the chlorines in the samples, then the characteristic γ-rays with specific energy levels of 6.12, 7.80 and 8.58 MeV were emitted. Since the concentration of chlorine in the cancerous tissue is twice that in the normal tissue, the count ratio of the characteristic g-rays of the cancerous tissue over the normal tissue is approximately 2.

Investigation of gamma radiation shielding properties of polyethylene glycol in the energy range from 8.67 to 23.19 keV

  • Akhdar, H.;Marashdeh, M.W.;AlAqeel, M.
    • Nuclear Engineering and Technology
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    • 제54권2호
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    • pp.701-708
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    • 2022
  • The mass attenuation coefficients (μm) of polyethylene glycol (PEG) of different molecular weights (1000-200,000) were measured using single-beam photon transmission. The X-ray fluorescent (XRF) photons from Zinc (Zn), Zirconium (Zr), Molybdenum (Mo), Silver (Ag) and Cadmium (Cd) targets were used to determine the attenuation of gamma radiation of energy range between 8.67 and 23.19 keV in PEG samples. The results were compared to theoretical values using XCOM and Monte Carlo simulation using Geant4 toolkit which was developed to validate the experiment at those certain energies. The mass attenuation coefficients were then used to compute the effective atomic numbers, electron density and half value layers for the studied samples. The outcomes showed good agreement between experimental and simulated results with those calculated theoretically by XCOM within 5% deviation. The PEG 1000 sample showed slightly higher μm value compared with the other samples. The dependence of the photon energy and PEG composition on the values of μm and HVL were investigated and discussed. In addition, the values of Zeff and Neff for all PEG samples behaved similarly in the given photon energy range, and they decreased as the photon energy increased.