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551.
三江平原泥炭地微量元素垂直分布特征   总被引:2,自引:0,他引:2  
采用冬季采样,现场分层的方法,系统地研究了三江平原河床-河漫滩型泥炭地和谷底洼地型泥炭地微量营养元素和有益元素的垂直分布特征。结果表明,微量营养元素Cu、Zn、Fe、Mn、B和有益元素Ni、Sr、Ti、V、Co均有在G层急剧积累的趋势,Fe、Mn、B、Zn、Ti、Sr质量分数在Ase层明显高于泥炭层,某些微量元素间具有显著的相关性。  相似文献   
552.
Baseline concentrations together with biological variations of 29 trace elements (Ag, As, Au, Ba, Br, Cd, Ce, Co, Cr, Cs, Eu, Fe, Hf, I, Mn, Mo, Ni, Pb, Rb, Sb, Sc, Se, Sm, Sr, Tb, Th, Yb, Zn and Zr) were investigated in the brown alga, Sargassum filipendula collected from the western coast of Sri Lanka. Several elements (Co, Cr, Fe, Hf, Ni, Sc, Se, Th, Zr and the rare earth elements) were found to be enriched in S. filipendula compared to NIES No. 9 Sargasso reference material. Concentration of strontium in S. filipendula was highest at all sites. Chemical abundance of the rare earth elements decreased approximately linearly with increasing atomic numbers. The pattern of elemental distribution appears to be due to the fact that S. filipendula seems capable of concentrating high levels of trace elements under conditions of their very low availability in sea water. Concentration factors for elements in S. filipendula lie in a higher range compared with those reported in the literaure for brown algae.  相似文献   
553.
以研究成果资料为基础 ,探讨了环境地球化学与人体健康的关系 ,试图以医学与环境地球化学相结合和元素地球化学分布与生态学特征相结合的方式进一步阐述这一问题 ,揭示其内在联系和规律。最后从营养角度讨论了强身健体、延年益寿的方法  相似文献   
554.
Heterogeneous agglomeration (HA) is a very potential technology for coal-fired flue gas treatment.In this paper,the distribution and migration mechanisms of trace elements (TEs such as Se,As and Pb in CFPPs were studied on a 30,000 m3/hr pilot-scale experimental plat form.The influences of HA on the removal efficiency of gaseous and particulate TEs were well analyzed.The results showed that Se,As and Pb were enriched in fly ash,and their sen sitivity to particle size is quite differen...  相似文献   
555.
通过在一维煤粉燃烧炉上进行无烟煤添加高岭土吸附剂的燃烧实验,研究了无烟煤及其燃烧产物中18种环境有害微量元素的含量和分布;计算了高岭土在不同燃烧工况条件下对每种环境有害微量元素的吸附率.结果表明,高岭土对环境有害微量元素Cd, Pb, Sb, Sn, Ba, Co, Be, Cr, Ni, Mo, Tl, V, U, Mn, Th具有不同的吸附作用,吸附率为11.6%~500%;吸附效率与元素种类、燃烧工况等因素有关,环境有害微量元素Cd, Pb, Zn, Sb, Ba, Co, Be, Cr, Ni, Mo, Tl, V, U, Mn, Th的吸附能力,分级燃烧比不分级燃烧吸附效果更好,总吸附率差为8.4%~481%.  相似文献   
556.
激活甲烷菌的微量元素及其补充量的确定   总被引:35,自引:0,他引:35  
以血清瓶为间歇反应器 ,以醋酸钙、乙醇为基质 ,研究了厌氧消化过程中甲烷菌所需要的微量金属营养元素的种类和优化组合及它们的最佳补充投加量。研究结果表明 ,厌氧消化过程中微量元素对甲烷菌有激活作用 ,最佳微量元素组合为 Fe,Co,Ni,它们的最佳补充投加分别为 1.0 mg/ L· d,0 .1mg/ L· d,0 .2 mg/ L· d  相似文献   
557.
The content of As, Cd, Cr, Cu, Fe, Hg, Mg, Mn, Pb, and Zn was determined in Rosa damascena, Vitis vinifera, Crocus sativus, and Olea europaea L. herbal extracts produced in different areas in Greece. Samples were mineralized in a closed microwave system using nitric acid, and the concentration of all metals was determined by flame atomic absorption spectrometry. The herbal extracts contained As, Cd, Cr, Hg, Mn, and Pb at concentrations below their respective limits of detection, whereas Cu, Fe, Mg, and Zn were determined in varying quantities. The proposed method is precise and accurate, thus it can be used for the determination of metals in Rosa damascena, Vitis vinifera, Crocus sativus, and Olea europaea L. herbal extracts.  相似文献   
558.
Major and trace elements were determined in nzu (calabash clay) from Abia State, Nigeria, by atomic absorption spectrophotometry. Mean calcium content was 1900 ± 100 mg/kg dry weight, followed by Na 1400 ± 96, Fe 1500 ± 480, K 260 ± 150, and Mg 100 ± 48 mg/kg. The mean concentration of Zn was 35 ± 5, Cu 16 ± 2.0, Mn 17 ± 5.0, Cr 10 ± 1.0, Ni 9.0 ± 2.0, Cd 4.3 ± 1.7, Co 3.9 ± 1.1, and Pb 3.0 ± 0.8 mg/kg. The contents of Ba and V were <0.4 mg/kg. The mean Pb content was higher than the WHO safe limit (0.4 mg/kg) and EU (1 mg/kg) limit for food. Estimates of daily intake of Cd, Cr, Fe, and Ni upon consuming 30–80g of nzu were above the recommended daily intake values. The Ba, Ca, Co, K, Mg, Na, and Zn contents should not exceed the recommended daily intake while Cd, Ni, and Pb would pose health risks, especially in pregnancy. The total target hazard quotient indicated potential health risks to consumers.  相似文献   
559.
Mt. Sakurajima is a volcanic island in Japan, and a big city, Kagoshima, is quite close to the active volcano. Samples of volcanic ash fall erupted from Mt. Sakurajima were collected at several locations in Kagoshima City and analyzed for Hg and other elements, including major (Mg, Al, Ca, and Fe) and trace elements (V, Cr, Mn, Co, Ni, Zn, As, and Pb). The concentrations of Hg varied from 6.3 to 124 ng g?1, with the amounts of ash varying from 13 to 1230 g m?2 month?1. The Hg concentrations tended to be higher when the monthly amounts of ash fall were lower; other elements did not show such a tendency.  相似文献   
560.
ABTT浊点萃取-分光光度法测定废水中的痕量镍*   总被引:1,自引:0,他引:1  
利用非离子表面活性剂Triton X-114在温度高于其浊点时形成相分离行为,建立了浊点萃取-分光光度法测定水溶液中痕量镍的新方法,探讨优化了以1-偶氮苯-3-噻唑-三氮烯(ABTT)为显色剂,Triton X-114浊点萃取富集痕量镍的实验条件。在最大吸收波长为λ=540 nm外,其表观摩尔吸光系数为8.064×105 L/(mol.cm),线性范围为0~0.35μg/mL,相关系数为0.9990。在优化的实验条件下,进行了痕量镍的分析,加标回收率为97.9%~102.1%,应用于水溶液中痕量镍的测定,结果令人满意。  相似文献   
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