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Geraldo Capannesi Alberto Rosada Maurizio Manigrasso Pasquale Avino 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(1):163-168
In geochemistry, the distribution of the Rare Earth Elements (REEs) in earth crust and mantle allows to understand geochemical
cycles and origin and age of igneous rocks. In this article REEs (Ce, Dy, Eu, La, Nd, Sm, Tb, and Yb), Th and U in ores of
the North-Latium (Bracciano area, Ceriti Mt., Fate Mt., Sabatini Mt., Vulsini Mt., Acqua Rossa basin), have been investigated
for evaluating the extraction feasibility for industrial applications. 107 samples were irradiated in the rotating rack of
the TRIGA Mark II reactor of the R.C. Casaccia (ENEA) at neutron flux of 2.6 × 1012
n × cm−2 × s−1 for 12 h together with primary and secondary standards. The gamma spectrometry measurements were performed after 8 h, 3 and
30 days of decay by means of HPGe detector (FWHM 1.75 keV at 1332.5 keV, peak/Compton ratio 55.1, relative efficiency of 22%)
connected to a multi-channel analyzer. The total REE mean content is 105 μg g−1, ranging widely between 2.23 and 410.5 μg g−1 (average coefficient of variation 112%). A similar behavior is found for Th and U: their average levels are 13.5 and 6.0 μg g−1, respectively. A quite good correlation between REEs and Th (and U) is found for Ceriti Mt. (r
2 > 0.8) whereas for the other areas the correlation is <0.7. The results obtained evidence the low U content in the investigated
locations. 相似文献
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This research, that is a framework of a big project regarding the knowledge of human metabolism in patients affected by renal disease, is aimed to assess the levels of some selected essential (Co, Fe, K, Na, Rb, Se and Zn) and non-essential elements (Br Cr, Cs, Hg, Ni and Sb) in different biological matrices such as whole blood, serum and urine, of three Italian sub-populations.The analytical methodology involved is the Instrumental Neutron Activation Analysis (INAA), a primary analytical technique: the samples (totally 144) were irradiated in the Triga nuclear reactor at the R.C.-Casaccia ENEA for 12 h at a neutron flux of 2.6 × 1012 n × cm− 2 × s− 1.The results show a similar distribution for essential elements whereas quite different for non-essential elements. The statistical treatment has evidenced no differences among the samples grouping the subpopulations into unique one. In this way, the levels found can be considered “reference values” in the investigated matrices. 相似文献
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Avino Pasquale Rosada Alberto Manigrasso Maurizio 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(2):423-430
Journal of Radioanalytical and Nuclear Chemistry - Nowadays, e-cigarettes are largely used, they are considered less dangerous than the traditional cigarettes. Actually, there are a lot of... 相似文献
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Pasquale Avino Geraldo Capannesi Alberto Rosada Maurizio Manigrasso Enrico Sabbioni 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(3):1957-1968
This research is a framework of a big project aimed to the knowledge of human metabolism in hemodialysis patients. For reaching high sensitivity and obtaining accurate values for elements at very low concentrations Instrumental neutron activation analysis (INAA) was used for its characteristics to be a primary analytical method and because it does not require any chemical–physical pretreatment. The samples analyzed (160) are representative of groups of homogeneous population and specific matrices (hemodialysis fluids and whole human blood). The irradiation was performed in the rotating rack (Lazy Susan) of the Triga Mark II reactor of the R.C. Casaccia-ENEA at a neutron flux of 2.6 × 1012 n cm?2 s?1 with an irradiation time of 12 h. The results on the hemodialysis fluids report the values and the behavior of selected trace elements: the levels of Br and Na show a decrease between the pre- and post-dialysis whereas Fe, K and Zn an increase. The other elements such as Cs, Rb and Se seem to keep constant between the two phases. Similar data are found for the whole human blood for the same selected elements. Finally, exploiting the INAA peculiarity it has been investigated the levels of trace and ultra-trace elements interesting from a toxicological (Hg, Ni, Sb) and nutritional (Co, Cr) point of view and seldom determined due to their analytical implications. Finally, a chemiometric investigation performed through dendrogram trees, Canonical discriminant analysis and principal component analysis, has evidenced the similar effects of the HF, HDF and BIC-treatments on the investigated fluids respect to the CAPD dialysis. 相似文献
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Pasquale?AvinoEmail author Geraldo?Capannesi Maurizio?Manigrasso Alberto?Rosada Mario?Vincenzo?Russo 《Chemistry Central journal》2013,7(1):173
Background
Anthropogenic activities introduce materials increasing levels of many dangerous substances for the environmental quality and being hazardous to human health. Major attention has been given to those elements able to alter the environment and endanger human health.The airborne particulate matter pollutant is considered one of the most difficult task in environmental chemistry for its complex composition and implications complicating notably the behavior comprehension. So, for investigating deeply the elemental composition we used two nuclear techniques, Neutron Activation Analysis and Photon Activation Analysis, characterized by high sensitivity, precision and accuracy. An important task has been devoted to the investigation of Quality Control (QC) and Quality Assurance (QA) of the methodology used in this study.This study was therefore extended as far back as possible in time (from 1965 until 2000) in order to analyze the trend of airborne concentration of pollutant elements in connection with the industrial and lifestyle growth during the entire period.Results
Almost all the elements may be attributed to long-range transport phenomena from other natural and/or anthropogenic sources: this behavior is common to all the periods studied even if a very light decreasing trend can be evidenced from 1970 to 2002. Finally, in order to investigate a retrospective study of elements in PM10 and their evolution in relationship with the natural or anthropogenic origins, we have investigated the Enrichment Factors. The study shows the EF trends for some elements in PM10 during four decades.Conclusions
The two nuclear techniques have allowed to reach elevated sensibility/accuracy levels for determining elements at very low concentrations (trace and ultra-trace levels). The element concentrations determined in this study do not basically show a significant level of attention from a toxicological point of view.8.
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