Comparison of trace elements in freshwater pearls cultured in Japan, China, and USA

2021 ◽  
pp. 1950018
Author(s):  
Ikuko Sakakura ◽  
Hidetsugu Tsuchida ◽  
Yoshitaka Sasaki ◽  
Misako Miwa

In this paper, we performed PIXE analysis of trace elements in freshwater pearls cultured in four different areas: Lake Biwa (Japan), Lake Kasumigaura (Japan), an unidentified lake in China, and Kentucky Lake (USA). We investigated the difference of trace elements contained in the four pearls from different aquaculture environments. The observed trace elements are Mn, Fe, Cu, Zn, and Sr. The major trace elements are Mn, Sr for all the samples. From comparison of the proportions of elements contained, we found the following features: (1) The Kasumigaura pearl has a nucleus with a high Mn/Sr ratio, (2) The Biwako pearl is low in iron content, and (3) The American pearl has high in Fe/Sr, Cu/Sr, and Zn/Sr ratios.

1983 ◽  
Vol 218 (1210) ◽  
pp. 119-126 ◽  

The number of iron atoms in the dimeric iron-containing superoxide dismutase from Pseudomonas ovalis and their atomic positions have been determined directly from anomalous scattering measurements on crystals of the native enzyme. To resolve the long-standing question of the total amount of iron per molecule for this class of dismutase, the occupancy of each site was refined against the measured Bijvoet differences. The enzyme is a symmetrical dimer with one iron site in each subunit. The iron position is 9 ņ from the intersubunit interface. The total iron content of the dimer is 1.2±0.2 moles per mole of protein. This is divided between the subunits in the ratio 0.65:0.55; the difference between them is probably not significant. Since each subunit contains, on average, slightly more than half an iron atom we conclude that the normal state of this enzyme is two iron atoms per dimer but that some of the metal is lost during purification of the protein. Although the crystals are obviously a mixture of holo- and apo-enzymes, the 2.9 Å electron density map is uniformly clean, even at the iron site. We conclude that the three-dimensional structures of the iron-bound enzyme and the apoenzyme are identical.


1996 ◽  
Vol 06 (01n02) ◽  
pp. 395-403
Author(s):  
Masae Yukawa ◽  
Yoshito Watanabe ◽  
Yoshikazu Nishimura ◽  
Mieko Kimura

PIXE technique was applied to measurement of trace elements in total diet samples collected in Japan for estimation of their daily dietary intake. Results of PIXE analysis were compared with INAA Concentration of Cl, K, Mn and Zn by PIXE analysis well agreed with the results from NAA, while Ca, Fe and Cu showed different results between these two techniques. Preliminary data of elemental concentrations in Mate-cha, a kind of tea popular in South America, determined by ICP-AES indicated a little higher concentration of Cu than that by PIXE and much lower value than that by INAA For Zn. concentrations by PIXE and ICP well agreed to each other, while INAA gave much lower value. Japanese internal radiation doses by 137 Cs and 90 Sr were estimated to be 2.30µSv/year and 1.27µSv/year respectively as the effective dose equivalents using the daily intake data obtained for K and Ca.


2017 ◽  
Author(s):  
Lennart J. de Nooijer ◽  
Anieke Brombacher ◽  
Antje Mewes ◽  
Gerald Langer ◽  
Gernot Nehrke ◽  
...  

Abstract. Barium (Ba) incorporated in the calcite of many foraminiferal species is proportional to the concentration of Ba in seawater. Since the open ocean concentration of Ba closely follows seawater alkalinity, foraminiferal Ba/Ca can be used to reconstruct the latter. Alternatively, Ba/Ca from foraminiferal shells can also be used to reconstruct salinity in coastal settings where seawater Ba concentration corresponds to salinity as rivers contain much more Ba than seawater. Incorporation of a number of minor and trace elements is known to vary (greatly) between foraminiferal species and application of element/Ca ratios thus requires the use of species-specific calibrations. Here we show that calcite Ba/Ca correlates positively and linearly with seawater Ba/Ca in cultured specimens of two species of benthic foraminifera, Heterostegina depressa and Amphistegina lessonii. The slopes of the regression, however, vary 2–3 fold between these two species (0.33 and 0.78, respectively). This difference in Ba-partitioning resembles the difference in partitioning of other elements (Mg, Sr, B, Li and Na) in these foraminiferal taxa. A general trend across element partitioning for different species is described, which may help developing new applications of trace elements in foraminiferal calcite in reconstructing past seawater chemistry.


1996 ◽  
Vol 06 (01n02) ◽  
pp. 273-276 ◽  
Author(s):  
P. HATAMI ◽  
H. PEYROVAN ◽  
H. AFARIDEH ◽  
S. SHOJAEI

Mineral trace element concentration of human saliva from healthy volunteers, were investigated by Proton-Induced X-ray Emission (PIXE) analysis. The specimens were bombarded with Proton beams of 2 MeV from a Van de Graaff accelerator at NRC . The object of this measurement was to find a normal range of trace element concentration for Iranian people.


Forests ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1072 ◽  
Author(s):  
Teresa Enes ◽  
José Aranha ◽  
Teresa Fonseca ◽  
Carlos Matos ◽  
Ana Barros ◽  
...  

Research Highlights: Biomass from Mediterranean agroforestry vegetation may be a potential source of renewable energy. However, due to the high heterogeneity of this type of resource, the study of its characteristics becomes necessary for its efficient use. Objectives: The aim of this study was to evaluate the thermal and chemical properties of 14 different kinds of agroforestry biomass groups: shrubs, forest, and agricultural wastes. Materials and Methods: The higher heating value (HHV), the elemental analysis (C, H, O, N, S), ashes, mineral elements (Na, K, Ca, Mg, and P), trace elements (Mn, Fe, Zn, Ni, Cu, Cr, and Cd) and halogen elements (F and Cl) were quantified and compared with CEN/TS 147775 and CENS/TS 14961 standards, looking forward to future use for energy purposes, namely through combustion processes, as an alternative to fossil fuels. Results: The shrubs present the highest values of higher heating value (20.5 MJ kg−1), followed by the forest wastes (19.2 MJ kg−1) and the lowest in the agricultural wastes (18.5 MJ kg−1). Concerning the elemental analysis, the difference between groups C, H, and O are very small and not statistically significant, while for N, S and ashes values are higher in agricultural than shrubs and forestry wastes. The same tendency was found for the mineral nutrients. For the trace elements, the lowest content of Mn, Fe, and Zn is found in agricultural, Ni, and Cr content in the shrubs and Cu in the forest wastes. The halogen elements are present in greater amount in shrubs than agricultural and forest wastes. Conclusions: Although the high values of the halogen elements which may raise sintering problems and corrosive effect on metal parts in furnace and boiler, in general the shrubs biomass are those with better characteristics for energy uses, namely through combustion processes.


1997 ◽  
Vol 07 (03n04) ◽  
pp. 201-209
Author(s):  
Shiro Sakurai ◽  
Masae Yukawa

The purpose of this study is to analyze quantitatively trace elements in human organs without decomposing samples. A palladium thin layer was deposited onto a sample on carbon adhesive tape using a metal ion sputtering equipment. The Pd film was used as an internal standard to determine concentrations of trace elements in human liver. Bovine Liver was applied as the reference standard. Five elements Cu , Zn , Mn , Se and Fe were measured by this method. The values of Copper, Zinc and iron concentrations determined by PIXE using this method agree well with those by ICP-AES. It can he asserted that this method is quite useful in the study of non-destructive PIXE analysis.


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