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Trace Element Contents (trace + element_content)
Selected AbstractsAn ethnoarchaeological study of chemical residues in the floors and soils of Q'eqchi' Maya houses at Las Pozas, GuatemalaGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 6 2002Fabián G. Fernández This ethnoarchaeological study at the Q'eqchi' Maya village of Las Pozas, Guatemala, aimed to refine the understanding of the relationship between soil chemical signatures and human activities for archaeological applications. The research involved phosphorus, exchangeable ion (calcium, potassium, magnesium, sodium), and trace element analysis of soils and earth floors extracted by Mehlich II, ammonium acetate, and DTPA chelate solutions, respectively. The results showed high levels of phosphorus, potassium, magnesium, and pH in food preparation areas, as well as high phosphorus concentrations and low pH in food consumption areas. The traffic areas exhibited low phosphorus and trace element contents, whereas refuse disposal areas were enriched. These results provide important information for the understanding of space use in ancient settlements. © 2002 Wiley Periodicals, Inc. [source] THE COMPOSITION OF TWO SPANISH PEPPER VARIETIES (FRESNO DE LA VEGA AND BENAVENTE-LOS VALLES) IN DIFFERENT RIPENING STAGESJOURNAL OF FOOD QUALITY, Issue 6 2008ANA BERNARDO ABSTRACT The chemical composition of two traditional varieties of Spanish peppers, "Fresno de la Vega" and "Benavente-Los Valles" harvested in the provinces of León and Zamora, respectively, at different ripening stages (green mature, breaker and red) were evaluated. Herein we report the global composition, mineral and trace element contents, and the most relevant physicochemical parameters of each variety of pepper collected in 2 consecutive years. Both pepper varieties showed a similar chemical composition, except in vitamin C content, which resulted to be about 70% higher in Fresno de la Vega peppers. Red ripe fruits were high in total carbohydrates, fructose, glucose, sucrose, fat (64.5, 29.14, 25.57, 2.94, 1.79/100 g dry weight, respectively) and total soluble solids (6.83°Brix). Ascorbic acid content also increased progressively during ripening, reaching a mean value of 1.81 mg/100 g dry weight for Fresno de la Vega peppers. Potassium was the most abundant of the analyzed elements in the all samples, followed by phosphorus, magnesium, calcium and sodium. The order of the levels of the trace elements was iron > manganese > zinc > copper. PRACTICAL APPLICATIONS This report underscores the potential value of two traditional varieties of Spanish peppers and provides information on their composition during ripening to decide the proper harvesting time, which can be useful in the food industry. [source] Chemical variation within fragments of Australasian tektitesMETEORITICS & PLANETARY SCIENCE, Issue 6 2005Trinh Hai SON No data for intra-sample trace element variations existed. Thus, we sectioned a Muong Nong-type tektite fragment from Vietnam and a splash-form tektite fragment from the Philippines into eleven and six pieces, respectively, and analyzed the individual fragments for major and trace element contents. The compositions obtained agree well with those found in previous studies, supporting argument that tektites have been derived from terrestrial upper crustal sediments. Chemical variations within the tektite fragments are present, but do not show any systematic trends, probably reflecting incomplete mixing of parent rocks. The intra-sample heterogeneity of the Muong Nong-type tektite is more pronounced than that in the philippinite. For the Muong Nong-type tektite, the intra-sample variation in the trace element contents is higher than that for the major elements, again reflecting target rock properties. For the philippinite the intra-sample variations mostly do not exceed the limits imposed by the precision of the analytical data, confirming that the splash form tektites are indeed well homogenized. [source] Effects of dietary zinc levels on growth, serum zinc, haematological parameters and tissue trace elements of soft-shelled turtles, Pelodiscus sinensisAQUACULTURE NUTRITION, Issue 3 2010S.-C. HUANG Abstract A 10-week feeding trial was conducted to evaluate the effects of dietary zinc (Zn) contents on the growth, tissue trace element contents and serum Zn levels in soft-shelled turtles, Pelodiscus sinensis. Juvenile soft-shelled turtles approximately 4.8 g in body weight were fed casein-based diets containing seven levels of Zn (14, 23, 32, 43, 58, 87 and 100 mg kg,1) for 10 weeks. There were no significant differences (P > 0.05) in weight gain (WG), feed conversion ratio (FCR) or protein efficiency ratio (PER) among the dietary treatments. However, Zn concentrations in the liver, serum and carapace of turtles fed the basal diet containing 14 mg Zn kg,1 were the lowest among all groups. Zn contents in the liver, serum and carapace increased when dietary Zn increased up to a dietary Zn level of approximately 43 mg kg,1. Beyond this dietary level, tissue Zn contents were relatively constant. Carapace iron (Fe), selenium (Se) in hard tissues and haemoglobin concentrations decreased when dietary Zn increased. Dietary Zn requirements of juvenile soft-shelled turtles derived from regression modelling using the liver, serum, carapace and bone Zn contents as indicators were 42, 39, 35 and 46 mg Zn kg,1, respectively. [source] Petrological characterisation of ,alabaster' from the Marib province in Yemen and its use as an ornamental stone in Sabaean cultureARABIAN ARCHAEOLOGY AND EPIGRAPHY, Issue 1 2009Christian Weiss ,Yemen alabaster', a calcareous sinter, is a unique building and ornamental stone of the Sabaean culture (c. 1000 BC to 100 AD). This study characterises the quarries and describes the facies of their stones. Through thin sections, luminescence microscopy and geochemical analyses, ,Yemen alabaster' can be classified and assigned a quarry source. The stone is a calcareous sinter related to volcanism in the Marib province. It can be divided into several microfacies types different in luminescence and trace element contents. During Sabaean times it was mined in highly organised quarries including underground quarries and used extensively in the Sabaean kingdom. [source] | ||||||||||