Two varieties of lithiophorite in some Australian deposits

1984 ◽  
Vol 48 (348) ◽  
pp. 383-388 ◽  
Author(s):  
J. Ostwald
Keyword(s):  
Mixed Layer ◽  
Electron Probe ◽  
Marked Change ◽  
Alumina Content ◽  
Transition Elements ◽  
Zn Content ◽  
Cu And Zn

Abstract Electron probe microanalyses carried out on thirty areas of lithiophorite (Al,Li)MnO2(OH)2 from five Australian localities indicate wide variations in its Ni, Co, Cu, and Zn content. The concentration of these elements varies inversely with the alumina content, though there is a marked change in their concentration at 18% alumina, suggesting the existence of two varieties of lithiophorite with differing concentration of transition elements. EPMA line scans also indicate definite changes in Co content in lithiophorite grains less than 0.2 mm in dimension. The variations in alumina and transition elements may be explained if lithiophorite is considered to be an irregular mixed-layer-lattice intergrowth of pure lithiophorite with members of the recently discovered asbolane-type minerals.

scholarly journals Assessment of heavy metals in soils of a vineyard region with the use of principal component analysis

2009 ◽  
Vol 66 (3) ◽  
pp. 361-367 ◽  
Author(s):  
Gustavo Souza Valladares ◽  
Otávio Antônio de Camargo ◽  
José Ruy Porto de Carvalho ◽  
Alessandra Maria Cia Silva
Keyword(s):  
Heavy Metals ◽  
Principal Component Analysis ◽  
Agricultural Soils ◽  
Principal Component ◽  
Component Analysis ◽  
Soil Samples ◽  
Metal Concentrations ◽  
Zn Content ◽  
Heavy Metals In Soils ◽  
Cu And Zn

Agricultural management with chemicals may contaminate the soil with heavy metals. The objective of this study was to apply Principal Component Analysis and geoprocessing techniques to identify the origin of the metals Cu, Fe, Mn, Zn, Ni, Pb, Cr and Cd as potential contaminants of agricultural soils. The study was developed in an area of vineyard cultivation in the State of São Paulo, Brazil. Soil samples were collected and GPS located under different uses and coverings. The metal concentrations in the soils were determined using the DTPA method. The Cu and Zn content was considered high in most of the samples, and was larger in the areas cultivated with vineyards that had been under the application of fungicides for several decades. The concentrations of Cu and Zn were correlated. The geoprocessing techniques and the Principal Component Analysis confirmed the enrichment of the soil with Cu and Zn because of the use and management of the vineyards with chemicals in the preceding decades.

scholarly journals Differences in the Activity of Superoxide Dismutase, Polyphenol Oxidase and Cu-Zn Content in the Fruits of Gordal and Manzanilla Olive Varieties

2002 ◽  
Vol 57 (1-2) ◽  
pp. 113-120 ◽  
Author(s):  
Dámaso Hornero-Méndez ◽  
Lourdes Gallardo-Guerrero ◽  
Manuel Jarén-Galán ◽  
María Isabel Mínguez-Mosquera
Keyword(s):  
Superoxide Dismutase ◽  
Polyphenol Oxidase ◽  
Copper Content ◽  
Redox Balance ◽  
Sod Activity ◽  
Activity Peak ◽  
Olive Variety ◽  
Zn Content ◽  
Olive Varieties ◽  
Cu And Zn

Activity of the enzymes superoxide dismutase (SOD) and polyphenol oxidase (PPO) as well as Cu-Zn content have been monitored during the thirteen weeks growth of both Gordal and Manzanilla olive variety fruits. These metalloenzymes, with Cu and Zn in the prostetic group, are involved in controlling the redox balance in the chloroplast environment. The results indicated that, under similar phenological and environmental conditions, there are periodic peaks of SOD activity in both varieties, followed by fluctuations in the copper content of the fruit. This was interpreted as a common and simultaneous response to situations of oxidative stress, and this response was more intense in the variety Gordal. The enzyme PPO showed an activity peak at start of growth and then practically disappeared. Thus, its activity cannot be correlated with situations of stress or with changes of Cu and Zn in the fruit.

Accumulation of Copper and Zinc in the Yellow Water Lily, Nuphar variegatum: Relationships to Metal Partitioning in the Adjacent Lake Sediments

1985 ◽  
Vol 42 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Peter G. C. Campbell ◽  
André Tessier ◽  
Marc Bisson ◽  
René Bougie
Keyword(s):  
Lake Sediments ◽  
Sediment Cores ◽  
Protective Role ◽  
Water Lily ◽  
Geochemical Fractions ◽  
Fe Content ◽  
Zn Content ◽  
Nuphar Variegatum ◽  
Cu Bioavailability ◽  
Cu And Zn

Relationships between the partitioning of Cu and Zn in lake sediments and their availability to the yellow water lily, Nuphar variegatum, were examined downstream from a major Cu/Zn mining and smelting complex in Northwestern Quebec, Canada. At each of 13 sampling sites, five N. variegatum individuals were collected, separated into stem and rhizome portions, and analyzed for total Cu and Zn. At the same sites, sediment cores were collected at the base of each plant; the 0- to 2-cm stratum was extruded, wet sieved (850 μm), and subjected to a sequential leaching procedure to determine the partitioning of Cu and Zn among various operationally defined geochemical fractions. Statistical analysis suggested that a significant portion of the Cu burden in N. variegatum was probably derived from the sediments, whereas the Zn content of the plant originated largely in the water column. The concentrations of Cu in the fractions most readily extracted from the sediment were the best indicators of Cu bioavailability in the sediment; normalization of these concentrations with respect to the Fe content of the sediment improved the relationship with [Curhizome], suggesting that Fe may play a protective role in regulating Cu bioavailability.

scholarly journals The impact of various grape stock cultivars on the As, Cu, Co and Zn content of the grape berry (must, seed)

2013 ◽  
pp. 39-44
Author(s):  
István Fekete ◽  
Nándor Rakonczás ◽  
Dávid Andrási ◽  
Éva Bódi ◽  
Szilárd Szilágyi ◽  
...  
Keyword(s):  
Toxic Elements ◽  
Grape Berry ◽  
Potentially Toxic Elements ◽  
Grape Berries ◽  
Zn Content ◽  
Abnormal Increase ◽  
Set Up ◽  
Arsenic Copper ◽  
The Impact ◽  
Cu And Zn

Scientific research from the last decades showed that the inappropriate industrial and agricultural production caused an abnormal increase of the potentially toxic elements in the soil. Unfortunately the acidification of the soil is an increasing problem in Hungary. According to Várallyay et al. (2008) 13% of the Hungarian soils are highly acid. Accumulation of toxic elements differs in the genetically diverse plant species. The root of the plant constitutes a filter so that the rootstock is also kind of a filter system, which may prevent that the scion part (such as berry) accumulate high levels of various potentially toxic elements from the soil. The aim of research was to determine how different grape rootstocks influence the As, Co, Cu and Zn content of the musts and seeds. Thus, specifying which of the grape rootstocks takes up the lowest level of these 4 elements (As, Co, Cu and Zn), and accumulates in berries, so could reduce the potentially toxic element load of the grape berries. The grape rootstock collection of the University of Debrecen was set up in 2003 in 3x1 m spacing on immune sandy soil. Grafting of ‘Cserszegi fűszeres’ was started in 2010. We could evaluate yields harvested from 12 rootstock varieties of the experiment in October 2011. We obtained valuable differences in the arsenic, copper, cobalt and zinc concentrations of musts and seeds of ‘Cserszegi fűszeres’ grafted into different rootstocks. The results obtained from the 2011 harvest support the statement that the choice of rootstock might be an important factor to increase food safety. The differences in concentration of the four elements observed in case of the rootstock may have been caused on one hand by the rootstock effect, and on the other hand, the vintage effect has a very significant impact on the vines element uptake. Several years of experimental results will be needed to answer these questions.

scholarly journals The effect of copper and zinc concentrations in feed and water on their distribution in beef cattle tissues

2007 ◽  
Vol 23 (5-6-2) ◽  
pp. 35-48 ◽  
Author(s):  
M. Vukasinovic ◽  
V. Kaljevic ◽  
M. Sekler ◽  
V. Kurcubic ◽  
S. Obradovic
Keyword(s):  
Beef Cattle ◽  
Muscular Tissue ◽  
Correlation Dependence ◽  
Copper And Zinc ◽  
Maximum Permissible Concentrations ◽  
Zn Content ◽  
Zinc Concentrations ◽  
Aas Method ◽  
Effect Of Copper ◽  
Cu And Zn

An investigation of the effect of copper (Cu) and zinc (Zn) concentrations on their distribution in beef cattle tissues was conducted using feed trial with the following four nutrition treatments applied. At the end of the trial, samples of the muscular tissue, liver and kidneys of slaughtered cattle were taken from 10 head of cattle of the I group, 30 head of the II and III groups and 15 head of the IV group. The analyses were made by using the spectroscopic AAS method. Investigation results showed that all groups of cattle were given water with Cu and Zn contents below maximum permissible concentrations (MPC). The content of Cu and Zn in the tissues of the beef cattle in our experiment directly depended on their content in the concentrated feed. Copper is deposited in the liver the most, and Zn in the muscular tissue (excepting the II group of cattle). Correlation dependence of Cu and Zn content in the tissues from content in DM is complete (total), except in the case of Zn content in kidney, where is above mentioned correlation very strong (0.795).

The effect of N and P application on the Mn, Cu and Zn content of the winter wheat

1996 ◽  
pp. 499-502 ◽  
Author(s):  
Z. Gyôri ◽  
L. Ruzsányi ◽  
L. Jászberényi ◽  
I. Vágó ◽  
J. Loch
Keyword(s):  
Winter Wheat ◽  
Zn Content ◽  
P Application ◽  
Cu And Zn

Effect of Magnesium Deficiency on Enterocyte Ca, Fe, Cu, and Zn Content

2002 ◽  
pp. 340-340
Author(s):  
E. Planells ◽  
N. Sanchez-Morito ◽  
P. Aranda ◽  
J. Llopis
Keyword(s):  
Magnesium Deficiency ◽  
Zn Content ◽  
Cu And Zn

Quantitative Measurement of Iron-Silicides by EPMA Using the Fe Lα and Lβ X-ray Lines: A New Twist to an Old Approach

2019 ◽  
Vol 25 (3) ◽  
pp. 664-674 ◽  
Author(s):  
Aurélien Moy ◽  
John Fournelle ◽  
Anette von der Handt
Keyword(s):  
Calibration Curve ◽  
Electron Probe ◽  
Accurate Determination ◽  
Electron Transition ◽  
Electron Interaction ◽  
Transition Elements ◽  
Close Proximity ◽  
Schottky Type ◽  
Silicide Compounds ◽  
Takeoff Angle

AbstractThe recent availability of Schottky-type field emission electron microprobes provides incentive to consider analyzing micrometer-sized features. Yet, to quantify sub-micrometer-sized features, the electron interaction volume must be reduced by decreasing accelerating voltage. However, the K lines of the transition elements (e.g., Fe) then cannot be excited, and the L lines must be used. The Fe Lα1,2 line is the most intense of the L series but bonding effects change its atomic parameters because it involves a valence band electron transition. For successful traditional electron probe microanalysis, the mass absorption coefficient (MAC) must be accurately known, but the MAC of Fe Lα1,2 radiation by Fe atoms varies from one Fe-compound to another and is not well known. We show that the conventional method of measuring the MAC by an electron probe cannot be used in close proximity to absorption edges, making its accurate determination impossible. Fortunately, we demonstrate, using a set of Fe–silicide compounds, that it is possible to derive an accurate calibration curve, for a given accelerating voltage and takeoff angle, which can be used to quantify Fe in Fe–silicide compounds. The calibration curve can be applied to any spectrometer without calibration and gives accurate quantification results.

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