Trace element distribution among rock-forming minerals from metamorphosed to partially molten basic igneous rocks in a contact aureole (Fuerteventura, Canaries)

Low pressure partial melting of basanitic and ankaramitic dykes gave rise to unusual, zebra-like migmatites, in the contact aureole of a layered pyroxenite-gabbro intrusion, in the root zone of an ocean island (Basal Complex, Fuerteventura, Canary Islands). These migmatites are characterised by a dense network of closely spaced, millimetre-wide leucocratic segregations. Their mineralogy consists of plagioclase (An(32-36)), diopside, biotite, oxides (magnetite, ilmenite), +/-amphibole, dominated by plagioclase in the leucosome and diopside in the melanosome. The melanosome is almost completely recrystallised, with the preservation of large, relict igneous diopside phenocrysts in dyke centres. Comparison of whole-rock and mineral major- and trace-element data allowed us to assess the redistribution of elements between different mineral phases and generations during contact metamorphism and partial melting. Dykes within and outside the thermal aureole behaved like closed chemical systems. Nevertheless, Zr, Hf, Y and REEs were internally redistributed, as deduced by comparing the trace element contents of the various diopside generations. Neocrystallised diopside - in the melanosome, leucosome and as epitaxial phenocryst rims - from the migmatite zone, are all enriched in Zr, Hf, Y and REEs compared to relict phenocrysts. This has been assigned to the liberation of trace elements on the breakdown of enriched primary minerals, kaersutite and sphene, on entering the thermal aureole. Major and trace element compositions of minerals in migmatite melanosomes and leucosomes are almost identical, pointing to a syn- or post-solidus reequilibration on the cooling of the migmatite terrain i.e. mineral-melt equilibria were reset to mineral-mineral equilibria. (C) 2007 Elsevier B.V. All rights reserved.

Effect of anionic salts on some blood and urine minerals, acid-base balance and udder oedema of dry pregnant cows

Selostus: Anionisten suolojen vaikutus ummessa olevien lehmien veren ja virtsan kivennäisiin, happo-emästasapainoon sekä utarepöhöön

Niobium and rare earth minerals from the Virulundo carbonatite, Namibe, Angola

The Virulundo carbonatite in Angola, one of the biggest in the world, contains pyrochlore as an accessory mineral in all of the carbonatite units (calciocarbonatites, ferrocarbonatites, carbonatite breccias, trachytoids). The composition of the primary pyrochlore crystals is very close to fluornatrocalciopyrochlore in all these units. High-temperature hydrothermal processes caused the pseudomorphic replacement of the above crystals by a second generation of pyrochlore, characterized by lower F and Na contents. Low-temperature hydrothermal replacement of the above pyrochlores, associated with production of quartz-carbonates-fluorite veins, controled the development of a third generation of pyrochlore, characterized by high Sr contents. Finally, supergene processes produced the development of a secondary paragenesis in the carbonatite, consisting in late carbonates, goethite, hollandite and REE minerals (mainly synchysite-(Ce), britholite-(Ce), britholite-(La), cerite-(Ce)). Separation of Ce from the other REE was allowed by oxidizing conditions. Therefore, Ce4+ was also incorporated into a late generation of pyrochlore, which is also strongly enriched in Ba and strongly depleted in Ca and Na

Fertilització agrària dels cereals d’hivern a la Catalunya Central

Les comarques de la Catalunya Central conformen una de les àrees cerealístiques més importants de Catalunya, de fet la més important en secà, ja que el clima d’un tipus més subhumit permet produccions regulars i més elevades que en algunes de les comarques veïnes. En aquestes comarques la ramaderia és també, com a molts indrets de la Catalunya interior, força important i on el porquí té un pes molt elevat. La fertilització de base orgànica complementada quan i on escaigui amb fertilitzants minerals pot ésser la millor solució agronòmica, ambiental i econòmica. Perquè això sigui així cal primer un bon coneixement del comportament d’aquests fertilitzants orgànics en aquests sistemes agraris situats en climes menys àrids que els de la Catalunya de Ponent, i a més cal que aquesta informació arribi a tècnics, pagesos i diversos operadors que hi ha al territori. Per això l’objectiu de l’estudi d’aquesta publicació és omplir un buit d’informació que existia mitjançant la col·laboració amb la Universitat de Lleida amb la posada en marxa d’una sèrie de camps experimentals distribuïts al llarg de tota la zona, on les diferents variables: tipus de fems, moment d’aplicació, etc. eren assajades. Al mateix temps es va posar en marxa tot un seguit de treballs amb col·laboració directa amb els pagesos i ramaders, on se’ls orientava en la millor pràctica de fertilització agronòmica, ambiental i econòmica; tot això amb la idea de fer una taca d’oli, que aquests agricultors, capdavanters en molts casos, estenguessin entre els seus veïns propers aquest concepte. Tot això conforma el que s’anomena Pla de Millora de la Fertilització de la Catalunya Central. La finalitat era doncs oferir, sobre unes sòlides bases experimentals, un consell d’adobat robust que el poguessin assumir els diferents prescriptors en fertilització que d’aquesta manera es van posar sobre el territori. Acabada aquesta primera fase és moment de fer balanç, resumir les actuacions i posar-les en un format assequible i que sigui fàcilment disponible. Això és el que fa aquesta publicació. Aquests treballs del Pla de fertilització van néixer amb vocació d’adaptar-se a les canviants situacions social i econòmica i a l’avenç del coneixement que representen. Ara s’ha donat continuïtat a aquests treballs per part del DAAM, tenint en compte el grau de coneixement assolit i donant continuïtat a alguns dels camps experimentals bàsics, amb l’enfocament de fer sostenible el sistema agrícola i ramader que hi ha a la comarca i que és la base de la seva economia. Ajustant-se al marc abans esmentat, amb la col·laboració de tots els agents participants anteriors es busca en aquesta nova fase incrementar els coneixements bàsics, omplint els buits existents, mantenir els prescriptors en fertilització sobre el territori i incrementar l’eficiència en l’ús dels recursos esmerçats. Fruit d’aquesta experiència i d’altres en diferents indrets de Catalunya, el DAAM està potenciant aquest model d’adquisició de coneixement i transferint-lo al sector mitjançant l’anomenada Xarxa de Plans de fertilització, que hores d’ara cobreix una part molt significativa de Catalunya i que es vol potenciar.

Sugars, organic acids, minerals and lipids in jabuticaba

The aim of this work was to determine the sugar, organic acid and mineral compositions of the whole fruit and fractions (skin, pulp and seed) of the Paulista (Plinia cauliflora) and Sabará (Plinia jaboticaba) jabuticaba tree genotypes, as well as the oil compositions of their skin and seeds. High levels of sugar, especially fructose, followed by glucose and sucrose, were encountered in the fruit. In the Paulista genotype, higher levels of total and reducing sugars were found in the pulp and skin, which was not observed when comparing the whole fruit of both genotypes. Five organic acids were found in the whole fruit and in the fractions of the two jabuticaba genotypes in quantitative order: citric acid > succinic acid > malic acid > oxalic acid > acetic acid. Potassium was the most abundant mineral found. This fruit was also shown to be rich in magnesium, phosphorus, calcium and copper. The seed oil had nearly the same constitution as the oil extracted from the skin in both genotypes and the major compounds were an unidentified phytosterol, palmitic, linoleic and oleic acids, and squalene.

La promoció de vendes de les marques d'aigües minerals en la distribució organitzada: el cas de Mercadona

La popularització de productes naturals i d’hàbits de vida saludables, ha contribuït a estimular la demanda de tota mena de d’articles vinculats a la salut com l’aigua mineral natural, que els últims anys, ha passat de ser una “commodity" a un producte de valor afegit. La conjuntura social i econòmica dels últims anys, també ha condicionat els hàbits de consum de les famílies. En alguns casos, la reducció del poder adquisitiu ha motivat l’estalvi en tota mena de productes i serveis fet que ha beneficiat les marques privades o de distribuïdor, sovint considerades inferiors en qualitat però també en preu, i que d’ara en endavant anomenarem (MDD). Els distribuïdors han recolzat els productes MDD millorant-ne la qualitat, la presentació i han invertit en estratègies de comunicació, fet que, ha suposat un increment de la quota de mercat en totes les categories de bens de consum favorable a les MDD. El present treball, pretén dur a terme un anàlisi comparatiu dels preus de venda al públic de les aigües minerals naturals a la cadena Mercadona, i de les estratègies promocionals seguides per tal d’afavorir la MDD vers les marques de fabricant (MDF).

Minerals and essential fatty acids of the exotic fruit Physalis peruviana L.

Physalis peruviana is an exotic fruit that belongs to the Solanaceae family and which has recently started to be produced in Brazil, mainly in the Southern region. Once there is few data regarding its chemical composition, this work presents the centesimal and mineral composition and the fatty acid profile of the lipidic fraction of Physalis peruviana. Concerning the centesimal composition, Physalis presented high contents of ashes and total lipids, 0.8 and 3.16 g.100 g-1, respectively. In its mineral composition, K, Mg, Ca and Fe were the main elements, and Fe is present in concentrations higher than those in the common sources such as beans. The lipidic fraction presented predominance of the linoleic acid (72,42%) in its composition.

Effect of soaking and cooking on phytate concentration, minerals, and texture of food-type soybeans

The increasing consumption of soybeans due to its bioactive compounds has attracted interest in describing the grain's constituents and variation during processing. Phytate has been the aim of much research since it chelates essential minerals but also has beneficial antioxidant effects. This study evaluated the variation of phytate, calcium, zinc, and iron during soaking and cooking of soybeans. The phytate: Zn and phytate: Fe molar ratios were determined in order to estimate the bioavailability of these minerals. Six food-type varieties were used: BR 36, BRS 213, BRS 216, BRS 232, BRS 155, and Embrapa 48. The samples were soaked in water 3:1 (w/w) for 12 hours at room temperature and cooked. Cooking time was determined by modeling the softening of each variety using fractional conversion. Water content, phytate, and minerals were determined in raw, soaked and cooked samples. The water content of raw grains for all varieties was 9.9 g.100 g-1 increasing to a range of 58.1-63.7 g.100 g-1 after soaking and 63.1-66.0 g.100 g-1 after cooking. Soaking caused a significant reduction in phytate (23-30%), but cooking caused no additional reduction. The phytate: Zn molar ratio was 20 indicating that zinc absorption could be impaired, while the phytate: Fe molar ratio was 8, below the level of compromising absorption

Physicochemical composition, minerals, and pesticide residues in organic grape juices

Demand for organic products is intensified in many countries each year. Following this trend, Brazil produces increasing volumes of organic grape juice. In this way, a survey of organic grape juices made from grapes produced according to this system was carried out where physicochemical composition, minerals, trace elements, and pesticide residues were determined. Variables related to grape juice composition were performed by physicochemical procedures; minerals and trace elements, by inductively plasma optical emission spectrometry; pesticide residues, by liquid chromatography-mass spectrometry. Main results show that the physicochemical composition of organic grape juices was in general in accordance to the Brazilian legislation. The mean concentrations of trace elements were very low, varying from 0.002 (Cd) to 0.970 (Ba) mg L–1. Pesticide residues were not detected in any sample analyzed (MRL= 10 µg L–1). These results show that the Serra Gaúcha viticultural region present conditions to produce organic grape juices, despite the adverse climate factors that occurs in some years. Nevertheless, these products should be made with grape varieties, such as the labrusca ones, less susceptibles to the main grapevine pathogens.

Impact of different drying parameters on color, β-carotene, antioxidant activity and minerals of apricot (Prunus armeniacaL.)

Abstract Apricot is one of the fruits dried by using different methods, such as sun, convective or microwave drying. The effects of drying methods on the components of this fruit differ depending upon the temperature or time parameters. In this research, the impacts of convective, microwave and microwave–convective drying techniques on color, β-carotene, minerals and antioxidant activity of apricots were investigated. The color values (L*, b*,ΔEab, h° and C*ab) of dried fruit were decreased, while the a* values increased. Compared with a fresh sample, the dried apricots showed a 1.4-3.9-fold proportional increase in β-carotene based on the increment of dry matter. The samples dried at high temperature and microwave levels, at 75 °C+90 watt and 75 °C+160 watt, showed lower antioxidant activity. Of the different drying treatments, the microwave-convective method (50 °C+160 watt) obtained a higher β-carotene content while maintaining antioxidant activity with a short drying time.

Spectral Reflectance Characteristics of Kimberlite Indicator Minerals and Other Selected Mineral Grains

High chromium content in kimberlite indicator minerals such as pyrope garnet and diopside is often correlated with the presence of diamonds. In this study, kimberlite indicator minerals were examined using visible light reflectance spectroscopy to determine if chromium content can be correlated with spectral absorption features. The depth of absorption features in the visible spectral region were correlated with the molecular percentage of chromium and other first series transition metal elements obtained by electron microprobe data. In the visible part of the spectrum, chromium is evident by 3 absorption features in the pyrope reflectance spectrum; one isolated and narrow feature at the wavelength 689 nm was used to correlate with the chromium mol %. The isolation of this feature in the pyrope spectra is advantageous since it is not directly affected by other proximal absorption bands that could be caused by other transition metals. Analysis of the feature indicates that as grain volume increases the depth of the absorption feature will also increase. Clustering grain volumes into fractions yields better correlation between absorption depth and mol % chromium. Other types of garnet (almandine, grossular, spessartine) and kimberlite indicator minerals (olivine, diopside, chromite, ilmenite) were analyzed to determine if other absorption features could be used to predict the proportion of specific transition metal elements. Diopside in particular illustrates the same isolated chromium absorption feature as pyrope and may indicate mol percent but needs further study with larger sample sets.

Accounting for Human Rights Violations Risk: Conflict Minerals Mandatory Disclosures under the Dodd Frank Act

This paper examines the equity market response to firms’ disclosure of human rights violation risk with regard to conflict mineral usage as required by Section 1502 of the Dodd-Frank Act (the Act). This paper assesses the aggregate equity market response to regulatory events leading to the passage of the Act, the equity market reaction to voluntary early disclosures and mandatory disclosures of conflict mineral information in Form SD, as well as the determinants of the equity market response. Using a sample of 4,399 US registrants from January 1, 2008 to September 30, 2014, we document a significant negative stock market reaction to the passage of the Act and to conflict minerals disclosures on Form SD. The equity market reaction is more negative and limited to companies that source their minerals from conflict zones, companies with human rights violations, and companies with ambiguous disclosures. Taken together, the results of this study provide an economic justification for companies with poor conflict minerals practices to improve in order to avoid high costs that will arise if firms are forced to disclose human rights abuses. This paper also provides preliminary evidence that Form SD is successful in reducing the governance gap that exposes investors to unnecessary sanction, litigation and reputation risk from firms’ activities in conflict minerals usage.

Aproximació a l'estudi dels minerals a Cicle Inicial i Mitjà. 'Aproximación al estudio de los minerales en el Ciclo Inicial y Medio'.

Resumen basado en el de la publicación. Monográfico con el título: 'Geologia: idees i recursos educatius'

Minerals.

Los minerales son sustancias sólidas que forman las rocas y se originan en el interior profundo de la Tierra a elevadas temperaturas. Diferentes combinaciones de elementos forman diferentes minerales, los cuales pueden identificarse por su color, veta, forma, dureza, densidad, brillo. Los minerales han sido extraídos de los metales y piedras preciosas que los contienen, y se han utilizado para la pintura, la cerámica, las joyas e, incluso para dispositivos electrónicos. Al final del libro hay una pequeña bibliografía y direcciones de páginas web.