Search results for "otas"

Gavina capblanca, Gaviota picofina (VER0000111)

Altres noms vulgars: Slender-billed Gull (Anglès), Goéland railleur (Francès), Dünnschnabelmöwe (Alemany) Gabinet de Vertebrats (Departament de Zoologia), Facultat de Ciències Biològiques (Campus de Burjassot), C/ Doctor Moliner, s/n, Bloque B. 5é plant, Burjassot (Valencia). Armari: 8-1 Mar Menor

Heavy metal sorption in the lichen cationactive layer.

2007

Results of copper ion sorption in lichens owing to the ion exchange between the surroundings (aqueous solution) and the lichen cationactive layer have been presented. It indicates that the course of sorption of these ions, similarly as in the case of cations of other heavy metals, depends on the concentration and type of cations naturally found in lichen surroundings: H+, Na+, K+, Mg2+ and Ca2+. A determination method of heavy metal concentration in lichen surroundings has been proposed. It consists in exposure of transplanted lichens in the presence of salts that provide precisely determined, artificial salinity of precipitation with which the lichens are in contact. The studies were condu…

Phosphoraneiminato complexes of manganese and cobalt with heterocubane structure

1999

The phosphoraneiminato complexes [MnBr(NPEt3)]4 (1) and [M4Br5{NP(NMe2)3}3] with M = Mn (2) and M = Co (3) are prepared by melting reactions from the anhydrous metal dibromides with the silylated phosphaneimines Me3SiNPR3 (R = Et, NMe2) in the presence of potassium fluoride. All complexes are characterized by crystal structure analyses. 1 forms an only slightly distorted Mn4N4 heterocubane skeleton with an approximate Td symmetry and short Mn…Mn distances of average 295.7 pm. In the structures of 2 and 3 one μ3-NPEt3 ligand of 1 is replaced by one bromine atom with μ3-function. This leads to the novel heterocubane type M4N3Br with approximate C3 symmetry. The deformation of the cubic skelet…

Geochemical characteristics of Cretaceous carbonatites from Angola

1999

Abstract The Early Cretaceous (138–130 Ma) carbonatites and associated alkaline rocks of Angola belong to the Parana-Angola-Etendeka Province and occur as ring complexes and other central-type intrusions along northeast trending tectonic lineaments, parallel to the trend of coeval Namibian alkaline complexes. Most of the Angolan carbonatite-alkaline bodies are located along the apical part of the Mocamedes Arch, a structure representing the African counterpart of the Ponta Grossa Arch in southern Brazil, where several alkaline-carbonatite complexes were also emplaced in the Early Cretaceous. Geochemical and isotopic (C, 0, Sr and Nd) characteristics determined for five carbonatitic occurren…

Vironkielisten osallistujien kielitaito Yleisten kielitutkintojen suomen kielen testissä 

2021

Tarkastelemme tässä artikkelissa vironkielisten suomen oppijoiden osallistumista Suomen kansallisen kielitestin, Yleisten kielitutkintojen, keskitason tutkintoon ja heidän kielitaitoprofiiliaan tutkintotulosten valossa. Vertaamme tuloksia yleiseen tutkintomenestykseen sekä osallistujien taustaan ja pohdimme suomen kielen asemaa oppimisen kohteena vironkielisten näkökulmasta. Analyysimetodina käytämme kuvailevaa tilastollista analyysia sekä tilastollista päättelyä. Tulokset osoittavat, että vironkieliset osallistujat menestyvät tutkinnossa hyvin ja erityisesti ymmärtämistaidot ovat tutkitussa ryhmässä vahvat. Vaikka aiemman tutkimuksen valossa suomen kielen taidon tason onkin nähty riippuvan…

Potassium-inhibited processing of IL-1 beta in human monocytes.

1995

Agents that deplete cells of K+ without grossly disrupting the plasma membrane were found to stimulate the cleavage of pro-interleukin (IL)-1 beta to mature IL-1 beta. Agents examined in this study included staphylococcal alpha-toxin and gramicidin, both of which selectively permeabilize plasma membranes for monovalent ions, the ionophores nigericin and valinomycin, and the Na+/K+ ATPase inhibitor ouabain. K+ depletion by brief hypotonic shock also triggered processing of pro-IL-1 beta. The central role of K+ depletion for inducing IL-1 beta maturation was demonstrated in cells permeabilized with alpha-toxin: processing of pro-IL-1 beta was totally blocked when cells were suspended in mediu…

Macrocycles prepared from lithocholic acid, piperazine and isomeric pyridine dicarboxylic acids and their selective affinities towards sodium and pot…

2001

Abstract Two novel macrocycles prepared from lithocholic acid, piperazine and pyridine dicarboxylic acids (2,6- and 3,5-isomers), have been characterized by 13C NMR and ESI–MS techniques. In case of the pyridine-2,6-dicarboxylate derivative, the molecular formula of the cycle was C59H87O6N3 (I), while the pyridine-3,5-dicarboxylate derivative (II) was a trimeric structure by molecular mass when compared with I. Furthermore, cycle I showed a special affinity towards potassium cation, while II possessed significant proton and sodium cation recognition properties.

Gamma activity and geochemical features of building materials: estimation of gamma dose rate and indoor radon levels in Sicily.

2001

A high-purity germanium detector has been used to measure the abundance of radium (Ra), thorium (Th) and potassium (K) in building materials used in Sicilian dwellings. The measurements were performed to evaluate which material was suitable for the construction of an enclosure, which would have a low background emission. The materials examined in this work showed concentrations of 226Ra, 232Th and 40K dramatically variable depending on the lithologies, particularly in the case of blocks, sands and aggregates commonly used in building materials in Sicily. The results are discussed and a criterion is indicated to reduce the radiation dose to humans. Since radon inlet is a major health problem…

Photoinduced chemiluminescence of pharmaceuticals

2005

Abstract A screening test for the forward development of chemiluminescence systems able to determine pharmaceutical compounds is reported. The test is based on the on-line photodegradation of the drugs by using a photoreactor consisting of 697 cm × 0.5 mm PTFE tubing helically coiled around an 8 W low-pressure mercury lamp. Photodegraded pharmaceuticals are detected by direct chemiluminescence of the resulting photofragments and their subsequent reaction with potassium permanganate in sulphuric acid medium as oxidant. The screening comprised 97 compounds with different molecular structures and relevant members of the most important families of pharmaceuticals are tested (amino acids, carbox…

Use of QSAR methods for predicting the chemiluminescent behaviour of organic compounds upon reaction with potassium permanganate in an acid medium

2009

In previous work, molecular connectivity computations were successfully used to predict the chemiluminescent behaviour of organic compounds upon reaction with common strong oxidants and the native fluorescence too; both of them in a liquid phase. The obtained results were used to develop new analytical procedures to the given compounds. For the first time, connectivity methods were used for a purely analytical purpose. In this work, we went deeper into the knowledge of direct chemiluminescence processes by using molecular connectivity in the form of QSAR methods to predict the chemiluminescence intensity produced by reactions between organic compounds (pharmaceuticals mainly) and potassium …