Search results for "PELE"

Disequilibrium carbon and oxygen isotope fractionation in recent cave calcite: Comparison of cave precipitates and model data

2013

Abstract Speleothem proxy data provide important information in continental palaeo-climate research due to their precise chronology and wide geographic distribution. Despite a continuously growing number of field and numerical studies designed to study stable isotope fractionation effects, many aspects remain a matter of debate. Here, carbon and oxygen isotope ratios from cave drip water and calcite precipitates sampled on watch glasses in the Bunker Cave (Western Germany) are compared with the values expected for isotopic equilibrium. Furthermore, the field data are compared with the results of a numerical model simulating stalagmite growth and stable isotope ratios. Two drip sites with di…

Are oxygen isotope fractionation factors between calcite and water derived from speleothems systematically biased due to prior calcite precipitation …

2021

Abstract The equilibrium oxygen isotope fractionation factor between calcite and water (18αcalcite/H2O) is an important quantity in stable isotope geochemistry and allows in principle to infer temperature variations from carbonate δ18O if carbonate formation occurred in thermodynamic equilibrium. For this reason, many studies intended to determine the value of the oxygen isotope fractionation factor between calcite and water (18αcalcite/H2O) for a wide range of temperatures using modern cave calcite and the corresponding cave drip water or ancient speleothem carbonate and fluid inclusion samples. However, the picture that emerges from all of these studies indicates that speleothem calcite i…

The effects of drip rate and geometry on the isotopic composition of speleothems: Evaluation with an advection-diffusion-reaction model

2022

Abstract The curvature and slope of speleothem surfaces have been shown to affect the reaction rates in the aqueous carbonate system by altering the thickness of the CaCO3-precipitating solution. However, the effects of speleothem geometry and drip rate on the speleothem’s carbon and oxygen isotopic composition have yet to be investigated. Over more strongly sloping surfaces, solutions are thinner and flow faster. The effects of thinner and faster-flowing solutions on the isotopic composition of carbonate minerals precipitated from these solutions are of opposite sense. Thinner solutions enhance rates of CO2 degassing and mineral formation, increasing the degree of isotopic distillation of …

SISALv2: a comprehensive speleothem isotope database with multiple age–depth models

2020

Characterizing the temporal uncertainty in palaeoclimate records is crucial for analysing past climate change, correlating climate events between records, assessing climate periodicities, identifying potential triggers and evaluating climate model simulations. The first global compilation of speleothem isotope records by the SISAL (Speleothem Isotope Synthesis and Analysis) working group showed that age model uncertainties are not systematically reported in the published literature, and these are only available for a limited number of records (ca. 15 %, n = 107/691). To improve the usefulness of the SISAL database, we have (i) improved the database’s spatio-temporal coverage and (ii) create…

Occurrence of Yersinia ruckeri infection in farmed whitefish, Coregonus peled Gmelin and Coregonus muksun Pallas, and Atlantic salmon, Salmo salar L.…

1986

Yersinia ruckeri, the aetiological agent of enteric redmouth disease (ERM), is now generally recognized to be distributed worldwide. The pathology and epizootiology of the disease was first described by Rucker (1966) and although rainbow trout, Salmo gairdneri Richardson, has been the most frequently affected species, all salmonids are now considered to be potential hosts for the organism (McDaniel 1979). The present paper reports the first confirmed occurrence of Y. ruckeri infection in farmed whitefish and Atlantic salmon, Salmo salar L., in Finland, with the known host range being extended to include the whitefish Coregonus peled Gmelin and Coregonus muksun Pallas . The outbreaks of infe…

Pelicà, Pelícano común (VER0000063)

Altres noms vulgars: Great white pelican (Anglès), Pélican blanc (Francès), Rosapelikan (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: 5-2 Valencia Macho

Pelicà rosat, Pelícano rosado (VER0000193)

1968

Pink-backed pelican (Anglès), Pélican gris (Francès), Rötelpelikan (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: 9-1 Centro Europa 00/00/1968 Macho Adulto

Rodolfo Walsh en 'ese hombre': un escritor a diario, su memoria en los papeles

2013

Resumen: Este articulo integra dos tipos de lectura critica de Ese hombre y otros papeles personales (Buenos Aires, 1996 y 2007), de Rodolfo Walsh, con edicion a cargo de Daniel Link. Considerando, primero, el diario del escritor que incluye, el libro describe, dentro del pathos caracteristico del genero, las imposibilidades y los fracasos de la escritura, que especifican historicamente los problemas de la relacion entre literatura y politica, propios del campo argentino de los anos ’60-’70. Las tensiones de la escritura y la vida, agudizadas cuando apremia la militancia, y expresadas en las disyuntivas de genero –basicamente, novela  vs. testimonio- constituyen, en esa linea, un eje crucia…

Autovadītāja identifikācija, izmantojot OBD2 datus

2019

Mūsdienās attīstošās datizraces tehnoloģijas un metodes ir radījušas lielu interesi par dažādiem ievāktajiem datiem. Ar 1996. g. ASV un 2003. g. ES, visiem šajās teritorijas tirgotajiem transportlīdzekļiem jābūt aprīkotiem ar OBD2, kas ir sensoru datu apstrādes standarts. Iepriekš veiktie pētījumi ir pierādījuši, ka ir iespējams no šiem datiem identificēt braucēju, ja tie tiek vākti strikti kontrolētos eksperimentos ar noteiktiem maršrutiem un braukšanas laikiem. Šajā darbā tika apskatīts, vai ir iespējams identificēt braucēju no maza sensoru skaita OBD2 datiem, kas ir ievākti no 8 autobraucējiem vadot vienu transportlīdzekli dažādos apstākļos. Datu klasifikācijai tika izmantota programma W…

Physicochemical characteristics of drip waters: Influence on mineralogy and crystal morphology of recent cave carbonate precipitates

2014

Speleothems are one of the most intensively explored continental archives for palaeoclimate variability. The parameters, however, that control speleothem petrography and its changes with time and space, specifically calcite crystal morphology and carbonate mineralogy, are still poorly understood. In order to shed light on processes and their products, precipitation experiments of recent carbonate crystals on watch glasses and glass plates were performed in seven selected caves. Drip water sites were analysed for their fluid Mg/Ca molar ratio, pH, degree of saturation for calcite and aragonite and drip rates. Corresponding precipitates were analysed with respect to their mineralogy, calcite …