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21.
Sandro FADDA Alessandro RIVOLDINI Ignazio CAU 《Geostandards and Geoanalytical Research》1995,19(1):41-54
The microwave oven acid digestion technique has been routinely applied to the ICP-MS multielement analysis of whole powdered coal. Samples were treated with a mixture of HF/aqua regia/HClO4 in closed Teflon PFA vessels without any pre-treatment. Complete dissolution of the coal matrix is not required, but only one that results in quantitative and reproducible recovery of more than 40 trace elements with minimum digestion time, minimum use of reagents and minimal operator attendance. The precision of the analysis as well as the repeatability of the sample preparation procedure and precision of instrumental measurements have been evaluated. Eight coal standards, including NBS SRM 1632b, 3 South Africa Reference Materials (SARMs) 18 to 20 and 4 USA ARs 1800 to 1803 were analysed in this manner providing data for all the 14 rare earth elements along with others of geochemical interest, technological relevance as well as environmental and health concern. The results, from the ppb level to several ppm, are discussed for all the elements including detection and quantification limits, precision and accuracy. In general, good agreement was achieved with the certified and/or available published values. 相似文献
22.
Dr. Ignazio Dagnino 《Pure and Applied Geophysics》1952,21(1):43-48
Riassunto Per 52 località del Bacino del Mediterraneo ed adiacenze sono state calcolate le prime tre componenti armoniche dell'andamento annuo della pressione atmosferica in base alle rispettive medie mensili. La distribuzione dei valori della prima armonica permette di dedurre che dal punto di vista climatico il Bacino del Mediterraneo può venir distinto in cinque parti, aventi ciascuna caratteristiche diverse nei confronti dell'andamento considerato.
Summary The first three harmonic components of the annual variation of the atmospheric pressure have been calculated on the basis of their respective monthly averages for 52 localities on the basin of the Mediterranean and adjoining regions. The repartition of the values of the first harmonic component allows the deduction that from the climatic point of view, the basin of the Mediterranean can be divided into five parts, each one having different characteristics compared to the movement under consideration.相似文献
23.
Dr. Ignazio Dagnino 《Pure and Applied Geophysics》1948,12(3-4):162-167
Riassunto L'A. riferisce sulla livellazione di precisione da lui eseguita per determinare le quote assolute dei caposaldi esterni ed
interni dell'Istituto Geofisico e Geodetico dell'Università di Genova, con collegamento allo zero mareografico locale.
Zusammenfassung Der Verf. berichtet über das von ihm durchgeführte Feinnivellement um die vertikale Lage einiger Festpunkten des Geophysikalisch-Geod?tischen Instituts der Universit?t Genua genau zu bestimmen und zwar mit Verbindung an die dortige mareographische Station.相似文献
24.
Lili Cafarella Stefano Urbini Cesidio Bianchi Achille Zirizzotti Ignazio E. Tabacco Alessandro Forieri 《Polar research》2006,25(1):69-73
Radio echo sounding (RES) measurements were collected from 1995 to 2003 during Italian Antarctic expeditions over the Vostok-Dome C region. The data collected allow for the reconstruction of a bedrock elevation map between the Belgica Highlands and the Aurora Subglacial Basin (112.0ø - 124.0ø E; 74.0ø - 78.0ø S). Moreover, analysis of the RES data has revealed one of the thickest ice covers in Antarctica (4755 Ø 16 m; 118.321ø E, 76.059ø S) as well as five new subglacial lakes. 相似文献
25.
Weather radars in investigating physical characteristics of precipitation are becoming essential instruments in the field of short term meteorological investigation and forecasting. To analyze the radar signal impact in hydrological forecasting, precipitation input fields, generated through a statistical mathematical model, are supplied to a distributed hydrological model. Such a model would allow the control of the basin response to precipitation measurements obtained by a meteorological radar and, in the meanwhile, to evaluate the influence of distributed input. The distributed model describes the basin hydrological behavior, subdividing it into distinct geometrical cells and increasing the physical significance by reproducing the distributed hydrographic basins characteristics, such as infiltration capacity, runoff concentration time, network propagation speed, soil moisture influence. Each basin cell is characterized by its geological, pedological and morphological status, and may be considered a unitary hydrological system, linked to the others by geomorphological and hydraulic relationships. To evaluate the dynamics of the flood event a synthetic representation of the channel network is introduced, where each stream branch is modeled as a linear reservoir. Finally, the discharge in the outlet section is derived, taking into account the hydraulic characteristics of the upstream branches. 相似文献
26.
Riassunto Viene descritto ed illustrato un nuovo procedimento di registrazione del moto ondoso marino, il quale consiste sostanzialmente nel trasformare l'escursione verticale che subisce la superficie del mare nella compressione o dilatazione di una massa d'aria sovrastante racchiusa in un tubo verticale munito superiormente di opportuna membrana sensibile. Un tale apparecchio, installato a Prà (Genova) dal-l'Istituto Geofisico dell'Università di Genova, funziona con successo da alcuni mesi. Segue un esame dei primi risultati ivi conseguiti, dal quale appare l'importanza del passaggio dei fronti freddi sul moto ondoso del mare.
Summary A new method for the recording of sea-wave motion is described and explained. It consists in having the vertical movement of the sea surface transformed into compression or expansion of a volume of air enclosed in a tube which is carrying on its upper part a sensitive membrane. This self-recording instrument, set up at Prà (Genoa) by the Istituto Geofisico dell'Università di Genova is functioning since several months already without giving rise to objections. Some first results obtained up now are also examided, from which it appears the importance of the passage of cold fronts.
Zusammenfassung Es wird ein neues Verfahren für die Registrierung der Meereswellenbewegung beschrieben und erläutert. Es besteht darin, dass der vertikale Gang der Meeresoberfläche umgewandelt wird in Kompression oder Expansion einer in einem Rohre befindlichen Luftmasse, welche am oberen Teil von einer empfindlichen Membran geschlossen ist. Dieser Gerät, vom Istituto Geofisico dell'Università di Genova in Prà (Genua) aufgestellt, arbeitet bereits seit einigen Monaten einwandfrei. Einige vorläufige Ergebnisse werden dann erläutert, wofür auf die Bedeutung des Durchganges von Kaltfronten hingewiesen wird.相似文献
27.
Ignazio Ciufolini Erricos C. PavlisAntonio Paolozzi John RiesRolf Koenig Richard MatznerGiampiero Sindoni Karl Hans Neumayer 《New Astronomy》2012,17(3):341-346
In this paper we respond to the criticisms of “Phenomenology of the Lense-Thirring effect in the Solar System” by Iorio et al. about the general relativistic phenomena of gravitomagnetism and frame-dragging. The claims of the paper by Iorio et al. are not reproducible in any of our independent analyses. 相似文献