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  • 1
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Solid state phenomena Vol. 32-33 (Dec. 1993), p. 21-26 
    ISSN: 1662-9779
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Physics
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Electrical engineering 64 (1982), S. 313-324 
    ISSN: 1432-0487
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Description / Table of Contents: Übersicht Der Aufsatz beschreibt eine analytische Methode zur Berechnung des magnetischen Feldes eines unbelasteten supraleitenden Wechselstromgenerators mit beliebiger Anzahl von Polpaaren unter Berücksichtigung der endlichen Länge der Maschine und der effektiven Dicke der Windungen. — Die Methode wird angewendet auf eine zweipolige Maschine mit 1200 MVA zur Bestimmung der Flußdichte innerhalb des Generators. — Die Diagramme zeigen, daß die Einbeziehung der Windungsdicke eine Erhöhung des Feldes innerhalb der Windungen ergibt. Die Werte weichen erheblich von denen mit anderen analytischen Methoden berechneten ab, in denen jede Windung durch Leiterstreifen ersetzt wird.
    Notes: Contents The paper presents an analytical method for the calculation of the magnetic field in a no-load superconducting alternator having any number of pole-pairs, bearing in mind the finite length and end-regions of the machine and the effective thickness of the windings. The method was applied to the preliminary design of a two-pole machine of about 1200 MVA in order to obtain the values of the components of the flux density at all points inside the generator. The diagrams obtained show that the consideration of the effective thicknesses of the windings in calculations may sometimes give rise, in the region of the windings themselves, to magnetic field distributions and values very different from those obtained using other analytical methods in which each winding is represented by one or morc current sheets.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Electrical engineering 62 (1980), S. 141-151 
    ISSN: 1432-0487
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Description / Table of Contents: Übersicht Im Rahmen der vorliegenden Abhandlung werden die radialen und tangentialen Komponenten des magnetischen Feldes innerhalb eines dreiphasigen, mit supraleitender Feldwicklung ausgeführten Turbogenerators mit rotierender Abschirmung an Hand einer ebenen Betrachtung stationär und transient berechnet. Die darin angegebenen Beziehungen gelten für beliebige Ordnung der Feldharmonischen und für beliebige Polpaarzahlen des Generators, wobei die Dicke der Rotor- und Statorwicklung endlich ist und die Wirbelstromverteilung den tatsächlichen Verhältnissen entspricht. Am Beispiel eines zweipoligen leerlaufenden Turbogenerators von ca. 1300 MVA mit zweifacher Rotorabschirmung wurde die Verteilung der magnetischen Flußdichte, deren Oberwellengehalt sowie das stationäre und transiente Verhalten der rotierenden Abschirmung untersucht.
    Notes: Contents In this paper, the radial and tangential components of the magnetic field inside a three-phase turbogenerator with superconducting field winding and with a rotating screen of any number of elements are calculated with reference to a twodimensional study and to steady state and transient running. The expressions obtained are valid for any order of the field harmonic and any number of pole-pairs of the generator, and refer to a finite thickness of the rotor and stator windings and take account of the real distribution of the eddy currents in the screen elements. As an example of the applications, with reference to a preliminary design for a two-pole turboalternator of around 1300 MVA with “double” rotor screen, the distribution of the flux density with no load and its content of harmonics are found and the steady state and transient behaviour of the rotor screen is analyzed.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Electrical engineering 71 (1988), S. 139-148 
    ISSN: 1432-0487
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Description / Table of Contents: Übersicht Untersuchungen über Magnetschwebeverkehrsysteme mit elektrodynamischer Abstoßung (EDS-MAGLEV) erregen heutzutage ein großes Interesse. Die vorliegende Abhandlung beschreibt ein analytisches dreidimensionales Verfahren für die Berechnung der Trag-Bewegungswiderstand-und Seitlichkräfte auf Magnetschwebefahrzeugen mit supraleitenden und/oder konventionellen Spulen, egal welche Anzahl, Anordnung und Ausdehnung sie haben. Die Anwendung dieses Verfahrens auf die Versuchsanlagen zeigt eine gute Übereinstimmung mit den Versuchsdaten.
    Notes: Contents The researches on magnetically levitated transport systems with electrodynamic suspension (EDS-MAGLEV systems) are today of great interest. The paper describes an analytical three-dimensional method which allows the determination of the levitation, drag and lateral forces acting on EDS-MAGLEV systems with superconducting and/or conventional coils, whatever their number, disposition and sizes may be. The application of the method to experimental prototypes shows a good concordance with the experimental data.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Electrical engineering 72 (1989), S. 333-339 
    ISSN: 1432-0487
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Description / Table of Contents: Übersicht Im Artikel wird ein analytisch-dreidimensionales Verfahren beschrieben, das die Berechnung der Antriebskraft erlaubt, die bei überschnellen Beförderungssystemen wie EDS-MAGLEV durch lineare Langstator-Synchronmotoren entsteht, wobei Supraleitungsspulen sowohl zur Motorerregung als auch zur magnetischen Levitation des Fahrzeuges verwendet werden. Das Verfahren berücksichtigt die endliche Spulendicke und geht aus von der Änderung der magnetischen Energie, die in den Anker- und Erregerwicklungen (Zylinder- sowie Wellenwicklungen) des Motors gespeichert ist. Die Werte der Antriebskraft, die durch die Anwendung dieses Verfahrens auf einen in Japan ausgeführten Experimentalprototyp ermittelt werden, weisen eine gute Übereinstimmung mit den experimentellen Werten auf.
    Notes: Contents The paper describes an analytical three-dimensional method which allows the determination of the propulsion force produced by air core long stator linear synchronous motors in EDS-MAGLEV transport systems, using super-conducting coils both for motor field winding and for vehicle levitation. The method, which allows to take into account the finite thickness of the coils, is based on the variation of the magnetic energy stored in the field and armature (over-lapped or non-overlapped) windings of the motor. The application of the method to an experimental Japanese prototype gives good concordance with the experimental data.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Environmental geology 36 (1998), S. 195-206 
    ISSN: 1432-0495
    Keywords: Key words Groundwaters ; Nitrate ; Pollution ; Subsidence ; Urban Areas ; Italy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract  More than 5 800 chemical analyses on water samples collected during 1987–1995 from 528 monitoring wells located in the southernmost part of the Po Valley (Emilia-Romagna region, northern Italy), one of the most urbanized, industrialized and agriculturally developed areas of Italy, have been processed. The analysis of data showed that: (1) waters are discharging from both confined and unconfined aquifers; (2) the water in the unconfined aquifer(s) is Ca(Mg)-HCO3 in composition while confined ones are Na-Cl and/or Na-(HCO3); (3) both confined and unconfined aquifer samples have δ18O and δD isotopic values of meteoric signature; (4) waters from both the aquifers are at least 40 years old; (5) the pumping rate has caused subsidence, particularly where the aquifer(s) is (are) unconfined; (6) the unconfined aquifer(s) is exposed to the risk of NO3 pollution; (7) considering the present "pressure" (i.e. pumping rate) on this natural environment by human activity, care must be taken in the future to preserve this "strategic" resource.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1432-0487
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Description / Table of Contents: Übersicht Der Aufsatz benutzt eine dreidimensionale analytische Methode zur Berechnung der Werte und der Verteilung der elektromagnetischen Kräfte in elektrischen Systemen mit Sattelspulen. Die Methode erlaubt die Berechnung der Kräfte pro Volumeneinheit, der Drücke und die auf die Spulen wirkenden Gesamtkräfte unter Berücksichtigung der endlichen Länge. Die Methode wird auf einen zweipoligen supraleitenden Magnet und auf einen supraleitenden Synchrongenerator angewendet.
    Notes: Contents The paper utilizes a three-dimensional analytical method in order to determine the values and distribution of electromagnetic forces acting on electrical systems provided with saddle coils. The method permits the calculation of the forces per unit volume, the pressures and the total forces acting on the coils, taking into account the end zones. Two application examples are given, referring to a dipole superconducting magnet and to a superconducting turboalternator.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Advances in science and technology Vol. 45 (Oct. 2006), p. 205-208 
    ISSN: 1662-0356
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Natural Sciences in General , Technology
    Notes: Aim of the work is to compare the morphological properties of TiO2 powders obtained bydifferent methods. The microstructure of powders is a fundamental parameter to judge if thematerial is suitable for gas sensing. Materials for chemical sensors have to be composed bynanometric and spherical shaped grains sintered in controlled conditions aimed to obtain Schottkybarriers. We investigated a traditional sol-gel (SG) and an hydrothermal (HY) approach to obtaintitanium dioxide powders. The same starting materials were chosen for both SG and HY method, aTi-organometallic precursor and, as solvent, an hydroalcoholic solution. The work is focused on thedifferent methodology and on the outcome related to the two methods (we describe step by stepboth of them). HY TiO2 powder shows smaller grains than SG TiO2 maintaining spherical shape. Acomparison among different handled HY powders shows the role of dwelling time (at fixedtemperature) on the nanostructure of grains. Experimental observations are mainly based on XRDand SEM analyses
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Advances in science and technology Vol. 45 (Oct. 2006), p. 1818-1827 
    ISSN: 1662-0356
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Natural Sciences in General , Technology
    Notes: The main semiconductor oxides for gas sensing have been examined, describing thesynthesis processes and the morphological and structural properties. The powders have beendeposited as thick films through screen-printing technique to achieve gas sensors. The sensinglayers have been studied with regard to semiconductor behaviour, surface barrier potential heightsand gas sensing properties. The interaction of humidity with semiconductor oxides has beenconsidered with the aim to compensate, using an algorithm, its effect in gas detection. Finally,nitrogen oxides monitoring, contemporaneously performed in several sites of Italy, has beendescribed
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Solid state phenomena Vol. 47-48 (July 1995), p. 455-462 
    ISSN: 1662-9779
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Physics
    Type of Medium: Electronic Resource
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