Go toArchive
Browse byFacets
Bookbag ( 0 )
'electrical properties' in keywords
Results  4 Items
Sorted by   
Publication Year
1992 (1)
1989 (2)
1976 (1)
1Author    G. Chiodelli, V. Campari-Viganò, G. Massarotti, FlorRequires cookie*
 Abstract    The electrical behaviour of La2_JtSrJ.Cu04_v solid solutions (with x = 0, x = 0.025, x = 0.05, and x = 0.15) at temperatures between 10 and 900 K and under different oxygen partial pressure pQl — 1 -M0~6 atm) has been investigated. The samples prepared and measured under an 0 2 flux (i.e~, with y = 0) show a superconducting transition with Tc = 46, 29. 37 K for x = 0. 0.05 and"0.15, respectively. The samples with x = 0.025, y = 0, and x = 0, y = t= 0 exhibit no sign of superconductivity. In the temperature range 100-900 K. La2Cu04 is semiconducting, whereas the electrical resistivity is independent of temperature for the x =0.025 sample, and the x = 0.05 and x = 0.15 are metallic. 
  Reference    Z. Naturforsch. 44a, 26—28 (1989); received September 19 1988 
  Published    1989 
  Keywords    Superconductors, electrical properties, defects 
  Similar Items    Find
 TEI-XML for    default:Reihe_A/44/ZNA-1989-44a-0026.pdf 
 Identifier    ZNA-1989-44a-0026 
 Volume    44 
2Author    G. Chiodelli, G. Campari-Viganò, G. FlorRequires cookie*
 Title    Y B a 2C  
 Abstract    u 30 7 _ x : T r a n s p o r t P r o p e r tie s an d D e fe c ts a t H ig h T e m p e r a tu r e Electrical resistivity measurements were carried out on polycrystalline YBa2Cu,07_ v at temper­ atures 300 < T < 1023 K and oxygen partial pressures 5 ■ 10"7 < p0l < 1 atm. The samples, equili­ brated in the range from 5 10~4 to 1 atm, show metallic behaviour, the one equilibrated at p0, = 2 • 10"5 shows a transition between metallic and semiconducting behaviour at 920 K, and that equilibrated at p0i — 5-10" shows semiconducting behaviour: for the latter the relevant resistivity is due to the oxygen-ion migration. The isotherms log a vs. log (in the temperature range from 723 to 1023 K) show slopes of about 1/6 at 723 K (orthorhombic phase) and about 1/2 at 1023 K (tetragonal phase). These results are discussed in terms of appropriate defect models. 
  Reference    Z. Naturforsch. 44a, 1167—1171 (1989); received September 28 1989 
  Published    1989 
  Keywords    Superconductors, electrical properties, defects 
  Similar Items    Find
 TEI-XML for    default:Reihe_A/44/ZNA-1989-44a-1167.pdf 
 Identifier    ZNA-1989-44a-1167 
 Volume    44 
3Author    G. Küche3, J. K. Öhler3, W. BauhoferbRequires cookie*
 Title    Röntgenographische, elektrische und spektroskopische Untersuchungen an den Palladiumchalkogeniden P d S ^ S e * Roentgenographic, Electrical and Spectroscopic Investigations of the Palladium Chalcogenides P d S ^ S e  
 Abstract    Silvery reflecting melting cakes o f P d S ^ S e * (0.0 < jc < 1.0) have been prepared by annealing mixtures o f Pd, S and Se at 873 K in evacuated quartz tubes. The PdS-type mixed crystals are stable only in the ranges 0.0 < .x < 0.2 and 0.9 < x < 1.0, whereas a new phase appears in the intermediate region. The new phase P dS|_vSev (0.2 < x < 0.9) crystallizes in the space group P 42/m bc and Z = 24. Lattice constants are a = 1126.2(7), c = 683.2(7) pm (PdS0 6Se04) and a = 1130.8(9), c = 685.4(8) pm (PdS04Se0 6). The relationships between the new structure type and the PtS and PdS structure types are discussed. The infrared reflection spectra o f polycrystalline samples o f PdS were measured between 10 and 300 K in the frequency range from 30 to 400 cm -1. Both phonons and plasmons contrib­ ute to the spectra. The temperature dependence o f the plasmon contribution shows an unusual behaviour which is explained by the assumption o f a phonon assisted hopping conductivity mechanism at low temperatures and a Drude-like transport at high temperatures. The normal mode which may be involved in the hopping process is proposed from a normal coordinate calculation using a three-parameter short range valence force field model. The electrical trans­ port data are in general agreement with the optical ones. The infrared spectra o f the mixed crystals P d S ^ S e,. (0.2 < x < 1) are discussed. 
  Reference    Z. Naturforsch. 47b, 383—3 (1992); eingegangen am 31. Juli 1991 
  Published    1992 
  Keywords    Palladium Sulfide, Palladium Selenide, Far-Infrared Reflection Spectra, Electrical Properties, Hopping Conductivity 
  Similar Items    Find
 TEI-XML for    default:Reihe_B/47/ZNB-1992-47b-0383.pdf 
 Identifier    ZNB-1992-47b-0383 
 Volume    47 
4Author    GünterG. NollRequires cookie*
 Title    A Cell for Simultaneous Measurements of Optical and Electrical Properties of Black Lipid Membranes  
 Abstract    A universal cell was constructed, which allows measurements of the resistance (d. c.), capacity, optical reflectivity, and spectral absorption of blade lipid films simultaneously. These measurements reflect different properties of the films, supplementary to each other. The purpose is to eliminate differences of experimental conditions especially in recombination experiments with proteins. The cell is totally symmetric, can be completely disassembled, and the parts are exchangeable. It allows application of several methods for film production, and is held together simply by mechanical pressure, without need of any sealing agent. The inner parts are exclusively of glass and teflon. The fluid volume of the cell is 7 —15 ml and the better than 1014 Ohms. 
  Reference    (Z. Naturforsch. 31c, 40—43 [1976]; received September 22 1975) 
  Published    1976 
  Keywords    Black Lipid Membranes, Simultaneous Measurements, Optical Properties, Electrical Properties, Recombination Experiments 
  Similar Items    Find
 TEI-XML for    default:Reihe_C/31/ZNC-1976-31c-0040.pdf 
 Identifier    ZNC-1976-31c-0040 
 Volume    31