Thermal properties of Nb from acoustic and electrical resistivity measurements in the temperature range 60–340 K

1976 ◽  
Vol 47 (1) ◽  
pp. 17-21 ◽  
Author(s):  
Gaetano Cannelli ◽  
Giovanni Bosco Cannelli
2003 ◽  
Vol 793 ◽  
Author(s):  
Matthieu Puyet ◽  
Bertrand Lenoir ◽  
Anne Dauscher ◽  
Hubert Scherrer ◽  
Moukrane Dehmas ◽  
...  

ABSTRACTThe transport properties of the partially filled CaxCo4-yNiySb12 skutterudite compounds have been investigated in the 300 – 800 K temperature range. We underline the positive influence of the Ni substitution on the electrical resistivity and thermopower while the thermal properties – thermal conductivity – remains almost unaffected. These results suggest again a beneficial effect of Ni atoms on the dimensionless figure of merit in CoSb3 based compounds.


1996 ◽  
Vol 10 (07) ◽  
pp. 299-303
Author(s):  
MISBAH UL ISLAM ◽  
M. SHAKEEL BILAL ◽  
T. ABBAS ◽  
M.U. RANA ◽  
S. MOHSIN RAZA

Measurements on the electrical resistivity of Mn 1−x Zn x Fe 2 O 4 ferrites with 0<x< 0.15 in the temperature range 300 K <T<450 K , have been carried out. Analysis of the normalised electrical resistivity of these ferrites shows deviations from linearity both at low and high temperatures. There exists a deviation in the electrical resistivity at 300 K at high zinc concentration which may be due to hopping of electrons between Fe +2 and Fe +3 ions at octahedral sites.


2002 ◽  
Vol 16 (28n29) ◽  
pp. 1143-1149 ◽  
Author(s):  
ASHUTOSH TIWARI ◽  
H. WANG ◽  
D. KUMAR ◽  
J. NARAYAN

We here report the manifestation of weak localization effects in the electrical resistivity of TaN (001) films grown on MgO (001) substrates by a pulsed laser deposition technique. These films were characterized by X-ray diffraction and Rutherford backscattering. High precision electrical resistivity measurements were performed on these films in the temperature range 12–300 K. A careful analysis of data showed these films to lie in the weakly localized regime with negative temperature coefficient of resistivity throughout the whole temperature range of study. A crossover from 2D localization at lower temperatures to 3D localization at higher temperatures was observed.


1995 ◽  
Vol 09 (03n04) ◽  
pp. 195-200 ◽  
Author(s):  
S. M. M. R. NAQVI ◽  
S. DABIR H. RIZVI ◽  
S. MOHSIN RAZA ◽  
MUSHTAQ AHMAD GORMANI ◽  
N. FAROOQUI

Electrical resistivity measurements of amorphous ( Fe x Co 100-x)83 B 17 alloys in the temperature range 40 K < T < 300 K have been obtained. We observed from the analysis of the resistivity data that there is no s-d interaction or Js-d coupling. An empirical relationship for estimating Θ D is suggested from the normalized electrical resistivity data, which holds good both for theoretical and estimated Θ D . For s-d interaction or Js-d coupling to occur in ferromagnetic amorphous alloys, ordering of ferromagnetic domains, i.e. Heisenberg interaction in a disordered matrix, would require temperatures of T ≤ Θ D /50 ≃ 0.02 Θ D .


Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3160 ◽  
Author(s):  
Alfonso Pozio ◽  
Zoran Jovanovic ◽  
Silvano Tosti

Hydrogen retention in Pd–Ag (silver 21 wt. %) thin foil has been tested by means of temperature-programmed desorption (TPD) in the temperature range 25–200 °C and compared to the resistivity measurements for the purpose of explaining the characteristic S-shaped resistivity curve and its minimum observed in the same temperature range. The TPD results indicated that the highest uptake of hydrogen was between 65 °C and 105 °C, with a maximum at ~85 °C. Furthermore, in all examined cases, the hydrogen desorption peak was between 140 °C and 180 °C. The resistivity measurements in argon, hydrogen, and vacuum allowed us to examine the influence of hydrogen on the resistivity of a Pd–Ag alloy. The results showed evidence of two kinds of hydrides: (1) a weak absorption at low temperature (T < 70 °C) with the hydrogen present mainly in tetrahedral sites, and (2) a strong absorption up to 150 °C with the hydrogen present mainly in octahedral sites. The behaviour of the electrical resistivity and the minimum between 90 °C and 110 °C can be explained by the two kinds of hydrogen uploaded into the metal lattice.


2015 ◽  
Vol 60 (3) ◽  
pp. 1603-1608 ◽  
Author(s):  
T. Gancarz ◽  
J. Pstruś

Abstract The aim of this work was to study the effects of Ag and Cu on the thermal properties and microstructure of Sn-Zn-Ag-Cu cast alloys. Solders based on eutectic Sn-Zn containing 0.5 to 1.0 at.% of Ag and Cu were developed for wave soldering. DSC measurements were performed to determine the melting temperatures of the alloys. TMA and electrical resistivity measurements were performed between −50 and 150°C and between 30 and 150°C, respectively. Small precipitates of Cu5Zn8, CuZn4, and AgZn3 were observed in the microstructures, and their presence was confirmed by XRD measurements. The inclusion of Ag and Cu improved the electrical resistivity and increased the melting temperature, as well as the CTE, of the alloys. However, tests performed to measure the mechanical properties of the alloys demonstratedthat the addition of Ag and Cu caused the mechanical properties to decrease.


Author(s):  
W. E. King

A side-entry type, helium-temperature specimen stage that has the capability of in-situ electrical-resistivity measurements has been designed and developed for use in the AEI-EM7 1200-kV electron microscope at Argonne National Laboratory. The electrical-resistivity measurements complement the high-voltage electron microscope (HVEM) to yield a unique opportunity to investigate defect production in metals by electron irradiation over a wide range of defect concentrations.A flow cryostat that uses helium gas as a coolant is employed to attain and maintain any specified temperature between 10 and 300 K. The helium gas coolant eliminates the vibrations that arise from boiling liquid helium and the temperature instabilities due to alternating heat-transfer mechanisms in the two-phase temperature regime (4.215 K). Figure 1 shows a schematic view of the liquid/gaseous helium transfer system. A liquid-gas mixture can be used for fast cooldown. The cold tip of the transfer tube is inserted coincident with the tilt axis of the specimen stage, and the end of the coolant flow tube is positioned without contact within the heat exchanger of the copper specimen block (Fig. 2).


1967 ◽  
Vol 6 (47) ◽  
pp. 599-606 ◽  
Author(s):  
Hans Röthlisberger

A brief description of the resistivity method is given, stressing the points which are of particular importance when working on glaciers. The literature is briefly reviewed.


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