scholarly journals Deviations from Matthiessen's Rule for Platinum

1961 ◽  
Vol 14 (3) ◽  
pp. 352 ◽  
Author(s):  
PG Klemens ◽  
GC Lowenthal
Keyword(s):  
Electronic Band Structure ◽  
Impurity Content ◽  
The Other ◽  
Platinum Resistance ◽  
Electronic Band ◽  
Total Impurity ◽  
Total Impurity Content ◽  
Resistance Thermometry ◽  
Matthiessen's Rule ◽  
Matthiessen’S Rule

An analysis of the resistivity-temperature relationship down to liquid helium temperatures of 17 platinum resistors as determined in various laboratories shows that deviations from Matthiessen's rule can be classed roughly into three groups. One of them follows the pattern predicted by Sondheimer and Wilson's theory. The other two cannot be fully explained in this way, and may be due to the sensitivity of the electronic band structure of transition metals to small concentrations of impurities. The behaviour of a resistor thus depends on the nature as well as the total amount of impurities and imperfection~. In low temperature platinum resistance thermometry the resistors should be selected with regard to the type of residual impurity as well as total impurity content.

scholarly journals On Klemens and Lowenthal's Paper on Deviations from Matthiessen's Rule

1962 ◽  
Vol 15 (3) ◽  
pp. 441
Author(s):  
RJ Berry ◽  
DR Lovejoy
Keyword(s):  
Low Temperature ◽  
Simple Formula ◽  
Platinum Resistance ◽  
Platinum Resistance Thermometers ◽  
Resistance Thermometers ◽  
Conduction Theory ◽  
Resistance Thermometry ◽  
Matthiessen's Rule ◽  
Band Conduction ◽  
Matthiessen’S Rule

In a recent paper on deviations from Matthiessen's rule for platinum Klemens and Lowenthal (1961) classified the deviation patterns, calculated for a number of different platinum resistance thermometers, into three groups, and reported that only one of these groups followed the pattern predicted by Sondheimer and Wilson's (1947) two-band conduction theory. They suggested that if resistors belonging to one particular group (though no matter which group) were selected for use in low temperature platinum resistance thermometry then the resistance-temperature relationship could be expressed accurately by a relatively simple formula. We believe that Klemens and Lowenthal's method of classifying the resistors into groups is open to serious objection and that consequently some of their important conclusions are not necessarily valid.

RELATIONSHIP BETWEEN THE REAL AND IDEAL RESISTIVITY OF PLATINUM

1963 ◽  
Vol 41 (6) ◽  
pp. 946-982 ◽  
Author(s):  
R. J. Berry
Keyword(s):  
Theoretical Expression ◽  
Special Method ◽  
Platinum Resistance ◽  
The Real ◽  
Resistance Function ◽  
Platinum Resistance Thermometers ◽  
Resistance Thermometers ◽  
Measured Resistance ◽  
Matthiessen's Rule ◽  
Matthiessen’S Rule

The relationship between the real and ideal resistance functions (RT/R273) has been examined for a wide variety of specimens of thermometric platinum over the range 0–900° K. An attempt was made to relate these two functions by using Matthiessen's rule in addition to Kohler's theoretical expression for the deviation from Matthiessen's rule. It was found that Kohler's relation did not apply for most specimens of thermometric platinum; however, in the restricted range 20–90° K, it appeared to hold fairly well for about 17 of the 65 resistors examined.Values for the ideal resistance function have been determined by extrapolating the measured resistance values of a large number of platinum resistance thermometers. In the range 10–90° K a special method of extrapolation has been used which appears to give greater accuracy than previously attained. Also, methods for estimating the residual resistance ratio (at 0° K) from measurements at higher temperatures are discussed.The results of this investigation have been applied to the practical problem of extending the present platinum resistance temperature scale below 90.19° K. To this end, a somewhat different method for interpolating the real resistance function between a number of fixed calibration temperatures has been outlined and compared with earlier methods.

Research on H2S Removal from Yellow Phosphorus Off-Gas through Catalytic-Oxidizing under Low Temperature and Oxygen Content

2013 ◽  
Vol 726-731 ◽  
pp. 3971-3975
Author(s):  
Li Juan Jia ◽  
Jun Ming Guo ◽  
Ping Ning
Keyword(s):  
Activated Carbon ◽  
Low Temperature ◽  
Oxygen Content ◽  
Chemical Industry ◽  
Impurity Content ◽  
H2s Removal ◽  
Yellow Phosphorus ◽  
Total Impurity ◽  
Total Impurity Content ◽  
The Ideal

Research was conducted to illustrate relevant questions about H2S removal from yellow phosphorus off-gas through catalytic-oxidizing method. Following results have been found out. Firstly, Molecule sieve ZMS-5A, activated carbon ZP-1, ZP-2, ZP-3 and ZP-4 were used as carrier to identify their performances on H2S removal, among which ZP-4 was the optimum one. Secondly, among 3 different impregnants tested in experiments, Na2CO3 was the ideal one to be used as active ingredients of catalyst. And 7% was the suitable concentration of Na2CO3 according to experiments. Finally, catalyst made of carrier ZP-4 impregnated with 7% Na2CO3 was assessed comprehensively to investigate its performance on impurity removal of PH3, H2S, SO2, COS, and CS2. After purification total impurity content in yellow phosphorus off-gas was less than 10g/Nm3, which means purified gas can be used as material as mono-carbon chemical industry.

scholarly journals Impurities and their Distribution in Temperate Glacier Ice

1976 ◽  
Vol 16 (74) ◽  
pp. 173-181 ◽  
Author(s):  
W.D. Harrison ◽  
C.F. Raymond
Keyword(s):  
Carbon Dioxide ◽  
Grain Size ◽  
Pure Water ◽  
Impurity Content ◽  
Boundary Area ◽  
Total Impurity ◽  
Polycrystalline Ice ◽  
Glacier Ice ◽  
Total Impurity Content

AbstractTotal impurity content of salt plus carbon dioxide was estimated as a function of grain size and depth in polycrystalline ice samples cored from a temperate glacier by measuring the electrical conductivity of the melt with air excluded. Conductivity decreased with increasing depth and grain size and ranged from × 10-5 to 0.4 × 10-5 Ω -1 m-1 at 0°C. The conductivity of pure water at 0°C is 0.1 × 10-5 Ω -1 m-1 Studies of the configuration of the three phases and of in situ temperature were also made. Thermodynamic constraints indicate that these impurities are probably concentrated as follows: about 5 mol m-3 in the liquid in the veins along three-grain intersections, roughly 1 × 10-6 mol m-2 associated with grain-boundary area exclusive of veins, and about 0.7 × 10-3 mol m-3 in volume exclusive of veins and grain boundaries. The last of these categories seems to account for most of the impurities in coarse ice (grain size about 20 mm), but all three categories seem significant in fine ice (grain size about 2 mm). Differences in bulk impurity content possibly indicate different histories of flushing by water.

scholarly journals Impurities and their Distribution in Temperate Glacier Ice

1976 ◽  
Vol 16 (74) ◽  
pp. 173-181 ◽  
Author(s):  
W.D. Harrison ◽  
C.F. Raymond
Keyword(s):  
Carbon Dioxide ◽  
Grain Size ◽  
Pure Water ◽  
Impurity Content ◽  
Boundary Area ◽  
Total Impurity ◽  
Polycrystalline Ice ◽  
Glacier Ice ◽  
Total Impurity Content

AbstractTotal impurity content of salt plus carbon dioxide was estimated as a function of grain size and depth in polycrystalline ice samples cored from a temperate glacier by measuring the electrical conductivity of the melt with air excluded. Conductivity decreased with increasing depth and grain size and ranged from × 10-5to 0.4 × 10-5Ω-1m-1at 0°C. The conductivity of pure water at 0°C is 0.1 × 10-5Ω-1m-1Studies of the configuration of the three phases and ofin situtemperature were also made. Thermodynamic constraints indicate that these impurities are probably concentrated as follows: about 5 mol m-3in the liquid in the veins along three-grain intersections, roughly 1 × 10-6mol m-2associated with grain-boundary area exclusive of veins, and about 0.7 × 10-3mol m-3in volume exclusive of veins and grain boundaries. The last of these categories seems to account for most of the impurities in coarse ice (grain size about 20 mm), but all three categories seem significant in fine ice (grain size about 2 mm). Differences in bulk impurity content possibly indicate different histories of flushing by water.

Dislocation resistivity in Cu: dependence of the deviations from Matthiessen's rule on temperature, dislocation density and impurity content

1995 ◽  
Vol 7 (18) ◽  
pp. 3515-3528 ◽  
Author(s):  
R Zurcher ◽  
M Muller ◽  
F Sachslehner ◽  
V Groger ◽  
M Zehetbauer
Keyword(s):  
Dislocation Density ◽  
Impurity Content ◽  
Matthiessen's Rule ◽  
Matthiessen’S Rule

The electronic band structure of silicon

Physica ◽  
1954 ◽  
Vol 3 (7-12) ◽  
pp. 967-970
Author(s):  
D JENKINS
Keyword(s):  
Band Structure ◽  
Electronic Band Structure ◽  
Electronic Band

Matthiessen's rule

AccessScience ◽  
2015 ◽  
Keyword(s):  
Matthiessen's Rule ◽  
Matthiessen’S Rule

RELATIVISTIC ELECTRONIC BAND STRUCTURE OF THE HEAVY METALS AND THEIR INTERMETALLIC COMPOUNDS

1972 ◽  
Vol 33 (C3) ◽  
pp. C3-57-C3-72 ◽  
Author(s):  
A. J. FREEMAN ◽  
D. D. KOELLING
Keyword(s):  
Heavy Metals ◽  
Band Structure ◽  
Intermetallic Compounds ◽  
Electronic Band Structure ◽  
Electronic Band

THE ELECTRONIC BAND STRUCTURE OF V3Ga AND V3Si

1972 ◽  
Vol 33 (C3) ◽  
pp. C3-223-C3-233 ◽  
Author(s):  
I. B. GOLDBERG ◽  
M. WEGER
Keyword(s):  
Band Structure ◽  
Electronic Band Structure ◽  
Electronic Band
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