Deviations from Matthiessen's rule in continuous metal films

High magnification imaging of macromolecules on metal coated biological specimens is limited only by wet preparation procedures since recently obtained instrumental resolution allows visualization of topographic structures as smal l as 1-2 nm. Details of such dimensions may be visualized if continuous metal films with a thickness of 2 nm or less are applied. Such thin films give sufficient contrast in TEM as well as in SEM (SE-I image mode). The requisite increase in electrical conductivity for SEM of biological specimens is achieved through the use of ligand mediated wet osmiuum impregnation of the specimen before critical point (CP) drying. A commonly used ligand is thiocarbohvdrazide (TCH), first introduced to TEM for en block staining of lipids and glvcomacromolecules with osmium black. Now TCH is also used for SEM. However, after ligand mediated osinification nonspecific osmium black precipitates were often found obscuring surface details with large diffuse aggregates or with dense particular deposits, 2-20 nm in size. Thus, only low magnification work was considered possible after TCH appl ication.

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Matthiessen's rule

AccessScience ◽

10.1036/1097-8542.410800 ◽

2015 ◽

Keyword(s):

Matthiessen's Rule ◽

Matthiessen’S Rule

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The resistivity, temperature coefficient of resistivity and thermoelectric power of thin continuous metal films II: A methodology for computer processing of thin film data to extract parameters with associated error estimates

Thin Solid Films ◽

10.1016/0040-6090(87)90087-3 ◽

1987 ◽

Vol 150 (2-3) ◽

pp. 163-174 ◽

Cited By ~ 8

Author(s):

J.B. Thompson

Keyword(s):

Thin Film ◽

Temperature Coefficient ◽

Thermoelectric Power ◽

Error Estimates ◽

Metal Films ◽

Computer Processing ◽

Temperature Coefficient Of Resistivity ◽

Continuous Metal

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Validity of Matthiessen's Rule for Cold-worked Wires

Australian Journal of Physics ◽

10.1071/ph530116 ◽

1953 ◽

Vol 6 (1) ◽

pp. 116 ◽

Cited By ~ 13

Author(s):

W Boas ◽

JF Nicholas

Keyword(s):

Electrical Resistivity ◽

Characteristic Temperature ◽

Wire Drawing ◽

Metals And Alloys ◽

Nickel Copper ◽

Aluminium Bronze ◽

Cold Worked ◽

Matthiessen's Rule ◽

Matthiessen’S Rule

Matthiessen's rule has been tested by, determining the slopes of the electrical resistivity-temperature curves for wires of eight common metals and alloys in various states of deformation by wire-drawing. The results show that the slope is independent of deformation, i.e. the rule is true, to within 0�5 per cent. for nickel, copper (two purities), iron, and 80/20 brass, and to within 1 per cent. for aluminium. However, for 75/25 brass and an aluminium bronze, deformations corresponding to logarithmic strains of 2�3 decrease the slopes by 1 and 3 per cent. respectively. As an explanation of this behaviour, it is suggested that deformation causes an increase in the characteristic temperature.

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