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1.Tedpella Carbon Graphite Rods
2.Tedpella Carbon Graphite Rods 61-15
3.Tedpella Carbon Graphite Rods 61-15
4.Tedpella Carbon Graphite Rods-
61-15
12/
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Carbon Products
Carbon: Introduction
with permission, based on Ian M. Watts book1 and article4
1.Deity: 2.2gm cm-3
2.Melting Point: around 3550C
3.Evaporation Temp.: 2400C
4.Temperature at which a substance has a vapor pressure of 1.33 x 10-2 mbar (arbitrary)
Average Thickness: 23nm at 5?g cm-2 in nm
Uses:
1.TEM substrates, replicas
2.SEM coating of non-conducting samples for x-ray analysis
3.EBSD: coating of non-conducting samples with an amorphous layer
4.Microprobe: coating of non-conducting samples with highly conductive layer
Carbon films are uniformly amorphous and highly traparent to electro because carbon has a low atomic weight. Due to their strongly interconnected three-dimeional network structure, carbon films have remarkable mechanical stability, even when as thin as 1 - 2nm3.
At thicknesses used in electron microscopy from about 2nm upwards carbon films are chemically inert, continuous and basically free from self-structure except for a speckled appearance visible at only the highest magnificatio.
Carbon depositio produce a film around the sides and back of specime without specimen rotation (see EM picture to left). This may be explained by the deflection of light carbon atoms out of straight-line flight by collisio with gas molecules and with the walls or obstructio in a vacuum chamber.
References:
1. Watt IM, 1985. The principles and practice of electron microscopy. Cambridge Univeity Press, ISBN 0-521-25557-0.
2. Bradley DE, 1954. Evaporated carbon films for use in electron microscopy. Br J Appl Phys, 5, 65-66.
3. Hayat MA, 1981. Principles and techniques of electron microscopy, Vol 1 (2nd Ed), Univeity Park Press.
4. Watt IM, November, 1991. Carbon - The electron microscopists most useful element. Microscopy and Analysis, pp 21-23.
Carbon Rods
The carbon rods are offered in either spectroscopically pure or technical grades for standard electron microscopy evaporation requirements using carbon coate. Due to the purification process used all carbon rods we supply have a graphite structure. The purification process removes impurities at a high temperature and causes the carbon to crystallize. The graphite structure has no advee effects on the carbon coating or the carbon coating process. The user might perceive an additional advantage: the carbon rods (graphite rods) are less brittle than the carbon rods and are easier to handle and easier to shape.
Technical grade carbon rods have a typical impurity level of around 50ppm or greater. Typical applicatio are non critical SEM or SEM/EDS coating of non-conducting samples.
"Spec-Pure" (spectroscopically pure) grade is available for carbon (graphite) rods with impurities equal or less than 2ppm (single element 1 ppm or less). Typically the impurity level is more likely 1ppm or less. This grade should be used for TEM, FESEM, FIB, WDS, EBSD, Microprobe and more critical SEM/EDS applicatio.
1.Grade 1 Spec-Pure Carbon Rods
Spectroscopically pure graphite structure carbon rods with an impurity level of 2ppm or less with 1ppm as maximum level for each element. The rods are all 12" long with three nominal diamete (1/8", 3/16" and 1/4") to comply with the carbon source used in different high vacuum carbon evaporato. Highly recommended for TEM, FESEM, FIB, WDS, EBSD, Microprobe and more critical SEM/EDS applicatio.
Prod #
Description
Unit
61-15
Carbon Rods, Grade 1 Spec-Pure, 1/8" x 12" (3 x 304mm)
pkg/12
61-25
Carbon Rods, Grade 1 Spec-Pure, 3/16" x 12" (4.6 x304mm)
pkg/12
61-35
Carbon Rods, Grade 1 Spec-Pure, 1/4" x 12" (6.2 x 304mm)
pkg/12
2.Grade 2 Carbon Rods, Technical Grade
Technical grade graphite structure carbon rods contain impurities typically equal to or less than 50ppm. However, as an exception some batches can contain impurities up to 200 ppm. The impurities typically coist of: (ppm max.): Ca 20, Fe 20, Cr 10, Si 2-5, Ti 8-10, V 4-4 and traces of other elements. Use this grade for non-critical SEM and SEM/EDS applicatio.
Prod #
Description
Unit
61-52
Carbon Rods, Technical Grade, Grade 2, 1/8" x 12" (3 x 304mm)
pkg/12
61-62
Carbon Rods, Technical Grade, Grade 2, 3/16" x 12" (4.6 x304mm)
pkg/12
61-72
Carbon Rods, Technical Grade, Grade 2, 1/4" x 12" (6.2 x304mm)
pkg/12
:
http://www.sangerbio.com/
Sanger Biotech.---
OmniprobetedpellaEMS
Sanger Biotech.---
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