Description
EPR Tube
Product numbers that include "PQ" belong to our Precision Tube
Family. Those with "SQ" are our Economy brand tubes. Precision
brand EPR tubes hold 10-15 times tighter tolerance on the inner
diameter, and >5 times smaller camber and concentricity over
Economy Brand tube. Precision tubes are recommended for
cw-experiments that require a constant filling factor or
reproducibility on sample volume in the cavity.
Clear Fused Quartz (CFQ) is purified from naturally occurring
quartz so the existence of certain material radicals from mining
is inevitable. Due to technological advancements the sensitivity
of EPR has gradually increased. The direct result is that certain
high Q cavities will pick up the signal from these impurities,
especially in tubes of over 4 mm OD. In this case we recommend
switching to Suprasil® EPR products which are made of
synthetic material and suppress major impurity contents shown in
Table 1 by the average of 2 orders of magnitude. Impurity analysis
test results for Suprasil® are shown below:Chemical impurity
analysis results for CFQ are shown below:
Table 1: Impurity Analysis for
Clear Fused Quartz (unit: ppm in weight)
| 15 |
0.5 |
<0.05 |
<0.05 |
0.1 |
0.4 |
0.6 |
0.05 |
<0.05 |
0.3 |
1.1 |
0.7 |
Table 2: Impurity Analysis for
Suprasil Quartz (unit: ppm in weight)
| <0.05 |
<0.05 |
<0.05 |
<0.05 |
<0.05 |
<0.05 |
<0.05 |
<0.05 |
<0.05 |
<0.05 |
<0.05 |
<0.05 |
For photochemistry studies, the cut-off wavelength is 265 nm for CFQ
and 190 nm for Suprasil.
| Properties | |
| Tube Length (mm):
| 159 |
| Wall Thickness (mm):
| 0.48 |
| Concentricity/Camber (microns):
| 76 / 76 |
| Tube OD (mm):
| 2.97 +/- 0.013 |
| Tube ID (mm):
| 1.99 +/- 0.013 |
Save Time Heat-Sealing EPR Samples!
Heat-sealing quartz tubes is difficult enough so we've provided an easier way. By ordering our constricted tube you'll seal EPR tubes more quickly, with less effort. Choose your tube, add the suffix "CONS" to the product number and remember to order 1 inch longer than required.