CANALC0 ANALYZERS
EDITOR'S C O L U M N
TAKE THE LABOR OUT OF LABORATORY
Visual Inspection 10. Circles from each box of the sample shall be inspected visually for compliance with Section 3. TABLE I .
GENERAL
BEQTJIREMENTS
Property
Require ment
Alpha-cellulose content, min per cent Copper number," max p H value
95 0.5 3.0 to 8.0
IN MICRO-CHEMISTRY the new
" The requirement for copper number is not applicable to class D filter paper.
Ultra-Microspectrophotometer Ultra-Microspectrophotometer gives fully automated quantitation, in both the visible and the U.V. for
TABLE I I . — A S H CONTENT
Maximum Average Ash Con tent per Circle, mg. Type I I Type I Diameter Classes Class Classes cm.' 5.5 7.0 9.0 11.0 12.5 15.0 18.5
Class
A,B,C
D
E,F,G
H
0.25 0.41 0.07 1.00 1.29 1.86 2.83
0.31 0.51 0.84 1.25 1.62 2.33 3.54
0.025 0.041 0.067 0.100 0.129 0.186 0.283
0.020 0.033 0.054 0.080 0.103 0.149 0.226
• •
cell components tissue extracts
• • • • •
fluorescence micro-liquids (10-50 ul) interference microscopy autoradiographs micro-chromatography (10 ul flow cuvettes)
Two Models
" The ash content of larger sizes shall be in proportion to the area of the circle.
1. Digital Ratio Reporter, for one and two wavelength analysis 2. Absorption Curve Computer, f o i spectral curve recording
TABLE I I I . W E T BURSTING STRENGTH, T I M E OF FLOW OF WATER, AND RETENTION OF PRECIPITATES
Average Average Wet Time of Bursting Flow of Retention of Strength, Water, Precipitates— min., max., Filtrate Class points 4 sec. clear from: A
3.0
20
Β C D Ε
3.5 4.0 45.0 3.0
40 150 300 20
F G H
3 5 4.0 4.0
40 150 150
Ferric hy droxide Lead sulfate Barium sulfate Barium sulfate Ferric hy droxide Lead sulfate Barium sulfate Barium sulfate
1)981-56, concerning testing of a n a lytical filter papers, covers t h e follow ing p o i n t s : sampling, thickness, a p p a r e n t density, p H value, alpha cellu lose, a n d copper n u m b e r . A p p a r a t u s , reagents, a n d procedures are outlined for determining retention of precipitates, time of water flow, a s h , a n d wet b u r s t i n g s t r e n g t h . 1
Under the standard procedure of the Society, these specifications are under the jurisdiction of the A.S.T.M. Committee D-6 on Paper and Paper Products. "Prior to adoption as standard, these specifications were published as tentative from 1950 to 1952. ''See p . 209. 4 Average W e t Bursting Strength for Class F was editorially changed in July, 1953.
