Content Feed-
Calculating microspheres per gram
During scientific experiment design and analysis it is common to need to know the number of spheres per gram of dry material. We have put together the table below to help speed up the process.
If you have material of a density different from those listed in the table, divide the number of spheres per gram in the density ~1.0 g/cc column by the true particle density of your material to get an estimate of the number of spheres per gram.
Product Size Polyethylene
Density ~1.0 (g/cc)Soda Lime Glass
Density ~2.5 (g/cc)Lower (um) Upper (um) Spheres per Gram Spheres Per Gram 20 27 147,162,715 58,630,564 27 32 74,393,558 29,638,868 32 45 33,467,185 13,333,540 45 53 16,233,536 6,467,544 53 63 9,788,528 3,899,812 63 75 5,813,720 2,316,223 75 90 3,401,258 1,355,083 90 106 2,029,192 808,443 106 125 1,239,525 493,835 125 150 734,672 292,698 150 180 425,157 169,385 180 212 253,649 101,055 212 250 154,941 61,729 250 300 91,834 36,587 300 355 54,371 21,662 355 425 32,196 12,827 425 500 19,305 7,691 500 600 11,479 4,573 600 710 6,796 2,708 710 850 4,025 1,603 850 1000 2,413 961 1180 1400 890 354 1400 1700 513 204 1700 2000 302 120 2000 2360 184 73 2360 2800 111 44 2800 3350 66 26 Note: This table assumes the mean diameter is half way between the upper and lower size.
-
Phosphorescent Microspheres – Long Afterglow Particles
Phosphorecent Beads - Yellow Green Afterglow
Phosphorescent microspheres in particle sizes 10 to 600 microns are now available from Cospheric LLC. These phosphorescent particles are 90% spherical and appear to be off-white under ordinary daylight or regular room illumination. However, when the lights are turned off these phosphorescent particles exhibit phosphorescent yellow-green after-glow.
The spheres have tight particle size distributions and are > 90% within size range. Polymer spheres that incorporate proprietary phosphorescent ingredient have a melting point of 115°C , and are mechanically stable past 90°C. Phosphorescent beads are also inert in most solvents.
Intensity of Phosphorescent Afterglow:
Intensity according to DIN 67510-1800 mcd/m2 at 1 minute
180 mcd/m2 at 5 minutes
90 mcd/m2 at 10 minutes
12 mcd/m2 at 1 hour
5 mcd/m2 at 2 hoursExcitation and Phosphorescent Emission Curve:
