HOW TO SELECT A THIN-FILM SAMPLE SUPPORT WINDOW MATERIAL
Selection of a suitable thin-film sample support material is principally based on serving two requirements: the degree of effectiveness in passing radiation and resistance to chemical attack by the sample especially in liquid state. Additional concerns are sample retention strength, applications in evacuated or pressurized conditions, integration time, excitation potential and related heat generation.

1. TRANSMITTANCE OF SPECTRAL LINES
The transmittance properties of a thin-film are functions of gauge thickness, density and mass attenuation coefficients of the constituent chemical elements

The following graphic is the most frequently used visual aid in comparing % Transmittance values of various thin-film substances and gauges. Simply refer the spectral line of the element in the sample of analytical interest having the lowest energy, KeV, (or shortest wavelength, Ångstrom) to each of the curves representing thin-film materials and gauges. Compare their transmittance percentages and select the thin-film offering the highest % Transmittance value.

2. CHEMICAL RESISTANCE
In conjunction with selecting a thin-film providing a high % Transmittance value, evaluate the resistance of a thin-film sample support substance to chemical attack by a sample material from the following table.
Liquid sample substances are more prone to degrading a thin-film than solids.

SPECTROMEMBRANE® THIN-FILM SAMPLE SUPPORT CARRIER FRAMES
SpectroMembrane® Thin-Film Sample Support Carrier Frames consist of a thin-film sample support substance attached to a frame that serves as a carrier. In affixing a thin-film substance to an XRF Sample Cup, the thinfilm material is not directly handled; contamination possibility is completely eliminated. Nearing or at the completion of attachment, the thin-film automatically detaches from the carrier frame leaving a taut wrinkle-free sample support.

NO WASTE – NO STATIC CLING – NO CONTAMINATION – NO EXPERIENCE NECESSARY

Step 1.
Place SpectroMembrane® Over XRF Sample Cup

Step 2.
Press Snap-On Ring or Sleeve over SpectroMembrane® and tear away Carrier Frame

SpectroMembrane® is packaged 100 units per package to match the same packaging as 100 XRF Sample Cup Sets per package. When ordering sample cups, simply order the same number of SpectroMembrane packages.

THIN-FILM SAMPLE SUPPORT WINDOWS IN CONTINUOUS ROLLS AND PRECUT CIRCLES
Thin-Film Sample Supports are available in Continuous Rolls and Pre-Cut Circles.
Fabrication of all thin-films is performed under environmentally controlled conditions to avoid the potential possibility of inadvertently
introducing trace levels of contaminates and individually shrink-wrapped to preserve the original integrity..

MICROPOROUS POLYPROPYLENE FILM
Microporous Film is a gas permeable thin membrane used in conjunction with Series 1500 XRF Sample Cups to establish pressure equalization in inert gas and vacuum environmental analytical conditions.
When Microporous Film is attached to the flanged open end of a Series 1500 XRF Sample Cup, the tortuous pore channels permit gaseous elements to penetrate. The pore size prohibits crystalline particles to pass. Any entrapped gas or air within the sealed sample cup is evacuated leaving the thin-film sample support substance on the opposite end flat and free of convolutions or distension attributed to pressure differentials. Use the optionally available Palm Held or Snap-On Ring Fastener.

..

.

. Scarica il capitolo della brochure Chemplex relativo alle pellicole XRF