Showing results: 46 - 47 of 47 items found.
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3938 -
TSI Inc.
TSI''s newest Scanning Mobility Particle Sizer SMPS™ spectrometer is widely used as the standard for measuring airborne particle size distributions. This system is also routinely used to make accurate nanoparticle size measurements of particles suspended in liquids. The National Institute of Standards and Technology (NIST) uses a TSI DMA to size 60 nm and 100 nm standard size reference materials. SMPS spectrometer sizing is a discreet technique in which number concentrations are measured directly without assuming the shape of the particle size distribution. The method is independent of the refractive index of the particle or fluid, and has a high degree of absolute sizing accuracy and measurement repeatability. TSI''s Model 3938 is the 3rd generation of SMP, trusted by researchers for over 30 years.
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Torontech Group
Optical fiber consists of a core and a cladding layer, selected for total internal reflection due to the difference in the refractive index between the two. In practical fibers, the cladding is usually coated with a layer of acrylate polymer or polyimide. This coating protects the fiber from damage but does not contribute to its optical waveguide properties. Individual coated fibers then have a tough resin buffer layer and/or core tube(s) extruded around them to form the cable core. Several layers of protective sheathing, depending on the application, are added to form the cable. Rigid fiber assemblies sometimes put light-absorbing ("dark") glass between the fibers, to prevent light that leaks out of one fiber from entering another. This reduces cross-talk between the fibers, or reduces flare in fiber bundle imaging applications Optical fibers are very strong, but the strength is drastically reduced by unavoidable microscopic surface flaws inherent in the manufacturing process. The initial fiber strength, as well as its change with time, must be considered relative to the stress imposed on the fiber during handling, cabling, and installation for a given set of environmental conditions. There are three basic scenarios that can lead to strength degradation and failure by inducing flaw growth: dynamic fatigue, static fatigues, and zero-stress aging.
