Table of contents 1 Why is particle size important?
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- INTRODUCTION
| RANGE IN MICRONS
10nm - 5,000 (5mm) OPTIMAL APPLICATIONS POWDERS, SUSPENSIONS, AND EMULSIONS WEIGHT 56kG (123 lbs) FOOTPRINT WIDTH 705mm (28”) DEPTH 565mm (22”) HEIGHT 500mm (20”) The LA-960 combines the most popular modern sizing technique with state of the art refinements to measure wet and dry samples measuring 10 nanometers to 5 millimeters. The central idea in laser diffraction is that a particle will scatter light at an angle determined by that particle’s size. Larger particles will scatter at small angles and smaller particles scatter at wide angles. A collection of particles will produce a pattern of scattered light defined by intensity and angle that can be transformed into a particle size distribution result. INTRODUCTION The knowledge that particles scatter light is not new. Rayleigh scattering of light from particles in the atmosphere is what gives the sky a blue color and makes sunsets yellow, orange, and red. Light interacts with particles in any of four ways: diffraction, reflection, absorption, and refraction. Figure 17 shows the idealized edge diffraction of an incident plane wave on a spherical particle. Scientists discovered more than a century ago that light scattered differently off of differently sized objects. Only the relatively recent past, however, has seen the science of particle size analysis embrace light scattering as not only a viable technique, but the backbone of modern sizing. Bench-top laser diffraction instruments became practical with the advent of high intensity, reasonably priced lasers and sufficient computing power to process the scattered light data. Once these barriers to market entry were eliminated the advantages of laser diffraction over other techniques were apparent: speed of analysis, application flexibility, small tải về 7.54 Mb. Chia sẻ với bạn bè của bạn:
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