| Id |
Subject |
Object |
Predicate |
Lexical cue |
| T294 |
0-148 |
Sentence |
denotes |
Filter media, such as those used in N95 masks and in mechanical ventilation systems, consist of myriad interwoven fibers through which air is moved. |
| T295 |
149-218 |
Sentence |
denotes |
Their purpose is to arrest particles as they move through the matrix. |
| T296 |
219-313 |
Sentence |
denotes |
Filters capture particles chiefly by three mechanisms: impaction, interception, and diffusion. |
| T297 |
314-536 |
Sentence |
denotes |
Impaction occurs when the momentum of a particle propelled toward a filter fiber prevents the particle from diverging around the fiber along the flow lines of the air stream, causing the particle to collide with the fiber. |
| T298 |
537-639 |
Sentence |
denotes |
Impaction is the primary mechanism responsible for removing particles greater than 500 nm in diameter. |
| T299 |
640-900 |
Sentence |
denotes |
Interception occurs when a particle diverges around a fiber along the flow lines of the airstream, the distance between the vector of the airstream and the centroid of the particle is smaller than the radius of the particle, and the particle touches the fiber. |
| T300 |
901-980 |
Sentence |
denotes |
Interception operates efficiently on particles greater than 200 nm in diameter. |
| T301 |
981-1149 |
Sentence |
denotes |
Diffusion is the final important mechanism of particle removal, and it is most effective at removing very fine particles less than 200 nm, especially at low flow rates. |
| T302 |
1150-1330 |
Sentence |
denotes |
Particles around 300 nm in diameter are least subject to these three removal mechanisms, and they are considered the “most penetrating” particles for a majority of filter types.204 |
