N(.beta.-chloro-propionyl or acryloyl)carbamyl or ureido piperaz
N-alkoxyethoxyethylphenylenediamine color developing agents
Natural gas dehydration apparatus
Negative ion generator
Negative working photoresist material comprising a N-vinyl monom
Negligible pressure drop absorber
Nested diffusional filter
Nitrated polyimide gas separation membranes
Nitrogen containing polymers aelements
Nitrogen purification device
Nitrogen-selective zeolitic adsorbent for use in air separation
Nitroso-dimer-containing compositions and photoimaging process
No glasses 3-D viewer
Noble gas purifier with single purifier vessel and recuperative
Noble metal image forming method
Non-particulating compact adsorbent filter
Non-planar microfabricated gas chromatography column
Non-silver halide light-sensitive material sensitized by colloid
Non-silver salt type photosensitive composition
Nonparticulating adsorbent recirculating filter