Underflow thickening, centrifugal cleaning

theory 584–585

Unidirectional longitudinal diffusion, residual

Sodium fractions 139

United States

– legislation 1195–1198

– recovered paper grades 1162

UP see unbleached pulp

upflow reactors, atmospheric 623–624

Upper cooking circulation 388

Urban forest 1151

uronic acids, determination 1233–1234

Utilization, packaging materials 1193

Utilization rate 1167

UV microscopy, fiber morphology 1271

v

Va-Purge process 130

Vacuum swing adsorption 828

Validation, selected model of kraft cooking

kinetics 223–227

Valley beater, pulp beating 1281

Valmet PGW grinder 1095

Valonia ventricosa 24

Van Heiningen model 689

– theoretical base 690–701

Vanillin

– chlorine bleaching 747

– structure 308

Vanillyl alcohol

– chlorine bleaching 747

– model reaction with thiosulfate 424

vapor recompression 979–980

Vascular cells, cell components 46

Velocity

– aperture/passing 565

– rotor tip (screening operating parameters)

Velocity profile, hydrocyclone 581

Veratryl-b-guaiacyl ether, homolytic

Fragmentation and oxidation 751

Veratrylglycerol-b-guaiacyl ether 749

Vessels

– cell components 46

– hardwoods 53

– rattan 50

– wood cells 50

Vibrating conveyor, log handling 98

Vibratory screens 605

Vilamo method 403

Vinyl ether

– resistance to chlorine dioxide oxidation

– structure and relative oxygen susceptibility

Virgin paper, annual flow in comparison to

Recovered paper 15