Abstract: A holder, e.g., for rolls of paper is configured such as to dispense a paper web from the holder via a web braking element (14, 15, 17), which may have alternative forms. The web braking (14, 15, 17) prevents paper from being dispensed uncontrollably from the holder as a result of inertia forces or some other circumstance. The holder is comprised preferably of two major parts, namely a back plate (1) and a causing (2), which houses the roll (4) and roll support means (8, 9). When the roll (4) is placed horizontally in the casing the roll is supported on two shafts (8). When the roll extends vertically in the casing, it is supported by a shelf (9). The shelf has formed therein an aperture (10) through which the paper web passes.

Abstract: Use of oxygen, oxygen containing gases or substances giving off oxygen in reduction or inhibition of the dark coloring of pulp or paper in white water systems, especially closed ones, in production of pulp and paper, these substances being added to the white water system in such an amount that aerobic conditions are maintained substantially permanently in at least a part of the white water system, i.e. the redox potential is higher than -100 mV.