Abstract: An apparatus for determining the effect of dilution and/or diffusion of the gaseous components of a gas flow passing through a gas permeable test object is claimed. The apparatus comprises a source of calibrating gas, a laminar resistance coupled to the source of calibrating gas with the gas flowing through the laminar resistance, and a volumeter is coupled to the laminar resistance for measuring the volume of gas flowing therethrough. The gas from the laminar resistance flows through the test object to a gas concentration measuring device for receiving and for measuring the concentration thereof. A bypass device is provided for bypassing the flow of gas around the test object, and a suction device draws gas from the source to the measuring device.

Abstract: An apparatus is provided for determining the burning and/or glowing rate of a smokable article. The apparatus comprises a sensor for sensing the incandescent zone of the smokable article and a drive apparatus for moving the sensor along a path parallel to the direction of burning and glowing of the smokable article.

Abstract: A method for the treatment of tobacco stems which comprises providing the tobacco stems in the uncut condition with a moisture content ranging from 15 to 70% relative to the dry weight of the tobacco stems, performing at least one first cut of said tobacco stems in a direction parallel to the longitudinal axis thereof, conditioning the resultingly cut tobacco stems, and performing more than one second cut of said tobacco stems in a direction parallel to said longitudinal axis, wherein the respective longitudinal planes containing said first and said second cuts reside in substantially perpendicular relation to each other. The resulting tobacco stem sections exhibit improved uniformity of length and thickness, and minimal fiber destruction, and have improved expansion capacity.

Abstract: An improved fibrous filter is disclosed which is useful for removing harmful chemicals from tobacco smoke. This filter is characterized as containing at least one compound selected from the group consisting of ##STR1## wherein R represents a straight-chain, branched or cyclic aliphatic hydrocarbon radical.

Abstract: A method for the catalytic removal of nitric oxide and carbon monoxide from tobacco smoke which comprises contacting the smoke with a compound of the formulaM.sub.2 M'RuO.sub.6wherein M is a divalent metal, M' is a trivalent rare earth metal, and Ru has a valence of 5, M and M' being such that their ions are capable of forming a perovskite lattice with the Ru ions. The catalyst can be mixed with tobacco, or incorporated into the cigarette paper or filter. Optionally, suitable inorganic or organic adsorbing materials are desirable; e.g. carbon and calcium carbonate.