no knudsen diffusional flow component the flow in the filters made in examples i and ii are deemed also to be poiseuille since the pore sizes in those filters are either the same size or larger than the pore size of the coating in example iii fig3 a shows the highly porous nature of the starting carbon fiber paper the uncoated paper is extremely porous with pores as large as 100 u03bcm fig3 b shows the excellent filtration surface provided by the tio 2 after coating example iii the coated paper has the surface pores filled in with tio 2 and provides an excellent filtering surface having much smaller pores fig4 shows that the coating applied to the carbon fiber paper remains at the surface of the paper and does not penetrate into the bulk of the paper example i the method of the present invention can be used to make u201c absolute u201d filters for gas filtration the method of the present invention is a simple dry process and requires no solvents during the coating process filters made by the method of the present invention can be used for high temperature situations above 400 u00b0 c or for highly corrosive environments filters for corrosive gases such as those used in semiconductor manufacture and filters for high temperature gases can be made using the method of the present invention sic or tic as the powder on graphite or sic substrate can be used for gas filtration at temperatures ranging up.