3 except that the porous structures were flipped part way through the process in order to obtain a more uniform final density distribution temperature of the gas stream was approximately 1740 u00b0 f when measured by a temperature sensor such as temperature sensor 74 of fig1 the test conditions and data from this example are presented in table 4 the carbon matrix deposited within disks a and c was all rough laminar before the flip and essentially smooth laminar after the flip the microstructure of disk b was not determined the final densified porous structures had density profiles similar to fig9 table 4______________________________________ cum gas flow part density time rate temp gaindisk hour sccm f u00b0 g cc ______________________________________a 72 4000 1859 0 743 flip 96 4000 1859 0 853 111 4000 1855 1 034b 49 4000 1854 0 619 flip 74 4000 1849 0 898c 49 4000 1858 0 625 flip 75 4000 1853 0 915______________________________________ two annular porous structures prepared from a fibrous textile structure and having the same dimensions as described in example 1 were simultaneously densified by a pressure gradient cvi cvd process with a fixture similar to fixture 6 of fig4 having all 34 id 34 spacers and the reactant gas mixture of example 1 temperature of the gas stream was estimated 1745 u00b0 f when measured by a temperature sensor such as temperature sensor 74 of fig1 the test conditions and data from this example are presented in table 5 density gain on table 5 is an average for the two disks the carbon matrix deposited within the densified porous structure at the end of the process comprised all rough laminar microstructure computed tomagraphy scans of the disk demonstrated density profiles similar to.