the resulting white powder is the mesoporous material as prepared deionized water alcohol hydrochloric acid are taken by volume of 1000 1750 920 ml to prepare the solvent tetraethyl orthosilicate dodecyltrimethoxysilane and peregal o25 are weighed in the following amounts u2014 7 grams 8 6 grams 6 grams respectively mixed and added to the solvent and stirred continuously for 48 hours then aged for 48 hours under rt filtered with a filter paper and then dried under rt for 48 hours the dried product is transferred to a crucible and then put into a muffle furnace ramped in temperature at 3 u00b0 c min and maintained at a temperature of 600 u00b0 c for 8 hours after natural cooling the resulting white powder is the mesoporous material as prepared deionized water alcohol ammonia water are taken by volume of 700 1250 215 ml to prepare the solvent tetraethyl orthosilicate octadecyltrimethoxysilane and peregal o16 are weighed in the following amounts u2014 7 grams 10 grams 6 grams respectively mixed and added to the solvent and stirred continuously for 48 hours then aged for 48 hours under rt filtered with a filter paper and then dried under rt for 48 hours the grinded white powder is the silicon dioxide material with a long chain alkyl and with a microporous structure as prepared this example is based on the method of example 1 2 or 3 except that the solvent in the raw material is added in advance into 30 ml nanometer ferroferric oxide magnetic fluid which has been subject to dispersion treatment and has a concentration of 30 milligram ml by calcining in the muffle furnace and reducing by hydrogen at 600 u00b0 c for 10.