As per the Duskblade's description of the "Arcane Channelling" ability:
Arcane Channeling (Su):
Beginning at 3rd level, you can use a standard action to cast any touch spell you know and deliver the spell through your weapon with a melee attack[...]
(emphasis mine)
For spells the character
doesn't know, this is a definite "no". However, for scroll/wand spells that are also in the character's spell known list, i believe this would be possible.
I'm not sure how the item activation rules apply on this, but you're not simply casting a spell, so it probably causes AoOs.
Also, in the case of scrolls, you still need a free hand to provide the somatic/material components for the spell completion. Unless it's a spell w/o somatic/material components, it could be hard to do with a weapon in hand (there are some feats for that).