Those look like the simpson structural hangers to me. They have a top flange and flange on the other side to lay on top of and straddle a beam. They are typically used to support joists off of an LVL, etc. I have a few left over from a job in my garage.
The hangers are probably sufficient to handle the joist load. I have to agree with Scott that the real questions is 'attachment'. I doubt they are properly attached to the wall. There aren't any anchors showing on the face and they don't have any holes on the top flange (unless field drilled). Just laying on the wall isn't going to cut it.

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