You're mixing object files compiled with VS 2008 and VS 2010. This is forbidden when using the C++ Standard Library. (Unfortunately, we can't emit a nice linker error in this scenario, although we will when mixing 2010 and post-2010.)
The symptom is the linker error complaining about std::basic_string and __declspec(dllimport). In VS 2010, std::basic_string isn't marked __declspec(dllimport) anymore. Therefore, if the linker is complaining like this, you're picking up VS 2008's headers somehow (whether in this compilation, or with a separately compiled object file). You can compile with /showIncludes to see what headers are getting dragged in. Since Acquisition_Imaging.obj is looking for __declspec(dllimport) std::basic_string, it's almost certainly one of the offending object files.