It even results in geologic hazard;for the mine geologic hazard,the background of physiognomy is the potential factor,while the irrational exploitation is the magistral factor.
I will not dwell on, nor mourn over, our untimely decay, nor reproach my paleface brothers with hastening it as we too may have been somewhat to blame.
For the reason why optical activity of mesomer is counteracted classical answer was not convincing. By use of the helix theory and stable staggered conformation answer can be obtained.