1 Due to the high degree of regio-and stereoselectivity (due to the concerted mechanism), the Diels-Alder reaction is a very powerful reaction and is widely used in synthetic organic chemistry.2  The reaction usually thermodynamically favourable due to the conversion of 2 &#960 -bonds into 2 new stronger &#963-bonds. Due to the high degree of regio-and stereoselectivity (due to the concerted mechanism), the Diels-Alder reaction is a very powerful reaction and is widely used in synthetic organic chemistry.
A standard echocardiogram or a fetal echocardiogram test usually takes about 30 to 60 minutes. A stress echocardiogram usually takes between 60 and 90 minutes.
10. Most Lexiscan Cardiolite stress tests take approximately three and a half (3 Â½) hours and can be completed in one day. Your test may be scheduled as a two day protocol, which will require you to come in two consecutive days.