题目内容

Longitudinal relaxation generally occurs:

A. ) faster than transverse relaxation.
B. ) slower than transverse relaxation.
C. ) the same as transverse relaxation.

查看答案

搜索结果不匹配？点我反馈

更多问题

In a 90 – tau – 180 – tau spin echo sequence, the time between the 90 degree excitation pulse and the spin echo maximum is called:

A. ) tau.
B. ) Echo time.
C. ) 180 pulse.

查看答案

A 90 degree pulse aligned along the X-axis is applied creating transverse magnetization. In the rotating frame of reference, if a 180 degree pulse aligned along the X-axis is then applied after a time tau, the vectors will rotate:

A. ) 180 degrees around the X-axis.
B. ) 180 degrees around the Y-axis.
C. ) 180 degrees around the Z-axis.

查看答案

When the spin vectors in the transverse plane have completely randomized due to dephasing:

A. a) the net magnetization is zero within the transverse plane.
B. b) the net magnetization is increased within the transverse plane.
C. c) the net magnetization remains unchanged.

查看答案

Considering the effect of an RF pulse on the net magnetization, the higher the power of the RF field:

A. a) the slower the rotation and smaller the pulse angle.
B. b) the slower the rotation and larger the pulse angle.
C. c) the faster the rotation and larger the pulse angle.

查看答案

Longitudinal relaxation generally occurs:

A. ) faster than transverse relaxation. B. ) slower than transverse relaxation. C. ) the same as transverse relaxation.

In a 90 – tau – 180 – tau spin echo sequence, the time between the 90 degree excitation pulse and the spin echo maximum is called:

A 90 degree pulse aligned along the X-axis is applied creating transverse magnetization. In the rotating frame of reference, if a 180 degree pulse aligned along the X-axis is then applied after a time tau, the vectors will rotate:

When the spin vectors in the transverse plane have completely randomized due to dephasing:

Considering the effect of an RF pulse on the net magnetization, the higher the power of the RF field:

A. ) faster than transverse relaxation.
B. ) slower than transverse relaxation.
C. ) the same as transverse relaxation.