odometer
发表于 2025-3-21 18:14:30
书目名称MRI Physics for Radiologists影响因子(影响力)<br> http://figure.impactfactor.cn/if/?ISSN=BK0620242<br><br> <br><br>书目名称MRI Physics for Radiologists影响因子(影响力)学科排名<br> http://figure.impactfactor.cn/ifr/?ISSN=BK0620242<br><br> <br><br>书目名称MRI Physics for Radiologists网络公开度<br> http://figure.impactfactor.cn/at/?ISSN=BK0620242<br><br> <br><br>书目名称MRI Physics for Radiologists网络公开度学科排名<br> http://figure.impactfactor.cn/atr/?ISSN=BK0620242<br><br> <br><br>书目名称MRI Physics for Radiologists被引频次<br> http://figure.impactfactor.cn/tc/?ISSN=BK0620242<br><br> <br><br>书目名称MRI Physics for Radiologists被引频次学科排名<br> http://figure.impactfactor.cn/tcr/?ISSN=BK0620242<br><br> <br><br>书目名称MRI Physics for Radiologists年度引用<br> http://figure.impactfactor.cn/ii/?ISSN=BK0620242<br><br> <br><br>书目名称MRI Physics for Radiologists年度引用学科排名<br> http://figure.impactfactor.cn/iir/?ISSN=BK0620242<br><br> <br><br>书目名称MRI Physics for Radiologists读者反馈<br> http://figure.impactfactor.cn/5y/?ISSN=BK0620242<br><br> <br><br>书目名称MRI Physics for Radiologists读者反馈学科排名<br> http://figure.impactfactor.cn/5yr/?ISSN=BK0620242<br><br> <br><br>
Indolent
发表于 2025-3-21 23:12:17
Radiofrequency Pulseurrent through a wire, we create an electromagnetic field. That is, we have both an electrical field and a magnetic field at the same time, which means that either a charged particle or a “magnetizable” substance would experience a force when placed in this region. Now if we make that current an . c
跟随
发表于 2025-3-22 01:26:26
http://reply.papertrans.cn/63/6203/620242/620242_3.png
Anticlimax
发表于 2025-3-22 08:11:21
Gradientshow these different intensities are arranged in space to produce an image. There are a number of ways of doing this, but in this section, we will be concerned only with the most widely used method: two dimensional Fourier transform (“2DFT”) reconstruction.
rheumatism
发表于 2025-3-22 08:55:53
The Slice Select Gradientdient imposes a gradual change in the main magnetic field from the head to the foot end of the patient. If we graph the z gradient with the magnitude of the magnetic field on the y axis and the position along the long axis of the body on the x axis, then we obtain the straight line shown in the grap
PRO
发表于 2025-3-22 15:17:55
The Phase Encoding Gradiention just as we did for the x axis. However, if we did that, then we would not be able to uniquely specify whether a given frequency belonged to the x or the y axis, and the computer would get confused and render us an improper image reconstruction. So we must do something else, and in fact, all comm
MERIT
发表于 2025-3-22 19:00:08
http://reply.papertrans.cn/63/6203/620242/620242_7.png
happiness
发表于 2025-3-23 00:49:16
Wrapping up Basic Conceptsrequency change; and the y gradient produces a phase change. It is important to realize that each gradient is the same physical phenomenon: a change in the magnetic field from one point in space to another. Also, each gradient produces the same basic effect on protons: the vector precession frequenc
avenge
发表于 2025-3-23 02:57:35
http://reply.papertrans.cn/63/6203/620242/620242_9.png
persistence
发表于 2025-3-23 09:06:24
Motion devices used to control motion artifacts and MR angiography. Although we will try to explain every phenomenon in terms of the principles that we have already learned, this may not always be possible because of the complexity of this subject. However, we will be able to explain most things; and we w