二手核磁共振成像MRI、CT回收

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二手核磁
最后修订:
2012年12月01日 12:50
回收公司 7186

 

   

 

 

   二手核磁共振成像MRI,CT回收,核磁共振维修,CT维修,液氦充装,医院正在使用中的核磁共振成像MRI优先考虑。手机+8613805690379.

      核磁共振成像也称磁共振成像,是利用核磁共振原理,通过外加梯度磁场检测所发射出的电磁波,据此可以绘制成物体内部的结构图像,在物理、化学、医疗、石油化工、考古等方面获得了广泛的应用。

       在磁场的作用下,一些具有磁性的原子能够产生不同的能级,如果外加一个能量(即射频磁场),且这个能量恰能等于相邻2个能级能量差,则原子吸收能量产生跃迁(即产生共振),从低能级跃迁到高能级,能级跃迁能量的数量级为射频磁场的范围。核磁共振可以简单的说为研究物质对射频磁场能量的吸收情况。  

 核磁共振成像(Nuclear Magnetic Resonance Imaging‎,简称NMRI‎),又称自旋成像(spin imaging‎),也称磁共振成像(Magnetic Resonance Imaging‎,简称MRI‎),台湾又称磁振造影,是利用核磁共振(nuclear magnetic resonnance‎,简称NMR‎)原理,依据所释放的能量在物质内部不同结构环境中不同的衰减,通过外加梯度磁场检测所发射出的电磁波,即可得知构成这一物体原子核的位置和种类,据此可以绘制成物体内部的结构图像。

 

  将这种技术用于人体内部结构的成像,就产生出一种革命性的医学诊断工具。快速变化的梯度磁场的应用,大大加快了核磁共振成像的速度,使该技术在临床诊断、科学研究的应用成为现实,极大地推动了医学、神经生理学和认知神经科学的迅速发展。

物理原理

  核磁共振成像是随着计算机技术、电子电路技术、超导体技术的发展而迅速发展起来的一种生物磁学核自旋成像技术。它是利用磁场与射频脉冲使人体组织内进动的氢核(即H+)发生章动产生射频信号,经计算机处理而成像的。原子核在进动中,吸收与原子核进动频率相同的射频脉冲,即外加交变磁场的频率等于拉莫频率,原子核就发生共振吸收,去掉射频脉冲之后,原子核磁矩又把所吸收的能量中的一部分以电磁波的形式发射出来,称为共振发射。共振吸收和共振发射的过程叫做“核磁共振”。核磁共振成像的“核”指的是氢原子核,因为人体的约70%是由水组成的,MRI即依赖水中氢原子。当把物体放置在磁场中,用适当的电磁波照射它,使之共振,然后分析它释放的电磁波,就可以得知构成这一物体的原子核的位置和种类,据此可以绘制成物体内部的精确立体图像。通过一个磁共振成像扫描人类大脑获得的一个连续切片的动画,由头顶开始,一直到基部。

 

  核磁共振成像是随着电脑技术、电子电路技术、超导体技术的发展而迅速发展起来的一种生物磁学核自旋成像技术。医生考虑到患者对“核”的恐惧心理,故常将这门技术称为磁共振成像。它是利用磁场与射频脉冲使人体组织内进动的氢核(即H+)发生章动产生射频信号,经电脑处理而成像的。

 

  原子核在进动中,吸收与原子核进动频率相同的射频脉冲,即外加交变磁场的频率等于拉莫频率,原子核就发生共振吸收,去掉射频脉冲之后,原子核磁矩又把所吸收的能量中的一部分以电磁波的形式发射出来,称为共振发射。共振吸收和共振发射的过程叫做“核磁共振”。

 

 

Used magnetic resonance imaging MRI, CT recycling, MRI repair, CT repair, helium filled, the hospital is being used in magnetic resonance imaging MRI priority. Phone +8613805690379.

      
Magnetic resonance imaging, also known as magnetic resonance imaging, is the use of nuclear magnetic resonance principle, by applying gradient magnetic field detecting the emitted electromagnetic waves, which can be drawn into the internal structure of the object image, in the physical, chemical, medical, petrochemical, archeology, etc. obtain a wide range of applications.

       
Under the effect of the magnetic field, some of the atoms to produce a magnetic different levels, if an energy applied (i.e. the RF field), and this energy can be exactly equal to the energy difference between two adjacent levels, the transition energy generation atomic absorption ( i.e. resonance), the transition from the low level to the high level, the energy level transition of the RF field magnitude range. MRI can simply say for the study of substances on the RF magnetic energy absorption.

Magnetic Resonance Imaging (Nuclear Magnetic Resonance Imaging, referred NMRI), also known as spin imaging (spin imaging), also known as magnetic resonance imaging (Magnetic Resonance Imaging, referred MRI), Taiwan, also known as magnetic resonance imaging, is using NMR (nuclear magnetic resonnance, referred to as NMR) principles, depending on the energy released in the material structures within the different attenuation of different environments, by applying a gradient magnetic field detecting the emitted electromagnetic waves, that constitute the object can be the location and type of nucleus, which can be drawn into the internal structure of the object image.

 
This technique will be used for imaging the internal structure of the human body, they produce a revolutionary medical diagnostic tool. Rapidly changing gradient magnetic field applications, greatly accelerating the speed of magnetic resonance imaging, making the technology in clinical diagnostics, scientific applications become a reality, greatly promoted the medicine, neurophysiology and cognitive neuroscience rapidly.

Physical principles
MRI is with computer technology, electronic circuit technology, superconductor technology and the rapid development of a bio-magnetic nuclear spin imaging technology. It is the use of a magnetic field and radio frequency pulses so that the body tissues precessing hydrogen nuclei (ie, H +) occurs nutation RF signal generated by the computer processing and imaging. Precessing nuclei, the absorption and nuclear precession frequency of the same radio frequency pulses, the frequency of the applied alternating magnetic field is equal to the Larmor frequency of the nuclei resonance absorption occurs, remove the RF pulse, the nuclear magnetic moment of the absorbed energy again form part of the emitted electromagnetic waves, called a resonance emission. Resonance absorption and resonance emission process is called "nuclear magnetic resonance." MRI of the "core" refers to a hydrogen nucleus, because the body is about 70% composed of water, MRI is dependent on water, a hydrogen atom. When the object is placed in a magnetic field, which with the appropriate electromagnetic wave irradiation, so that the resonance, and then analyze it releases the electromagnetic waves can be constituted that the position of the object and types of nuclei, which can be drawn into a precision within the object stereoscopic images. By a magnetic resonance imaging scan of the human brain slices obtained a continuous animation, from the top of the head, has been to the base.

 
MRI, with the computer technology, electronic circuit technology, superconductor technology and the rapid development of a bio-magnetic nuclear spin imaging technology. Doctors take into account patients 'nuclear' fear, so often these doors technique called magnetic resonance imaging. It is the use of a magnetic field and radio frequency pulses so that the body tissues precessing hydrogen nuclei (ie, H +) occurs nutation RF signal generated by the computer processing and imaging.

 
Precessing nuclei, the absorption and nuclear precession frequency of the same radio frequency pulses, the frequency of the applied alternating magnetic field is equal to the Larmor frequency of the nuclei resonance absorption occurs, remove the RF pulse, the nuclear magnetic moment of the absorbed energy again form part of the emitted electromagnetic waves, called a resonance emission. Resonance absorption and resonance emission process is called "nuclear magnetic resonance."

 

 

 

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