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二手核磁共振成像MRI、CT回收

發布者:
二手核磁
最后修訂:
2012年12月01日 12:50
回收公司 11579

 

   

 

 

   二手核磁共振成像MRI,CT回收,核磁共振維修,CT維修,液氦充裝,醫院正在使用中的核磁共振成像MRI優先考慮。手機+8613805690379.

      核磁共振成像也稱磁共振成像,是利用核磁共振原理,通過外加梯度磁場檢測所發射出的電磁波,據此可以繪制成物體內部的結構圖像,在物理、化學、醫療、石油化工、考古等方面獲得了廣泛的應用。

       在磁場的作用下,一些具有磁性的原子能夠產生不同的能級,如果外加一個能量(即射頻磁場),且這個能量恰能等于相鄰2個能級能量差,則原子吸收能量產生躍遷(即產生共振),從低能級躍遷到高能級,能級躍遷能量的數量級為射頻磁場的范圍。核磁共振可以簡單的說為研究物質對射頻磁場能量的吸收情況。  

 核磁共振成像(Nuclear Magnetic Resonance Imaging‎,簡稱NMRI‎),又稱自旋成像(spin imaging‎),也稱磁共振成像(Magnetic Resonance Imaging‎,簡稱MRI‎),臺灣又稱磁振造影,是利用核磁共振(nuclear magnetic resonnance‎,簡稱NMR‎)原理,依據所釋放的能量在物質內部不同結構環境中不同的衰減,通過外加梯度磁場檢測所發射出的電磁波,即可得知構成這一物體原子核的位置和種類,據此可以繪制成物體內部的結構圖像。

 

  將這種技術用于人體內部結構的成像,就產生出一種革命性的醫學診斷工具??焖僮兓奶荻却艌龅膽?,大大加快了核磁共振成像的速度,使該技術在臨床診斷、科學研究的應用成為現實,極大地推動了醫學、神經生理學和認知神經科學的迅速發展。

物理原理

  核磁共振成像是隨著計算機技術、電子電路技術、超導體技術的發展而迅速發展起來的一種生物磁學核自旋成像技術。它是利用磁場與射頻脈沖使人體組織內進動的氫核(即H+)發生章動產生射頻信號,經計算機處理而成像的。原子核在進動中,吸收與原子核進動頻率相同的射頻脈沖,即外加交變磁場的頻率等于拉莫頻率,原子核就發生共振吸收,去掉射頻脈沖之后,原子核磁矩又把所吸收的能量中的一部分以電磁波的形式發射出來,稱為共振發射。共振吸收和共振發射的過程叫做“核磁共振”。核磁共振成像的“核”指的是氫原子核,因為人體的約70%是由水組成的,MRI即依賴水中氫原子。當把物體放置在磁場中,用適當的電磁波照射它,使之共振,然后分析它釋放的電磁波,就可以得知構成這一物體的原子核的位置和種類,據此可以繪制成物體內部的精確立體圖像。通過一個磁共振成像掃描人類大腦獲得的一個連續切片的動畫,由頭頂開始,一直到基部。

 

  核磁共振成像是隨著電腦技術、電子電路技術、超導體技術的發展而迅速發展起來的一種生物磁學核自旋成像技術。醫生考慮到患者對“核”的恐懼心理,故常將這門技術稱為磁共振成像。它是利用磁場與射頻脈沖使人體組織內進動的氫核(即H+)發生章動產生射頻信號,經電腦處理而成像的。

 

  原子核在進動中,吸收與原子核進動頻率相同的射頻脈沖,即外加交變磁場的頻率等于拉莫頻率,原子核就發生共振吸收,去掉射頻脈沖之后,原子核磁矩又把所吸收的能量中的一部分以電磁波的形式發射出來,稱為共振發射。共振吸收和共振發射的過程叫做“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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