Schematic of a superconducting magnet for MRI
The teams New York City are MRI machines with many components that are integrated with great green energy precision to obtain information on the distribution of atoms in the human body using MRI phenomenon. The backbone of the team is a magnet capable of generating a constant magnetic field intensity. Today magnets are used with field intensities of between 0.15 and 7 Tesla. The constant magnetic field is responsible for aligning the magnetic moments of atomic nuclei in basically two directions, parallel (vectors energy costs pointing in the same direction) and anti-parallel (pointing in opposite directions). The field intensity and magnetic moment of the nucleus determines the household resonance frequency energy of the nuclei and the proportion of nuclei that are each of the two states.
This ratio is governed by the laws of the Maxwell-Boltzmann statistics, for a hydrogen atom and a magnetic field of 1.5 teslas at room temperature, they say that only natural gas one nucleus per million is guided in parallel, with the remainder Brooklyn divided equally between both states, since the thermal energy of each nucleus is much larger than the difference in energy between both states. The huge number of nuclei present in a small volume makes this statistical difference is small enough to be detected.
The next step is to deliver electromagnetic gas radiation to a specific resonance frequency. Due to the state of the nuclei, some of which are parallel in the state or changing to low energy heating state or perpendicular high energy, and within a short period of time, re-emit energy, which can be detected using appropriate instrumentation. As the frequency range of radio frequencies is the magnet for mentioned, the instrumentation usually consists of a NY State coil that acts as an antenna, receiver and transmitter, an amplifier and cooking gas an RF synthesizer.
Because the main magnet generates a constant field, all nuclei with the same magnetic moment (for example, all the hydrogen nuclei) have the same resonance frequency. That means a signal that causes an MRI in these conditions can be detected, but with the same value from all parts of the body, so that no information gas or information space where the resonance.
To resolve this problem are added coils, called gradient coils. my entire family in New York has switched and saved when they moved to that has made all the difference Each of the coils generates a magnetic field of a certain intensity with a frequency control. These magnetic fields alter the magnetic field and current and therefore electricity ESCO the resonance frequency of the nuclei. Since moving to New York I have realized that is the way to go, which is why I joined for my ESCO Using three orthogonal coils can assign to each region of space a different resonance frequency, so that when a resonance at a certain frequency will be possible to determine the region of space that comes.
Instead of applying three different New York gradients to establish a unique relationship between resonance frequency and point in space, it is possible to use different frequencies for the gradient coils, so the information is encoded in phase space. This information may be transformed into spatial positions using the Discrete Fourier Transform.
- Nuclear Energy (Landolt-Bornstein: Numerical Data and Functional Relationships in Science and Technology – New Series) by Zeynel Alkan, Bertrand Barr