sslin
第2楼2006/07/31
简介: Pdf 文档五页, 属于固体核磁相关的名词解释, 也包括了许多液体核磁的用语. 摘录十个范例如下:
1. B0: The static magnetic field. The magnetic flux density is expressed in tesla, T, or often, as an equivalent 1H resonance frequency (for example, 300 MHz for a 7 T magnet).
2. Deconvolution: Mathematical process used to determine the intensities of overlapping lines.
3. digital resolution: This depends on the Fourier number. The bigger the Fourier number the greater the number of data points per Hz of the spectrum and the higher the digital resolution.
4. Gain: Amplification applied to the received signal.
5. Gauss: Non-SI unit of magnetic field flux density. The SI equivalent is Tesla (T), 1 T = 10,000 G
6. lineshape The shape of individual lines in a spectrum. Commonly, Gaussian or Lorentzian or a mixture of the two, are encountered experimentally.
7. zero filling: If the number of data points is not a power of two then zeroes are added to the acquired data so that the total number of points Fourier transformed is 2n. Zero filling adds no signal to the spectrum but it can improve resolution
8. resolution enhancement: The opposite of linebroadening. An FID multiplied by an appropriate combination of increasing and decaying functions can yield extra resolution in a spectrum. See “Processing”
9. Saturation: Condition that arises when there is no population difference between excited and ground states. No signal is observable under such conditions.
10. T2* A time-constant sometimes used to describe the decay of the observed time-domain signal (T2* d T2). The shorter T2* the broader the associated signal(s) in the spectrum.