Search results
Results From The WOW.Com Content Network
A Hahn-echo decay experiment can be used to measure the spin–spin relaxation time, as shown in the animation below. The size of the echo is recorded for different spacings of the two pulses. This reveals the decoherence which is not refocused by the π pulse. In simple cases, an exponential decay is measured which is described by the T 2 time.
Gradient RGB/CMY color wheel Seven-color and twelve-color color circles from 1708 (attributed to Claude Boutet) Wilhelm von Bezold's 1874 Farbentafel. A color wheel or color circle [1] is an abstract illustrative organization of color hues around a circle, which shows the relationships between primary colors, secondary colors, tertiary colors etc.
Unlike spin echo, gradient echo does not need to wait for transverse magnetisation to decay completely before initiating another sequence, thus it requires very short repetition times (TR), and therefore to acquire images in a short time. After echo is formed, some transverse magnetisations remains.
; Created in LibreOffice 4 with this LibreLogo program. ; Usage: Put this code into an English language document in LibO Writer, ; and click on the Start icon of the View»Toolbars»Logo toolbar.
The only difference between the MRI k-space and the NMR time domain is that a gradient G is present in MRI data acquisition, but is absent in NMR data acquisition. As a result of this difference, the NMR FID signal and the MRI spin-echo signal take different mathematical forms:
Domain coloring plot of the function f(x) = (x 2 − 1)(x − 2 − i) 2 / x 2 + 2 + 2i , using the structured color function described below. In complex analysis, domain coloring or a color wheel graph is a technique for visualizing complex functions by assigning a color to each point of the complex plane. By assigning points on the ...
Stake. Gradient maps are both at the center and at the basic level of map making on Wikipedia. A simple blank map and fill with color tool are needed. To continue to build a coherent Wikipedia display, this page suggests the most suitable SVG source files together with a blue-based color ramps from academic, screen friendly, print friendly, and color-blind friendly ColorBrewer2 by cartography ...
The effect of a uniform magnetic field gradient in the z-direction on spin I, is considered to be a rotation around z-axis by an angle = γ I Gz; where Gz is the gradient magnitude (along the z-direction) and γ I is the gyromagnetic ratio of spin I. It introduces a phase factor to the magnetizations: Φ (z,τ) = (γ I)(Gz)(τ)