Effect of dielectric properties of solvents on the quality factor for a beyond 900 MHz cryogenic probe model

Designing a solenoid coil of high sensitivity for a cryogenic probe of a novel split magnet

“…The relationship Q S ! x À2 0 gives the corresponding Q S of the AldermanGrant coil at 600 MHz to be about 24,000 (11). This Q S suggests that the two-turn wire coil has reduced sample heating and sample loss as small as that of the Alderman-Grant coil being known for its low E field.…”

“…20,000. Horiuchi et al (11) studied an Alderman-Grant coil by means of simulation and reported that the coil has Q S 10,000 for a sample of low conductivity at 930 MHz. The relationship Q S !…”

“…The sample conductivity r was calculated using r 5 0.2 1 0.106 C, where C is the NaCl concentration in mole (11). Figure 15(a) shows the obtained Q S as a function of r; for distilled water, the TS coil has Q S 5 13,414.…”

Practical aspects of 15N CPMG transverse relaxation experiments for proteins in solution

“…This insensitivity to pulse calibration error was presumably because 1 H was not the observed nucleus. A drawback of using frequent 1 H pulses is sample heating in high-salt solution (25)(26)(27)(28). Overall, the use of H pulses were applied only for the length that corresponded to 12.5 kHz B 1 filed strength.…”

“…Schemes II and III can be useful to reduce the number of 15 N CPMG pulses, and therefore reduce possible probe heating. However, since the employment of frequent 1 H pulses may cause sample heating by dielectric or inductive losses particularly in high salt NMR samples (25)(26)(27)(28), Scheme I may perform better than Scheme II or III for protein samples in aqueous solution at high ionic strength at very high magnetic field strength. In this case, to minimize the total CPMG duration, one may determine the proper CPMG duration based on both signal-to-noise ratio and uncertainty caused by an exponential fitting.…”