Magnetic viscosity magnetization dynamics

I. Symbol for micro-. 2. Symbol for micron. 3. Symbol for dynamic viscosity. 4. Symbol for magnetic or electric dipole moment of a molecule. 5. Symbol for chemical potential. 6. Symbol for permeability fio for permeabihty of vacuum /Xj for relative permeability. 7. Symbol for reduced mass. 

Both chelates have been launched as extracellular contrast agents using doses up to 3 mmol/kg body weight. Both can be formulated as 1.0 molar aqueous solutions with acceptable viscosity (Table 2). These highly concentrated agents are useful in fast dynamic studies such as brain perfusion and fast magnetic resonance angiography (MRA). 

Figure 15. Dynamic hysteresis-loop effects (a) magnetic viscosity and (b) sweep-rate dependence. The sweep-rate dependence amounts to a fluctuation-field [165] or sweep-rate correction to the static coercivity Hco.

An effect closely related to magnetic viscosity is the dependence of the coercivity on the sweep rate rj = dH/dt Hc is largest for high sweep rates, that is, for fast hysteresis-loop measurements (Fig. 15). Sweep-rate and magnetic-viscosity dynamics have the same origin, but there is a very simple way of deriving a relation for the sweep-rate dependence. Let us assume that the energy barriers exhibit a power-law dependence... 

Solvent Mixing. During gradient operation, the HPLC solvents that comprise the mobile phase must be mixed adequately, most commonly with either a static or dynamic mixer. Static mixers rely on laminar-flow dynamics, whereas dynamic mixers use magnetic stirrers. Solvent viscosity affects mixing characteristics inadequate mixing is detected by many UV detectors and may be expressed as an unstable baseline. 

It is traditionally considered that for conventional ionic poly-mers the ions are dispersed throughout the sample in a very low state of aggregation, either as ion pairs or ion quartets. The evidence to support this concept is derived from nuclear magnetic resonance data, viscosity data, and dynamic mechanical measurements. As a recent trend, it is widely accepted... 

Presently, the empirics is ahead of the theory the model mechanisms that we propose we have only been able to quantitate in one instance, that of the dependence of protein reorientational relaxation time on protein concentration. Nonetheless, we have been able to clarify the distinction between macroscopic and microscopic viscosity to measure protein-protein interactions within cells and to demonstrate magnetization transfer from protein protons to solvent protons all of this is consistent with the dynamics of water-protein interactions that we infer and have discussed. 

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