High voltage scan

Accelerating voltage (high voltage) scan. An alternative method of producing a momentum (mass) spectrum in magnetic-deflection instruments. This scan can also be used, in conjunction with a fixed radial electrical field, to produce an ion kinetic energy spectrum. 

Fixed-product ion scans (sector instruments). High-voltage scan or linked scan at constant B /E. Both techniques give a spectrum of all precursor (parent) ions that fragment to yield a preselected product (daughter) ion. 

Capacitive effects cause hysteresis in small amplitude cyclic voltammogram current density-potential plots (16,31-34). Hysteresis in the current density-applied potential plot is brought about by combinations of high voltage scan rate, large... 

The pde to be solved is given by Eq. (12.27), where P is defined by (12.28). is proportional to the potential scan rate v and can be regarded as a dimensionless equivalent to the scan rate. For a given electrode radius a a high P implies a high voltage scan rate. The dimensionless boundary conditions for the LSV experiment... 

Zach J 1989 Design of a high-resolution low-voltage scanning electron microscope Opf/k 83 30-40... 

There are other characteristics of quadrupoles that make them cheaper for attainment of certain objectives. For example, quadrupoles can easily scan a mass spectrum extremely quickly and are useful for following fast reactions. Moreover, the quadrupole does not operate at the high voltages used for magnetic sector instruments, so coupling to atmospheric-pressure inlet systems becomes that much easier because electrical arcing is much less of a problem. 

Transmission electron microscopes (TEM) with their variants (scanning transmission microscopes, analytical microscopes, high-resolution microscopes, high-voltage microscopes) are now crucial tools in the study of materials crystal defects of all kinds, radiation damage, ofif-stoichiometric compounds, features of atomic order, polyphase microstructures, stages in phase transformations, orientation relationships between phases, recrystallisation, local textures, compositions of phases... there is no end to the features that are today studied by TEM. Newbury and Williams (2000) have surveyed the place of the electron microscope as the materials characterisation tool of the millennium . 

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