Counter migration

It was shown earlier that the NabaiTO-Hemirg model of creep in solids involved the migration of vacancies out of the stressed solid accompanied by counter-migration of atoms to reduce dre length of the solid in the direction of the applied stress. This property could clearly contribute to densification under an external pressure, given sufficient time of application of the stress... 

The tlrermodynamic activity of nickel in the nickel oxide layer varies from unity in contact with tire metal phase, to 10 in contact with the gaseous atmosphere at 950 K. The sulphur partial pressure as S2(g) is of the order of 10 ° in the gas phase, and about 10 in nickel sulphide in contact with nickel. It therefore appears that the process involves tire uphill pumping of sulphur across this potential gradient. This cannot occur by the counter-migration of oxygen and sulphur since the mobile species in tire oxide is the nickel ion, and the diffusion coefficient aird solubility of sulphur in the oxide are both vety low. 

At equilibrium there is zero electric current, and the motor terminal potential difference is the same as that of the cell. The CO3- ion circulation is zero. Inside the cell, ion migration in the potential gradient is matched by counter migration in the concentration gradient. (Hydrogen Fuel)... 

Separation of isotopes is an extremely challenging analytical problem. Lucy and McDonald [4] demonstrated the extraordinary separation power of CE by obtaining a baseline resolution of two chloride isotopes, and Counter migration was... 

Figure 10.5. Separation of chloride isotopes by CE using counter migration (Courtesy of Youchun Shi ).

Depending on the experimental conditions, yUep 3nd //eo may be in the same direction (co-migration), or in opposite directions (counter-migration). The value of the electrophoretic mobUity of an ion is calculated from Eq. 11.6 after separately deteririining fioB and fi o-... 

Format Counter-migration with moderate opposing EOF if possible. Co-migration is faster but gives poorer peak resolution. 

Liu, M. S. Chen, F. T. A. Methods and buffers for detection of nucleic acids hy capillary gel electrophoresis using counter-migrating high-affinity intercalating dyes. U.S. Pat. Appl. Publ. US 2003198964, 2003 Chem. Abstr. 2003, 139, 302967. 

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