Ion volume

Properties of Different Solvents. Volumes in Aqueous Solution. The Increment in Volume for a Pair of Ions. Volumes in Different Solvents Compared. Thermal Expansion. 

Principles and Characteristics In metastable atom bombardment (MAB), a metastable atom beam, generated by a gun external to the ion volume, is used to bombard the sample. MAB, based on Penning ionisation, offers unique features for gas-phase ionisation. The energy available for ionisation and fragmentation is discrete (excitation energy of the atom, from 8 to 20 eV),... 

From the measured refractive indices and densities for NaPSS in aqueous NaCl solution the molar refractivities and the apparent molar ion volumes were calculated. The following values were obtained R jaCl = 9.23 cm /mol, R O = 3.73 cnP/mol,... 

A gas chromatograph (GC) can be used for the chromatographic separation of volatile analytes in complex mixtures prior to mass spectrometric analysis. This becomes especially advantageous if the GC elutes directly ( online ) into the ion source of a mass spectrometer, so-called GC-MS coupling. [63-65] Packed GC columns with a high flow can be connected via a jet-separator, but these are almost out of use at present. [66] Capillary columns provide flow rates in the order of a few milliliters per minute, therefore their back end can be connected directly at the entrance of the ion volume. 

Some of the characteristic column volumes outlined in the previous argument were determined by Alhedal et al (11) in the examination of a commercially available reverse phase column packing, Zorbax Cs. These authors examined the exclusion properties of the interstitial volume of the column by measuring the retention volume of a number of salts of different molecular volume.The substances used, in ascending order of ion volume, were as follows,... 

Figure 11-5 Autotitrator delivers titrant from the bottle at the back to the beaker of analyte on the stirring motor at the right. Electrodes in the beaker monitor pH or concentrations of specific ions. Volume and pH readings can go directly to the spreadsheet program in a computer. [Brinkman Instruments, Westbury. NY.]...

Simplified version of the basal medium L-15 that contains only galactose, pyruvate and bulk ions Volume 1(15). 

If methane is introduced into the ion volume through the tube, the primary reaction with the electrons will be a classical El reaction ... 

One of the tenets of normal operation of a mass spectrometer is to introduce as little sanple as possible, while in MS/MS, the sanple sizes are often quite large — up to several mg in trace analyses. Newer instruments are designed for easier source cleaning or utilze ion volumes which are replaceable through the direct probe inlet. 

The physics of electrostatics in aqueous solution has attracted scientists notice for centuries. At present, the solvation of ions, volumes and radii of ions in solution, and ionic interactions are still hotly debated research fields. Recently, thermodynamic, transport and structural data were mutually employed for gaining fruitful physicochemical insights into electrolyte solutions [2]. This chapter recapitulates the essential... 

The problem is to relate v (z) to the surface potential - v (0) or the surface charge density a° = a(O)) and the volume fraction profiles of the components. Early versions t-2) of a polyelectrolyte adsorption model neglected the volume of the small Ions and solved (numerically) the Poisson-Boltzmann equation 13.5.6). A more sophisticated, yet simpler, approach was proposed by Bflhmer et al. who accounted for the Ion volume by adopting a multilayer Stem model, see fig. 5.17. This Is a straightforward extension of the monolayer Stern model discussed in sec. 3.6c. The charges of the ions and the segments are assumed to be located on planes in the centres of the lattice layers. The lattice is thus con-... 

In spite of this, the detailed reason for the expansion on reduction of ceria is often discussed. The problem may be phrased as I) is it because the Cc -ion is bigger than the Ce -ion or 2) is it because the oxide vacancy volume is bigger than the oxide ion volume One reason for the questions is that the effective ion radius is dependent on how many nearest neighbours the ion has (its coordination number). Hong and Virkar analysed this problem, and concluded that the reason is that of point 1). They introduced the concept of an oxide vacancy radius. For ceria the oxide vacancy radius was found to be 0.1164 nm at room temperature which is significantly smaller than the radius of the oxide ion of 0.138 nm. 

---