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Total charge conditions

The electroneutrality condition can be expressed in temis of the integral of the charge density by recognizing the obvious fact that the total charge around an ion is equal in magnitude and opposite in sign to the charge on the central ion. This leads to the zeroth moment condition... [Pg.484]

Solvent Process. In the solvent process, or solvent cook, water formed from the reaction is removed from the reactor as an a2eotropic mixture with an added solvent, typically xylene. Usually between 3 to 10 wt % of the solvent, based on the total charge, is added at the beginning of the esterification step. The mixed vapor passes through a condenser. The condensed water and solvent have low solubiUty in each other and phase separation is allowed to occur in an automatic decanter. The water is removed, usually to a measuring vessel. The amount of water collected can be monitored as one of the indicators of the extent of the reaction. The solvent is continuously returned to the reactor to be recycled. Typical equipment for this process is shown in Figure 2. The reactor temperature is modulated by the amount and type of refluxing solvent. Typical conditions are ... [Pg.39]

From Table 13-31, a total of 394 time increments were necessary to distill all hut 22.08 Ih-mol of the initial charge of 99.74 Ih-mol following the establishment of total-reflux conditions. If this problem had to he solved by an explicit integrator, approximately 25,000 time increments would have been necessary. [Pg.1340]

For constant charging current, and boundary conditions Q = 0 when t = 0, the total charge is... [Pg.99]

Electrical neutrality in the solution requires that the total charge around the ion be balanced by the charge on the ion. This condition is expressed by the... [Pg.338]

Based on electrochemical experiments combined with ex situ analysis by AES, LEED, and RHEED, Wang et al. (2001) suggested the formation of a (2 x 2) (2CO + O) adlayer on Ru(OOOl) at = 0.2 V in CO-samrated HCIO4, similar to the phase formed in UHV after CO adsorption on a (2 x 2)0-covered surface [Schiffer et al., 1997]. Erom the total charge density transferred after a potential step to 1.05 V in a CO-free electrolyte, they concluded that only 60% of the CO content in such an adlayer can be oxidized under these conditions [Wang et al., 2001]. [Pg.485]

The requirements that n and its slope be continuous at z0 allow the expression of A and B in terms of a, b, and z0 a third condition, that the total charge density of the interface be equal to zero, gives... [Pg.61]

The transformed weight corresponding to 5, is the wave function (4.1) normalization condition w = w + W3 = 1. Thus, the solvent force constant matrix elements Km and K m, m = [1,3], bear no dependence on the solute electronic structure, since their components K% and KP°J, are zero [cf. (3.5)]. Then, Si cannot couple to the solute electronic structure, and is unable to monitor any rearrangement — due to the variation of the coefficients Ci and c2 — of the solute total charge distribution p. By contrast, s3 is associated with Kp - = -r) 3,Wi c -c, and is therefore sensitive to the relative change of the weights of the states 1) and 2). [Pg.275]

Scheme 1 Analogy between the observable dehydrocyclization of 1 under low temperature superacid conditions, and the possible cyclization of a 2-octyl cation in catalytic dehydrocyclizations at 400-500 C. In the p-H-bridged cations the positive charge is delocalized, so the position of the (+) simply indicates the total charge in these species. Scheme 1 Analogy between the observable dehydrocyclization of 1 under low temperature superacid conditions, and the possible cyclization of a 2-octyl cation in catalytic dehydrocyclizations at 400-500 C. In the p-H-bridged cations the positive charge is delocalized, so the position of the (+) simply indicates the total charge in these species.
However, a more realistic model for the phase transition between baryonic and quark phase inside the star is the Glendenning construction [16], which determines the range of baryon density where both phases coexist. The essential point of this procedure is that both the hadron and the quark phase are allowed to be separately charged, still preserving the total charge neutrality. This implies that neutron star matter can be treated as a two-component system, and therefore can be parametrized by two chemical potentials like electron and baryon chemical potentials [if. and iin. The pressure is the same in the two phases to ensure mechanical stability, while the chemical potentials of the different species are related to each other satisfying chemical and beta stability. The Gibbs condition for mechanical and chemical equilibrium at zero temperature between both phases reads... [Pg.129]

TOTAL PROTON COUNT FOR THIS STRUCTURE IS (P FOR PROGRAM ESTIMATE) P TOTAL PROTON COUNT BASED UPON NORMAL CONDITIONS IS 8 ARE THERE ANY ABNORMAL VALENCE OR CHARGE CONDITIONS WHICH WOULD AFFECT THIS COUNT (Y/N) N PROTON COUNT FOR NODE 2 (D TO DISPLAY STRUCTURE) ... [Pg.274]

In both ECD and ETD, the initial conditions appropriate to the experiments do not correspond to the ground electronic state of the electron/peptide (ECD) or anion/ peptide (ETD) system. In both cases, there are a myriad of lower-energy electronic states, and this fact presents major challenges to the theoretical study of these processes. In Figure 2, we show qualitative plots of energies as functions of the distance R between a H3C anion donor and a polypeptide having total charge Z. [Pg.165]

The apparent discrepancy could reside in the fact that if potassium ions are available at all, they will form a mica at temperatures near 100°C. Montmorillonite structures below these conditions (pressure and temperature) need not contain potassium at all. However, at the correct physical conditions the 2 1 portion of the montmorillonite must change greatly (increase of total charge on the 2 1 unit) in order to form a mica unit in a mixed layered mineral phase. Since neither Na nor Ca ions will form mica at this temperature, potassium will be selectively taken from solution. Obviously this does not occur below 100°C since cation exchange on montmorillonites shows the reverse effect, i.e., concentration of calcium ions in the interlayer sites. If potassium is not available either In coexisting solids or in solutions, the sodi-calcic montmorillonite will undoubtedly persist well above 100°C. [Pg.88]

Under stationary-state conditions an equal and opposite force is exerted on the volume element by the electric field acting on the ions contained in the volume element. The force on the ions is given by the product of the field strength times the total charge. The latter equals the charge density p times the volume of the element therefore... [Pg.545]

Since in the steady state, it is necessary to maintain a condition of electroneutrality in any macroscopic part of the system, the total charge flux through all cross-sections of the circuit must be the same. In particular, the rate of electron flow in the external circuit is equal to the rate of charge transfer at each electrode/electrolyte interface. [Pg.37]

Grahame derived an equation between a and based on the Gouy-Chapman theory. We can deduce the equation easily from the so-called electroneutrality condition. This condition demands that the total charge, i.e. the surface charge plus the charge of the ions in the whole double layer, must be zero. The total charge in the double layer is /0°° pe dx and we get [59]... [Pg.49]

From Eqs. (3.287) and (3.290), it can be inferred that, when total equilibrium conditions are considered for the precedent and subsequent chemical reactions to the charge transfer reaction, the shape and height of the voltammetric curve are not affected although the half-wave potential shifts toward more cathodic or anodic... [Pg.225]

A sulfonation reaction is performed as a semi-batch reaction in 96% sulfuric acid as a solvent. The total charge is 6000 kg with a final concentration of 3molT1. The reaction temperature is 110°C and Oleum 20% is added in a stoichiometric excess of 30% at constant rate over 4 hours. Under these conditions, the maximum accumulation of 50% is reached after approximately 3 hours addition. [Pg.79]

Putting appropriate conditions on ci and c2 along the outer boundary of Q. and thus on c, the total charge in (7) can be determined a-priori as well. With respect to the reactions, the essential variables therefore are... [Pg.345]


See other pages where Total charge conditions is mentioned: [Pg.487]    [Pg.10]    [Pg.213]    [Pg.1338]    [Pg.1340]    [Pg.53]    [Pg.180]    [Pg.252]    [Pg.228]    [Pg.469]    [Pg.276]    [Pg.113]    [Pg.230]    [Pg.288]    [Pg.326]    [Pg.159]    [Pg.173]    [Pg.16]    [Pg.234]    [Pg.34]    [Pg.388]    [Pg.164]    [Pg.143]    [Pg.515]    [Pg.160]    [Pg.324]    [Pg.78]    [Pg.282]    [Pg.303]    [Pg.11]   
See also in sourсe #XX -- [ Pg.167 ]




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