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Form effects

Table 2 contains the honeycomb sandwich bonding property requirements for the same adhesive. Note that 0.005" thick adhesive has no sandwich bond requirements because it does not contain enough adhesive to form effective fillets and so is not used for sandwich bonding. [Pg.1148]

Mn(III) is able to oxidize many organic substrates via the free radical mechanism [32], The free radical species, generated during oxidation smoothly initiate vinyl polymerization [33-35]. Mn(III) interacts also with polymeric substrates to form effective systems leading to the formation of free radicals. These radicals are able to initiate vinyl polymerization and, consequently, grafting in the presence of vinyl monomers. [Pg.505]

Numerous research activities have focused on the improvement of the protective films and the suppression of solvent cointercalation. Beside ethylene carbonate, significant improvements have been achieved with other film-forming electrolyte components such as C02 [156, 169-177], N20 [170, 177], S02 [155, 169, 177-179], S/ [170, 177, 180, 181], ethyl propyl carbonate [182], ethyl methyl carbonate [183, 184], and other asymmetric alkyl methyl carbonates [185], vinylpropylene carbonate [186], ethylene sulfite [187], S,S-dialkyl dithiocarbonates [188], vinylene carbonate [189], and chloroethylene carbonate [190-194] (which evolves C02 during reduction [195]). In many cases the suppression of solvent co-intercalation is due to the fact that the electrolyte components form effective SEI films already at potential which are positive relative to the potentials of solvent co-intercalation. An excess of DMC or DEC in the electrolyte inhibits PC co-intercalation into graphite, too [183]. [Pg.397]

Aughel and coworkers [63] studied the phase behavior of hydrocarbon-water mixtures in the presence of alkyl(aryl)polyoxyethylene carboxylates for enhanced oil recovery and found good salt tolerance with an alkyl ether carboxy-late (C13-C15) with 7 mol EO and a good microemulsion forming effect with the 3 EO type. [Pg.327]

Since Bis via Gauss s Law of electrodynamics proportional to the local excess free charge it follows that the term fjeV VGj is proportional to the net charge stored in the metal in region G. This net charge, however, was shown above to be zero, due to the electroneutrality of the backspillover-formed effective double layer at the metal/gas interface and thus Dfje w.Gj must also vanish. Consequently Eq. (5.47) takes the same form with Eq. (5.19) where, now, O stands for the average surface work function. The same holds for Eq. (5.18). [Pg.222]

Figure 5.39a shows the residual O Is spectrum obtained in ultra-high-vacuum after repeated cleaning cycle at 350-400°C. It is clear that there is a significant amount of residual O on the Pt surface which cannot be removed with conventional cleaning procedures. This by itself suffices to prove the presence of the omnipresent backspillover-formed effective double layer on the vacuum exposed Pt surface. [Pg.252]

It must be emphasized that the effective double layer is overall neutral, as the backspillover species (O6, Na6+) are accompanied by their compensating (screening) charge in the metal.32,3,35,36 It must also be clarified that this backspillover formed effective double layer is not in general at its pzc (point of zero charge). This happens only at a specific value of the electrode potential, as in aqueous electrochemistry.37... [Pg.339]

The presence of this backspillover formed effective double layer is important not only for interpreting the effect of electrochemical promotion, but also for understanding the similarity of solid state electrochemistry depicted in Fig. 7.3 with the case of emersed electrodes in aqueous electrochemistry (Fig. 7.2) and with the gedanken experiment of Trasatti (Fig. 7.1) where one may consider that H2O spillovers on the metal surface. This conceptual similarity also becomes apparent from the experimental results. [Pg.340]

The parameter a in Equation (11.6) is positive for electrophobic reactions (5r/5O>0, A>1) and negative for electrophilic ones (3r/0Oelectrochemical promotion behaviour is frequently encountered, leading to volcano-type or inverted volcano-type behaviour. However, even then equation (11.6) is satisfied over relatively wide (0.2-0.3 eV) AO regions, so we limit the present analysis to this type of promotional kinetics. It should be remembered thatEq. (11.6), originally found as an experimental observation, can be rationalized by rigorous mathematical models which account explicitly for the electrostatic dipole interactions between the adsorbates and the backspillover-formed effective double layer, as discussed in Chapter 6. [Pg.501]

A number of investigations of the copper-group oxides and dioxygen complexes have been reported. The electronic spectra of CuO, AgO, and AuO were recorded in rare-gas matrices (9), and it was found that the three oxides could be formed effectively by cocondensation of the metal atoms with a dilute, oxygen matrix, followed by near-ultraviolet excitation. The effective wavelengths for CuO or AgO formation were X > 300 nm and for AuO was X > 200 nm. In addition, the laser fluorescence spectrum of CuO in solid Ar has been recorded (97). [Pg.139]

The system under study is assumed to consist of 2A, electrons, possibly in the presence of a nuclear framework. An orbital picture of the quantum behaviour of the system is then introduced on accepting the validity of an independent-particle model where each electron moves in the field of an effective potential v(r), which afterwards is left substantially unspecified. We emphasize, however, that the choice of v(F) is an essential step of any modeling. Besides semiempirical forms, effective potentials v[ (r)] functionally dependent on the electron numeral density n(r) are intuitively bound to play a prominent role in applications. [Pg.205]

Theoretically, a gastight barrier could be placed between the soil and foundation to eliminate radon entry from the soil. Like many other building details, it is much easier to draw such a detail than to actually install it. Many materials form effective retarders to gas transport. The problem is effectively sealing cracks, joints, and penetrations. As anyone who has tried to build an airtight house can tell you, it is not as easy as it seems. [Pg.1273]

On the basis of theoretical calculations Chance et al. [203] have interpreted electrochemical measurements using a scheme similar to that of MacDiarmid et al. [181] and Wnek [169] in which the first oxidation peak seen in cyclic voltammetry (at approx. + 0.2 V vs. SCE) represents the oxidation of the leucoemeraldine (1 A)x form of the polymer to produce an increasing number of quinoid repeat units, with the eventual formation of the (1 A-2S")x/2 polyemeraldine form by the end of the first cyclic voltammetric peak. The second peak (attributed by Kobayashi to degradation of the material) is attributed to the conversion of the (1 A-2S")x/2 form to the pernigraniline form (2A)X and the cathodic peaks to the reverse processes. The first process involves only electron transfer, whereas the second also involves the loss of protons and thus might be expected to show pH dependence (whereas the first should not), and this is apparently the case. Thus the second peak would represent the production of the diprotonated (2S )X form at low pH and the (2A)X form at higher pH with these two forms effectively in equilibrium mediated by the H+ concentration. This model is in conflict with the results of Kobayashi et al. [196] who found pH dependence of the position of the first peak. [Pg.28]

Silver salts are also employed to create more effective chiral catalysts by exchange of counter anions. For example, in the Mizoroki-Heck reaction of alkenyl or aryl halides, silver salts are employed to form effective chiral Pd intermediates by abstracting a halide group from the Pd11 precursor species (Scheme 53).227,228... [Pg.422]

Presumably, the function of M+ is to "cushion the repulsion of the two negative ions. The larger, softer Cs+ can do this more effectively than the smaller, harder ions such as Li+ or Na+. Also, to form these bridged transition states, solvent molecules must be displaced from the solvation sphere of the cations. That process, because of their smaller sizes, would require more energy for the more strongly solvated Li+ and Na+. For the Cs+ ion, which forms effective bridges, the rate of electron exchange has been found to be linearly related to Cs+ concentration. [Pg.726]

S-S contacts. However, conducting pathways are not formed effectively by the stacking of the cation radicals [26]. [Pg.46]

The groups of Marinetti and Genet have shown that several bisphosphetane-derived ligands (58, 59, 61) form effective Ru-based catalysts for the hydrogena-... [Pg.820]

Separation of niobium from tantalum and impurity metals is the most important step in its extraction from the ore. It may be achieved by several methods that include solvent extraction, ion exchange, fractional crystallization, fractional sublimation, and other techniques. Solvent extraction is apphed mostly in several large-scale commercial processes. Although the classical fractional crystalhzation method forms effective separation, it is a tedious... [Pg.629]

Thereafter, some of the difficulties of forming effective teams were considered. First, the complexity of teams was examined in light of two little models the deciding-doing model and a model of the probabihty of team conflict. These led to discussion of the prisoner s dilemma problem recast as the teammate s dilemma problem to help understand why team cooperation is so difficult to achieve. Oftentimes, individuals who cooperate with the team goals are forced to carry freeloaders who choose to do less than their fair share. Understanding this dilemma adds force to the establishment of team ground rules and norms. [Pg.149]


See other pages where Form effects is mentioned: [Pg.268]    [Pg.443]    [Pg.16]    [Pg.307]    [Pg.201]    [Pg.255]    [Pg.395]    [Pg.750]    [Pg.192]    [Pg.270]    [Pg.95]    [Pg.244]    [Pg.650]    [Pg.235]    [Pg.237]    [Pg.102]    [Pg.341]    [Pg.421]    [Pg.14]    [Pg.65]    [Pg.235]    [Pg.187]    [Pg.82]    [Pg.92]    [Pg.120]    [Pg.425]    [Pg.120]    [Pg.16]    [Pg.93]   
See also in sourсe #XX -- [ Pg.93 , Pg.95 ]

See also in sourсe #XX -- [ Pg.461 ]




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