Phase contact structures

The wetting ability of an MCFC electrode is closely related to the performance of cell operation especially including electrochemical reaction, and can be expressed as contact angle between electrolyte and electrode. The surface energy of 3 phases, geometric structure of anode electrode and... 

Among other specific applications of PTs as light-emitting materials, it is necessary to mention microcavity LEDs prepared with PTs 422 and 416 [525,526] and nano-LEDs demonstrated for a device with patterned contact structure, and PT 422 blended in a PMMA matrix that emits from phase-separated nanodomains (50-200 nm) [527,528]. 

Peptides larger than 10 to 20 residues adopt conformations in solution through the interplay of hydrogen bonding, electrostatic and hydrophobic interactions, positioning of polar residues on the solvated surface of the polypeptide, and sequestering of hydrophobic residues in the nonpolar interior. Protein shape is dynamic, changing continuously in response to the solvent environment. The retention process in RPLC is initiated as the protein approaches the stationary-phase surface. Structured water associated at the phase surface and adjacent to hydrophobic contact surfaces on the polypeptide is released into the bulk mobile... 

In the first instance (1,3) two types of nickel are used on the side exposed to the gas, large pores are produced in the metal and adjacent to this structure, a network of smaller pores are produced to hold back the electrolyte. The reacting gases diffuse rapidly in the large pores and come in intimate contact with the electrolyte present in the small pores. For the electrochemical reaction po occur, a three phases contact is needed since a gaseous reactant produces a solvated reactior oro uct nd in this process an electron is given or withdrawn from a solid conducting substrate. 

In summary, we have examined the role of structural disjoining pressure in the movement of a three phase contact fine. The movement of the contact fine is an integral process in the displacement of one fluid by another. Practical applications include the spreading of a fluid on a solid surface or the removal of a pollutant drop from a solid surface by the action of a surfactant solution. 

Contact angle hysteresis can be caused by surface roughness, heterogeneity, dissolved substances, and structural changes of the solid at the three-phase contact line. 

From the calculations presented above, it should be clear that coupling effects in multicomponent mass transfer will be influenced not only by the structure of the Fick matrix [/)] but also by the hydrodynamics of two-phase contacting, which influences both the contact time between the phases and the distribution of sizes of droplets or bubbles. Very small bubbles (or drops) may approach the steady-state limit (largest influence of coupling), while larger bubbles will transfer mass in the short-contact regime (least influence of coupling). ... 

The mobile phase—stationary phase contact process is followed by an elution process where an eluent is fed and flows through the length of the stationary phase structure. Different adsorbed species have different affinities to the sorbent, and are therefore eluted at different rates, thereby bringing about their separation. 

Ultimately, we should be concerned with the strategies to optimize electrochemical parameters by materials research. The most momentous strategy is to seek new phases (new structures and compounds) and, indeed, many simple phases have already been explored. Yet, examining any higher compositional complexity increases the possibility that the new phases are chemically unstable when in contact with neighboring phases, and that is why the modification of given phases is of key significance. 

The formation of disperse structures with phase contacts takes place under a great variety of physical-chemical conditions, for instance during sintering and pressing of powders. Disperse systems with phase contacts that form in the course of condensation of a new phase from metastable solutions or melts, are commonly referred to as condensation. If the particles that form... 

Figure 7 shows the joint interfaces in ground C-SiC/Cu-clad-Mo joints made using Ticusil. There is evidence of good braze/composite interaction (Figs. 7a b), and relatively large quantities of Ti (18,6 atom%). Mo (36.4 at%) and Ag (45 at%) are detected within the C-SiC composite (point I, Fig. 7b). The SiC coating on the composite surface has been removed by grinding and an intimate composite-to-braze contact established. Silicon is detected at -15-20 pm distance within the braze region near the interface (point 4, Fig. 7b). As before, the braze matrix displays the Ag-rich and Cu-rich two-phase eutectic structure with the Ag-rich phase preferentially segregating at the C-SiC surface (Fig. 7b). The Ag-rich phase has also preferentially deposited at the interface on the Cu-clad-Mo side (Fig. 7c). Interestingly, there is some carbon dissolution and diffusion in braze (points 1 2, Fig. 7c) and also in Mo (point 5, Fig. 7c) to a depth of -30 pm. Additionally, some Cu (10.6 at%) from the clad layer was detected within the Mo substrate (point 5, Fig. 7c).

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