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Interfaces areas

The Sa is the bonding interface area. And the calculative value is almost corresponding to the experimential value. This calculative value is described in consideration. [Pg.852]

In many applications there is some sort of airflow interaction between indoors and outdoors through some small openings (small compared with the whole interface area between inside and outside space). [Pg.1049]

The function / incorporates the screening effect of the surfactant, and is the surfactant density. The exponent x can be derived from the observation that the total interface area at late times should be proportional to p. In two dimensions, this implies R t) oc 1/ps and hence x = /n. The scaling form (20) was found to describe consistently data from Langevin simulations of systems with conserved order parameter (with n = 1/3) [217], systems which evolve according to hydrodynamic equations (with n = 1/2) [218], and also data from molecular dynamics of a microscopic off-lattice model (with n= 1/2) [155]. The data collapse has not been quite as good in Langevin simulations which include thermal noise [218]. [Pg.667]

Figure 8 Hypothetical chemical stnicture of the cellu-lose-PMPPlC-PS interface area [41],... Figure 8 Hypothetical chemical stnicture of the cellu-lose-PMPPlC-PS interface area [41],...
For slightly soluble gases, H is defined as a large value (4.2 X 104 bar mol-1 that is the mole fraction of oxygen in H20). The liquid phase controls, kL = Kv For the oxygen transfer rate, the interface area is important. For oxygen bubbles, the surface area of bubbles is defined as ... [Pg.25]

Catalytic Characterization Measurement of the Metal/Gas Interface Area Ac... [Pg.119]

Figure 4.8. (a) Experimental apparatus for measuring the catalyst-electrode metal/gas interface area AG- (b) typical yco2 peak obtained upon reacting the preadsorbed O with C2H4 or CO its area gives N0. (c) Plot of N0 vs the 02 desorption time, tHe, to obtain Nc. [Pg.119]

In principle any standard catalytic metal surface area measuring technique, such as H2 or CO chemisorption can be used to measure the metal/gas interface area Aq or Nq. This is because solid electrolytes such as YSZ chemisorb practically no H2 or CO at any temperature. [Pg.120]

There is currently considerable interest in processing polymeric composite materials filled with nanosized rigid particles. This class of material called "nanocomposites" describes two-phase materials where one of the phases has at least one dimension lower than 100 nm [13]. Because the building blocks of nanocomposites are of nanoscale, they have an enormous interface area. Due to this there are a lot of interfaces between two intermixed phases compared to usual microcomposites. In addition to this, the mean distance between the particles is also smaller due to their small size which favors filler-filler interactions [14]. Nanomaterials not only include metallic, bimetallic and metal oxide but also polymeric nanoparticles as well as advanced materials like carbon nanotubes and dendrimers. However considering environmetal hazards, research has been focused on various means which form the basis of green nanotechnology. [Pg.119]

The microstmcture appeared well mixed although co-continuity of the phases was not obvious. The blends appeared to have a continuous PP phase containing extended, yet isolated, SBR components as shown in Figure 11.17. It appeared to be similar to the microstmcture of the TPV-based on nylon and EPDM. The presence of entrapped air or mumal dissolution was not observed. As the fraction of PP increased, the microstmctures became clustered into larger PP and SBR single phases, with lower SBR-PP interface area. Both the materials were shear thinning. There is a large decrease in the viscosity of the composites at small shear rate. The viscosity values of the phases followed the equation... [Pg.332]

More commonly used is another definition of Gibbs surface excesses, according to which r, is equal to the amount of substance j that must be added to the system (with a constant amount of the substance j = 0) so that the composition of the bulk phases will remain unchanged when the interface area is increased by unity. This definition can also be used when chemical reactions take place in the surface layer. In the case discussed here, the two definitions coincide. The set of surface excesses of all components is sometimes called the surface phase (in contrast to the real surface layer or interphase). [Pg.164]

Biphasic media are macroheterogenous, with a well-defined liquid-liquid interface [25,63] [Fig. 1(g), (h)], or microheterogeneous consisting of an emulsion with a very important interface area [37,38] [Fig. 1-f]. The first medium is used for kinetic studies... [Pg.557]

Example 1. Under the phase separation process, the time dependence of the interface area or the maximum wavevector does not exhibit any specific behavior that could be directly related to the morphological transformations that... [Pg.223]

The use of amphiphilic water-soluble ligands which influence the alkene solubility or increase the catalyst concentration at the interface area of the phases [48,49] ... [Pg.119]

In situations 3 and 4, as much interface area as possible with a minimum volume of bulk liquid is required. However, hydrogenations are not very fast reactions and, in most cases, situations 1 or 2 prevail. [Pg.1533]

The state of mixing generally controls tire mass transfer. In a liquid-liquid system, for example, the reaction rate is based on the mass transfer which depends on the interface area of the two liquid layers. This area is dramatically changed by a change in the mixing rate. If, for example, the agitator is started late, the increase in mass transfer area will lead to a rapid increase in the conversion rate and hence in the heat production rate. [Pg.134]

The capacitance C of the SCR is usually much smaller than that of the double layer in the electrolyte and dominates the AC behavior of the whole system. The capacitance for an electrode of interface area A and an SCR of width W can be calculated according to... [Pg.6]

Fi . 5-37. Degree of transformation of interfadal lattice (1x1) - (5x20) observed as a function of cathodic potential for a gold electrode with a plane (100) in perchloric add solution A(total) = total interface area A(5x20) s interface area of (5x20) supper lattice. [From Kolb-Schneider, 1988.]... [Pg.165]

Here, R is regarded as the sum of the specific energies absorbed in creating new surfaces in fiber r, matrix Rm and at the interface G based on the nominal transverse area neglecting the cylindrical interface area... [Pg.245]

The skin consists of a thin outer layer (epidermis) and a relatively thicker inner layer (dermis). The epidermis is approximately 0.1 mm in thickness, whereas the dermis is generally 2-4 mm thick. Dermoepidermal ridges provide a large interface area between the epidermis and dermis. This is of great importance in that the epidermis, which is not vascularized, receives all its nutrients from the blood supply of the dermis. [Pg.7]


See other pages where Interfaces areas is mentioned: [Pg.471]    [Pg.183]    [Pg.589]    [Pg.327]    [Pg.300]    [Pg.721]    [Pg.26]    [Pg.214]    [Pg.237]    [Pg.695]    [Pg.696]    [Pg.450]    [Pg.203]    [Pg.217]    [Pg.219]    [Pg.1529]    [Pg.169]    [Pg.49]    [Pg.181]    [Pg.137]    [Pg.72]    [Pg.272]    [Pg.90]    [Pg.260]    [Pg.272]    [Pg.210]    [Pg.49]    [Pg.366]   
See also in sourсe #XX -- [ Pg.61 , Pg.107 , Pg.155 , Pg.178 ]

See also in sourсe #XX -- [ Pg.74 ]




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Cross-sectional areas interface

Interface area per unit volume

Interfaces interfacial area

Interfaces reducing area/curvature

Liquid interfaces force-area curves

New Interface Area Function to Investigate Swelling Behavior and Youngs Modulus in Nanocomposites

Proteins interface area

Specific interface area

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