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Relationship with the phenomenon

Various relationships with the phenomenon of Senko-Hanabi... [Pg.73]

The phenomenon of Senko-Hanabi(Japanese sparklers) 68 10.5 Various relationship with the phenomenon of... [Pg.338]

The advantages of SIMS are its high sensitivity (detection limit of ppms for certain elements), its ability to detect hydrogen and the emission of molecular fragments that often bear tractable relationships with the parent structure on the surface. Disadvantages are that secondary ion formation is a poorly understood phenomenon and that quantification is often difficult. A major drawback is the matrix effect secondary ion yields of one element can vary tremendously with chemical environment. This matrix effect and the elemental sensitivity variation of five orders of magmtude across the periodic table make quantitative interpretation of SIMS spectra oftechmcal catalysts extremely difficult. [Pg.151]

Flow movement also has a relationship with the electrokinetic phenomenon, which can promote or retard the motion of the fluid constituents. Electrokinetic effects can be described as when an electrical double layer exists at an interface between a mobile phase and a stationary phase. A relative movement of the two phases can be induced by applying an electric field and, conversely, an induced relative movement of the two will give rise to a measurable potential difference.33... [Pg.700]

As noted previously in Chapter 3, the improved dimensional stability of wood as a result of anhydride modification has been found to be a function of WPG only, irrespective of the anhydride used for modification (Stamm and Tarkow, 1947 Hill and Jones, 1996b Li etal., 2000b). This shows that improved dimensional stability arises due to a bulking phenomenon, caused by the volume occupied by the bonded acyl adducts in the cell wall. The dimensional stabilization of wood modified with crotonic anhydride has also been reported ( etin and Ozmen, 2001). Reductions in the EMC have also been attributed to a bulking phenomenon (Papadopoulos and Hill, 2003), and in at least one example of decay protection (Papadopoulos and Hill, 2002). Further research is needed to determine if this is the case for resistance to other decay organisms. Only with the phenomenon of surface wettability does the relationship between a physical property of chemically modified wood and WPG seem to be broken (Hill and Jones, 1996c) (Table 4.1). [Pg.78]

Some general aspects related to the derivation, and interpretations of ELF analysis, as well as some representative applications have been briefly discussed. The ELF has emerged as a powerful tool to understand in a qualitative way the behaviour of the electrons in a nuclei system. It is possible to explain a great variety of bonding situations ranging from the most standard covalent bond to the metallic bond. The ELF is a well-defined function with a nice pragmatic characteristic. It does not depend neither on the method of calculation nor on the basis set used. Its application to understand new bond phenomenon is already well documented and it can be used safely. Its relationship with the Pauli exclusion principle has been carefully studied, and its consequence to understand the chemical concept of electron pair has also been discussed. A point to be further studied is its application to transition metal atoms with an open d-shell. The role of the nodes of the molecular orbitals and the meaning of ELF values below 0.5 should be clarified. [Pg.82]

In a system that possesses an upper critical solution temperature, df, and are both positive, x decreases as the temperature increases, and, thus, the concentration (f> decreases. That is, the excluded vohune increases as the temperature increases and the volume of the gel also increases. On the other hand, in the system that possesses a lower critical solution temperature, the opposite phenomenon will be observed. Also, if df, and 5 are constant, x should not depend on the polymer concentration. However, the / s determined from the activity measurement of various polymer solutions have been found to exhibit concentration dependence [4, 5]. This fact suggests that the change of free energy due to the contact between solvent and segment contains contributions not only from 2-body interactions but also from more than 3-body interactions. This also has a strong relationship with the mechanism of volmnetric phase transition that will be discussed later. [Pg.72]

In these syntheses the surface area increases with the progress of the reaction via development of pores as the density of the precursor increases without much change in exterior volume. This phenomenon, where the overall size and shape of a material remains constant over the course of a solid state transformation, is called pseudomorphism (<5). Another related phenomena that affects the development of surface area is topotaxy. Here the transformation proceeds in a manner such that the crystallographic planes of the final product bear a relationship with the planes of starting material throughout the bulk (8). [Pg.212]

Imposition of no-slip velocity conditions at solid walls is based on the assumption that the shear stress at these surfaces always remains below a critical value to allow a complete welting of the wall by the fluid. This iraplie.s that the fluid is constantly sticking to the wall and is moving with a velocity exactly equal to the wall velocity. It is well known that in polymer flow processes the shear stress at the domain walls frequently surpasses the critical threshold and fluid slippage at the solid surfaces occurs. Wall-slip phenomenon is described by Navier s slip condition, which is a relationship between the tangential component of the momentum flux at the wall and the local slip velocity (Sillrman and Scriven, 1980). In a two-dimensional domain this relationship is expressed as... [Pg.98]


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