General Phenomena

2 DRIVING FORCE OF DIFFUSION-INDUCED INTERFACE MIGRATION (DIIM) 

After the observation of DIGM and LFM in the 1970s, several models and mechanisms were proposed for the driving force of the phenomena. Among them, the coherency strain model of Hillert is now widely supported by some critical experiments of Yoon and others.  

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B. Delmon, and H. Matralis, The remote control mechanism, general phenomena, possible consequences concerning unsteady state processes, unsteady state processes in catalysis, Y.S. Matros, ed. USF, Utrecht, The Netherlands (1991), p. 25. 

Water motion in the ocean is the result of two general phenomena, advection and turbulence. Advection causes water to experience large-scale net displacement (directed transport), whereas turbulent mixing involves the random motion of water molecules... 

I shall now return to comparative retirement, in order to prosecute the train of enquiry and investigation which I have briefly developed in the late lectures the results, I am confident, will be found of importance and will contribute to establish that beautiful and simple theory of chemical synthesis and analysis which I have adopted from a conviction of its application to the general phenomena of chemistry, and which will in due time, I am persuaded, be made the basis of all chemical reasoning respecting the absolute quantities and the proportions of all elementary principles, whether simple or compound. ... 

The types of injury to the liver depend on the type of toxic agent, the severity of intoxication, and the type of exposure, whether acute or chronic. The main types of liver damage are discussed briefly in this section. Whereas some types of damage—for example, cholestasis—are liver specific, others such as necrosis and carcinogenesis are more general phenomena. 

Nearly all metals are thermodynamically unstable in most environments and the result of this instability is corrosion, such as oxidation or some other reaction with the environment. In both "wet" and "dry" corrosion three general phenomena occur. First, material from the metal can dissolve in the environment. This takes forms such as evaporation and volatile compound formation at high temperatures and material dissolution in aqueous solutions. Material loss by such processes may weaken a structure or cause loss of a protective layer. Second, a reaction layer may form on the surface of the metal. Frequently, these layers reduce the rate of a reaction and thus protect the material (passivate a... 

This exponential growth was a general phenomena characterizing science during the 1950s and 1960s (Price 1963),... 

Other important factors include monomer sequence distribution, distribution of graft and crosslink sites along the chains, the occurrence of branching per se, and the general phenomena of side reactions. In addition, stirring rate, the detailed post-reaction "workup procedure, the temperature history, subsequent processing and fabrication conditions, etc. must be considered since these have major effects on the nature of the product. 

Besides nanometer-scale thin film materials of Pt, Pd, and Ru studied above, some preliminary studies on nanometer-scale thin film materials of three other platinum group metals, Rh [20,52], Os [53], and Ir [54], have illustrated the AIREs of all these metals in CO adsorption. Based on studies so far, we can conclude that the AIREs are general phenomena of platinum group metals in chemisorptions of CO and other molecules [20]. 

The effects of three general phenomena over time must be explored ( ) pulses, (2) chemical shifts, and (3) spin-spin coupling. To express the effect of a 90°(tt/2) pulse along the x axis on magnetization that exists initially along the z axis, we use the formalism... 

The potassium enolate of camphor (130) is oxidized with oxaziridine (63a) at — 78 °C to afford a-hydroxyketone (131) in 85% yield (Equation (29)) <84JOC324i>. As mentioned earlier lower yields were observed for the lithium enolate because of the imino-aldol side-reaction. The exclusive formation of the endo product is consistent with attack of the oxaziridine from the sterically least-hindered face of the enolate and is a general phenomena for these reagents. 

Replacement of the normal pyrethroid ester by alternative linkages usually leads to diminution of biological activity. One important exception to this general phenomena is several oxime ether derivatives, in particular, 3-phenoxybenzyl derivatives of various alkyl aryl ketones. Pyrethroid esters derived from certain 2-substituted-[1,1 -biphenyl]-3-methanols have been shown to possess initial and residual activity surpassing that of esters derived from 3-phenoxybenzyl alcohol. Now it has been demonstrated that the same enhancement of activity was observed for alkyl aryl oxime ethers of certain [1,1 -biphenyl]-3-methanols compared to the corresponding 3-phenoxybenzyl alcohol derived oximes. The synthesis, biological activity, including soil activity, structure-activity relationships and toxicity of several of these biphenylmethyl oxime ethers are described. 

Although the general phenomena and the qualitative results described in this section remain valid for any isotherm model, provided they are convex upward and do not intersect, the quantitative results of the shock layer theory presented in Chaptersl4 and 16 are valid only when the adsorption behavior of the mixture components is properly described by the competitive Langmuir isotherm model. The theory shows conclusively that, when the separation factor decreases, the shock layer thickness, hence the width of the mixed zone in the isotachic train, increases in proportion to oc + l)/ a — 1) (Eqs. 16.27a and 16.27b). At the same time, the column length required to reach isotachic conditions increases also indefinitely, as predicted by the ideal model. 

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