Weakened

Fig. 11 shows a composite model of the wave at U X =0.25. In the interfering wave on the upper and lower part of the insert metal, (a) is the same phase, and (b) is the opposite phase. A composite wave is attenuated by the weakened interference as the same phase, and is amplified by the strengthened interference as the opposite phase. 

The use of the surface ultrasonic waves seems to be convenient for these purposes. However, this method has not found wide practical application. Peculiarities of excitation, propagation and registration of surface waves created before these time great difficulties for their application in automatic systems of duality testing. It is connected with the fact that the surface waves are weakened by soil on the surface itself In addition, the methods of testing by the surface waves do not yield to automation due to the difficulties of creation of the acoustic contact. In particular, a flow of contact liquid out of the zone of an acoustic line, presence of immersion liquid, availability of chink interval leads to the adsorption and reflection of waves on tlie front meniscus of a contact layer. The liquid for the acoustic contact must be located only in the places of contact, otherwise the influence on the amplitude will be uncontrolled. This phenomenon distorts the results of testing procedure. 

This weakening of Ni-Ni surfaee bonds by adsorbed sulfiir might lead one to expeet that the eorrosion rate should inerease in this ease. In faet, an inereased anodie dissolution rate was observed for Ni Fe (100) in 0.05 M H2SO4 [9], Figure A3.10.4 shows the anodie polarization eiirves for elean and S-eovered single-erystal alloy surfaees. While both surfaees show the expeeted eurrent inerease with potential inerease, the sulfur-eovered surfaee elearly has an inereased rate of dissolution. In addition, the sulfiir eoverage (measured using... 

The Fe-N mode is at 222 in the R state and 207 cnY in the T state for the a subunits, but only shifted to 218 T state for the (3 subunits. This is consistent with the interpretation that the Fe-imidazole interations are weakened more in the T state of the a subunits than p subunits. Time-resolved resonance Raman studies have shown that the R T switch is complete on a 10 ps tuuescale [38]. Finally, UV excitation of the aromatic protein side chains yields... 

Figure Bl.3.7. A WMEL diagram for the seventh order Raman echo. The first two field actions create the usual Raman vibrational coherence which dephases and, to the extent that inliomogeneity is present, also weakens as the coherence from different cliromophores walks oflP. Then such dephasing is stopped when a second pair of field actions converts this coherence into a population of the excited vibrational state / This is followed by yet another pair of field actions which reconvert the population into a vibrational coherence, but now one with phase opposite to the first. Now, with time, the walked-oflP component of the original coherence can reassemble into a polarization peak that produces the Raman echo at frequency oi = 2(o - (O2...

In certain alloys and under certain environmental conditions, selective removal of one metal (the most electrochemically active) can occur that results in a weakening of the strength of the component. The most common example is dezincification of brass [164, 165]. The residual copper lacks mechanical strength. 

The electrode potential of aluminium would lead us to expect attack by water. The inertness to water is due to the formation of an unreactive layer of oxide on the metal surface. In the presence of mercury, aluminium readily forms an amalgam (destroying the original surface) which is. therefore, rapidly attacked by water. Since mercury can be readily displaced from its soluble salts by aluminium, contact with such salts must be avoided if rapid corrosion and weakening of aluminium structures is to be prevented. 

The effect of the Axilrod-Teller term (also known as the triple-dipole correction) is to make the interaction energy more negative when three molecules are linear but to weaken it when the molecules form an equilateral triangle. This is because the linear arrangement enhances the correlations of the motions of the electrons, whereas the equilateral arrangement reduces it. 

It can be readily confirmed thaf by decreases as the number of bonds N increases and/or llieir length (r ) decreases. This relationship between the bond strength and the number of neighbours provides a useful way to rationalise the structure of solids. Thus the high coordination of metals suggests that it is more effective for them to form more bonds, even though each individual bond is weakened as a consequence. Materials such as silicon achieve the balance for an infermediate number of neighbours and molecular solids have the smallest atomic coordination numbers. 

The rearranging entity has been shown to be the bivalent cation the adjacent charges may so weaken the N—N link that charges of nearly integral size may be built up in the 4 and 4 positions. In the bent, but strainless, cation the minimum separation of the two p-positions would suffice for the establishment of a lai ely electrostatic bond, which could pass smoothly into the covalent rearrangement product (benzidine). 

Analogously, water is extremely efficient in weakening hard Lewis add - hard Lewis base interactions. Consequently, when aiming at catalysis by hard Lewis adds, the inefficiency of the interaction between the catalyst and the substrate is a serious problem. Strangely enough, this characteristic of water is not recognised by many researchers working with hard Lewis acids in... 

In any case, I eventually recovered (and so did Jerry), but my immune system must have suffered serious damage, which manifested itself three years later, when I collapsed in my office one day and was found to be bleeding internally from a form of rare stomach cancer, which necessitated major surgery but was fortunately localized. I again recovered and have had no further difficulties since. Whether weakening and knocking out my immune system to overcome the previous problems had any effect is not clear, but it could have been a factor. Despite my health problems I was able to continue my work without much interruption, and the scientific productivity of my group has not... 

S—Cg is perpendicular to the amide plane of the / -lactam and therefore weakened. The S—bond, on the other hand, is not affected by electronic interactions with the benzamide plane. It was now thought, that a bridging of the thiazolidine moiety would bring the —S bond into a more orthogonal position with respect to the amide plane of the new lactam and make this bond more fragile. The tricyclic thiazolidine was synthesized as described above and fulfilled the predictions (J.E. Baldwin, 1978). 

We attributed the decreased bond dissociation energy in propene to stabilization of allyl radical by electron delocalization Similarly electron delocalization stabilizes benzyl rad ical and weakens the benzylic C—H bond... 

With electrons flowing from ethylene to zirconium the Zr—CH3 bond weakens the carbons of ethylene become positively polarized and the methyl group migrates from zirconium to one of the carbons of ethylene Cleavage of the Zr—CH3 bond is accom panied by formation of a ct bond between zirconium and one of the carbons of ethylene m Step 3 The product of this step is a chain extended form of the active catalyst ready to accept another ethylene ligand and repeat the chain extending steps... 

At one time thiols were named mercaptans Thus CH3CH2SH was called ethyl mercaptan according to this system This nomenclature was abandoned beginning with the 1965 revision of the lUPAC rules but is still sometimes encountered When one encounters a thiol for the first time especially a low molecular weight thiol its most obvious property is its foul odor Ethanethiol is added to natural gas so that leaks can be detected without special equipment—your nose is so sensitive that it can detect less than one part of ethanethiol m 10 000 000 000 parts of arr The odor of thiols weakens... 

Acetate and triacetate exhibit moderate changes in mechanical properties as a function of temperature. As the temperature is raised, the tensile modulus of acetate and triacetate fibers is reduced, and the fibers extend more readily under stress (see Fig. 4). Acetate and triacetate are weakened by prolonged exposure to elevated temperatures in ah (see Fig. 5). 

Other Properties. Polyester fibers have good resistance to uv radiation although prolonged exposure weakens the fibers (47,51). PET is not affected by iasects or microorganisms and can be designed to kill bacteria by the iacorporation of antimicrobial agents (19). The oleophilic surface of PET fibers attracts and holds oils. Other PET fiber properties can be found ia the Hterature (47,49). 

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