Easy paths

This paper discusses how tightening environmental regulations in the USA are encouraging a shift from solvent-based to waterborne adhesives for use in flexible packaging applications. It also looks at how new adhesive systems have a relatively easy path to Food Drug Administration clearance for food packaging uses. 

Little is known about valence-shell expansion reactions among still higher row elements, but the considerable oxidative stability of silicones and of tetraalkyl derivatives of group IV elements suggests that valence shell-expansion doesn t provide an easy path for oxygen attack in this group. 

The line-tracing test (LTT) is used to determine the accuracy of a person s fine motor control. A test sheet (s. fig. 10.3) shows a relatively complex road map , 5 mm in width (corresponding to a 2.5 m wide lane). The patient is asked to trace this not-so-easy path with a pencil from start to finish, as quickly as possible, without going over the edges. The number of errors provides a semiquantitative assessment. In addition, the respective number of points can be recorded in the score sheet, (s. tab. 10.10)... 

It will not be good to marry such a female." My friend was shocked and puzzled -- "Does that mean me " I laughed ruefully. The answer was totally typical, totally consistent with my experience, and as far as I was concerned only a fool would ignore it. We managed to stay friends on my terms, and I think she even respected me for it, since it was obviously not an easy path for me to follow. 

If crystal structures are available, their packing can be used to predict reactivity or non-reactivity. Distances of reactive centers are less important, but it is self-evident that close distances and favorable orientation can be advantageous in most cases (see exceptions in Section 2.1.6) and that far distances with obstruction in between will be detrimental. But it is essential that molecules can migrate along easy paths and these must be available for reactivity. 

No Easy Path. Our antitrust laws properly regard conspiracy-fixed prices as a threat to competition, but unrealistically low prices pose a similar threat of reducing the number of competitors. 

There is no easy path out of this maze. Very often a courageous price boost by one producer is timorously not followed by others. 

Photoionizations are likely to be mono-photonic if electron transfer from an excited state is made easy. This may occur if the solvent is a good electron acceptor or if charge-transfer complexation is involved. Each of these provides an easy path to electron transfer. 

Figure 7.9 shows the structure of mica. The van der Waals bonding between the sheets is not usually shown since it is so weak. Mica comes in several forms including muscovite, biotite, and the lesser-known phlogopite variety. Micas are used to provide easy paths for crack propagation in some commercial machinable ceramics. 

A recent introduction to prepreg technology is the use of a resin system such as 3M s Scotchply SP 381, which can be used in a one side tacky (OST) form. Processing using a vacuum bag enables an easy path for air to exit between the plies prior to resin saturation and achieve a composite with less than 0.4% voids using only a vacuum cure. 

Figure 4.1.5. Easy path model for a two-phase ceramic (a) Schematic representation of grains separated by a discontinuous grain boundary phase, (b) Series circuit equivalent according to Bauerle [1969]. (c) Parallel circuit equivalent according to Schouler [1979].

Effects of Grain Shape and the Presence of Distributed Easy Paths. 

Figure 4.1.42. Application of impedance spectroscopy to a study of sodium )3-alumina by T.illey and Strutt [1979] (

Figure 4.143. Circuits proposed for modeling the impedance spectrum of polycrystalline sodium )8-alumina (a) Easy path model according to Lilley and Strutt [1979] (b) Multielement model according to De Jonghe [1979].

The structure should be such that it allows no easy path for rearrangement. 

The history we have given here has, of necessity, left out many important and fascinating details. What we have tried to convey is a sense that nonlinear chemical dynamics has not had an easy path into the hearts and minds of chemists. Skepticism and prejudice delayed for many years the serious study of the phenomena that we shall be discussing. In the end, the combination of persuasive experimental and theoretical work with persistent advocates and visually stimulating phenomena won out. Elements of nonlinear chemical dynamics are now found in mainstream textbooks and introductory courses. Research grants are awarded, international conferences are held, junior faculty are hired. In short, the field is now respectable. This book is an effort to make it not only respectable, but also accessible and comprehensible. 

Molecular mechanism of organic gas-solid reactions The situation at supramolecular gas-solid reactions is different from photoreactions because the gas has to approach the crystal and enter it via easy paths. Thus, even molecular steps when presenting the reactive groups can be the sites of chemical reaction at the expense of nonreactive surface layers with the reactive groups hidden underneath. Several examples have been described. Particularly... 

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