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Behavior, systematic observation

With these three different examples it has been demonstrated that the systematics observed for the polymorphism of m-l.c. s is also valid for the side chain polymers, provided that a flexible spacer connects the rigid mesogenic moieties to the polymer main chain. Deviations from this behavior are observed, when the mesogenic moieties are directly linked to the backbone. Under these conditions, normally no liquid crystalline behavior is to be expected, according to the model considerations mentioned in Chap. 2.1. Some examples, however, proved l.c. properties for such systems, which are characterized by two striking properties Very high glass transition temperatures and only smectic structures even in case of short substituents... [Pg.145]

Such principles emerge from practitioners deliberation on personal experiences, complemented occasionally by systematic observation or experimentation. As with the Golden Rule and its equivalents in other cultures ( Do unto others. . . ), it can be surprisingly difficult to recognize shortfalls in one s performance of principles regarding respect, honesty, clarity, and the like, let alone to modify one s behavior to put them into practice. So repetition of such principles in communication guides and careful attention to them by would-be communicators are by no means superfluous. [Pg.231]

Zircon, complete solid-solution behavior is observed, and a plot of the unit cell volume against x shows that Vdgard s Law is followed. When the end members are not is structural, a systematic change in the solubility range in both structures is found as A is varied, and the data have been systematized in terms of a simple, potentially predictive, structure-field map. The pervasive polymorphism of these ABO4 compounds, involving both reconstructive and displacive transformations and metastable structures produced by different sample preparation methods, indicates that the crystal structural stability of substituted compounds needs to be carefully evaluated as a function of temperature to assess the structural integrity of waste-form materials. [Pg.295]

The hydrophobic effect is a term describing the influence of relatively nonpolar (lipophilic) substances on the collective behavior of water molecules in their vicinity. The common expression is that water is more structured or organized when in contact with a lipophilic solute. This behavior was observed in a cellular automata model of a solute in water,42,43 which led to a study in more detail.44 The hydrophobic effect was modeled by systematically increasing the breaking probability, PB(WS), value, encoding an increasing probability of a solute molecule, S, not to associate with water. [Pg.224]

T o stabilize polypropylene against oxidation by atmospheric oxygen, phenolic mononuclear and polynuclear antioxidants containing one hydroxyl group on the aromatic nucleus are used successfully. Thus far the behavior of antioxidants having the structure of polyhydric phenols has not been studied extensively for stabilizing polyolefins. We have systematically observed the properties of dihydric mononuclear phenols with the structure of pyrocatechol and hydroquinone in isotactic poly-... [Pg.184]

The Langmuir isotherm has been readily extended to Hquid-soHd equilibria, first on an empirical basis, then on a more fundamental one. This problem is discussed in the next section (Section 3.2.1.1). The Freimdlich isotherm (Section 3.2.2.4), first used for gas-solid isotherms, has also been extended to liquid-solid equilibria. These isotherms have permitted a correct description of experimental results in a variety of experimental studies involving dilute solutions of a strongly adsorbed component in a pure solvent. The pressure is replaced by the concentration in the equation of the isotherm. As expected from the derivation already discussed, the Langmuir isotherm appears to accoxmt fairly well for adsorption data acquired at low or moderate concentrations. At high concentrations, on the other hand, the activity coefficients of the species in solution are concentration dependent and systematic deviations from Langmuir adsorption behavior are observed. [Pg.78]

The NMR analysis of polymer A tensile bars aged In methanol and Isooctane-methanol solutions showed a systematic decrease In the amount of polyester present with aging time. The same behavior was observed for polymer B except that the loss of polyester was less systematic. Subsequent analysis of the residue confirms that the low molecular weight polyester degradation products are dissolved Into the solution In both cases. [Pg.190]

The first systematic observations of the behavior of proteins with respect to temperature and pressure came from the kinetic work of Suzukiand the thermodynamic work of Hawley. The elliptic phase diagram is shown in Fig. 2. [Pg.380]

Blending of free homopolymer molecules to the polymer tethered silica hybrid systematically alters the viscoelastic response and most clearly observed in the low-frequency response of G and The low frequency plateau value of G decreases with increasing homopolymer content and liquid-like behavior is observed for the blend with 20% silica hybrid material. This is also manifested as a low-frequency Newtonian type behavior for the complex viscosity, p, which becomes independent of frequency for the 20 % silica hybrid blend. On the other hand, the viscosity for the blends with higher hybrid concentration demonstrated a strong power-law behavior at low frequencies, consistent with the solid-like modulus behavior described in Figure 3a. [Pg.262]

Figure 4.18 presents some values of SGs and 5G4 defined in (4.4.53) and (4.4.59) as a function of temperature. Note that values of SG5 are systematically more negative than the corresponding values of 5G4. This is probably a result of the fact that the H(pO interaction becomes larger as the particles come closer together in the final configuration. This is the same behavior we observed for two particles (see Sec. 4.4.6). [Pg.472]

As we have discussed, changes in an environment and behaviors can be assessed directly through systematic observations changes in knowledge, perceptions, police, attitudes, and intentions are only assessable indirectly through survey techniques, usually questionnaires [2]. [Pg.329]

A maintenance program involving both operating and maintenance personnel can help to ensure continued safe operation of an instrumentation and control system. The program should include preventive maintenance supported by systematic monitoring of system behavior. Any observed abnormalities should be reported and investigated as quickly as possible. The maintenance program should provide for ... [Pg.184]


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