Artifacts, compression

Evans and Baranyai [51, 52] have explored what they describe as a nonlinear generalization of Prigogine s principle of minimum entropy production. In their theory the rate of (first) entropy production is equated to the rate of phase space compression. Since phase space is incompressible under Hamilton s equations of motion, which all real systems obey, the compression of phase space that occurs in nonequilibrium molecular dynamics (NEMD) simulations is purely an artifact of the non-Hamiltonian equations of motion that arise in implementing the Evans-Hoover thermostat [53, 54]. (See Section VIIIC for a critical discussion of the NEMD method.) While the NEMD method is a valid simulation approach in the linear regime, the phase space compression induced by the thermostat awaits physical interpretation even if it does turn out to be related to the rate of first entropy production, then the hurdle posed by Question (3) remains to be surmounted. 

Hot, molten glass is thick and cohesive it can be shaped, and, as it cools down, it hardens while keeping its shape. Solid glass is extremely tough, withstands compression better than steel, is impervious to liquids, and is resistant to chemical attack. All this makes glass useful for making utilitarian artifacts, such as containers for solids and liquids, as well as ornamental and decorative objects (Tite et al. 2002 Tait 1991). 

Fig. 1-18. Transverse section of compression wood tracheids in tamarack (Larix laricina), showing intercellular spaces (IS), middle lamella (M), the outer (S,), and the inner (S2) layer of the secondary wall, and the lumen (L). The So layer contains narrow, branched helical cavities (HC) as well as two wide drying checks (C), an artifact. Transmission electron micrograph. Courtesy of Dr. T. E. Timell.

The observation of the pseudo octahedral and pseudo compressed octahedral stereochemistries for the copper(II) ion then arise as an artifact of fluxional behaviour, Fig. 2 (A) for CuL6 chromophores and Fig. 3 (B) for the latter in CuL4X2 complexes. In... 

In cooperation with a Spanish industrial firm, Vicente Vinas of the Center developed a leaf caster, the Vinyector, which uses a pump and an electromagnetic-compressed air system to direct the flow of water into a chamber where pulp slurry is added. The water is then sucked down into a tank, forming a repair on the artifact as described above. This cycle takes about one minute to complete. 

Pore water assessments evaluate the toxicity of the interstitial water of the sediment to the aquatic organism (Mayer, 1993). The interstitial water is removed from the sediment by sediment compression or centrifugation. The advantage of this assessment is that the equilibrium of the sediment/water interface is more closely evaluated toxicologically, which allows more confidence in the bioavailability assessment. However, toxicity artifacts such as ammonia and sulfide... 

In the intermittent contact mode phase images shown in Fig. 3.74 a clear contrast between the constituent phases can be observed both for the compression-molded hmsPP (panel a), as well as for the blown film (in the machine and transverse direction in panels band c, respectively). The soft EPR phase appears with dark phase contrast indicating that a substantial amount of energy is dissipated in this phase compared to the PP phase. The EPR particles measure 1 pm or smaller in diameter dispersed in the polypropylene matrix. The horizontal lines and the occasional vertical streaks in the images are artifacts of microtoming. 

Load is a product of the environment. It is, in this case, defined as any form of energy within the classical physical spectrum (compressive to electromagnetic waves) capable of making a change in the intrinsic material. The full physical spectrum should be evaluated for interaction with the artifact. In theory, the artifact is stable when it is able to reflect, deflect, absorb, transmit, or otherwise tolerate load without deleterious alteration. 

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