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Mechanically adaptive examples

Another example of PVOH being used in a mechanically adaptive system involves the formation of a PVOH/ferritin microfiber hydrogel via electrospinning. Ferritin is an iron-containing protein with both amine and... [Pg.441]

This issue is key to the whole structure and appearance of the proposed environ-ment. It is central to the choice of object retrieval and interconnection mechanism for example. Since these mechanisms are inextricably linked to the use of adaptive techniques (section 2.2) and formal representations (section 2.3). it can be seen that the choice of Object Oriented approach will effect the entire appearance and concept of the CBASS environment. [Pg.154]

Figure B2.5.2. Schematic relaxation kinetics in a J-jump experiment, c measures the progress of the reaction, for example the concentration of a reaction product as a fiinction of time t (abscissa with a logaritlnnic time scale). The reaction starts at (q. (a) Simple relaxation kinetics with a single relaxation time, (b) Complex reaction mechanism with several relaxation times x.. The different relaxation times x. are given by the turning points of e as a fiinction of ln((). Adapted from [110]. Figure B2.5.2. Schematic relaxation kinetics in a J-jump experiment, c measures the progress of the reaction, for example the concentration of a reaction product as a fiinction of time t (abscissa with a logaritlnnic time scale). The reaction starts at (q. (a) Simple relaxation kinetics with a single relaxation time, (b) Complex reaction mechanism with several relaxation times x.. The different relaxation times x. are given by the turning points of e as a fiinction of ln((). Adapted from [110].
Electron-hopping is the main charge-transport mechanism in ECHB materials. There is precedence in the photoconductivity Held for improved charge transport by incorporating a number of redox sites into the same molecule. A number of attempts to adapt this approach for ECHB materials have been documented. Many use the oxadiazole core as the electron-transport moiety and examples include radialene 40 and dendrimer 41. However, these newer systems do not offer significant improvements in electron injection over the parent PBD. [Pg.338]

Equation (6.20) and the semiquantitative trends it conveys, can be rationalized not only on the basis of lateral coadsorbate interactions (section 4.5.9.2) and rigorous quantum mechanical calculations on clusters89 (which have shown that 80% of the repulsive O2 - O interaction is indeed an electrostatic (Stark) through-the-vacuum interaction) but also by considering the band structure of a transition metal (Fig. 6.14) and the changes induced by varying O (or EF) on the chemisorption of a molecule such as CO which exhibits both electron acceptor and electron donor characteristics. This example has been adapted from some rigorous recent quantum mechanical calculations of Koper and van Santen.98... [Pg.301]

A typical computation such as the ones described here used about 100 adaptively placed mesh points and required about 5 minutes on a Cray 1-S. Of course, larger reaction mechanisms take more time. Also, simpler transport models can be used to reduce computation time. Since the solution methods are iterative, the computer time for a certain simulation can be reduced by starting it from the solution of a related problem. For example, it may be efficient to determine the solution to a problem with a susceptor temperature of 900 K starting from a converged solution for a reactor with a susceptor temperature of 1000 K. In fact, it is typical to compute families of solutions by this type of continuation procedure. [Pg.344]

From the few examples cited, it is clear that a number of mechanisms are used to regulate mRNA stability—just as several mechanisms are used to regulate the synthesis of mRNA. Coordinate regulation of these two processes confers on the cell remarkable adaptability. [Pg.395]

The reaction of X with S must be fast and reversible, close to if not at equilibrium with concentration of S. It can be that there is an intermediate step in which X binds to a protein kinase (a protein which phosphorylates other proteins mostly at histidine residues in bacteria) using phosphate transferred from ATP. It then gives XP which is the transcription factor, where concentration of S still decides the extent of phosphorylation. No change occurs in DNA itself. Here equilibrium is avoided as dephosphorylation involves a phosphatase, though changes must be relatively quick since, for example, cell cycling and division depend on these steps, which must be completed in minutes. We have noted that such mechanical trigger-proteins as transcription factors are usually based on a-helical backbones common to all manner of such adaptive conformational responses (Section 4.11). [Pg.228]


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Mechanically adaptive

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