Reduction entropy

Usually, dissolution of a small amount of one compound in a pure liquid is enthalpically unfavourable and driven by an increase in (mixing) entropy. At room temperature, the opposite is true for the dissolution of a small apolar compound in water. This unexpected behaviour is referred to as the hydrophobic effect [4]. Classically, this effect has been rationalised by ordered water structures around apolar compounds (entropy reduction) and the increase in number... 

The second stage is the hydration of the gaseous ions, and is exothermic because of the attractive forces operating between the ions and the polar water molecules. There is an accompanying reduction in entropy, as the gas phase ions have their motions constrained to a particular volume (1 dm3) and the ions, as they are hydrated, cause the restriction of motion of a number of water molecules, leading to a further entropy reduction. 

FIGURE 6-7 Rate enhancement by entropy reduction. Shown here... 

More weight should be given to Gee s remark (62) — made already in 1946and repeated in 1966 — that many theoretical treatments of network behaviour ignore the problem of molecular packing. Any strain-dependence of the entropy reduction due to the packing, will lead to a correction in the stress.- This matter will be the main subject of the next section. 

Dimino and Parladori, 1995] Dimino, G. and Parladori, G. (1995). Entropy reduction in high quality audio coding. In Proc. of the 99th. AES-Convention. Preprint 4064. 

First of all, we will touch a widely believed misunderstanding about impossibility of using the second law of thermodynamics in the analysis of open systems. Surely, the conclusion on inevitable degradation of isolated systems that follows from the second law of thermodynamics cannot be applied to open systems. And particularly unreasonable is the supposition about thermal death of the Universe that is based on the opinion of its isolation. The entropy production caused by irreversible energy dissipation is, however, positive in any system. Here we have a complete analogy with the first law of thermodynamics. Energy is fully conserved only in the isolated systems. For the open systems the balance equalities include exchange components which can lead to the entropy reduction of these systems at its increase due to internal processes as well. 

Garrard, S.M., Longenecker, K. L., Lewis, M. E., Sheffield, P.J., Derewenda, Z. S., Expression, purification, and crystallization of the RGS-like domain from the Rho nucleotide exchange factor, PDZ-RhoGEE, using the surface entropy reduction approach. Protein Expr. Purif. 2001, 21, 412-416. 

The unattainabiiity formulation of the Third Law of Thermodynamics is briefly reviewed in Sect. 2.1. It puts limitations of the quest for absolute zero, and in its strongest mode forbids the attainment of absolute zero by any method whatsoever. But typically it is stated principally with respect to thermal-entropy-reduction refrigeration (TSRR). TSRR entails reduction of a refrigerated system s thermal entropy, i.e., its localization in the momentum part of phase space (in momentum space for short). The possibility or impossibility of overcoming these limitations via TSRR is considered, in Sects. 2.2. and 2.3. with respect to standard TSRR, and in Sect. 2.4. with respect to absorption TSRR. (In standard TSRR, refrigeration is achieved at the expense of work input in absorption TSRR, at the expense of high-temperature heat input.)... 

The quest for absolute zero via configurational-entropy-reduction refrigeration (CSRR)... 

A reduction of the configurational entropy of the chains in the interaction zone this entropy reduction results from the decrease in the volume available for the chains when these are either overlapped or compressed. This is referred to as volume restriction interaction, entropic or elastic interaction, and is described by a free energy of interaction, G j. 

The first term is the contribution of translation, the second term results from entropy reduction due to the orientational order of rigid rods, and the third term is the second virial term. The higher virial terms are neglected. 

In summary, electrostatic repulsion stabilizes lamellar phases in ionic systems, whereas entropy reduction stabilizes lamellar phases in nonionic systems or in ionic systems in apolar solvents or in high ionic strength water. Also, the presence of suitable cosurfactants (generally alcohols), which increase the flexibility of the membranes, leads to the formation of dilute lamellar phases, for example, in the system brine-SDS-pentanol [133] or brine-SDS-pentanol-dodecane [134]. Recently, it was shown [135] that two distinct lamellar phases coexisted in the dilute region of the system cetylpyridinium chloride-hexanol-brine. The two phases differ in turbidity, viscosity, density, and some other physical properties. One of these lamellar phases is classically stabilized by the competition between van der Waals, hydration, and electrostatic forces. The other phase is entropically stabilized. The difference between electrostatically and sterically stabilized lamellar phases was demonstrated by transmission electron microscopy on thin vitrified... 

Figure 1.13. Illustration of entropy reduction on application of force F to network chain (a) chain at equilibrium (b) chain as force is being applied (c) final state with force applied.

The implication of the word total is that it is possible for entropy of a system to decrease when heat is transferred out however, the increase in entropy outside the system will be greater than the entropy reduction within the system. Physically, entropy is a measure of the amount of energy that is not available to produce work. Work and mechanical energy are fully useable and therefore have no associated entropy and any process that generates entropy is irreversible. 

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