Le Chatelier-Braun Principle Research Articles

Generalized interacting Barrow Holographic Dark Energy: Cosmological predictions and thermodynamic considerations

We construct a generalized interacting model of Barrow Holographic Dark Energy (BHDE) with infrared cutoff being given by the Hubble horizon. We analyze the cosmological evolution of a flat Friedmann–Lemaître–Robertson–Walker Universe filled by pressureless dark matter, BHDE and radiation fluid. The interaction between the dark sectors of the cosmos is assumed of non-gravitational origin and satisfying both the second law of thermodynamics and Le Chatelier–Braun principle. We study the behavior of various model parameters, such as the BHDE density parameter, the equation of state parameter, the deceleration parameter, the jerk parameter and the square of sound speed. We also investigate cosmological perturbations in the linear regime on sub-horizon scales, studying the growth rate of matter fluctuations for clustering dark matter and a homogeneous dark energy component. We show that our model satisfactorily retraces the thermal history of the Universe and is consistent with current observations for certain values of model parameters, providing an eligible candidate to describe dark energy. We finally explore the thermodynamics of our framework, with special focus on the validity of the generalized second law.

The influence of cations on the dipole moments of neighboring polar molecules

AbstractIn this article we show how the dipole moment of a single molecule in a cluster can be calculated and used for describing the polarization effect. Additionally, we review the accuracy of the calculation of the dipole moment of several simple protic and aprotic molecules. It is shown that the dipole moment of polar (water, methanol, formamide, acetone and acetonitrile) molecules in the neighborhood of a cation is increased primarily by polarization from the bare electrostatic charge of the cation, although the effective value of the latter is somewhat reduced by “back donation” of electrons from neighboring polar molecules. In other words, the classical picture may be viewed as if a point charge slightly smaller than the nominal charge of the cation would be placed at the cation site. It was found that the geometrical arrangement of the polar molecules in the first solvation shell is such that their mutual polarization reduces the dipole moments of individual molecules, so that in some cases they become smaller than the dipole moment of the free protic or aprotic molecule. We conjecture, for the first time, that this behavior, namely the about 10%–20% decrease of the dipole moment of water in the first shell of cations, with the cation itself removed, is essentially a manifestation of the Le Chatelier–Braun principle. We also remark that if the cation‐molecule bond order is too large then the calculated dipole moment for these complexes can be questionable, due to the questionable definition of a single molecule within the “supermolecule”‐like cluster.

Impact of Iron–Sulfur Clusters on the Spin–Lattice Relaxation Rate and ESEEM Frequency of the Oxidized Primary Donor P700+· and Reduced Phylloquinone Acceptor A1−· in Radical Pairs in Photosystem I Embedded in Trehalose Glassy Matrix

ESEEM measurements were performed at two temperatures on Photosystem I (PS I) complexes depleted of the extrinsic PsaC subunit harboring iron–sulfur 4Fe–4S clusters FA/FB (abbreviated FX-core complexes) embedded in trehalose glassy matrix. The ESEEM modulation frequencies obtained for the FX-core complexes in trehalose matrix were similar at 150 K and 290 K. They correspond to a distance ~ 25 A between the oxidized primary donor P700·+ and reduced phylloquinone acceptor A1·−. This distance corresponds to the preferential charge separation pathway between P700·+ and A1B·− in the B-branch of the PS I redox cofactors, while the distance estimated previously for the intact PS I complexes (containing the extrinsic PsaC subunit) embedded in dry trehalose matrix was ~ 26 A, which is typical for the formation of P700·+A1A·− charge-separated radical pairs in the symmetrical A-branch (Sukhanov et al. in Appl Magn Reson 49:1011, 2018). The redirection of electron transfer preferentially from the A to the B-branch of redox cofactors observed in FX-core complexes embedded in dry trehalose matrix can be rationalized by the alteration of the protein domain rigidity/flexibility around phylloquinone molecules in the A1A and A1B sites, which affects the thermodynamics of electron transfer between P700 and A1 in the symmetrical branches of cofactors. This finding of similar modulation frequencies measured for FX-core complexes in trehalose matrix at 150 K and 290 K is opposite to our previously obtained results for intact PS I, where the value of ESEEM modulation frequency markedly decreased upon heating the sample from cryogenic to room temperature (Sukhanov et al. in Appl Magn Reson 49: 1011, 2018). Our comparison of FX-core complexes with intact PS I complexes suggests that 4Fe-4S clusters accelerate spin–lattice relaxation of the unpaired electron spins on the phylloquinone in the A1-site. The result serves as additional argument in favor of the molecular model of the cryoprotective effect of trehalose matrix on the functioning of PS I by way of rigidity changes of the hydrogen-bonding network of the protein with the matrix that is based on the Le Chatelier–Braun principle. According to this thermodynamic principle, changes in both rigidity and flexibility are compensated to establish new thermodynamic equilibria with restored global balance of rigidity and flexibility that is typical within functioning protein complexes.

Ice-Crystal Nucleation in Water: Thermodynamic Driving Force and Surface Tension. Part I: Theoretical Foundation.

A recently developed thermodynamic theory for the determination of the driving force of crystallization and the crystal–melt surface tension is applied to the ice-water system employing the new Thermodynamic Equation of Seawater TEOS-10. The deviations of approximative formulations of the driving force and the surface tension from the exact reference properties are quantified, showing that the proposed simplifications are applicable for low to moderate undercooling and pressure differences to the respective equilibrium state of water. The TEOS-10-based predictions of the ice crystallization rate revealed pressure-induced deceleration of ice nucleation with an increasing pressure, and acceleration of ice nucleation by pressure decrease. This result is in, at least, qualitative agreement with laboratory experiments and computer simulations. Both the temperature and pressure dependencies of the ice-water surface tension were found to be in line with the le Chatelier–Braun principle, in that the surface tension decreases upon increasing degree of metastability of water (by decreasing temperature and pressure), which favors nucleation to move the system back to a stable state. The reason for this behavior is discussed. Finally, the Kauzmann temperature of the ice-water system was found to amount , which is far below the temperature of homogeneous freezing. The Kauzmann pressure was found to amount to , suggesting favor of homogeneous freezing on exerting a negative pressure on the liquid. In terms of thermodynamic properties entering the theory, the reason for the negative Kauzmann pressure is the higher mass density of water in comparison to ice at the melting point.

The Influence of Phytoplankton Primary Production on the Cycle of Biogenic Elements in the Coastal Waters off Sevastopol, Black Sea

The phytoplankton primary production and the biogenic elements content of the coastal waters off Sevastopol have been studied as a result of 2-year monitoring. It has been found that mineral phosphorus is a key factor of chemical limitation of the production processes. During primary production of organic matter, the habitat conditions for phytoplankton in the photic layer are in accordance with the Le Chatelier–Braun principle of negative feedback.

A Homeopathy Model in the Light of Hahnemann’s Pristine Idea

The well-known definition of disease, which Samuel Hahnemann presented while making a challenge to provide a tentative theory for his new science and art of healing, is used as a starting point for the model. The biochemical equilibrium is used for a demonstration of the Le Chatelier-Braun principle and/or the Guldberg–Waage Law in order to clarify the principles and to explain the well-known “Law of Similar”. It is shown that a high dilution accompanied by succession is required to release the remedies to their constituent molecular species in order to increase their “vital energy” when taking part in the overall complex biochemical equilibrium that is essential for healing. In addition, it is revealed that, in principle, a single remedy constituent molecular species, when it is in excess, as well as satisfying the dynamic equilibrium, can shift this biochemical equilibrium and trigger the healing process.

A Homeopathy Model in the Light of Hahnemann’s Pristine Idea

The well-known definition of disease, which Samuel Hahnemann presented while making a challenge to provide a tentative theory for his new science and art of healing, is used as a starting point for the model. The biochemical equilibrium is used for a demonstration of the Le Chatelier–Braun principle and/or the Guldberg–Waage Law in order to clarify the principles and to explain the well-known “Law of Similar”. It is shown that a high dilution accompanied by succussion is required to release the remedies to their constituent molecular species in order to increase their “vital energy” when taking part in the overall complex biochemical equilibrium that is essential for healing. In addition, it is revealed that, in principle, a single remedy constituent molecular species, when it is in excess, as well as satisfying the dynamic equilibrium, can shift this biochemical equilibrium and trigger the healing process.

The phase space interpretation of the Le Chatelier-Braun principle and its generalization as a principle of natural philosophy

The phase space interpretation of the Le Chatelier-Braun principle and its generalization as a principle of natural philosophy

Applying the expanded Le Chatelier-Braun principle to carbon oxidation in converter baths. 1. Stochastic structure of the harmonic series in the fluctuation of the variable oxidation component

In converter baths, the arrhythmic behavior in the oxidation of carbon and the probability of surges may be assessed from the dispersion of the fluctuation in the variable component of carbon’s oxidation rate ΔVC during intense oxidation. In such conditions, ΔVC may be regarded as a weakly ergodic random process. That approach permits investigation of the frequency series in the fluctuation of the random component ΔVC. It is represented by a practically continuous frequency sequence corresponding to the structural components of the converter process.

Le Chatelier-Braun principle

Le Chatelier-Braun principle was modified for calculating the rate of free energy production [RFEP] in the flow of poly vinyl chloride (PVC) plastisol. At low-to-intermediate shear rate, viscosity decreases with increasing shear rate and reaches a minimum. The behavior was explained by the dominance of the rheological effect at the lower shear rates and that of the thermodynamic effect at the higher shear rates. In the former, viscous resistance was reduced by stress-induced phase separation into an immobilized layer and a mobile phase. In the latter the RFEP increases, reaching a maximum at the minimum viscosity. In the pseudo-plastic flow region, the flow is stable and the RFEP is negative. At shear rates higher than those at minimum viscosity, the immobilized layer dilates and then fractures when the stress becomes higher than the strength of the layer. Both dilatation and fracture are manifestations of flow instability and RFEP is positive, indicating insufficient resistance against failure of the immobilized layer. At super high shear rates, a plug flow takes place with a very thin layer of plasticizer lubricating at the capillary wall. Pseudo-plastic behavior may be explained by two different mechanisms. One is that a very small amount of particles are present in the lubricating layer. The particles are expelled from the layer with the increase in shear rate. The other possibility is that even though the lubricating layer consists of pure plasticizer, the layer increases in thickness in order to avoid excessive secondary flow such as eddy formation.

Backward jump continuous-time random walk: An application to market trading

The backward jump modification of the continuous-time random walk model or the version of the model driven by the negative feedback was herein derived for spatiotemporal continuum in the context of a share price evolution on a stock exchange. In the frame of the model, we described stochastic evolution of a typical share price on a stock exchange with a moderate liquidity within a high-frequency time scale. The model was validated by satisfactory agreement of the theoretical velocity autocorrelation function with its empirical counterpart obtained for the continuous quotation. This agreement is mainly a result of a sharp backward correlation found and considered in this article. This correlation is a reminiscence of such a bid-ask bounce phenomenon where backward price jump has the same or almost the same length as preceding jump. We suggested that this correlation dominated the dynamics of the stock market with moderate liquidity. Although assumptions of the model were inspired by the market high-frequency empirical data, its potential applications extend beyond the financial market, for instance, to the field covered by the Le Chatelier-Braun principle of contrariness.

A nonmolecular derivation of Maxwell’s thermal-creep boundary condition in gases and liquids via application of the LeChatelier–Braun principle to Maxwell’s thermal stress

According to the LeChatelier–Braun principle, when a closed quiescent system initially in an equilibrium or unstressed steady state is subjected to an externally imposed “stress” it responds in a manner tending to alleviate that stress. Use of this entropically based qualitative rule, in combination with the notion of Maxwell thermal stresses existing in nonisothermal gases and liquids, enables one to (i) derive Maxwell’s thermal-creep boundary condition prevailing at the boundary between a solid and a fluid (either gas or liquid) and (ii) rationalize the phenomenon of thermophoresis in liquids, for which, in contrast with the case of gases, an elementary explanation is currently lacking. These two objectives are achieved by quantitatively interpreting the heretofore qualitative LeChatelier–Braun notion of stress in the present context as being the fluid’s stress tensor, the latter including Maxwell’s thermal stress. In effect, thermophoretic particle motion is interpreted as the manifestation of the fluid’s attempt to expel the particle from its interior so as to alleviate the thermal stress that would otherwise ensue were the particle to remain at rest (thus obeying the traditional no slip rather than thermal-creep boundary condition) following its introduction into the previously stress-free quiescent fluid. With Kn the Knudsen number in the case of rarefied gases, Maxwell’s thermal stress constitutes a noncontinuum phenomenon of O(Kn2), whereas his thermal-creep phenomenon constitutes a continuum phenomenon of O(Kn). That these two phenomena can, nevertheless, be proved to be synonymous (in the sense, so to speak, of being two sides of the same coin), as is done in the present paper, supports the “ghost effect” findings of Sone [Y. Sone, “Flows induced by temperature fields in a rarefied gas and their ghost effect on the behavior of a gas in the continuum limit,” Annu. Rev. Fluid Mech 32, 779 (2000)], which, philosophically, imply the artificiality of the distinction currently existing between continuum- and noncontinuum-level phenomena.

Non-Diversifiable Risk and Quantity Discounts in Taiwanese Urban Land Markets

Land assembly and subdivision costs are negligible in residential land markets in certain land readjustment districts of Taichung City, Taiwan. Our empirical investigation finds evidence for significant quantity discounts in the case of land sales in these post-consolidated markets. This finding contradicts the prediction of the Le Chatelier-Braun Principle put forward in the work of Lin and Evans (2000). Moreover, the discounts are larger for land sales zoned in R-2 districts than those zoned in R-1 districts. These results are consistent with Brownstone and De Vany's (1991) non-diversifiable risk hypothesis.

Two characterizations of inverse-positive matrices: the Hawkins-Simon condition and the Le Chatelier-Braun principle

It is shown that (a weak version of) the Hawkins-Simon condition is satisfied by any real square matrix which is inverse-positive after a suitable permutation of columns or rows. One more characterization of inverse-positive matrices is given converning the Le Chatelier-Braun principle. The proofs are all simple and elementary. 

Identifying the adaptive mechanism in globular proteins: Fluctuations in densely packed regions manipulate flexible parts

A low-resolution structural model based on the packing geometry of α-carbons is utilized to establish a connection between the flexible and rigid parts of a folded protein. The former commonly recognizes a complementing molecule for making a complex, while the latter manipulates the necessary conformational change for binding. We attempt analytically to distinguish this control architecture that intrinsically exists in globular proteins. First with two-dimensional simple models, then for a native protein, bovine pancreatic trypsin inhibitor, we explicitly demonstrate that inserting fluctuations in tertiary contacts supported by the stable core, one can regulate the displacement of residues on loop regions. The positional fluctuations of the flexible regions are annihilated by the rest of the protein in conformity with the Le Chatelier–Braun principle. The results indicate that the distortion of the principal nonbonded contacts between highly packed residues is accompanied by that of the slavery fluctuations that are widely distributed over the native structure. These positional arrangements do not appear in a reciprocal relation between a perturbation and the associated response; the effect of a movement of residue i on residue j is not equal to that of the same movement of residue j on residue i.

Some special features of the le chatelier-braun principle

The relaxation reaction of a system that follows from the Le Chatelier-Braun principle and weakens the result of an external influence turns out to be more intense under a complex action. A method for quantitative determination of the weakening effect for simple and complex actions is suggested.

Broken symmetry phase transition in solid p-H 2, o-D 2 and HD: crystal field effects

We report the effect of the crystal field (CF) on the broken symmetry phase transition (BSP) in solid parahydrogen, orthodeuterium, and hydrogen deuteride. The CF was calculated taking into account a distortion from the ideal HCP structure. We find that, in addition to the molecular field generated by the coupling terms in the intermolecular potential, the Hamiltonian of the system contains a crystal-field term, originating from single-molecular terms in the intermolecular potential. Ignoring the CF is the main cause of the systematic underestimation of the transition pressure, characteristic of published theories of the BSP transition. The distortion of the lattice that gives rise to the negative CF in response to the applied pressure is in accord with the general Le Chatelier–Braun principle.

A Generalized Evolution Criterion in Nonequilibrium Convective Systems

A general evolution criterion, applicable to transport processes such as the conduction of heat and mass diffusion, is obtained as a direct version of the Le Chatelier-Braun principle for stationary states. The present theory is not based on any radical departure from the conventional one. The generalized theory is made determinate by proposing the balance equations for extensive thermodynamic variables which will reflect the character of convective systems under the assumption of local equilibrium. As a consequence of the introduction of source terms in the balance equations, there appear additional terms in the expression of the local entropy production, which are bilinear in terms of the intensive variables and the sources. In the present paper, we show that we can construct a dissipation function for such general cases, in which the premises of the Glansdorff-Prigogine theory are accumulated. The new dissipation function permits us to formulate a generalized evolution criterion for convective systems.

Subsonic-supersonic condition for shocks

The necessary conditions for stability of a shock, that the shock travel with supersonic velocity with respect to the medium ahead and with subsonic velocity with respect to the medium behind, are shown to be implied by the second law of thermodynamics for very general classes of viscous, heat-conducting fluids; the Weyl conditions are not invoked. The results are shown to be also compatible with the Le Chatelier–Braun principle. They further imply that under certain conditions it is not thermodynamically permissible to assume the existence of a shock transition layer in which entropy production is due to heat conduction alone.

Coordination complexes and equilibrium

The results of this demonstration are explained in terms of equilibrium, Le Chatelier-Braun's principle, and coordination complex formation.