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In the present study, nickel and copper fast diffusion in silicon is investigated in the framework of the cBΩ thermodynamic model, which connects point defect parameters with the bulk elastic and expansion properties. All the calculated point defect thermodynamic properties (activation Gibbs free energy, activation enthalpy, activation entropy, and activation volume) exhibit temperature dependence due to the non-linear anharmonic behavior of the isothermal bulk modulus of Si. Calculated activation enthalpies (0.15–0.16 eV for Ni and 0.17–0.19 eV for Cu) are in agreement with the reported experimental results. Small values of calculated activation volumes for both dopants (∼4% of the mean atomic volume) are consistent with the interstitial diffusion of Ni and Cu in Si. [ABSTRACT FROM AUTHOR]

Interactions between a protein and a ligand are often accompanied by a redistribution of the population of thermally accessible conformations. This dynamic response of the protein's functional energy landscape enables a protein to modulate binding affinities and control binding sensitivity to ligand concentration. In this paper, we investigate the structural origins of binding affinity and allosteric cooperativity of binding two Ca2+ ions to each domain of Calmodulin (CaM) through simulations of a simple coarse-grained model. In this model, the protein's conformational transitions between open and closed conformational ensembles are simulated explicitly and ligand binding and unbinding are treated implicitly within the grand canonical ensemble. Ligand binding is cooperative because the binding sites are coupled through a shift in the dominant conformational ensemble upon binding. The classic Monod-Wyman-Changeux model of allostery with appropriate binding free energies to the open and closed ensembles accurately describes the simulated binding thermodynamics. The simulations predict that the two domains of CaM have distinct binding affinity and cooperativity. In particular, the C-terminal domain binds Ca2+ with higher affinity and greater cooperativity than the N-terminal domain. From a structural point of view, the affinity of an individual binding loop depends sensitively on the loop's structural compatibility with the ligand in the bound ensemble, as well as the conformational flexibility of the binding site in the unbound ensemble. [ABSTRACT FROM AUTHOR]

Insertion of a solute into a vessel comprising biopolymers is a fundamental function in a biological system. The entropy originating from the translational displacement of solvent particles plays an essential role in the insertion. Here we study the dynamics of entropic insertion of a large spherical solute into a cylindrical vessel. The solute and the vessel are immersed in small spheres forming the solvent. We develop a theoretical method formulated using the Fokker-Planck equation. The spatial distribution of solute-vessel entropic potential, which is calculated by the three-dimensional integral equation theory combined with rigid-body models, serves as input data. The key quantity analyzed is the density of the probability of finding the solute at any position at any time. It is found that the solute is inserted along the central axis of the vessel cavity and trapped at a position where the entropic potential takes a local minimum value. The solute keeps being trapped without touching the vessel inner surface. In a significantly long time τ, the solute transfers to the position in contact with the vessel bottom possessing the global potential minimum along the central axis. As the solute size increases, τ becomes remarkably longer. We also discuss the relevance of our result to the functional expression of a chaperonin/cochaperonin in the assistance of protein folding. [ABSTRACT FROM AUTHOR]

Calmodulin (CaM) is a ubiquitous Ca2+-binding protein consisting of two structurally similar domains with distinct stabilities, binding affinities, and flexibilities. We present coarse grained simulations that suggest that the mechanism for the domain's allosteric transitions between the open and closed conformations depends on subtle differences in the folded state topology of the two domains. Throughout a wide temperature range, the simulated transition mechanism of the N-terminal domain (nCaM) follows a two-state transition mechanism while domain opening in the C-terminal domain (cCaM) involves unfolding and refolding of the tertiary structure. The appearance of the unfolded intermediate occurs at a higher temperature in nCaM than it does in cCaM consistent with nCaM's higher thermal stability. Under approximate physiological conditions, the simulated unfolded state population of cCaM accounts for 10% of the population with nearly all of the sampled transitions (approximately 95%) unfolding and refolding during the conformational change. Transient unfolding significantly slows the domain opening and closing rates of cCaM, which can potentially influence its Ca2+-binding mechanism. [ABSTRACT FROM AUTHOR]

We investigate which terms in Reduced-Dimensionality Semiclassical Transition State Theory (RD SCTST) contribute most significantly in rate constant calculations of hydrogen extraction and exchange reactions of hydrocarbons.We also investigate the importance of deep tunneling corrections to the theory. In addition, we introduce a novel formulation of the theory in Jacobi coordinates. For the reactions of H atoms with methane, ethane, and cyclopropane, we find that a one-dimensional (1-D) version of the theory without deep tunneling corrections compares well with 2-D SCTST results and accurate quantum scattering results. For the "heavy-light-heavy" H atom exchange reaction between CH3 and CH4, deep tunneling corrections are needed to yield 1-D results that compare well with 2-D results. The finding that accurate rate constants can be obtained from derivatives of the potential along only one dimension further validates RD SCTST as a computationally efficient yet accurate rate constant theory. [ABSTRACT FROM AUTHOR]

Fundamental understanding of mass transport in solids as a function of temperature is crucial to applications in various all-solid-state ionic devices, including fuel cells, sensors, and batteries. Commonly, electrical properties have been investigated at various temperatures and the activation energy computed from the slope of the Arrhenius plot. Changes in the activation energy as a function of chemical composition induced by chemical substitution/doping are used as a tool to understand defects and transport phenomena in solids. Meyer and Neldel found that the energy of activation can appear in the pre-exponential factor, A, in a manner that cancels the traditional activation energy factor in the Arrhenius equation at a certain transition temperature. This pre-exponential activation energy is manifested as an entropy and designated as the entropy of activation and the phenomenon is called as the Meyer-Neldel rule (MNR). Entropy of activation has been associated with the stochastic nature of the barrier heights, which is then reflected in the randomness of the jump frequency of the charge carriers. Many of the theoretical approaches developed to study this phenomenon utilize a Boltzmann distribution of the barrier heights; we have used a classical Bose-Einstein (BE) distribution in which, at the transition temperature, a large number of very low-energy barriers appear as a "condensate" minimizing the role of the activation energy. The advantage of using the BE statistics over the Boltzmann statistics lies in the fact that the former naturally contains a transition temperature. Using this model, we have further analyzed the entropy of several Li-stuffed garnet-type solid electrolytes, which are being considered for all-solid-state Li batteries and as well as several other fast ion-conducting solids. [ABSTRACT FROM AUTHOR]

Insertion and release of a solute into and from a vessel comprising biopolymers is a fundamental function in a biological system. A typical example is found in a multidrug efflux transporter. 'Multidrug efflux' signifies that solutes such as drug molecules with diverse properties can be handled. In our view, the mechanism of the multidrug efflux is not chemically specific but rather has to be based on a physical factor. In earlier works, we showed that the spatial distribution of the solute-vessel potential of mean force (PMF) induced by the solvent plays imperative roles in the insertion/release process. The PMF can be decomposed into the energetic and entropic components. The entropic component, which originates from the translational displacement of solvent molecules, is rather insensitive to the solute-solvent and vessel inner surface-solvent affinities. This feature is not shared with the energetic component. When the vessel inner surface is neither solvophobic nor solvophilic, the solvents within the vessel cavity and in the bulk offer almost the same environment to any solute with solvophobicity or solvophilicity, and the energetic component becomes much smaller than the entropic component (i.e., the latter predominates over the former). Our idea is that the multidrug efflux can be realized if the insertion/release process is accomplished by the entropic component exhibiting the insensitivity to the solute properties. However, we have recently argued that the entropic release of the solute is not feasible as long as the vessel geometry is fixed. Here we consider a model of TolC, a cylindrical vessel possessing an entrance at one end and an exit at the other end for the solute. The spatial distribution of the PMF is calculated by employing the three-dimensional integral equation theory with rigid-body models in which the constituents interact only through hard-body potentials. Since the behavior of these models is purely entropic in origin, our analysis is focused on the entropic component. We show that the entropically inserted solute can be released by a continuous variation of the vessel geometry which forms a time-dependent entropic force continuing to accelerate the solute motion to the exit. Solutes with a wide range of sizes are entropically released using the same vessel-geometry variation. The results obtained are fairly general and also applicable to the efflux pump protein AcrB and ATP-binding cassette transporter. [ABSTRACT FROM AUTHOR]

Kazuo Ishiguro acknowledges the fallibility of the human condition, and herein lies the therapeutic core of his novels. The current study proposes a theoretical approach to Ishiguro's second novel (1989) from an interdisciplinary perspective on the main character's narrative. In the first part, Henry James' interpretation of literature applies to Masuji Ono's totalitarian views to link fiction to real life. The second part discusses the relativity of choices and decisions based on transgenerational ethics as presented in Strauss and Howe's Fourth Turning Theory. The third part focuses on Ono's narrative unreliability as a form of confabulation. Since Ono's recollections often clash with what his family can remember about certain events, the painter may be suffering from the false memory effect as a form of healing old trauma. The last subchapter explains the concept of 'mono no aware' from a scientific perspective. The Japanese understanding of the 'pathos of things' is reflected in the second law of thermodynamics, which stipulates that universal disorder will always increase. While young Ono refuses to accept the floating world, old Ono seeks to make peace with the transitory nature of existence, which is equivalent to accepting the entropy of the Universe. [ABSTRACT FROM AUTHOR]

The aims of this study were firstly to compare the similarity in upper-body muscle activation between the bench press and push-up at similar loads, and secondly to establish a 1-RM prediction equation between the two exercises based upon the load-velocity relationship. Twenty resistance-trained male athletes (age 22.5 ± 5.24 years, body mass 83.7 ± 10.7 kg, body height 1.80 ± 0.06 m) performed push-ups and bench presses with four different loads. Push-ups were performed without a weight vest and with a 10-20-30 kg weight vest. Bench presses were performed at 50-80% of athletes' assumed 1 repetition max (1-RM) in 10 kg steps, while a linear encoder measured performance during the exercises. A load-velocity relationship was established as a product of the load and velocity for the push-up and bench press per participant and the equation was used to establish a predicted 1-RM. Mean muscle activation of eight upper body muscles was recorded for each exercise and each load. The main findings of this study demonstrate an extremely large association between the predicted 1-RM loads performed with the push-up and bench press (r = 0.93) in experienced resistance trained men. Furthermore, most muscles showed similar activations between the two exercises with the different loads except the deltoid and biceps brachii muscles. It may be concluded that it is possible to predict a cross-over 1-RM between the two exercises based upon the load-velocity relationship in each exercise, and that training push-ups largely targets the same muscles as the bench press except the deltoid and biceps muscles. For coaches and athletes, the use of this method is a low cost and time-effective alternative for standard 1-RM bench press testing to predict maximal upper body strength. [ABSTRACT FROM AUTHOR]

Physicochemical parameters, total phenols contents (TPC), and oxidative stabilities at 120–160 °C were evaluated for two monovarietal (Arbequina and Cobrançosa cultivars, cvs.) and one blend extra‐virgin olive oil, confirming the label quality grade and allowing grouping them according to the different TPC (TPC = 88 ± 7, 112 ± 6 and 144 ± 4 mg CAE/kg, for cv. Arbequina, blend and cv. Cobrançosa oils, respectively). The lipid oxidation rate increased with the decrease of the TPC, being Cobrançosa oils (higher TPC) more thermally stable. Kinetic‐thermodynamic parameters were determined using the activated complex/transition‐state theory and the values did not significantly differ for Cobrançosa and blend oils, which had the highest TPC, suggesting a hypothetically threshold saturation of the beneficial effect. Cobrançosa oils had a significant more negative temperature coefficient, higher temperature acceleration factor, greater activation energy and frequency factor, higher positive enthalpy of activation, lower negative entropy of activation, and greater positive Gibbs free energy of activation, probably due to the higher TPC. The results confirmed that lipid oxidation was a nonspontaneous, endothermic, and endergonic process with activated formed complexes structurally more ordered than the reactants. A negative deviation from the Arrhenius behavior was observed for all oils being the super‐Arrhenius behavior more marked for Arbequina oils that had the lowest TPC. Finally, the kinetic‐thermodynamic parameters allowed classifying oils according to the binomial olive cultivar/total phenols level, being the temperature acceleration factor and the Gibbs free energy of activation at 160 °C the most powerful discriminating parameters. [ABSTRACT FROM AUTHOR]

The rate of hydrolysis of hydrolysis of ethyl benzoate were measured volumetric over the temperature range of 200c to 400c.in water-methanol mixture at different composition. The different solvation in initial and transition state is due to decrease in rate with varying the composition of mixture. The influence of solvent on reaction rate was examined in term of activation parameter. The increase in values of DG* and simultaneous depletion in values of DH* and DS* with solvent composition reveals that the reaction is Enthalpy domination and Entropy controlled. The value of iso-kinetic temperature is less than 300 shows the weak interaction between solvent and solute.

Many chemical methods have been developed to favor a particular product in transformations of compounds that have two or more reactive sites. We explored a different approach to site selectivity using vibrational strong coupling (VSC) between a reactant and the vacuum field of a microfluidic optical cavity. Specifically, we studied the reactivity of a compound bearing two possible silyl bond cleavage sites—Si–C and Si–O, respectively—as a function of VSC of three distinct vibrational modes in the dark.The results show that VSC can indeed tilt the reactivity landscape to favor one product over the other.Thermodynamic parameters reveal the presence of a large activation barrier and substantial changes to the activation entropy, confirming the modified chemical landscape under strong coupling. [ABSTRACT FROM AUTHOR]

Abstract The mixture of choline chloride and ethyleneglycol ((1:3) on the molar scale) is first characterized using density, viscosimetry and refractive index measurements, in the temperature range 20–45°C, with controlled amounts of water. Thermodynamic parameters such as the activation entropy, enthalpy and Gibbs energy for the viscous flow are deduced from the data and show that the solvent is highly structured. A protocol to disperse in this solvent 10 nm maghemite nanoparticles previously synthesized in water is described. The good quality of the dispersion is assessed by visual observations, optical microscopy, small angle X-ray scattering (SAXS), magnetization measurements, viscosimetry, and light scattering. The results lead to the description of a local viscosity around the particles, lower than the macroscopic one, that could be the result of the solvent segregation with ethyleneglycol being mostly present in the close vicinity of the particles. Highlights • The complex solvent made of a mixture of ethylene glycol-choline chlorine is characterized (viscosity and density). • The influence of water is examined. • The Eyring model for the molecular flow shows high associativity (H-bonds). • Stable dispersions of magnetic nanoparticles (MNPs) were dispersed in this solvent. • The local viscosity around the NPs is lower than the bulk one. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) are an emerging class of advanced structural alloys under extensive research; yet, the properties of the liquid states of these materials, which are relevant to their processing, have been far less explored. In this work, we utilize ab initio molecular dynamics simulations to investigate the melt properties of a representative HEA—the Cantor alloy—and its derivatives: CrMnFeCoNi, CrFeCoNi, and CrCoNi. The atomic dynamics of these melts at various temperatures are investigated, specifically to analyze their electronic and atomic structures, including charge transfer, pair distribution functions, and short-range order. Results are compared with existing information for the liquids of metallic glasses, which also typically contain multiple principal elements, but retain the amorphous state under moderate to fast cooling rates. The present results provide insights into the structural and bonding factors favoring solidification to single-phase solid solutions in HEAs. [ABSTRACT FROM AUTHOR]

We consider backreacted AdS5 × S5 coupled with Nf massless avors introduced by D7-branes at nonzero temperature. The backreacted geometry is in the Veneziano limit. The temperature of this system is related to the event horizon at rh. Dividing one of the spatial directions into a line segment with length l, we will calculate the holographic entanglement entropy (HEE) between the two subspaces. We study the behavior near the event horizon, and nally nd that there exists con nement/decon nement phase transition phenomenon near the horizon since the difference between the entanglement entropy of the connected minimal surface and the disconnected one changes sign. [ABSTRACT FROM AUTHOR]

The thermodynamic parameters Eact, ΔH≠, ΔS≠, and ΔG≠ for various processes involving antioxidants were calculated using literature kinetic data (k, T). The ΔG≠ values of the antioxidants' processes vary in the range 91.27-116.46 kJmol-1 at 310 K. The similarity of the ΔG≠ values (for all of the antioxidants studied) is supported to be an indication that a common mechanism in the above antioxidant processes may be taking place. A value of about 10-30 kJmol-1 is the activation energy for the diffusion of reactants depending on the reaction and the medium. The energy 92 kJmol-1 is needed for the excitation of O2 from the ground to the first excited state (¹Δg, singlet oxygen). We suggest the same role of the oxidative stress and specifically of singlet oxygen to the processes of antioxidants as in the processes of proteinaceous diseases. We therefore suggest a competition between the various antioxidants and the proteins of proteinaceous diseases in capturing singlet oxygen's empty π* orbital. The concentration of the antioxidants could be a crucial factor for the competition. Also, the structures of the antioxidant molecules play a significant role since the various structures have a different number of regions of high electron density. [ABSTRACT FROM AUTHOR]

Large scale green production of poly(oxymethylene) dimethyl ethers(DMM n ) would be crucial if the diesel-DMM n blends were applied to tackle the worldwide formidable air pollution by particulate matter. Kinetics studies are of great significance among the core challenges for understanding the reaction principles and process design. Kinetic model was developed for the production of DMM n from methylal and trioxane with sulfonic acid-functionalized ionic liquid as catalyst. Reversible reactions of propagation-depolymerization were simultaneously considered with non-equal rate constants for complex sequential reactions. The kinetic model proposed showed good accuracy and consistency for both forward and backward reactions. Activation energies E p were in the range of 35.7 to 39.6 kJ mol −1 for DMM n propagation reactions and 50.8 to 54.7 kJ mol −1 for DMM n decomposition, with the difference of −15.1 kJ mol −1 determined by Arrhenius equation. Entropy of activation, determined by Eyring-Polanyi equation, could make a significant contribution to the Gibbs energy barrier in the DMM n propagation/decomposition. It is interesting that the Schulz-Flory type distribution still could be maintained even the calculated rate constants increased with DMM n chain length. [ABSTRACT FROM AUTHOR]

The rheological properties of nitrocellulose solutions in cyclohexanone in the presence of phthalic and 4-nitrophthalic diester plasticizers were studied by rotational viscometry to reveal a behavior similar to that of Newtonian fluids. The activation parameters of the viscous flow regime were calculated. An influence of nitroplasticizers and dibutyl phthalate on the rheology of nitrocellulose was established. The influence of plasticizers on the mechanical properties of nitrocellulose films was discussed. [ABSTRACT FROM AUTHOR]

Reaction rates of toluene disproportionation (A) and cumene cracking (B) normalized by the number of Brønsted acid sites were analyzed on aluminosilicates. The activation entropy showed linear and compensatory relationship against the activation enthalpy. The slope of entropy-enthalpy plot was in the order of (B) > (A) > small alkane cracking, whereas the intercept on the horizontal axis was in the order of propane and isobutane cracking > linear C4–8 alkanes and iso-pentane cracking > (A) > (B). The former is consistent with the bulkiness of reactant, while the latter is consistent with intrinsic difficulty of formation of intermediate cations. [ABSTRACT FROM AUTHOR]

Transmetalation between Pd(Br)(PhA)(PCyp3)2 (Ph = phenyl, Cyp = cyclopentyl) and Cu(CaHMePhB)(NHC) (NHC = 1,3-bis(2,6-diisopropylphenyl)-imidazolidin-2-ylidene) is an important elementary step in recently reported catalytic cross-coupling reaction by Pd/Cu cooperative system. DFT study discloses that the transmetalation occurs with inversion of the stereochemistry of the CaHMePhB group. In its transition state, the CaHMePhB group has almost planar structure around the Ca atom. That planar geometry is stabilized by conjugation between the π* orbital of the PhB and the 2p orbital of the Ca. Another important factor is activation entropy (ΔS°‡); retention transmetalation occurs through Br-bridging transition state, which is less flexible than that of the inversion transmetalation because of the Br-bridging structure, leading to a smaller activation entropy in the retention transition state than in the inversion transition state. For CaHMeEt group, transmetalation occurs in a retention manner. In the planar CaHMeEt group of the inversion transition state, the Ca 2p orbital cannot find a conjugation partner because of the absence of π-electron system in the CaHMeEt. Transmetalation of CaHMe(CH=CH2) occurs in a retention manner because the vinyl π* is less effective for the conjugation with the Ca 2p because of its higher orbital energy than the Ph π*. The introduction of electronwithdrawing substituent on the PhB is favorable for inversion transmetalation. These results suggest that the stereochemistry of the Ca atom in transmetalation can be controlled by electronic effect of the CaHMeR (R = phenyl, vinyl, or alkyl) and sizes of the substituent and ligand. [ABSTRACT FROM AUTHOR]

Effects of Cu, Mn, Al, Ti, Mo on generalized stacking fault energies, Rice-criterion ductilities, and twinabilities of CoCrFeNi-based face-centered cubic high entropy alloys were investigated using density functional theory calculations. The calculated barrier energies and twinnabilities revealed that the addition of Ti or Mo increased the tendency of dislocation glide and deformation twinning, while addition of Mn, Cu and relatively high amount of Al facilitated dislocation gliding and martensitic transformation. Low amount of Al resulted in only dislocation gliding. Furthermore, the addition of Mn and Cu increased the calculated Rice-criterion ductility while other elements decreased it. [ABSTRACT FROM AUTHOR]

This paper presents a three-dimensional numerical modeling of a PEM fuel cell with tree-like flow field channels. Four different tree-like configurations are considered for the study based on a statistical analysis of the veins of the leaves of different trees. The number of bifurcations of the vein and their inclination are considered as parameters for the characterization. Four different configurations are the most recurrent, corresponding to one level of bifurcation at 37° and 74° and two levels of bifurcation at 37° and 74°. The model considers a complete solution of the mass, momentum, energy, and electrochemical equations. An entropy generation analysis is developed as a post processing once the solution of the models is obtained. Because new geometries for the channel configuration in the bipolar plates are introduced, special attention is considered for the entropy generation due to mass flow. Results indicate that the configuration with two levels of bifurcation at 37° is efficient at removing water from the cathode channels, resulting in a good current density production. In addition, a better performance of the PEM fuel cell (higher current density production and lower entropy production) is obtained by increasing the number of bifurcations. [ABSTRACT FROM AUTHOR]

The release of NO by [Fe(NO)(Et2NpyS4)], where (Et2NpyS4)2− = 2,6-bis(2-mercaptophenylthiomethyl)-4-substituted pyridine(2-), has been studied in the absence and presence of a trapping agent. The results show that [Fe(NO)(Et2NpyS4)] releases NO spontaneously in solution with a slow rate,k-NO = 1.7 × 10−4s−1at 23 °C, in a reversible reaction. NO release becomes faster when the reaction intermediate [Fe(Et2 NpyS4)] was trapped by CO, thereby preventing the back reaction. The release of NO was studied as a function of CO concentration and temperature. The reported activation parameters, especially the positive activation entropy values for the release of NO, favor the operation of a dissociative interchange (Id) mechanism. Thus, [Fe(NO)(Et2NpyS4)] can serve as a NO deliverer. [ABSTRACT FROM PUBLISHER]

This paper researches on methods of the color image segmentation method of Lingwu long jujubes based on the maximum entropy to achieve the accuracy of image segmentation and improve accuracy of machine recognition. According to law between the color of Lingwu long jujubes and characteristic of environment, starting from the hue information, this paper is first to explore the difference between the hue of Lingwu long jujubes and the environment which it lives and then use maximum entropy to segment image. It finds optimal threshold by mathematical criterion judging the accuracy of image segmentation. The method of pre-processing of image is mean filter firstly. Then, it extracts hue information of true color image and uses maximum entropy for image segmentation, judging accuracy of image segmentation by segmentation area whether it is in accordance with the 3σ principle. Mathematical morphology is used for smoothing image and eliminating small holes. Finally, segmented image will be obtained through labeling the image by using methods of labeled image and using characteristic parameters for extracting feature. By comparing the segmentation effect with artificial method of the 30 Lingwu long jujubes images, it proves that the color image segmentation method of Lingwu long jujubes based on the maximum entropy has good effect to extract the object region. The accuracy of segmentation rate is up to 89.60%. The time that the algorithm run is 1.3132 s. [ABSTRACT FROM AUTHOR]

The change of zero order entropy is studied over different strategies of grammar production rule selection. The two major rules are distinguished: transformations leaving the message size intact and substitution functions changing the message size. Relations for zero order entropy changes were derived for both cases and conditions under which the entropy decreases were described. In this article, several different greedy strategies reducing zero order entropy, as well as message sizes are summarized, and the new strategy MinEnt is proposed. The resulting evolution of the zero order entropy is compared with a strategy of selecting the most frequent digram used in the Re-Pair algorithm. [ABSTRACT FROM AUTHOR]

Oxidation is one of the most important industrial reactions as it yields useful products. Literature survey indicates the use of several organic oxidants for the oxidation of alcohols to the corresponding carbonyl compounds but inorganic oxidants have rarely been used. Further, the kinetic and thermodynamic aspects of oxidation of perfumery alcohols have not been investigated. In this paper, we report the kinetic studies of oxidation of acyclic primary perfumery alcohols, Nerol, Citronellol and Geraniol, to aldehydes using K2S2O8 and KIO4 in acidic medium. The oxidation was carried out under first order kinetic conditions with respect to the inorganic oxidants. The progress of reaction was monitored by iodometric estimation of the unreacted oxidants at regular time interval during the course of the reaction. The reaction was found to be independent of ionic strength (μ).The thermodynamic activation parameters have been determined from the variation of oxidation rate with temperature. Suitable reactionmechanism have been suggested for the oxidation of perfumery alcohols. [ABSTRACT FROM AUTHOR]

The thermodynamic parameters Eact, ΔH≠, ΔS≠, and ΔG≠ for various processes involving antioxidants were calculated using literature kinetic data (k, T). The ΔG≠ values of the antioxidants’ processes vary in the range 91.27–116.46 kJmol−1 at 310 K. The similarity of the ΔG≠ values (for all of the antioxidants studied) is supported to be an indication that a common mechanism in the above antioxidant processes may be taking place. A value of about 10–30 kJmol−1 is the activation energy for the diffusion of reactants depending on the reaction and the medium. The energy 92 kJmol−1 is needed for the excitation of O2 from the ground to the first excited state (1Δg, singlet oxygen). We suggest the same role of the oxidative stress and specifically of singlet oxygen to the processes of antioxidants as in the processes of proteinaceous diseases. We therefore suggest a competition between the various antioxidants and the proteins of proteinaceous diseases in capturing singlet oxygen’s empty π* orbital. The concentration of the antioxidants could be a crucial factor for the competition. Also, the structures of the antioxidant molecules play a significant role since the various structures have a different number of regions of high electron density.

Experiments on aqueous suspensions of Fe 2 O 3 particles indicated that the viscosity increased with temperature rather than decreased as is usual and, in terms of the Arrhenius law, the activation energy appeared to be negative. Results were interpreted in terms of an activation energy in which the activation entropy becomes important. The energy required for flow is partially used to break up the colloidal structure of the suspensions and as the structure becomes more stable at higher temperatures, the viscosity increases. Results can be interpreted in terms of a kinetic equation having positive valued activation enthalpies together with negative valued activation entropies. [ABSTRACT FROM AUTHOR]

We have analyzed the effects of different native membrane lipid composition on the thermodynamic properties of the Na+-K+-ATPase in different epithelia from the gilthead seabream Sparus aurata. Thermodynamic parameters of activation for the Na+-K+-ATPase, as well as contents of lipid classes and fatty acids from polar lipids were determined for gill epithelia and enterocytes isolated from pyloric caeca, anterior intestine and posterior intestine. Arrhenius analyses of control animals revealed differences in thermal discontinuity values (Td) and activation energies determined at both sides of Td between intestinal and gill epithelia. Eyring plots disclosed important differences in enthalpy of activation (ΔH‡) and entropy of activation (ΔS‡) between enterocytes and branchial cells. Induction of n-3 LCPUFA deficiency dramatically altered membrane lipid composition in enterocytes, being the most dramatic changes the increase in 18:1n-9 (oleic acid) and the reduction of n-3 LCPUFA (mainly DHA, docosahexaenoic acid). Strikingly, branchial cells were much more resistant to diet-induced lipid alterations than enterocytes, indicating the existence of potent lipostatic mechanisms preserving membrane lipid matrix in gill epithelia. Paralleling lipid alterations, values of Ea1, ΔH‡ and ΔS‡ for the Na+-K+-ATPase were all increased, while Td values vanished, in LCPUFA deficient enterocytes. In turn, Differences in thermodynamic parameters were highly correlated with specific changes in fatty acids, but not with individual lipid classes including cholesterol in vivo. Thus, Td was positively related to 18:1n-9 and negatively to DHA. Td, Ea1 and ΔH‡ were exponentially related to DHA/18:1n-9 ratio. The exponential nature of these relationships highlights the strong impact of subtle changes in the contents of oleic acid and DHA in setting the thermodynamic properties of epithelial Na+-K+-ATPase in vivo. The effects are consistent with physical effects on the lipid membrane surrounding the enzyme as well as with direct interactions with the Na+-K+-ATPase. [ABSTRACT FROM AUTHOR]

The density and viscosity of the pure monoethylethanolamine (EMEA), diethylethanolamine (DEEA), H 2 O components and the binary EMEA (1) +DEEA (2) and EMEA (1) +H 2 O (2) mixtures were measured from (293.15–333.15) K. The physical and thermodynamic properties of excess molar volume ( V E ), thermal expansion coefficient (α), viscosity deviation ( Δh ), activation enthalpy (Δ H ), activation entropy (Δ S ) and activation molar Gibbs free energy (Δ G ) were calculated. The density and viscosity of the pure components as well as the binary mixtures decreased with temperature increasing. The density and viscosity of EMEA, DEEA and H 2 O followed the orders of H 2 O > EMEA > DEEA and EMEA > DEEA > H 2 O, respectively. The density and viscosity decreased with DEEA concentration increasing for EMEA (1) +DEEA (2). In EMEA (1) +H 2 O (2), the density increased with H 2 O concentration increasing, while the viscosity increased and then decreased with H 2 O concentration increasing. [ABSTRACT FROM AUTHOR]

We derive thermodynamic functionals for spatially inhomogeneous magnetization on a torus in the context of an Ising spin lattice model. We calculate the corresponding free energy and pressure (by applying an appropriate external field using a quadratic Kac potential) and show that they are related via a modified Legendre transform. The local properties of the infinite volume Gibbs measure, related to whether a macroscopic configuration is realized as a homogeneous state or as a mixture of pure states, are also studied by constructing the corresponding Young-Gibbs measures. [ABSTRACT FROM AUTHOR]

We report a complete structural and magnetothermodynamic characterization of four samples of the Heusler alloy Ni-Co-Mn-Ga-In, characterized by similar compositions, critical temperatures and high inverse magnetocaloric effect across their metamagnetic transformation, but different transition widths. The object of this study is precisely the sharpness of the martensitic transformation, which plays a key role in the effective use of materials and which has its origin in both intrinsic and extrinsic effects. The influence of the transition width on the magnetocaloric properties has been evaluated by exploiting a phenomenological model of the transformation built through geometrical considerations on the entropy versus temperature curves. A clear result is that a large temperature span of the transformation is unfavourable to the magnetocaloric performance of a material, reducing both isothermal entropy change and adiabatic temperature change obtainable in a given magnetic field and increasing the value of the maximum field needed to fully induce the transformation. The model, which is based on standard magnetometric and conventional calorimetric measurements, turns out to be a convenient tool for the determination of the optimum values of transformation temperature span in a trade-off between sheer performance and amplitude of the operating range of a material. [ABSTRACT FROM AUTHOR]

The thermodynamics of insertion of a protein in a membrane depends on the fine interplay between backbone and side-chain contributions interacting with the lipid environment. Using computer simulations, we probe how different descriptions of the backbone glycyl unit affect the thermodynamics of insertion of individual residues, dipeptides, and entire transmembrane helices. Due to the lack of reference data, we first introduce an efficient methodology to estimate atomistic potential of mean force (PMF) curves from a series of representative and uncorrelated coarse-grained (CG) snapshots. We find strong discrepancies between two CG models, Martini and PLUM, against reference atomistic PMFs and experiments. Atomistic simulations suggest a weak free energy of insertion between water and a POPC membrane for the glycyl unit, in overall agreement with experimental results despite severe assumptions in our calculations. We show that refining the backbone contribution in PLUM significantly improves the PMF of insertion of the WALP16 transmembrane peptide. An improper balance between the glycyl backbone and the attached side chain will lead to energetic artifacts, rationalizing Martini's overstabilization of WALP's adsorbed interfacial state. It illustrates difficulties associated with free-energy-based parametrizations of single-residue models, as the relevant free energy of partitioning used for force-field parametrization does not arise from the entire residue but rather the solvent-accessible chemical groups. [ABSTRACT FROM AUTHOR]

Tricyclo-DNA (tcDNA) is a sugar-modified analogue of DNA currently tested for the treatment of Duchenne muscular dystrophy in an antisense approach. Tandem mass spectrometry plays a key role in modern medical diagnostics and has become a widespread technique for the structure elucidation and quantification of antisense oligonucleotides. Herein, mechanistic aspects of the fragmentation of tcDNA are discussed, which lay the basis for reliable sequencing and quantification of the antisense oligonucleotide. Excellent selectivity of tcDNA for complementary RNA is demonstrated in direct competition experiments. Moreover, the kinetic stability and fragmentation pattern of matched and mismatched tcDNA heteroduplexes were investigated and compared with non-modified DNA and RNA duplexes. Although the separation of the constituting strands is the entropy-favored fragmentation pathway of all nucleic acid duplexes, it was found to be only a minor pathway of tcDNA duplexes. The modified hybrid duplexes preferentially undergo neutral base loss and backbone cleavage. This difference is due to the low activation entropy for the strand dissociation of modified duplexes that arises from the conformational constraint of the tc-sugar-moiety. The low activation entropy results in a relatively high free activation enthalpy for the dissociation comparable to the free activation enthalpy of the alternative reaction pathway, the release of a nucleobase. The gas-phase behavior of tcDNA duplexes illustrates the impact of the activation entropy on the fragmentation kinetics and suggests that tandem mass spectrometric experiments are not suited to determine the relative stability of different types of nucleic acid duplexes. [ABSTRACT FROM AUTHOR]

A series of SrBaBiBO solid solutions ( x = 0-1) have been synthesized by crystallization from glass ceramics. The crystal structures of solid solutions at x = 0.65 and x = 1 were solved by direct methods of X-ray diffraction from single crystal data and refined in a reduced cell ( $${a_{Ba}}{\kern 1pt} = {a_{Sr}}/\sqrt 3 $$ ) relative to SrBiBO in the same space group P6. Using the Rietveld method, the phase transition range at x = 0.65-0.70 with a reduction of the unit cell has been revealed. As was shown by method of high-temperature powder X-ray diffraction, the solid solutions demonstrated an anisotropic thermal expansion (TE) upon heating in air. [ABSTRACT FROM AUTHOR]

This report examines the interpretation of the Graph Derivative Indices (GDIs) from three different perspectives (i.e., in structural, steric and electronic terms). It is found that the individual vertex frequencies may be expressed in terms of the geometrical and electronic reactivity of the atoms and bonds, respectively. On the other hand, it is demonstrated that the GDIs are sensitive to progressive structural modifications in terms of: size, ramifications, electronic richness, conjugation effects and molecular symmetry. Moreover, it is observed that the GDIs quantify the interaction capacity among molecules and codify information on the activation entropy. A structure property relationship study reveals that there exists a direct correspondence between the individual frequencies of atoms and Hückel's Free Valence, as well as between the atomic GDIs and the chemical shift in NMR, which collectively validates the theory that these indices codify steric and electronic information of the atoms in a molecule. Taking in consideration the regularity and coherence found in experiments performed with the GDIs, it is possible to say that GDIs possess plausible interpretation in structural and physicochemical terms. [ABSTRACT FROM AUTHOR]

The organic Rankine cycle (ORC) offers great potential for waste heat recovery and use of low-temperature sources for power generation. However, the ORC thermal efficiency is limited by the relatively low-temperature level, and it is, therefore, of major importance to design ORC components with high efficiencies and minimized losses. The use of organic fluids creates new challenges for turbine design, due to dense gas behavior and the low speed of sound. The design and performance predictions for steam and gas turbines have been initially based on measurements and numerical simulations of flow through two-dimensional cascades of blades. In case of ORC turbines and related fluids, such an approach requires the use of a specially designed dosed cascade wind tunnel. In this contribution the design and process engineering of a continuous running wind tunnel for organic vapors is presented. The wind tunnel can be operated with heavy weight organic working fluids within a broad range of pressure and temperature levels. For this reason, the use of classical design rules for atmospheric wind tunnels is limited. The thermodynamic cycle process in the closed wind tunnel is modeled, and simulated by means of a professional power plant analysis tool, including a database for the ORC fluid properties under consideration. The wind tunnel is designed as a pressure vessel system and this leads to significant challenges particular for the employed wide angle diffuser, settling chamber, and nozzle. Detailed computational fluid dynamics (CFD) was performed in order to optimize the important wind tunnel sections. [ABSTRACT FROM AUTHOR]

The main concern of the present article is to study steady magnetohydrodynamics (MHD) flow, heat transfer and entropy generation past a permeable rotating disk using a semi numerical/analytical method named Homotopy Analysis Method (HAM). The results of the present study are compared with numerical quadrature solutions employing a shooting technique with excellent correlation in special cases. The entropy generation equation is derived as a function of velocity, temperature and concentration gradients. Effects of flow physical parameters including magnetic interaction parameter, suction parameter, Prandtl number, Schmidt number, Soret and Dufour number on the fluid velocity, temperature and concentration distributions as well as entropy generation number are analysed and discussed in detail. Results show that increasing the Soret number or decreasing the Dufour number tends to decrease the temperature distribution while the concentration distribution is enhanced. The averaged entropy generation number increases with increasing magnetic interaction parameter, suction parameter, Prandtl number, and Schmidt number. [ABSTRACT FROM AUTHOR]

Aiming to solve the problem of spontaneous combustion on titanium via electrospark deposition (ESD), two AlCoCuFe-based high-entropy alloys (HEAs), AlCoCuFe- x ( x = CrSiTi, NiSi), were produced by vacuum arc melting as electrodes in ESD process. The thermodynamic analysis of AlCoCuFe-based HEAs were carried out using the concept of mixing enthalpy matrix and a powerful thermodynamic calculation toolbox (HEA-Thermo-Calcu). The microstructure and mechanical properties of the two alloys were investigated. The AlCoCuFeCrSiTi alloy contains a body-centered cubic (BCC) phase and a face-centered cubic (FCC) phase. The AlCoCuFeNiSi alloy is composed of two BCC phases and an FCC phase. Addition of CrSiTi and NiSi to AlCoCuFe-based alloys makes the enthalpy of mixing to be sizably more negative than for the other AlCoCuFe-based HEAs. Notwithstanding the fact that the thermodynamic parameters do not agree with Yang's proposition, the two alloys form simple solid solutions. The electronegativity difference (Δ χ) favors a formation of the solid solution when Δχ ≤ 14.2. The hardness of AlCoCuFe- x ( x = CrSiTi, NiSi) alloys reaches 935 HV and 688 HV, respectively. The yield strength, fracture strength, and ultimate strain of AlCoCuFeNiSi are larger, i.e., 29, 30, and 45%, respectively, than those of the AlCoCuFeCrSiTi alloy. [ABSTRACT FROM AUTHOR]

Several organic oxidants have been used for the oxidation of alcohols to the corresponding carbonyl compounds but inorganic oxidants have rarely been used. The quantitative conversion of alcohols to aldehydes/ketones has been extensively studied but there are few reports of the kinetic investigations of the oxidation of alcohols. The present paper discusses the kinetics of oxidation of 1-hexanol and cyclohexanol using potassium persulphate (K2S2O8) and potassium periodate (KIO4) in acidic medium. 1-hexanol is used in the perfumery industry and cyclohexanol in the manufacture of polymers. Cyclohexanol has an important application as a precursor to nylon. The oxidation was studied under first order kinetic conditions with respect to the oxidant. The progress of the oxidation was monitored by titrimetric estimation of the unreacted oxidants at regular time intervals during the course of the reaction. For both the alcohols, the oxidation rate increased with alcohol concentration but decreased with oxidant concentration. The oxidation rates followed the sequence: 1-hexanol >cyclohexanol. Potassium persulphate was found to be a stronger oxidising agent than potassium periodate for the alcohols under study. The reaction was found to be independent of ionic strength (μ). From the effect of temperature (303-318K) on the rate of oxidation, the various thermodynamic parameters were determined and interpreted in terms of the molecular dynamics of the oxidation process. Suitable reaction mechanisms have been suggested for the oxidation of the alcohols. [ABSTRACT FROM AUTHOR]

Performance of the Reaction Class Transition State Theory (RC-TST) for prediction of rates constants of elementary reactions is examined using data from its previous applications to a number of different reaction classes. The RC-TST theory is taking advantage of the common structure denominator of all reactions in a given family combined with structure activity relationships to provide a rigorous theoretical framework to obtain rate expression of any reaction within a reaction class in a simple and cost-effective manner. This opens the possibility for integrating this methodology with an automated mechanism generator for "on-the-fly" generation of accurate kinetic models of complex reacting systems. [ABSTRACT FROM AUTHOR]

The phosphazene–phosphazane rearrangement of N3P3Cl5O(CH2)2OC(=O)CMe=CH2 (8) has been examined in detail using one and two dimensional NMR (31P, 1H) spectroscopy and mass spectrometry. The mixed phosphazene–phosphazane [NPCl2]2[N((CH2)2OC(=O)CMe=CH2)P(O)Cl] (14), [NPCl2]2[NHP(O)Cl] (13) and a two ring assembly [NPCl2]2[NP(O{(NPCl2)2(N((CH2)2OC(=O)CMe=CH2)P(O)}] (15) have all been detected in the product mixture. The rate of the rearrangement has been measured at five temperatures by 31P and 1H NMR. The reaction is first order in 8 (T1/2 at 111° is 4.65 hours). The activation enthalpy is positive and the activation entropy is negative. A mechanism involving competing intra and inter molecular processes which fits the product distribution and kinetic data has been proposed. Several other methyacrylphosphazenes were examined under the same thermolysis conditions. The rearrangement was observed and the rates obtained in cases where the (CH2)2 spacer unit of the methacrylate was replaced by linear and branched propyl units. The rearrangement was not observed when the methacrylate was appended to a spirocyclic unit, the spacer unit was extended to the n-butyl group and when the methacrylate unit was replaced by a methoxy group. These results are all consistent with the proposed mechanism. This investigation resolves conflicting results previous reported for the rearrangement. [ABSTRACT FROM AUTHOR]

Ce–Fe bimetal oxides with hierarchical pore structure were successfully prepared by a facile approach and used as efficient adsorbent for fluoride removal. The existence of Fe(III) and Ce(IV) in the as-obtained adsorbent was determined by XRD, XPS and HRTEM. The BET surface area of the optimized adsorbent is 164.9 m 2 /g, and the corresponding hierarchical pore size centers at 1.68, 3.41 and 9.54 nm. Batch fluoride adsorption experiments were carried out to investigate the influence of various factors such as adsorbent dosage, contact time, initial solution pH and co-existing anions on the fluoride adsorption. Results show that the maximum adsorption capacity of the optimized adsorbent is as high as 60.97 mg/g. Furthermore, it shows high adsorption capacity over a wide range of pH from 2.9 to 10.1. The adsorption kinetic is well described by the pseudo-second-order model and the fluoride adsorption on the adsorbent agrees well with the Langmuir model. The effects of co-existing anions on the fluoride sorption followed the decreasing order of CO 3 2 − > HCO 3 − > SO 4 2 − > NO 3 − > Cl − , which was found to be closely correlated with the charge–radius ratio values ( z / r ) of the anions. Fluoride adsorption on the Ce–Fe bimetal oxides could be attributed to ion exchange between fluoride and Ce-OH groups. [ABSTRACT FROM AUTHOR]

We present an experimental realization of an autonomous Maxwell's demon, which extracts microscopic information from a system and reduces its entropy by applying feedback. It is based on two capacitively coupled single-electron devices, both integrated on the same electronic circuit. This setup allows a detailed analysis of the thermodynamics of both the demon and the system as well as their mutual information exchange. The operation of the demon is directly observed as a temperature drop in the system. We also observe a simultaneous temperature rise in the demon arising from the thermodynamic cost of generating the mutual information. [ABSTRACT FROM AUTHOR]

The literature data on the substituent influence on the energy, enthalpy, entropy, and free energy of activation for 21 series of organometallic compounds reactions have been analyzed. The activation parameters were first established to depend not only on the classic inductive, resonance, and steric effects but also on the polarizability effect of the substituents (the ion-dipole interaction in the transition state). In certain cases, the polarizability effect has the dominant influence on the considered parameters. [ABSTRACT FROM AUTHOR]

The thermodynamic compensation law describing an empirical linear relationship between activation enthalpy and activation entropy has seldom been validated for amorphous solids. Here molecular dynamics simulations reveal a well-defined enthalpy-entropy compensation rule in a metallic glass (MG) over a wide temperature and stress range, spanning the glass transition induced by temperature and/or stress. Experiments on other MGs reproduce this law, suggesting that it applies universally to amorphous solids, so we extend it from crystals to amorphous solids. In the glassy state, the compensation temperature is found to agree with the thermal glass transition temperature Tg; whereas in the supercooled liquid region, the compensation temperature matches ~ L4Tg, at which the diffusion kinetics start to feel the roughness of the free-energy surface. [ABSTRACT FROM AUTHOR]

Information thermodynamics provides a framework for studying the effect of feedback loops on entropy production. It has enabled the understanding of novel thermodynamic systems such as the information engine, which can be seen as a modern version of "Maxwell's Daemon," whereby a feedback controller processes information gained by measurements in order to extract work. Here, we analyze a simple model of such an engine that uses feedback control based on measurements to obtain negative entropy production. We focus on the distribution and fluctuations of the information obtained by the feedback controller. Significantly, our model allows an analytic treatment for a two-state system with exact calculation of the large deviation rate function. These results suggest an approximate technique for larger systems, which is corroborated by simulation data. [ABSTRACT FROM AUTHOR]

The quantitative conversion of phenols to quinones has been extensively studied and reported but there are few reports about the kinetic and thermodynamic investigations of the oxidation of phenols. In this paper we report the kinetics of the oxidation of the perfumery isomeric phenols, Eugenol and Isoeugenol using KIO4 and K2S2O8 in acidic medium. The oxidation was studied under first order kinetic conditions with respect to the inorganic oxidants and the rate of oxidation of phenols was monitored by iodometric estimation of the unreacted oxidants at regular time intervals. The oxidation rate increased with [phenol] but decreased with increasing [oxidant]. K2SO4 was used to study the effect of ionic strength on the oxidation rate of phenols. The oxidation rates were found to be independent of ionic strength as borne out by the reaction mechanism suggested. The thermodynamic activation parameters were evaluated from the variation of oxidation rate of phenols with temperature (303-318K). The observed negative values of the entropy of activation were ascribed to the formation of a rigid activated complex during the course of the reaction and reorientation of the solvent molecules around the activated complex. This greatly curtailed the degrees of freedom of the reacting system resulting in decrease in entropy. The oxidation rates followed the sequence: Isoeugenol>Eugenol, which has been explained on the basis of isomeric and structural features of the perfumery phenols under study. K2S2O8 was found to be a stronger oxidising agent than KIO4 for oxidation of perfumery phenols in acidic medium. [ABSTRACT FROM AUTHOR]

Biodiesel samples containing rosemary, oregano and basil extracts, free of alcohol, were submitted to oxidative stability tests at temperatures of 110, 115, 120 and 125 °C. The rate constants and enthalpy (ΔH ‡ ), entropy (ΔS ‡ ) and the Gibbs free energy (ΔG ‡ ) in the activated state were determined from the experimentally obtained induction periods for evaluation of efficiency of natural antioxidants. A simplex-centroid mixture design was applied and the predictive equations were optimised simultaneously resulting in values of 85.89 kJ mol − 1 for ΔH ‡ , − 32.25 J K − 1 mol − 1 for ΔS ‡ and 98.48 kJ mol − 1 K − 1 for ΔG ‡ at ratios of 50% rosemary extract, 25% oregano and 25% basil. The results (ΔH ‡ > 0; ΔS ‡ < 0 and ΔG ‡ > 0) showed that, in the presence of natural antioxidants, the oxidation reaction was endothermic and not spontaneous. [ABSTRACT FROM AUTHOR]

In this work, we show that the use of a molecular-field approach and of a closed, effective (even though approximate) form of the orientational partition function, leads to trustworthy predictions of order parameters and other important thermodynamic functions (as heat capacity, orientational internal energy and entropy) of real and/or virtual biaxial nematic mesophases. As a matter of fact, when the partition function Z is explicitly known, all about the thermodynamics of the studied systems becomes in principle accessible, since the thermodynamic functions can be directly calculated through the usual formulas provided by the statistical mechanics. We were successful in obtaining such an approximate expression for Z that works well and allows for almost instantaneous, reliable simulations (it is worthwhile to emphasize that, being available in the present case an analytical expression of Z , the derivatives occurring in the statistical mechanics formulas can be calculated analytically and instantaneously). Several examples of the performances of our approach are presented where, besides the second-rank order parameters, also heat capacities and changes in entropy and internal energy are quantitatively assessed, often for the first time, for the treated cases; moreover, an evaluation of some of the most important fourth-rank order parameters for the treated phases has been carried out. The results are good and our treatment proves to be suitable and promising also for future studies. [ABSTRACT FROM AUTHOR]