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In order to monitor the greenhouse gases, there is a new focus on substances that can distinguish between no harmful gases rejected to the atmosphere and capture those that must be decreased. The physico-chemical parameters involved in the expression of analytical model are obtained from the adjustments of the experimental data. We observed that this model can be used to characterize the complicated process by the steric parameters. Samples of these parameters are as follows: The number of CO2 molecules captured per binding site of the adsorbent (nCO2). The density of receptor sites of the adsorbent (FM) through the adsorption energies (ΔEa) associated for the adsorption of CO2 on the molecular sieves, which are related to Ps1 parameters. The modulus of the obtained adsorption energies from fitting data ranged between 3.99 and 4.38 kJ/mol, confirming that the adsorption in this system is exothermic and it is founded on physisorption process. Furthermore, a meticulous study of the main intrinsic characteristics of the adsorbent to the temperature impact application and ensuring the compatibility between practical and theoretical statistical physics to find the pore size was carried out. [ABSTRACT FROM AUTHOR]

Thermodynamic, energetic, and stereographic parameters controlling the acetylene adsorption on (0001) exfoliated graphite were determined. The results showed that statistical physics model 2 (monolayer with two energies) has the best correlation with the experimental data. The adsorption of acetylene molecules on exfoliated graphite surface is multimolecular adsorption. The adsorption entropies and the Gibbs free enthalpies were determined for temperature ranging from 147.72 K to 161.50 K. The obtained adsorption energy distributions show the same maximum value of 5.6 kJ.mol−1. The stereographic parameters evolution with temperature is related to the two-dimensional (2D) critical temperature, and their values suggest the formation of polyacetylene. [ABSTRACT FROM AUTHOR]

• Physico-chemical parameters are involved through the grand canonical ensemble. • The internal energy of the WPT-AC/ethanol and M-AC/ethanol systems are calculated. • The enthalpy and entropy functions of the adsorption cooling cycles are derived. • The COP is calculated by means of statistical physics treatment • Discussion of the obtained COP for different two cycles was showed. Thermodynamic analysis of two different adsorption cooling cycles was presented; the first cycle is based on an isobaric adsorption process and the second one projects an isothermal adsorption instead of an isobaric adsorption. These cooling cycles are carried out by employing the grand canonical ensemble of the statistical physics formalism. This investigation is done for two different adsorbate/adsorbent pairs i.e. Ethanol/Waste Palm Trunk (WPT-AC) and Ethanol/Mangrove wood (M-AC). The corresponding adsorption isotherms have been fitted by statistical physics models to give a description of the adsorption process through interpretations of the evolution of the involved physico-chemical parameters, specific for this process. The results showed that the ethanol molecules have been mainly adsorbed with a multimolecular process and non-parallel to the adsorbent surface involving an aggregation process before molecules adsorption. Their adsorption energies are varying from 1.40 to 3.64 kJ/mol for WPT-AC and from 3.2 to 3.81 kJ/mol for the M-AC. These values reflected a physisorption process. The calculated internal energy values suggested the exothermicity and the spontaneity of the ethanol adsorption process. The investigation aims providing a methodology of calculation of the COP for an adsorption cooling cycle by using the statistical physics treatment. The entropy and the enthalpy functions are calculated and used to perform the thermodynamic evaluation and to calculate the coefficient of performance (COP). This parameter was found to be in the interval [0.12–0.69] for ethanol/WPT-AC and [0.11-0.6] for ethanol/M-AC for the first cycle and for the second cycle [0.15-0.81] and [0.15-0.74] respectively. [ABSTRACT FROM AUTHOR]

In the present paper, a double layer advanced model was used to investigate the adsorption process putatively involved in the olfactory perception of sotolone and abhexone molecules on the human olfactory receptor OR8D1. The number of adsorbed molecules or the fraction of adsorbed molecule per site, n, informed that the two odorants molecules are docked on OR8D1 binding sites with mixed parallel and nonparallel anchorages. Furthermore, the estimated molar adsorption energy (−ΔE 1 and −ΔE 2) were inferior to 40 kJ/mol for the two adsorption systems, which confirmed the physical nature and the exothermic character of the adsorption process. In addition, stereographic characterizations of the receptor sites surface were carried out through the determination of the receptor site size distribution (RSDs) via Kelvin equation, which spread out from 0.05 to 1.5 nm. The adsorption energy distributions (AEDs) via Polayni equation show an adsorption band spectrum localized between 17 kJ/mol and 22.5 kJ/mol for sotolone and abhexone molecules respectively. A molecular docking calculation was performed. The results indicate that the binding affinities are belonging to the spectrum of the energy band of the molecules sotolone and abhexone, with values 19.66 kJ/mol and 19.24 kJ/mol. [Display omitted] • Description of olfactory perception of sotolone and abhexone molecules on OR8D1 • Statistical physics and molecular docking studies have been applied. • The adsorption energy and the receptor site size distributions are showed. • The best docked positions and the type of interactions are determined. [ABSTRACT FROM AUTHOR]

The statistical physics approach has been well studied by our research team for liquid and gaseous adsorption systems. This treatment is based on the grand canonical partition function to give new interpretations of the adsorption process at molecular level for chemical senses: olfaction and taste. This work represents a contribution to understand the olfaction mechanism of four of enantiomeric terpenes by applying a statistical physics treatment that allows giving a physico-chemical meaning to parameters involved in the analytical model. It is possible to estimate the number of adsorbed molecules per site, the anchorage number, the receptor density, the concentration at half saturation and the molar adsorption energy. Through this selection of the best fitting model and through fitted values of these parameters, we showed that the adsorption of carvone and limonene enantiomers is not a multilayer process but a monolayer monosite process (monolayer adsorption model with identical and independent sites (n ≠ 1)). The physico-chemical model parameters can be used for the energetic characterization of the interactions between the carvone and the limonene enantiomers and the human olfactory receptor OR1A1 and the determination of an olfactory band of order of 14 kJ/mol, 7 kJ/mol, 9 kJ/mol, 8 kJ/mol for (R)-(−)-carvone, (S)-(+)-carvone, (R)-(+)-limonene and (S)-(−)-limonene, respectively, through the determination of the adsorption energy values and the adsorption energy distributions (AEDs). Thanks to the grand canonical formalism in statistical physics, the negative values of the Gibbs free enthalpy indicate that the adsorption process of the four enantiomeric terpenes onto the human olfactory receptor OR1A1 was spontaneous. The exothermic adsorption mechanism involved in the olfactory perception was explained via the negative values of the internal energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three compounds of Sr-La-phosphosilicates apatites were synthesized. • Mechanochemical synthesis and solid-state reaction techniques were applied. • The compounds were composed of a single pure apatitic phase. • Solid 31P and 29Si NMR data displayed a single crystallographic site for phosphor. • Statistical physics suggested that the adsorption of methylene blue was physical with energies lower than 30 kJ/mol. In this work, three compounds of Sr-La-phosphosilicates apatites, with the chemical formula Sr 10 -xZn 0.66 Ndx(PO 4) 6-x (SiO 4) x O (where x = 0, 2 and 4), were synthesized using mechanochemical synthesis and solid-state reaction techniques. The prepared compounds were characterized using powder X-ray diffraction (XRD), Infrared spectroscopy (FT-IR), 31P and 29Si MAS NMR, Scanning Electron Microscopy (SEM), Thermogravimetric analysis (TGA), and Brunauer-Emmett-Teller (BET). The compounds were composed of a single pure apatitic phase crystallizing in a hexagonal system with the space group P6 3 /m. The calcined compounds showed an increase of the crystallinity degree and the size of the crystals. Solid 31P and 29Si NMR data displayed a single crystallographic site for phosphor element. The single resonance peak at −76.21 ppm, in the 29Si specruim, confirmed to Q0 type silicon specie. The compounds were further applied for the adsorption of Methylene Blue from water. The highest adsorption capacity was reached using Milled-4 sample (515 mg/g). It was 363 mg/g for the calcined-4 one. The statistical physics (AMSP) investigation suggested that the adsorption of methylene blue was physical with energies lower than 30 kJ/mol. [ABSTRACT FROM AUTHOR]

This work is a contribution to understand the taste mechanism of caffeine molecule using a modeling of a putative adsorption process by model expressions established by a statistical physics treatment. A physicochemical and a gustative parts are the main constituents of this work. We start with a physicochemical investigation of the adsorption process of caffeine molecule, as adsorbate in liquid phase, onto β-cyclodextrin as adsorbent. Experimental adsorption isotherm curves of caffeine onto β-cyclodextrin coated onto Quartz crystal are carried out at three different temperatures. The Hill model expression with three parameters n, N M and C 1/2 , established by statistical physics formalism investigated in part I, is the best fitting model of the experimental data. Thermodynamic potential functions that govern the adsorption process, such as entropy, internal energy and Gibbs free enthalpy are investigated. PSD and AED are derived by a steric and energetic derivatives of the Hill model. In part II the same method of fitting is applied to the taste electrophysiological dose-response curve by a caffeine putative adsorption on gustative nerve in caterpillar. All the physicochemical parameters introduced in the fitting Hill model expression, serve first, to analyze the taste mechanism of the bitter caffeine taste. Secondly, all these stereographic and energetic parameters will be considered henceforward for an objective characterization of caffeine molecule taste in both its two aspects, intensive and qualitative aspects of caffeine taste. • Modeling of adsorption process isotherms of caffeine on β-cyclodextrin. • Modeling of electrophysiological dose-taste response curve of caffeine in caterpillar by a putative adsorption process. • Comparison of physicochemical proprieties of caffeine deduced from its adsorption on β-cyclodextrin receptor sites and of caterpillar nerve receptor sites. • Quantitative characterization of caffeine taste by means of fitting model parameters of its taste dose-response curve. [ABSTRACT FROM AUTHOR]

• The single and binary adsorption of amoxicillin and doripenem on HKUST-1 was evaluated. • Interpretation of the single and binary adsorption mechanisms at different temperatures. • Description the competitive effect via statistical physics model. • Simulation of the adsorption process via DFT. The adsorption of amoxicillin (AMX) and doripenem (DRPNM) on copper benzene-1,3,5-tricarboxylate (HKUST-1) in single and binary systems is analyzed in this paper. The experimental results showed that the adsorption capacities of this MOF for the removal of these pharmaceuticals reduced from single to binary solutions. A monolayer adsorption model and its extended competitive version were successfully applied to analyze the adsorption data. The modeling results showed that the reduction of AMX and DRPNM adsorption capacities was explained by a competitive effect of these adsorbates generating an antagonistic behavior for both molecules where the same adsorption site was involved during their removal. The statistical physics model was also utilized to estimate the AMX and DRPNM adsorption orientation on the HKUST-1 surface. Adsorption energies were calculated confirming an exothermic removal process for both molecules and DFT simulations allowed to determine the role of hydrogen bonding in the adsorption mechanism. It was concluded that the interactions for the adsorption of DRPNM on this MOF were higher than those for AMX removal. Particularly, the oxygens linked to the cupper ions on MOFs structure played a crucial role during the adsorption mechanisms of these organic compounds. Overall, this paper presents a combination between experiment results and two different theoretical approaches to provide a new explanation of the mechanism of adsorption of two relevant antibiotics on HKUST-1 MOF. [ABSTRACT FROM AUTHOR]

• Four response curves were fitted by an advanced monolayer model of ideal gas. • Physico-chemical interpretations of the studied olfactory systems were determined. • Quantitative characterizations of the olfactory systems were investigated. • Four olfactory bands of the four vanilla-like odorants were determined. An advanced monolayer adsorption model of an ideal gas was successfully employed to investigate the adsorption of vanillin, vanillin methyl ether, vanillin ethyl ether, and vanillin acetate odorants on mouse eugenol olfactory receptor mOR-EG. In order to understand the adsorption process putatively introduced in olfactory perception, model parameters were analyzed. Hence, fitting results showed that the studied vanilla odorants were linked in mOR-EG binding pockets with a non-parallel orientation, and their adsorption was a multi-molecular process (n > 1). The adsorption energy values that ranged from 14.021 to 19.193 kJ/mol suggested that the four vanilla odorants were physisorbed on mOR-EG (ΔEa < 40 kJ/mol) and the adsorption mechanism may be considered as an exothermic mechanism (ΔEa > 0). The estimated parameters may also be utilized for the quantitative characterization of the interactions of the studied odorants with mOR-EG to determine the corresponding olfactory bands ranging from 8 to 24.5 kJ/mol. [ABSTRACT FROM AUTHOR]

In the present paper, a putative adsorption process of two odorants thiols (3-mercapto-2-methylbutan-1-ol and 3-mercapto-2-methylpentan-1-ol) on the human olfactory receptor OR2M3 has been investigated via advanced models developed by a grand canonical formalism of statistical physics. For the two olfactory systems, a monolayer model with two types of energy (ML2E) has been selected to correlate with the experimental data. The physicochemical analysis of the statistical physics modeling results showed that the adsorption system of the two odorants was multimolecular. Furthermore, the molar adsorption energies were inferior to 22.7 kJ/mol, which confirmed the physisorption process of the adsorption of the two odorant thiols on OR2M3. In addition, quantitative characterizations of both odorants were determined via the olfactory receptor pore size distribution (RPSD) and the adsorption energy distribution (AED), which were spread out from 0.25 to 1.25 nm and from 5 to 35 kJ/mol, respectively. For thermodynamic characterization of the olfactory process, the adsorption entropy indicated the disorder of the adsorption systems of 3-mercapto-2-methylbutan-1-ol and 3-mercapto-2-methylpentan-1-ol on the human olfactory receptor OR2M3. Besides, the used model showed that the presence of copper ions increases the efficacy (olfactory response at saturation) of 3-mercapt-2-methylpentan-1-ol odorant activating OR2M3. The docking molecular simulation indicated that the 3-mercapto-2-methylpentan-1-ol molecule presented more binding affinities (17.15 kJ/mol) with olfactory receptor OR2M3 than 3-mercapto-2-methylbutan-1-ol (14.64 kJ/mol). On the other hand, the two estimated binding affinities of the two odorants belonged to the adsorption energies spectrum (AED) to confirm the physisorption nature of the olfactory adsorption process. • Statistical physics was used to study the dose-olfactory response curve of odorous thiols. • Thermodynamic investigation has been carried out with statistical physics models. • The olfactory receptor pore size distributions (RPSD) and the adsorption energy distributions (AED) are determined. • Effect of metal transition ion Cu2+ on 3-mercapto-2-methylpentan-1-ol complex is studied. • Molecular docking simulation have been applied to investigate the ligand/receptor complex interactions. [ABSTRACT FROM AUTHOR]

In the present paper, statistical physics formalism was used to understand the olfactory perception via the investigation of dose-olfactory response curves of a putative adsorption process of nine non key food odorants (non-KFOs) on the broadly tuned human olfactory receptor OR2W1, in order to quantitative characterize the interactions between the nine studied non-KFOs, i. e., furfuryl sulfide, furfuryl disulfide, benzyl methyl disulfide, furfuryl methyl disulfide, benzyl methyl sulfide, 1-phenylethanethiol, benzyl mercaptan, furfuryl methyl sulfide and 3-phenylpropanol molecules and OR2W1 binding sites at a molecular level. Two advanced adsorption models have been proposed: the advanced monolayer monoenergy model (monolayer model with identical and independent olfactory receptor binding sites) (Model 1) and the advanced monolayer model with two independent types of olfactory receptor binding sites (Model 2). It was concluded that the monolayer monoenergy model was selected as the most adequate model to fit the experimental dose-olfactory response curves tabulated in literature. Actually, the numerical values of the three fitted physico-chemical parameters (R M1 , n and C 1) were obtained by a non-linear regression. Indeed, modeling results suggested that the number of docked non-KFOs per OR2W1 binding site n values (1.24 < n < 1.94) was always superior to 1, which indicated the non-parallel orientation of the studied odorants on the olfactory receptor and the multi-molecular adsorption mechanism. The estimated molar adsorption energy ΔE a values (ranged from 6.07 to 12.16 kJ/mol) for the nine olfactory systems confirmed the physical the exothermic characters of the adsorption process since ΔE a values were lower than 40 kJ/mol and positive. Furthermore, these estimated parameters were applied to characterize stereographically and energetically the interaction between the nine non-KFOs and OR2W1 through the determination of the human receptor binding site size distributions (RSDs) and the adsorption energy distributions (AEDs), which were spread out from 0.25 to 6.50 nm and from 0 to 22.50 kJ/mol, respectively. The docking computation between these nine non-KFOs and OR2W1 proved that the estimated binding affinities were belonged to the adsorption energies spectrum in general and the specific adsorption energy band or the molecular vibration modes limited spectrum (between 2.50 kJ/mol and 17 kJ/mol) (approximate olfactory band). • Nine non-KFOs dose-response curves were fitted by a monolayer statistical physics model. • Stereographic and energetic interpretations were derived from olfactory response curves. • Stereographic and energetic characterizations were determined via the estimation of nine RSDs and AEDs. [ABSTRACT FROM AUTHOR]

• Modeling of the Resorcinol adsorption isotherms on activated carbon by the double layer model with two energies. • Steric and energetic interpretations of Resorcinol adsorption process were provided. • AED and PSD were computed with our statistical physics model. The adsorption isotherms of Resorcinol (RES) on activated carbon from avocado seeds (ASAC) at different temperatures were interpreted using a double layer model with two energies. The formulation of this model was established by a statistical physics treatment. Steric and energetic parameters related to the adsorption process have been considered. In addition, PSD and AED are determined from the expression of the adsorbed quantity Q. According to our detailed study the double layer model with two energies is the best fitting model. The estimated values of the adsorption energies indicated that the Resorcinol is physiosorbed. The theoretical expressions provide a good understanding and interpretation of the adsorption isotherms at the microscopic level. ASAC is macroporous since the size of the activated pores is between 60 nm and 80 nm. Moreover, we underline the fact that an increase in temperature implies a considerable increase in AED and a slight translation towards the lowest energies. Our results indicated that for working at high temperature represents the best efficiency of wastewater depollution. This work contributed to new theoretical insights on the resorcinol adsorption. [ABSTRACT FROM AUTHOR]

New statistical mechanics approach for pore size distribution applied in wide the relative pressure range is proposed. The new proposed model was applied to nitrogen adsorption-desorption isotherms at 77 K onto five functionalized polystyrene latices. Results showed that the proposed model can reproduce all results found by traditional methods such as NLDFT, BJH and VBS where some of them can be applied only for a specific range of pore size. A segmentation procedure is adopted and it is shown that the corresponding algorithm can be successfully applied for determining pore size distributions over a wide range of pore size. When this method is applied an isotherms Type II and III (materials with larger mesopores and/or macropores) gives additional information that is not obtained with the other methods. The obtained results showed that the copolymerization plays an important role in the porosity and the specific surface area, whereas, the high polydispersity index, PDI, can reduce the porosity. The samples studied within the present work present small and large mesopores and even macropores as it is suggested by the new proposed model, and part of this porosity could be related to the interparticle and also to the intraparticle porosity. [ABSTRACT FROM AUTHOR]

This work represents a contribution to understanding the taste or gustatory mechanism of sucrose by using a proposed model expression established by a statistical physics treatment. Gustative and physicochemical parts are used as constituents in this work. We start with a modeling of experimental adsorption isotherms of sucrose molecules onto β-cyclodextrin followed by a similar modeling of sweet taste dose-response curves of sucrose by a putative adsorption process of sucrose molecules onto nerve receptor sites. Numerical values of the three involved parameters in the expression of the best fitting model are derived by adjustment, namely the number of adsorbed molecules per site n, the adsorption capacity Q M and the energetic coefficient C 1/2. Steric and energetic interpretations are given. The internal energy, adsorption entropy, and Gibbs free enthalpy are studied. The pore size distribution (PSD) and the adsorption energy distribution (AED) of β-cyclodextrin and of host cavities in gerbil nerve. In the second part the same method of fitting is applied to the biological sweet taste dose-response curves of the same molecule (sucrose) on taste receptor cells in gerbil nerve (electro-physiological) and in human (psychophysical). All this information and physicochemical parameters are introduced in the model expression to fit the putative adsorption of sucrose molecule. And, all these stereographic and energetic parameters will be considered henceforward to objectively characterize the sucrose molecule sweet taste. Furthermore, all these parameters determined in the two parts are compared with other sucrose adsorption results established by other authors. • Modeling of adsorption process isotherms of sucrose on β-cyclodextrin • A putative adsorption used for of fit dose-taste response of sucrose on gerbil • Quantitative characterization of sucrose taste with fitting parameters values • Comparison of parameters of sucrose from β-CD adsorption and gerbil nerve response [ABSTRACT FROM AUTHOR]

• Lignocellulosic biomasses were used to study the adsorption of a textile dye. • Pecan nutshell, para chestnut husk, araucaria bark and palm cactus were used as adsorbents. • Monolayer and double layer models allowed the interpretation of dye adsorption mechanism. Biomasses from pecan nutshell (PN), para chestnut husk (PCH), araucaria bark (AB) and palm cactus (PC) were employed to study the adsorption mechanism of a relevant textile pollutant namely crystal violet (CV). Experimental isotherm data performed at the best condition of pH showed that the temperature had no effect on the adsorption of CV on PN and PCH, while the CV dye removal with AB and PC was significant affected by this operating parameter. Monolayer and double layer adsorption models were applied to analyze and explain, based on statistical physics, the removal mechanism of CV using these adsorbents. The application of these statistical physics models allowed to deduce theoretically that the active sites of PN and PCH practically attracted the same number (i.e., 1.12 < n ms < 1.20) of CV dye molecules at all adsorption temperatures; while a variable number of CV dye molecules (0. 81 < n ms < 2.10) could be bonded by the adsorption sites of adsorbents AB and PC. It was also confirmed that the temperature has a negligible effect on the adsorbed quantity of the systems CV-PN and CV-PCH, but it significantly impacted the systems CV-AB and CV-PC generating different magnitudes of the adsorption energies. The adsorption energy was calculated and the adsorption mechanism was analyzed thus suggesting that hydrogen bindings and van der Waals interactions could be possible for the adsorption of this dye on tested biomasses at optimum pH. [ABSTRACT FROM AUTHOR]

A grafted clay with 3-aminopropyl-triethoxysilane was employed to study the adsorption of two textile dyes acid red 1 (AR-1) and acid green 25 (AG-25). Adsorption isotherms were analyzed at six temperatures (298–323 K) to characterize the behavior of the adsorption capacity of AR-1 and AG-25. A generalized adsorption model based on statistical physics was selected to understand the removal of these textile dyes from aqueous solution. Modeling results showed that both dyes were adsorbed with a parallel position on clay surface at all tested temperatures and, consequently, this adsorption was a multi-docking (multi-interactions) process. Steric interpretations were discussed to explain the dyes adsorption mechanism via the investigation of the number of linked dyes per main active site of the grafted clay, the estimated number of dyes formed layers, the density of receptor sites and the adsorption capacity. This generalized model provided two adsorption energies characterizing the possible interactions between dye-grafted clay and dye-dye, which ranged from 27.149 to 32.991 and from 20.139 to 24.968 kJ/mol, respectively. These energies were estimated and interpreted to understand the thermodynamic behavior of the adsorption mechanism. Results showed that only physical interactions were possible for these adsorption systems. • Investigation of dyes adsorption via multilayer statistical physics model • Steric interpretation of dye adsorption on clay was performed. • Characterization of the adsorption mechanism via energetic parameters [ABSTRACT FROM AUTHOR]