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Various researches are employed to analyze the role of various indifferent electrolytes on the concentration polarization, potential distributions and the monolayer charge of the process of Langmuir monolayer deposition onto a substrate surface. The results show that the indifference electrolytes lead to an increase in the deposition rate, which further increases the monolayer ionization and charge that is not normally observed otherwise.

Instability due to surfactant redistribution in a liquid membrane system consisting of two solutions separated by a layer of immiscible liquid was theoretically studied. A mechanism of oscillation, which develops at the membrane/acceptor phase interface, was proposed on the basis of direct numerical simulation of the system evolution.

The thermodynamic characteristics of the cluster formation for fatty acids with the general formula of nondissociated n-carboxylic acids C(sub n)H(sub 2n+1)COOH with n = 5-15 are studied. The contributions of the CH2 groups to the thermodynamic characteristics of alcohols and acids are the same and the differences in the formation of clusters by these substances are attributed to the differences in the structure and interactions of relevant functional groups.

A study for addressing the electric field and ionic concentration distributions developing around the three-phase contact line during the Langmuir-Blodgett deposition of charged monolayers is conducted. The results reveal that, for sufficiently high deposition rates, the subphase composition substantially changes in the immediate locality of the three-phase contact line.

The study calculated the framework of PM3 molecular orbital approximation the thermodynamic function characteristics of the formation and geometrical structure of monomers, dimers, trimers, and tetramers of fluoroalkanols. It concluded that fluoroalkanol monomers posses a helical structure with an average backbone torsion angle equal to 162 degree, which implies optical activity of these molecules and the existence of two types of dimers, dimers with equal and opposite directions of helixes winding.

A study was conducted on the effect of high NaCl concentrations in the aqueous subphase on the structure and phase properties of selected n-hydroxystearic acid monolayers. The main characteristic features of 2-, 9-, 11-, and 12- hydroxystearic acid monolayers spread on 1 M NaCl aqueous pH 3 subphase were determined by studying the phase behavior, morphological texture, and lattice structure.

The mechanism of the meniscus oscillations and the stripes formation within the deposited fatty acid monolayer is theoretically analyzed on the basis of a supposition of concentration polarization within the solution during the deposition process. The results reveal that the proposed mechanism corresponds to the observed meniscus behavior during oscillations and agrees with numerous experimental data on adhesion work, contact angles, and maximum monolayer deposition rate.

The chiral discrimination energies in domains composed of chiral amphiphilic monolayers are theoretically studied. However, systematic coarse-graining of model systems shows that the consistent use of a set of parameters can correctly predict the chiral preference. The model calculation suggests that, with a gradual loss of chirality of the model molecule, the chiral interaction is diminished.

An effective pair potential (EPP) theory was used to correlate the molecular chiral structure of a phospholipid dipalmitoylphosphatidylcholine (DPPC) and the handedness of the mesoscopic domain composed of DPPC. The distribution of the headgroup orientation in the aqueous subphase does not destroy the chirality of the domain shape.

The dynamics of a mixed monolayer consisting of a soluble tailored amphiphile N-decyl-gamma-hydroxybutyric acid amide and its insoluble condensing homologue N-tetradecyl-gamma-hydroxybutyric acid amide are experimentally and theoretically studied. The result reveals that the theoretical predictions are in satisfactory agreement with the experiments.

The solubility of the surfactant in water is mainly responsible for the oscillation amplitude and the maximum surface velocity. Oscillation amplitude and surface velocity increases, with increasing solubility of the surfactant,

Mixed monolayers of 1-monostearoyl-rac-glycerol (StGl) and 1-(12-hydroxy)monostearoyl-rac-glycerol (12OH-StGl) are analyzed by means of pressure-area (pi-A) isotherms, Brewster angle microscopy (BAM) and grazing incidence X-ray diffraction (GIXD). Negative values of excess free energy of mixing are found for the monolayers with low 12OH-StGl content and this indicates stronger interactions between the unlike molecules of the two species in the monolayer and complete miscibility of the two components.

The thermodynamic and textural properties of dipalmitoyl-phosphatidylglycerol monolayers are described.

A theoretical and experimental study was conducted that related to research on the use of insoluble-soluble-amphiphile-consisting mixed monolayers to investigate the penetration of insoluble monolayers by a soluble surfactant or protein. The study investigated a simple system consisting of the mixed monolayer of an insoluble, C=20, and soluble, C=12 homologue of dimethylphosphide oxide. It was shown that both the effect of a soluble component on the attributes of the aggregated equilibrium and the effect of the surface pressure increase of the mixed monolayer can be analyzed.

Research was conducted to examine a new equation of state valid for Langmuir monolayers. The theoretical model takes into account the 2D aggregation of monolayer material and the compliance with the important case that the molar area of molecules within an aggregate can differ from that characteristic for free monomers. The Pi-A isotherms for Langmuir monolayers of different amphiphiles are in good agreement with the proposed model for physically reliable values of model parameters.

Research was conducted to examine the transition state between monolayers of palmityl acetate and the transition between the tilted monolayer phases using grazing-incidence X-ray diffraction. The monolayers were observed to undergo a transition from a phase with alkyl chains tilted toward nearest neighbors to a phase with chains tilted toward next-nearest neighbors upon monolayer compression. The crossover from one texture to the other is found to be separate from the transition between the tilted phases.

Experiments were conducted to analyze and compare condensed-phase structures of adsorbed Gibbs monolayers and spread Langmuir monolayers in acid amide compounds. The parameters of comparison included the thermodynamic behavior, configuration and crystal structures of the monomolecular layers. The Brewster angle microscopy was utilized to examine the monolayers' condensed-phase domains. The findings revealed that defects in the Gibbs monolayers were less in comparison with the Langmuir monolayers.

Grazing incidence X-ray diffraction and Brewster angle microscopic studies were performed to determine the Langmuir thin layers of several fatty acids and their methy and ethyl esters. The fatty acid samples examined were myristic acid, palmitic acid, methyl palmitate and ethyl palmitate. The influence of the headgroup structure on the texture and composition of the condensed phases was also investigated. Differences in the monolayers of these substances were attributed to their degree and direction of dispersion.

The monolayer features of two very similar amphiphiles, N-tridecyl-[beta]-hydroxypropionic acid amide (THPA) and N-([beta]-hydroxyethyl) tridecanoic acid amide (HETA) and their 1:1 mixture are analyzed. The thermodynamic analysis has provided results on the specific phase properties of the mixed HETA/THPA monolayers.

The generalization of the equation of state for the monolayer with a fluid/condensed phase transition derived in the framework of a quasichemical approach is reported. The calculated results from equations provide insight into entropy nonideality of mixing of the monomers and clusters of amphiphilic molecules.

A study results which give additional information on the recognition kinetics for the dissolved non-surface-active substrates and the stability of the formed interfacial supramolecular complexes performed on 2[C.sub.11][H.sub.23]-melamine monolayers and barbituric acid as the pyrimidine derivative dissolved in the aqueous subphase is presented.

The effect of a very small change in the chemical structure of an acid amide amphiphile on the characteristic features of the Langmuir monolayers, which is not based on chirality, is investigated. The synthesis of amphiphiles N-tridecyl-beta-hydroxypropionic acid amide (THPA) and N-(beta-hydroxyethyl)tridecanoic acid amide (HETA) has allowed the comparison of the monolayer characteristics of two very similar amphiphiles, the chemical structure of which is only changed by exchanging the position of the two substituents at the acid amide group.

The equation of state for the monolayer comprised of the molecules of different sizes is modified to describe the fluid state of the molecules monolayer. The values of molecular areas of amphiphilic molecules estimated from the fitting of experimental data to the proposed equation are found to be quiet similar to those measured in independent grazing incidence X-ray diffraction experiments.

A new derivation for an equation of fluid state of Langmuir monolayers was given by Anatoly I. Rusanov, which claimed that, the basic differential equation of state and all other equations derived on its basis are incorrect. Rusanov reveals that excluded area is not the defining factor but in his equations he has taken the factor of excluded area equal to unity as an approximation, which shows that his comments are erratic.

The result of theoretical and experimental studies of spontaneous nonlinear oscillations produced at the liquid/liquid interface by surfactant transfer from a point source situated in one of the bulk phases are presented. It is concluded that auto-oscillations at the air/liquid and liquid/liquid interfaces are governed by very similar mechanism but their characteristics are strongly dependent on the properties of the two contacting media, in particular, on the surfactant partition coefficient.

The main characteristics of Langmuir monolayers are radically changed by molecular recognition of hydrogen bond nonsurface-active species. Grazing incidence X-ray diffraction measurements results reveal that molecular recognition of pyrimidine derivatives gives rise only to quantitative changes in two-dimensional lattice structure.

The effect of buoyancy on surface tension auto-oscillations is examined. The buoyancy force results in a considerable decline of the induction period and the period of oscillations when the surface solution density is smaller than the density of the pure liquid.

A drastic change of the characteristic features (Pi-A isotherms, morphology of the condensed phase domains) of the 2C11H23-melamine monolayers by molecular recognition of the pyrimidine derivatives uracil and thymine, large affected by the reaction kinetics of the recognition process is studied. The experimental data reveals that the main characteristics of the interfacial system are largely affected by the reaction kinetics of the recognition process.

The thermodynamic and structural properties of the Langmuir monolayers of a homologous series of a selected amphiphilic melamine-type are presented. The findings suggest that good candidates for the formation of supermolecular structures are monolayers of amphiphilic melamine derivatives.

The change in the thermodynamic, phase and structural properties is studied as a result of molecular recognition of dissolved thymine by medium chain dialkyl melamine-type monolayers is studied. It is demonstrated that the molecular recognition of the nonsurface-active thymine dissolved in aqueous subphase changes drastically the characteristic features of the 2C11H23-melamine monolayer.

The role of electrostatic interaction in the domain morphology of amide, ether, ester, and amine monoglycerol monolayers with systematic variation in the molecular structure of the headgroup region is investigated. The results suggest that the characteristic feature of the condensed monolayer phase is very different for these monoglycerols.

Experimental studies of the dynamics and equilibrium of the penetration of the soluble cationic surfactant cetyltrimethylammonium bromide (CTAB) into arachidic acid monolayers are reported. A new theoretical model is proposed involving the enthalpic nonideality of the mixed monolayer.

Interesting crossover from heterochiral preference to homochiral preference of the 1-O-hexadecyl glycerol amphiphile in Langmuir monolayers is discussed. The calculation of the magnitude of discrimination depends on the representation of the molecular structure used in the theoretical calculation and is consistent with the previous calculations.

The thermodynamic behavior and the structure features of hydroxyctadecanoic acid monolayers, which are largely affected by the position of the hydroxyl group in the alkyl chain are discussed. In combination with the GIXD experimental data it is possible to draw conclusions on the orientation of the molecules in the different monolayer states and their changes at the main phase transition.

A numerical study of the processes that occur in a small cylindrical vessel with rigid walls, by the dissolution of a surfactant droplet placed n the capillary up under the free water interface is presented. The numerical and experimental results are compared and discussed.

The equation of state for Langmuir monolayers was generalized for the case that one, two or more phase transitions in the monolayers take place, provided that the two-dimensional compressibility undergoes a jump at the phase transition. Within any condensed phase of the monolayer this compressibility is proportional to the surface pressure.

A comparative analysis of a theoretical model, which describes the displacement of the two-dimensional phase equilibrium in monolayers at the air/water interface, is performed. The thermodynamic characteristics for the first-order phase transition are calculated on the basis of various theoretical models.

Reasonable values of the thermodynamic characteristics for the cluster formation of odd alcohols at the air/water interface are obtained by the quantum chemical PM3 approximation. The calculated values of enthalpy deltaH(sub m)(super cl), entropy deltaS(sub m)(super cl) and Gibbs energy deltaG(sub m)(super cl) for the formation of clusters of a given structure depend linearly on the number of CH2 groups in the odd alcohol molecule.

The influence of electrical interactions on the composition of Langmuir films is studied. The overlapping electric double layers in the region close to the three-phase contact line are described, and the instability mechanisms during the Langmuir wetting process are discussed.

The coadsorption of sodium dodecyl sulfate (SDS) and dedocanol mixtures from aqueous solution is examined and compared with the adsorption of the single components. The adsorbed monolayers of the single components SDS and dedocanol show differences in the 2-dimensional phase behavior.

The surface pressure adsorption kinetics pie(t) and Brewster angle microscopy (BAM) studies are combined for characterizing the two-dimensional phase transition. The standard thermodynamic characteristics calculated are used to compare the adsorption of dodecanol from the aqueous solution and the dodecanol aggregation in the adsorbed monolayer.

Monolayer mixtures of arachidic (eicosanoica) acid with cholesterol are investigated on a subphase of pH 12.0 at 25 degree Celsius using grazing incidence X-ray diffraction (GID) and Brewater angle (BAM). It was concluded that the isolation of the domains embedded in a condensed matrix allows the observation of the recovery of the inner domain structure with variation of the surface pressure.