Formation Of Dissipative Structures Research Articles

Dissipative Structure Formation in Lipid/Lipopolymer Monolayers

We study the formation of dissipative microstructures in monomolecular films of surfactant mixtures, which occur near the three-phase contact line during Langmuir-Blodgett transfer onto a solid substrate. Continuous stripes parallel to the transfer direction are generated over several centimeters, indicating the phase separation of phospholipids and lipids with polymer head groups (lipopolymers). The systematic variation of transfer conditions revealed that transfer speed and subphase viscosity determine the stripe-to-stripe distance from several micrometers to submicrometers. To account for the physical mechanism of such pattern formation, we characterize the local film thickness and the membrane composition in the vicinity of the three-phase contact line using imaging ellipsometry and fluorescence microscopy. At relatively slow rates of substrate lifting, the power law exponent that we found between the interstripe distance and the transfer speed suggests that the stripe formation is due to spinodal decomposition, which can be accounted under the framework of the Cahn-Hilliard equation, whereas at relatively high rates, the distance is found to be proportional to the substrate speed, suggesting a dominant effect of the shear force on the stripe formation.

Hexagonal structures of current in a “semiconductor-gas-discharge gap” system

The results of experimental investigation of the stability boundary for a spatially homogeneous state of a discharge in the planar gap of a “semiconductor-gas-discharge” cryogenic system filled with nitrogen are considered. The semiconductor cathode was prepared from single-crystalline silicon doped with a deep-lying impurity. Quantitative data are obtained for the conditions of formation of a hexagonal dissipative structure in the current distribution for two values of the discharge gap length upon a change in the gas pressure and in the conductivity of the cathode. It is found that for a fixed gap length, the formation of the critical state can be described approximately by a universal function of the electrode conductivity and gas pressure.

Quantitative Analysis of Integrated Energy Metabolism of Muscle Cells: Experimental and Theoretical Studies

Quantitative analysis, in combination with detailed experimental studies, is the basis of Molecular System Bioenergetics (MSB) which takes into account specific interactions between cellular components, formation of metabolic dissipative structures and resulting system level properties such as metabolic compartmentation. There are several experimental and theoretical approaches used: studies in vivo kinetics of mitochondrial respiration regulation; Metabolic Control Analysis of integrated energy metabolism; mathematical modeling. Cardiac cells are characterized by high level of structural organization with very regular arrangement of mitochondria and their interaction with cytoskeleton. Heterodimeric tubulin containing beta II isoform is connected to mitochondrial outer membrane, specifically controls VDAC permeability and is coexpressed with mitochondrial creatine kinase. These proteins form with ATP Synthasome a supercomplex Mitochondrial Interactosome (MI) in which the kinetics of regulation of respiration by MtCK is significantly altered in comparison with mitochondria in vitro affinity for extramitochondrial ATP is strongly decreased due to limited permeability of VDAC but for creatine increased. Metabolic Control Analysis of reactions in MI showed that flux control coefficients are significantly increased for reactions of ADP/ATP recycling coupled with phosphocreatine production by MtCK. These experimental data are the basis of the mathematical model of compartmentalized energy transfer and show that about 90 % of energy is carried out of mitochondria by phosphocreatine due to specific structure of MI. This model explains well the metabolic aspects of Frank -Starling law of the heart. In cancerous HL −1 cells of cardiac phenotype MtCK and beta II tubulin are not expressed. Mathematical models based on the theory of homogenous intracellular medium and CK equilibrium do not explain adequately the experimental observations. In future development, application of single-molecule enzyme kinetics and theory of nonlinear biochemical reaction networks is necessary.

The processes formation of thin-film heterogeneous structures based on Ge<sub>2</sub>S<sub>3</sub> glass in dependence of the technologies conditions of their preparation

The formation of dissipative thin-film structures based on Ge 2 S 3 glass with Al, Bi, Pb, Te modificators has been described by the system of non-linear differentiated equations, where the atomic flow of the modificator, structural heterogeneity of glass matrix (the availability of vacancies, micropores) and particle diffusion was taken into consideration.

Formation of dissipative structures in liquid water

In living systems, water takes part in the dynamics of life, not only because it accounts for 99% of all biomolecules but also because it provides energy to living matter. Water has the ability to achieve an extended form of organization and provide an ensemble of different coherence domains (CDs) that are phase locked, thus maximizing their capacity to ‘look for’ energy from the environment. This ‘coherence of coherences’ of ‘biological water’ in living systems corresponds to a sort of higher organization. An efficient mechanism of energy transformation from CDs to biomolecules in living matter guarantees the transfer of biochemical energy necessary for the maintenance of life cycles. The dynamics of formation of dissipative structures in liquid water and the process of self-organization of living organisms induced by water are briefly discussed. Dissipative structures appear as a consequence of the phase locking within an ensemble of CDs. The process of charge and discharge of energy is discussed.

Electroplasticity of undoped and doped silicon

A new technology of formation of dislocation dissipative structures in undoped and doped semi-conductor crystals by the combined deformation, which makes it possible to control their elastoplastic properties, is suggested. New macroplastic properties of these crystals are found. From the obtained compression diagrams, various strain parameters are determined and surface microstructures of the obtained deformed samples are investigated. Possible physical explanations are proposed for the observed phenomenon.

Peculiarities of structural transformation in plastic materials under abrupt changes in loading conditions

In the work, a new type of mechanical tests is used in which the system under study is a mechanical system comprising three simultaneously loaded parallel elements: a test specimen and two brittle auxiliary specimens whose fracture causes an abrupt change in the strain rate of the test specimen. In the test, part of the kinetic energy released during the fracture of the auxiliary specimens is dissipated in the test specimen resulting in considerable structural changes and increased plasticity. Transmission electron microscopy analysis of the structure of deformed armco-iron and D16 alloy shows that the increase in plasticity during dynamic nonequilibrium processes is due to the formation of dissipative structures, namely localized bands. Quantitative statistical analysis of the band parameters reveals the absence of scale invariance typical of relaxation structures (cells, recrystallized grains).

An asymptotic model for the formation of large-scale dissipative structures in jet zonal flows

Large-scale vortex structures (atmospheric cyclones and anticyclones, and synoptic vortexes of the open ocean) play a significant role in the formation of weather and climate as well as in the processes of passive scalar transport [1]. An increase in the lifetime of large scale vortexes is possible at mid-latitudes due to the phenomenon of atmospheric blocking [2]. Such eddy formations were found in zonal currents, which exist in the atmospheres of large planets of the Solar System: Jupiter and Saturn. The best known is the Great Red Spot of Jupiter [3]. We can currently distinguish two approaches to the description of large-scale vortex structures in the oceans

Comments on “New Physico-Chemical Properties of Extremely Dilute Solutions. A Conductivity Study at 25 °C in Relation to Ageing”

Recently, Elia and coworkers published in this journal a paper entitled “New PhysicoChemical Properties of Extremely Dilute Solutions. A Conductivity Study at 25 °C in Relation to Ageing” [1] and claimed that from the temporal evolution of conductivity observed in extremely diluted solutions (EDS), a new physico-chemical property related to the age of the solutions may stem from modifications in the supermolecular structure of water. They suggested that the succussion process used to prepare the EDS could trigger the formation of dissipative structures in the EDS. Although in the article the authors avoid any reference to the claims made by homeopathic medicine for the action of ultramolecular dilutions in aqueous systems, the term homeopathy is one of the keywords of this paper. Moreover, V. Elia and E. Napoli coauthored a paper published in 2007 [2] in the journal Homeopathy devoted to the memory of water [3] where part of the evidence, which the authors claimed to support such a controversial phenomenon, comes also from the conductivity evolution. In that work they provide data for the conductivity evolution for the same system, covering a longer period and, consequently, yielding more complete information on the phenomenon than that reported in the paper of reference. As is well known, the “memory of water” is an expression, which appeared in the scientific literature after the paper by Benveniste [4] claiming antibody activity after ultramolecular dilutions, with contrary results published by the Nature inspection team [5]. Since then, the memory of water and its connection to homeopathy has attracted the attention of many

Sedimentation and drying dissipative patterns of colloidal crystals of poly(methyl methacrylate) spheres in a glass dish

In a series of our studies on the dissipative structure formation, this work focused on the sedimentation and drying patterns of colloidal crystals of poly(methyl methacrylate) colloidal spheres with different sizes (100, 200, 300, and 1,000 nm in diameter) in a glass dish. During the course of dryness, the brilliant iridescent colors changed. Drying frontier grew from the central area of the cell toward the outside edge. Macroscopic and microscopic drying patterns of the resulting film from dried colloidal suspensions showed outer and inner broad rings. Size of the outer rings increased with increasing sphere concentration but did not altered sphere size, while these factors affected the inner ring size. These observations do not support the pinning effect proposed by Deegan et al.

Conductometric and calorimetric studies of the serially diluted and agitated solutions

We systematically analysed the experimental data related to the specific conductivities and heats in excess of several serially diluted and agitated solutions (SDA for short). For all of the analysed samples, we found that both the excess conductivity, χE (μS cm−1), and excess heat, QmixE (J kg−1), varied with the age of the sample (up to 2 years of ageing). Furthermore, we found that after a certain period of ageing, small volume samples exhibited a much higher excess than large volume ones. The results we report in this paper are the product of a systematic study, during which we operated on known and constant volumes across the life of the samples. The incidence of volume on χE and QmixE turned out to be overwhelming when compared with that of time. The temporal evolution of the smaller samples was found significantly higher than that of the larger volume ones. A careful numerical analysis of the results uncovered an extraordinary and unexpected correlation, of exponential kind, between the excess parameters and the volume of the solution in the container. As for the temporal evolution of these systems, we found that the measured excess heats and conductivity often reach a maximum. That led us to the conclusion that the temporal evolution of the physico-chemical parameters is not caused by the slow process of equilibrium attainment; on the contrary, these systems are far from equilibrium systems, dissipative structures, whose experimental behaviour is certainly due to the variation of the super-molecular structure of the solvent, water. The agitation phase during the preparation could be the trigger for the formation of dissipative structures and the emergence of the novel behaviour. We put forth a simple rationalizing hypothesis, based on the general idea of water as an auto-organizing system that, when elicited by even small perturbations, can enter a far from equilibrium state, sustained by the dissipation of the electromagnetic energy coming from the environment. (Dissipative Structures).

Convectional, sedimentation and drying dissipative patterns of colloidal crystals of poly(methyl methacrylate) spheres on a watch glass

Direct observation of the convectional dissipative patterns at room temperature was successful on a cover glass during the course of dryness of colloidal crystals of poly(methyl methacrylate) colloidal spheres. Formation processes of the convectional patterns of spoke-like lines were observed as a function of sphere size and also sphere concentration. During dryness of the suspensions, the brilliant iridescent colors changed beautifully. Macroscopic and microscopic drying patterns of the dried film were observed. Multiple broad ring-like patterns were observed especially at low sphere concentrations. The water evaporation accompanied with the convectional flow of water and the colloidal spheres played an important role for the dissipative structure formation.

Self-organization in nonlinear dynamical systems and its relation to the materials science

This review paper presents briefly the main concepts of nonlinear dynamics and their exemplary manifestations in selected systems, including those important from the point of view of materials science. It is an extended version of the conference presentation. The conditions of instabilities leading to spontaneous formation of dissipative structures are given. Principles of nonlinear dynamics are illustrated with several examples from the homogeneous and heterogeneous and physical and chemical systems: pattern formation in the convective motion of fluids subject to various kinds of driving forces, periodic precipitation phenomena, oscillations, and pattern formation in the Belousov–Zhabotinski (BZ) reaction and the catalytic oxidation of thiocyanate ions with hydrogen peroxide, as well as bistability and tristability in the electrochemical reduction of azide complexes of nickel(II). The application of nonlinear dynamics in materials science is first exemplified by its role in polymerization reactions. Such processes can either exhibit internal couplings leading to oscillations or can be coupled with the chemical oscillatory process through, e.g., the covalent bonding of its catalyst to the polymer network. Other selected examples of the application of nonlinear dynamics in materials science, referring to electrochemical processes, were briefly reviewed. Nonlinear dynamics appears to be useful for designing new materials, including those at the nanoscale.

Natural Fluctuation of Sulfur Species in Volcanic Fumaroles

We describe and discuss the origin of short-term (hours) variations in the concentration of sulfur species (SO2, H2S, and S80) of crater fumaroles discharging at different temperatures (up to 410°C) from five volcanic systems. Sulfur species can be investigated as an independent subsystem within the whole composition characterizing the fumarolic fluids, their chemical behavior being governed by similar laws in volcanic systems. The measured data are time dependent and show regular oscillations whose amplitude is by far larger than the analytical error. The agreement between the theoretical and the measured concentrations of SO2, H2S, and S80 suggests that the formation of dissipative structures can explain the observed oscillations. Accordingly, the periodicity and the amplitude of the compositional oscillations were found to be in strong relation with the entropy excess of the non-equilibrium systems under investigation. The results of our study suggest that the amplitude and magnitude of short-term natural (self-induced) fluctuations of the sulfur species caused by the presence of the dissipative structures, and their comparison with the compositional variations of other subsystems, should be taken into serious account for geochemical monitoring purposes.

New Physico-Chemical Properties of Extremely Dilute Solutions. A Conductivity Study at 25 °C in Relation to Ageing

The conductivity of extremely dilute solutions (EDS) was measured and studied in relation to the age of the solutions. The aim was to obtain information about the influence of succussive dilutions and succussions on the conductivity and structure of water. EDS are obtained by iteration of two processes: dilution 1:100 (mass basis) and succussion. The iteration is carried out until extreme dilutions are reached. We found significant increases in electrical conductivity with respect to the untreated demineralized water used as solvent, confirming the intriguing new behavior disclosed some time ago, namely the evolution of certain physico-chemical parameters with the age of the samples. We studied variations in electrical conductivity of samples up to two years old. Conductivities showed large variations reaching a pronounced maximum and, for several samples, then returning to their initial values. The latter fact suggests that the temporal evolution of this physico-chemical parameter does not stem from the slow attainment of an equilibrium condition, characterized by a minimum of energy, since that state, when reached, should be steady. These systems could be far from thermodynamic equilibrium, producing dissipative structures. In order to stay far from equilibrium, they need to dissipate energy. For reasons that are not yet clear, when modified environmental conditions prevent the necessary dissipation of energy, these systems return to their initial conditions. In the light of this interpretation, the succussion procedure may be the trigger for the formation of dissipative structures, the number and/or size of which increase with age, up to a certain point.

Dissipative structures in left-handed material cavity optics

We study the spatiotemporal dynamics of spatially extended nonlinear cavities containing a left-handed material. Such materials, which have a negative index of refraction, have been experimentally demonstrated recently, and allow for novel electromagnetic behavior. We show that the insertion of a left-handed material in an optical resonator allows for controlling the value and the sign of the diffraction coefficient in dispersive Kerr resonators and degenerate optical parametric oscillators. We give an overview of our analytical and numerical studies on the stability and formation of dissipative structures in systems with negative diffraction.

Laser-induced collective effects in glassy semiconductor films

Photoinduced variations in the structure of glassy semiconductor films are considered from the standpoint of the theory of self-organization, including the formation of dissipative structures and their subsequent transformation under laser irradiation, which drives the system to the new state with minimum dissipated energy of the external mechanical field. Direct experimental evidence for the existence of cooperative (synergetic) self-organization processes is provided by the results of cyclic nanoindentation measurements in films of a chalcogenide glass with As2Se3 stoichiometric composition exposed to band-gap light (hv ≥ Eg)).

Kinetic aspects in the drying dissipative crack patterns of colloidal crystals

Kinetics of the dissipative structure formation in the course of drying the colloidal crystals of silica spheres (103 nm in diameter) in aqueous deionized suspension on a rinsed cover glass has been studied by the close-up video observation. The patterns of the broad ring of the hill accumulated with the spheres coexisted with the many spoke-like cracks. The characteristic convection flow of the spheres and the interactions between the spheres and substrate were important for the pattern formation. Cracks formed suddenly in the course of drying along the outside edge first, then toward the center, and stopped around the middle point between the outside edges and the frontier of suspension area. The further growth of the cracks took place at the adjacent place of the previous crack side by side and cooperatively. After the fast formation of these cooperative spoke-like cracks was completed, then all the crack lines further developed very slowly and simultaneously toward the center with the similar rate as that of the movement of the drying frontier of the suspension area toward center. Rates of the fast and slow modes of crack formation were 6.2 mm/s and 0.0098 mm/s, respectively, at the sphere concentration of 0.033 in volume fraction.

The Self-Organisation of Tetrahedrally Close-Packed Structures in Magnetic Nanocrystalline Tb-Fe and Co-Pd Films

The self-organization of an atomic structure in Tb30Fe70 and Co50Pd50 films possessing of high values of the perpendicular magnetic anisotropy (PMA) constant (K⊥ ~ 106 erg/cm3) is investigated by transmission electron microscopy. The crystallization of the films is realized in an explosive way with formation of different dissipative structures from the initial nanocrystalline state. In present work the structural model of a thin film in mezzo-scale and the correlation of a structure with magnetic properties are discussed.

Role of nonideality of diffusion processes in the formation of dissipative structures

It is shown that inhomogeneity of diffusion fluxes, which modifies Fick’s law in chemical systems, where mono-and bimolecular reactions proceed through two intermediate components, may lead to the formation of spatial structures. Their analytic description is given on the basis of an exact solution to a set of nonlinear evolution equations. The conditions of existence are derived for time-dependent dissipative structures (limiting cycle) in the presence of nonideality of diffusion processes in the systems being considered.