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Actual work devoted to the development of a novel homological approach for describing the kinetic properties of grossly nonstoichiometric oxides AB O 3- δ with perovskite structure. The approach consists in considering such oxides having different oxygen stoichiometry 3- δ as chemical homologues involved in the same oxygen exchange reaction and forming a continuous series in δ. The proposed approach is considered using the oxide with exceptional oxygen mobility Ba 0 · 5 Sr 0 · 5 Co 0 · 8 Fe 0 · 2 O 3- δ (BSCF). The kinetic properties of BSCF were studied by new method of the oxygen partial pressure relaxation. The equilibrium properties of BSCF were reported earlier and obtained by original technique of the quasi-equilibrium oxygen release. The power law dependence of the kinetic parameters on the equilibrium oxygen partial pressure is considered as the consequence of linear free energy relationship similar to the Brønsted-Evans-Polanyi relation. • Homological approach allows to describe the kinetic properties of grossly nonstoichiometric oxides. • Grossly nonstoichiometric perovskite BSCF is considered as a homologues series continuous in δ. • The power law dependence of the kinetic parameters is considered as the consequence of LFER. [ABSTRACT FROM AUTHOR]

• Pectin hydrogels were prepared by using zein nanoparticles as crosslinkers. • These gels were fluorescent and pH-responsive. • Interpolymer networks were formed primarily by hydrophobic forces. • Gels exhibited superior cytotoxicity towards HeLa cells via intracellular-antioxidative stress-apoptosis. • These gels were used for the direct release of the anticancer drug Doxorubicin inside cell nucleus. Herein, we report pH-responsive hydrogels of hierarchically self-assembled protein (zein, in the form of its nanoparticles of size 80–120 nm) and polysaccharide (pectin), where gelation occurred below pH 3 in the absence of crosslinkers, which we used for encapsulation and release of anticancer drug, Doxorubicin (DOX) in the cell nucleus. These nanoparticles, spherical in shape, in addition to helping in the formation of gel network also encapsulate the drug and pectin layer adsorbed on the surface of these nanoparticle allows for the drying, redispersion and enhanced swelling. A monovalent salt-dependent study performed in the concentration range of 1–100 mM clearly showed the associative interaction between the zein nanoparticles and pectin chains were hydrophobic in nature. FTIR results confirmed the loading of the drug inside the nanoparticles. Melting profile studies of these gels revealed that encapsulation of drug did not change the thermo-physical properties. Doxorubicin drug loaded hydrogels exhibited superior cytotoxicity towards cervical cancer cell lines by inducing intracellular-antioxidative stress-based apoptosis. Confocal microscopy revealed that the hydrogels required quite less time of 4 h to completely penetrate the cells assisted by the charge specific electrostatic interaction between the negatively charged HeLa cells and positively charged crosslinks. The data, further revealed that these pH specific hydrogels were suitable for release of the drug in cell nucleus is assisted by the acidic environment of cellular organelles, and hence have a potential in cancer therapy with minimal collateral damage to healthy cells. [ABSTRACT FROM AUTHOR]

• Non-stoichiometric oxides ABO 3-δ are considered as continuous series of homologues. • A new relaxation methodology for the study of oxygen exchange in oxides is proposed. • Oxygen exchange in La 0.6 Sr 0.4 CoO 3-δ obeys the Brønsted-Evans-Polanyi relation. The study of the oxygen exchange of mixed ionic electronic conducting oxides with the gas phase, which determines the efficiency of devices planned to be used in distributed power generation and industrial chemistry is complicated by the strong dependence of their properties on widely varying oxygen nonstoichiometry δ. A new fruitful approach, in which non-stoichiometric oxides are considered as continuous δ -homologous series proposed for solving this problem, requires the development of a new methodology for the collection and analysis of the kinetic data. La 0.6 Sr 0.4 CoO 3- δ (LSC64) δ -homologues were used as examples to demonstrate the novel methodology for studying the kinetics of oxygen exchange by oxygen partial pressure relaxation technique. It includes analysis of the kinetic data in the isostoichiometric cross-section, a non-linear model of relaxation kinetics, a detailed consideration of the mass balance in the reactor, accounting for the particle size distribution in the sample and the response time of the experimental setup. For the continuous series of LSC64 δ -homologues, the Brønsted-Evans-Polanyi relationship is established: the linear correlation of the Gibbs activation energy with the chemical potential of the oxide, as well as the compensation effect between the activation parameters of the equilibrium oxygen exchange rate. [ABSTRACT FROM AUTHOR]

[Display omitted] • A change in the exponent n may indicate a change in the RDS mechanism. • The phase transition affects the kinetics of surface oxygen exchange. • The phase transition does not affect the mechanism of bulk vacancy mobility. Oxygen partial pressure relaxation technique was used to study transient kinetics of re-equilibration in the reaction of nonstoichiometric oxide Ba 0.5 Sr 0.5 Co 0.75 Fe 0.2 Mo 0.05 O 3- δ with oxygen within a region of 3- δ stoichiometry close to the nominal oxidation state 3+ for cobalt where an isosymmetric phase transition cubic perovskite P1 – cubic perovskite P2 is observed. The relaxation data were analyzed using a macrokinetic model that explicitly takes into account the power-law dependence of the surface reaction rate on the oxygen partial pressure. A twofold decrease in the power-law exponent (n = 0.7 to n = 0.3) was found at the point of the P1-P2 phase transition, which indicates a change in the mechanism of the rate-determining step of the reaction caused by the transition. At the same time, the functional dependence of the diffusion mobility of oxygen vacancies on the equilibrium oxygen pressure does not change at the transition point, which means that the transition does not affect the mechanism of bulk vacancy mobility. [ABSTRACT FROM AUTHOR]

In this study, the stress relaxation of amorphous Fe 0.7 Nb 0.1 Ti 0.1 Zr 0.1 alloy was investigated by differential thermal analysis (DTA) to enhance the soft magnetic properties. Amorphous Fe 0.7 Nb 0.1 Zr 0.1 T 0.1 alloy was produced by mechanical alloying technique using the mixture of pure elements and without adding metalloids. It was found that the stress relaxation process follows the Johnson-Mehl-Avrami model and the mechanism was volume diffusion control with three dimensional growth of the nuclei. The relation of stress relaxation progress (α), with time was proposed as: dα dt = β dα dT = 3.04 exp − 4312 RT 1 − α − ln 1 − α 0.37 . The final achieved microstructure leads to higher saturation magnetization and lower coercivity that are favorable for soft magnetic applications. [ABSTRACT FROM AUTHOR]

Structural relaxation during isothermal annealing, quantified by enthalpy recovery of Zr 44 Ti 11 Cu 10 Ni 10 Be 25 towards its metastable equilibrium and correlation to embrittlement, quantified through fracture toughness, K Q , is studied. Enthalpy relaxation over time obeys the Kohlrausch-William-Watts (KWW) stretch exponent with β = 0.74 and τ = 11,000 s. Such β and τ are used to fit experimental K Q ( t ) with KWW, resulting in R 2 = 0.79. This finding combined with a controlled characterization of the glasses' K Q versus temperature, fictive temperature, and their combination, revealed that embrittlement in metallic glasses is predominantly controlled by structural rearrangements, whereas volume changes from thermal expansion have negligible influence. [ABSTRACT FROM AUTHOR]

• Mo-doped BSCF oxide is studied using methods of relaxation and oxygen permeability. • Common quasi-linear kinetic model of the surface reaction is suggested for the two methods. • Quantitative agreement between relaxation and permeation is shown for the surface reaction rate. The kinetic parameters of the reaction of nonstoichiometric oxide Ba 0.5 Sr 0.5 Co 0.75 Fe 0.2 Mo 0.05 O 3-δ with molecular oxygen were determined by two independent methods: the steady-state oxygen permeability of the hollow fiber membrane and the transient kinetics of re-equilibration. To analyze the results, we used mathematical models that take into account the inhomogeneity of conditions in the relaxation reactor and gas flows in the tubular membrane. For a correct comparison of the two methods, the same formulation of the surface reaction rate was used in both models, taking into account the dependence of the reaction rate constant on oxide stoichiometry. As a result, a quantitative agreement was obtained between the values of the equilibrium exchange rate R 0 , including its activation energy, and the dependence on the oxygen partial pressure. [ABSTRACT FROM AUTHOR]

• SrFe 0.98 Mo 0.02 O 3-δ perovskite is considered as homologues series continuous in oxygen stoichiometry. • Oxygen exchange rate and diffusivity are analyzed in isobaric and isostoichiometric sections. • Brønsted-Evans-Polanyi relation is shown to be the reason of pn dependencies for kinetic constants. The properties of perovskite related oxides ABO 3- δ exhibiting mixed ionic-electronic conductivity (MIEC) are strongly dependent on oxygen stoichiometry 3- δ. The complexity of the theoretical interpretation of kinetic experiments is associated with the significant dependence of the kinetic properties of MIEC oxides on δ. It is proposed to consider such grossly nonstoichiometric oxides having different oxygen stoichiometry as chemical homologues participating in the oxygen exchange reaction and forming a series continuous in δ. The continuous homologous series approach is considered using the example of SrFe 0.98 Mo 0.02 O 3- δ. The equilibrium and kinetic properties of the oxide were studied by new methods of the oxygen partial pressure relaxation (OPPR) and quasi equilibrium oxygen release (QEOR). The power law dependence ∼ pn of the kinetic parameters on the equilibrium oxygen partial pressure is considered as the consequence of linear free energy relationship similar to the Brønsted-Evans-Polanyi relation. [ABSTRACT FROM AUTHOR]

Luminescence decay functions describe the time dependence of radiation emitted by a sample after excitation. An overview of the mathematical aspects and systematics of luminescence decays is presented. In particular, super-exponential (faster-than-exponential) decays are defined and the possibility of their observation in single species physicochemical systems discussed. It is shown that this type of behavior can be both spontaneous and induced (by acting upon the system in real time). Spontaneous super-exponentiality is identified for the first time in experimental decays, these being phosphorescence decays affected by triplet–triplet absorption. [ABSTRACT FROM AUTHOR]

Abstract: Two competing and mutually exclusive mechanisms of ligand recognition – conformational selection and induced fit – have dominated our interpretation of ligand binding in biological macromolecules for almost six decades. Conformational selection posits the pre-existence of multiple conformations of the macromolecule from which the ligand selects the optimal one. Induced fit, on the other hand, postulates the existence of conformational rearrangements of the original conformation into an optimal one that are induced by binding of the ligand. In the former case, conformational transitions precede the binding event; in the latter, conformational changes follow the binding step. Kineticists have used a facile criterion to distinguish between the two mechanisms based on the dependence of the rate of relaxation to equilibrium, k obs, on the ligand concentration, [L]. A value of k obs decreasing hyperbolically with [L] has been seen as diagnostic of conformational selection, while a value of k obs increasing hyperbolically with [L] has been considered diagnostic of induced fit. However, this simple conclusion is only valid under the rather unrealistic assumption of conformational transitions being much slower than binding and dissociation events. In general, induced fit only produces values of k obs that increase with [L] but conformational selection is more versatile and is associated with values of k obs that increase with, decrease with or are independent of [L]. The richer repertoire of kinetic properties of conformational selection applies to kinetic mechanisms with single or multiple saturable relaxations and explains the behavior of nearly all experimental systems reported in the literature thus far. Conformational selection is always sufficient and often necessary to account for the relaxation kinetics of ligand binding to a biological macromolecule and is therefore an essential component of any binding mechanism. On the other hand, induced fit is never necessary and only sufficient in a few cases. Therefore, the long assumed importance and preponderance of induced fit as a mechanism of ligand binding should be reconsidered. [Copyright &y& Elsevier]

Abstract: The synthesis of two molecules, B1 and B2, based on elements of norbadione A, the natural Cs+ chelator in mushrooms, associated, in the case of B2, with an 18-crown-6 ether is reported. Thermodynamic and kinetic analyses performed in water, ethanol and ethanol/water 9/1 v/v (M1) show in M1 and ethanol that B1 and B2 form stable complexes with Na+, K+ and Cs+. Affinity constants, measured spectrophotometrically in ethanol and M1, by the use of the Specfit program, are in the 105 and 106 range for B1 and B2, respectively. The second-order rate constants are in the 106–107 M−1 s−1 range and the first-order rate constants about unity. The ratios of the second-order/first-order rate constants confirm the thermodynamic results in EtOH. The kinetic processes become much too fast to allow runs in M1. Molecular simulations in EtOH imply the existence of two isomers for each of the Cs+/B1 and Cs+/B2 complexes. With B1, the more stable one is that in which the two enolates are parallel and mimic the alkali-metal inclusion cavity already envisaged for norbadione A. With B2, two similar structures are extracted, in both of which Cs+ is included in the crown ether and capped by the enolate. The affinity of B1 for Cs+ is comparable to that of norbadione A, whereas that of B2 is higher. These results are encouraging as they introduce a new series of alkali chelators which can lead to molecules capable of complexing 137Cs+ for radioactive decontamination. [Copyright &y& Elsevier]

Abstract: The synthesis and new optical features of four azophenylcarbazoles are described. All-optical poling of the azophenylcarbazoles with different donor groups was investigated. The highest optical poling efficiency was measured for relative larger molecules (branched). Parameters describing mobility of the azophenylcarbazoles (orientational diffusion coefficient vary from 2.2 × 10−5 s−1 to 8 × 10−5 s−1) were extracted using an adopted model. Photoinduced erasure while reading the poled media turned out to be more pronounced for less developed structures (less branched donor). Different polymer materials were investigated as the host matrix for the most interesting azophenylcarbazole molecule. [Copyright &y& Elsevier]

Abstract: The kinetics of sorption of micromolecular swelling agents by polymeric media often deviates from normal Fickian behavior in various ways, which have to be understood and interpreted, with the aid of appropriate models, in terms of the underlying physics. One difficulty which arises in this respect is that salient aspects of the observed kinetic behavior can be mimicked by extraneous effects, in the form of significant deviation from a boundary condition or of imperfect macroscopic homogeneity of the polymer film (modeled in both cases as a surface resistance to penetrant transport). Such effects have, in fact, been invoked (notably by Hansen (2010) ) to question the significance of conclusions drawn from modeling approaches based on the effect of intrinsic bulk polymer properties, leading to delayed (viscous) swelling and to build-up and decay of differential swelling stresses. We present here a brief critical account (following the mainstream modeling line initiated by Crank) of typical results concerning various salient aspects of observed non-Fickian sorption kinetics and of the comparative possibility of achieving satisfactory general interpretation thereof, in terms of approaches based on the aforementioned extraneous, versus intrinsic bulk property, effects. We find that the latter approach has been successful so far, both computationally and physically, by establishing a close physically significant analogy between non-Fickian sorption, and (both linear and non-linear) viscoelastic mechanical deformation, behavior. The former approach, on the other hand, proves weak on both counts. [Copyright &y& Elsevier]

Abstract: Pressure-jump induced relaxation kinetics can be used to study both protein unfolding and refolding. These processes can be initiated by upward and downward pressure-jumps of amplitudes of a few 10 to 100 MPa, with a dead-time on the order of milliseconds. In many cases, the relaxation times can be easily determined when the pressure cell is connected to a spectroscopic detection device, such as a spectrofluorimeter. Adiabatic heating or cooling can be limited by small pressure-jump amplitudes and a special design of the sample cell. Here, we discuss the application of this method to four proteins: 33-kDa and 23-kDa proteins from photo-system II, a variant of the green fluorescent protein, and a fluorescent variant of ribonuclease A. The thermodynamically predicted equivalency of upward and downward pressure-jump induced protein relaxation kinetics for typical two-state folders was observed for the 33-kDa protein, only. In contrast, the three other proteins showed significantly different kinetics for pressure-jumps in opposite directions. These results cannot be explained by sequential reaction schemes. Instead, they are in line with a more complex free energy landscape involving multiple pathways. [Copyright &y& Elsevier]

Photo-illumination effects have been measured for [CoIII-LS(phen)(3,5-DBSQ)(3,5-DBCat)]·C6H5Cl, where LS, phen, 3,5-DBSQ and 3,5-DBCat denote low-spin, 1,10-phenanthroline, 3,5-di-tert-butyl-1,2-semiquinonate and 3,5-di-tert-butyl-1,2-catecholate, respectively. When the Co compound was illuminated at 5 K, the magnetization value, μeff increased from 1.7 to 2.7μB. The UV-Vis absorption spectra after illumination show that the absorption band at around 800 nm, characteristic of the [CoII-HS(phen)(3,5-DBSQ)2] state (HS denotes high-spin), increased and the charge transfer band from 3,5-DBCat to 3,5-DBSQ at 2500 nm was reduced. IR spectra show that the C&z.sbnd;O stretching peak at 1280 cm-1 is significantly decreased. These results confirm that a photo-induced intra-molecular electron transfer, [CoIII-LS(phen)(3,5-DBSQ)(3,5-DBCat)]·C6H5Cl↔[CoII-HS(phen)(3,5-DBSQ)2]·C6H5Cl, was induced by 532 or 830 nm light. The relaxation kinetics of valence tautomerism was studied. For T≥25 K, kVT0=0.205 s-1 and Ea=110.38 cm-1. Below 25 K, the rate constant for the valence tautomeric relaxation as T approaches the 0 K, which suggests that tunneling is the predominant mechanism for the relaxation. [Copyright &y& Elsevier]

Temperature-jump relaxation spectrometry has been used to study the unfolding properties of Ca2+-free Drosophila calmodulin from 278 to 336 K, monitored by absorption of Tyr-138. The T-jump amplitude data are well fitted throughout with a melting temperature Tm=315.7 K, ΔHom=140.5 kJ mol−1 and ΔCpo=3.28 kJ K−1 mol−1, giving ΔGo293=7.36 kJ mol−1 for the C-domain, in good agreement with other data. The relaxation rate observed (time range 1 μs–1 ms) obeys a simple two-state kinetic mechanism throughout. The activation energy for unfolding is nearly temperature-independent, in contrast to that for refolding, and hence the transition state is relatively compact, resembling the folded state, and the relaxation time, τ, shows complex temperature dependence. The domain unfolding is a two-state process occurring with τ of ∼100 μs at the Tm. At 296 K, when the C-domain is ∼6% unfolded, kunfolding≈305 s−1, krefolding≈4660 s−1 and τ≈200 μs. This closely resembles the rate and extent of a reported C-domain exchange process, inferred from NMR line-broadening at 296 K. The inherent instability of the apo-C-domain of calmodulin indicates that the unfolded form significantly contributes to the physical properties of apo-calmodulin at normal temperatures, and this instability is enhanced by low ionic strength conditions. [Copyright &y& Elsevier]

The photocolouration of 2,2-diphenyl-5,6-benzo(2H)chromene (Chr), upon irradiation of the ring-closed form (Np), and the subsequent relaxation kinetics of one merocyanine isomer into Np were studied in several solvents at different temperatures. Deactivation of the excited Np form leads via the singlet manifold predominantly to the ring-opened cis–trans (ct) isomer which converts thermally into Np. The activation energy, Ect→Np≈77 kJ mol−1, and the pre-exponential factor, A≈1012 s−1, are essentially independent of the solvent polarity. The trans–trans (tt) isomer, which is suggested to be formed photochemically in a competing step, is thermally more stable. The triplet pathway of photocolouration can be induced by energy transfer using several sensitizers with a triplet energy of >200 kJ mol−1. The thermal relaxation time after either direct or naphthalene-sensitized colouration is the same. The mechanisms of ring opening and ring closure are discussed. [Copyright &y& Elsevier]

[Display omitted] • The Crank model may give incorrect k and D in case of vigorous reaction. • Extended samples require consideration of convective and diffusion gas transfer. • Models taking into account these factors are developed in this study. In order to determine the kinetic parameters of oxygen exchange between nonstoichiometric oxides and the gas phase, the rate constant of surface exchange k and the coefficient of bulk oxygen diffusion in the oxide D , one needs to model the kinetics of relaxation occurring under mixed diffusion-reaction control. It is shown that the widely used Crank model can misestimate the k and D values as it does not take into account such factors as (i) changes in oxygen partial pressure p O 2 in the reactor caused by vigorous reaction, (ii) the non-uniform distribution of p O 2 over the elongated oxide sample. Models taking into account these factors are discussed sequentially in this work: the ideal continuous stirred-tank reactor (CSTR) model where p O 2 varies over time as reaction proceeds; the tanks-in-series (TIS) model imitating the non-uniform distribution of p O 2 over the sample under approximation of convective gas transfer; and the model of tanks-in-series with diffusion-convective gas transfer (TSD). The TIS and TSD models (the latter one being used for low gas flow rates), which take into account all of the above factors, give the most reasonable results: the scatter of the values of the kinetic constants k and D determined at different rates of gas flow in the reactor does not exceed the reasonable experimental error. An expression is proposed for estimating k TIS , which corrects the k values obtained from the Crank model. [ABSTRACT FROM AUTHOR]

Cluster Variation Method (CVM) has been widely employed to calculate alloy phase diagrams. The atomistic feature of the CVM is consistent with first-principles electronic structure calculations, and the combination of CVM with electronic structure calculation enables one to formulate a free energy from the first principles. In the conventional CVM, however, local lattice distortion cannot be introduced into a free energy since the local lattice distortion alters the lattice symmetry from one lattice point to another and entropy formula is not justified. Hence, the phase equilibrium determined by the CVM is still under an excited state. In order to circumvent such a deficiency of the conventional CVM, Kikuchi devised the Continuous Displacement Cluster Variation Method (CDCVM) which is capable of introducing local lattice distortion into the theoretical framework of the CVM by viewing an atom displaced to a quasi-lattice point as hypothetical atomic species located at the Bravais lattice point. Then, additional freedom due to the local atomic displacements is converted to configurational freedom of a multicomponent alloy on a rigid lattice. This idea of conversion of a freedom of local atomic displacements into configurational freedom is extended to other internal freedoms to study collective atomic displacements leading to displacive phase transition and magnetic transition. As an example of the former case, we investigated cubic-tetragonal transition of ZrO 2 , where two kinds of oxygen atoms, one undergoes upward shifting and the other downward shifting associated with the tetragonal transition, are distinguished as different atomic species. This way, the cubic-tetragonal transition is treated as the binary phase equilibria of the two kinds of oxygens on a cubic lattice surrounded by fcc lattice of Zr. In the latter case of magnetic transition, we calculated Curie temperature of collinear magnetic system by viewing various magnetic spin moments of up and down spins as different atomic species. Hence, Curie temperature is determined as the temperature at which long range order of a multicomponent system vanishes. For both the cases, first-principles calculations of the transition temperature are attempted by introducing electronic structure calculations into the free energy, and reasonable values are obtained. Path Probability Method (PPM) has been known as a natural extension of the CVM to a time domain. PPM is utilized to investigate transition, relaxation and steady state kinetics upon the temperature change. Hence, the CVM and PPM are coherent to perform synthetic study from initial non-equilibrium to final equilibrium states. One of the serious problems of PPM is the fact that the number of variables involved in a Path Probability Function, which is corresponding to a free energy of the CVM, becomes formidably large with higher order approximations. This is because PPM deals with transition path from one configuration to another, hence one needs to consider all atomistic paths which connect two configurations at time t and t + Δ t. For kinetics studies, three mechanisms should be distinguished; spin-flipping kinetics, direct exchange kinetics and vacancy mediated kinetics. Among these, most studies of PPM have focused on spin flipping kinetics but vacancy mediated kinetics is most commonly observed for metals and alloys. The number of variables to formulate vacancy mediated kinetics is much larger than that of spin flipping and direct exchange kinetics. The authors developed a new formalism of time transition variables, known as path variables , and this facilitates to apply PPM for various vacancy mediated kinetics phenomena. The basic idea behind the new formalism originates from the spirit of CDCVM to convert internal freedom to configurational freedom. And the numerous transition paths from one configuration to another are dealt in the framework of configurational freedom. Among various calculations of relaxation processes, two examples are introduced. One is associated with a cubic-tetragonal displacive phase transition in ZrO 2 for which equilibrium states are determined by CDCVM as described above. For this, we employed a high order approximation with spin flipping kinetics. The other is the relaxation processes associated with up- and down-quenching in a Ni 3 Al ordered phase within the tetrahedron approximation. The vacancy mechanism is fully considered in this case, and the effects of vacancy concentration on the relaxation behavior are investigated. In the present article, recent progress of CDCVM and PPM are reviewed. [ABSTRACT FROM AUTHOR]

• Stretched exponential function fits kinetics of photoinduced effects in GeSe2 • Parameters βand τ depend on properties of light and sample prehistory • Values of β and τ are linked with mechanisms of photostructural transformations Thermally evaporated chalcogenide glass thin films are known to be highly photosensitive revealing both metastable and transient photoinduced changes of optical transmission at the fundamental absorption edge region. In-situ kinetics of metastable photobleaching and transient photodarkening as well as following light-off relaxations for as-deposited GeSe 2 thin films were studied and fitted with the stretched exponential function. Dependences of kinetic parameters β and τ on film thickness, temperature, sample prehistory and wavelength of light irradiation were analyzed. The obtained results were discussed within current approaches to mechanisms of photoinduced kinetic phenomena and structural relaxation in glasses. [ABSTRACT FROM AUTHOR]

The structural relaxation, glass transition and crystallization processes of Mg 65 Cu 25 Y 10 metallic glass are studied by Differential Scanning Calorimetry (DSC) and Mechanical spectroscopy. The relaxation model derived from the mechanical measurements is compared with the kinetics of these transformations obtained from the DSC curves. The structural relaxation kinetics is found to be controlled by the glassy dynamics following an Adams–Gibbs–Vogel function. The glass transition and crystallization kinetics are controlled by the dynamics of the supercooled melt following a Vogel–Fulcher–Tammann behaviour. The results suggest that the microscopic processes responsible of structural relaxation and aging below the glass transition correspond to the same processes generating the α-relaxation peak. [ABSTRACT FROM AUTHOR]