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Dr. Andrei RotaruINFLPR—National Institute for LaserPlasma and Radiation Physics, Laser DepartmentMagurele (Ilfov), Bucharest, Romaniaandrei.rotaru@inflpr.roThis compilation is based on the peer-reviewed and selected papers presented at CEEC-TAC2Prof. Daumantas MatulisDepartment of Biothermodynamics and DrugDesign, Institute of BiotechnologyVilnius University, Vilnius, Lithuaniamatulis@ibt.lt

Solid fuels represent one of the most used sources of energy in many countries. In terms of ranking for the coal deposits, Romania occupies the 26th place in the world, and the 11th place in Europe, with reserves of 22 million tones of bituminous coal (BC) and 472 million tones of lignite. The National Bituminous Coal Company extracts the most significant amount of BC from the Jiu Valley area, a Subcharpatian basin in the Parâng Mountains. In the present article, the BC extracted from the Livezeni depth mine next to Petrosani city is investigated from the microstructural, thermal, and kinetic point of view, in comparison with a sample from Ural Mountains in Russia. Scanning electron microscopy, FTIR spectroscopy, and thermal analysis (TG/DSC/DTA in air and inert atmosphere) measurements were performed. The KAS isoconversional kinetic method was applied for the in-depth understanding of thermal decompositions and burning processes that occur. Even if the thermal behavior of the two samples is generally similar, the non-isothermal kinetic study revealed important differences in the pathways of the oxidative decomposition of volatiles and formation of coke. Also, the kinetics of coke burning depends only on the amount of fix carbon, regardless of the provenience of BC.

Zinc(II) coordination compounds may provide a better source for ZnO thin films obtaining, since ZnO was found as the final product of their thermal decomposition. Thin films of zinc benzoate have been obtained on silicon substrates by matrix assisted pulsed laser evaporation (MAPLE) technique, using a Nd:YAG laser working at 266 nm. A comparative study of 1% zinc benzoate frozen solution in methanol at different fulences was carried out for 20,000 laser pulses; for the best deposition fluence a double deposition time was employed. Comparative thermal analysis and non-isothermal kinetic investigation of Zn(C6H5COO)2·2H2O dehydration and decomposition was performed. Thin films of ZnO have been obtained by thermal treatment of the MAPLE obtained thin films, according to the thermal analysis and decomposition kinetics of zinc benzoate. The obtained morphologies, before and after thermal treatment, have been investigated by atomic force microscopy (AFM).

For two typical actuators of intelligent systems (Ni–Ti SMA cantilever and SMA helical spring), the evaluation of their thermal characteristics is presented. In order to determine the transformation temperatures and other thermal parameters of the two studied elements, the attention was concentrated on thermal analysis experiments. For each actuator configuration, comprehensive graphical interfaces have been developed, to run in Visual Basic, with respect to the results of performed thermal analyses.

Thermal analysis of 2-allyl-4-((4-(4-methylbenzyloxy)phenyl)diazenyl)phenol dye was performed in air flow. The compound thermal behavior was investigated using TG, DTG and DSC techniques, under non-isothermal linear regime. Kinetic parameters of the two decomposition steps were obtained by means of multi-heating rates methods. Isoconversioanl methods (KAS and FWO), Invariant Kinetic Parameters method and Perez-Maqueda et al. criterion (by means of CR and FW equations) were used.

Thin films of [Cd{SSi(O–Bu t ) 3 }(S 2 CNEt 2 )] 2 , precursor for semiconducting CdS layers, were deposited on silicon substrates by Matrix-Assisted Pulsed Laser Evaporation (MAPLE) technique. Structural analysis of the obtained films by Fourier transform infrared spectroscopy (FTIR) confirmed the viability of the procedure. After the deposition of the coordination complex, the layers are manufactured by appropriate thermal treatment of the system (thin film and substrate), according to the thermal analysis of the compound. Surface morphology of the thin films was investigated by atomic force microscopy (AFM) and spectroscopic-ellipsometry (SE) measurements.

Thermal analysis of [4-(4-chlorobenzyloxy)-3-methylphenyl]( p -tolyl)diazene dye, was performed in dynamic air atmosphere. The compound behavior was investigated using TG, DTG, DTA and DSC techniques, under non-isothermal linear regime. Kinetic parameters of the two decomposition steps were evaluated by means of multi-heating rates methods, such as “mode-free” kinetic methods, IKP method, Perez-Maqueda et al. criterion and Master plot procedure. It was shown that the conversion function which describes the process it is not necessary one of the best-fitting functions (when using single-heating rate methods). IKP method can however reduce the possibilities of choosing the true function which can be precisely obtained by applying discrimination methods.

Advanced software (TKS-SP2.0 version) for thermal and kinetic analysis, for determining the non-isothermal kinetic parameters of heterogeneous processes has been developed. The dynamic handle of conversion degree steps and ranges, heating rates and kinetic models, makes the evaluation of the kinetic parameters much faster, for TG, TPR and dilatometry experiments. The standard procedure for evaluating the kinetic triplet was implemented; several linear isoconversional methods (from generalized KAS to FWO, Li-Tang and Friedmann methods), IKP method, Perez-Maqueda et al. criterion (both by Differential equation) and Master plots method. The software is designed mainly for data processing of experimental files, but may also import other already transformed numeric data.

A software package to determine the non-isothermal kinetic parameters of heterogeneous reactions has been developed. The dynamic handle of conversion degree step and ranges, heating rates and kinetic models makes the evaluation of the activation parameters much faster. The standard procedure: ‘model-free’ kineitc, IKP and Perez-Maqueda et al. methods, is applied for the determination of the kinetic triplet corresponding to thermal induced transformations. The software is designed mainly for thermogravimetric, temperature programmed reduction and dilatometry data processing, but may also import already transformed numeric data.

Thermal analysis of 4-[(4-chlorobenzyl)oxy]-4′-chloro-azobenzene dye, exhibiting liquid crystalline properties, was performed in dynamic air atmosphere. The compound behavior was investigated using TG, DTG, DTA and DSC techniques, under non-isothermal linear regime. The evolved gases were analyzed by FTIR spectroscopy. Kinetic parameters of the first decomposition step were obtained by means of multi-heating rates methods, such as isoconversioanl methods, IKP method and Perez-Maqueda et al. criterion.

A new synthesized 4CN type azomonoether, exhibiting dying properties, crystalline nature and generating interest as a material for non-linear optical applications was investigated. Modern devices incorporating liquid crystals tend to use thin films of such materials because of their special characteristics. Thermal stability studies are indispensable before attempting any deposition experiment. We have investigated the thermal behaviour of 4-[(4-chlorobenzyl)oxy]-4′-cyano-azobenzene (TG, DTG, DTA and DSC) in inert flow atmosphere, under non-isothermal conditions. The phase transitions were studied by repeated heating-cooling regimes, with intercalated isothermal steps. The thin films were deposited on silicon and quartz substrates by matrix assisted pulsed laser evaporation (MAPLE) using a Nd:YAG laser working at 266 nm. FTIR spectroscopy of the obtained thin films confirmed the preservation of the compound’s structure.

Over the ages, the deposits of dead vegetation buried by rock and mudflows, compacted and compressed out all of the moisture; it slowly carbonized and became coal. Humic acids are natural organic acids — brown coloured biological macromolecules, formed in coal by biochemical changes (decomposition, pyrolysis) of lignocellulosic matter. From lignite coal bed, the humates were extracted in alkaline medium and isolated from the residual fraction. Humic acids were obtained by treating humantes’ solutions with HCl. Thermal analysis (TG, DTG, DTA and DSC) was used in order to establish the decomposition and thermal effects of lignite, humates, humic acids and residual matter extracted from Rovinari mines in Romania. A non-isothermal linear temperature regime was imposed to reveal all decomposition steps.

Coordination compounds may be used as efficient precursors for fabrication of semiconducting layers. Thermal stability of such a potential precursor — [Cd{SSi(O-tBu)3}(S2CNEt2)]2 — was investigated (tBu means tert-butyl and Et means ethyl). The kinetic study was performed by means of different multi-heating rate methods: isoconversional (Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose and Friedmann) methods associated with the criterion of the independence of the activation parameters on the heating rate. The kinetic triplet of the non-isothermal decomposition of this Cd(II) complex was established.

A series of new complexes with mixed ligands of the type M(4,4’-dipy)(C3H3O2)2(H2O)y ((1) M=Mn, y=2; (2) M=Ni, y=2; 4,4’-dipy: 4,4’-dipyridyl and C3H3O2 is acrylate anion) and respectively M2(4,4’-dipy)(C3H3O2)4(H2O)y ((3) M=Cu, y=0; (4) M=Zn, y=1). The modification evidenced in IR spectra was correlated with the presence of acrylate ion as unidentate in the case of complex (1) and as bidentate for others complexes. The electronic reflectance spectra showed the d–d transition for complex (1) and (2) characteristic for the octahedral surrounding while the spectrum for complex (3) have the characteristic pattern for square-pyramidal stereochemistry. The thermal behaviour steps were investigated. The thermal transformations are complex processes according to TG and DTG curves including dehydration, acrylate ion oxidative degradation and thermolysis process of aromatic amine. The final products of decomposition are the most stable metal oxides.

The authors would like to acknowledge EaStCHEM and EPSRC for financial support. A series of isovalently A-site substituted relaxor dielectric tetragonal tungsten bronzes of general formula Ba6-x-ySrxCayGaNb9O30 were investigated. The long-range (average) crystal structure as determined by conventional diffraction techniques varies monotonically according to Vegard’s law. The dielectric properties, however, do not display a similar, simple “average size” dependence and instead show a dependence on the statistical size variance, i.e. size mismatch, of the A-cation. The difficulties in Vogel-Fulcher analysis of relative permittivity and the complementary approach of using dielectric loss data fitted to Jonscher’s empirical Universal Dielectric Relaxation model is discussed. Publisher PDF

In-depth analysis of the relaxor behaviour of Ba6MNb9O30 (M= Ga, Sc, In) tetragonal tungsten bronze (TTB) ceramics was carried out. Powder x-ray diffraction and scanning electron microscopy were performed in order to confirm the formation of desired phases and to determine the microstructure. Low-temperature dielectric spectroscopy was used in order to characterise the dielectric properties of these materials; the degree of relaxor behaviour were investigated in relation with the increase of ionic radius of the M-cation on the B-site of the TTB structure. The dynamics of dielectric relaxation of dipoles was studied by fitting the dielectric permittivity data to the Vogel-Fulcher (VF) model in order to monitor the reproducibility and validity of the physical results. Restrictions to the VF fit were attempted besides the regular “free-fit” by constraining some of the fundamental relaxation parameters to physically sensible values. We show that Vogel-Fulcher fits are very sensitive to the fitting range resulting in a large range of fundamental parameters for the dielectric relaxation processes, and that the restriction of the frequency domain due to experimental noise or to instrumentation limits has a dramatic influence on the values obtained. Postprint

Thermal behavior studies of several polymers, i.e. polyvinyl chloride (PVC), polyacrylic acid (PAA), and polyaniline (PAni), together with thin film deposition by a MAPLE technique, are presented. Thermal stability studies are important before attempting any laser-assisted processing of such materials, as this provides a better understanding of their molecular behavior, to assess the evolution and dynamics of the deposition. Thin films were grown on silicon substrates by means of matrix-assisted pulsed laser evaporation (MAPLE) using a Nd:YAG laser (266 and 355 nm, 7 ns pulse duration). Above the fluence of ~0.7 J/cm 2 the polymeric films are highly non-uniform due to the transferring of matrix-droplets and/or clusters from the target. At low fluence, typically between 0.1 and 0.5 J/cm 2 , the polymeric films are intact; the surface morphology is substantially improved and there are no measurable traces of the matrix molecules in the films. The important question of polymeric molecules integrity in the films with respect to that of the targets is discussed, in relation to their properties, and compared to data available in the literature.

The non-isothermal kinetic parameters corresponding to the decomposition of 4-[(4-chlorobenzyl)oxy]-4’-nitro-azobenzene were evaluated. The kinetic analysis was performed by means of different multi-heating rates methods: isoconversional (‘model-free’) (Flynn–Wall–Ozawa), Kissinger–Akahira–Sunose (KAS) and invariant kinetic parameters (IKP) methods associated with the criterion of the independence of activation parameters on the heating rate. The values of the obtained non-isothermal kinetic parameters are in satisfactory agreement.

A new family of relaxor dielectrics with the tetragonal tungsten bronze structure (nominal composition Ba6M3+Nb9O30, M3+ = Ga, Sc or In) were studied using dielectric spectroscopy to probe the dynamic dipole response and correlate this with the crystal structure as determined from powder neutron diffraction. Independent analyses of real and imaginary parts of the complex dielectric function were used to determine characteristic temperature parameters, TVF, and TUDR, respectively. In each composition both these temperatures correlated with the temperature of maximum crystallographic strain, Tc/a determined from diffraction data. The overall behaviour is consistent with dipole freezing and the data indicate that the dipole stability increases with increasing M3+ cation size as a result of increased tetragonality of the unit cell. Crystallographic data suggests that these materials are uniaxial relaxors with the dipole moment predominantly restricted to the B1 cation site in the structure. Possible origins of the relaxor behaviour are discussed., Main article 32 pages, 8 figures; Supplementary data 24 pages, 4 figures

The processes of hyaluronan (HYA) drying and hydration were studied using differential scanning calorimetry. In the first approach the isoconversional Kissinger–Akahita–Sunose (KAS) method was applied in order to determine actual activation energies of evaporation of pure water and water from concentrated HYA solutions. Since the evaporation is a single-step process, the activation energies for pure water provided results consistent with tabulated values of evaporation enthalpies. In the course of water evaporation from hyaluronan solution a break in increasing enthalpy followed by a decrease below 0.34 g of water per 1 g of HYA was observed. This result confirmed earlier observation that at this particular water content evaporation from hyaluronan is compensated by heat evolution associated with the formation of new bonds in hyaluronan supramolecular structure. Subtraction of water evaporation enthalpy from enthalpies obtained for HYA concentrated solution provided a possibility to extrapolate the evaporation enthalpies to the concentration (approximately 2 g of water per 1 g of HYA) at which free water is not present any longer and only bound water starts being evaporated from the HYA solution. Similar results were obtained in the second approach in which using slightly modified “traditional” freezing/thawing experiment, melting enthalpy of ice was plotted against water fraction in HYA. It was found out that the melting enthalpy of ice exponentially increases from 0.8 up to 2 g of water per g of hyaluronan where it reaches and keeps the melting enthalpy of hexagonal ice. It was shown that both approaches can serve as alternatives providing an additional insight into the state of water and biopolymers in highly concentrated solutions.

Andrei Rotaru was born on the 9th of August 1983 in Craiova, Romania. Since November 2006, he is working at the National Institute for Laser, Plasma and Radiation Physics (INFLPR) Bucharest, Romania, where he currently holds the position of Researcher III (equiv. to Lecturer). Andrei has received his BSc in Chemistry and Physics from the Faculty of Chemistry of the University of Bucharest in 2006, specializing in Physical chemistry. Since 2004, he has carried out research in the field of thermal analysis and kinetics of heterogeneous processes (decomposition of various systems, including liquid crystals and dyes, complex inorganic materials and precursors, biomass and coal). He has also developed a software for performing kinetic computations (TKS-SP) and later on used this knowledge in studying, modelling and processing of thin films by laser-assisted techniques (mainly MAPLE). In 2007, Andrei has received an EPSRC grant, followed by a prestigious fellowship of the Roberto Rocca ‘‘Educational Program’’ for his doctoral studies in solid-state chemistry of ceramic materials at the University of St Andrews, United Kingdom. These more recent interests are related to the fabrication, thermal processing and characterization of novel electroceramic materials with tetragonal tungsten bronze structure. In general, a special interest was directed on modelling relaxation processes in polar dielectric ceramics and investigating the structure–properties relations to induce and control ferroelectricity and ferromagnetism. In 2011, he was the co-chairman of the 1st Central and East European Conference on Thermal Analysis and Calorimetry (CEEC-TAC1), and in 2008 a member of the scientific committee of the 14th International Congress on Thermal Analysis and Calorimetry (ICTAC14) in Brazil; he is a member of the International Confederation for Thermal Analysis and Calorimetry (ICTAC), Commission for Thermal Analysis and Calorimetry of the Romanian Academy (CATCAR), Kinetics committee at ICTAC, International Society for Optics and Photonics (SPIE), and president of the Central and Eastern European Committee for Thermal Analysis and Calorimetry (CEEC-TAC). Currently, he acts as an editor for thermal analysis at the Global Journal of Analytical Chemistry and as a reviewer for several journals: The Journal of Physical Chemistry, Journal of Thermal Analysis and Calorimetry, Thermochimica Acta, Journal of Applied Polymer Science, Dyes & Pigments, Chemical Industry & Chemical Engineering Quarterly, etc. Andrei has been an invited lecturer at several universities and institutes from Lithuania, Estonia, Slovakia, Czech Republic, Poland, and is directly involved and interested in A. Rotaru (&) INFLPR – National Institute for Laser, Plasma and Radiation Physics, Bvd. Atomistilor, nr 409, Magurele (Ilfov), Bucharest, Romania e-mail: andrei.rotaru@inflpr.ro Name: A. Rotaru

We discuss the strategy for development of novel functional materials with the tetragonal tungsten bronze structure. From the starting composition Ba 6 GaNb 9 O 30 , the effect of A- and B-site substitutions on the dielectric properties is used to develop an understanding of the origin and stability of the dipolar response in these compounds. Both tetragonal strain induced by large B-site cations and local strain variations created by isovalent A-site substitutions enhance dipole stability but result in a dilute, weakly correlated dipolar response and canonical relaxor behaviour. Decreasing cation size at the perovskite A2-site increases the dipolar displacements in the surrounding octahedra, but insufficiently to result in dipole ordering. Mechanisms introducing small A-site lanthanide cations and incorporation of A-site vacancies to induce ferroelectricity and magnetism are presented.

Quantum dots (QDs) are semiconducting nanoparticles interesting due to their size- dependent optoelectronic properties. Cadmium selenide QDs are generally used in photovoltaic applications due to their tuneable bandgap. Various physical and chemical methods can be used for QDs preparation but chemical routes are more advantageous due to facile QDs shape and size control. However, when preparing thin-films from colloidal QDs, obtaining satisfactory geometry arises as the main obstacle due to particle aggregation. The former can can be prevented by applying surface modification agent during the course of the synthesis. Here we compare two methods for surface modification of colloidal CdSe QDs in the course of the layer-by-layer (LbL) deposition of thin- films ; (i) by ligand exchange and (ii) by silanization. Also, the impact of the solution temperature was also considered. Firstly, the prepared precursor solutions were injected into the growth solution. Longer reaction time resulted in bigger CdSe QD with narrower bandgaps. Surface was modified by: (i) ligand exchange of trioctylphosphine (i) silanization with tetraethoxy silane. Then the thin-films of CdSe QDs were created by LbL with varying several solution temperatures and number of layers. The linking layers for silanized and exchanged ligands QDs were (3-aminopropyl)triethoxysilane and poly(diallyldimethylammonium chloride). Layers were connected via electrostatic assembly or through hydrogen bonding and condensation reactions. Colloidal QDs solutions and derived thin-films were examined using dedicated structural analysis and combination of spectroscopic, morphologic and microscopic techniques. The analyses confirmed successful silanization, i.e. interconnecting of the QDs into thin-films. Testing confirms that morphology, surface roughness, thin-film thickness and appropriate distribution of the QD domains remain due to careful ligand exchange in solution stage, pointing out in thermally stable films without aggregation-based defunctionalisation. [1] J. Li, J. Chen, Y. Shen, X. Peng, Nano Res., 11 (2018) 3991-4004 [2] K. Surana, P.K. Singh, H.W. Rhee, B. Bhattacharya, J. Ind. Eng. Chem., 6 (2014) 1-6 [3] B.K. Pong, B.L. Trout, J.Y. Lee, Langmuir, 24 (2008) 5270-5276 [4] X. Liu, J. Han, W. Wu, Q. Shi, W. Li, C. Li, Chem. Lett., 45 (2016) 10-12

Gas sensors require materials with vapour sensitive surface, photocatalytic systems require materials with oxygen sensitive surface, photovoltaic devices require materials with photon sensitive surface [1]. For all of the mentioned purposes, different metal oxides forming semiconducting materials are found to be convenient due to their sometimes very unique specific properties but also ability to conduct a low price synthesis, to derive a robust material, which undergoes reactions over known mechanisms and thereof are widely applicable. N-type semiconductors are known for somewhat faster reactivity leading to considerably lower amount of p-type semiconductor-related reports. Among those, a cobalt oxide spinel is found. Here, a simple solvothermal method was applied to derive Co3O4 nanomaterial using cobalt nitrate and ammonia as precursors. Structurally monophasic Co3O4 nanoparticles with spinel structure were indicated by powder X-ray diffraction crystallisation of while the presence of traces of organic phase residuals in otherwise chemically homogeneous material was observed by Fourier-transformed infra-red spectroscopy. Scanning electron microscopy further shows that the observed fine nanoparticulate matter forms agglomerates with possible presence of rod-like formations. Interestingly, using transmission electron microscopy it was possible to reveal that the agglomerates of the fine nanoparticulated material is actually nanostructured, i.e. the presence of 1D-shaped Co3O4 rods embedded in fine nanoparticulated matrix are confirmed. In conjunction with the N2 adsorption/desorption isotherms, the discussion about the orientation, exposure of nanostructured rod domains and derivative geometry parameters was possible. The nanostructured Co3O4 material was shown to be stable up to 800 °C whereat the decomposition to CoO takes place. The specific surface area of nanostructured sample was raised, so it was interesting to investigate photocatalytic efficiency. For that matter just a simple degradation tests using the basic model pollutant methylene blue were performed ; results suggest that the degradation performance of prepared nanostructured Co3O4 photocatalyst having above- mentioned properties is worth deeper investigation.

Modern solid-state solar cells are multi-layered composites ; such configuration allows immense area for upgrades but not without struggle. As the main problem of all modern photovoltaic devices we find the mutual dependence of layers, i.e. the difficulty to predict the exact behaviour due to complex transport mechanisms at the boundaries between thin-film interfaced to other layers. Among such constituents, we find transparent electrodes or transparent conducting oxide layers (TCO), primarily aluminium doped zincite (AZO). AZO is a system thought to be well known, yet synthesis and deposition, chemical modifications, nano-morphological and nano-structural organisation parameters are still not unambiguously related to final functionality. For example, it is not clear how nanostructurisation of AZO would affect light trapping and vertical conductivity, while retaining of lateral conductivity for same thickness of films. The questions regarding general compatibility in interfacing of adjacent layers in SC also remain unclear. The benefits of AZO are thermal stability and mild deposition conditions. We follow these benefits and here we show evaluation of various softer chemical deposition methods for preparing AZO in planar configuration, as well as nanostructured, vertically aligned AZNR films that will retain conductivity, transparency and layer interconnectivity. The successfulness of the synthesis method was checked by means of GIXRD, FTIR-ATR and SEM/EDS. PL/DRS-UV-VIS and DLTS monitored compositional parameters behind transparency as well as lateral and perpendicular conductivity. In addition, parameters from profilometry, contact angle and TEM/EELS analysis shed more light on what synthesis seem to be more favourable for specific property. The utilisation of the observed parameters and behaviour was discussed from the point of view of TCO and CTO performing solar cell layers. The concept of developed material may shift the strategies of the solar cell design. This investigation of AZNR may cause the reconsideration of the paradigm of solar cell assembly since the AZNR additionally show conceptual similarities with charge transfer oxide (CTO) layers.

Hexaferrites are a class of iron compounds which crystalize in a sandwich-like periodic stacking of iron-oxide layers containing different metal atoms. The simplest is the M-type with chemical formula AB12O19, where A = Ba, Pb ... and B = Fe, Ti ... Our recent measurements with frequency-dependent magnetic susceptibility technique on various substitutions within the M-type hexaferrite (Ba1−xPbxFe12−yAlyO19) has shown signatures of exotic phenomena which point toward a general relaxational mechanism in ferrimagnetic semiconductors. Moreover, it was shown that activation energies of relaxation dynamics increase by adding aluminum. Heat capacity measurements from room temperature down to liquid helium indicate that the whole temperature range can be fitted well by the Debye and Einstein contributions up to room temperature. The energy of the lowest Einstein mode came close to the energy of the Debye mode.

Binding of drugs to proteins influence their pharmacokinetic and pharmacodynamics action. In the blood, the drug is distributed in the body in the free form or bound to plasma protein. α1-acid glycoprotein (AGP, also known as orosomucoid) is an important plasma protein involved in the binding and transport of many drugs, particularly basic one such as imatinib (IMT), a selective tyrosine kinase inhibitor, successfully used for the treatment of chronic myelogenous leukaemia and gastrointestinal stromal tumors [1-2]. This research uses sensitive and modern isothermal titration calorimetry (ITC) technique for characterization of microscopic thermodynamic parameters that trigger the binding of drugs to AGP. ITC is a convenient and widely used experimental technique to directly measure released or absorbed heat during association processes such as protein-drug interaction and to quantitatively measure the binding affinity [3]. The main goal of this research is to quantitatively evaluate the interaction between imatinib mesylate and AGP to characterize the nature and forces underlying the formation of a protein-drug complex. The binding of basic drug imatinib displayed an exothermically driven binding interaction with AGP. Binding energy was guided by a combination of favorable (negative) enthalpy (ΔrH = –4.21 kcal/mol) and favorable (positive) entropy (ΔrS = 3.62 kcal/mol K) contribution to the Gibbs free energy (ΔrG = –7.82 kcal/mol) with association constant (KA = 17.6 x 10-2 μM-1). Enthalpy change is an important step in understanding the driving forces that characterize the protein-drug interaction information very much needed in the drug discovery process.

Transparent conductive thin-films have received much attention due to their high conductivity and transmittance as well as broad areas of use (optoelectronic devices, e.g. solar cells). In comparison to the widely used indium tin oxide (ITO) films, aluminium doped zinc oxide (AZO) films represent a low cost alternative that can be easily deposited by a variety of chemical and physical methods [1, 2]. In order to determine the optimal conditions for obtaining films that can be used as transparent conductive oxide layers (TCO) we investigated the course of preparing AZO films by DC magnetron sputtering using two source targets: zincite (ZnO) and aluminium (Al). DC power was varied during the deposition on glass substrates and derived films were subsequently thermally treated. All films display hexagonal wurtzite structure of zincite regardless of the deposition parameters as shown by X-ray diffraction analysis (XRD). The average transmittance of the films was more than 85% in the visible range (400 to 800 nm). The Al content and thermal treatment were responsible for variations of the average grain size and achieved morphology, which was confirmed by electron and atomic force microscopies (SEM and AFM) as well as synchrotron radiation scattering experiments (SAXS). Finally, solid state dielectric spectroscopy measurements (SS IS) described the development of electrical conductivity with temperature in the prepared thin-films. It was found that the optimisations of the thermal processing play a key role in tailoring of layers with advanced charge transport functionalities. The investigation brings to conclusion that application of the subsequent thermal processing can improve both electrical and optical properties of the AZO films derived by magnetron sputtering.

Polylactic acid (PLA) has become interesting for research because of its possible use in various application fields due to its biodegradability. PLA belongs to the polymers derived from the renewable resources such as sugar cane corn. The application of this polymer, as well as other polymers, is often limited by their flammability. This problem can be solved by adding flame retardants. Flame retardants should prevent the start of the combustion reaction or quickly stop the reaction if it has already begun. Magnesium hydroxide (Mg(OH)2) is an environmentally friendly metal hydroxide that is increasingly used as a functional inorganic filler and in this case as a flame retardant for PLA. Mg(OH)2 is possible to produce by extraction from ores, such as magnesite, dolomite, or serpentinite, and from brine/seawater [1]. Inorganic fillers are often surface modified for better interaction with a polymer, i.e. better adhesion, and hence better polymer properties. The aim of this study was to prepare PLA/modified Mg(OH)2 composites of the satisfactory thermal properties and the thermal stability to extend the PLA application field. Mg(OH)2 was obtained from seawater as an unlimited source of this material. Modification of Mg(OH)2 was performed with 5 and 10% of stearic acid relative to the hydroxide. Using infrared spectroscopy with Fourier transformation (FT-IR) successful chemisorption of stearic acid on the filler surface was confirmed, after which two series of PLA/modified Mg(OH)2 composites were prepared using a laboratory single-screw extruder. The amount of the modified Mg(OH)2 was up to 20 wt %. Differential scanning calorimetry (DSC) was used to investigate the effect of the modified filler on the thermal properties of PLA. Addition of the modified inorganic filler has a complex effect on the PLA thermal properties, with a clear reduction in PLA crystallinity for both composite series. Thus, modified Mg(OH)2 doesn’t act as a nucleation agent in the PLA composites. The amount of stearic acid doesn’t make noticeable influence on the thermal characteristics of PLA. The thermal stability of the composites was investigated using thermogravimetry (TG). PLA degrades in one degradation stage and the both modified Mg(OH)2 in two. The both PLA/modified Mg(OH)2 composite series degrades up to four degradation stages. With the increase of the modified Mg(OH)2 content in both composite series their decomposition becomes the more complex and the thermal stability of PLA is getting worse. Different amounts of stearic acid used for filler modification didn’t produce any influence on the thermal stability of PLA.

Poster Session 1 : Materials, Chemicals, Thin films & Nanomaterials, Thermal Processing and Applications - ISBN 978-3-940237-50-7; International audience; Gypsum is the mineralogical used term to describe materials that are mainly constituted of calcium sulfate dihydrate (CaSO4.2H20). The calcination of gypsum, i.e. the dehydration of gypsum under solid-gas conditions, is of great technological importance because it represents the main industrial process for the production of plaster, the inorganic material with the largest production in the world. Plaster, in turn, is mainly constituted of calcium sulfate hemihydrate (CaSO4.0.5H20). In spite of the significance of these materials for this and other scientific fields, some important aspects of the chemical system CaSO4- H20 are still unknown. In particular, the water content within the gypsum calcination products is only partially described in the literature.This absence of a complete understanding of this system despite its importance and the fact Chat these materials have been used since antiquity can be attributed to several phenomena Chat contribute to its complexity. First of ail, the literature acknowledges the existence of several calcium sulfate polymorphs. For instance, the dehydration of gypsum can lead to different calcium sulfate hydrates of the form CaSO4•&#949H2O, where &#949 can be 0.625, 0.5, or 0, depending on the temperature (T) and water vapor partial pressure (P) under which the reaction takes place. Moreover, these compounds can also present zones of divariance, i.e., domains where the overall water content of these hydrates can change continuously with T and P. The fine knowledge of the stability domain of each species throughout successive thermal transformations of the CaSO4.2H20 is still debatable. In this context, the objective of the present work is to determine the stability conditions and domains for the CaS04.2H20 dehydration products. Furthermore, the nature of the divariant behavior is also investigated. Thermogravimetric analysis under isotherm and isobaric conditions using different protocols with temperature ranges of 30°C to 250°C and water vapor partial pressure ranges of 5 hPa to 60 hPa was performed. The results allowed the determination of two zones of divariance and one univariant domain. The variations of the measured water contents in contrast with the stoichiometry of each polymorph were interpreted with models adapted for each zone. Finally, a phase diagram P-T is proposed based on the stability domain of each phase, and values of change in enthalpy and entropy of reaction were obtained for each transformation and compared with previously published values.

ISBN 978-3-940237-50-7 / Oral Presentations 4: Chemicals, Polymers, Bio(macro)molecules & Biocomposites, Life science, Organic & Functional complex compounds; International audience; Among the processes Chat could be used to synthesize actinide oxides for nuclear fuel rcycling purpose, one well-known method is the thermal treatment of actinide oxalates under controlled atmosphere. In fact, the actinide is first stabilized by a precipitation step, then the actinide oxalate is calcined in order to obtain an oxide powder to be shaped and sintered during the fabrication process. The transformation of actinide oxalate into the final oxide consists in a succession of transformations modifying the characteristics of the solid such as composition, specific surface area, granulometry, impurity content,... The thermal treatment leads to a complex evolution of the solid phase with some gaseous releases. A better understanding of gas-gas and gas-solid reactions is essential to be able to predict the final characteristics of the oxide according to the thermal parameters. In this work we used differential scanning calorimetry and thermogravimetric analysis with evolved gas analysis in order to investigate the thermal behavior of uranium oxalate in various atmospheres. Contrary to previous studies, a set of solids characterizations (morphological, textural and structural) was used to unambiguously indentify the reaction products. Among the seven stages involved during the global reaction, the kinetics of two of them were specifically investigated. The experimental kinetic data in isobaric and isothermal conditions are explained thanks to kinetic modelling based on the characterizations of solid and heterogeneous kinetics approach. This allows us to obtain predictive model which includes the effect of temperature and partial pressure of some gases of interest, as well as the shape and size of the solid phases.

Oral Presentations 2 : Theory & Methods, Kinetics & Catalysis, Fuels & Biofuels, Energetics and Applied Thermal Engineering - ISBN 978-3-940237-50-7; International audience; Thermal decomposition of Cu(OH)2 exhibits specific physico-geometric kinetic characteristics involving the significant induction period (IP) and subsequent sigmoidal mass-loss behaviour under isothermal conditions and the two-step mass-loss process with a long lasting reaction tail under linearly increasing temperature conditions. In addition, the rate behaviours of IP and mass-loss process are largely influenced by the environmental water vapour pressure, p(H20). The IP at a constant temperature is prolonged with increasing p(H20). The mass-loss curves shift systematically to higher temperatures with increasing p(H20). Therefore, the kinetic approach to this complex reaction requires the detailed considerations of the mechanistic features and the impact of p(H20).For the universal kinetic approach to each kinetic process under different p(H20), an accommodation function with respect to p(H20) was derived: cf. file abstract. The accommodation function a(p(H20), Peq(T)) can be introduced into different kinetic equations for describing the IP and mass-loss process. The IP at different temperatures and under different p(H20) analysed kinetically by a single Arrhenius-type plot, providing a statistically significant linearity and the activation energy Ea,IP = 243 ± 13 kJ mol-1. Similarly, a(p(H20), Peq(T)) is introduced into the isoconversional kinetic equation for analyzing universally the mass-loss process under different temperature conditions and p(H20). The isoconversional plots applied to the major mass-loss step of the thermal decomposition of Cu(OH)2 represent straight lines and the average Ea,l = 148 ± 1 kJ mol-l (Fig. 1) (cf. file abstract). Furthermore, the overall thermal decomposition of Cu(OH)2 under isothermal conditions can be described by the IP-surface reaction (SR)-phase boundary controlled reaction (PBR) model. The rate constants of each component reaction step determined under different p(H20) are subjected to the Arrhenius plot by considering a(p(H20), Peq(T)).

ISBN 978-3-940237-50-7Poster Session 1: Materials, Chemicals, Thin films & Nanomaterials, Thermal Processing and Applications; International audience; Greenhouse gas emissions, in particular carbon dioxide, are considered as the main causes of the global warming. So, capture and storage of C02 coming from industrial installation are major environmental objectives. One way of C02 separation and capture is to use carbonation/decarbonation cycles on various capture masses. Among numerous candidates, magnesium oxide presents the advantage to form a thermodynamically stable carbonate, to be regenerable by simple heating, and to be available in large quantifies and at low-cost. If magnesium oxide has been largely studied for applications in catalysis, its use as C02 capture mass remains misunderstood. Thus the reaction of MgO carbonation made the object of few studies, and the main ones deal with utilization at high temperatures (300-350°C) and high C02 pressures (10-20 bar). In this work, we are interested in both the synthesis of magnesium oxide with high specific surface area, and its carbonation properties at atmospheric pressure. The way of synthesis of a mesoporous magnesium oxide is described, as well as the physico-chemical characterizations of such an oxide. The reaction of carbonation is followed by means of thermogravimetric experiments. The influences of temperature, C02 partial pressure and water vapor partial pressure are investigated. These results are completed by the characterizations of texture and morphological properties of the solid and their change during the reaction.

ISBN 978-3-940237-50-7 / Poster Session 1: Materials, Chemicals, Thin films & Nanomaterials, Thermal Processing and Applications; International audience; Within the framework of the recycling of the valuable materials (actinides U, Pu) from irradiated nuclear fuel, the conversion is an important stage which is involved between both separation / purification processes and the steps of manufacturing of mixed fuel such as MOx. Thus this stage must be able to integrate purification flows while leading to oxides or mixtures of oxides adapted to the fuel shaping. These needs are even more marked with the deployment of the reactors of 4th generation and involve the development of new processes of conversion to take into account problems characteristic of this technological breakthrough (e.g. higher cadence, Pu content, liquid and gaseous effluents management, etc.).To answer these future needs, new ways of synthesis were identified by the CEA, from the short-term adaptation of already existing ways based on the oxalic conversion, to more innovative ways requiring a longer-term R&D. In this context, the way of oxalic co-conversion is investigated via the ANR ASTUTE project. The mixed oxalate obtained by precipitation undergoes a heat treatment to obtain mixed oxide. This heat treatment is then a key stage because it allows to control most of the morphological, textural and chemical final characteristics of the oxide. These characteristics are fundamental for the following stage which consists to the fuel manufacturing.During this thermal conversion, a series of transformations take place before obtaining the final oxide. So as to predict and thus master the characteristics of this solid, a fine knowledge of the reactional scheme during the heat treatment is necessary. The use of thermogravimetry in both controlled temperature program and isothermal conditions in the case of a uranium-cerium mixed oxalate allowed to isolate reactional intermediates during the conversion of the oxalate in oxide. These intermediates were characterized by chemical (IRTF spectroscopy), morphological (SEM) and textural (specific surface area and porous volume) point of view. By this way, a reaction scheme is proposed. A deep knowledge of such a reaction scheme including the intermediate solids is essential to identify the key transformations and determine their kinetic: behavior.

Oral Presentations 2 : Theory & Methods, Kinetics & Catalysis, Fuels & Biofuels, Energetics and Applied Thermal Engineering - ISBN 978-3-940237-50-7; International audience; Gypsum is the mineralogical term used to describe materials that are mainly constituted of calcium sulfate dihydrate (CaSO4.2H20). The calcination of gypsum to produce plaster is a large -scale industrial process with paramount importance for the modern construction materials industry. During this process, two main dehydration reactions usually occur during calcination depending on temperature and humidity conditions: CaSO4.2H2O dehydrates to hemihydrate (CaSO4.0.5H20) and the latter can also dehydrate forming soluble anhydrite (CaS04). Despite the fact Chat the literature in gypsum dehydration is considerably extensive, there is a substantial lack in accordance about several aspects of the aforementioned dehydration reactions. For instance, there is no accordance if the type of kinetic model to be used to describe the reaction needs to take accourt of both nucleation and growth or only one of these processes. Furthermore, when the nucleation and growth processes are considered, the JMAEK model is generally used, which lacks in physical meaning for solid-gas reactions. In addition, as there is no accordance concerning the employed kinetic models, published reaction mechanisms and apparent activation energy values also Biffer. Hence, the lack in accordance about several aspects of these reactions makes it necessary to investigate in detail the intrinsic chemical reactivity of this system. In this context, one of the objectives of the present work is to describe and analyze with precision the different solid-gas transformations within the chemical system CaSO4-H20 and clarify remaining questions on reaction kinetics still present in the literature. In order to perform this, the dehydration of a highly pure calcium sulfate dihydrate powder was monitored using thermogravimetric analysis under isotherm and isobaric conditions to obtain kinetic curves. Temperature ranging from 30°C to 250°C and water vapor partial pressure ranging from of 5 hPa to 60 hPa were investigated. Morphological and textural characterizations of the solids were also employed to understand the way of transformation. Based on this knowledge, a kinetic nucleation-growth model was then proposed and applied to the experimental data in order to obtain kinetic parameters for nucleation and growth. A growth mechanism was written and the change of kinetic parameters with temperature and water vapor partial pressure was explained.

The influence of poly(ethylene glycol) (PEG) addition on thermal characteristics and thermal degradation of poly(vinyl chloride)/poly(ethylene oxide) (PVC/PEO) blends was investigated by differential scanning calorimetry and dynamic thermogravimetry. The thermal degradation characteristics of PEO remain unchanged upon PEG addition, while for all other investigated blends their values decreased, particularly at higher PVC content. Kinetic analysis of the non-isothermal degradation of investigated PVC/PEO/PEG blends was performed using isoconversional Friedman (FR) method in combination with the multivariate non-linear regression method. The PEG addition lowers the values of the activation energies of PVC/PEO blends. The kinetic analysis indicated four-stage degradation mechanism for all investigated blends.

Poly(ethylene oxide)/lithium montmorillonite (PEO/LiMMT) nanocomposites have been prepared by melt intercalation and non-isothermally degraded in nitrogen atmosphere [1]. The obtained non-isothermal data have been used in this work for the kinetic analysis of the degradation process. Kinetic analysis was performed using isoconversional Friedman (FR) method in combination with the multivariate non-linear regression method incorporated in Netzsch Thermokinetics Professional software. Our earlier investigations have shown that thermal degradation of PEO is simple (one-step) process [1] while thermal degradation of PEO/LiMMT nanocomposites is complex (multi-step) process that may involve several overlapping or consecutive processes [2]. Kinetic analysis performed for the purpose of this work revealed the complexity of the thermal degradation process for both pure PEO and all PEO/LiMMT nanocomposites. The contribution of the each individual process has been determined and each of them was independently analyzed. Kinetic parameters (activation energy, pre-exponential factor and kinetic model) have also been calculated for each degradation stage of all investigated samples.