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This study utilizes a multidisciplinary approach, combining simulation experiments, thermal expansion analysis, XRD, SEM, and physical property assessments to investigate the firing temperature in illitic-kaolinitic porcelain. Our findings indicate that the accuracy of the thermal expansion method depends on both the actual firing temperature and dwell time. When dwell time is uncertain, the method provides a range of possible actual firing temperatures, differing by approximately 100 °C. Remarkably, as the porcelain body nears full vitrification, the determined firing temperature tends to be notably higher. A critical analysis of previous research suggests potential overestimation of ancient kiln temperatures. Additionally, our study highlights the usefulness of bulk density, water absorption, porosity, and mullite content in determining dwell time. Overall, our research offers new insights into ancient porcelain firing processes. [ABSTRACT FROM AUTHOR]

Summary: In frozen part‐baked bread technology, starch is influenced by various processing factors. This study aimed to investigate the effect of part‐baking time, freezing rate and frozen storage time on pasting, thermal and structural properties of part‐baked bread. Wheat dough was part‐baked for 0, 3 or 6 min and frozen at −20 °C using two freezing rates: slow (0.15 °C min−1) or fast (1.45 °C min−1). Next, samples were stored in frozen conditions for 56 days and analysed every 14 days for starch damage, pasting properties, thermal and X‐ray analysis. The level of damaged starch increased with 3 min (69.3%), and 6 min (88.8%) of part‐baking time for both freezing rates compared to no part‐baked. In pasting analyses, peak viscosity decreased 27.3% and 38.4% for 3 and 6 min of part‐baking time, respectively, at 0 days of frozen storage; however, this tendency was observed for all frozen storage time. The gelatinisation enthalpy (ΔHg) decreased as part‐baking time increased, showing the maximum reduction at 6 min of part‐baked (94.9%). In X‐ray diffraction analyses at 3 and 6 min of part‐baking, the intensity of the signal increased 4.4% and 10.9%, respectively, probably due to the starch gelatinisation. These results can serve as a valuable guide for developing strategies to enhance the quality of part‐baked bread and improve production performance. [ABSTRACT FROM AUTHOR]

The utilization of natural fibers rather than engineered filaments has turned into a subject of conversation in the composite industries. In this research, one of the natural fibers was synthesized from Pennisetum orientale grass and the surfaces were modified using sodium hydroxide (NaOH) chemically. Then they were used as reinforcement in vinyl ester polymer by different weight percentage (0, 5, 10, 15, 20, 25, and 30 wt%) for fabrication of composites. At different filler loading various mechanical properties were evaluated and discussed. The mechanical properties of the composites were observed to increase at beginning phase with increase in filler content till optimum (25 wt%) fiber loading and from there on declines. The composite at optimum fiber loading were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis and compared with untreated composites. The findings give manufactures and engineer a general idea to use this composite for weight reduction especially in automotive applications. [ABSTRACT FROM AUTHOR]

The formation, and subsequent structural, thermal and adsorptive properties of single‐component metal–organic framework crystal‐glass composites (MOF‐CGCs) are investigated. A series of novel materials exhibiting chemically identical glassy and crystalline phases within the same material were produced, where crystalline ZIF‐62(Zn) was incorporated within an agZIF‐62(Zn) matrix. X‐ray diffraction showed that the crystalline phase was still present after heating to above the glass transition temperature of agZIF‐62(Zn), and interfacial compatibility between the crystalline and glassy phases was investigated using a mixed‐metal (ZIF‐62(Co))0.5(agZIF‐62(Zn))0.5 analogue. CO2 gas adsorption measurements showed that the CO2 uptakes of the MOF‐CGCs were between those of the crystalline and glassy phases. [ABSTRACT FROM AUTHOR]

In the RE-Ru-Al systems, in the region with high content of rare earth elements a number of isostructural compounds RE 10 RuAl 3 (RE = Gd, Tb, Dy, Ho, Er, Tm) were identified. The structures of the obtained compounds belong to ordered variant of anti -Co 2 Al 5 -type with a hexagonal cell, space group P 6 3 / mmc (No. 194), Pearson symbol hP 28 , Z = 2, the cell parameters a = 9.5901(19) Å, c = 9.6504(17) Å (Gd); a = 9.5029(17) Å, c = 9.5746(20) Å (Tb); a = 9.4761(17) Å, c = 9.5544(13) Å (Dy); a = 9.4235(9) Å, c = 9.5132(7) Å (Ho); a = 9.3967(6) Å, c = 9.4761(5) Å (Er); a = 9.3589(12) Å, c = 9.4277(10) Å (Tm). All compounds were synthesized by arc-melting the stoichiometric quantities of elementary components. The structures were determined by X-ray diffraction analysis of a single crystal and refined by the Rietveld method from powder X-ray diffraction patterns. In the structure of the compound Ho 10 RuAl 3 one of the three holmium sites - Ho3 - was mixed with Al, which is reflected in the composition of the intermetallide: compound with Ho shows a small deviation from composition RE 10 RuAl 3 and an adequate formula of the compound is Ho 10‒x RuAl 3+x (x = 0.07). The crystal structure of the compounds can be represented as rows of trigonal prisms with rare earth atoms at the vertices, centered by ruthenium atoms, alternating with a pair of empty octahedra of rare earth atoms along the direction c of the unit cell. Rows of prisms and octahedrons separate distorted icosahedrons RE[Al 6 RE 6 ] with a rare earth atom in the center, connected by common triangular faces. All obtained compounds have a congruent melting pattern. [Display omitted] • Six novel ternary intermetallic compounds RE 10 RuAl 3 (RE = Gd, Tb, Dy, Ho, Er, Tm) were prepared. • Two fundamentally different ways of describing the crystal structure of the obtained compounds were considered. • Compound Ho 10 RuAl 3 is characterized by a mixed occupancy of one of the holmium sites by aluminum and holmium atoms. • Intermetallic compounds RE 10 RuAl 3 (RE = Gd, Tb, Dy, Ho, Er, Tm) melt congruently. [ABSTRACT FROM AUTHOR]

AgCu 1 − x Fe x S compounds were synthesized by partial Cu → Fe replacement in the AgCuS crystal at a concentration range of 0 ≤ x ≤ 0.03. In the differential thermal analysis spectrum obtained at a temperature range of 300 K ≤ T ≤ 1300 K, endoeffect corresponding to the structural phase transition in the AgCuS compound was observed at the temperature T = 938 K. It has been determined that this result is also observed in the AgCu 0. 9 9 Fe 0. 0 1 S compound obtained by partial replacement of Cu atoms by Fe atoms. However, in the compound of AgCu 0. 9 7 Fe 0. 0 3 S this effect was observed at higher temperatures. The thermal capacities and enthalpies of phase transitions were calculated for the given compounds. [ABSTRACT FROM AUTHOR]

Carbon nanoparticles (CNPs) are isolated from chimney soot and characterised by various tools such as X‐ray diffraction, scanning electron microscopy, transmission electron microscopy and ultraviolet–visible spectroscopy. The X‐ray diffraction studies confirm the presence of C60 nanoparticles in the isolated sample. The thermal properties of the prepared CNPs are recorded using thermogravimetric analysis and differential thermal analysis. The analysis of the antibacterial activity of the synthesised CNPs against selected Gram‐positive and Gram‐negative bacterial strains is also investigated. The systematic study confirms that CNPs collected from chimney soot exhibit good antibacterial potency against Staphylococcus aureus, Streptococcus pyogenes, Klebsiella pneumoniae, and Proteus mirabilis. [ABSTRACT FROM AUTHOR]

A kind of silicon-and-boron-modified phenolic–formaldehyde resin (SBPF) with excellent thermal stability was fabricated via a simple two-step method and used for the matrix of ablation materials. The structure and thermal stability of the modified phenolic–formaldehyde resins (PFs) were characterised. The results showed that boron and silicon elements have been incorporated into SBPF in the form of a chemical bond. Meanwhile, the cured products showed an increase in graphite structure and a decrease in disordered structure due to the incorporation of boron and silicon. Compared with the ordinary phenolic resin, the initial thermal degradation temperature and charring yield at 800°C of SBPF increased by 73°C and 15 wt%, respectively. Further, the modified PFs, nano-Al(2)O(3) powders, glass powders and vitreous silica fibres were used to obtain a novel ceramizable phenolic moulding composite. The morphology, chemical composition and ablative characteristics of the composites were explored. The results showed that a compact and homogeneous SiO(2)–Al(2)O(3) layer formed on the ablated surface and protected the carbonised matrix and fibres from further oxidation. Compared with the ordinary PF composites, the SBPF composites showed a highly decreased linear/mass ablation rates, indicating the synergistic effect of boron and silicon modification on the enhanced ablation property.

The exploration of new natural fibers in the field of polymer composites can contribute to increase the invention of natural reinforcements and expand their use in possible applications. In the present work, the physico-chemical, thermal, tensile and morphological properties of Furcraea foetida (FF) fiber are presented for the first time. Chemical analysis results shows that FF has relatively higher cellulose (68.35%) with lower hemicelluloses (11.46%) and lignin (12.32%). Structural analysis of FF was conducted by Fourier transform infrared and 13 C (CP-MAS) nuclear magnetic resonance spectroscopy. X-ray diffraction (XRD) analysis evidenced that FF has crystallinity index of 52.6% with crystalline size of 28.36 nmThe surface morphology of FF was investigated by scanning electron microscopy (SEM), energy dispersive X-ray micro analyzer (EDX) and atomic force microscopy (AFM). The thermogravimetric analysis (TGA) reveals thermal constancy of the fiber upto 320.5 °C with the kinetic activation energy of 66.64 kJ/mol, which can be used as reinforcements in thermoplastic green composite whose working temperatures is below 300 °C. The FF results were compared with those of other natural fibers, and indicated as a suitable alternative source for composite manufacture. [ABSTRACT FROM AUTHOR]

Ceramicizable phenolic resin matrix composites are widely used in aerospace fields, and their heat resistance rating can reach 1400 °C. To further improve heat resistance, HfB 2 -SiB 6 ceramicizable phenolic resin matrix composites were prepared, and their thermal properties and oxidative corrosion behaviour were studied. The results showed that the composites with 30 % SiB 6 had a ceramic yield of 69.69 % at 1600 °C, and their linear and mass ablation rates were as low as 0.004 mm/s and 0.043 g/s, respectively. XRD and thermodynamic calculation showed that there were complex reactions to form Hf ceramics and Si-B-N-O to prevent corrosion under high temperatures of about 2000–2400 °C. • HfB 2 -SiB 6 improves the heat resistance of ceramicizable phenolic resin composites. • Composites' linear and mass ablation rates are as low as 0.004 mm/s and 0.043 g/s. • The composites with 30 % SiB 6 have 69.69 % ceramic yield after 1600 °C treatment. • Complex reactions occur to form Hf ceramics and Si-B-N-O preventing corrosion. • Composites have heat resistance at 1600 °C and ablation resistance at 2000–2400 °C. [ABSTRACT FROM AUTHOR]

Phase relationships in the Tb-Al-Si system have been established and experimentally studied at 500 °C. The main experimental techniques used were scanning electron microscopy, electron microprobe analysis and X-ray powder diffraction. Some samples have been analyzed by differential thermal analysis. Six ternary compounds form in the system: the five ternary structures τ-TbAlSi, τ-TbAlSi, τ-TbAlSi, τ-TbAlSi and τ-TbAlSi have been confirmed, while the compound τ (TbAlSi, crystal structure oI10-WCoB) was not previously known in the literature for the Tb-Al-Si system, but its formation was known in other R-Al-Si (R: Dy,Ho,Er,Tm) systems. The two ternary phases τ-TbAlSi and τ-TbAlSi show a homogeneity range, at constant Tb content. A number of boundary binary phases dissolve the third element, at 500 °C, forming ternary solid solutions extending into the ternary field: Tb(AlSi) (0 ≤ x ≤ 0.13), Tb(AlSi) (0 ≤ x ≤ 0.02), Tb(AlSi) (0 ≤ x ≤ 0.08), Tb(AlSi) (0 ≤ x ≤ 0.10), Tb(AlSi) (0 ≤ x ≤ 0.10), Tb(AlSi) (0 ≤ x ≤ 0.24) and Tb(AlSi) (0 ≤ x ≤ 0.15). The Al and Si richest part of the system is characterized by the coexistence of three phases (Al), (Si) and TbAlSi (τ); this behavior is common to all the known R-Al-Si phase diagrams. The phases are involved in the ternary eutectic equilibrium L ⇄ (Al) + (Si) + TbAlSi close to the binary eutectic point of the Al-Si binary system. Experimental measurements confirm the ternary eutectic reaction at a temperature of 565 °C. [ABSTRACT FROM AUTHOR]

It has been found that the kinetics of heating has an essential effect on copper films dispersion temperature. Annealing of nonequilibrium defects slightly slow down the diffusion processes in comparison with unannealed samples and it naturally increases the temperature of de-wetting of continuous films. It has been shown that the formation of liquid lead in continuous Cu-Pb polycrystalline films accelerates their thermal dispersion compared to the copper films of the same thickness. Minimum concentration of lead that can stimulate de-wetting of polycrystalline copper films of 50 nm thickness, is 3 wt %. Structural studies using electron and X-ray diffraction have shown that Cu and Cu-Pb films annealing and dispersing do not result in new phases and crystalline modifications. Only a slight increase in the solubility of the given system in comparison with bulk samples was found. The activation energy of de-wetting processes in Cu and Cu-Pb films, (which is equal to 1.6 and 0.2 eV respectively) has been determined by means of electron microscopic studies of kinetics of through pores growth. This process may be considered as the liquid phase mass transfer not the diffusive one due to the low activation energy of de-wetting for the films containing lead. [ABSTRACT FROM AUTHOR]

The paper analyzes the effect of severe plastic deformation on the structure, mechanical and thermal properties as well as crystallization process of a Zr 62.5 Сu 22.5 Al 10 Fe 5 alloy. High pressure torsion (HPT) induces local atomic changes and accumulates the formation of inhomogeneous chemical regions. The mechanically treated alloy structure is generally complex. The residual glassy matrix contains nanocrystalline particles. The structural changes observed during the HPT process lead to significant changes in the crystallization process. The effect of shear strain on crystallization of the Zr 62.5 Сu 22.5 Al 10 Fe 5 alloy and its properties was studied in detail using transmission electron microscopy (TEM), X-Ray diffraction (XRD), and differential scanning calorimetry (DSC) methods. • HPT leads to the formation of an inhomogeneous amorphous structure. • High strain radically changes the process of thermal solidification of the alloy. • Inhomogeneous amorphous structure is the reason for the high increase in hardness. [ABSTRACT FROM AUTHOR]

The hydrates [Na2(H2O)3(Htba)2] (1) and [Na2(H2O)4(Htba)2] (2), where H2tba is 2-thiobarbituric acid, were obtained under different thermal conditions from aqueous solutions and were structurally characterized. The molecular and supramolecular structures were compared to the known structure of [Na2(H2O)5(Htba)2] (3). In polymeric1–3, the Htba−ions are linked to Na+through O and S forming octahedra. The decrease of the number of coordination water molecules led to an increase of the total number of bridge ligands (μ2-H2O, Htba−) and a change of the Htba−coordination. These factors induced higher distortion of the octahedra. It was assumed that hydrates, with a different number of coordinated water molecules, are more probable when the central metal has weaker bonds with O water molecules and with other ligands. The net topologies of1–3were compared. Thermal decomposition and IR spectra were analyzed for1and2. [ABSTRACT FROM PUBLISHER]

Two new d -element compounds, [Co(H 2 O) 6 ](Detba) 2 ·2H 2 O ( 1 ) and [Ni(H 2 O) 6 ](Detba) 2 ·2H 2 O ( 2 ) (HDetba – 1,3-diethyl-2-thiobarbituric acid) were synthesized and characterized by single-crystal and powder X-ray diffraction analysis, TG–DSC and FT-IR. Structural analysis revealed that ( 1 ) and ( 2 ) are discrete structures, in which M 2+ ion (M = Co, Ni) is six-coordinated by water molecules and it forms an octahedron. The outer-sphere Detba − ions and H 2 O molecules participate in O H⋯(O/S) intermolecular hydrogen bonds which form the 2D layer. Thermal decomposition includes the stage of dehydration and the following stage of oxidation of Detba − with a release of CO 2 , SO 2 , H 2 O, NH 3 and isocyanate gases. [ABSTRACT FROM AUTHOR]

A novel organic crystal was prepared from l -lysine (Lly) and p-toluenesulfonic acid (pTS), which was grown from an aqueous solution by slow cooling method. The crystal system and the lattice parameters have been confirmed by single crystal X-ray diffraction studies. The FT-IR, FT-Raman, 1 H-NMR and 13 C-NMR spectral of the crystal have been recorded and analyzed. The spectral analyses confirmed the presence of various functional groups and the molecular configurations in LLTS crystal. The UV-Vis-NIR transmittance spectrum has been carried out which shows the cutoff wavelength around 280 nm. The thermal properties of crystal have been evaluated from thermogravimetric (TG) and differential thermal analysis (DTA). The melting point of grown crystal is fairly high, at around 259 °C. The nonlinear optical (NLO) properties of LLTS crystal were demonstrated by powder SHG experiment and also by quantum chemical calculations. The powder SHG efficiency of LLTS crystal is relatively low and very different from theoretical calculation results. [ABSTRACT FROM AUTHOR]

In this study, the adsorption of methane (CH) on zeolite from Sivas-Yavu region of Turkey and on forms treated with 1 M heavy metal nitrate solutions (AgYZ, Cu YZ and FeYZ) and 1, 3 and 5 M HCl solutions (HYZ, 3HYZ and 5HYZ) was investigated. Adsorption isotherms of methane by zeolite minerals were obtained using volumetric apparatus at 0 and 25 °C up to 100 kPa. Natural and modified samples were characterized by X-ray fluorescence, X-ray diffraction (XRD), thermogravimetric/differential thermal analysis and nitrogen adsorption methods. Quantitative XRD analysis showed that the major components of the natural zeolite were clinoptilolite and mordenite, together with minor amounts of quartz, feldspar and clay mineral. Among all the modified forms, Fe-form of zeolite sample exhibited the highest adsorption capacity for CH at both temperatures. The adsorption capacity of CH on FeYZ increased from 0.597 to 0.796 mmol g as the temperature decreased from 25 to 0 °C. In addition, uptake of CH on the adsorbents decreased with increasing acid concentrations. [ABSTRACT FROM AUTHOR]

Four new compounds of 1,3-diethyl-2-thiobarbituric acid (C 8 H 11 N 2 O 2 S, Hdetba) with Rb + , Cs + , Tl + and NH 4 + ions were prepared by Hdetba neutralization with the metal carbonates or ammonium hydroxide in aqueous solution. The colorless crystals have been investigated using X-ray diffraction techniques, differential scanning calorimetry, thermogravimetry and infrared spectroscopy. The coordination compounds of MDetba with M = Rb, Cs and Tl crystallize in the orthorhombic space group P 2 1 2 1 2 1 , but compound NH 4 Detba crystallizes in the triclinic space group P 1 ¯ . The MDetba structures were compared at the molecular and supramolecular levels. The Detba − ion in the NH 4 + compound forms conformer (A) with two diethyl groups on one side of the ion ring, whereas the Detba − ion in the Rb(I), Cs(I) and Tl(I) compounds forms conformer (B) with two diethyl groups on different sides of the ring. The results of IR spectroscopy and thermal analysis are consistent with the X-ray data. [ABSTRACT FROM AUTHOR]

New mixed crystal of Yb: Y 0.78 Lu 0.22 VO 4 with Yb ion concentration of 0.3 at% was grown by Czochralski method. Transmission synchrotron X-ray topography implies that this mixed crystal follows a rotational growth pattern. Crystal structure of this crystal was determined by X-ray diffraction. It showed that this crystal possesses a tetragonal zircon structure (ZrSiO 4 , space group I41/amd), as YVO 4 and LuVO 4 do. Thermal properties of this crystal were characterized by measuring its specific heat, thermal expansion coefficients and thermal conductivities. The specific heat was determined to be 0.500 J g −1 K −1 at 293 K. The average linear thermal expansion coefficients were calculated to be α 11 = 1.73 × 10 −6 K −1 and α 33 = 9.43 × 10 −6 K −1 , over the temperature range of 300–777 K. The thermal conductivities were calculated to be κ 11 = 5.47 W m −1 K −1 and κ 33 = 6.64 W m −1 K −1 at 303 K. Continuous-wave (cw) laser test on Yb: Y 0.78 Lu 0.22 VO 4 was conducted at room temperature in the wavelength range of 1035.7–1048.3 nm, and a 13.5% optical-to-optical efficiency was achieved. The good thermal properties of Yb:Y 0.78 Lu 0.22 VO 4 mixed crystal and its attractive cw laser performance make it very suitable for practical applications. [ABSTRACT FROM AUTHOR]

Binuclear [Ni 2 (en) 2 (H 2 O) 6 (pyr)]·4H 2 O complex undergoes dehydration in 325–400 K temperature region, which is accompanied by polymerization. Polymerized product is characterized by chelate coordination of carboxylate group to Ni, as identified by vibrational spectroscopy. XRD and spectroscopic measurements suggest that the resulting dehydration product is two-dimensional layered polymer with weak interconnectivity between the polymer layers. A combination of experimental measurements and DFT calculations was used to identify two reaction mechanisms, as well as the factors determining the change from one mechanism to the other. Reaction mechanism changes with increase in the heating rate, due to slow diffusion of released water inhibiting the polymerization. Polymerization occurs in parallel with dehydration at lower heating rates, while it follows dehydration at higher heating rates, leading to an increase in overall enthalpy of the reaction of around 50 kJ mol −1 and decrease in crystallinity of the polymeric product. Determined isokinetic temperature of the dehydration reaction corresponds to the vibrational frequency of Ni OH 2 bond. [ABSTRACT FROM AUTHOR]

Zofenopril calcium (ZOF) is one of the newest angiotensin-converting enzyme (ACE) inhibitors, highly lipophilic and with low water solubility. This research investigates the interaction between ZOF and a chemically modified derivative of β-cyclodextrin, 2-hydroxypropyl-β-cyclodextrin (HPBCD), in order to prove the formation of an inclusion complex with an enhanced water solubility profile of ZOF. In this research, for the first time, the physicochemical characterization and the solubility profile of an inclusion complex between ZOF and HPBCD are reported. Different spectroscopic techniques (UV absorption spectrometry, powder X-ray diffraction, attenuated total reflectance Fourier transform IR spectroscopy) were applied in order to prove the formation of the ZOF/HPBCD inclusion complex, both in water and in the solid state, backed by thermal analysis (TGA/DTG/HF). The obtained results confirmed that the physicochemical properties of the ZOF/HPBCD binary system, prepared using the kneading method, are different in comparison to both with the parent substances and the corresponding physical mixture, thus suggesting that an inclusion complex was formed. After the formation of the inclusion complex with HPBCD, the solubility test indicated that the water solubility of ZOF was increased 5-fold. [ABSTRACT FROM AUTHOR]

Good quality single crystals of benzimidazolone (CHNO) were grown by slow evaporation of a solution at room temperature. The structure of the compound was determined by single-crystal X-ray diffraction. The compound was found to crystallize in monoclinic space group P2/ n with Z = 4; the molecule is symmetrical to the mirror. The unit cell dimensions are: a = 5.20903(1) Å, b = 5.0557(1) Å, c = 23.4320(3) Å, and V = 627.26(5) Å. The bicyclic system adopts a planar conformation and an intermolecular hydrogen bond is formed between the NH group and the oxygen atom of a neighbouring molecule. Thermal analysis was used to study heat transfer through the structure and Fourier transform infrared (FTIR) and polarized Raman spectral analysis were used to confirm the presence of compound's functional groups. The experimental results were compared with those obtained theoretically by calculation, for example by use of the 3-21G* ab-initio method. [ABSTRACT FROM AUTHOR]

• A comparative analysis of Zn 1.88–2 x Mn 2 x Mg 0.12 SiO 4 and Zn 2–2 x Mn 2x SiO 4 was performed. • Lattice parameters of both solid solutions change nonmonotonically. • Melting points of solid solutions decrease with increasing manganese concentration. • The introduction of 6 at% magnesium reduces decay time by almost a factor of two. [Display omitted] The effect of magnesium introduction on the structural, thermal, and luminescent characteristics of Zn 2 SiO 4 :Mn at the fixed magnesium concentration of 6 at% has been studied. Zn 1.88–2 x Mn 2 x Mg 0.12 SiO 4 phosphors were synthesized by the solid phase method. The structural properties were studied using X-ray diffraction. The luminescent properties were characterized by the PLE and PL spectra. The charge state of manganese ions was determined by the XPS method. It was found that the Zn 1.88–2 x Mn 2 x Mg 0.12 SiO 4 samples at x ≤ 0.14 were single-phase. The unit cell parameters of the solid solutions changed nonmonotonically with increasing x. The change in the linear trend of the parameters occurred at x = 0.06, and was caused by the oxidation of a part of the Mn2+ ions to Mn3+. The introduction of 6 at% magnesium into the Zn 2–2x Mn 2x SiO 4 structure caused an inversion of the crystallographic positions in which manganese was predominantly oxidized. It was shown that the melting temperatures of the Zn 2–2x Mn 2x SiO 4 and Zn 1.88–2 x Mn 2 x Mg 0.12 SiO 4 solid solutions decreased with increasing manganese concentration, but were practically independent of the presence of magnesium. The structural phase transition α→β was recorded in the premelting region for all Zn 2–2 x Mn 2 x SiO 4 compositions. For the Zn 1.88–2 x Mn 2 x Mg 0.12 SiO 4 solid solutions, the α→β transition was registered only for x ˂0.06. The optimal photoluminescence intensity of Zn 2–2 x Mn 2 x SiO 4 shifted to the region of lower values of x with the introduction of magnesium and turned out to be maximum for Zn 1.76 Mn 0.12 Mg 0.12 SiO 4. The introduction of 6 at% magnesium reduced the decay time by almost a factor of two; for the sample with x = 0.06 the decay time was 0.654 ms. [ABSTRACT FROM AUTHOR]

Mono-phase high critical temperature (Bi,Pb)-2223 superconductor from the off-stoichiometric BiPbSrCaCuO belonging to the tetragonal system, has been obtained. We studied the crystalline structure, the stress of second order, and the texture of the surface pellet, in the framework of XRD diffractometry. Results of the thermal measurements made in the nitrogen, with a heating rate of 10 K min, from room temperature (RT) to 1273.15 K, show a slow mass decrease of 1.25 % from RT to 1003.15 K probably due to the elimination of water, oxygen, and of the other gases accumulated on the crystallite surface through chemical adsorption. Two endothermic processes were evidenced on DSC, and DTG curves: the first in the range of 1135.15-1193.15 K (melting and slow decomposition), and another after 1217.45 K (decomposition). The contribution of crystal lattice to the estimated specific heat capacity was in conformity with the Einstein model, giving for the Einstein temperature a value of 1297.5 K. In conformity with the Müller critical state model, we found linear dependences for intragrain critical transition temperature, T, and intergrain coupling temperature, T, versus the amplitude of the external AC magnetic fields. There was evidenced that intergrain critical currents are five orders smaller than the intragrain critical currents. [ABSTRACT FROM AUTHOR]

The present paper undertakes the study of a new hybrid compound [2-CH3C6H4NH3]2SeO4 characterized by the X-ray diffraction, IR, DFT calculation, TG-DTA, DSC and electrical conductivity. This new organic-inorganic hybrid compound crystallizes in the monoclinic system with P21/c space group and the following parameters a = 14.821 (5) Å; b = 16.245 (5) Å; c = 6.713 (5) Å; ß = 102.844 (5)°, Z = 4 and V = 1575.8 (14) ų. The atomic arrangement can be described as isolated tetrahedral SeO42- connected with the organic groups by means of NH⋯O hydrogen bonds to form infinite sinusoidal chains in the c-direction. BHHLYP/6-311g** method was used to determine the harmonic frequencies for two optimized cluster structures. The calculated modes were animated using the Molden graphical package to give tentative assignments of the observed IR spectra. Thermal analysis of the title compound does not indicate the occurrence of a phase transition in the temperature range of 300-650 K. Dielectric study of this compound has been measured, in order to determine the conductivity. The conductivity relaxation parameters associated with some H+ conduction have been determined from an analysis of the M"/M"max spectrum measured in a wide temperature range. [ABSTRACT FROM AUTHOR]

Nanometric carbides of transition metals and silicon are obtained by using precursors. Control of the course of these processes require data concerning transformations of single precursor, transformations of precursor in the presence of reducing agent and synthesis of the carbide. In this work, the way of investigating such processes is described on the example of thermal decomposition of (NH)MoO·4HO (precursor) in argon. The measurements were carried out by TG-DSC method. The solid products were identified by XRD method, and the gaseous products were determined by mass spectrometry method. There was demonstrated that the investigated process proceeded in five stages. Kinetic models (forms of f( α) and g( α) function) most consistent with experimental data and coefficients of Arrhenius equation A and E were determined for the stages. The Kissinger method and the Coats-Redfern equation were applied. In case of the Coats-Redfern equation, the calculations were performed by analogue method. In this way good consistency between the calculated and determined conversion degrees α( T) at practically constant values of A and E were obtained for distinguished stages and different sample heating rates. [ABSTRACT FROM AUTHOR]

A novel cadmium cyclohexaphosphate (C5H14N2)2Cd2Cl2P6O18.4H2O has been prepared and characterized by single-crystal X-ray diffraction, infrared and Raman spectroscopies, thermogravimetric analysis, and cyclic voltammetry. The structure consists of vertex linked of CdO5Cl octahedral and P6O18rings assembled into a two-dimensional macroanionic layers. Organic double-protonated homopiperazine cations are located between these layers and interact with the framework both electrostatically and via hydrogen bonds of N–H···O(Cl). [Supplemental materials are available for this article. Go to the publisher's onlineedition ofPhosphorus, Sulfur, and Silicon and the Related Elementsto view the following free supplemental files: Additional figures] [ABSTRACT FROM PUBLISHER]

This study focuses on the thermal and mineralogical transformations of clay ceramic pastes. The pastes contain different amounts of sugarcane bagasse ash waste. Thermal and mineralogical changes occurring during firing were characterized by differential thermal analysis, thermogravimetry analysis (TG), X-ray diffraction (XRD), and scanning electron microscopy. On heating three endothermic events within the 73.5-75.7, 276.9-283.5, and 567.1-573.5 °C temperature ranges were identified. The endothermic valleys could be mainly interpreted as the release of physically adsorbed water, dehydration of hydroxides, and dehydroxylation of kaolinite, respectively. Two exothermic events within the 618.9-690.1 and 948 °C temperature ranges were identified. The exothermic peaks are associated with the decomposition of organic compounds and crystallization of mullite from metakaolinite, respectively. TG results indicate that the clay ceramic pastes had a total mass loss in the 13.1-13.6 % range, and are dependent on the sugarcane bagasse ash waste amount added. It was found that the replacement of natural clay with sugarcane bagasse ash waste, in the range up to 20 wt%, influenced the thermal behavior and technological properties of the clay ceramic pastes. In addition, the thermal analysis results agree well with the XRD. [ABSTRACT FROM AUTHOR]

Highlight: [•] Systematic studies have resulted in the growth of high quality nonlinear optical material. [•] The grown crystal has high laser damage threshold and the NLO efficiency is 1.6 times greater than that of KDP. [•] The grown crystals were characterized and reported for the first time. [•] The results suggest that LPB could be expected to be a suitable material for the NLO device fabrication. [ABSTRACT FROM AUTHOR]

Nanocomposites based on an organically modified bentonite, from Maghnia Algeria (OBT) and a copolymer of methyl methacrylate with 4-vinylpyridine (PMM4VP) synthesized in dioxan at room temperature using a neutral Ni(II)α-benzoinoxime complex as a single component initiator, were elaborated via solution intercalation method and characterized by several techniques. X-ray diffraction and transmission electron microscopy investigations indicate that mainly exfoliated and intercalated PMM4VP/OBT nanocomposites were elaborated and that the degree of exfoliation decreases with an increase of the OBT loading. Thermal analyses of these nanocomposites compared with their virgin copolymer confirmed a significant improvement of their thermal stability as evidenced by an increase of 28°C in their onset degradation temperatures. In addition, differential scanning calorimetry displayed an increase in the range of 12-18°C in their glass transition temperatures relative to their virgin copolymer. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

The isothermal and non-isothermal decompositions of cellulose nanofiber (CNF) and microfibrillated cellulose (MFC)-filled polypropylene (PP) composites were evaluated and compared with microcrystalline cellulose (MCC)-filled composites by means of thermogravimetric analysis (TG). X-ray diffraction was employed to evaluate crystallinity of the composites. The degree of maximum thermal degradation (ultimate DTG peak value) increased and thermal degradation onset temperature decreased as the cellulose content increased because the thermal stability of cellulose fillers is lower than that of neat PP, but the thermal degradation of the composite was hindered at higher temperature conditions because of the increased residual mass content of the cellulose nanofibril fillers compared to the matrix polymer. The isothermal residual mass of the cellulose nanofibril-filled PP composites under melt blending and injection molding temperatures was decreased marginally by incorporation of the cellulose reinforcement but still exhibited considerable isothermal stability. The raw materials and composites examined in this study were not affected by the manufacturing process temperatures utilized to produce the composites. The MCC decreased the composite crystallinity while the nano-sized cellulose (CNF and MFC) did not appear to have an effect on crystallinity. [ABSTRACT FROM AUTHOR]

The aim of this article is to propose advances for the preparation of hybrid nanocomposites prepared by the combination of intercalation from solution and melt-processing methods. This research investigates the effect of the laponite RDS content on the thermal, structural, and mechanical properties of thermoplastic starch (TPS). X-ray diffraction was performed to investigate the dispersion of the laponite RDS layers into the TPS matrix. The results show good nanodispersion, intercalation, and exfoliation of the clay platelets, indicating that these composites are true nanocomposites. The presence of laponite RDS also improves the thermal stability and mechanical properties of the TPSmatrix due to its reinforcement effect which was optimized by the high degree of exfoliation of the clay. Thus, these results indicate that the exfoliated TPS–laponite nanocomposites have great potential for industrial applications and, more specifically, in the packaging field. [ABSTRACT FROM AUTHOR]

Abstract: Six new transition metal(III) phosphites A I[VIII(HPO3)2], where A=K (1), NH4 (2) and Rb (3) and A I[FeIII(HPO3)2] where A=K (4), NH4 (5) and Rb (6) have been synthesized under hydrothermal conditions and the solid-state structures were solved from single-crystal X-ray diffraction data. These compounds crystallize in the hexagonal system, space group P63 mc (no. 186), with a=5.3294(2)Å and c=12.3130(5)Å for 1, a=5.3330(2)Å and c=12.8760(4)Å for 2, a=5.3459(2)Å and c=12.6850(8)Å for 3, a=5.3256(1)Å and c=12.2362(3)Å for 4, a=5.3229(2)Å and c=12.8562(4)Å for 5, a=5.3393(2)Å and c=12.6913(5)Å for 6, with Z=2 in the six phases. The crystal structures of these compounds are isotypic and exhibit a layered structure stacked along the c-axis with the A + cations located in the interlayer space. The [M III(HPO3)2]− sheets are formed by MO6 octahedra interconnected by HPO3 tetrahedral phosphite oxoanions through sharing vertices. Thermal analysis shows a large range of stability for compounds containing potassium and rubidium cations with decomposition starting around 550K for stable compounds and above 840K for the most stable compounds leading in general to pyrophosphate compounds. Triangular nets of metallic centers are observed within the layers in which antiferromagnetic interactions are evidenced by magnetic susceptibility measurements suggesting magnetic frustration. [Copyright &y& Elsevier]

Abstract: The framework flexibility of the nanosized rhombohedrally distorted titanosilicate analog of the mineral pharmacosiderite (RTS) has been in situ studied by powder X-ray diffraction at elevated temperatures. Between 30 and 175°C the rhombohedral lattice showed tendency to shrink and open the angle of the axes. At 125°C the cell distortion resulted in pseudo cubic cell metrics where the reflections (021), (01−2), (211), (220), (301) and (311) have been reduced. After heating at 175°C the recovery of the reduced reflections has not been completed and the lattice remained shrank at room temperature. [Copyright &y& Elsevier]

Novel type of highly swollen beads were prepared by grafting 2-hydroxyethylacrylate onto biodegradable Sodium alginate (SA) via free-radical polymerization using potassium persulphate as an initiator and Triprolidine hydrochloride as a model drug. Evidence of grafting was obtained by fourier transform infrared spectroscopic technique. Morphological properties of the beads were studied by SEM analysis. Thermal properties and crystallinity of the beads were characterized using differential scanning calorimetry and thermogravimetric analysis and X-ray diffraction techniques, respectively. Dissolution experiments were performed to study the release profiles at 37 °C in phosphate buffer solution (pH-7.4). Effect of monomer content, crosslinking agent and drug/polymer ratio on swelling properties and release profiles were also comparatively studied. A dissolution result concludes that drug release decreases with increasing crosslinker content. The highest release (96%) was obtained for the beads prepared with 0.5 mL crosslinking agent. Equilibrium swelling degree also supports the drug release profiles confirming SA-g-HEA beads showed better release profiles compare to plain SA beads. [ABSTRACT FROM AUTHOR]

Abstract: Single crystals of novel semi-organic novel nonlinear optical material bis L-glutamine sodium nitrate (BGSN) were grown by slow evaporation technique. Single crystal XRD revealed that material crystallized in orthorhombic crystal system with non-centrosymmetric space group P212121. Molecular mass of BGSN has been measured by using mass spectroscopic analysis. Surface morphology of the grown crystal was studied by scanning electron microscopy (SEM). The presence of sodium in the compound and composition of grown crystals was confirmed on the basis of energy dispersive analysis of X-ray (EDAX). Photoluminescence study was carried out using a Xe-lamp source in the range of 250–450nm. The thermal stability of the crystal is investigated using thermo-gravimetric analysis studies. Second harmonic generation (SHG) efficiency of the grown crystal was measured by Kurtz powder method. [Copyright &y& Elsevier]

Abstract: Phase equilibria and glass formation studies of the (1− x)TeO2–xCdO system (0.05≤ x ≤0.33mol) were realized by using differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The samples were prepared by applying a conventional melt-quenching technique at 800°C. The glass formation range of the system was determined as 0.05≤ x <0.15 and the sample containing 10mol% CdO showed the highest glass stability. Crystallization behavior of the TeO2–CdO glasses was investigated and formation and/or transformation of different phases were detected for each crystallization reaction. In order to obtain thermal stability of the system, as-cast samples were heat-treated above all crystallization reaction temperatures at 550°C for 24h. A binary eutectic: liquid→TeO2 +CdTe2O5 was detected at 638±4°C. Crystallization behavior of the TeO2–CdO glasses and microstructural characterization of the TeO2–CdTe2O5 system was realized. [Copyright &y& Elsevier]

Heterobimetallic oxalato complex precursors, manganese(II)tetraaquatris(oxalato)lanthanate(III)hexahydrate (MnOLa), cobalt(II)pentaaquatris(oxalato)lanthanate(III)trihydrate (CoOLa), nickel(II)pentaaquatris(oxalato)lanthanate(III)hexahydrate (NiOLa) and copper(II)diaaquatris(oxalato)lanthanate(III)monohydrate (CuOLa) of the type, M[La(CO)(HO)]· nHO have been synthesized in aqueous medium. The precursors were characterized by elemental analysis, IR, electronic spectral and powder X-ray diffraction studies. The good crystalline nature with monoclinic structures predominates in MnOLa and NiOLa whereas triclinic structures were found in CoOLa and CuOLa. The solid-state thermal behaviour of the precursors was explored using TG, DTG and DTA in air. The MnOLa generated a mixture species consisting mainly of MnO, MnO, MnO, LaO and LaMnO at 1000 °C through the formation of several intermediate species at 380 and 570 °C. The studies revealed that CoOLa led mainly to LaCoO and LaCoO along with some oxides of both the cobalt and lanthanum at 1000 °C. In case of nickel analogue the mixture species identified at 1000 °C are mainly of LaNiO, LaO, NiO and NiO In case of CuOLa the product at 1000 °C consisted of LaCuO, LaCuO and oxides of copper and lanthanum. The nature of decomposition of the precursors in nitrogen were seen from DSC study and the kinetic parameters i.e., E, ln k, Δ H, Δ S and order of reaction of all the steps were evaluated and discussed. [ABSTRACT FROM AUTHOR]

Hematite with different particle sizes was obtained through isothermal annealing and mechanochemical ball-milling methods. The hematite phase is very stable under air atmosphere. The thermal stabilities of hematite under argon atmosphere were characterized by thermal analysis studies up to 800 °C using a simultaneous DSC-TG technique. The lattice parameters a and c of hematite with different particle sizes were extracted from the Rietveld structural refinement of powder X-ray diffraction patterns. Decomposition of hematite into a lower oxidation state in inert argon atmosphere was studied by the TG experiments for the first time and the enthalpy associated with the decomposition reaction was determined from the DSC studies. Particle size has a strong effect on the thermal behavior of hematite samples. Ball-milled hematite samples with smaller particle size showed that the phase transformation was extended to higher temperature range with larger enthalpy. Hematite with larger average particle size showed higher stability under argon atmosphere. [ABSTRACT FROM AUTHOR]

In this study, we have studied the stability of TiO-CdSe nanocomposites in which the individual moieties are linked using a bifunctional linker (mercaptopropionic acid). Nanoparticles of TiO and CdSe are synthesized by sol-gel and one pot methods. The equimolar amount of the above particles is utilized to prepare nanocomposites with and without linker. These samples are characterized for their structural, thermal, and optical properties using X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetric analysis (TG), Fourier transform infra-red spectroscopy (FTIR), and UV-Vis spectroscopy. The average particle size of TiO and CdSe are 16 and 23 nm, respectively. The addition of a bifunctional linker shows remarkable effect on the properties of TiO-CdSe nanocomposites. [ABSTRACT FROM AUTHOR]

Abstract: Good transparent single crystals of l-phenylalanine l-phenylalaninium malonate (LPPMA) have been grown successfully by slow evaporation technique from aqueous solution. Single crystal X-ray diffractometer was utilized to measure unit cell parameter and to confirm the crystal structure. The chemical structure of compound was established by FT-NMR technique. The vibrational modes of the molecules of elucidated from FTIR spectra. Its optical behaviour has been examined by UV–vis spectral analysis, which shows the absence of absorbance in the visible region. Thermal properties of the LPPMA crystal were carried out by thermo gravimetric analysis (TGA) and differential thermal analysis (DTA) techniques, which indicate that the material does not decompose before melting. The melting point of grown crystal was observed as 180°C by melting point apparatus. The NLO property was confirmed by the powder technique of Kurtz and Perry. The dielectric behaviour of the sample was also studied for the first time. [Copyright &y& Elsevier]

The consistent interest in supporting research and development of magnetic materials during the last century is revealed in their steadily increasing market. In this work, the soft magnetic nanocrystalline FINEMET alloy was prepared with commercial purity raw materials and compared for the first time with the generally studied high purity one. The exhaustive characterization covers several diverse techniques: X-ray diffraction, Mössbauer spectroscopy, differential scanning calorimetry, differential thermal analysis and magnetic properties. In addition, a brief economic analysis is presented. For the alloys annealed at 813 K, the value of the grain size was 16 nm with 19·5% of Si, the coercivity was 0·30 A m while the saturation was 1·2 T. These results prove that structural, magnetic and thermal properties of this material are very close to the expensive high purity FINEMET alloy, while a cost reduction of almost 98% seems highly attractive for laboratories and industry. The analysis should be useful not only for the production of FINEMETs, but for other type of systems with similar constitutive elements as well, including soft and hard magnetic materials. [ABSTRACT FROM AUTHOR]

Blends of Poly(ethylene terephthalate), (PET), and poly(ethylene naphthalene 2,6-dicarboxylate), (PEN), were prepared in a twin-screw extruder. Samples were investigated by differential scanning calorimetry (DSC) and proton nuclear magnetic resonance (H NMR) measurements to evaluate the extent of transesterification reaction. X-ray diffraction (XRD) test was performed to examine the effect of transesterification reactions on crystalline structure of the blends. Thermogravimetry analysis (TGA) was used to study thermal decomposition of the blends which could be explained by the level of transesterification reaction for various blend compositions. The kinetic of the decomposition reaction was analyzed by Freeman-Carroll and Chang models. It was found that these two methods were acceptable models for describing the thermal decomposition of the blends however, the Chang model showed better correlation with the experimental data as compared to the other model. Results revealed that progress of transesterification reaction in blends depends on temperature and mixing time, which have dominant role in thermal behavior and decomposition kinetic of the blends. Effect of nanoclay on transesterification reactions and degradation behavior was also investigated. It was found that the nanoclay inhibited the transesterification reactions and reduced the thermal stability of the blends. PET degraded much faster than PEN in O environment while, an opposite trend was observed in N atmosphere. [ABSTRACT FROM AUTHOR]

Thermal properties and crystallization of glasses from PbO-MoO-PO ternary system were studied in three compositional series (100 − x)[0.5PbO-0.5PO]- xMoO (A), 50PbO- yMoO-(50 − y)PO (B), and (50 − z)PbO- zMoO-50PO (C). Glass transition temperature, crystallization temperature, coefficient of thermal expansion, and dilatation softening temperature of the studied glasses were determined by differential thermal analysis and dilatometry. Crystallization products of annealed glass samples were investigated by X-ray diffraction and Raman spectroscopy. X-ray diffraction analysis of crystallized glasses revealed the formation of PbPO, PbPO, and PbMoO in the samples of the B series. In the series A and C in the samples with a high MoO content, crystalline compounds of Pb(MoO)(PO) and (MoO)(PO), respectively, were identified. Raman spectra of crystalline samples confirmed the results of X-ray diffraction measurements and provided also information on thermal stability of glasses and formation of glass-crystalline phases in the studied glass series. [ABSTRACT FROM AUTHOR]

The crystal structure of a double complex salt of the composition [Au(en)][Cu(CO)]·8HO (en = ethylenediamine) at 150 K is determined by single crystal X-ray diffraction. The crystal data for CHAuCuNO are: a = 9.1761(3) Å, b = 16.9749(6) Å, c = 13.4475(5) Å, β = 104.333(1)°, V = 2029.43(12) Å, P2/ c space group, Z = 2, d = 2.450 g/cm. It is demonstrated that the thermal decomposition of the double complex salt in a helium or hydrogen atmosphere affords the solid solution AuCu. [ABSTRACT FROM AUTHOR]

Abstract: Organic modification of starch nanoparticles was carried out at room temperature to obtain nanosized hydrophobic derivatives. The particle size of the modified starch nanoparticles obtained by transmission electron microscopy (TEM) and X-ray diffraction (XRD) was found out to be around 50nm. The hydrophobic starch derivatives were used to prepare bionanocomposites of natural rubber by mastication process. The properties were compared with composites obtained from untreated starch nanoparticles and carbon black. Up to 30phr of the fillers were successfully incorporated leading to an enhancement in mechanical as well as thermal properties. Scanning electron microscopy (SEM) revealed single phase morphology of nanobiocomposites indicating compatibility of the filler and matrix. Dynamic mechanical properties were seen as a broad tan delta peak over a large range of temperature. It was observed that modified starch nanoparticles could be a potential substitute for carbon black as reinforcing agents and as promising materials for vibration damping applications. [Copyright &y& Elsevier]

Abstract: Reactions of 25,26,27,28-tetrahydroxy-calix[4]arene (1) with 4 equiv. of m-carboxybenzenediazonium chloride in the presence of NaOAc∙3H2O in DMF produced a new azo calix[4]arene [H4L] (2) (H4L=5,11,17,23-tetrakis[(m-carboxyphenyl)azo]-25,26,27,28-tetrahydroxycalix[4]arene) in 96% yield. Hydrothermal reactions of Cd(NO3)2·4H2O with H4L at 90°C under pH=5.0–6.0 gave rise to a coordination polymer {[H3O]2[Cd7L4(DMF)4(EtOH)2(H2O)2]·5DMF·11.5EtOH·H2O}n (3). Compound 3 was characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Compound 3 consists of a 3D framework with an unprecedented (3346526371)(364135861) topology. The thermal properties of 2 and 3 were also investigated. [Copyright &y& Elsevier]

Abstract: Multinary Ti–Al–N thin films are used for various applications where hard, wear and oxidation resistant materials are needed. Here, we study the effect of Zr addition on structure, mechanical and thermal properties of Ti1-xAlxN based coatings under the guidance of ab initio calculations. The preparation of Ti1-x-zAlxZrzN by magnetron sputtering verifies the suggested cubic (NaCl-type) structure for x below 0.6–0.7 and z≤0.4. Increasing the Zr content from z=0 to 0.17, while keeping x at ~0.5, results in a hardness increase from ~33 to 37GPa, and a lattice parameter increase from 4.18 to 4.29Å. The latter are in excellent agreement with ab initio data. Alloying with Zr also promotes the formation of cubic domains but retards the formation of stable wurtzite AlN during thermal annealing. This leads to high hardness values of ~40GPa over a broad temperature range of 700–1100°C for Ti0.40Al0.55Zr0.05N. Furthermore, Zr assists the formation of a dense oxide scale. After 20h exposure in air at 950°C, where Ti0.48Al0.52N is already completely oxidized, only a ~1μm thin oxide scale is formed on top of the otherwise still intact ~2.5μm thin film Ti0.40Al0.55Zr0.05N. [Copyright &y& Elsevier]

Polycrystalline garnet ferrites Dy3-xNix Fe5O12, where (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) have been prepared by the standard ceramic technique and their crystalline structure were identified by X-ray diffraction and IR spectroscopy. The differential thermal analysis (DTA) reveals two peaks. It is observed that an endothermic peak between 587 and 498 K for all samples which is due to the magnetic phase change from ferrimagnetic to paramagnetic state. The exothermic peak at about 700 K may be attributed to the crystallization of Dy3-x NixFe5O12 with garnet structure. DC electrical resistivity, thermoelectric power, charge carrier concentration and charge carrier mobility have been studied at different temperatures: It was found that the DC electrical conductivity increases linearly with increasing temperature ensuring the semiconducting nature of samples. The values of the thermoelectric power were negative for samples of 0.0 < x < 0.4 indicating that the majority of the charge carrier are electrons in these samples while it was positive for sample of x = 0.5 at room temperature, and negative at high temperature. Using the values of the DC electrical conductivity and thermoelectric power, the values of the charge carrier concentration and the charge carrier mobility were calculated. Finally thermal properties have been studied. [ABSTRACT FROM AUTHOR]

This article studied the thermal behavior and the evolution of the crystalline phases with temperature of the red mud (bauxite tailing) from an aluminum industry at Maranhão, North-Northwestern Brazil. The experiments were carried out by Field Emission Scanning Electron Microscopy (FE-SEM), Simultaneous Thermal Analysis (TG-DSC), Optical Dilatometry up to 1623 K, and X-ray diffraction (XRD) of previously heated samples between 523 and 1523 K. The crystalline phases and the amorphous contents were quantified on raw and heated samples (at 1523 K) according to the Rietveld Quantitative Analysis (RQA) method. The data obtained showed that the raw red mud is composed by a mixture of seven different phases (hematite, goethite, sodalite, anatase, gibbsite, calcite, and amorphous). Finally in the interval of 1023-1523 K the following crystalline phases: hematite, nepheline, sodalite, anatase, perovskite, and pseudobrookite have been observed. [ABSTRACT FROM AUTHOR]