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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]

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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]

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]

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]

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.

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]

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]

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]

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]

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]

• 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]

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]

Five new compounds were synthesized by a solvent-free hydrothermal synthesis approach, based on cobalt and iron sulfates and o-, m- or p-phenylenediamine. Their crystal structures were determined by XRPD methods. The compounds were studied by SEM EDX, TG and temperature-dependent XRPD techniques. [Display omitted] Five new compounds were synthesized by a solvent-free synthesis approach, based on cobalt and iron sulfates and 1,2-phenylenediamine (OPD), 1,3-phenylenediamine (MPD) and 1,4-phenylenediamine (PPD) as organic templates and linkers. Their dimensionalities and formulas are: 1D: Fe(OPD) 2 SO 4 (1); 2D: Fe(MPD) 2 SO 4 (2), Co(MPD) 2 SO 4 (3); 3D: Fe(PPD)SO 4 (4) and Co(PPD)SO 4 (5). The crystal structures were determined using data from X-ray powder diffraction measurements (XRPD). The purity and morphology of the compounds were studied by elemental analyses and SEM EDX investigations and their thermal stability was determined by thermogravimetric (TG) and temperature-dependent XRPD techniques. [ABSTRACT FROM AUTHOR]

A method for the synthesis of the Mo(acac) complex is proposed and its crystal structure is determined by single crystal X-ray diffraction. Space group P2/ c, a = 19.7538(5) Å, b = 7.4821(2) Å, c = 34.6190(8) Å, β = 96.8055(12)°, V = 5080.6(2) Å, Z = 12. The compound is studied by the thermogravimetric analysis, and MoO is shown to be the result of its decomposition. [ABSTRACT FROM AUTHOR]

• Two Strandberg type phosphomolybdates anions with different organic counterions are synthetized. • As the non-protonated anion is more prone to be reduced, we show through the analysis of the two compounds and the literature that the selection of the precursors may be crucial for the stabilization of the suitable anion. • Thermal and electrochemical properties were also investigated. Strandberg-type phosphomolybdate anions are metal-oxide clusters with general formula [H n P 2 Mo 5 O 23 ](6−n)− (n = 0, 1, 2). The protonation/deprotonation of this anion affects its redox properties. Herein, we explain how to select the organic counterions to direct the synthesis towards the non-protonated or protonated anion. The method is illustrated with the synthesis of two new compounds (C 5 H 16 N 2) 3 [P 2 Mo 5 O 23 ]·4H 2 O (1) and (CH 6 N) 4 [H 2 P 2 Mo 5 O 23 ].CH 5 N·4H 2 O (2). The two compounds were characterized by UV–Visible absorption, IR spectroscopy and single crystal X-ray diffraction. Their thermal stabilities and redox properties were also investigated. [ABSTRACT FROM AUTHOR]

The crystal structure, microstructure and thermal properties of the BaFe 11.1 In 0.9 O 19 sample have been investigated by SEM (Scanning Electron Microscope), X-ray diffraction, Raman spectroscopy, DSC (Differential Scanning Calorimetry), TGA (Thermogravimetric Analysis) and DTG (Differential Thermogravimetric Analysis) analytical methods. SEM investigations determined that, the average size of crystallites of the BaFe 11.1 In 0.9 O 19 sample is d ¯ = 5 μm. The X-ray diffraction investigations showed that, the structure of the sample corresponds to the hexagonal symmetry with P6 3 /mmc space group. An analysis of raman spectra at high temperatures determined that, there is no phase transition in the temperature range T = 20–450 °C. The lower boundary value is T ≥ 100 °C for starting thermal flux, the oxidation on mass kinetics and decomposition effects were determined from thermal analysis of the BaFe 11.1 In 0.9 O 19 sample. [ABSTRACT FROM AUTHOR]

This manuscript describes the synthesis, characterization and thermal properties of the two vanillin derivatives containing a long alkyl chain. Two vanillin derivatives 4-(heptyloxy)-3-methoxybenzaldehyde (L1) and 4-(decyloxy)-3-methoxybenzaldehyde (L2) were obtained from the reaction of the vanillin with 1-bromoheptane or 1-bromodecane in DMF reaction media, respectively. The vanillin derivatives L1 and L2 have been characterized by the 1H–13C NMR, FTIR and mass spectral techniques. Single crystals suitable for X-ray diffraction studies were grown by recrystallization of a chloroform solutions of the compounds. There are phenyl-phenyl stacking (edge to edge) interactions within the structures. Thermal analysis data (DSC) revealed that compounds do not show any liquid crystalline character. The electrochemical behaviours of the organic compounds L1 and L2 were investigated and all redox processes in the 100–1000 mV/s scan rates are irreversible. Image 1 • Two vanillin derivatives 4-(heptyloxy)-3-methoxybenzaldehyde and 4-(decyloxy)-3-methoxybenzaldehyde were prepared. • The structure of the compounds were determined by X-ray diffraction studies. • The compounds showed redox irreversible processes in the 100–1000 mV/s scan rates. • Thermal behaviours of the compounds were investigated. [ABSTRACT FROM AUTHOR]