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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]

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]

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.

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 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]

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]

• 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]

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]

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]

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]

Abstract: To study the thermal stability of polymer derived SiBNC ceramics, a polyborosilazane was pyrolyzed in N2 and NH3/N2 atmosphere, respectively. The as-pyrolyzed products were annealed in N2 atmosphere at 1200–1850°C for 2h. The chemical composition and phase structure of the as-pyrolyzed and annealed ceramics were investigated by element analysis, XRD and FT-IR. The results show that all the ceramics exhibit excellent high temperature stability. They are fully amorphous to 1700°C, and only partial crystallization, giving a mixture of Si3N4, BN and SiC phases, is observed upon heating at 1850°C. The N2 pyrolyzed products show better stability than the NH3/N2 pyrolyzed products and have less tendency to crystalline at higher temperatures. Better retention of nitrogen at high temperatures is also observed for the N2 pyrolyzed products. [Copyright &y& Elsevier]

Abstract: The melt-spinning processes of binary Sn–10wt.% Sb and ternary Sn–10wt.% Sb–In were analyzed using X-ray diffractometer and differential thermal analysis (DTA). The results showed that supersaturated solid solution and new intermetallic compound In3Sn were produced during melt-spinning technique not found under equilibrium conditions. It is also found that a small amount of In addition significantly lowers the melting point of the Sn–10wt.% Sb alloy and reduce the crystal size to ≈60nm. Also, tin–antimony solder doped with In exhibits good mechanical properties, Vickers hardness and mechanical strength due to refined microstructure. This work was performed to study the influence of rapid solidification and indium addition on structure and properties of tin–antimony based alloys. [Copyright &y& Elsevier]

Abstract: The thermal behaviour of individual and mixed solids, with different molar ratios, of basic copper carbonate and ammonium metavanadate was reported. The pure and mixed solids were thermally treated at 300, 500, 750 and 1000°C. The thermal products at various calcination temperatures were characterized by means of thermal analyses (TG–DTG–DTA), X-ray diffraction (XRD) and electron spin resonance (ESR) techniques. The catalytic activity of all solids was measured using hydrogen peroxide decomposition at 30, 40 and 50°C. The results revealed that pure basic copper carbonate decomposed to CuO at 300°C and to Cu2O at temperature above 950°C, where as pure ammonium vanadate decomposed to (NH4)2V6O16 and NH4V4O10 as an intermediate compound at 250 and 350°C before the formation of V2O5 at 450°C. CuO enhanced the formation of V2O5 at 300°C. A series of copper vanadate phases were detected, Cu5V2O10, Cu2V2O7 and Cu3V5O4, for the mixtures 3Cu:1V, 1Cu:1V and 1Cu:3V preheated at 750°C, respectively. These phases were formed as a result of solid–solid interactions between copper and vanadium oxides. The calcination temperature and the composition of the Cu–V mixtures affect the degree of crystallinity and pattern intensities of different phases detected at treatment temperatures ranged between 300 and 1000°C. The catalytic activity of mixed CuO–V2O5 was found to be greater than that of single oxides obtained at the same calcination temperatures. This might be attributed to increase in the concentration of active sites by creation of new ion pairs. No measurable catalytic activity was observed for all solids calcined at 750 and 1000°C. This might be attributed to restriction of catalytically active constituents. [Copyright &y& Elsevier]

Abstract: Several stoichiometric ternary Ti–Al–Si and quaternary Ti–Al–Si–C alloys have been prepared by mechanical alloying of elemental powder blends. The structural and morphological evolutions in these powders are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD results have shown that the elemental powders Ti–Al–Si are progressively transformed into a nanocrystalline solid solution and amorphous phase during mechanical alloying. The results for the powder mixture of quaternary 58Ti–30Al–6Si–6C have shown that supersaturated solid solutions of Ti in nano- and submicro-scales are formed, while Ti5Si3 and TiC compounds are produced in the powder mixture of 50Ti–15Al–20Si–15C. These compositions may be used as distinct precursors for preparing in situ titanium aluminide composites. Investigations on thermal stability of 40h-milled quaternary powders have indicated that Ti5Si3 is first formed at a lower temperature followed by Al2Ti4C2 and TiC at an intermediate temperature (820°C). In the case of ternary system a stable Ti5Si3 phase is formed through a series of transitions when heated to 1200°C. All the above phases are stable at elevated temperatures. [Copyright &y& Elsevier]

Abstract: Polycrystalline Bi1− x Sb x (x =0.10, 0.12 and 0.15) semiconducting alloys were synthesized by mechanical alloying in order to achieve homogeneous thermoelectric materials with improved mechanical strength. The homogeneity of the powder samples were repeatedly checked by X-ray diffraction and scanning electron microscopy to standardize the milling conditions. The best possible homogenized material was developed with the milling conditions of BPR 30:1, ball diameter 30mm, 400rpm and milling time of 15h. The electrical resistivity, thermoelectric power and thermal conductivity were measured in the temperature range 300–500K. It was found through these experiments that the composition with x =0.12 behaved in a normal semiconducting way, whereas the other two compositions (x =0.10 and 0.15) showed degenerate semiconductor behaviour. These features have been qualitatively explained from the band structure and interband scattering mechanisms. [Copyright &y& Elsevier]

Abstract: Thermally induced intermartensitic transformation in polycrystalline Ni52.5Mn23.7Ga23.8 has been investigated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). It is found that after annealing at 500°C for 4h an intermartensitic transformation, seven-layered orthorhombic martensite (7M) → five-layered tetragonal martensite (5M), appears in polycrystalline Ni52.5Mn23.7Ga23.8 alloy quenched from 800°C, where the sequence of phase transformations is austenite phase (A) → 7M→5M during cooling and 5M→7M→A during heating. The intermartensitic transformation is an independent phase transformation, but the critical transition temperatures and the transformation temperature ranges of 7M→5M are strongly affected by the martensitic transformation. [Copyright &y& Elsevier]