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This study investigates and compares the thermal phase transition and crystallization characteristics of a commercial food grade free phytosterol blend (FP) with a stigmasterol analytical standard (SS), the FP behavior in a food model system after its addition to high oleic sunflower oil (HOSO). The properties of the FP:HOSO blends were studied by differential scanning calorimetry, solid content, crystal morphology, and X-ray diffraction (XRD) measurements. The Rietveld method (RM) was applied associated with the XRD measurements to support phase analysis and the study of crystallinity degree. The materials were also characterized by means of chemical composition, such as fatty acids and triacylglycerol profiles, for HOSO, and phytosterol profile, for FP. Regarding phase behavior and crystallinity properties, FP has very similar characteristics to SS. The thermal behavior of FP:HOSO blends has two characteristic peaks, one from FP and the other from HOSO. The similarity reported in the literature between the diffraction pattern of FP and pure phytosterols is a positive characteristic for FP. A high FP concentration resulted in high supersaturation and thus the formation of small crystals. The incorporation of HOSO reduced of the large agglomeration of FP crystals and the dispersion crystalline aggregates (spherulites) of FP crystals. The application of RM in FP:HOSO blends to quantify the crystalline and amorphous phases was successfully used. The application has provided the expected value for these phases, according to the same experimental mass ratio of the blends, thereby validating the applicability of this approach in this type of material., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The in situ polymorphic forms and thermal transitions of refined, bleached and deodorized palm oil (RBDPO), palm stearin (RBDPS) and palm kernel oil (RBDPKO) were investigated using coupled X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Results indicated that the DSC onset crystallisation temperature of RBDPO was at 22.6°C, with a single reflection at 4.2Å started to appear from 23.4 to 17.1°C, and were followed by two prominent exothermic peaks at 20.1°C and 8.5°C respectively. Further cooling to -40°C leads to the further formation of a β'polymorph. Upon heating, a of β'→βtransformation was observed between 32.1 to 40.8°C, before the sample was completely melted at 43.0°C. The crystallization onset temperature of RBDPS was 44.1°C, with the appearance of the α polymorph at the same temperature as the appearance of the first sharp DSC exothermic peak. This quickly changed from α→β´ in the range 25 to 21.7°C, along with the formation of a small β peak at -40°C. Upon heating, a small XRD peak for the β polymorph was observed between 32.2 to 36.0°C, becoming a mixture of (β´+ β) between 44.0 to 52.5°C. Only the β polymorph survived further heating to 59.8°C. For RBDPKO, the crystallization onset temperature was 11.6°C, with the formation of a single sharp exothermic peak at 6.5°C corresponding to the β' polymorphic form until the temperature reached -40°C. No transformation of the polymorphic form was observed during the melting process of RBDPKO, before being completely melted at 33.2°C. This work has demonstrated the detailed dynamics of polymorphic transformations of PKO and PS, two commercially important hardstocks used widely by industry and will contribute to a greater understanding of their crystallization and melting dynamics.

An embedded-atom method (EAM) potential for the Pd–Ba alloy system has been developed in order to forward computational research in this alloying system as there is no EAM potential available for this alloy system. The force-matching method has been implemented to develop the EAM potential first, and then, optimisation to converged density-functional theory (DFT) data sets has been done to generate the accurate and reliable potential for the Pd–Ba alloy system. Some physical, elastic and thermal properties of BaPd2 crystal have been calculated through molecular dynamics (MD) simulation using the developed EAM potential and then verified these properties with the help of DFT analysis in order to examine the performance of the potential. The presence of some even peaks of BaPd2 in virtual XRD spectra using MD simulation has been justified by DFT analysis. Slight deviations in melting points calculation at different compositions of the Pd–Ba alloy system have been observed. Higher Ba–Pd interaction using radial distribution characteristics and slower kinetics for inter-diffusion through diffusional characteristics study of BaPd2 have been reported using MD simulation with the developed EAM potential. In spite of some discrepancies due to deficiency in the potential, a closer agreement between MD and DFT analysis has been observed. [ABSTRACT FROM AUTHOR]

Summary: The present study investigates the impact of germination (72 h) on physicochemical, protein solubility, in vitro protein digestibility, antinutrient, antioxidant, and structural properties of sorghum flour. Germination resulted in a reduction of crude protein, fat, fibre, and ash. However, it significantly improved the DPPH (58.42%–69.44%), total phenolic content (1.31–3.58 mg GAE g−1), and total flavonoid content (57.66–80.16 mg QE g−1). Germination also increased in vitro protein digestibility (50.12%–75.52%) and Fe2+ chelating activity (11.18%–48.06%), while reducing antinutrients such as phytic acid (176 to 86 mg/100 g) and tannin (3.53–2.16 mg/100 g). Structural analyses (XRD and FTIR) revealed modifications in crystalline and molecular structures, while scanning electron microscopy showed disrupted starch granules in germinated flour. These findings suggest that germination enhances the functional and nutritional properties of sorghum flour, making it more suitable for various applications in food products. [ABSTRACT FROM AUTHOR]

Ternary half-Heusler (HH) alloys are under intense investigations recently towards achieving high thermoelectric (TE) figure-of-merit (ZT). Of particular interest is the ZrNiPb-based HH alloy, where an optimal value of ZT ~ 0.7 at 773 K has been achieved by co-doping Sn and Bi at Pb site. In this work, we identify an excellent ZT of 1.3 in ZrNi1+xPb0.38Sn0.6Bi0.02 (x = 0.03, at 773 K) composite alloy. This is achieved by synergistic modulation of electronic as well as thermal properties via introduction of minor phase of full-Heusler (FH) in the HH matrix through compositional tuning approach. These Ni-rich ZrNi1+xPb0.38Sn0.6Bi0.02 (0 ≤ x ≤ 0.07) alloys were synthesized via energy efficient and time-curbed techniques that involved Arc melting followed by consolidation via spark plasma sintering. These alloys were characterized by XRD and SEM, which show formation of nanocomposites comprising of HH matrix phase and FH secondary minor phases. Enhancement in ZT is mainly attributed to a synchronized increase in power factor (~42%) and ~25% decrease in its thermal conductivity. Here, TE compatibility factor (S) was also calculated for all samples. The value of |S| ~ 2.7 V−1 (at 773 K) is observed for x = 0.03, which is ~17% higher than bare HH composition (x = 0.0). The theoretically calculated TE device efficiency of best-performing sample ZrNi1.03Pb0.38Sn0.6Bi0.02 is estimated to be η ~ 13.6%. Our results imply that deliberately controlled fine tuning in compositions of HH compounds through compositional tuning approach would lead to novel off-stoichiometric HH phases with enhanced ZT value for efficient TE device fabrication. [ABSTRACT FROM AUTHOR]

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]

The melt quenching technique was used to prepare tellurite glasses with compositions 70TeO2–20BaO–10WO3 (BT:W glass), 70TeO2–20BaO–10Y2O3 (BT:Y glass), 70TeO2–20BaO–10SrO (BT:Sr glass) and 70TeO2–20BaO–10Li2O (BT:Li glass). The impact of modifying ions Ba2+, W6+, Y3+, Sr2+, and Li+ on structural, physical, thermal and mechanical properties of the prepared glasses has been explored by using XRD, DTA, and FTIR spectroscopic techniques. XRD analysis conformed that the prepared glasses are amorphous and homogeneous in nature. The FTIR spectra revealed the presence of TeO4 trigonal bipyramids, TeO3 trigonal pyramids and NBOs in the network of BT:Y, BT:Sr and BT:Li glasses. Meanwhile, the structure of BT:W glass is composed of TeO4, TeO3, WO4 and WO6 units, which are connected to each other through W–O–Te linkages. The glass transition temperature and thermal stability increased in the order BT:W glass > BT:Y glass > BT:Sr glass > BT:Li glass. These results were compared to those of binary 80TeO2–20BaO glass (BT) and pure TeO2 glass. Changes in the thermal properties have been analyzed and predicted by correlating them with the calculated molar volume, ratio of packing density to mean atomic volume, dissociation energy per unit volume, field strength of the modifying ions, average single bond strength, and elastic moduli. The R-squared values of the regression lines can be improved if the effect of all structural groups as well as the uncertainty inherent in experimental measurements are taken into account. The highest thermal stability and glass transition temperature of BT:W glass making it a good candidate for shielding material in the fields of medical, industrial, and nuclear applications. [ABSTRACT FROM AUTHOR]

It is important to utilize the raw colemanite (RC) mineral, which has abundant reserves in the world, and to reduce its particles to smaller sizes for nanotechnology. However, not only the particle size of the produced colemanite powder but also its other properties need to be elucidated. By using the Taguchi design, the RC mineral was ground in a high-energy ball mill. From signal-to-noise (S/N) ratio, the smallest average particle size was found to be 3.10 µm for the experiment E04/nano-sized amorphous colemanite (NAC) powder. The characteristics of as-received RC mineral and synthesized NAC material were investigated using laser particle size analyzer, optical microscopes, SEM–EDS, XRD, TEM, HRTEM, and TGA–DTA devices. It was found that the NAC powder was not homogeneous, a small peak within the 300–20 nm range appeared, and d90, d50, d10, and dmin values were, respectively, 14.6 µm, 3.08 µm, 232 nm, and 26 nm. In the XRD analysis, the pure colemanite, calcite, and silica minerals were determined. The crystal structure of the NAC powder almost turned amorphous, and the crystallite size of (031) peak was reduced to 7.3 nm. It was deduced that the average particle size was 8.29 nm (R2 = 0.86), and the d-spacing value was 0.307 nm. This significant finding was attributed to the mobility of balls and moreover it was interpreted with an equation. An unknown transition in TGA–DTA was referred to the calcite mineral. Finally, it is believed that the synthesized NAC material will be beneficial to engineering studies as a natural/mineral additive. [ABSTRACT FROM AUTHOR]

This study focuses on the development of a nanocomposite membrane using polyvinyl chloride and nanocellulose@titanium aluminate to effectively filter and adsorb dye from wastewater. Various analytical techniques were used such as FTIR, XRD, SEM, and TGA to characterize the synthesized adsorptive nanocomposite membrane. The thermal and electrical properties of the membrane were measured using a static system. The study investigated the effect of different adsorbent dosages, pH levels, and dye concentrations on the membrane's adsorption ability. The PVC-NC@TALCM nanocomposite membrane was found to remove 98.6% of MB dye when loaded with 5% titanium aluminate at pH 10. Kinetic and isotherm studies revealed that the adsorption of MB onto the membrane followed pseudo-second-order kinetics and Freundlich isotherms, respectively. The researchers also highlighted the economic and eco-friendly nature of the PVC-NC@TALCM nanocomposite membrane as a viable option for the removal of MB from industrial wastewater. [ABSTRACT FROM AUTHOR]

Native starch exhibits undesirable properties in the final product when used as an additive. Recently, the effects of the interaction between starch and hydrocolloids on the techno‐functional properties of starch have been studied. However, this interaction has not yet been applied to a real food system. Therefore, in this work, the techno‐functional properties of starch–pectin complexes formed by extrusion are investigated. Mixtures of isolated native Pozolero maize starch "HPZ1" and pectin of low degree of methyl‐esterification at four concentrations (0%, 2%, 5%, and 7%) are used. The starch–pectin blends are processed in a single screw extruder with constant variables: temperature, screw speed, and moisture. Morphology, X‐ray diffraction, thermal properties, and techno‐properties are studied. A protective effect of pectin on the starch granules is observed, as evidenced by a matrix involving starch granules. Extrusion results in a partial gelatinization of the starch granules and alters their thermal and pasting properties with the peak temperature increasing with increasing pectin concentration. Extrusion allows both carbohydrates to interact with each other. Finally, the results show that the starch–pectin complexes are ingredients with desirable techno‐functional properties that can be integrated into a food system and add value to Mexican criollo maize. [ABSTRACT FROM AUTHOR]

This study reports the design and preparation of thermoplastic polyurethane (TPU), TPU/Cloisite 30B (0.4, 0.8, and 1.2 wt %) nanocomposites, and TPU/Irganox 1010 (0.5, 1, and 1.5 wt%) through a semi-batch method in an internal mixer and glass reactor. For this purpose, poly (ethylene adipate) was reacted with 4,4'-methylene diphenyl isocyanate to obtain the prepolymer and subsequently cured with 1,4-butanediol (BD) as chain extender to obtain the TPU sample. To accurately evaluate the curing reaction time (6 min), samples were taken from the internal mixer at specified intervals and then subjected to ATR-FTIR analysis (at 2, 4, and 6 min). Good distribution and dispersion of nanoclays in the resulting TPU nanocomposites were confirmed by XRD and scanning electron microscopy. Thermogravimetric analysis showed that the T5% and T50% of the TPU nanocomposite (TPU/Cloisite 30B (1.2 wt%)) were 15 and 33 °C higher compared to TPU-Internal. Similarly, the tensile strength of the TPU nanocomposite (TPU/Cloisite 30B (1.2 wt%)) was improved by about 25% compared to TPU-Internal. DMTA analysis revealed that the tan δ was decreased due to steric hindrance of Irganox 1010 on TPU chain mobility. Additionally, the tanδ peak for TPU-Internal was shifted from − 5.35 °C to 7.10 °C and − 1 °C for TPU 6 and TPU 3, respectively. [ABSTRACT FROM AUTHOR]

Al–Zn–Mg–Cu alloys have been prepared using the gravity die-casting process. The influence of copper addition on microstructure, mechanical and thermal properties are studied. The experimental alloys were prepared using 5754 alloys, Al–Cu alloys, and pure zinc (solid form). Alloys are mechanically stirred for uniform distributions of alloying elements and precipitate phases. Four alloys with different copper weight percentages (0.02 wt%, 0.89 wt%, 1.57 wt%, and 3.34 wt%) were prepared. The α-Al and η (MgZn2) phases are observed in as-cast Al–Zn–Mg alloy. The addition of copper in Al–Zn–Mg alloys formed a θ phase (Al2Cu). Micro-Vickers hardness of Al–Zn–Mg–Cu alloy increased (from 116 HV1 to 133 HV1) with copper addition (0.02–1.57 wt%) at firstly due to the formation of θ phase (Al2Cu). Then, micro-Vickers hardness decreases due to high amounts of precipitates. Copper addition reduces the melting point (623–612 °C) and precipitation temperature (472–466 °C) of aluminum alloy. Al–Zn–Mg alloys have tensile strength of 422 MPa due to precipitates phase formation of η and T phases, solid solution strengthening (zinc and magnesium). Copper addition increases tensile strength due to the formation of θ phases. After achieving a strength of 486 MPa at an elongation of 3.72% (1.57 wt% Cu), tensile strength reduces due to a higher amount of precipitates. [ABSTRACT FROM AUTHOR]

This study highlights the advantages of employing acetylation to enhance the morphology and thermal properties of cellulose nanocrystals (CNCs) derived from maize stalks. Utilizing a green synthesis approach for CNC extraction, this research presents a novel comparison between green extracted CNCs, and their acid hydrolysed, followed by their acetylated counterparts (ACCNCs). This comparison reveals significant improvements in the properties of acetylated CNCs over those produced through conventional acid hydrolysis. The study employs advanced characterization techniques, including Fourier Transform Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Thermogravimetric Analysis (TGA), to analyze untreated maize stalk extracted cellulose, green extracted CNCs, and acetylated CNCs. FTIR spectroscopy identifies changes in functional groups, underscoring the efficacy of the extraction and modification processes. XRD analysis demonstrates a beneficial transformation from cellulose I to cellulose II allomorphs post-acetylation, with increased crystallinity index values indicating effective removal of amorphous regions. SEM imaging reveals the preservation of rod-like structures in CNCs, while acetylated CNCs exhibit advantageous morphological changes, such as reduced nanocrystal length and increased branching. TGA results show superior thermal stability in green extracted CNCs and favorable thermal degradation behavior in acetylated CNCs. Overall, this study underscores the potential of acetylation to develop sustainable nanomaterials with tailored properties, offering significant advancements for various applications. Emphasizing the advantages of the prepared ACCNCs and the green synthesis method over traditional acid hydrolysis extraction, this research paves the way for innovative applications in diverse fields. [ABSTRACT FROM AUTHOR]

Clathrates have been reported to form in a variety of different structure types; however, inorganic clathrate-I materials with a low-cation concentration have yet to be investigated. Furthermore, tin-based compositions have been much less investigated as compared to silicon or germanium analogs. We report the temperature-dependent structural and thermal properties of single-crystal Eu2Ga11Sn35 revealing the effect of structure and composition on the thermal properties of this low-cation clathrate-I material. Specifically, low-temperature heat capacity, thermal conductivity, and synchrotron single-crystal x-ray diffraction reveal a departure from Debye-like behavior, a glass-like phonon mean-free path for this crystalline material, and a relatively large Grüneisen parameter due to the dominance of low-frequency Einstein modes. Our analyses indicate thermal properties that are a direct result of the structure and composition of this clathrate-I material. [ABSTRACT FROM AUTHOR]

Clathrates have been reported to form in a variety of different structure types; however, inorganic clathrate-I materials with a low-cation concentration have yet to be investigated. Furthermore, tin-based compositions have been much less investigated as compared to silicon or germanium analogs. We report the temperature-dependent structural and thermal properties of single-crystal Eu2Ga11Sn35 revealing the effect of structure and composition on the thermal properties of this low-cation clathrate-I material. Specifically, low-temperature heat capacity, thermal conductivity, and synchrotron single-crystal x-ray diffraction reveal a departure from Debye-like behavior, a glass-like phonon mean-free path for this crystalline material, and a relatively large Grüneisen parameter due to the dominance of low-frequency Einstein modes. Our analyses indicate thermal properties that are a direct result of the structure and composition of this clathrate-I material. [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 reactions of copper(ii) and zinc(ii) acetates with anions of 5-phenylfuran-2-carboxylic acid (Hphfur) and 5-nitro-1,10-phenanthroline (nphen) or 2,2′-bipyridine (2,2′-bpy) in the MeOH/MeCN system afforded mononuclear complexes of the composition [Cu(phfur)2(nphen)H2O] (1) and [Zn(phfur)2(2,2′-bpy)]•H2O (2). The structures of these complexes were determined by X-ray diffraction analysis (XRD). According to the XRD data, the copper atom in molecular complex 1 is in a distorted square-pyramidal environment (SQ(CuN2O3) = 0.68); the zinc atom in molecular complex 2, in a distorted trigonal-bipyramidal environment (SQ(ZnN2O3) = 3.87). The supramolecular level of 1 is mediated by intermolecular π–π interactions between the aromatic moieties of the ligands and represents a 3D supramolecular structure. in the structure of 2, the water molecules of crystallization are involved in intermolecular hydrogen bonds, resulting in the formation of centrosymmetric hydrogen-bonded dimers. The supramolecular level of 2 is mediated by C—H⋯O and C—H⋯π interactions. According to the simultaneous thermal analysis, complexes 1 and 2 are characterized by different types of thermal destruction. Thus, the explosophoric groups in the ligands of compound 1 are responsible for an intense exothermic effect. The results of biological assays show a certain correlation between the type of the substituted moiety in the heterocycle and the activity against the non-pathogenic Mycolicibacterium smegmatis strain. [ABSTRACT FROM AUTHOR]

In chemical reactions of copper(II) acetate dihydrate with imidazolium azide salts in ethanol solution several new homoleptic azidocuprates(II) were obtained. In dependency of the used counter cation various different azidocuprate moieties were crystalized. The doubly charged DMMDIm2+ cation facilitates the formation of mononuclear [Cu(N3)4]2− complex anions, while the utilisation of the (PeMIm)+ ion enables the isolation of a dinuclear [Cu2(N3)6]2− salt. By using the unsymmetrical imidazolium ions (BMIm)+ or (EMIm)+ salts with the trinuclear [Cu3(N3)8]2− complex anion are obtained. With the (DML)+ cation an azidocuprate(II) crystallizes, which contains both [Cu(N3)4]2− and the [Cu2(N3)6]2− anion. The anions in the salt with the (PeMIm)+ cation are interconnected through further Cu−N bonds and form layers with a 2D‐honeycomb structure. The trinuclear units in the (BMIm)+ and the (EMIm)+salts form coordination strands of different structures. [ABSTRACT FROM AUTHOR]

This study utilizes modulation of ionic disorder and electronegativity differences for targeted component design of high-entropy ceramic compositions. A series of novel multicomponent ceramics with the general formula (LaGdYSm) x 2 Yb x 1 Zr 2 O 7 (x 1 +4x 2 = 2, x 1 = 0.6,0.4,0.2,0) were prepared by solid-state reaction. The evolution patterns of their microstructures were analyzed using XRD and TEM, and the anti-sintering ability and thermophysical properties were evaluated. The results confirm that the multicomponent ceramics gradually transform from the coexistence of pyrochlore/fluorite dual-phase structure to pyrochlore structure with the tuning of the size disorder degree. After 50h of exposure to air at 1500 °C, the ceramics retained excellent phase stability. Segregation of La and Yb elements with large differences in radius size occurs, forming a mixture of the La-rich pyrochlore and the Yb-rich fluorite phases. The specimen with the maximum size disorder exhibits the lowest grain growth rate and the greatest thermal insulation properties. Large lattice distortions and sluggish diffusion effects are responsible for the mutual inhibition of grain growth in the two-phase coexistence zone. The thermal insulation properties of the ceramics show well correlated with the degree of the size disorder, further validating the effectiveness of the component design. Meanwhile, the thermal expansion coefficients of prepared ceramic can reach 11.49 × ∼11.58 × 10−6 K−1 at 1000–1100 °C. The customization principles used in this work fill a gap in the compositional design methodology for multicomponent lanthanum zirconate-based high-entropy ceramics. It is essential for developing rare-earth zirconates with tunable thermophysical properties in the area of thermal barrier coatings. [ABSTRACT FROM AUTHOR]

Poly (vinyl alcohol) (PVA) composite films containing oxidized graphitic carbon nitride (GCN-ox) were successfully prepared by solution casting. First, GCN was synthesized and delaminated, and then its surface was oxidized. Composites containing 0.5%, 1%, 2%, 3%, 4%, and 5% by mass of GCN-ox were prepared. Composites were characterized by XRD, SEM, FTIR-ATR, and UV-vis analyses. In addition, tensile strength and elongation at break values of composite samples were determined by mechanical tests. Because of the increasing interfacial interaction between GCN-ox and the PVA matrix, GCN-ox acted as a reinforcing filler to enhance the mechanical properties. PVA/GCN-ox composites could reach 52.5 MPa tensile strength and 7.27 GPa tensile modulus, respectively. Optical studies showed that the energy bandwidth of the pristine PVA reduced from 4.983 eV to 3.813 eV with the addition of 5% GCN-ox. [ABSTRACT FROM AUTHOR]

The compound Cu2Se has been synthesized and its crystal structure has been studied. Structural studies were carried out by angle dispersive XRD method. Structural phase transition was detected by analyzing the spectra obtained in the temperature range T = 2 9 0 –1000 K. It was found that, under normal conditions, this compound has an orthorhombic crystal structure. At a temperature T = 4 0 7 K, a phase transition occurs from orthorhombic to cubic with the formation of a highly symmetrical phase. The values of crystallographic parameters were determined for each phase. [ABSTRACT FROM AUTHOR]

The modification method of aluminosilicate clays and the modifier content have a decisive influence on the structure and properties of the obtained nanocomposites. Therefore, the development and research of new techniques of nanoclays modification are of great importance for polymer nano-chemistry. The work studied the modification of montmorillonite (MMT) using polyvinylpyrrolidone (PVP) in an aqueous colloidal solution with the subsequent separation of three separate fractions of the solution according to the previously developed method. The influence of the initial mass ratio of components (MMT/PVP) on the structure and thermal properties of the modified MMT in each solution layer was determined. Scanning electron microscopy (SEM), X-ray diffraction (XRD), thermal gravimetry (TG), differential scanning calorimetry (DSC), and Fourier-transform infrared (FTIR) spectroscopy were used for research. It was established that the mass ratio of components in the initial solution has almost no effect on the structure of MMT in the top and middle solution layers, but significantly affects the yield of final products. Different structures can be obtained in the bottom layer of the solution. Still, intercalated MMT was obtained exclusively at the mass ratio of MMT/PVP = 1:2. In addition, the work investigated the structure and thermal properties of modified montmorillonites with the same PVP content, and it has been proven that such composites have dissimilar structures and properties when obtained by different methods. [ABSTRACT FROM AUTHOR]

Demand for natural fibers has increased in recent years due to the requirement for biodegradable materials. Owing to the increasing awareness on the overuse and over-dumping of plastics in the environment, the current work focused on a solution by using tree leaves as a particulate reinforcement which is one of the common waste products of trees. In this regard, Norfolk pine (NOP) tree leaf particulates filled High-Density Polyethylene (HDPE) composites were fabricated through injection moulding technique with different filler weight % of 0, 10, 20, 30, 40, and 50 wt. %. The study of the crystalline structure of the fillers and the detection of functional compounds in the materials were carried out through X-ray diffraction (XRD) and Energy dispersive X-ray spectroscopic (EDX) analysis. Tensile strength, compressive strength, and flexural strength of the fabricated composite specimens were also assessed. Results revealed that the mechanical properties of the 30 wt. % pine tree leaf-filled HDPE composites were found to be superior when compared to pure HDPE composites. The failure surface morphology of the composite samples was examined using scanning electron microscopy (SEM). The melting point and decomposition of 30 wt. % NOP leaf particulate-filled HDPE composites specimen, whose mechanical properties were higher, were examined using thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC). From the results, it was found that NOP fillers can be used as an effective reinforcement in polymer composites. [ABSTRACT FROM AUTHOR]

Synthesis of a new series of mesogenic dimers and investigation of their liquid crystalline properties with thermal, optical and XRD methods is reported. Unlike dimeric mesogens studied to date, the presently reported dimers are derived from a single-ring mesogen containing a partially fluorinated dodecyl chain, which effects nanosegregation and formation of a lamellar phase. The reported four diesters with the odd-membered connecting alkyl chain exhibit a SmA phase. In contrast, two even-membered analogues have higher melting points and do not exhibit mesogenic behaviour. [ABSTRACT FROM AUTHOR]

In this study, the influence of the incorporation of eucalyptus (EO), tea tree (TT) and rosemary (RO) essential oils and Chiriyuyo extract (CE) on the structure and properties of thermoplastic starch (TPS) obtained from potato starch, glycerin and water was evaluated. All oils and the extract were used at a concentration of 0.5 g/100 g of TPS, while for TT, the effect of the concentration was also studied. The mixtures obtained were processed by extrusion and thermocompression molding. The sheets were characterized by XRD, FTIR, TGA, SEM and analyses of their mechanical properties, antimicrobial characteristics and biodegradability. The results show that the use of small concentrations of the oils in 70TPS does not induce changes in the TPS structure according to the results of XRD, FTIR and TGA, with each essential oil and CE affecting the mechanical properties unevenly, although in all cases, antimicrobial activity was obtained, and the biodegradability of TPS in soil was not modified. An increase in the concentration of TT in 60TPS causes marked changes in the crystallinity of TPS, providing a greater modulus with a higher concentration of TT. Regardless of the amount of TT, all sheets maintain antimicrobial characteristics, and their biodegradation in soil is delayed with a higher oil content. [ABSTRACT FROM AUTHOR]

The objective of this investigation is to enhance the compatibility between the poly (styrene-co-acrylonitrile) (SAN) and ethylene-propylene-diene monomer rubber (EPDM) in the presence of organically modified montmorillonite (OMMT) to achieve better impact strength of this hybrid material by utilizing styrene-ethylene-butylene-styrene grafted with maleic anhydride (SEBS-g-MAH) as a compatibilizer. The effectiveness of (SEBS-g-MAH) as a compatibility agent is based on the analysis of the rheological, mechanical, and morphological properties of the final products. Mixtures were produced through melt blending using Brabender mixer. X-ray diffraction (XRD), scanning electron microscopy (SEM), tensile and impact tests were used to examine the structural, morphological, and mechanical characteristics of SAN/EPDM composites with and without OMMT and SEBS-g-MAH. According to the SEM analysis and XRD patterns, the SEBS-g-MAH reduced the EPDM phase's domain size, exfoliated structure and homogeneous dispersion of the OMMT silicate layers was observed. Based on the ATG results, the addition of SEBS-g-MA did not substantially alter the thermal stability of SAN/EPDM/OMMT nanocomposites. The stiff clay's competing effect, along with the tough effects of the EPDM and SEBS-g-MAH elastomers, have a significantly impact on the modulus and impact strength, resulting in balanced properties. [ABSTRACT FROM AUTHOR]

In this study, quaternary phosphonium salt (P4) was prepared, vermiculite (VMT) was modified by P4, and P4@VMT/poly (butylene adipate‐co‐terephthalate) (PBAT) composite film was prepared by the solution method. The structure of the synthesized P4 was determined by nuclear magnetic resonance and infrared. The structure and performance of P4 modified vermiculite were explored and analyzed by particle size, XRD, infrared and micro‐morphology. The structure, thermal properties, crystallization properties, rheological properties, cross‐section morphology, tensile properties and antibacterial properties of pure PBAT film and P4@VMT/PBAT composite film were tested and compared. The results show that the crystallization temperature and melting temperature of P4@VMT/PBAT composite film are higher than those of pure PBAT film. With the increase in P4@VMT content, the thermal stability of the composite film becomes worse, and the crystallization enthalpy, melting enthalpy and crystallinity also decrease, while the storage modulus, loss modulus and complex viscosity of P4@VMT/PBAT composite film increase significantly. In addition, compared with pure PBAT film, the tensile strength of P4@VMT/PBAT‐20% composites decreased by 12.0% and the elongation at break decreased by 95.7%. Highlights: Successful synthesis of phosphonium quaternary P4 and modification of vermiculite.The properties of P4@VMT/PBAT composite films with different contents were studied. [ABSTRACT FROM AUTHOR]

Crystal structure, thermal stability, and the process of scandium tris-methylcyclopentadienyl Sc(MeCp)3 evaporation are studied. It is shown by XRD that crystals of this compound with the C2/c space group and the following parameters at 150 K are formed from the gas phase and from the solution: a = 7.9568(4) Å, b = 13.7620(6) Å, c = 28.239(2) Å, β = 107.4860(10)°, V = 2949.3(3) Å3, Z = 8, Dcalc = 1.217 g/cm3. The violation of the crystal packing order is manifested as diffuse scattering accompanied by single-crystal Bragg diffraction. The obtained data suggest that the complex has the Sc(η5-MeCp)2(η1-MeCp) structure with Sc–Z distances equal to 2.26-2.37 Å, where Z is the center of the η5-MeCp species or the C atom (for η1-MeCp). The NMR data obtained for the Sc(MeCp)3 samples, which were kept for 7 days at 423 K, 453 K, and 483 K, indicate that the substance undergoes noticeable decomposition only at the highest temperature. Temperature dependences of the saturated vapor pressure of the complex are measured independently by the flow method (transpiration) (392-469 K) and by the static method (441-514 K). As a result of joint processing of the tensimetry data, the following thermodynamic parameters of Sc(MeCp)3 evaporation are determined: ΔevH0(458.5) = 82.5±1.1 kJ/mol, ΔevS0(458.5) = 135±2 J/(mol·K). [ABSTRACT FROM AUTHOR]

SnxSb20Se80−x bulk glasses were prepared using the well-known melt quenching technique, where x was taken as 7.5 at.%, 9.5 at.%, 11.5 at.% and 13 at.%. X-ray diffraction (XRD) and differential scanning calorimetery (DSC) were used to monitor the crystallinity and transition temperatures, respectively. XRD examinations showed that the 7.5 at.% and 9.5 at.% compositions were purely amorphous, while the other two compositions exhibited a crystalline structure. DSC thermograms demonstrated that 7.5 at.% and 9.5 at.% alloys had a single crystallization peak, whereas for the 11.5 at.% and 13 at.% alloys, two exothermic peaks and three peaks appeared. The glass stability and kinetics of amorphization and crystallization were studied using different approaches. The correlation between topological constraints and the dimensionality of the growth was established. [ABSTRACT FROM AUTHOR]

This article evaluated the effect of using mining waste on the mechanical, physical, thermal, and microstructural properties of cement-wood panels. The percentages of 10, 20, 30, and 40% were evaluated as replacing cement with mining waste. The wood particles of Pinus oocarpa were evaluated for their chemical, anatomical, and physical characteristics, and the mining waste was evaluated for its granulometry, chemical composition, and inhibition index. The composites were evaluated for their physical-mechanical properties, X-ray diffraction and infrared spectroscopy analysis, microstructural, thermal, and durability. All evaluated treatments met the requirements of the Bison standard for MOR and MOE for static bending and internal bonding, even after accelerated aging. It was possible to conclude that it is feasible to replace 40% of cement with mining waste for the production of cement-wood panels in industrial scale. [ABSTRACT FROM AUTHOR]

Two new Ag(I) complexes with 1,1,1,5,5,6,6,6-octafluorohexane-2,4-dionate ion (Ofhac) and π‑donor neutral ligands, vinyltriethylsilane (VTES) or cycloocta-1,5-diene (COD), were synthesized with the goal to expand the library of silver precursors for chemical vapor deposition. The products were characterized by elemental analysis and IR and NMR spectroscopy. The complex [Ag(VTES)(Ofhac)] (I) was liquid under standard conditions; the temperature of its crystallization was below –20°C. Treatment of I with benzene gave rise to crystals of [Ag4(C6H6)2(Ofhac)4]∞ (II), which was confirmed by NMR and X-ray diffraction (CCDC no. 2232810). The structure of [Ag(COD)(Ofhac)]2 (III) was established by X-ray diffraction (CCDC no. 2232809). The binuclear molecules are formed due to the μ2-κ1(O):κ1(O') function of the Ofhac ligands (Ag–O, 2.458(2)–2.461(2) Å), while COD is κ2-η2:η2-coordinated (Ag–C, 2.420(17)–2.684(11) Å). The thermal properties of I and III in comparison with analogues containing 1,1,1,5,5,5-hexafluoropentane-2,4-dionate ion (Hfac) were studied by thermogravimetry. [ABSTRACT FROM AUTHOR]

Corrosion is a harmful processes which by definition is a chemical or electrochemical reaction between a substance (usually a metal) and the environment which leads to a change in the properties of the substance and has destructive effects. In this study, new composites consisting of Al/WS2/ZnTerp-2TH with 5 and 10 wt.% ZnTerp-2TH were prepared and the results were fully compared. Al/WS2 played the role of matrix and ZnTerp-2TH played the role of reinforcement. In other words, as a novelty to prevent the corrosion of Al/WS2, ZnTerp-2TH is designed and synthesized and showed good results when the corrosion ratio was reduced by the existence of ZnTerp-2TH. Furthermore, the NMR and mass analysis of ZnTerp-2TH were carried out, and the thermal properties, X-ray diffraction, Fourier-transform infrared (FTIR) spectroscopy, morphology, energy-dispersive X-ray spectroscopy (EDX) analysis and corrosion behavior of the composites were also discussed in detail. The crystal size values of composites were calculated by the modified Scherrer method 34, 26 and 27 nm for Al/WS2, Al/WS2/5 wt.% ZnTerp-2TH and Al/WS2/10 wt.% ZnTerp-2TH, respectively. The microstructural examination of the specimens showed that the reinforcing phase (ZnTerp-2TH) has a favorable distribution on the surface of Al/WS2 when it covers the cracks and holes. In addition, the corrosion investigation results showed that the addition of ZnTerp-2TH to Al/WS2 can improve the corrosion resistance when the Ecorr and Icorr values of Al/WS2/10 wt.% ZnTerp-2TH were recorded in tandem −724 mV/decade and 5 uA cm−2. [ABSTRACT FROM AUTHOR]

In this paper, a novel hydrogen-bonded liquid crystalline binary complex system was synthesized from pure mesogenic 4-(octyloxy)benzoic acid (8OBA) and non-mesogenic n-aminobenzoic acid (nABA, n = 3, 4) chemicals. Differential scanning calorimeter (DSC) experiments were performed to investigate the thermal properties of the synthesized samples, and polarized optical microscopy (POM) experiments were performed to investigate the mesogenic phase textures. The DSC and POM results showed that the phase sequence was Cr ↔ SmA ↔ SmC ↔ N ↔ I during continuous heating and cooling cycle. In addition, the thermal stability factor, phase transition entropy, and phase transition activation energy were calculated using DSC data. According to the calculated values, it was concluded that the mesogenic phases of the synthesized complexes occur regularly and the most stable phase is the SmC phase. Moreover, the optical tilt angle value for the SmC phase was measured and it was seen that the value increased up to 29° and 30° for 8OBA/4ABA and 8OBA/3ABA complexes, respectively. The formation of hydrogen bonds between the mesogenic and non-mesogenic molecules in the synthesized mesogenic structure was confirmed by Fourier-transformed infrared spectroscopy (FTIR). Furthermore, XRD results showed that the molecular ordering of the synthesized hydrogen-bonded 8OBA/4ABA and 8OBA/3ABA binary complexes occur in a monoclinic structure in the solid phase. [ABSTRACT FROM AUTHOR]

Stretching has been extensively applied for decades in the production of polyimide (PI) materials with improved mechanical, electrical, and thermal properties. Meanwhile, a detailed understanding of the molecular motions during stretching is still limited. Herein, the thermomechanical behaviors of uniaxially stretched PI films prepared from 3,3′,4,4′‐biphenyl tetracarboxylic dianhydride (BPDA) and 2,2′‐bis (trifluoromethyl) benzidine (TFDB) are studied, and the possible molecular motions responsible for the sub‐glass transition temperature (Tg) stretchability and retraction after stretching are systematically investigated. Based on X‐ray diffraction and dynamic mechanical analysis, it is revealed that both the sub‐Tg stretchability and retraction correlates with β2 relaxation, which originates from the highly cooperative molecular motions of conformational rotations involving segmented BPDA units. A thermodynamic model is established and applied for the analysis of the retraction behaviors of stretched BPDA‐TFDB PI films. It is found that the increase of entropy under stretching plays a significant role in most retraction cases. However, as the stretching temperature increases, the α relaxation‐correlated large‐scale molecular motions emerge. Such motions partially counterbalance the conformational rotations of BPDA segments, leading to an enhanced contribution of enthalpy decrease during the retraction of BPDA‐TFDB PI films. [ABSTRACT FROM AUTHOR]

This work aimed to study the influence of the polybutylene succinate (PBS) content on the physical, thermal, mechanical, and chemical properties of the obtained polylactic acid (PLA)/PBS composite fibers. PLA/PBS blend fibers were prepared by a simple melt-blown process capable of yielding nanofibers. Morphological analysis revealed that the fiber size was irregular and discontinuous in length. Including PBS affected the fiber size distribution, and the fibers had a smoother surface with increased amounts of added PBS. Differential scanning calorimetry analysis (DSC) revealed that the crystallization temperature of the PLA sheet (105.8 °C) was decreased with increasing PBS addition levels down to 91.7 °C at 10 wt.% PBS. This suggests that the addition of PBS may affect PLA crystallization, which is consistent with the X-ray diffraction analysis that revealed that the crystallinity of PLA (19.2%) was increased with increasing PBS addition up to 28.1% at 10 wt% PBS. Moreover, adding PBS increased the tensile properties while the % elongation at break was significantly decreased. [ABSTRACT FROM AUTHOR]

This research aimed to prepare nonwovens from polylactic acid and polybutylene succinate using the melt-blown process while varying the melt-blown process parameters, including air pressure (0.2 and 0.4 MPa) and die-to-collector distance (15, 30, and 45 cm). Increasing the air pressure and die-to-collector distance resulted in the production of smaller fibers. Simultaneously, the tensile strength was dependent on the polymer, air pressure, and die-to-collector distance used, and the percentage elongation at the break tended to increase with an increasing die-to-collector distance. Regarding thermal properties, the PBS nonwovens exhibited an increased level of crystallinity when the die-to-collector distance was raised, consistent with the degree of crystallinity obtained from X-ray diffraction analysis. Polylactic acid could be successfully processed into nonwovens under all six investigated conditions, whereas nonwoven polybutylene succinate could not be formed at a die-to-collector distance of 15 cm. However, both polymers demonstrated the feasibility of being processed into nonwovens using the melt-blown technique, showing potential for applications in the textile industry. [ABSTRACT FROM AUTHOR]

BaxCo1‐xFe12O19 (x = 0.2, 0.4, 0.6, & 0.8) nanoparticles are prepared via hydrothermal method. The hexagonal structure of x = 0.2 – 0.8 samples is confirmed by X‐ray diffraction patterns. Morphology indicated the existence of nanospheres like grains. The magnetic and dielectric parameters are clearly discussed as a function of composition at room temperature. The increase of Ba‐content reduced the magnetization from 56.1 to 49.7 emu g−1, and at higher Ba‐content, it is increased from 49.7 to 57.3 emu g−1. The x = 0.6 content offered the high ε' ≈9.54 and low ε" ≈0.12 values suitable for charge storage, and low noise device applications. Further, the thermal properties (using thermogravimetry (TG)‐differential thermogravimetry (DTG) & TG‐differential scanning calorimetry (DSC)) are elucidated in detail. [ABSTRACT FROM AUTHOR]

Orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 nanofibers were prepared by electrospinning followed by a heat treatment. The effects of post-annealing temperatures on the phase composition, microstructure and morphology were investigated by XRD, SEM, HRTEM and XPS. Negative thermal expansion (NTE) behaviors of the In 0.5 Sc 1.5 Mo 3 O 12 nanofibers were analyzed by high-temperature XRD. Results indicate that the as-prepared In 0.5 Sc 1.5 Mo 3 O 12 nanofibers show an amorphous structure with smooth and homogeneous shape. The average diameter of the as-prepared In 0.5 Sc 1.5 Mo 3 O 12 nanofibers is around 515 nm. Well crystallized orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 nanofibers could be prepared after post-annealing at 550 °C for 2 h with an average diameter of about 192 nm. The crystallinity of In 0.5 Sc 1.5 Mo 3 O 12 nanofibers gradually improved with the increase of annealing temperature. However, too high post-annealing temperature leads to a damage of sample's fiber structure. The high-temperature XRD results reveal that In 0.5 Sc 1.5 Mo 3 O 12 nanofibers show an anisotropic NTE, and the coefficients of thermal expansion (CTEs) along a -axis and c -axis were −5.95 × 10−6 °C−1 and -3.54 × 10−6 °C−1, while the one along b -axis is 5.61 × 10−6 °C−1. The volumetric CTE of In 0.5 Sc 1.5 Mo 3 O 12 nanofibers is −3.90 × 10−6 °C−1 and the linear one is 1.3 × 10−6 °C−1 in 25–700 °C. [ABSTRACT FROM AUTHOR]

High-performance polymer nanocomposites utilizing different-sized nanofillers had a lot of interest recently. Due to their distinct structural, and thermal characteristics. Multi-wall carbon nanotubes (MWCNT) and nanoclay (NC) have the most interest among the numerous types of reinforcing as filler elements for a polymer. The formation of hybrid from MWCNT and NC at various loadings (0.5%, 1%, and 2wt%) on the characteristics of epoxy polymer have been assessed in this work. The specimens have been created using solution blending procedures with the addition of solvent ethanol at a ratio of 1:1 for dispersed nanofillers, and then they have been re-mixed with epoxy. Tests like X-Ray diffraction (XRD), and thermal conductivity were used to identify properties of epoxy. According to the test results, the thermal conductivity rise as the filler content rises at 1wt%, then start to decrease after 1wt%. The sample with the hybrid filler loading of 1 wt% produced the best performance. Since hybrid epoxy exhibits the best result of the thermal conductivity 135% over MWNT and NC nanocomposites of 1 wt.% reached 0.3568 W/m.K in the increased thermal conductivity property. By examining the EP nanocomposites XRD pattern. The hybrid of epoxy nanocomposites exhibits all of the NC and MWCNT characteristic peaks. Since interactions between the filler and the epoxy cause a shift in the peak location of 1wt%. Due to the homogeneity of the nanofillers entire epoxy matrix, there may be changes in the intensity or location of the peaks at 1% for 2θ= 20.13°, which corresponds to an interlayer distance of d=0.461nm. [ABSTRACT FROM AUTHOR]

The iron-based ceramic GdFeAsO has been prepared by the solid-state reaction method. To identify the ceramic and its multiple applications we have performed structural, micro structural and electrical characterizations of the sample. The crystalline size and structure are calculated at room temperature using the X-ray Diffraction (XRD) technique. Tetragonal structure has been ensured from XRD. The lattice strain of the crystal is obtained using W.H. Plot, which ensured the structural stability of the crystal. The field emission scanning electron microscopy (FESEM) technique is used to study the surface morphology of the sample. Polycrystalline grains having spherical and cylindrical sizes of ranges 1-3 micrometer are obtained. The observed prominent peaks at 107.1cm−1,150.4cm−1,216.6cm−1,296.6cm−1,344.6cm−1 and 440.37cm−1 in the Raman spectra of the sample, are for the cubic phase of the Gd2O3 in the GdFeAsO compound material. The peak at 623.0cm−1 corresponds to α-Fe2O3 in the spectra reveals the presence of impurity oxide phases. The broad peaks in the Differential Scanning Calorimetry (DSC) graph at about (290°C) and (600°C) reveals the initiation of slow crystallization of the sample within the given temperature range. The dielectric properties such as the dielectric constant (εr) and loss tangent (tanδ) of the sample have been studied at different temperatures and frequencies with LCR meter. The high value of dielectric constants is seen to exist in the materials. There are two dielectric anomalies that are observed at lower and higher temperature region. The magnetic measurement has been performed by using Vibrating Sample Magnetometer (VSM) at room temperature and showed the non linearity in the magnetization versus field curve.

In addition to being bio-degradable, cellulose nanocrystals (CNC) provide high mechanical strength to polymer composites. They exhibit outstanding properties like high strength-to-weight ratio, abundant surface functional groups and sustainability. In this study, we prepared nanocomposites of poly (ethylene-co-methyl acrylate) (EMA) and CNC using the melt-mixing technique. The mechanical properties of EMA were improved after adding CNC to it. The ultimate tensile stress and maximum elongation increased from 6 MPa and 860% (for pristine EMA) to 9.5 MPa and 1090% (for 2 wt.% EMA/CNC composite). Thermal properties of the EMA/CNC composites were analyzed by using DSC and TGA analysis. The dispersion of CNC in the composite was analyzed by SEM and XRD analyses. The EMA/CNC composites showed interesting birefringence properties on analysis via polarized optical microscopy (POM). The POM analysis indicated that the CNC in composites aligns themselves in the direction of applied stress, enhancing the mechanical strength of nanocomposites. Biodegradation of the bio-composite was also studied via soil-burial test. [ABSTRACT FROM AUTHOR]

A transparent white crystalline product, K[(C2F5)3PF3] (KFAP), has been synthesized via a one-pot route. Difluorotris(pentafluoroethyl)phosphorane was reacted first with aqueous HF then with K2CO3 or KHCO3 in a solution. Isolation of the intermediate, tris(pentafluoroethyl)trifluorophosphoric acid H[(C2F5)3PF3] (HFAP), was not carried out. The salt has been characterised by powder and single crystal X-ray diffraction. The single-crystal structure shows a monoperiodic coordination polymer involving K∙∙∙F bridging interactions to be present. The thermal characteristics and behaviour of KFAP have been established by simultaneous TGA-DSC measurements. [ABSTRACT FROM AUTHOR]

Here, seven new double-complex salts, [M1(NH3)6][M2(C2O4)3] (M1, M2 = Co, Rh) and K3[Rh(NH3)6][Rh(C2O4)3]2∙6H2O types, are synthesised. The crystal structure and composition of DCS (double-complex salts) are studied by SCXRD, XRD, CHN and IR methods. The complex salts of the [M1(NH3)6][M2(C2O4)3] (M1, M2 = Co, Rh) type can be crystallised both as a crystalline hydrate [M1(NH3)6][M2(C2O4)3]·3H2O (sp. gr. P-3) and as an anhydrous complex (sp. gr. P-1) depending on the synthesis conditions. The process of [Rh(NH3)6][Rh(C2O4)3] formation is significantly dependent on the synthesis temperature. At room temperature, a mixture is formed comprising [Rh(NH3)6][Rh(C2O4)3] and K3[Rh(NH3)6][Rh(C2O4)3]2∙6H2O, while the [Rh(NH3)6][Rh(C2O4)3] target product crystallises at elevated temperatures. The thermal behaviour of double-complex salts is studied by the STA, EGA-MS, IR and XRD methods. The complete decomposition of complex salts in helium and hydrogen atmospheres resulting in metals or CoxRh1−x solid solutions is achieved at temperatures of 320–450 °C. [ABSTRACT FROM AUTHOR]

Nanocellulose derived from cellulose, the abundant natural polymer, is used in various applications due to its superior chemical, mechanical and thermal properties along with good biocompatibility and biodegradability. This paper reports an investigation of the extraction of nanocellulose from two freely available natural precursors-watermelon rinds and water hyacinth leaves. Cellulose isolation was carried out through chemical methods, including acid and alkali treatments followed by bleaching. The chemical composition, percentage crystallinity and particle size were studied using various characterization techniques. FTIR spectra indicate the removal of hemicelluloses, pectin, and lignin resulting in the effective isolation of cellulose from both precursors. Results of XRD indicate a high concentration of Cellulose Nanocrystals (CNCs) in the treated sample. The FESEM and SEM-EDAX images also confirm the formation of CNCs. TGA and DSC results show excellent thermal stability for both CNCs. Investigations on the properties of a CNC-reinforced epoxy composite are also reported. Results indicate considerable improvement in the mechanical properties, thermal stability and thermal conductivity of the composites compared to the pristine polymer. [ABSTRACT FROM AUTHOR]

New magnesium complexes [Mg(H2O)2(ofhac)2] 1 and [Mg(tmeda)(ofhac)2] 2 (ofhac = , tmeda = N,N,N′,N′-tetramethylethylenediamine) with a 1,1,1,2,2,6,6,6-octafluorohexane-3,5-dionate ligand are prepared. The composition of these compounds is confirmed by elemental analysis and IR spectroscopy, the structure is determined by XRD. The coordination environment of magnesium is distorted octahedral in both complexes. The ofhac ligands are coordinated in the bidentate-cyclic mode; the lengths of Mg–O bonds are similar and vary within 2.033(14)-2.063(18) Å. The aqua ligands in 1 occupy cis positions (d(Mg–O) = 2.0511(18) Å, θ(O–Mg–O) = 85.0(1)°) and participate in the system of O–H...O and O–H...F hydrogen bonds forming a chain packing. The tmeda ligand in 2 performs a chelating function (d(Mg–N) = 2.212(4) Å, θ(N–Mg–N) = 81.0(6)°). The dependence of the structure and the thermal properties of the complexes on the size of the fluorinated substituent (C2F5 instead of CF3) is estimated by comparing the complex with its analogues bearing 1,1,1,5,5,5-hexafluoro-2,4-pentadionate ligands. The crystal structures of [Mg(H2O)2(L)2] are homeotypic; the analogues of [Mg(tmeda)(L)2] crystallize in different space groups. The absence of trans isomers in [Mg(H2O)2(L)2] is confirmed by powder XRD. The thermogravimetry experiments in flowing helium and sublimation tests in vacuum showed that complexes with the ofhac ligand are more volatile. Introducing a C2F5 groups into the ligand also decreases the melting point of the compounds, more significantly for aqua complexes. [ABSTRACT FROM AUTHOR]

This research sought to synthesize a new set of heteroaromatic thiazole-based polyurea derivatives with sulfur links in the polymers' main chains, which were denoted by the acronyms PU1–5. Using pyridine as a solvent, a diphenylsulfide-based aminothiazole monomer (M2) was polymerized via solution polycondensation with varied aromatic, aliphatic, and cyclic diisocyanates. Typical characterization methods were used to confirm the structures of the premonomer, monomer, and fully generated polymers. The XRD results revealed that aromatic-based polymers had higher crystallinity than aliphatic and cyclic derivatives. SEM was used to visualize the surfaces of PU1, PU4, and PU5, revealing spongy and porous shapes, shapes resembling wooden planks and sticks, and shapes resembling coral reefs with floral shapes at various magnifications. The polymers demonstrated thermal stability. The numerical results for PDTmax are listed in the following order, ranked from lowest to highest: PU1 < PU2 < PU3 < PU5 < PU4. The FDT values for the aliphatic-based derivatives (PU4 and PU5) were lower than those for the aromatic-based ones (616, 655, and 665 °C). PU3 showed the greatest inhibitory impact against the bacteria and fungi under investigation. In addition, PU4 and PU5 demonstrated antifungal activities that, in contrast with the other products, were on the lower end of the spectrum. Furthermore, the intended polymers were also tested for the presence of the proteins 1KNZ, 1JIJ, and 1IYL, which are frequently utilized as model organisms for E. coli (Gram-negative bacteria), S. aureus (Gram-positive bacteria), and C. albicans (fungal pathogens). This study's findings are consistent with the outcomes of the subjective screening. [ABSTRACT FROM AUTHOR]

Orthorhombic Sc 2 Mo 3 O 12 samples have been synthesized using ethylene glycol (EG)-assisted hydrothermal reaction. The influences of hydrothermal temperature, hydrothermal time and additive content of EG on the preparation and negative thermal expansion (NTE) behavior of Sc 2 Mo 3 O 12 samples were characterized using XRD, SEM, HRTEM, EDX, TMA and HTXRD. Results indicate that flower-like Sc 2 Mo 3 O 12 with a uniform particle size of 1–2 μm can be synthesized at 120 °C for 2 h by adding 60 ml EG. Hydrothermal temperature, time and additive content of EG have strong influences on the growth and morphology of the Sc 2 Mo 3 O 12. The average coefficients of thermal expansion (CTEs) of the Sc 2 Mo 3 O 12 prepared at 120 °C for 2 h and 200 °C for 24 h are tested to be −6.94 × 10−6 °C−1 and -7.18 × 10−6 °C−1 in 25–700 °C using TMA. HTXRD results indicate that the flower-like Sc 2 Mo 3 O 12 exhibits anisotropic NTE, and the corresponding CTEs along the a , b and c axes are −6.73 × 10−6 °C−1, 4.98 × 10−6 °C−1 and -4.78 × 10−6 °C−1 in 25–700 °C, respectively, and the corresponding linear CTE is −2.21 × 10−6 °C−1. [ABSTRACT FROM AUTHOR]