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Co-melting paracetamol with different cellulose derivatives leads to full or partial amorphization of active substance. The aim of this study was to determine whether the amorphization of paracetamol after co-melting with cellulose derivatives is stable and whether it depends on the type of cellulose derivative added and the ratio of components. Mixtures of paracetamol with cellulose derivatives containing different proportions of components were prepared. Using differential scanning calorimetry (DSC), the samples were melted and the amorphization of paracetamol was confirmed. After 2 and 4 months, the samples were reanalyzed to determine the amorphization stability during storage and the difference in the effect of different polymers on the amorphization stability. The physical mixtures were additionally tested using Fourier transform infrared (FTIR) and Raman spectroscopic methods to confirm that no solid-phase interactions were noticed. Samples were also analyzed using ultrahigh-performance liquid chromatography (UHPLC) to assess the effect of co-melting and storage on the chemical stability of paracetamol. The results show that paracetamol amorphizes after co-melting with cellulose derivatives. The crystallization of paracetamol after co-melting depends on the polymer used and the proportions of the components. No interactions between the components and the chemical stability of paracetamol in the tested samples were confirmed. [ABSTRACT FROM AUTHOR]

In order to produce suitable poly(methyl methacrylate)/poly(vinylidene fluoride) (PMMA/PVDF) films for optoelectronic and power storage uses, Ni-doped ZnO nanoparticles were added to PMMA/PVDF films. This was done in order to generate a synergistic interaction between the superior electrical characteristics of Ni and the remarkable optical characteristics of ZnO NPs. The production of Ni/ZnO in wurtzite hexagonal phase with a normal grain size of 19 nm was verified by the findings of the selected-area diffraction of electrons and X-ray diffraction techniques. By using FTIR measurements, the interaction of polymers with Ni/ZnO has been studied. The raising of the Ni/ZnO content steadily redshifted the optical band gap. With various nanoparticle concentrations, the differential scanning calorimetry (DSC) results revealed an enhancement in the temperature of melting of the PMMA/PVDF-Ni/ZnO nanocomposites films as well as decrease in the level of crystallinity. At room temperature, an AC impedance study was carried out to check the electrical conductivity. All samples' ac conductivity spectra confirmed Jonscher's power law (JPL) behavior. The PMMA/PVDF-1.5%Ni/ZnO nanocomposites were discovered to have a greater ionic conductivity (σac) of 1.10 10− 5 S/cm at ambient temperature. Research on dielectric permittivity has additionally been carried out in order to comprehend the charge storage characteristics. The findings of the experiments showed that these PMMA/PVDF-Ni/ZnO films would provide excellent options for thermal insulators, cutting-edge microelectronics, capacitive storage of energy, optoelectronic technology and other applications. [ABSTRACT FROM AUTHOR]

Large anisotropic deformation affects the physical state of a polymer glass, where the changes in the state of material are revealed by performing a differential scanning calorimetry (DSC) experiment. Previously, the deformation was applied to polymers well below their glass transition temperatures, and it was found that uniaxial compressive loading–unloading resulted in a broad exothermic peak on the DSC trace. Here we report on the effect on the subsequent DSC response of a deformation experiment performed in uniaxial extension on a ductile 50:50 co‐polymer poly(BMA‐co‐MMA) (PBMA/MMA). The deformation of up to 80% strain was applied at Tg − 30°C and Tg − 40°C, that is, closer to Tg than in the previous work. Unlike in the well below Tg deformation case, the DSC trace contains an endothermic peak followed by an exothermic peak. The magnitude of the endothermic peak as well as the asymptotic glassy heat capacity increase with the amount of mechanical work performed during the deformation cycle. [ABSTRACT FROM AUTHOR]

Polyurethane materials can be used industrially in different ways, some of which can be used as textile materials or as auxiliary materials applied to textile materials. Polyurethane stands out as a widely used polymer for coating textile products used in outdoor applications, because of high stability at low temperature, flexibility, no or very little volatile organic component content, high water resistance, pH stability, excellent solvent resistance, weather resistance, and many other chemical and mechanical properties. In the study, cotton, PET, and viscose fabrics were coated with polyurethane and aged under UV light to investigate the causes and behavior of the mechanical degradation effects of UV on the coating material and fiber. The results indicate that the PU coating process improves the mechanical properties of textile materials while being exposed to UV rays impair the fabric structure. The deterioration in the structure of raw and coated fabrics with the effect of UV increased the air permeability. According to the results of DSC analysis, the increase in the time of UV exposure did not create significant differences in terms of thermal degradation temperatures in both cotton and viscose fabrics. The glass transition temperatures (Tg) increased with more exposure to UV rays, and the UV exposure time had a negative effect on the melting temperature (Tm) and enthalpy (ΔH) of coated PET fabrics. [ABSTRACT FROM AUTHOR]

Co-melting paracetamol with different cellulose derivatives leads to full or partial amorphization of active substance. The aim of this study was to determine whether the amorphization of paracetamol after co-melting with cellulose derivatives is stable and whether it depends on the type of cellulose derivative added and the ratio of components. Mixtures of paracetamol with cellulose derivatives containing different proportions of components were prepared. Using differential scanning calorimetry (DSC), the samples were melted and the amorphization of paracetamol was confirmed. After 2 and 4 months, the samples were reanalyzed to determine the amorphization stability during storage and the difference in the effect of different polymers on the amorphization stability. The physical mixtures were additionally tested using Fourier transform infrared (FTIR) and Raman spectroscopic methods to confirm that no solid-phase interactions were noticed. Samples were also analyzed using ultrahigh-performance liquid chromatography (UHPLC) to assess the effect of co-melting and storage on the chemical stability of paracetamol. The results show that paracetamol amorphizes after co-melting with cellulose derivatives. The crystallization of paracetamol after co-melting depends on the polymer used and the proportions of the components. No interactions between the components and the chemical stability of paracetamol in the tested samples were confirmed.

Novel water-soluble complex polysaccharides (CPS) were obtained from Pteridium aquilinum and Dryopteris filix-mas. The yield of CPS was determined to be 4.161%-5.677%. As a result of the physicochemical composition, the CPS contained 12.10–13.65% moisture, 1.983–2.686% protein, 0.123–0.916% lipids and 12.06–21.52% ash. In HPLC analysis, sugar components of the samples (glucose+fructose+saccharose+maltose+lactose) ranged between 35.85–40.98%. Peaks of the fingerprint region specific for polysaccharides were identified during FT-IR analysis. DSC analysis showed that the glassy transition temperature of the DFR sample was higher than in the other three samples. A double cold crystallization peak was detected in all samples. During TGA analysis, the CPS samples exhibited a small amount of mass loss (1.2–1.85%) between 0 and 100 °C, and the DTGmax.p1 region continued up to 215–230 °C. These findings indicate that the four types of polysaccharides have excellent thermal stability (up to 230 °C) and are applicable to high-temperature food processing.

• Anti-leeches experimental activity using crude extracts of Niger seed hull (NSH). • Secondary metabolite identification of saponins, flavonoids, and terpenoids from methanol crude of NSH. • Pharmacokinetic model activities of methanolic extracted NSH has better time efficiency than chloroform extracted NSH to kill the leech parasite. In this work, crude extracts of Niger seed hull (NSH) were used to conduct anti-leech (Limnatis nilotica) experimental activity. Following the standard method, the phytochemical screening of methanol and chloroform extracts was evaluated. The crude methanol extract contained secondary metabolites as terpenoids, flavonoids, and saponins. According to severity effects ranging from 4+ to 1+ and timing zones from 1 to 720 min, including negative paralysis, the paralyzing time was calculated. From 1+ to 4+ severities, the crude extract of NSH exhibited strong anti-leech action. Methanol and chloroform extracts exhibit anti-leech properties that are comparable to the reference medication levaminsole. The dosage contraction of NSH in all dose levels of the standard reference drug Lavamisole resulted in a considerable death of leeches, as shown by the first-order reaction (χ2 = 62.9, df = 5, p < 0.05). The methanol and chloroform extracts of NSH significantly differed in how many leeches they were able to kill (χ2 = 355, df = 5, p < 0.05 and χ2 = 711.7, df = 5, p < 0.05, respectively). Differential canning calorimetry (DSC) was used to characterize the stability research of NSH crude extracts. Thermogram results revealed that four principal chemicals were valid in the 49.5 °C to 300 °C temperature range. According to a pharmacokinetic model, methanolic-extracted NSH kills the leech parasite more quickly than chloroform-extracted NSH. The current kinetic parameter results imply that methanol extract NSH has better anti-leech activity, and that it is a time-saving and environmentally acceptable organic chemical for future relevance to prevent anti-leech activity, and might be chosen for further research. [ABSTRACT FROM AUTHOR]

The article describes the modifying effect of methylcyclohexyldimethoxysilane (CH3)(cyclo‐C6H11)Si(OCH3)2 in propylene polymerization reactions with a pseudo‐homogeneous catalyst system: Ti(Oi‐C3H7)4‐Al(C2H5)2Cl/Mg(C4H9)2. This catalyst system is a convenient model for the analysis of modifier effects (effects of 'external donors') in supported Ziegler–Natta polymerization catalysts of the fourth generation. A combination of chromatographic, spectroscopic and calorimetric data for crystalline and amorphous fractions of polypropylene prepared in the presence of the silane shows that it has a dual modification effect: (i) the silane is a potent poison of stereo‐aspecific active centers in the catalyst (the centers producing amorphous polypropylene fraction) and (ii) silane molecules coordinate at isospecific centers in the catalyst and changes their nature: the centers produce isotactic polypropylene of higher molecular weight and a higher isotacticity level. © 2023 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Choosing the right phase change material (PCM) for a thermal energy storage (TES) application is a crucial step in guaranteeing the effectiveness of the system. Among a variety of PCMs available, the choice for a given application is established by several key factors, e.g., latent heat, stability, and melting point. However, phenomena such as subcooling—for which PCM cools in a liquid state below its solidification point—can lead to a reduction in the amount of energy stored or released, reducing the TES overall effectiveness, and also in some inaccuracies when modeling the problem. Thus, understanding the effects of subcooling on PCM performance is crucial for modeling and optimizing the design and the performance of TES systems. To this end, this work analyzes the PCM discharging phase in a cold thermal energy storage coupled to a chiller system. A first conduction-based predictive model is developed based on enthalpy–porosity formulation. Subcooling phenomena are encompassed through a control variable formulation, which takes its cue from the operation of a thermostat. Then, thermal properties of the PCM, i.e., the phase change range and specific heat capacity curve with temperature, are evaluated by using differential scanning calorimetry (DSC), in order to derive a second predictive model based on these new data, without including subcooling, for the sake of comparison with the first one. Experimental results from the storage tank confirm both model reliability and the fact that the PCM suffers from subcooling. Between the two numerical models developed, the first one that considers subcooling proves it is able to predict with satisfactory accuracy (RMSE < 1 °C) the temperature evolution on different tank levels. [ABSTRACT FROM AUTHOR]

BACKGROUND: Oleogels can be used in the food industry to reduce the consumption of solid fat in the human diet and diminish some of the industrial–technological issues of using oil instead of fat. Regarding the structural weakness of neat monoglyceride oleogel and the waxy mouthfeel of pure carnauba wax oleogel, as a result of the high melting and crystallization points, the present study aimed to diminish these defects. RESULTS: Carnauba wax (CBW) was used as a co‐gelator with distilled monoglyceride (DMG) at different weight ratios (100:0, 85:15, 70:30, 55:45, 40:60, and 0:100) (DMG: CBW) and two total gelator concentrations (50 and 100 g kg−1) to improve the DMG oleogel characteristics. The addition of CBW strengthened the DMG network and decreased the polymorphic transition. Thermal analysis showed just co‐crystallization at the 85:15 ratio, whereas, in the other combinations, high melting components of CBW crystalized at first. As a result of the crystal homogeneity and long‐time development, the oleogel properties improved at the 85:15 ratio. The low concentration of CBW and the formation of the eutectic system were efficient in the waxy mouthfeel reduction of oleogel at the 85:15 ratio in food applications. CONCLUSION: The DMG/CBW oleogel at the 85:15 ratio, with better structural and sensorial properties than DMG and CBW oleogels, respectively, has the potential for use instead of fat in food formulations. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Information on drug equilibrium solubility is crucial in producing a stable drug product, prolonging its shelf-life and maintaining its reported properties. Such data regarding the antipsychotic drug lurasidone hydrochloride (LRS HCl), were non-existent up to this date. We have presented results that could facilitate the formation of stable LRS HCl solid dispersions using amorphous poly(vinyl-pyrrolidone) (PVP) as a carrier. For the purpose of drug solubility enhancement, solid dispersions with different drug loads were prepared by solvent evaporation method and characterized by thermogravimetric analysis, differential scanning calorimetry, and Fourier-transform infrared spectroscopy (FT-IR). Thermal analysis has been used to detect the changes in heat capacity (cp) occuring upon formation of a binary drug-polymer solid dispersion. Thermodynamic model accounting for those cp changes is used to estimate the Gibbs free energy of mixing (GM) and thus the equilibrium solubility of LRS HCl in PVP solid dispersions. [ABSTRACT FROM AUTHOR]

This research aimed to evaluate the influence of the modified starch with octenyl succinic anhydride (MS) on anthocyanins content and the physical properties of the jaboticaba peel freeze‐dried powders. The formulations were obtained by mixtures of jaboticaba peel pulp and different MS content (10%, 15%, 20%, and 25%, w/w). The powders were characterized by physical properties, differential scanning calorimetry (DSC), infrared spectroscopy using the Fourier transform (FTIR), and anthocyanins content and retention by HPLC‐DAD. DSC analysis showed an increase in the glass transition temperature of the powders with an increase in the MS content (from −10.26°C to 53.40°C). Three anthocyanins were identified and quantified: delphinidin‐3‐O‐glucoside, cyanidin‐3‐O‐glucoside (main anthocyanin present in the samples), and peonidin‐3‐O‐glucoside. The retention of anthocyanins increased significantly with increasing MS content (from 18.0% to 58.0%). Overall, a positive effect of the MS content in the physical and physical–chemical characteristics of jaboticaba peel pulp powders could be observed. [ABSTRACT FROM AUTHOR]

This study explores the application of an Internet of Things (IoT)-driven reflectance-based multimode colorimeter for real-time monitoring of the crystallization process in oleogels-a novel class of structured lipids gaining popularity in the food industries. These structured lipids offer a healthier alternative to solid fats, but their texture and stability rely on precise control of crystallization process. Traditional monitoring methods, such as atomic force microscopy and spectroscopy, are expensive and lack real-time capabilities. The proposed device can operate in two modes: quality testing and process monitoring modes. In the quality testing mode, the device exhibits superior color accuracy compared to a commercial device, making it a reliable tool for color assessment (ΔE values < 10). In the process monitoring mode, the device effectively tracks crystallization kinetics at different incubation temperatures (5 °C, 15 °C, and 25 °C), revealing the impact of sunflower lecithin on primary and secondary crystallization phases. Further, the temperature vs. L* data offers more profound insights into oleogel crystallization, validated by Differential Scanning Calorimetry (DSC) analysis. Additionally, the device's performance was tested by monitoring the crystallization process of butter. The results obtained from the device closely matched the DSC findings, which enhanced our understanding of the crystallization processes in butter. This showcases the potential of the device for analyzing food samples. [Display omitted] • Development of an innovative IoT-driven reflectance colorimeter working in quality testing and process monitoring modes. • Quality Testing mode demonstrated better color accuracy compared to a commercial device. • In Process Monitoring mode, the device effectively tracked the crystallization kinetics of oleogels. • Strong positive correlations between the proposed device and DSC results validate its efficiency. • The testing of the developed device using butter sample is matched with the result obtained from DSC analysis. [ABSTRACT FROM AUTHOR]

The preparation of a hybrid containing arginine and Na montmorillonite (Na-Mt) was optimized by studying the effect of several parameters. The obtained samples were characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), and differential scanning calorimetry (DSC). These techniques approved the modification by the increase of the basal distance and the shift of the characteristic peaks of thermal analysis. The hybrid obtained in the optimal conditions was selected, incorporated in a graphite-based electrode, and tested in the analysis of the active molecule metronidazole (MTZ) by cyclic voltammetry (CV). The best electrochemical response was obtained in the conditions (pH = 9, CEC = 2, and stirring time = 12 h) and an optimum amount of hybrid was required in the electrode composition to have a well-defined cathodic peak corresponding to the reduction of MTZ. Results showed that the elaborated electrode reaction exhibits a diffusion-controlled process which is in agreement with several studies using other types of electrodes. [ABSTRACT FROM AUTHOR]

Biomass energy contributes nearly 14% of the total global energy. Therefore, biomass briquettes can be effectively considered an alternate source of fossil fuels. The present study aims at utilizing Senna auriculata and Ricinus communis waste generated locally for the production of biomass briquettes with 10% of tapioca starch as binder. The biomass wastes are blended at various proportions such as 0:100 (S1), 25:75 (S2), 50:50 (S3), 75:25 (S4) and 100:0 (S5) respectively, and the concentration of binder was maintained to be constant. The characterization of the prepared biomass briquettes includes the analysis of physical characteristics, proximate analysis, elemental analysis, SEM analysis, thermogravimetric analysis, differential scanning calorimetric analysis and XRD analysis. The results of the proximate analysis have revealed that the biomass briquettes possess lower percentage in terms of moisture content, ash content, sensible fixed carbon and high percentage of volatile matter content. Energy dispersive X-ray analysis has shown that the carbon and oxygen are the major elements for all the biomass briquettes. SEM analysis has revealed that the surface of the biomass briquettes is identified with irregular surface, lumps, cavities and few deposits of carbon particles. Thermogravimetric analysis and DSC analysis have reconfirmed the spontaneous burning characteristics of biomass briquettes. XRD analysis has proved that the bonding between each element present in the biomass briquettes is either monoclinic, tetragonal, orthorhombic or anorthic. [ABSTRACT FROM AUTHOR]

The paper presents the results of some research that aims to highlight the possible changes of the material deposited by 3D printing, when a hybrid heating source is used. The introduction of the second source produces changes in the deposited material, both from the point of view of the mechanical characteristics and from the point of view of the structure of the deposit. The use of an IR lamp to create a hybrid heating system produces a local increase in temperature between 28°C and 53°C, for distances between the IR lamp and the piece to print from 200 mm to 400 mm. This increase changes the height and width of the deposit, changes the state of the deposit surface making it less shiny, and changes the edges or limits of the holes, making them clearer. The visual testing and the DSC thermal analysis of the deposited material showed that the effects of these changes are positive, in terms of the decreasing of the discontinuities, and they are negative, in terms of the decreasing of the material plasticity. In conclusion, a hybrid heating during the FFF 3D printing process is possible; important is the appropriate dosage of the additional amount of heat. [ABSTRACT FROM AUTHOR]

A novel tri‐tetrapropylammonium dodeca bromobismuthate (III) compound has been synthesized and studied by single‐crystal X‐ray diffraction, differential scanning calorimetry, and Raman spectroscopy as a function of temperature. At room temperature, the title compound crystalizes in noncentrosymmetric Cc space group which belongs to monoclinic crystal system. The unit cell dimensions are a = 11.083(6) Å, b = 19.100(6) Å, c = 31.146(3) Å, β = 98.42(0)°, and V = 6522.69(9) Å3. The crystal package is provided by electrostatic interactions and hydrogen bonds (C–H ... Br). Intermolecular interactions present in the grown single crystal were analyzed by Hirshfeld surface and 2D fingerprint plot. The differential scanning calorimetry reveals two reversible phase transitions at 297 and 430 K. The values of the transition entropies suggest that the first is of an order–disorder type, while the second appears as a displacive one. The Raman versus temperature studies show that the vibrational states of tetrapropylammonium cations change markedly through the phase transitions. The most important changes are observed for two lines at 1034 and 1449 cm−1 (at room temperature) issued from the νs(N–C–C) + δs(C–N–C) and δs (CH3) of the cations. The spectral characteristics of these lines are analyzed and consistently described in the framework of an order–disorder model for the phase transitions. [ABSTRACT FROM AUTHOR]

In this work, differential scanning calorimetric (DSC) analyses were performed in an Ar inert medium in the temperature range of 100–750 K for the Y2O3 compound with the purity rate of 99.99%, the density in powder form is 0.069 g/cm3, the specific surface area is 100–150 m2/g, the particle size is in the range of 8–10 nm irradiated with fast neutrons with different intensities (E < 1  MeV). Using mathematical approximation methods, the equations of dependence of the heat flux function on temperature and heat capacity after irradiation at different intensities for the Y2O3 compound over a wide temperature range were determined. It was found that in the temperature range of 1 5 0 ≤ T ≤ 7 5 0  K, the value of the heat flux increases by 16.6%, up to 86 mW for the case of maximum radiation. At all radiation intensities, anomalies recorded with very small changes were observed in the spectra of the heat flux function related to the internal structural transitions. [ABSTRACT FROM AUTHOR]

Ever since the introduction of 3D printing, industries have seen an exponential growth in production and efficiency. Three-dimensional printing is the process of additive manufacturing (AM) in which the conventional method of material removal is challenged. Layer-on-layer deposition is the basic principle of the AM. Additive manufacturing technologies are used to create 3D-printed objects. An object is built in an additive technique by laying down successive layers of material until the object is complete. Each of these layers can be viewed as a cross-section of the item that has been lightly cut. When compared to traditional production methods, 3D printing allows the creation of complicated shapes with less material. In conventional methods, the materials go through several damages due to the tool–workpiece contact creating friction between them and the dissipated heat that damages the material. Overcoming the conventional method of machining with the help of 3D printing is a new advancement in the industries. The process involves using non-conventional methods for the machining of the parts. This research was oriented towards the chemical vapor jet drilling of the acrylonitrile–butadiene–styrene (ABS) materials. ABS materials are highly machinable and can be recycled for further usage. This paper focused on the usage of acetone as the chemical for drilling. The surface roughness and circularity of the drilled hole was taken into account for this research paper. We set up a manual experiment to run tests and get results. A vapor jet machine was designed with acetone as the core for the vapor. Various analyses were also formulated and conducted during experimentations. Surface roughness analysis provided the insight of roughness after the machining with the help of acetone vapor jet spray. SEM and micro-image parameters were also considered for more clear and advanced reports. In this research paper, DSC and FTIR analysis were performed to understand changes in the internal structure and the material properties of the ABS. Moreover, the research aimed to investigate the effect of various inputs processing parameters such as pressure, flow rate, and stand-off distance on the surface roughness and circularity of ABS workpiece material. The Taguchi L9 orthogonal array design was utilized to conduct tests by chemical vapor jet drilling using acetone and to evaluate the performance of the set-up while reducing the influence of interfering factors in order to provide reliable surface finish and circularity results. The results and conclusion of the research paper aimed to determine the most suitable parameters for the non-conventional acetone vapor jet drilling of the ABS material. The theoretical calculations predicted 1.64432 and 0.3289080 values of surface roughness and circularity, respectively. On the other hand, the experimental values were recorded as 1.598 for surface roughness and 0.322 for circularity. Therefore, a negligible error of 0.046 for surface roughness and 0.0031 for circularity, respectively, was noted which validate the statistical equations and the consistency of the combined vapor jet drilling process. [ABSTRACT FROM AUTHOR]

Heat curing epoxy‐based adhesives are extensively used in primary bonded structures. The manufacturing process of joints with heat curing adhesives is commonly made with isothermal processes where a large curing time is set to guarantee the complete curing of the adhesive. The aim of the current study is to investigate the influence of the curing state on the tensile mechanical properties of a structural one‐component epoxy based adhesive. To achieve this, tensile tests on bulk adhesive dog‐bone coupons with incomplete curing were performed. The process cycle was adjusted to achieve the desired curing degree for testing. The curing process was simulated by using the Kamal kinetics model calibrated with differential scanning calorimetry (DSC) tests. The results show that the curing process is very sensitive to the curing temperature, requiring a low curing temperature to control process duration. A good correlation between the estimated curing degree and the final obtained curing measured with the Fourier‐transform infrared spectroscopy FTIR was found. Regarding the mechanical properties, the elastic modulus and the tensile strength are reduced at lower curing degrees making the material softer and more ductile. The loss in the mechanical properties shows to be consistent with the measurements performed with dynamical mechanical analyses (DMA) by measuring the evolution of the elastic modulus with the curing degree. In this way, the numerical simulation of the curing process seems to be a valuable tool to predict the final performance of adhesive, and design the curing cycle. [ABSTRACT FROM AUTHOR]

In spite of increasing demands for rare-earth products, there are no enterprises in Russia that process natural raw materials and meet the needs of industry. The main amount of rare earth elements (REEs, >95%) is purchased abroad, while the unique Tomtor deposit is located on the territory of the Russian Federation, in which the REE content ranges from 15 to 40%. The phase transformations in the melts of the monazite–NaF system has been studied to obtain date to be used in the development of a technology for processing monazite raw materials and rare earth ores of the weathering crust of the Tomtor deposit. On melting the Tomtor monazite ores, two immiscible melts, namely, silicate and phosphate–salt ones, in which the REE concentration is up to 85%, form. According to its physicochemical properties, the phosphate–salt melt of segregation melting of the ore–NaF system is almost identical to the melt of the monazite–NaF system. In the melt of the monazite–NaF system, double phosphate (Na3Ln[PO4]2) and fluoride phosphate (Na2Ln[PO4]F2), which are easily dissolved in a weak solution of nitric acid, crystallize as a result of chemical reactions. REE oxalates and hydroxides are synthesized from nitrogen–phosphoric acid filtrates. [ABSTRACT FROM AUTHOR]

This paper discusses the results of the research carried out to study the structure, optical properties and thermophysical properties of a sample (nanopowder with a true density of 4.96 g/cm3, a particle size of 60 nm and a purity of 98.5%, SkySpring Nanomaterials, USA) with high purity. Based on the results of X-ray diffraction, the crystalline phase of MnFe2O4 ferrite nanoparticles was completely obtained and the values of the lattice parameters were determined. The results of the MID-IR analysis showed that the absorption coefficient (α) reaches its maximum value at 748 cm − 1 wave number. The optical properties of the as-prepared nanostructures were also investigated by VERTEX 70 V diffuse reflectance spectroscopy (DRS). As can be seen from the results of the DSC analysis, the effects occurring in the temperature range up to 3 0 0 ∘ C clearly reflect the nature of the phase transitions and the amount of energy generated in the ferrite samples. [ABSTRACT FROM AUTHOR]

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The carcinogenic effects and poor biodegradability of petroleum-based oils have pressurized the industry to develop eco-friendly lubricants. Nowadays vegetable oils are used as a potential base stock for industrial lubricants because of their excellent lubricating properties. Among the vegetable oils, rice bran oil is considered for this work due to its excellent frictional properties but the wear scar diameter generated was not comparable with that of industrial lubricants. These problems can be effectively solved by using suitable additives. Most of the commercially used additives are toxic and non-degradable. This research work focused to experimentally investigate the effect of bovine serum albumin (BSA) as a bio-molecular additive on the lubricant properties of rice bran oil (RBO). The lubrication mechanism of oil with bio-molecular protein additives is through the formation of an oil-protein layer between the surfaces, in which hydrophobic aggregates of the proteins adhere to the bounding surfaces and forms a secondary layer to improve the frictional and wear characteristics. The tribological, Physico-chemical, oxidation stability, and thermal properties of the modified rice bran oil were evaluated and compared with that of the base oil. The performance evaluation of the green cutting fluid formulated using modified RBO was also conducted and compared with that of the commercially available cutting fluid. The results obtained have indicated that the formulated oil-protein combination can be a potential base stock for bio-lubricants and bio-cutting fluids. [ABSTRACT FROM AUTHOR]

The crystal structure and thermal properties of the Ca 0. 5 In 1. 5 Se 3 compound have been investigated. Structural studies were performed by X-ray diffraction at room temperature. The crystal structure of this compound was found to correspond to the hexagonal symmetry of the space group P61. Thermal properties were studied using a differential scanning calorimetry (DSC). It was found in the temperature range 2 5 ∘ C ≤ T ≤ 9 5 0 ∘ C that thermal effects occur at temperatures T 1 = 1 0 2 ∘ C and T 2 = 8 4 8 ∘ C. The thermodynamic parameters of these effects are calculated. [ABSTRACT FROM AUTHOR]

Herein, we present a simple procedure for fabricating epoxy/graphite composites using a simple solution blending method. The addition of graphite filler in the epoxy matrix showed a beneficial effect on mechanical properties by enhancing Young's modulus up to 55.25% of its value. The highest thermal conductivity was obtained to be 1.53 ± 0.07 W· m−1· K−1, which depicts a fourfold increment as compared to the neat matrix. The effective thermal conductivity has been predicted using Nan model, which shows a satisfactory agreement with the experimental data. Besides, the investigated composites display enhanced electrical conductivity; this evolution of electrical conductivity as a function of filler volume fraction is well described using percolation theory. Thermogravimetry and differential scanning calorimetry have been used to determine the thermal properties of the composites as a function of filler volume fraction. These findings indicate that the thermal, electrical, and mechanical properties of epoxy/graphite composites could be ideal for thermal management and control of heat transfer devices. [ABSTRACT FROM AUTHOR]

Rapidly solidified (RS) binary Sn–5 wt.% Sb and ternary Sn–5 wt.% Sb– x wt.% Ag, x = 1, 3 and 5 solder alloys were prepared in form of ribbons using melt spinning technique (MS). X-ray diffractometer (XRD), scanning electron microscopy (SEM) attached with energy dispersive x-ray technique (EDX) and differential scanning calorimetry (DSC) were used to investigate the impacts of Ag contents on microstructures and properties of the binary Sn–5 wt.% Sb rapidly solidified alloy. XRD analysis confirmed the formation of an ultrafine microstructure of Ag3Sn intermetallic compound in addition to a supersaturated solid solution of Sn by Sb and Ag. Moreover, SEM and EDX analysis assigned the formation of SnSb intermetallic compound as well as the dissolution of Sb and Ag in β-Sn with maximum wt.% of 20.75 and 11.7 for Sn-5Sb and Sn-5Sb-5Ag ribbons, respectively. The melting point of the melt spun ribbons was lowered by 3.7 °C, 1.7 °C, 5.4 °C and 2.3 °C for the 0, 1, 3 and 5 Ag containing solder alloys as deduced by DSC. The rapidly solidified ribbons exhibit better Vickers hardness due to the microstructure refinements and the extension of solid solubilities of the alloying elements. [ABSTRACT FROM AUTHOR]

Two new metal coordination complexes, namely, poly[aqua(μ6‐benzene‐1,2,4,5‐tetracarboxylic acid‐κ8O1:O1,O2:O2′:O4:O4,O5:O5′)(μ‐but‐2‐enedioato‐κ2O1:O4)potassium(I)], [K2(C4H2O4)(C10H6O8)(H2O)2]n or [K2(fum)(H4btec)(H2O)2]n, (1), and poly[aqua(μ8‐2,5‐dicarboxybenzene‐1,4‐dicarboxylato‐κ12O1:O1′,O2:O2,O2′:O2′:O4:O4′,O5:O5,O5′:O5′)(μ‐ethanedioato‐κ4O1,O2:O1′,O2′)strontium(II)], [Sr2(C2O4)(C10H4O8)(H2O)2]n or [Sr2(ox)(H2btec)(H2O)2]n, (2) (H4btec = benzene‐1,2,4,5‐tetracarboxylic acid, H2btec = 2,5‐dicarboxybenzene‐1,4‐dicarboxylate, fum = fumarate and ox = oxalate), have been obtained under hydrothermal conditions by reacting the different alkali and alkaline earth metal salts with H4btec, fumaric acid (H2fum) and oxalic acid (H2ox). Complexes (1) and (2) were structurally characterized by single‐crystal X‐ray diffraction, IR and UV–Vis spectroscopy, powder X‐ray diffraction (PXRD) and thermogravimetic analysis–differential scanning calorimetry (TGA–DSC). Complex (1) displays a two‐dimensional (2D) layer with the K+ ion in a distorted pentagonal bipyramidal geometry and exhibits a uninodal 6‐connected hxl/Shubnikov plane net (3,6) with {36.46.53} topology. Complex (2) displays a three‐dimensional (3D) network structure, in which the Sr2+ ion is in a distorted monocapped square antiprism geometry. The framework possess a binodal (5,8)‐connected net with the Schläfli symbol {32.410.58.64.74}{32.46.52}2. The 3D Hirshfeld surfaces and 2D fingerprint plots show that the main interactions are the O...H/H...O intermolecular interactions. Moreover, the thermal decompositions of (1) and (2) in the temperature range 303–1273 K revealed that they both decompose in three steps and transform to the corresponding metal oxide. [ABSTRACT FROM AUTHOR]

This work aimed to obtain novel materials from malt modification for using in oil/water emulsions. Malt was modified using stearic acid (2% w/w) in combination with different energy densities (33.8 × 106, 60 × 106, 72.5 × 106, and 107.5 × 106 J/m3) from ultrasound probe resulting in four materials. These materials were characterized by degree of substitution (DS), amylose content, dextrose equivalent (DE), protein content, solubility, thermal properties, Fourier-transform infrared spectroscopy (FT-IR), crystallinity analysis by X-ray diffraction, and scanning electron microscopy. Emulsions containing 15% total solids (25% canola oil and 75% modified malt as stabilizing agent) were prepared and characterized. Results showed that increasing energy densities produced different effects on malt properties due to an increase in DS, amylose content, and DE values. The sonication process in combination with stearic acid increased malt solubility and the gelatinization temperature of malt, caused modifications of starch crystallinity in the amorphous region and hydrolysis of starch granules, and promoted good stabilizing properties for emulsions containing modified malt. [ABSTRACT FROM AUTHOR]

The ternary Ti(Oiso‐C3H7)4–Al2(C2H5)3Cl3/Mg(C4H9)2 catalyst polymerizes ethylene and copolymerizes it with 1‐hexene but does not polymerize propylene. The catalyst contains several types of active centers with different kinetic parameters; they produce polymer components with different average molecular weights. The centers have similar reactivities in ethylene/1‐hexene copolymerization reactions and produce copolymers with a relatively uniform compositional distribution. The catalyst can be used for synthesis of ethylene/1‐alkene copolymers of the linear low‐density polyethylene type. The principal advantages of the catalyst are high activity, stable kinetic behavior, low cost of all components and the ease of use: the catalyst is prepared in situ from three commercially available compounds readily soluble in aliphatic and aromatic hydrocarbons. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A novel Al–Si–Cu–Mg–Fe alloy was cast using gravity die casting and squeeze casting at low and high pressures. The micrographic analysis revealed significant variation in the grain size and phase morphologies. The high pressure employed in squeeze casting induced a compressive force on solidifying metal, which led to closure of the porosities resulting in the highest density and hardness. The differential scanning calorimetric analysis was performed from 480 to 650 °C, which demonstrated more stored energy and less amount of Al2Cu dissolution in the squeeze-cast samples. The high-pressure squeeze-cast alloy showed an enhanced strength and ductility of around 15% and 51%, respectively, than the conventional gravity casting due to grain refinement and a decrease in dendritic arm spacing. Wear resistance is highest for squeeze-casted samples at high pressure due to hard undissolved Al2Cu particles. [ABSTRACT FROM AUTHOR]

Energy valorization of empty fruit bunches (EFB), via torrefaction, was investigated to stablish the best process conditions and the energy balance of an integrated plant. Differential scanning calorimetry was used, for the first time, as a new and more accurate method to determine the heat involved in the torrefaction process. This technique showed that the torrefaction of EFB is an endothermal process. A new response variable energy gain (EG) was introduced as an alternative to the customarily used variable energy yield (EY). EG was definitely a better response variable because it makes a compromise between a high mass yield and a high heating values of the solid product. On the contrary, EY has a very strong and direct (lineal) correlation with the mass yield that overshadows the effect of the heating value. Results show that torrefaction is a promising technology for the sustainable valorization of EFB because it solves the disposal problem and gives a solid and renewable biofuel that can replace coal. Besides, an important amount of electricity can be co-produced. Energy balances showed that energy self-sufficiency can be achieved by tuning the torrefaction conditions as to obtain a gaseous by-product that is used as fuel to provide the energy required in the drying and torrefaction stages. Processing 100 ton/day of EFB (dry basis), at 300 °C and 60 min, produces 37 ton/day of bio-coal (similar to sub-bituminous coal) and 0.36 MW electricity that can be exported because the process is energy self- sufficient. [ABSTRACT FROM AUTHOR]

Effect of high molybdenum content ~10% as an alloying element on the strength and microstructural properties of 11% nickel—1.25% titanium maraging steel was evaluated. To increase the homogeneity and cleanliness of produced ingot, the investigated steel sample was produced by melting the raw material in an open-air induction melting furnace followed by refining utilizing a direct current electro-slag refining machine. The produced steel samples were both forged and heat-treated in optimum condition to acquire the full capacity of mechanical properties especially the tensile properties. After Forging and heat treatment at optimum condition, steel samples were evaluated by optical microscopy (OM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) analysis, electron backscattering diffraction (EBSD), and transmission electron microscopy (TEM). The experimental data showed that this steel sample has ultimate strength ~2100 MPa and elongation around 14%. High tensile properties obtained may be attributed on one hand due to the presence of high alloying lamellar martensite phase and lamellar austenite phase which has high dislocation intensity, and on the other hand, due to the high homogeneity and cleanliness of investigated samples from large nonmetallic inclusions. The results also show that a high amount of intermetallic compounds (NiMo3 and NiTi3) which are completely round and have a very low size not more than hundred nanometers.

The aim of this paper was to investigate the effects of wood flour on the mechanical, morphological and thermal properties of poly (L-lactic acid) (PLA)-chitosan biopolymer composites produced by compression molding. The composites were characterized by a combination of mechanical properties, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The addition of chitosan to PLA matrix reduced the tensile strength from 57.1 MPa for pure PLA to 34.3 MPa for 5% chitosan and 11.5 MPa for 10% chitosan, and the flexure strength from 72.3 MPa for pure PLLA to 30.4 MPa for 5% chitosan and 24.6 MPa for 10% chitosan. The change trend in the young’s modulus was found to be similar as compare with the tensile strength. However, the flexure modulus generally increased with the addition of the chitosan as comparison with pure PLA. The mechanical properties of the PLA-chitosan blends with wood flour were found to be lower than theirs of the pure PLA. According to SEM images, some holes and small voids at various diameters on the fractured section of the all composites were seen. Tonset, T10%, T50%, T85% of the pure PLA decreased with the addition of both chitosan and wood flour. Thermal stability of the PLA-chitosan blends was determined to be better than the PLA-chitosan composites with wood flour.

The polylactic acid (PLA) resin Ingeo 4032D was selected as the research object. Epoxy soybean oil (ESO) and zeolite (3A molecular sieve) were used as plasticizer and reinforcing filler, respectively, for PLA blend modification. The mixture was granulated in an extruder and then blown to obtain films under different conditions to determine the optimum processing temperatures and screw rotation. Then, the thermal behaviour, crystallinity, optical transparency, micro phase structure and physical properties of the film were investigated. The results showed that with increasing zeolite content, the crystallization behaviour of PLA changed, and the haze of the film increased from 5% to 40% compared to the pure PLA film. Zeolite and ESO dispersed in the PLA matrix played a role in toughening and strengthening. The PLA/8 wt% zeolite/3 wt% ESO film had the highest longitudinal tensile strength at 77 MPa. The PLA/2 wt% zeolite/3 wt% ESO film had the highest longitudinal elongation at 13%. The physical properties depended heavily on the dispersion of zeolite and ESO in the matrix.

In the present study, the microstructural features and its correlation with mechanical properties of modified strain-induced melt activation (modified SIMA) processed Al- (7, 12, 14 wt-%) Si alloys are investigated. The microstructure of modified SIMA process Al–Si alloys consists of globular α-Al grains, primary Si particles and Al–Si eutectic phase. The casting defects and surface roughness are minimised and the morphology of eutectic silicon is modified after modified SIMA treatment. The mechanical properties of modified SIMA processed samples are increased significantly as compare to as-cast alloy due to reduction of porosity, formation of fine globular microstructu+re and accumulation of high dislocation tangle near primary Si particles. [ABSTRACT FROM AUTHOR]

Solid–liquid-phase equilibrium is an important part of chemical thermodynamics, and its basic theoretical research plays a vital role in the advancement of the chemical industry. Solid–liquid equilibria for binary mixtures of 3-nitrotoluene and 4-nitrotoluene were measured using differential scanning calorimetry under atmospheric pressure (101.3 kPa). The results showed that the phase diagram of the 3-nitrotoluene + 4-nitrotoluene binary system presented a eutectic behavior, and the eutectic point was x1 = 0.6487, TE = 272.15 K. Furthermore, the experimental results were correlated with Wilson and nonrandom two-liquid (NRTL) activity coefficient models well. The relative standard deviations were 0.496 and 0.236, respectively, and the absolute mean deviations were 0.005 and 0.001, respectively. [ABSTRACT FROM AUTHOR]

The aim of this paper was to investigate the effects of wood flour on the mechanical, morphological and thermal properties of poly (L-lactic acid) (PLA)-chitosan biopolymer composites produced by compression molding. The composites were characterized by a combination of mechanical properties, scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The addition of chitosan to PLA matrix reduced the tensile strength from 57,1 MPa for pure PLA to 34,3 MPa for 5% chitosan and 11,5 MPa for 10% chitosan, and the flexure strength from 72,3 MPa for pure PLLA to 30,4 MPa for 5% chitosan and 24,6 MPa for 10% chitosan. The change trend in the young's modulus was found to be similar as compare with the tensile strength. However, the flexure modulus generally increased with the addition of the chitosan as comparison with pure PLA. The mechanical properties of the PLA-chitosan blends with wood flour were found to be lower than theirs of the pure PLA. According to SEM images, some holes and small voids at various diameters on the fractured section of the all composites were seen. Tonset, T10%, T50%, T85% of the pure PLA decreased with the addition of both chitosan and wood flour. Thermal stability of the PLA-chitosan blends was determined to be better than the PLA-chitosan composites with wood flour. [ABSTRACT FROM AUTHOR]

The DNA/RNA-binding KIN protein was discovered in 1989, and since then, it has been found to participate in several processes, e.g., as a transcription factor in bacteria, yeasts, and plants, in immunoglobulin isotype switching, and in the repair and resolution of double-strand breaks caused by ionizing radiation. However, the complete three-dimensional structure and biophysical properties of KIN remain important information for clarifying its function and to help elucidate mechanisms associated with it not yet completely understood. The present study provides data on phylogenetic analyses of the different domains, as well as a biophysical characterization of the human KIN protein (HSAKIN) using bioinformatics techniques, circular dichroism spectroscopy, and differential scanning calorimetry to estimate the composition of secondary structure elements; further studies were performed to determine the biophysical parameters ΔHm and Tm. The phylogenetic analysis indicated that the zinc-finger and winged helix domains are highly conserved in KIN, with mean identity of 90.37% and 65.36%, respectively. The KOW motif was conserved only among the higher eukaryotes, indicating that this motif emerged later on the evolutionary timescale. HSAKIN has more than 50% of its secondary structure composed by random coil and β-turns. The highest values of ΔHm and Tm were found at pH 7.4 suggesting a stable structure at physiological conditions. The characteristics found for HSAKIN are primarily due to its relatively low composition of α-helices and β-strands, making up less than half of the protein structure. [ABSTRACT FROM AUTHOR]

This study investigated the effects of adding Zr, as a base alloying element, besides Ni and Mn in different amounts and combinations on the melting and solidification characteristics of 354-type Al-Si-Cu-Mg alloys. Differential scanning calorimetry (DSC) was used to characterise the sequence of reactions occurring during the heating and/or cooling cycles; whereas scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) techniques were used to observe and identify existing intermetallic phases. Nickel proved to have a retarding effect on the kinetics of precipitation of the α-Al network and the eutectic Al-Si structure. Also, the presence of Ni consumed a considerable amount of Cu to form Al-Cu-Ni particles instead of Al2Cu particles. Results revealed that solution treatment at 495°C for 5 h was sufficient to dissolve a large amount of Al2Cu particles in the α-Al matrix, which is mandatory for a successful aging treatment of the alloys studied. Additions of these transition elements produced new intermetallic phases such as (Al,Si)3(Ti,Zr), (Al,Si)3Zr, Al9FeNi, Al3Ni, Al3CuNi, and Al9FeSi3Ni4Zr, in addition to the other phases, namely α-Al, eutectic silicon, Al2Cu, Mg2Si, Q-phase (Al5Cu2Mg8Si6), commonly observed in 354-type alloys, and Fe-based intermetallic phases including β-Al5FeSi, α-Al15(Fe, Mn)3Si2, and π-Al8FeMg3Si6. Superheating the melt at 800°C instead of 750°C had an advantageous effect in that Al3Zr particles originating from the Al-15%Zr master alloy were dissolved and hence coarse Zr-containing particles were barely spotted in the microstructures examined. [ABSTRACT FROM AUTHOR]

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A chemical reaction mechanism is proposed to describe the pyrolysis of scrap tire rubber based on the decomposition of their three main polymer compounds (natural, butadiene and styrene-butadiene rubbers). Samples of each polymer were tested separately using differential scanning calorimetry (DSC) at the same operating conditions (heating rate, temperature and atmosphere). The thermograms clearly show that the polymer decomposition takes place in two or three thermal steps. The comparison with the literature allowed associating these steps with depolymerization reactions. The DSC results also allowed determining the kinetic parameters for each reaction considered in the chemical mechanism proposed in this study. Consequently, these were included in a mathematical model developed for a fixed bed reactor (at laboratory-scale) considering mass and energy balances. The experimental conversion obtained in TGA at operating conditions of pyrolysis using scrap tire rubber as feedstock, were successful confronted with those simulated by the mathematical model obtaining a determination coefficient (R2) of 0.97. On the other hand, the mathematical model predicts correctly the influence of the temperature in the product yields, being this variable the most statistically significant in the process, being in agreement with ANOVA results ((p value < 0.001 at confidence level of 95%) allowing a good prediction of the product yields. [ABSTRACT FROM AUTHOR]

This paper aims to understand the influence of microalloying constituents (Ti, Zr, Sr and Sc), and three heat treatment conditions i.e., T6, retrogression and reaging (RRA) and high temperature aging (HTA) on mechanical and thermal characteristics of modified Al-Zn-Mg-Cu-X alloy using microstructural analyses consist of precipitation characteristics, phase fraction and phase morphology. Addition of 0.25 wt % Sc significantly refines the grain structure, reducing the grain size from 62 μm to 34 μm and increasing Al 3 Zr, Al 3 (Zr, Ti), and Al 3 (Sc, Zr) precipitate fraction. After T6 aging, the alloy exhibits primary precipitates of fine η and T phases, accompanied by secondary intermetallics as well as S phases. RRA treatment led to a slightly larger fraction of coarse Zn and Cu-rich phases, while HTA results in larger η, T, and S phases due to high-temperature aging. The addition of Sc reduces the cooling rate by raising the transition temperature to 532 °C with an enthalpy of 22.1 J/g. T6 treatment shows dissolution of most η phases within the matrix, although RRA and HTA exhibit higher enthalpy due to a greater fraction of η phases. The tensile strength of Al-Zn-Mg-Cu-X alloy follows the following sequence: T6 > RRA > HTA > as-cast condition, regardless of micro-alloy additions. Under T6 conditions, Sc added alloy achieves 30 % higher strength, i.e., 575 MPa, than base alloy due to fine dispersoids. RRA treatment enhances elongation without compromising mechanical properties, resulting in a shift from transgranular brittle fracture to intergranular-dominated mix-mode fracture, with the presence of secondary cracking. [Display omitted] • Sc addition refines grains, reduces size to 34 μm, increases Al 3 M precipitates. • T6 treatment shows primary η and T phases with secondary intermetallics. • Sc addition raises transition temp to 532 °C, decreases cooling rate with enthalpy of 22.1 J/g. • T6 dissolves most η phases, RRA and HTA have higher enthalpy due to increased η fraction. • Sc-added alloy achieves 28 % higher strength due to fine dispersoids; RRA enhances elongation. [ABSTRACT FROM AUTHOR]