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Herein, the nanofibrillated poly(butylene succinate)/polytetrafluoroethylene (PBS/PTFE) composites were prepared. The relaxation time was prolonged by PTFE fibrils, resulting in an enhancement in storage modulus and melt viscosity. Differential scanning calorimetry was used to study the non-isothermal crystallization kinetics at different cooling rates. These results showed that PTFE fibrils could promote crystallization nucleation and excessive fibrils could inhibit crystallization growth. Lightweight PBS/PTFE composite foams were fabricated using core-back foam injection molding. Loading the PTFE fibrils increased the cell density of PBS foam from 2.7×106 to 1.4×108 cells/cm3 and improved the cell morphology of PBS foam. By controlling the foaming parameter, the tensile properties of PBS-based composite foam with 1 wt.% PTFE were improved overall, and the Izod impact strength was increased by 9–69% compared with the PBS foam. [ABSTRACT FROM AUTHOR]

Fe-based amorphous alloys are an eco-friendly alternative to Ni- and Co-based amorphous alloys, which are not sustainable. Herein, amorphous Fe–P alloys were electrodeposited from an eco-friendly aqueous electrolyte. The influence of bath temperature on the electrochemical behaviour during Fe–P alloy deposition was investigated using linear-sweep voltammetry, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry. The morphology, P content and phase structure were characterized via scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction and differential scanning calorimetry. The electrochemical corrosion behaviour in 3.5 wt% NaCl solution was studied using potentiodynamic polarization curves and EIS spectra. The results showed that an increase in bath temperature leads to a positive shift in the inductive co-deposition potential and increases the reaction rate. At bath temperatures of 20–60°C, the P content in deposits varied in the range of 17.07–21.13 wt% and the phase structure was amorphous. Although the amorphous alloys lacked crystalline defects, the P content had a marginal effect on the corrosion properties, whereas the surface morphology significantly influenced the corrosion properties. The amorphous Fe–P alloys fabricated in this study exhibit superior corrosion properties to almost all electrodeposited amorphous alloys reported in the literature, demonstrating their potential for corrosion protection. [ABSTRACT FROM AUTHOR]

Cyclosporine A (CyA) holds significant importance as a strategic immunosuppressive drug for organ transplant patients. In this study, we aimed to produce pure and cost-effective Cyclosporine A (CyA) by fermenting a culture medium containing dairy sludge, using Tolypocladium inflatum PTCC 5253. Following the fermentation stage, ethyl acetate extraction and fast protein liquid chromatography were employed for sample purification. The initial evaluation of the effectiveness of CyA obtained from these processes was performed through bioassay, wherein the antimicrobial clear zone diameter was found to be larger compared to the sample obtained from the fermentation culture. The concentration of CyA was determined using high-performance liquid chromatography, yielding values of 334 mg/L, 456 mg/L, and 578 mg/L for the fermented, extracted, and purified samples, respectively. Further analysis utilizing liquid chromatography tandem mass spectrometry (LC/MS/MS) confirmed a purity of 91.9% and proper agreement with the standard sample based on the ion intensity of Z/m 1205. To validate the structure of CyA, nuclear magnetic resonance spectroscopy, Fourier-transform infrared (FT-IR), and Raman spectroscopy were employed. X-ray diffraction and differential scanning calorimetry analyses demonstrated that the purified CyA exhibited a crystal structure similar to the standard sample, characterized by two broad peaks at 2θ = 9° and 20°, and comparable glass transition temperatures (57–68 °C for the purified sample; 53–64 °C for the standard sample). Dynamic light scattering analysis confirmed a uniform particle size distribution in both the purified and standard samples. The zeta potentials of the purified and standard samples were determined to be − 25.8 ± 0.16 and − 23.63 ± 0.12 mV, respectively. Our results demonstrate that dairy sludge can serve as a suitable culture medium for the production of (CyA). [ABSTRACT FROM AUTHOR]

Although a low temperature limit for life has not been established, it is thought that there exists a physical limit imposed by the onset of intracellular vitrification, typically occurring at ~−20 °C for unicellular organisms. Here, we show, through differential scanning calorimetry, that molar concentrations of magnesium perchlorate can depress the intracellular vitrification point of Bacillus subtilis cells to temperatures much lower than those previously reported. At 2.5 M Mg(ClO4)2, the peak vitrification temperature was lowered to −83 °C. Our results show that inorganic eutectic salts can in principle maintain liquid water in cells at much lower temperatures than those previously claimed as a lower limit to life, raising the prospects of active biochemical processes in low temperature natural settings. Our results may have implications for the habitability of Mars, where perchlorate salts are pervasive and potentially other terrestrial and extraterrestrial, cryosphere environments. A differential scanning calorimetry study of Bacillus subtilis vitrification shows that perchlorate salts can lower the onset of intracellular vitrification, with implications for the low temperature limit of life in salt-rich subzero environments. [ABSTRACT FROM AUTHOR]

A familiar polyalcohol, 1,2-propanediol (12PDO), is among the simple alcoholic solvents with high solubility for lithium tetrafluoroborate (LiBF4), as well as a wide temperature range for liquids. The viscosity of 12PDO solutions containing LiBF4 was measured in the temperature range of 280‒340 K using a vibrational viscometer, and it exhibited non-Arrhenius behavior fitted with the Vogel–Fulcher–Tamman (VFT) equation, which is an empirical model for describing liquid dynamics. The viscosity (η) increased with the increasing mole fraction of LiBF4 (x), and the variation in η was found to be mainly controlled by the pre-exponential factor η0 in the VFT expression. The VFT-fitting parameters, the strength parameter (D), and ideal glass transition temperature (T0), which indicate the Arrhenius behavior and an ideal glass transition temperature, respectively, correlated with the thermal analysis results that were obtained via differential scanning calorimetry. With the increasing x, the value of D decreased rapidly for x < 0.20, whereas it remained approximately unchanged for x > 0.20. The concentration dependence of T0 also differed at approximately x = 0.20. The changes in D and T0 with x indicated that the intrinsic hydrogen-bonding networks between the solvent molecules were rapidly destroyed by the added ions at reduced salt concentrations, while such a structural breaking effect of the added ions weakened owing to ion associations at increased salt concentrations. Thus, it was observed that the solvation structure and dynamics of the solutions strongly depended on the salt concentration. [ABSTRACT FROM AUTHOR]

The main theme of the paper was focussed on the preparation, structural, optical, and photoluminescence studuies of p(-n-decyloxy) benzoic acid (10OBA) liquid crystalline (LC) compounds with 1 wt.% dispersed ZnO nanoparticles (NPs). The prepared samples were subsequently characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), optical polarizing microscopy (POM), differential scanning calorimetry (DSC), UV-Visible spectroscopy, and photoluminescence (PL) studies. From the XRD, the diffraction peaks observed at 36.2, 42.5, 61.3, and 73.2° were well resolved, indicating the presence of ZnO NPs and the particle size was found to be 65 nm. SEM studies revealed the uniform dispersion and the presence of ZnO NPs in the samples. The textural images of different phases (nematic, smectic) of liquid crystalline compounds of 10OBA pure and 10OBA with 1 wt.% dispersed ZnO NPs were observed through the POM with reduced temperature. From the DSC thermograms, the phase transition temperatures and the correponding enthalpy values were estimated. The bandgap reduces for 10OBA LC compound with the dispersion of 1 wt.% ZnO NPS and it is estimated as 3.25 eV compared with 4.25 eV for the undoped 10OBA LC compound. PL studies showed the presence of the peak at 616 nm owing to the presence of point defects within the bandgap-like vacancies and interstitials known as deep-level emission. [ABSTRACT FROM AUTHOR]

In this work, effect of varying lithium perchlorate (LiClO4) salt concentration in polymer gel electrolytes (PGE) containing heat resistant polymethyl methacrylate (PMMA), and succinonitrile (SN) is investigated via electrochemical and physical properties. The electrolyte specimen with high LiClO4 salt concentration of 1.5 M supports maximum ionic conductivity of 4.9 × 10–5 S cm−1 and electrochemical stability window of ~ 4 V. The ion-transport parameters evaluated from the tangent loss studies confirms that the optimized electrolyte possesses diffusivity (D) of 4.52 × 10–2, mobility (μ) of 1.746 cm2 V−1 s−1, number of charge carriers (N) of 1.78 × 1014 cm−3 and Nµ of 3.106 × 1014 cm−1 V−1 s−1. The dielectric constant studies show that the optimized electrolyte possesses maximum dielectric constant and lower value of modulus towards the high frequency region. The thermogravimetric and differential scanning calorimetry studies confirms that the prepared electrolytes offer weight loss of < 9% up to 373 K and maintains the gel phase up to 570 K, respectively. X-ray diffraction suggest that the PGE system becomes more amorphous with progressive addition of LiClO4 up to 1.5 M, while the Fourier transform Infra-red (FTIR) spectroscopy study reveal the salt-polymer interactions. [ABSTRACT FROM AUTHOR]

2,6-Di-tert-butyl-4-methylphenol (BHT) is an excellent antioxidant that is easily oxidized to 2,6-di-tert-butyl-4-hydroperoxyl-4-methyl-2,5-cyclohexadienone (BHTOOH). For the safety of BHT production and usage, it is meaningful to study the thermal stability and decomposition properties of BHT and BHTOOH. In this paper, the thermal decomposition properties of BHT and BHTOOH were compared by the mini closed pressure vessel test (MCPVT) and differential scanning calorimetry (DSC). Their kinetics of thermal decomposition were studied using thermogravimetric analysis (TGA). The thermal decomposition products of BHT and BHTOOH were analyzed by gas chromatography-mass spectrometry (GC–MS). The results show that there was no significant change in temperature pressure when BHT was warmed up under a nitrogen atmosphere, indicating that BHT was stable within 400 K. The thermal decomposition reaction of BHTOOH was rapid with an initial reaction temperature of 375.2 K. The initial exothermic temperature (Ti) and heat release (QDSC) of DSC were 384.9 K and 865.0 J g−1, respectively. The apparent activation energies (Ea) for the thermal decomposition reactions of BHT and BHTOOH calculated by the Kissinger method were 151.8 kJ mol−1 and 66.07 kJ mol−1, respectively. The main decomposition products of BHT were isobutene and 2-tert-butyl-4-methylphenol. The thermal decomposition products of BHTOOH included BHT, 2,6-di-tert-butyl-4-ethylphenol, 3,5-di-tert-butyl-4-hydroxybenzaldehyde, 4,4′-(1,2-ethanediyl) bis [2,6-bis (1,1-dimethylethyl) phenol, etc. Based on the thermal decomposition behavior and products, the reaction pathway has been described. These results indicate that BHT is a potential thermal hazard during production, storage and application. For the safety of the chemical industry, the oxidation of BHT should be avoided. [ABSTRACT FROM AUTHOR]

Bio-based coating materials have received increased attention because of their low-cost, environmentally friendly, and sustainable properties. In this paper, a novel coating material was developed to coat ureas using bio-based coating material derived from liquefied eggplant branches to form controlled-release ureas (CRUs). Also, the optimum proportion of liquefier was studied. Furthermore, dimethyl siloxane was used to modify liquified eggplant branches to make them hydrophobic, resulting in hydrophobic controlled-release ureas (SCRUs). This hydrophobic-enabled coating is environmentally friendly and highly efficient. The products were characterized by specific scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry, and the water contact angles of CRUs and SCRUs were determined. The nutrient-release characteristics of the SCRUs in water were determined at 25 °C and compared with those of CRUs. The results showed that the modification with dimethyl siloxane reduced the N release rate and increased the longevity of the fertilizer coated with hydrophobic bio-based coating material. In addition, organosilicon atoms on the SCRU surface also block the micro-holes on the coating and thus reduce the entry of water onto the coating. The results suggest that the new coating technology can create a hydrophobic surface on bio-based coating material and thus improve their controlled-release characteristics. [ABSTRACT FROM AUTHOR]

The present study displays a comprehensive investigation into the micro- and macrostructures of gluten and its responses to temperature-induced changes, employing various analytical techniques. The integration of time domain-nuclear magnetic resonance (TD-NMR), differential scanning calorimetry (DSC), size-exclusion high-performance liquid chromatography (SE-HPLC), field emission scanning electron microscopy (FESEM), solid-state nuclear magnetic resonance (ssNMR), and multiphoton laser microscopy (MLM) measurements facilitates the multidimensional examination of gluten's phase distribution and structure across various scales. Notably, TD-NMR helps to refine prior T2 assignments for hydrated gluten through dynamic T2 measurements at sub-zero temperatures. The innovative application of TD-NMR uncovers insights into freezable water quantities and their changes under varying temperature conditions. Through real-time analyses utilizing not only TD-NMR but also MLM techniques, along with SE-HPLC measurements, the study highlights increased lacunarities in the gluten structure, particularly between 60 and 85 °C. These structural changes are attributed to heating effects that unfold and denature proteins and culminate in aggregation and crosslinking phenomena, leading to the release of water into macropores, hence changes in the water distribution in the gluten matrix. [ABSTRACT FROM AUTHOR]

Background: Niosomes hold promise as drug delivery systems for cancer treatment, with niosome size impacting stability, biodistribution, and effectiveness. This study optimized methotrexate (MTX)-loaded niosome formulation by studying the effects of components and processing conditions on size. The niosomes formulation was made by the thin-film hydration technique. Results: The optimized formulation (NIO 17) with a 6:2:2 ratio of span 60, soya PC, and cholesterol achieved 55.05% methotrexate encapsulation, particle size 597.2 nm, PDI 0.49, and zeta potential − 23.3 mV. The compatibility of methotrexate with lipids was confirmed via Fourier transform infrared spectroscopy, and transmission electron microscopy revealed spherical, well-dispersed vesicles. Differential scanning calorimetry indicated methotrexate conversion or entrapment within vesicles. In vitro release exhibited a sustained pattern with an initial burst. NIO 17 showed potent anti-cancer activity against B16-F10 cells (GI50: 38.7176 μg/mL). Ex vivo studies suggest tailoring niosome size (597.2–982.3 nm) to target specific skin depths (0–38 μm) for enhanced localized drug delivery. Conclusions: This study demonstrates the potential of methotrexate-loaded niosomes as a novel cancer therapy approach, highlighting the potent anti-cancer activity and transdermal delivery potential of NIO 17. Further research is necessary to explore its clinical translation. [ABSTRACT FROM AUTHOR]

Due to their outstanding chemical and physical properties, polyimides are widely used in industrial applications. The degree of imidization of polyimides significantly influences their properties, making it an important factor in tailoring the material for specific applications. Imidization refers to the process of converting a precursor poly(amic acid) by removing water, and it is essential to analyze this process in detail to tune the final structure and properties of the material. Conventional techniques for this task include Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), or differential scanning calorimetry (DSC), but they lack the possibility of spatially and/or depth-resolved analysis or do not enable in-line monitoring capabilities. To overcome these limitations, we propose laser-induced breakdown spectroscopy (LIBS) as a powerful tool for the monitoring of the imidization reaction. To establish a measurement method, a total of 130 in-house prepared, self-synthesized samples were thermally cured to exhibit varying imidization degrees. IR spectroscopy served as a reference technique during method development, and a novel formula for calculating the degree of imidization, based on the C2 and H signal trends, was introduced. The calculated imidization degrees of model thin films based on LIBS were in good accordance with the IR reference method although minor differences between the two methods were expected due to varying information depth and the size of the sampled area. Additionally, the robustness of the procedure was demonstrated by depth profiling of a stacked model polymer, spiking with commercially available additives and, ultimately, by analyzing industry-relevant polymer samples. [ABSTRACT FROM AUTHOR]

In the world practice, the organic carbon content (Corg) in the soils containing carbonates is measured in different ways. We have analyzed the methods for solving this problem including the state-of-the-art approaches, such as thermogravimetry, differential scanning calorimetry, and spectroscopy. As is shown, the presence of CaCO3 does not prevent the Corg measurement with dichromatometric method (Tyurin and Walkley–Black variants). The disadvantages of this method comprise the laborious analysis, constant presence of operator, incomplete oxidation of organic compounds, and environmental pollution. The measurement of soil weight loss-on-ignition (LOI) is economical and rapid but overestimates Corg content because of inadequacy of the conversion factor of 1.724, the presence of adsorbed and chemically bound water, as well as mineral components decomposing at T = 105–550°C. The most relevant solution for assaying the Corg content in carbonate soils is to use an analyzer and a calcimeter although the accuracy of Corg measurements in the presence of carbonates is significantly reduced because the errors of two methods are quadratically summed. A high cost of the device, maintenance, verification, and repair limit its widespread use in soil laboratories. The content of soil carbonates can be measured using both gravimetric (LOI) and volumetric (calcimeter) methods. The latter method is preferable for the soils with the prevalence of CaCO3 in carbonates. The preliminary removal of carbonates from soil samples is labor-intensive and can cause a partial loss of Corg via acid extraction. A high cost of the instruments and the absence of the libraries of soil spectra hinder the development of Vis-NIR and MIR spectroscopy as an alternative to wet chemistry methods. Further comparative studies will give a deeper insight into the spatial patterns in the distribution of soil organic carbon. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is a type of cancer that affects the colon or rectum and occurs in individuals over the age of 50, although it can affect people of all ages. Quercetin is a flavonoid, which is a type of plant pigment with antioxidant and anti-inflammatory properties. Some studies have explored the potential of quercetin as an adjuvant therapy to enhance the effectiveness of chemotherapy or radiation therapy. Methodology: In the proposed work, the nano-biomaterials of solid lipids such as stearic acid (SA) and tripalmitin (TpN) as well as the surfactants tween 80 and span 80 were used to prepare novel quercetin (QuR)-loaded-solid lipid nanoparticles (QuR-SLNs) for medical applications in colorectal cancer (CRC). The resulting bio-nano SLNs' mean entrapment efficiency (EE) and particle size (PS) were optimized by Box–Behnken design (BBD) approach based on the response-like surface methodology (RSM). The variables include lipid ratio (X1), surfactant ratio (X2), QuR-to-lipid ratio (X3), the sonication time (X4), and the homogenization time (X5). Requirements on the maximum EE (%) and minimum PS (nm) were optimized for the preparation of QuR-SLN. Differential scanning calorimetry (DSC), X-ray diffraction (XRD) analysis, and scanning electron microscopy (SEM) were then used to analyze the optimized SLN and to find the crystalline state of QuR with lipid relationship. In addition, on the Caco-2 cells, at IC50 (49 µM/mL), in vitro cytotoxicity was attained. Results: The optimized QuR-SLN had practically spherical shapes, with % EE and a PS of 97.8 ± 1.16% and 132.16 ± 4.1 nm, respectively. In aqueous media, the degree of lipid crystallinity and the lipid modification was investigated, and the QuR incorporation and release patterns showed high correlations with both. The results showed that over 41.12 ± 1.6% of the bio-nano QuR-SLNs was released gradually over the course of 48 h, demonstrating effective QuR delayed release. Results on apoptotic observations indicate that apoptosis accounts for the majority of cell death, while necrosis, a type of cell death, constitutes a very minor portion. In conclusion, the prepared bio-nano QuR-SLNs might improve cytotoxicity and can act as an ideal carrier for the delivery of QuR and this preparation is used in the treatment of CRC. [ABSTRACT FROM AUTHOR]

This work presents the application of L-tartaric acid (L-TA), ascorbic acid (AA), and L-carnitine (L-CAR) as a safe and non-toxic alternative agent to enhance the aqueous solubility of baclofen (BAC). The solvent evaporation method was employed for co-crystallization in three stoichiometric ratios of the drug, coformer (1:1, 1:3, 1:5) and formulations were confirmed by X-ray diffractometry (XRD), differential scanning calorimetry (DSC), and Fourier transform infrared (FT-IR). DSC study revealed the presence of both endothermic and exothermic peaks in compounds containing AA and L-TA. With respect to the BAC, L-TA and BAC, AA, the appearance of new diffraction peaks that do not overlap with un-processed BAC may be the implication of a new structure. The intensity of some diffraction peaks disappeared or reduced significantly which may also imply the formation of a new crystal phase. The solubility of the multicomponents increased and surpassed the solubility of BAC. Overall, the new compounds show significantly higher drug solubility whereas their physical mixtures only demonstrate a marginal increase in BAC solubility. The high solubility records of BAC, AA and BAC, L-TA evidence the marked difference in solubility of the new compounds with respect to their physical mixtures. The saturation solubility of BAC, L-CAR compound did not show any improvement relative to the un-processed BAC. These findings confirm that a new crystal phase may not have been obtained during the co-crystallization of BAC and L-CAR. [ABSTRACT FROM AUTHOR]

Sustainable polymer composites (or biocomposites) based on renewable and green polymers are progressively under development in a technological paradigm shift from "just use more and more" to "convert into value-added products". Therefore, significant efforts should focus not only on their reduced environmental impact but also on maximizing their performance and broadening their application range. Herein, the bio-based blends based on Mater-Bi bio-plastic and poly(ε-caprolactone), at a weight ratio of 70:30, were developed, followed by the addition of UFC100 cellulose filler to yield sustainable biocomposites. The effects of cellulose chemical modification with three diisocyanates, i.e., hexamethylene diisocyanate (HDI), methylene diphenyl isocyanate (MDI), or toluene diisocyanate (TDI) on the surface properties of biocomposites were evaluated by water contact angle and surface roughness detected by atomic force microscopy (AFM). Biocomposites containing cellulose modified with HDI, MDI, or TDI revealed contact angle values of 93.5°, 97.7°, and 92.4°, respectively, compared to 88.5° for reference blend, indicating an enlarged hydrophobicity window. This action was further confirmed by increased fracture surface roughness and miscibility detected by microscopic observation (scanning electron microscopy (SEM) and AFM). An in-depth oscillatory rheological evaluation has identified MDI, followed by TDI, as the most efficient compatibilizer of the analyzed system. Correspondingly, thermogravimetric analysis and differential scanning calorimetry analyses showed more residue and higher melting temperatures for biocomposites, more promisingly with MDI and TDI modifiers. In conclusion, either incorporation or diisocyanate modification of cellulose affects both surface and bulk properties, providing vital insights into future developments in the field. Proper selection of diisocyanate modifier of cellulose may enable engineering of composites performance. [ABSTRACT FROM AUTHOR]

The industrial applications of the κ-carrageenases have been restricted by their poor thermostability. In this study, based on the folding free energy change (ΔΔG) and the flexibility analysis using molecular dynamics (MD) simulation for the alkaline κ-carrageenase KCgCD from Pseudoalteromonas porphyrae (WT), the mutant S190R was identified with improved thermostability. After incubation at 50 °C for 30 min, the residual activity of S190R was 63.7%, 25.7% higher than that of WT. The Tm values determined by differential scanning calorimetry were 66.2 °C and 64.4 °C for S190R and WT, respectively. The optimal temperature of S190R was 10 °C higher than that of WT. The κ-carrageenan hydrolysates produced by S190R showed higher xanthine oxidase inhibitory activity compared with the untreated κ-carrageenan. MD simulation analysis of S190R showed that the residues (V186–M194 and P196–G197) in F5 and the key residue R150 in F3 displayed the decreased flexibility, and residues of T169–N173 near the catalytic center displayed the increased flexibility. These changed flexibilities might be the reasons for the improved thermostability of mutant S190R. This study provides a useful rational design strategy of combination of ΔΔG calculation and MD simulation to improve the κ-carrageenase's thermostability for its better industrial applications. Key points: Mutant κ-carrageenase S190R is identified by rational design based on ΔΔG and MD simulation. Mutant κ-carrageenase S190R increases the thermostability. Mutant enzyme-treated κ-carrageenan exhibits high xanthine oxidase inhibitory activity. [ABSTRACT FROM AUTHOR]

To address the issue of low mechanical strength in self-supported hollow fiber membranes, a research study was conducted to fabricate polysulfone braid-reinforced hollow fiber (PSF BRHF) membranes for natural gas purification. In this study, polyethylene (PET) was used as a braid support. PSF BRHF membranes were fabricated by employing dip coating and drying technique. The BRHF membranes underwent comprehensive analysis, including the manipulation of polymer (PSF) concentration (15 wt%, 18 wt%, and 21 wt%) and the number of coating layers (1–4). Characterization of the fabricated membrane samples involved scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), gas separation performance testing, and mechanical strength testing. The results indicated that membranes fabricated with higher polymer concentrations exhibited a denser structure with a thicker separation layer. An increase in the separation layer thickness was also observed with an increasing number of coating layers. Importantly, all fabricated membrane samples demonstrated remarkable thermal stability. To assess the performance, gas separation tests were conducted using pure gases at 3 bar. Notably, the membrane sample with 21 wt% PSF and the 3rd coating layer (21_3 PSF) exhibited the most promising gas separation performance among all the samples selected to carry out the separation performance test, achieving a CO2/CH4 selectivity of 1.83. Mechanical strength testing revealed that 21_3 PSF BRHF (68.2 MPa) fabricated in this study outperformed conventional self-supported PSF hollow fiber membranes (9.44 MPa), as reported in the literature. These findings underscore the potential of BRHF membranes for natural gas purification, although further improvements are still possible. [ABSTRACT FROM AUTHOR]

Background: A ductile material, such as a polymeric material, releases energy during deformation. The dissipated energy can be evaluated as entropy generation. If the thermodynamic entropy generation can be measured, the stress state can be evaluated by the thermodynamic entropy generation. Objective: In this study, the thermodynamic entropy generation of Polyamide 6 (PA6) was obtained using differential scanning calorimetry (DSC) for a material subjected to arbitrary strain. Methods: Thermodynamic entropies were measured at the beginning and at each strain state of tensile tests by using DSC, and the volumetric strain was measured with Digital Image Correlation Method. Results: At the 25% strain just before the necking behavior, the volumetric strain of PA6 was ~4.8%, and the entropy was ~56 kJ/K∙m3. Furthermore, the thermodynamic entropy generation of PA6 in carbon fiber reinforced plastics was evaluated under tensile conditions. The results showed that the thermodynamic entropy generation just before the transverse cracking (as same as necking in matrix resin) was ~69 kJ/K∙m3 and the volumetric strain of PA6 in composite was ~ 3.56 %. As the results, the entropy generation and volumetric strain of PA6 showed almost same values in pure PA6 and PA6 in composite. Conclusions: Consequently, thermodynamic entropy generation can be measured the volumetric strain of matrix resin. [ABSTRACT FROM AUTHOR]

Differential scanning calorimetry (DSC) revealed an anti-sigmoidal composition dependence of the glass transition temperature in a binary mixture of dicyclohexylmethanol [ (C 6 H 11) 2 CHOH , DCHM] and tricyclohexylmethanol [ (C 6 H 11) 3 COH , TCHM]. The equimolar mixture, of which state was suggested to be robust by the dependence, was subjected to adiabatic calorimetry. The glass transition occurred around 257 K with a significant enthalpy relaxation. The excess heat capacity beyond the weighted average of heat capacities of neat compounds changes its sign from positive to negative upon the glass transition on cooling. The negative excess implies a denser molecular packing than neat glasses. The excess enthalpy is graphically given relative to T = 298.15 K. [ABSTRACT FROM AUTHOR]

Phenylboronic acids (PBAs) form stable complexes with fluoride. The effect of type (methoxy-, formyl-, and acetyl-) and position (ortho-, meta-, and para-) of electron-donating substitutions on the hydrolytic stability and acidity of PBAs, as well as their spectroscopic and physicochemical properties and their usage in spectrofluorimetric fluoride determination, were investigated. Thermal stabilities, relative predisposition, and resistance to dehydroboronation of related PBA isomers were investigated in detail and compared with the use of thermogravimetric analysis and differential scanning calorimetry profiles. Dehydroboronation reaction leads to the synthesis of related new cyclic anhydric forms — specifically named boroxines — which are clearly distinguished by Fourier transform infrared spectroscopy. PBAs were used for the complexation of fluoride for spectrofluorimetric fluoride determination in dental formulations [toothpastes (TPs) and mouth rinses (MRs)] and beverages [mineral waters (MiWs)]. Determination was done by fluorescence quenching of PBAs in response to increasing fluoride concentration. The regression equation was y = –15.336x + 983.17 (R2 = 0.9931), and was linear in the 1.4–3.0-mM range. Determinations were performed with relative errors (%) in a range of –5.60 to +1.23, –2.01 to +5.69, and –4.16 to +2.54 for MRs, TPs, and MiWs, respectively, relative to fluoride levels of commercial samples. Chemometric analyses (cluster analysis, CA, principal component analysis, PCA) were performed on the same real samples. Raw fluorescence data was investigated by PCA to check their significance in chemometric discrimination. Dendograms and score plots successfully discriminated samples in related groups. This is the first demonstration of spectrofluorometric fluoride determination based on the quenching of related isomers of PBAs thus far, also the potential of raw fluorescence data of these PBAs for chemometric discrimination studies on related pharmaceutical samples was highlighted for the first time. [ABSTRACT FROM AUTHOR]

Background: The goal of current research work is to develop and optimize curcumin-encapsulated nanostructured lipid carriers and to enhance therapeutic effect of curcumin after oral administration. Method: Curcumin-loaded nanostructured lipid carriers were developed by a single-step one-pot microwave-assisted technique. The preparation of curcumin-loaded nanostructured lipid carriers was optimized by employing two factors and three levels central composite design (Design Expert® software) taking concentration of lipid blend and surfactant as independent variables and particle size, polydispersity index, and zeta potential as dependent variables, to investigate the effect of formulation ingredients on the physicochemical characteristics of nanostructured lipid carriers. The optimized batch was investigated by Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, high-resolution transmission electron microscopy, in vitro drug release, stability studies, cytotoxicity, and in vivo anthelmintic studies. Results: The average particle size, polydispersity index, and zeta potential of the optimized batch were found to be 144 nm, 0.301, and − 33.2 mV, respectively, with an entrapment efficiency of 92.48%. The results of high-resolution transmission electron microscopy confirmed spherical shape of particles. In vivo antiparasitic studies included determining the duration of paralysis and eventual death of earthworms in the presence of test samples. The results of in vivo studies showed good anthelmintic potential for curcumin-loaded nanostructured lipid carriers as compared to albendazole in different concentrations. Cytotoxicity studies also confirmed the formulation to be nontoxic to Vero cells. In vitro drug release study showed 90.76 ± 0.01% release of curcumin in 24 h by following the Korsmeyer-Peppas model of release kinetics. Conclusion: The aforementioned results imply that microwave-developed nanostructured lipid carriers could be promising drug carriers and will aid in their fabrication for oral administration as a possible alternative for the treatment of other parasitic infections. Highlights: Curcumin-loaded nanostructured lipid carriers (Cr-NLCs) were prepared by a fast and easy single-step one-pot microwave-assisted technique. Implementation of 2 factors at 3 levels with central composite design (Design Expert® software) to investigate the influence of the formulation ingredients on the physicochemical properties of the NLCs. Optimized batch of Cr-NLC demonstrated nanosized particles with improved drug release characteristics, excellent entrapment efficiency and augmented physical stability. The anthelmintic potential of Cr-NLC was determined by a study on earthworms and was compared with albendazole. A cytotoxicity study was performed on Vero cells and evaluated in terms of IC50 value. [ABSTRACT FROM AUTHOR]

The continuous development of new wound dressing materials is necessary in order to achieve the best skin tissue regeneration properties. In this research, renewable foams, based on thermoplastic polyurethane (TPU) blended with polylactic acid (PLA), with and without 5 wt.% zinc oxide (ZnO) nanofiller were fabricated, and their biocompatibility with fibroblast cells was evaluated. The composites were prepared by thermally induced phase separation method (TIPS) for wound dressing application. These porous materials were structurally and thermally characterized using scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform spectroscopy (FTIR). The materials were also tested for their water uptake ability, hydrophilic/hydrophobic properties and water vapor transmission rate (WVTR). The fibroblasts presented a good interaction with these foams by adhering to the materials surface, pointing out that a higher content of TPU is favorable for cell viability. Moreover, no toxic effects of these novel materials were detected. The antibacterial tests showed proper antibacterial properties against Staphylococcus aureus and Pseudomonas aeruginosa. Thus, blending TPU foams with PLA could be validated as biocompatible platforms, suitable for wound dressing application. [ABSTRACT FROM AUTHOR]

The efficiency of carbon sequestration in abandoned soils depends on the stability of accumulated organic matter. The resistance of soil organic matter (SOM) of postagrogenic dark gray forest soils (Luvic Phaeozems (Aric, Cutanic, Densic)) in the subtaiga deciduous forest to microbial decomposition was estimated by soil respiratory activity. The thermal stability of SOM was determined by thermogravimetry and differential scanning calorimetry methods. Based on the increase of SOM thermal stability according to the rising temperature, four pools were separated in the SOM: thermally labile (thermal oxidation occurs at temperatures from 200 to 380°С), stable (380–460°С), overstable (460–520°С), and persistent (520–600°С). The thermally labile pool predominated in the SOM (58% on average) in the soil layer 0–30 cm. As soil depth increased, total portion of thermally stable pools (380–600°C) in the SOM increased and accounted for 63% on average at the depth of 70–100 cm. The temperature, at which thermal oxidation of half of the organic matter is reached (T50), was the indicator of SOM thermal stability. In the soil layer 0–30 cm T50 equaled to 362 ± 4°С, and in the soil layer 30–100 cm to 408 ± 4°С, and this reflected the increase with depth of the portion of thermally stable pools in the SOM. It was found that respiratory activity of abandoned soils decreased, as thermal stability, estimated by the ratio of the resistant pool to the labile pool, increased in SOM. [ABSTRACT FROM AUTHOR]

In this work an attempt is made to study the impact of the quenching rate upon structure, hyperfine interactions, magnetic and mechanical properties of Fe78Si9B13 metallic glasses. Other involved parameters in melt spinning method were kept invariant. Analytical techniques comprising X-ray diffraction, transmission Mössbauer spectrometry, vibration sample magnetometer, Vickers microhardness and differential scanning calorimetry were employed. Minor effect of quenching rate upon the macroscopic magnetic properties was detected. It was shown that notable changes in the local atomic arrangement, structure, and mechanical properties were unveiled, dominantly by represent the crystallization at the lowest quenching rate. [ABSTRACT FROM AUTHOR]

The dielectric constant (ε'), loss factor (tanδ), and ac conductivity (σac) of 30 Li2O–10CdO–(60 – x)-B2O3:xLn2O3, where (x = 0 and 1) and (Ln = Pr, Nd, Sm, and Eu) were investigated using a frequency range of 102–105 Hz and temperature ranging from 30 to 250°C in this work. The differential scanning calorimetry (DSC) technique was employed to confirm the glassy nature of the materials under study. The dielectric parameters ε', tan δ, and σac rise when rare-earth ions are added to the glass matrix at any frequency or temperature. Dielectric breakdown and activation energies are lower in doped than in undoped glasses while ac current flows through them at room temperature. Rare-earth ion doping's dielectric parameter values decrease with temperature as atomic number (Z) rises. The dielectric parameter values for the Pr3+ doped glass matrix is the highest. QM tunnelling model was used to describe the ac conduction behaviour of these glasses. [ABSTRACT FROM AUTHOR]

A technique for the experimental determination of the thermophysical characteristics of inactive aluminophosphate and borosilicate glasses by differential scanning calorimetry (DSC) is proposed and tested. The advantages of this measurement technique are shown. For glassy matrices of various compositions, the specific heat capacity and thermal conductivity coefficient are determined. The obtained experimental values make it possible to calculate the thermal conductivity values. The applicability of this method is proved by working with real samples of vitrified high-level waste to study their properties and form a database based on them. [ABSTRACT FROM AUTHOR]

This paper presents combined metal oxide catalysts for the decomposition of ammonium perchlorate, combining two transition metal oxides (iron and cobalt) deposited on the surface of a carbon support. Combined catalysts are obtained by impregnation and chemical precipitation methods. Catalyst samples containing various phases of iron and cobalt oxides are obtained by varying the calcination temperature. The structural and morphological features of the synthesized catalysts are studied using different methods: X-ray diffraction, scanning electron microscopy, and Brunauer–Emmett–Teller surface area. As shown by the study performed using differential scanning calorimetry, the synthesized combination catalysts manifest high catalytic activity during the thermal decomposition of ammonium perchlorate, reducing the peak temperature of the high-temperature stage of decomposition by more than 60°C. [ABSTRACT FROM AUTHOR]

An attempt to understand the relation between the burning characteristics and thermal decomposition in a wide range of pressure is made in the present investigation based on solid propellants with ammonium perchlorate as an oxidizer and 3,3-diazomethylepoxybutane and tetrahydrofuran as a fuel binder. The burning rate measurement is carried out in a wide range of pressure: 1.0, 3.0, 7.0, 13.8, 15.0, and 20.0 MPa. The inflection point of the pressure exponent for ammonium perchlorate with and without oxalate and the flame extinguishing point both appear at 13.8 MPa. Various mechanisms of burning rate reduction by the quaternary ammonium salt and oxalate are analyzed by theoretical analysis, thermogravimetric analysis, and differential scanning calorimetry analysis. The burning rate and decomposition of the oxidizer and fuel binder with combustion modifiers and their overall impact on propellant combustion are studied. Due to modifiers, a transition between kinetically controlled combustion and diffusion controlled combustion is found to occur. [ABSTRACT FROM AUTHOR]

In this study, we analyze the influences of carbon nanotube (CNT) addition on the martensite transformation and internal friction of Cu–Al–Ni shape-memory alloys (SMAs). X-ray diffraction and differential scanning calorimetry results demonstrate that Cu–13.5Al–4Ni–xCNT (x = 0, 0.2, 0.4, 0.6, and 0.8 wt%) SMA/CNT composites exhibit a β 1 (DO 3) ⇄ β 1 ′ (18 R) martensitic transformation. The martensitic transformation temperatures and transformation enthalpies of the martensitic transformation peaks for the Cu–13.5Al–4Ni–xCNT (x = 0–0.8 wt%) composites gradually decrease with the increase in the amount of CNT addition. Compared to the Cu–13.5Al–4Ni SMA, the Cu–13.5Al–4Ni–xCNT (x = 0.2–0.8 wt%) SMA/CNT composites exhibit significant improvements in the amount of dissipation of energy (storage modulus ( E ′)) and mechanical strength. However, the tan δ of the internal friction peak gradually decreases with the increase in the CNT content above 0.6 wt%. The reduction in tan δ is attributed to the decrease in the magnitude of the austenite-to-martensite transformation and precipitation of γ2 (Cu9Al4) phase particles, which impede the interface motion in between the parent/martensitic phase and martensitic phase. [ABSTRACT FROM AUTHOR]

To evaluate the possible thermal risks associated with the storage of octogen (HMX), non-isothermal differential scanning calorimetry (DSC) experiments were conducted in order to ascertain the kinetic model and parameters governing its thermal decomposition. DSC measurements indicate that HMX underwent a crystal transformation prior to thermal decomposition. A kinetic model for the autocatalytic thermal decomposition process was developed through the analysis of its primary exothermic peaks. Subsequently, numerical simulations were performed using the aforementioned kinetic model to assess the potential thermal explosion hazard of HMX under two distinct storage conditions. The comparison was made between the models of HMX autocatalytic decomposition temperature and thermal explosion critical temperature under two distinct storage conditions. The prediction of the influence of ambient temperature on the critical temperature of thermal explosion is conducted simultaneously. Finally, the thermal hazard parameters of HMX under different package quality are given. [ABSTRACT FROM AUTHOR]

The present study aimed to fabricate a novel polymeric spongy composite to enhance skin regeneration composed of Nystatin (antifungal agent) and Silver Nanoparticles (AgNps). Different formulations (F1–F8) were developed & characterized by using various analytical techniques. AgNps synthesized by chemical reduction method showed spherical morphology 2 µm in size showed by SEM and XRD. A fine porous structure of gel embedded with AgNps having an amorphous structure with 10 % crystallinity due to AgNps was found. IR spectra revealed no chemical interaction between polymers and Nystatin. An increase in thermal stability of formulation was observed till 700 ℃ analyzed by Differential Scanning Calorimetry. Cytotoxic analysis on L929 mouse skin fibroblast cells showed a decrease in cell viability as Ag concentration increased (inactivating Fibroblast and keratinocytes) while 10 mg composition was found safest concentration (94%). Optimized formulation (F2) presented in-vitro drug release up to 90.59% ± 0.76 at pH 7.4, swelling studies (87.5% ± 0.57), water retention (26.60 ± 0.34), pH (5.31 ± 0.03). In the animal burn model, the group that received CHG/Ag/Nystatin healed the wound significantly (p < 0.05). These results suggested that optimized carrier can be used for other anti-fungal drugs facilitating the early healing of the wound. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) can be used in odontology and orthopedic grafts to restore damaged bone due to its stable chemical characteristics, composition, and crystal structural affinity for human bone. A three-step hydrothermal method was used for the extraction of biogenic calcined HA from the buffalo waste bones at 700 °C (HA-700) and 1000 °C (HA-1000). Extracts were analyzed by thermogravimetric analysis, differential scanning calorimetry, X-ray fluorescence, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and in vivo examination of HA xenografts for femoral lesions in experimental rats. Crystallinity, purity, and morphology patterns showed that the HA main phase purity was 84.68% for HA-700 and 88.99% for HA-1000. Spherical HA nanoparticles were present for calcined HA-700 samples in the range 57–423 nm. Rats with critical bone lesions of 3 mm in diameter in the left femur treated with calcined HA-700 nanoparticles healed significantly (p < 0.001) faster than rats treated with HA-1000 or negative controls. These findings showed that spherical biogenic HA-700 NPs with a bud-like structure have the potential to stimulate both osteoconduction and bone remodeling, leading to greater bone formation potential in vivo. Thus, the calcined biogenic HA generated from buffalo waste bones may be a practical tool for biomedical applications. [ABSTRACT FROM AUTHOR]

Cranberry pomace considered as a by-product of fruit industry contains seeds which may be processed to highly nutritive oil. Conventional extraction methods may be, however, harmful to natural environment, thus alternative, ultrasound-assisted extraction method may be useful tool to reduce environmental impact. In the following study, sonication was applied to extract oil from cranberry seeds. The aim of the study was to determine the most efficient conditions of ultrasound-assisted extraction of oil and to investigate sonication influence on the properties of final product. Ultrasound amplitude and extraction time were independent variables; yield and maximum induction time of oils were responses. The most efficient conditions were amplitude of 95% and extraction time of 11.38 min. Model predicted extraction yield of 22.55 ± 0.36% (vs. actual 21.98 ± 0.08%) and induction time of 52.60 ± 0.95 min (vs. actual 61.95 ± 3.06 min). Detailed analyses of oil extracted in the most efficient conditions and the control sample were performed. Kinetic parameters of oil oxidation, fatty acid profile and distribution, melting characteristics studies were carried out. Sonication influenced activation energy of oxidation reaction, contribution of chosen fatty acids (oleic, α-linolenic and eicosenoic fatty acids) and distribution of oleic and α-linolenic fatty acids in sn-2 position of triacylglycerols. Slight changes in melting profile of oils were also recorded. Scanning electron microscopy of cranberry seeds revealed that ultrasound treatment resulted in pore enlargement and fat agglomeration damage. Additional studies of thermal properties of cranberry seeds: differential scanning calorimetry and modulated differential scanning calorimetry were performed, which confirmed that cranberry seeds may be a new source of oil with unique properties. [ABSTRACT FROM AUTHOR]

Thermodynamic properties of polycrystalline powders of ruthenium dichalcogenides have been studied using calorimetric isobaric heat capacity measurements in a wide temperature range. The adiabatic and differential scanning calorimetry data for ruthenium disulfide and ruthenium diselenide have been used to determine standard thermodynamic functions (heat capacity, entropy, enthalpy increment, and reduced Gibbs energy) of these compounds in the range 10–965 K. At 298.15 K, the functions of RuS2 are as follows: = 60.82 ± 0.12 J/(K mol), S° = 56.05 ± 0.11 J/(K mol), Н°(298.15 K) − Н°(0) = 9.75 ± 0.02 kJ/mol, and Ф° = 23.34 ± 0.05 J/(K mol). For RuSe2, we have obtained = 69.96 ± 0.14 J/(K mol), S° = 80.62 ± 0.16 J/(K mol), Н°(298.15 K) − Н°(0) = 13.05 ± 0.03 kJ/mol, and Ф° = 36.85 ± 0.08 J/(K mol). The data obtained above 298 K have been used to determine empirical coefficients of the Maier–Kelley and Khodakovsky equations. The absolute entropies obtained in this study for the ruthenium dichalcogenides, in combination with literature data, have made it possible to evaluate the Gibbs energy of formation of RuS2(cr) and RuSe2(cr) at 298.15 K. [ABSTRACT FROM AUTHOR]

Plasma polymerized (PP) methyl acrylate (MA) and vinyl acetate (VA) composite thin films were deposited onto glass substrate varying MA and VA monomer concentrations. Thickness of the composite polymers is observed to vary on the MA and VA monomer ratios, where MA is found more reactive. The FESEM images of the composite polymers show better surface morphology compared to those of the homopolymers. Appearance of broad absorption bands in the FTIR spectra of polymer indicates the structural changes compared to monomer during polymerization. Thermogravimetric analysis and differential scanning calorimetry indicate that composite films are thermally more stable (up to 617 K) compared to homopolymer thin films (563 K). The current density versus voltage (J–V) characteristics of PP(MA-VA) composite films (sandwiched between aluminum electrodes) with different MA and VA ratios showed that the J values of the composite films gradually increase with elevating VA monomer and also with temperature (298–373 K). On the other hand, this value increases with decreasing the thickness of the composite films, which complies with the other studies. The conduction of the thickness-dependent composite films showed Ohmic in nature in the lower voltage region (< 10 V) while the space charge-limited conduction is found to be dominated in the higher voltage region (> 10 V) operating over the entire range of temperature. The activation energy at room temperature was found to be ~ 0.019 eV in the Ohmic region and 0.260 eV in the non-Ohmic region. [ABSTRACT FROM AUTHOR]

The focus of this study revolves around the synthesis of AZ31 metal matrix composites (MMCs) reinforced with carbon nanotubes (CNTs) using the powder metallurgy technique. Various compositions of CNTs were incorporated into the AZ31 alloy matrix. The sintered specimens were analysed using microstructural characterization and Fourier transform infrared (FTIR) spectroscopy. Furthermore, differential scanning calorimetry (DSC) were conducted to investigate the impact of sintering on the processed composites. Corrosion studies were performed in a sodium chloride (NaCl) medium, and Tafel curves were plotted to assess corrosion behaviour. It was observed that composites enriched with 0.5 wt.% CNTs demonstrated the highest level of corrosion resistance among the synthesized AZ31 metal specimens. [ABSTRACT FROM AUTHOR]

The focus of this study revolves around the synthesis of AZ31 metal matrix composites (MMCs) reinforced with carbon nanotubes (CNTs) using the powder metallurgy technique. Various compositions of CNTs were incorporated into the AZ31 alloy matrix. The sintered specimens were analysed using microstructural characterization and Fourier transform infrared (FTIR) spectroscopy. Furthermore, differential scanning calorimetry (DSC) were conducted to investigate the impact of sintering on the processed composites. Corrosion studies were performed in a sodium chloride (NaCl) medium, and Tafel curves were plotted to assess corrosion behaviour. It was observed that composites enriched with 0.5 wt.% CNTs demonstrated the highest level of corrosion resistance among the synthesized AZ31 metal specimens. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) can be used in odontology and orthopedic grafts to restore damaged bone due to its stable chemical characteristics, composition, and crystal structural affinity for human bone. A three-step hydrothermal method was used for the extraction of biogenic calcined HA from the buffalo waste bones at 700 °C (HA-700) and 1000 °C (HA-1000). Extracts were analyzed by thermogravimetric analysis, differential scanning calorimetry, X-ray fluorescence, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and in vivo examination of HA xenografts for femoral lesions in experimental rats. Crystallinity, purity, and morphology patterns showed that the HA main phase purity was 84.68% for HA-700 and 88.99% for HA-1000. Spherical HA nanoparticles were present for calcined HA-700 samples in the range 57–423 nm. Rats with critical bone lesions of 3 mm in diameter in the left femur treated with calcined HA-700 nanoparticles healed significantly (p < 0.001) faster than rats treated with HA-1000 or negative controls. These findings showed that spherical biogenic HA-700 NPs with a bud-like structure have the potential to stimulate both osteoconduction and bone remodeling, leading to greater bone formation potential in vivo. Thus, the calcined biogenic HA generated from buffalo waste bones may be a practical tool for biomedical applications. [ABSTRACT FROM AUTHOR]

Solid–liquid equilibria (SLE) of binary mixtures of several n-alkanes (n-octadecane, n-eicosane, n-tetracosane, n-pentacosane, n-triacontane) and dibenzofuran covering the whole composition range were measured by differential scanning calorimetry (DSC) in a temperature range of 301–356 K. The dibenzofuran and the n-alkanes are completely miscible in the liquid state but non-miscible in the solid state, and in the context of this work, they seem to exhibit eutectic behavior. A linear trend is obtained for the eutectic temperature and eutectic composition versus the number of carbon atoms of n-alkane. The experimental data were compared to predictions made by using the ideal solution model, the DISQUAC model and several versions of the UNIFAC model, including the classical UNIFAC, the modified versions of Lyngby and Dortmund, and the recently proposed modified UNIFAC (NIST) model, to account for non-ideality in the liquid phase. Moreover, the experimental data were also compared with COSMO-RS predictions that utilize quantum chemical calculations and statistical thermodynamics to interpret the behavior of molecular interactions in the binary mixture. A good agreement was obtained between the predicted and the experimental temperatures. [ABSTRACT FROM AUTHOR]

Nanosized precursor powders of (1 – x)ZrSiO4‒xZrO(OH)2 are synthesized by the sol-gel method with the separate precipitation of components to obtain (1 – x)ZrSiO4‒xZrO2 ceramic composites. The thermal behavior of precursor powders is studied by differential scanning calorimetry and thermogravimetry (DSC/TG). Ceramic composites with a high level of microhardness are obtained by sintering powders, preliminarily calcined at 850°C, in air in the temperature range 1000‒1300°C. In the future, such ceramic composites can be used as matrices for solidification and isolating high-level waste (HLW). [ABSTRACT FROM AUTHOR]

Agro-industrial wastes are sustainable resources that have advantages as a reinforcement for polymeric matrices. This study examined the use of banana rachis fiber (BRF) in reinforcing the recycled high-density polyethylene (rHDPE) matrix. For this purpose, polymer composites with 5–20 wt% of BRF were prepared by the extrusion process using a twin-screw extruder and followed a hot press method. The structure of rHDPE/BRF composites and their characteristic peaks of degradation were successfully identified by the Fourier-transformed infrared spectroscopy and thermogravimetric analysis techniques, respectively, revealing a good dispersion of BRF in rHDPE. Differential scanning calorimetry results of the composites demonstrated that melt enthalpy decreases as the amount of BRF increases. XRD diffractograms revealed a crystallinity reduction of rHDPE due to the increase of fiber within the polymer matrix, which is reflected in the characteristic peaks' intensity decrease of HDPE. Variation in thermal and chemical properties with the addition of BRF in rHDPE was successfully evaluated in this study. Life cycle assessment for 1 kg composite production has also been evaluated. The banana rachis-rHDPE composite materials reduce the overall environmental impacts when the filler concentration increases. [ABSTRACT FROM AUTHOR]

Organomineral sorbents have been prepared by "mild" mechanical activation of air-dry clinoptilolite rocks with synthetic polymer (polyacrylamide) additions in an IVCh-3 laboratory-scale vibratory attritor (shear impact treatment for 3 min; specific mechanical energy delivered to the material, 2.16 kJ/g). The materials were characterized by scanning electron microscopy, infrared spectroscopy, differential scanning calorimetry, thermogravimetry, X-ray powder diffraction, and low-temperature nitrogen adsorption–desorption measurements. We have determined their specific surface area, specific pore volume, pore diameter, loose bulk and true densities, hygroscopic humidity, and oil sorption capacity. Modification of clinoptilolite rocks with 5 and 10 wt % polyacrylamide has been found to reduce the oil sorption capacity of the zeolites by 6–18%. The oil sorption capacity of the material modified with 20 wt % polyacrylamide was essentially the same as that of mechanically activated polymer-free clinoptilolite rocks. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis of crystalline ruthenium ditelluride (RuTe2) and its thermodynamic properties in the range from 10 to 965 K, evaluated from its isobaric heat capacity Cp determined using calorimetry. At low temperatures, between 6.86 and 335.11 K, the heat capacity of the synthesized material—pure, free of impurities and foreign phases—was determined by adiabatic calorimetry. In the range 315.3–965.3 K, Cp was determined by differential scanning calorimetry. The data obtained above 298 K have been used to determine empirical coefficients of the Maier–Kelley and Khodakovsky equations. In the range 10–965 K, we have evaluated the standard thermodynamic functions: heat capacity, entropy, enthalpy increment, and reduced Gibbs energy. At 298.15 K, we have obtained = 72.43 ± 0.14 J/(K mol), S° = 94.94 ± 0.19 J/(K mol), Н°(298.15 K) − Н°(0) = 14.60 ± 0.03 kJ/mol, and Ф° = 45.97 ± 0.09 J/(K mol). Using the absolute entropy determined by us and data in the literature and handbooks, we have estimated the standard Gibbs energy of formation of RuTe2: ΔfG°(RuTe2, cr, 298.15) = −130.5 ± 2.9 kJ/mol. [ABSTRACT FROM AUTHOR]

Dihydroquercetin (DHQ) is a natural occurring dihydroflavonol that has strong antioxidant and antibacterial activities. However, its application is limited due to its poor solubility. This study aims to improve the aqueous solubility of DHQ by complexing DHQ with β-cyclodextrin (β-CD) to boost its biological activity. DHQ was encapsulated with β-CD by freeze drying at a 1:1-M ratio. The structure of DHQ/β-CD complex prepared was elucidated by using Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, and 1H nuclear magnetic resonance (1H NMR). In addition, molecular docking further revealed two energetically favorable conformations of the DHQ/β-CD complex, in which DHQ interacted with β-CD via hydrogen bonds. Experimental results showed that the solubility of the DHQ increased 22.63-fold by encapsulating with β-CD. Also the dissolution rate, antioxidant activity and antibacterial activity of the DHQ were significantly improved by encapsulating. The encapsulating with β-CD solves the problem of the poor aqueous solubility of DHQ, and broadens the path for a more optimal use of the health promoting effect of DHQ in pharmaceutical and food products. [ABSTRACT FROM AUTHOR]

The increasing demand for natural products and biotechnological activities from bees facilitate their widespread use in food preservation and beneficial effects on humans. This study aimed to prepare and characterize the nano-capsules of Qaluiobia (PQG) governorates propolis extracted with water, ethanol and supercritical fluid-carbon dioxide at 50 °C with co-solvent. Propolis bioavailability was analyzed and introduced to prepare crackers to extend their shelf life. Nano-encapsulation was examined using transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and antioxidant activity. Ethanol and supercritical fluid-carbon dioxide (SCF-CO2) at 50 °C with ethanol as co-solvent recorded higher yield, antioxidant activities, total phenolics and total flavonoids. SCF-CO2 extracts had a higher flavonoid concentration. It was revealed that propolis nano-capsules had high-temperature stability and cytotoxic effects against the three tested human cancer cell lines (i.e. PC3, MCF7 and HePG2). The higher overall acceptability of crackers fortified with PQG was achieved with SCF-CO2 at 50 °C and ethanol extract nano-capsules, i.e. 86.57% and 86.29% respectively. The higher ability to retain antioxidant activity reduces the increase of peroxide value (PV), preventing rancidity and increasing the shelf life of crackers during the storage period. Practical application: This study can provide a suitable method for extracting bioactive compounds from propolis, and improve the biological properties and activities by nano-encapsulation, also reveals the extent of its use as a natural antioxidant and anticancer and its application in bakery products as a functional food. [ABSTRACT FROM AUTHOR]

Nowadays zinc nanoparticles (NPs) have attracted many applications in display technology. Due to the dispersion of nanoparticles in liquid crystals (LCs), the display properties are enhanced. The present work focuses on the significant changes in the properties of LC displays with the dispersion of ZnO NPs. Schiff-based LC compounds like p–n-decyloxybenzaldehyde and corresponding p–n-alkoxy anilines (10O.Om, with m = 3, 6) are prepared with the dispersion of ZnO NPs (1 wt.%). The tools used to characterize the nanoparticles in LCs are X-ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and modified spectrometer. With XRD studies, the size of ZnO NPs is determined. By using SEM and EDS, the homogeneous dispersion and elemental analysis is estimated. With the data of POM, the textural analysis is examined. With DSC, the phase transition temperature of different phases is noted. With the modified spectrometer, the values of refractive indices and birefringence are determined. Furthermore, with these values, the molecular orientational order parameter S is measured by the Kuczynski and Haller extrapolation methods. It is observed that the birefringence and order parameter values are decreased with the dispersion of 1 wt.% ZnO NPs in Schiff-based LC compounds. [ABSTRACT FROM AUTHOR]

The present study aimed to fabricate a novel polymeric spongy composite to enhance skin regeneration composed of Nystatin (antifungal agent) and Silver Nanoparticles (AgNps). Different formulations (F1–F8) were developed & characterized by using various analytical techniques. AgNps synthesized by chemical reduction method showed spherical morphology 2 µm in size showed by SEM and XRD. A fine porous structure of gel embedded with AgNps having an amorphous structure with 10 % crystallinity due to AgNps was found. IR spectra revealed no chemical interaction between polymers and Nystatin. An increase in thermal stability of formulation was observed till 700 ℃ analyzed by Differential Scanning Calorimetry. Cytotoxic analysis on L929 mouse skin fibroblast cells showed a decrease in cell viability as Ag concentration increased (inactivating Fibroblast and keratinocytes) while 10 mg composition was found safest concentration (94%). Optimized formulation (F2) presented in-vitro drug release up to 90.59% ± 0.76 at pH 7.4, swelling studies (87.5% ± 0.57), water retention (26.60 ± 0.34), pH (5.31 ± 0.03). In the animal burn model, the group that received CHG/Ag/Nystatin healed the wound significantly (p < 0.05). These results suggested that optimized carrier can be used for other anti-fungal drugs facilitating the early healing of the wound. [ABSTRACT FROM AUTHOR]

Background: The objective of the present investigation was to obtain directly compressible agglomerates of ibuprofen with nicotinamide by a quasi-emulsification solvent diffusion technique. Ibuprofen-nicotinamide agglomerates were prepared by quasi-emulsification solvent diffusion technique using ethanol (good solvent), water (poor solvent), and chloroform (bridging liquid). The prepared agglomerates were characterized by ATR-FTIR, powder X-ray diffraction, differential scanning calorimetry, and scanning electron microscopy and were evaluated for tableting performance and in vitro drug release. To appropriately identify the hydrogen bonding sites, a thorough understanding of the structures of API and coformer is necessary, hence molecular docking approach was implemented to depict the interaction between the proposed coformer and COX-2 protein (PDB Id:4PH9). Results: The percent yield of agglomerates was in the range of 85–98 w/w%, and drug content for all batches was in the range of 96–99%. The microphotographs showed irregular circularly shaped agglomerates. ATR-FTIR study showed a strong possibility of hydrogen bonding between ibuprofen and nicotinamide. The crystallinity of ibuprofen was slightly reduced and confirmed by P-XRD and DSC. Crushing strength and friability studies showed good handling qualities of ibuprofen agglomerates. Heckel plot studies showed low mean yield pressure and high tensile strength, indicating excellent compressibility and compactibility of ibuprofen agglomerates. More than 90% drug release was obtained within 60 min in PBS (pH 7.4). The docking studies revealed that nicotinamide individually has –CDOCKER energy 16.8109 where coformer showed 29.0584, which indicates coformer has a better binding affinity to target as compared to nicotinamide individual. Conclusions: It can be concluded that the agglomerates improved the dissolution, tableting performance, and solid-state properties of ibuprofen and hence can be useful to improve the therapeutic performance of ibuprofen. [ABSTRACT FROM AUTHOR]

Hollow sphere polymeric pigments prepared from styrene-acrylate copolymer referred to as organic opacifiers (OP) are the primary substitutes of TiO2 in water-based architectural paints. This study describes the method for the quantification of OP in water-based paints using dynamic mechanical thermal analysis (DMTA). The significance of DMTA in visualizing the glass transitions over differential scanning calorimetry (DSC) is showcased. The glass transition temperature (Tg) of OP was found to be ~109°C by DSC method and ~125°C by DMTA method. The peak intensity of tan δ at Tg of OP in paints (tan δ2) is not affected by the curing time and linearly increases as a function of OP concentration in water-based paints, irrespective of the difference in volume solids. DMTA can efficiently quantify OP in paint film if it is ≥3.3% (w/w). Increasing concentration of a coalescing solvent in water-based paints has a detrimental effect on the peak intensity of tan δ2. Two commercially available grades of OP having difference in the core-shell morphology have been studied. Internal morphology of the OP studied by scanning electron microscopy has a significant effect on the peak intensity of tan δ2 thereby affecting its opacity performance in paints. Owing to the limited effect of curing time, volume solids and coalescing solvent on the peak intensity of tan δ2 of paints, this method can be used for the quantification of OP in paints, as it has been validated with seven commercially available paints with known OP contents. [ABSTRACT FROM AUTHOR]