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3,4-bis(3-nitrofurazan-4-yl) furoxan (DNTF) is one of the third-generation energetic compounds with excellent comprehensive properties, which can be added to polymer bonded explosive (PBX) to improve energy levels and regulate sensitivity, so the compatibility of DNTF with other components in PBX, especially the binder, is the first question. Herein, two typical hydrocarbon polymers commonly used in PBX, which are hydroxyl-terminated polybutadiene (HTPB) and polyisobutylene (PIB), were selected as the binder, and the compatibility of HTPB and PIB with DNTF was investigated by differential scanning calorimetry (DSC), the vacuum stability test (VST), and in situ infrared spectroscopy (in situ IR). The results of compatibility experiments were verified by using the binding energy and solubility parameter criteria in molecular dynamics (MD). Experimental and MD simulation results showed that DNTF could be compatible with PIB but incompatible with HTPB. The frontier molecular orbital theory in quantum chemistry (QC) was adopted to explore the frontier orbital electron distribution and energy levels of DNTF/HTPB and DNTF/PIB composite systems to better understand the microscopic compatibility mechanism. The compatibility results of the two composite systems were explained from the perspective of electron transfer. All these can deduce that a hydrocarbon polymer binder with a saturated carbon–hydrogen bond at the end of the molecular chain has good compatibility with DNTF, compared with a hydroxyl group, which has bad compatibility with DNTF. [ABSTRACT FROM AUTHOR]

The long-term storage performance of energetic multilayer nanofilms is of great significance for their applications. In this paper, it is proposed to add a 10 nm Cu barrier layer between Al/CuO composite films to increase their storage stability. The Al/CuO composite film and Al/Cu/CuO composite film were aged for 14 days in an environment with a relative humidity of 40% and a temperature of 71 °C. Scanning electron microscopy and differential scanning calorimetry were used to analyze the microstructure and thermodynamic properties of the energetic films before and after aging, and the electrical detonation performance and ignition ability of energy-containing semiconductor bridges were studied. The results indicate that after aging for 14 days in an environment with a relative humidity of 40% and a temperature of 71 °C, the Al layer of the Al/CuO composite film becomes thinner, the Al2O3 interface layer increases, and the heat release decreases. The interlayer microstructure of the Al/Cu/CuO energetic multilayer nanofilms did not change significantly, and the addition of a 10 nm Cu layer formed a low-temperature Al–Cu alloy, reducing the reaction initiation temperature from 626 to 570 °C. The critical ignition time and critical ignition energy of the Al/CuO-energetic semiconductor bridge (ESCB) increased, the flame duration shortened from 440 to 300 μs, the flame size decreased by 50%, the plasma temperature decreased, and aging had no significant effect on the electrical explosion performance of Al/Cu/CuO-ESCB. After aging for 14 days in an environment with a relative humidity of 40% and a temperature of 71 °C, the maximum ignition gap of B/KNO3 for Al/CuO-ESCB decreased from 1.4 to 1.2 mm, while the maximum ignition gap for Al/Cu/CuO-ESCB remained at 1.6 mm, which significantly improved the ignition performance and long storage performance of the energetic semiconductor bridge. [ABSTRACT FROM AUTHOR]

Dynamic heterogeneity is a fundamental characteristic of glasses and undercooled liquids. The heterogeneous nature causes some of the key features of systems' dynamics such as the temperature dependence of nonexponentiality and spatial enthalpy fluctuations. Commonly used phenomenological models such as Tool–Narayanaswamy–Moynihan (TNM) and Kovacs–Aklonis–Hutchinson–Ramos fail to fully capture this phenomenon. Here we propose a model that can predict the temperature-dependent nonexponential behavior observed in glass-forming liquids and glasses by fitting standard differential scanning calorimetry curves. This model extends the TNM framework of structural relaxation by introducing a distribution of equilibrium fictive temperature ( T f e ) that accounts for heterogeneity in the undercooled liquid. This distribution is then frozen at the glass transition to account for the heterogeneous nature of the glass dynamics. The nonexponentiality parameter βKWW is obtained as a function of temperature by fitting the Kohlrauch-Williams-Watts (KWW) equation to the calculated relaxation function for various organic and inorganic undercooled liquids and glasses. The calculated temperature dependent βKWW shows good agreement with the experimental ones. We successfully model the relaxation dynamics far from equilibrium for two silicate systems that the TNM model fails to describe, confirming that temperature dependent nonexponentiality is necessary to fully describe these dynamics. The model also simulates the fluctuation of fictive temperature δTf during isothermal annealing with good qualitative agreement with the evolution of enthalpy fluctuation reported in the literature. We find that the evolution of enthalpy fluctuation during isothermal annealing heavily depends on the cooling rate, a dependence that was not previously emphasized. [ABSTRACT FROM AUTHOR]

The reversible hydrogenation/dehydrogenation of aromatic molecules, known as liquid organic hydrogen carriers (LOHCs), is considered an attractive option for the safe storage and release of elemental hydrogen. The LOHC systems based on the alkoxy-naphthalene/alkoxy-decalin studied in this work can become potentially attractive from the point of view of the thermodynamic conditions of the reversible hydrogenation/dehydrogenation processes. This work reports the results of a complex experimental investigation of the thermochemical properties of the reactants of the LOHC systems. The enthalpies of formation were measured using high-precision combustion calorimetry, the enthalpies of vaporization and sublimation were derived from the vapor pressure–temperature dependencies measured using the transpiration method, and the melting temperatures and enthalpies of fusion were measured using the differential scanning calorimetry method. The liquid-phase enthalpies of formation of methoxy- and ethoxy-substituted naphthalenes and methoxy- and ethoxy-substituted decalins were derived and used for the thermodynamic analysis of hydrogenation/dehydrogenation reactions and transferhydrogenation reactions. [ABSTRACT FROM AUTHOR]

The glass transition (Tg) behavior and enthalpy recovery of polystyrene nanorods within an anodic aluminum oxide (AAO) template (supported nanorods) and after removal from AAO (unsupported nanorods) is studied using Flash differential scanning calorimetry. Tg is found to be depressed relative to the bulk by 20 ± 2 K for 20 nm-diameter unsupported polystyrene (PS) nanorods at the slowest cooling rate and by 9 ± 1 K for 55 nm-diameter rods. On the other hand, bulk-like behavior is observed in the case of unsupported 350 nm-diameter nanorods and for all supported rods in AAO. The size-dependent Tg behavior of the PS unsupported nanorods compares well with results for ultrathin films when scaled using the volume/surface ratio. Enthalpy recovery was also studied for the 20 and 350 nm unsupported nanorods with evolution toward equilibrium found to be linear with logarithmic time. The rate of enthalpy recovery for the 350 nm rods was similar to that for the bulk, whereas the rate of recovery was enhanced for the 20 nm rods for down-jump sizes larger than 17 K. A relaxation map summarizes the behavior of the nanorods relative to the bulk and relative to that for the 20 nm-thick ultrathin film. Interestingly, the fragility of the 20 nm-diameter nanorod and the 20 nm ultrathin film are identical within the error of measurements, and when plotted vs departure from Tg (i.e., T − Tg), the relaxation maps of the two samples are identical in spite of the fact that the Tg is depressed 8 K more in the nanorod sample. [ABSTRACT FROM AUTHOR]

The present work describes the preparation of a new series of chalcogenide glasses in an As14Sb26S(60−x) (AgI)x system intending to explore its thermal, structural, optical, mechanical, and electrical properties. The differential scanning calorimetry results of the studied glasses show the sharp decrease in glass transition temperature (Tg) with the successive incremental inclusion of AgI in the composition, implying the structural changes in the glass network. A thorough Raman analysis corroborates the occurrence of changes in the glass network due to the formation of AsI3 units and Ag–S–As bonds with increasing AgI content. Also, structural changes can be reflected with the change in the optical bandgap (Eg) that was calculated using Tauc equations where it was found that Eg is in harmony with the observed structural variations of glasses. The studied glasses possess a transmittance window (∼0.68–12 μm) with transmittance above 60% in the mid-infrared region. These structural changes are closely related to the significant enhancement of conductivity of the present glasses from 10−8 to 10−6 S/cm at 373 K with a decrease in activation energies. Impedance spectra for the glass with highest AgI revealed the presence of two different relaxation processes. AC conductivity data followed an Arrhenius behavior as well as Jonscher's power law. The present work provides insights into glass network modifications due to silver iodide inclusion and its role in the enhancement of conductivity. [ABSTRACT FROM AUTHOR]

The impact of successive replacement of K+ by Na+ on the megahertz–gigahertz polarization response of 0.25[fKSCN + (1 − f)NaSCN] + 0.75CH3CONH2 deep eutectic solvents (DESs) was explored via temperature-dependent (303 ≤ T/K ≤ 343) dielectric relaxation (DR) measurements and computer simulations. Both the DR measurements (0.2 ≤ ν/GHz ≤ 50) and the simulations revealed multi-Debye relaxations accompanied by a decrease in the solution static dielectric constant (ɛs) upon the replacement of K+ by Na+. Accurate measurements of the DR response of DESs below 100 MHz were limited by the well-known one-over-frequency divergence for conducting solutions. This problem was tackled in simulations by removing the zero frequency contributions arising from the ion current to the total simulated DR response. The temperature-dependent measurements revealed a much stronger viscosity decoupling of DR times for Na+-containing DES than for the corresponding K+ system. The differential scanning calorimetry measurements indicated a higher glass transition temperature for Na+-DES (∼220 K) than K+-DES (∼200 K), implying more fragility and cooperativity for the former (Na+-DES) than the latter. The computer simulations revealed a gradual decrease in the average number of H bonds (⟨nHB⟩) per acetamide molecule and increased frustrations in the average orientational order upon the replacement of K+ by Na+. Both the measured and simulated ɛs values were found to decrease linearly with ⟨nHB⟩. Decompositions of the simulated DR spectra revealed that the cation-dependent cross interaction (dipole-ion) term contributes negligibly to ɛs and appears in the terahertz regime. Finally, the simulated collective single-particle reorientational relaxations and the structural H-bond fluctuation dynamics revealed the microscopic origin of the cation identity dependence shown by the measured DR relaxation times. [ABSTRACT FROM AUTHOR]

The dynamics of polymer nanocomposites varies depending on the physics and chemistry at the polymer–nanoparticle interface. The physical aging of the nanocomposites is accelerated or retarded based on interfacial interactions and the state of polymer adsorption at the interfaces. In this study, we investigated the aging kinetics of silica–polystyrene nanocomposites using differential scanning calorimetry, focusing on the effect of local conformations of chains adsorbed on the nanofiller surface. The results show that the temperature dependence of the aging rate follows a Vogel–Fulcher–Tammann relationship at high temperatures, whereas it exhibits an Arrhenius-like behavior below a characteristic temperature (Tc). Notably, at T < Tc, the aging rate decreases with increasing loop height of the chains adsorbed on the filler surface, but the activation energy remains unchanged. We proposed that the suppression of the aging rate at T < Tc is likely related to an increase in the length scale over which the slow interfacial dynamics can propagate due to the increased topological interactions between the chain loops of a larger size and the free chains in the matrix. The increased packing frustration occurring at the filler surface occupied by the larger loops might also contribute to the decreased aging rate. [ABSTRACT FROM AUTHOR]

In this work, the magnetocaloric effect in Ni50Mn36In5Sb9 alloy was increased by more than 50% through directional solidification, and the magnetic entropy change increased to 36.2 J kg−1 K−1 under the field of 5 T. The calculated results of differential scanning calorimetry curves confirmed the enhanced entropy change, which also increased from 29.7 to 40.7 J kg−1 K−1. Moreover, first-principles calculations show that the surface formation energy along the L21 (220) plane is the lowest at room temperature, and it is easy to form and undergo martensitic transformation from the (220) crystal plane. Directional solidification causes the alloy to grow basically toward the (220) crystal plane, improve atomic ordering, reduce grain boundaries, and increase grain size. Thereby, the magnetic entropy change is enhanced. [ABSTRACT FROM AUTHOR]

In the current work, laser thermal treatment of the FeSiB amorphous foil with a single linear laser track was carried out. The resultant microstructure and phase evolution were examined with the aid of x-ray diffraction, differential scanning calorimetry, and site-specific transmission electron microscopy. The laser power was kept constant at 100 W, whereas, laser beam scanning speeds were varied in the range of 500–235 mm/s, generating corresponding laser fluences of 0.42–0.91 J/mm 2 on the sample surface. Laser fluences of up to 0.48 J/mm 2 structurally relaxed the FeSiB foil, retaining the amorphous structure. Laser fluences of higher than 0.48 J/mm 2 led to partial crystallization of FeSiB amorphous foils. The crystallite sizes were in the range of 11–31 nm (laser fluence of 0.49–0.91 J/mm 2). α -FeSi formed as a major phase of partial crystallization while its quantity steadily increased from 3.6 to 46 vol. % with laser fluence (laser fluence 0.49–0.91 J/mm 2). Fe 2 B formed in recognizable quantities (≥ 2%) for laser fluences ≥ 0.53 J/mm 2. Laser fluences leading to structural relaxation and evolution of predominantly α -FeSi phase exerted minimal effects on ratios of intrinsic coercivities to saturation compared to the as-cast FeSiB amorphous foil. On the contrary, formation of Fe 2 B in significant quantities (≥ 2 %) led to the steady increase in intrinsic coercivities and remanence to saturation ratios as a function of laser fluence indicating a loss in soft magnetic characteristics. Nonetheless, continuous increase in fractions of α -FeSi with laser fluence led to a steady improvement in saturation magnetostriction of the FeSiB foil. [ABSTRACT FROM AUTHOR]

1-propanol/water mixtures over the whole composition range (0 < XV ≤ 1; XV is the 1-propanol volume fraction) are shown to be structurally and dynamically heterogeneous. By combining structural (x-ray diffraction), thermodynamic (differential scanning calorimetry) and dynamical probes (dielectric spectroscopy) we construct the pertinent phase diagram. It consists of liquid 1-propanol, liquid water, hexagonal ice and different hydrates, the latter sharing the same lattice. The phase diagram can be discussed in terms of four regimes, all having in common a droplet arrangement of the minority component. When water droplets are strongly confined by 1-propanol (regime I, 0.92 < XV ≤ 1; "soft" confinement), water is unable to crystallize. It has dynamics reminiscent to the ultra-viscous water phase known as high-density liquid (HDL). When water droplets are moderately confined (regime II, 0.75 < XV ≤ 0.92) water can crystallize via homogeneous nucleation. Strikingly, the homogeneous nucleation temperature is at 205 K, well within "no-man's land." The result is in line with earlier reports that soft confinement is the key to enter into the "no-man's land". When 1-propanol is the minority component (regimes III and IV), the structure and the dynamics are dominated by the 1-propanol/water interface with the formation of hydrates. The corresponding dynamical features suggest a link between hydrate formation and the two metastable phases of ultra-viscous water, HDL and low-density liquid. [ABSTRACT FROM AUTHOR]

G-quadruplexes are four-stranded DNA structures that have been found in the cell and are thought to act as elements of control in genomic events. The measurements of the thermodynamic stability, ΔG, of G-quadruplexes shed light on the molecular forces involved in the stabilization of these structures. In thermodynamic studies, the differential heat capacity, ΔCP, of the folded and unfolded states of a G-quadruplex is a fundamental property that describes the temperature dependences of the differential enthalpy, ΔH, entropy, ΔS, and free energy, ΔG. Despite its recognized importance, the ΔCP of G-quadruplex unfolding has not been measured directly. Here, we use differential scanning calorimetry to evaluate changes in heat capacity, ΔCP, accompanying the unfolding transitions of G-quadruplexes formed by modified DNA sequences from the promoter regions of the c-MYC, VEGF, and Bcl-2 oncogenes. The average value of ΔCP is 0.49 ± 0.12 kcal mol−1 K−1. Our analysis revealed that disregarding ΔCP leads to significant errors in extrapolated values of the differential enthalpy, ΔH, and entropy, ΔS, of the folded and unfolded DNA conformations. Although the compensation between ΔH and ΔS weakens the effect of ΔCP on the differential free energy, ΔG, neglecting ΔCP may still result in relative errors in ΔG extrapolated to room temperature as great as 140%. We emphasize the importance of proper consideration of the effect of ΔCP in conformational studies of guanine-rich DNA molecules. [ABSTRACT FROM AUTHOR]

This study presents an investigation into mechanical and thermal properties, as well as the microstructure of Automated Fiber Placement-manufactured laminates using a novel carbon fiber-reinforced low-melt polyaryl ether ketone polymer material. The material's lower melting temperature and lower melt viscosity as compared to established high-temperature thermoplastic materials as PEEK, promises favourable characteristics for the Automated Fiber Placement process. This work aims at in-situ consolidation and the influence of a heated tooling and a post process tempering step, which both turned out to be promising in previous investigations. Laminates were manufactured using a cold tooling, a heated tooling configuration, a cold tooling with a subsequent tempering process step and a hot-pressed reference laminate. Differential Scanning Calorimetry showed that crystallinity values more than doubled for the heated tooling and post process tempering configurations, compared to the cold tooling, reaching 24% and 30%, respectively. Mechanical strength values showed an increase in interlaminar shear strength and compression strength but did not increase to the same extent as was expected from the increase in crystallinity. With Scanning Electron Microscopy differences in the microscopic structure of the polymer matrix could be detected. While the post process tempering step leads to a mostly lamellar crystalline structure, the heated tooling configuration and the post process hot pressing induce a predominance of crystalline spherulites, which might positively affect the mechanical performance. Computed Tomography scans revealed a high amount of porosity in the in-situ-manufactured samples and unprocessed tape material, which likely mitigated the positive effect of increased crystallinity. [ABSTRACT FROM AUTHOR]

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]

To enhance the performance of carbon fiber reinforced polymer (CFRP), it is crucial to establish robust interactions between epoxy and carbon fiber fabric (CFF). Herein, CFF was treated by an optimized H2O2/H2O/O3 oxidation method. The chemical and physical properties of the treated CFFs were meticulously characterized. For comparison, CFF, O3 treated CFF, and H2O/O3 treated CFFs were also examined. It was found that H2O2/H2O/O3 oxidized CFF more effectively than either O3 or H2O/O3. Reactive O groups were extensively grafted onto the surface of the H2O2/H2O/O3 oxidized CFF, leading to an increase in surface energy. Additionally, numerous defects were introduced on the surface of the H2O2/H2O/O3 oxidized CFF, significantly enhancing its surface roughness. Consequently, the interlaminar shear strength of H2O2/H2O/O3 oxidized CFF reinforced epoxy composite reached 63.31 ± 2.50 MPa, which is 43.3% higher than that of CFF reinforced epoxy composite. The fracture surface morphology and differential scanning calorimetry studies confirmed the presence of strong interfacial chemical interactions, while the increased surface roughness ensured robust interfacial physical interactions. Based on these findings, the mechanisms of the H2O2/H2O/O3 oxidized CFF reinforcing epoxy were proposed. The present work aims to give out some ideas for the fabrication of green and advanced CFRP. Highlights: CFF was effectively oxidized by an optimized H2O2/H2O/O3 method eco‐friendly.Improved the interlaminar shear strength of the epoxy composite by 43.3%.Both the strong interfacial chemical and physical interactions were confirmed.The reinforcing mechanism is attributed to the robust interactions. [ABSTRACT FROM AUTHOR]

Jelly glue made of gelatin is frequently used in the packaging industry. The purpose of this study is to determine whether starch and polyvinyl alcohol (PVA), which were introduced at a 1.0% concentration, could be used to develop with improvement in the performance properties of jelly adhesives that are being prepared. By examining viscosities at different temperatures, pH, water contact angles, differential scanning calorimetry (DSC), tensile strength on wood and setting speed observation on coated paper, and performing pencil hardness tests on films, the effect of adding starch and PVA as a binder on physical, thermal, and mechanical properties were studied. When starch and PVA were added to the jelly glue, DSC data showed a substantial rise in the glass transition temperature, which were further confirmed by film hardness testing. The addition of starch increased the adhesive's viscosities at different temperatures. When compared to an original sample, the tensile strength with starch increased by ~ 74% after 24 h of bonding in a dry environment. The jelly adhesive with starch showed increased in water resistance which was also validated from contact angle test. Unlike PVA-based jelly glue, the hydrogen bonding in starch and gelatin showed superior mechanical properties. This research discusses starch as a potential substitute for the development of jelly adhesive. The technique developed offers an easy and useful path to adhesives with increased water resistance and bonding strength by using starch as a binder. Ecologically sound, sustainable, and economically acceptable were the methods used to increase jelly adhesive's resistance to moisture. The study's overall finding highlights the superior and sustainable adhesive performance of jelly glue based on starch as a packaging adhesive. [ABSTRACT FROM AUTHOR]

This research aims to improve the flame-retardant properties of wood–plastic composites with different recycled plastics. Acrylonitrile butadiene styrene (ABS) and polyvinyl chloride (PVC), flame-retardant materials, and recycled polypropylene (PP) were used as matrix in this research. Recycled ethylene propylene diene monomer (EPDM) with flame-retardant properties was also added to mix with rubberwood flour (RWF) to improve mechanical properties. The rubberwood flour, coupling agent (MAPP), and lubricant are fixed at 44.5%, 4%, and 1%, respectively, whereas recycled plastics and EPDM rubber contents are in the range of 30.5–50.5% and 0–20%, respectively. The composite materials were manufactured into panels using a twin-screw extruder and hot press machine. The experimental results were statistically analyzed by analysis of variance (two-way ANOVA) at a 95% confidence level. The highest values of the mechanical parameters of wood–plastic composites reinforced with recycled polypropylene (RWF44.5PP50.5) were 15.89 MPa, 42.26 MPa, 41.79 MPa, and 0.0202 J for tensile strength, flexural strength, compression strength, and impact strength, respectively. An increasing EPDM rubber content of wood–plastic composites provided better thermal properties. The thermogravimetric analysis and differential scanning calorimetry of hybrid composites with recycled ABS (RWF44.5ABS30.5EPDM20) obtained the highest value with thermal stability in the range of 255–284 °C. For the flammability properties, the hybrid composites with high EPDM rubber content were less flammable. Recycled PVC with content of RWF44.5PVC50.5 outperformed hybrid composites reinforced made from ABS and PP in terms of UL-94 and the limiting oxygen index with values of 25.73%. [ABSTRACT FROM AUTHOR]

Oil shale is a critical strategic resource with enormous reserves. In-situ combustion technology offers great potential for the development of oil shale reserves. In this study, the combustion behavior and kinetics of Domanik oil shale were investigated using High Pressure Differential Scanning Calorimetry. Additionally, the thermal behavior of the oil shale during combustion was studied by using a self-designed Porous Medium Thermo-Effect Cell. Furthermore, the stability of the combustion front and the upgrading effect of the combustion process were investigated with Visual Combustion Tube, and the produced oil was analyzed to evaluate its quality. The results showed that the combustion process of oil shale is characterized by two reaction stages. The oil shale was found to form enough coke residue during the oxidation reactions to allow for stable propagation of a combustion front. The produced oil was of better quality compared to the naturally produced bitumen in oil shale, which indicates that the combustion process had a good upgrading effect. The findings of this study provide a better understanding of the in-situ upgrading process of kerogen and provide significant knowledge about the combustion mechanism of oil shale for its potential development using the in-situ combustion technology. [ABSTRACT FROM AUTHOR]

In the present study, polystyrene (PS) is chemically modified with diethyl(acryloyloxymethyl)phosphonate (DEAMP) and an N‐containing monomer, selected from different classes of compounds, via a ter‐polymerization route; thus, exploring possible P–N synergistic effects on fire retardance of the base polymer. The successful incorporation of P and N monomeric units is confirmed by Fourier Transform Infrared (FT‐IR), 1H and 31P Nuclear Magnetic Resonance (NMR) spectroscopies. The thermal degradation and combustion attributes of modified polymeric materials are measured using standard techniques, including Thermo‐Gravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), "bomb" calorimetry, and Pyrolysis Combustion Flow Calorimetry (PCFC). The thermal and combustion studies demonstrate that the thermal stability and combustion characteristics of styrenic polymers are significantly altered by the presence of even nominal amounts of P‐ and N‐containing groups, and in certain cases, synergistic interactions of these groups are also evident. For instance, as revealed by TGA, the extent of char formation, under the oxidative atmosphere, in the prepared ter‐polymers, is enhanced by 16–44%, when compared to the unmodified PS. The heat release rates and heat release capacities of ter‐polymers, measured using the PCFC technique, are reduced by 18–50%, in comparison to the same parameters obtained for the unmodified counterpart. [ABSTRACT FROM AUTHOR]

Syzgium cumini (L.) Skeels powder (S. cumini powder), also known as Jamun, is well-known for its various medical and health benefits. It is especially recognized for its antidiabetic and antioxidant properties. Thus, S. cumini powder is used in various industries, such as the food and cosmetic industries. In this work, the fruit of S. cumini was utilized; its seeds were extracted, dried, and ground into powder. The ground powders were subjected to various techniques such as physicochemical tests, Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD), particle size analysis, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and antioxidant analysis. From the physicochemical tests, it was revealed that the jamun seed filler contained cellulose (43.28%), hemicellulose (19.88%), lignin (23.28%), pectin (12.58%), and wax (0.98%). The FTIR analysis supported these results. For instance, a peak at 2889 cm−1 was observed and associated with CH stretching, typically found in methyl and methylene groups, characteristic of cellulose and hemicellulose structures. The XRD results demonstrated that the crystallinity index of the jamun seed filler was 42.63%. The particle analysis indicated that the mean (average) particle size was 25.34 μm. This observation was ensured with SEM results. The EDX spectrum results showed the elemental composition of the fillers. Regarding thermal degradation, the jamun seed filler had the ability to withstand temperatures of up to 316.5 °C. Furthermore, endothermic and exothermic peaks were observed at 305 °C and 400 °C, respectively. Furthermore, the antioxidant property of the powder displayed a peak scavenging activity of 91.4%. This comprehensive study not only underscores the viability of S. cumini powder as a sustainable and effective particulate filler in polymer composites but also demonstrates its potential to enhance the mechanical properties of composites, thereby offering significant implications for the development of eco-friendly materials in various industrial applications. [ABSTRACT FROM AUTHOR]

Agricultural residue-activated carbon and biochar, inexpensive and environmentally friendly adsorbent materials, have recently received significant research attention. This study investigated the potential use of oak cupules in activated carbon form to remove widespread heavy metals (Pb2+, Cu2+, and Ni2+) from wastewater. The oak-activated carbon was prepared from oak cupules and activated with phosphoric acid. Oak-activated carbon was characterized using FTIR, BET analysis, energy-dispersive X-ray spectrometry (EDS), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The Freundlich, Langmuir, and Temkin isotherm models were used to assess the equilibrium data. The impact of various parameters, including pH effect, temperature, adsorbent dose, and contact time, was estimated. The Freundlich model was the most agreeable with Pb2+ adsorption by oak-based activated carbon, and Langmuir was more compatible with Cu2+ and Ni2+. Under optimum conditions, the average maximum removal was 63% Pb2+, 60% Cu2+, and 54% Ni2+ when every ion was alone in the aqueous solution. The removal was enhanced to 98% Pb2+, 72% Cu2+, and 60% Ni2+ when found as a mixture. The thermodynamic model revealed that the adsorption of ions by oak-based activated carbon is endothermic. The pseudo-second-order kinetic best describes the adsorption mechanism in this study; it verifies chemical sorption as the rate-limiting step in adsorption mechanisms. The oak-activated carbon was effective in removing Pb2+, Cu2+, and Ni2+ from wastewater and aqueous solutions. [ABSTRACT FROM AUTHOR]

The vibrating superfine mill (VSM) is a machine that belongs to the micronization technique. In this study, VSM was employed to produce micronized tapioca starch by varying micronization times (15, 30, 45, and 60 min). The structural and physicochemical properties of the micronized starch were then examined. Scanning electron microscopy studies revealed that micronized starch was partially gelatinized, and the granule size dramatically increased when micronization time increased. X‐ray diffraction patterns showed that the relative crystallinity was decreased from 24.67% (native) to 4.13% after micronization treatment for 15 min and slightly decreased after that. The solubility of micronized starch significantly increased as the micronization time increased, which was associated with the destruction of the starch crystalline structure. Differential scanning calorimetry investigations confirmed that micronized starch was "partly gelatinized," and the degree of gelatinization increased to 81.27% when the micronization time was 60 min. The weight‐average molar mass was reduced by 15.0% (15 min), 30.9% (30 min), 55.7% (45 min), and 70.5% (60 min), respectively, indicating that the molecular structure was seriously degraded. The results demonstrated that the physicochemical changes of micronized starch granules were related to the destruction of the starch structure. These observations would provide details on micronized starch and its potential applications. Practical Application: These observations would provide details on micronized starch and its potential applications. Moreover, we believe that when the structures of starches were known, it is probable that the effect of VSM on the structural and physicochemical properties change of other starches might be predicted by adjusting the processing time. [ABSTRACT FROM AUTHOR]

The increasing concerns about health have led to a growing demand for high‐quality fried foods. The potential uses of Ligustrum robustum (Rxob.) Blume, a traditional tea in China, as natural additives to enhance the quality of starchy food during frying was studied. Results indicated that L. robustum polyphenols extract (LREs) could improve the quality of fried starchy food, according to the tests of color, moisture content, oil content, texture property, and volatile flavor. The in vitro digestion results demonstrated that LRE reduced the final glucose content from 11.35 ± 0.17 to 10.80 ± 0.70 mmol/L and increased the phenolic content of fried starch foods from 1.23 ± 0.04 to 3.76 ± 0.14 mg/g. The appearance and polarizing microscopy results showed that LRE promoted large starch bulges on the surface of fried starchy foods. Meanwhile, X‐ray diffraction results showed that LRE increased the intensity of characteristic diffraction peak of fried starch with a range of 21.8%–28%, and Fourier transform infrared results showed that LRE reduced the damage to short‐range order structure of starch caused by the frying process. In addition, LRE increased the aggregation of starch granules according to the SEM observation and decreased the enthalpy of starch gelatinization based on the differential scanning calorimetry results. The present results suggest that LREs have the potential to be utilized as a natural additive for regulating the quality of fried starchy food in food industries. Practical Application: The enhancement of L. robustum polyphenols on the quality of starchy food during frying was found, and its mechanisms were also explored. This work indicated that L. robustum might be used as a novel economic natural additive for producing high‐quality fried foods. [ABSTRACT FROM AUTHOR]

This study investigated a blend of poly (lactic acid) (PLA) and Saqqez gum, with a weight ratio of 70:30, respectively, along with two plasticizers, acetyl tributyl citrate (ATBC) and polyethylene glycol (PEG), at three different concentrations (14%, 16% and 18% by weight of the PLA). The blend was analyzed using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), tensile tests, water-absorption behavior (coefficients of water absorption, sorption, diffusion and permeability of the samples during 240 h) and chemical resistance (exposure to 1 mol/L HCl and 1 mol/L NaOH for 240 h). The desired elastomer blend was then used to prepare natural chewing gum, which was subsequently subjected to texture profile analyzer (TPA) tests and sensory evaluation. The results showed that the addition of both plasticizers increased the tensile properties of the blend. Compared to neat PLA, all the blends exhibited an increase in elongation at break and a decrease in yield strength, with the maximum elongation at break (130.6%) and the minimum yield strength (12.2 MPa) observed in the blend containing 16% ATBC. Additionally, all the thermal attributes studied, including Tg, Tc and Tm, were lower than those of neat PLA, and the Tg values deviated from the values predicted via Fox's equation. SEM images of the blends confirmed that plasticization improved the homogeneity and distribution of the components in the blend structure. PEG 18% and ATBC 16% exhibit the highest and lowest water-absorption behavior, respectively. Regarding chemical resistance, all blends showed weight gain when exposed to HCl, while no weight loss was observed for resistance to NaOH. The chewing gum sample obtained similar values for the mentioned tests compared to the commercial control sample. Overall, the results indicate that plasticization enhances the structure and performance of the PLA/Saqqez gum blend and further investigation is warranted. [ABSTRACT FROM AUTHOR]

In recent years, conductive polymer nanocomposites have gained significant attention due to their promising thermoresistive and Joule heating properties across a range of versatile applications, such as heating elements, smart materials, and thermistors. This paper presents an investigation of semi-crystalline polyvinylidene fluoride (PVDF) nanocomposites with 6 wt.% carbon-based nanofillers, namely graphene nanoplatelets (GNPs), multi-walled carbon nanotubes (MWCNTs), and a combination of GNPs and MWCNTs (hybrid). The influence of the mono- and hybrid fillers on the crystalline structure was analyzed by X-ray diffraction (XRD) and differential scanning calorimetry (DSC). It was found that the nanocomposites had increased amorphous fraction compared to the neat PVDF. Furthermore, nanocomposites enhanced the β phase of the PVDF by up to 12% mainly due to the presence of MWCNTs. The resistive properties of the nanocompositions were weakly affected by the temperature in the analyzed temperature range of 25–100 °C; nevertheless, the hybrid filler composites were proven to be more sensitive than the monofiller ones. The Joule heating effect was observed when 8 and 10 V were applied, and the compositions reached a self-regulating effect at around 100–150 s. In general, the inclusion in PVDF of nanofillers such as GNPs and MWCNTs, and especially their hybrid combinations, may be successfully used for tuning the self-regulated Joule heating properties of the nanocomposites. [ABSTRACT FROM AUTHOR]

Objectives: Conventional hair permanent waving (PW) and permanent straightening processes typically involve two steps: reduction, for breaking ‐S‐S‐ bond in cystine into cysteine and oxidation for ‐S‐S‐ bond reconnection. However, it is known that the hair incurs damage during the oxidation step. In this work, we proposed a novel strategy to reconnect reduced disulfide bonds in hair via the thiol‐Michael click reaction, by using a symmetric Michael reagent. Methods: Virgin black Chinese hair was reduced using 8% wt thioglycolic acid and employed as model hair containing a high content of broken disulfide bonds. The reduced hair was treated with 1,4‐n‐butylene dimaleate. Raman spectroscopy and Fourier transform infrared spectroscopy (FT‐IR) were used to verify the chemical changes occurred in untreated and treated hair fibre. Single‐fibre mechanical properties and thermal properties of the hair were evaluated using tensile testing and differential scanning calorimetry (DSC), respectively. Results: The 1,4‐n‐butylene dimaleate could reconnect free thiol groups generated by disulfide bond reduction via thiol‐Michael click reaction and significantly improve the mechanical strength of hair compared to that of the reduced hair. Secondary conformational resolution analysis of FT‐IR results revealed that the content of α‐helix structure could be restored after treatment with 1,4‐n‐butylene dimaleate. The intermolecular forces established by the newly generated C‐S bonds compensate the broken disulfide bonds and enhance the fracture strength of the hair compared to that of reduced hair. Michael reagents of similar structure also showed similar performance in restoring the mechanical properties of reduced hair. Conclusions: Our data suggest that 1,4‐n‐butylene dimaleate can restore the mechanical properties of reduced hair by reconnecting reduced disulfide bonds and restoring the secondary conformation of hair keratin. [ABSTRACT FROM AUTHOR]

Objective: Hair ageing is accompanied by hair fibres becoming irregularly shaped causing them to stick out in irregular directions or have more curliness and being spread out. This is believed to be due to changes within the hair fibre structure which occur with ageing, and one of the causes of these changes could be an increase in the number of protein carbonyl groups present in the hair. The aim of this study is to investigate the internal denaturation of hair related to protein carbonyls in attempt to gain new insight into age‐related changes that occur in hair. Methods: The degree of carbonylation of the hair structural protein as determined by fluorescent labelling and Western blotting analysis was used to investigate the primary structure of hair protein. The amount of helix, a common conformation in the secondary structure of proteins, in hair in groups of women with different ages was also analysed using infrared microscopy coupled with multivariate curve resolution (MCR). From the results of this, an image of the two‐dimensional distribution of the α‐helices was generated for the hair taken from each age group. Also, high‐pressure differential scanning calorimetry (HPDSC) of the hair in water was performed on the hair taken from each age group to determine the peak temperature of endothermic effect and the enthalpy of denaturation. Results: We found that the amino group content in hair proteins decreased and Type II keratin, one of the subunits of intermediate filament, was more carbonylated with age. The results of the MCR indicated eight separate components, including components of the secondary structure of proteins, such as α helices and β sheets. Two‐dimensional images of the hair cross‐sections revealed that the presence of α helices decreased with age. In addition, data from the HPDSC showed that the enthalpy associated with the denaturing temperature also significantly decreased with age. Conclusion: These results suggest that there is a negative correlation between age and structural integrity of the helix segment in intermediate filament. The results of this study also show that there is a positive correlation between age‐related hair denaturation and protein carbonyls. [ABSTRACT FROM AUTHOR]

Thermoresponsive drug delivery systems have been used to treat diseases that cause hyperthermia or elevated body tissue temperatures, viz., rheumatoid arthritis and different cancers. The aim of the study was to enhance berberine (BER) release using thermosensitive nanostructured lipid carriers (TNLCs) through intra-articular administration for the management of arthritis. TNLCs were prepared using binary mixtures of stearic acid and decanoic acid as solid and liquid lipids, respectively. Lipid mixtures with an optimum melting point were assessed using differential scanning calorimetry studies. In vitro characterization of the BER TNLCs included particle size, zeta potential, entrapment efficiency, and drug release at 37 °C and 41 °C. Joint diameter measurement, real-time polymerase chain reaction (RT-PC) analysis, enzyme-linked immunosorbent assay (ELISA) for inflammatory markers, and histological evaluation of the dissected joints were all performed in vivo on rats with adjuvant-induced arthritis. In vitro characterization revealed negatively charged BER-loaded TNLCs with a spherical shape, particle size less than 500 nm, BER entrapment efficiency up to 79%, and a high drug release rate at an elevated temperature of 41 °C. In silico studies revealed the affinity of BER to different formula components and to the measured biomarkers. In vivo assessment of the optimum TNLCs showed that BER TNLCs were superior to the BER solution suspension regarding their effect on inflammatory biomarkers, joint diameter, and histological studies. [ABSTRACT FROM AUTHOR]

Recently, we applied solution 2H-nuclear magnetic resonance spectroscopy (2H NMR) to analyze the water (deuterium oxide, D2O) structure in several biopolymers at ambient temperature. We established that polymers with good blood compatibility (i.e. poly(2-methoxyethyl acrylate) (PMEA)) have water observed at high magnetic fields (upfield) compared with bulk water. Polymers containing poly(propylene glycol) (PPG) or poly(propylene oxide) (PPO) exhibit good compatibility; however, the reason for this remains unclear. In addition, reports on the blood compatibility of PPO/PPG are limited. Therefore, PPG diester (PPGest) was prepared as a model polymer, and its blood compatibility and water structure were investigated. PPGest exhibited excellent blood compatibility. The water in PPGest was observed upfield by 2H NMR, and it was defined as non-freezing water via differential scanning calorimetry. Based on these observations, the relationship between the blood compatibility and water structure of PPGest is discussed by comparing with those of PMEA, and the reason for the good performance of PPG/PPO-based polymers is discussed. [ABSTRACT FROM AUTHOR]

This study reports the fabrication of quartz fabric reinforced phthalonitrile composite possessing good thermal and wave-transmitting properties. Phthalonitrile-terminated oligomer PN-SF curing behavior was investigated using differential scanning calorimetry (DSC) and dynamic rheological analysis (DRA), revealing a good processability pre-curing temperature of only 175°C. The thermoset exhibited the 5% loss temperature about 462°C, and after the temperature rising to 400°C and 400°C/2 h aging, the weight loss was only 10%, indicating that the resulting thermoset possessed outstanding thermal property. Moreover, the resulting thermosets possessed extremely high glass transition temperature (Tg) about 420°C. Besides, the quartz fabric/phthalonitrile composite possessed extremely excellent mechaical properties. Importantly, the transmission efficiencies can reach 87% at a certain frequency at the incident angle of 0°∼35°, indicating its well waving-transmitting performance. Meanwhile, the composite exhibited stable and relatively low dielectric constant and dielectric loss at the range of 12∼18 GHz. This study can serve as a basis for rapid evaluation of the high heat resistance and waving-transmitting phthalonitrile resin-based composite in various application environments. [ABSTRACT FROM AUTHOR]

The quality 2-amino-5-chloropyridinium 4-aminobenzoate (2A5ClP4AB) single crystals were grown in methanol solvent by employing the solvent evaporation technique. The stoichiometry ratio of 2A5ClP4AB was confirmed by microanalysis. The melting point, decomposition, crystalline phase, purity, and specific heat capacity of 2A5ClP4AB crystal were explored by thermogravimetric-differential thermal analyses (TG–DTA), differential scanning calorimetry (DSC), and modulated scanning calorimetry (MDSC) methods. The various dielectric properties of 2A5ClP4AB single crystal concerning temperature and frequency were examined by dielectric measurements. The nonlinear optical (NLO) parameters such as dipole moment, polarizability, first-order hyperpolarizability, and second-order hyperpolarizabilities of the 2A5ClP4AB molecule were computed using density functional theory (DFT) by utilizing the Gaussian 09 program. The figured HOMO–LUMO energies of 2A5ClP4AB demonstrate the occurrence of a charge transfer mechanism, whereas the MESP map illustrates how various molecular interactions took place in it. Hirshfeld surface analyses helped to decode the nature of the interactions and packing structure of the crystals. The above studies were intended to explore the structural, thermal, electrical and NLO properties of 2A5ClP4AB and also to strengthen its effectiveness for optoelectronic and frequency conversion applications. [ABSTRACT FROM AUTHOR]

The addition of metals or metal oxides (MOs) into polypyrrole (PPy) could facilitate the effective incorporation of the features of a parent component into novel nanocomposites. As such, this present study used in-situ ultrasonic-assisted chemical oxidative polymerisation (in-situ UA-COP) to synthesise MO-PPy nanocomposites using titanium dioxide (TiO2), zinc oxide (ZnO), and silicone dioxide (SiO2). The impact of MOs on the structural, morphological, thermal and electrical characteristics of the fabricated nanocomposites was then methodically analysed. The nanocomposites' structural and chemical constitutions were ascertained by way of X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy. The MOs were incorporated via non-covalent bonds into the PPy matrix, without significantly affecting the PPy matrix. Thermogravimetric (TGA) and differential scanning calorimetry (DSC) analyses demonstrated that TiO2-PPy was the most thermally stable, rending it is ideal for use in reactions that require high resistance to temperature. It also had the highest electrical conductivity (2.48 S/cm), which could be attributed to the conductive channels that the MO nanoparticle interconnections formed within the polymer matrix. This in-depth investigation serves to disclose the effect of different MOs on the characteristics of PPy nanocomposites. The findings of this present study also highlight the potential applications of the produced PPy nanocomposites in different fields, especially for use in sensors. [ABSTRACT FROM AUTHOR]

Poly(lactide acid) (PLA) foams have shown considerable promise as eco-friendly alternatives to nondegradable plastic foams, such as polystyrene (PS) foams. Nevertheless, PLA foam typically suffers from low heat-resistance and poor cellular structure stemming from its inherent slow crystallization rate and low melt strength. In this study, a high-performance PLA foam with well-defined cell morphology, exceptional strength and enhanced heat-resistance was successfully fabricated via a core-back microcellular injection molding (MIM) process. Differential scanning calorimetry (DSC) results revealed that the added hydrazine-based nucleating agent (HNA) significantly increased the crystallization temperature and accelerated the crystallization process of PLA. Remarkably, the addition of a 1.5 wt% of HNA led to a significant reduction in PLA's cell size, from 43.5 µm to 2.87 µm, and a remarkable increase in cell density, from 1.08×107 cells/cm3 to 2.15×1010 cells/cm3. This enhancement resulted in a final crystallinity of approximately 55.7% for the PLA blend foam, a marked improvement compared to the pure PLA foam. Furthermore, at 1.5 wt% HNA concentration, the tensile strength and tensile toughness of PLA blend foams demonstrated remarkable improvements of 136% and 463%, respectively. Additionally, the Vicat softening temperature of PLA blend foam increased significantly to 134.8 °C, whereas the pure PLA foam exhibited only about 59.7 °C. These findings underscore the potential for the preparation of lightweight injection-molded PLA foam with enhanced toughness and heat-resistance, which offers a viable approach for the production of high-performance PLA foams suitable for large-scale applications. [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]

Lipoic acid trisulfide, a sulfane sulfur-containing trisulfide of α-lipoic acid, holds promise in pharmaceuticals, yet knowledge gaps persist regarding its synthesis, properties, and stability. Here, we synthesized the lipoic acid trisulfide with a purity exceeding 99% from α -lipoic acid on a gram scale and obtained novel β - cyclodextrin clathrates (84%-95% yield). Differential scanning calorimetry confirmed the inclusion of lipoic acid trisulfide in β-cyclodextrins. The resulting β-cyclodextrin clathrates exhibited significant improvements in water solubility and thermal stability. This pioneering study demonstrated a novel approach to the practical preparation of trisulfide and its β-cyclodextrin clathrates as active ingredients, paving the way for clinical development. [ABSTRACT FROM AUTHOR]

Repercussion of overutilizing the fossil fuels and petrochemicals resulted in global warming and polluted environment. Hence, in the quest for alternative sources of raw materials for developing greener adhesives, renewable and natural polymers like polysaccharides have a huge potential. In particular, the traditional water-based emulsion wood adhesive employs colloid-like polyvinyl alcohol for stabilizing polyvinyl acetate (PVAc) emulsion. Researchers have recently become interested in utilizing xanthan gum, a naturally occurring polymer, in place of stabilizers. Here, the effects of xanthan gum addition as a stabilizer for PVAc homopolymer-based wood adhesives on performance properties were investigated. Emulsion polymerization technique was employed to synthesize xanthan gum stabilized PVAc homopolymer emulsion. Hence, the present work investigates the applicability of xanthan gum added 0.5% and 1% as a colloid for the synthesis of PVAc wood adhesives. Effect of the addition of xanthan gum as a colloid on physical, thermal, and mechanical properties was studied by viscosity, pH, contact angle measurement, differential scanning calorimetry (DSC), and pencil hardness test of films. Emulsions in varying xanthan gum concentrations were prepared, and a universal tensile machine was utilized to measure the shear strength of the PVAc homopolymers applied to wood. As the concentration of xanthan gum increased, the adhesives' viscosity increased. The drastic increase in water resistance with increasing xanthan gum content was confirmed by water contact angle measurement. The use of xanthan gum improved the PVAc films' hardness as well. When compared to a pristine sample, the tensile shear strength with 1 wt% of xanthan increased by 50% after 6 h of bonding in dry environment and by 61% in wet conditions (as per EN 204). The study's overall conclusion highlights the enhanced adhesive performance of xanthan gum stabilized PVAc emulsion-based adhesives. [ABSTRACT FROM AUTHOR]

In this work, isotactic polypropylene (iPP) was modified with an organic phosphate salt nucleating agent LPN-9081 and CaCO3. The synergistic effect of LNP-9801 and CaCO3 in iPP was investigated using differential scanning calorimetry (DSC), scanning electronic microscope (SEM), and mechanical property tests. The DSC results showed that the peak crystallization temperature (Tc) of modified iPP was increased by about 10 °C when compared to that of pure iPP, this indicates that LNP-9801 and CaCO3 increased the crystallization rate of iPP. The mechanical property tests demonstrated significant improvements in bending modulus and impact strength of modified iPP (impact strength increased by 33.9%, flexural modulus increased by 100.1%), which achieved an optimal balance of stiffness and toughness. Furthermore, the SEM results indicated that LPN-9081 contributed to the good dispersion of CaCO3 in the iPP matrix. All of the above results show that organic phosphate salt nucleating agent LPN-9081 and CaCO3 had good synergistic effects in iPP. [ABSTRACT FROM AUTHOR]

The object of the present study is to develop a new controlled drug release system by loading quercetin into pluronic F127 micelles. For the experimental studies, first of all, the critical micelle concentration (CMC) of the pluronic F127 copolymer was found as 4.5% g/mL at 25 °C, since the micelle-forming surfactants formed micelles at concentrations equal to or higher than the CMC. Afterward, with thin-film hydration method, three micelle groups with different polymer/quercetin ratios were formed. In this procedure, pluronic F127 polymer dissolved in ethanol at 30–40 °C and different amount of quercetin was added to the polymer solution. The polymer-quercetin solutions were evaporated in the evaporator at 40 °C for 2 h to obtain a film. The resulting film was hydrated by adding of ultrapure water and the micelle suspensions were obtained after filtration. According to Malvern Zetasizer measurement and transmission electron microscope (TEM) analysis, quercetin loaded micelles were determined to have particle sizes between 40 and 50 nm. It was determined by fourier-transform infrared spectroscopy (FTIR) analysis that quercetin was physically found into pluronic F127 micelles without any chemical reaction. It was determined by X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analyzes that quercetin was present in amorphous form as a solid solution instead of in crystalline form in the micelles. Thermogravimetric analysis (TGA) analysis showed that loading quercetin into the micelles did not affect the thermal stability of the PF127 copolymer. The drug loading amounts for micelles were found between 1.95% and 3.3% (mg/mg) for different micelles groups and there was not much difference in the percentage of encapsulation efficiency values thought to the groups. In vitro release profiles of quercetin-loaded micelles were investigated in pH 7.4 phosphate buffer solution and at 37 °C. When the release results were examined in general, it was seen that the release rates of all formulations were almost the same after 168 h. The kinetic parameters of the release results of the micelles in different formulations were calculated according to the Peppas equation and it was determined that the quercetin release in each micelle formulation did not comply with Fick's law, according to the calculated n parameter. Quercetin-loaded polymeric micelles obtained in this study offer advantages due to their easy synthesis methods and slow release profiles and they can used to successfully encapsulation of hydrophobic active ingredients like quercetin. [ABSTRACT FROM AUTHOR]

Objective(s): Currently, the most important treatment approach for hemophilia type A is recombinant Factor VIII. However, due to its low retention time in the blood, the patients usually need successive injections. In addition, neutralization of injected proteins by antibodies complicates treatment. We examined the prolongation of the persistence time of injectable FVIII in the blood and the potential effects on survival using promising PEGylated liposomes (PEGLip) utilizing hydrogenated soy phosphatidylcholine (HSPC, Tm= 54.5 °C) and 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC, Tm= - 2 °C). Materials and Methods: Nanoliposomes with different percentages of PEG (3% and 5%) were obtained via the thin film hydration procedure and extrusion. Liposomal FVIII formulation was prepared and characterization was done. Results: The results revealed that the formulations are in the 80-120 nm range with uniform dispersion, which was confirmed using transmission electron microscopy (TEM) imaging. The phase transition temperature (Tm) of the liposomes was obtained by differential scanning calorimetry (DSC). With an attachment efficacy of approximately 87%, proteins bind non-covalently yet with a strong affinity to the exterior of PEGLip. The final formulations underwent additional examination. No significant change was observed in size, charge, and PDI between the FVIII-conjugated liposomal formulations and their liposomal nanoparticles. The selected formulations were injected into BALB/c mice. The circulation time and potential clotting effectiveness of PEGLip-FVIII are vastly improved over free protein, in non-hemophilic mice. Conclusion: The obtained results showed that using phospholipids with high Tm (HSPC) can improve the hemostatic efficiency of liposomes more than phospholipids with low Tm (POPC). [ABSTRACT FROM AUTHOR]

High thermostability and catalytic efficiency of α-amylase are required for the industrial applications. To improve catalytic parameters including Michaelis constant, maximum velocity, turnover number, enzyme half-life, and the catalytic efficiency of α-amylase, it was treated alone and/or simultaneously with Ca2+ ions (12.5 and 25 mM) and/or ultrasound (USN) (64.5 W, 25 + 40 kHz). The structural analysis of the enzyme (the enzyme's secondary structure and conformation) was carried out using Fourier transform infrared (FTIR) spectroscopy and circular dichroism (CD) techniques. Moreover, the thermal properties of the enzyme were evaluated using differential scanning calorimetry (DSC). USN + 12.5 mM Ca2+ and 25 mM Ca2+, changed the maximum velocity (+ 6.5% and + 37.4%), turnover number (+ 6.6% and + 38.2%), enzyme half-life (+ 51.6% and + 113.7%), and catalytic efficiency (+ 18.1% and -3.3%) of α-amylase. The energy barriers of thermo-inactivation and inactivation enthalpy of α-amylase exposed to USN + 25 mM Ca2+ were increased by 25% and 5.8%, respectively, without affecting entropy of inactivation, showing how enzyme's thermal stability was improved after the treatments. The increase in midpoint temperature (35%) and α-helix (14%) values as well as the decrease in the β-sheet structure (39%) of the α-amylase after applying USN + Ca2+ (25 mM) confirmed the thermal stability enhancement of α-amylase after the treatment compared to control. [ABSTRACT FROM AUTHOR]

In this study chitosan (CS) films were prepared from a deep eutectic solvent (DES) composed of choline chloride and malonic acid by solvent casting, and the influence of DES content on the structure and properties of the CS films was investigated in detail. It was confirmed by the spectral data that hydrogen bonds and ionic bonds were formed between the CS chains and DES. Structural analysis demonstrated that the crystallization of the CS was greatly hampered and the CS chains were stacked disorderly in films with high DES content. Differential scanning calorimetry (DSC) results indicated that DES exerted a significant plasticizing effect. In the case of the plasticized film containing 80 wt% of DES it showed a low glass transition temperature (Tg) of 20 °C. With increasing DES content, the water content of the plasticized films also increased, evidenced by the TGA results. Meanwhile, a structural change from granular to lamellar structure was observed by SEM. In addition, compared with pure CS film, the DES plasticized CS films possessed good fracture toughness and hydrophilicity. These observations suggest that the structure and properties of the CS films can be controlled by changing their DES content. [ABSTRACT FROM AUTHOR]

Background and Aims Orchid seeds are reputed to be short lived in dry, cold storage conditions, potentially limiting the use of conventional seed banks for long-term ex situ conservation. This work explores whether Cattleya seeds are long lived or not during conventional storage (predried to ~12 % relative humidity, then stored at −18 °C). Methods We explored the possible interaction of factors influencing seed lifespan in eight species of the genus Cattleya using physiological (germination and vigour), biochemical (gas chromatography), biophysical (differential scanning calorimetry) and morphometric methods. Seeds were desiccated to ~3 % moisture content and stored at −18 °C for more than a decade, and seed quality was measured via three in vitro germination techniques. Tetrazolium staining was also used to monitor seed viability during storage. The morphometric and germination data were subjected to ANOVA and cluster analysis, and seed lifespan was subjected to probit analysis. Key Results Seeds of all Cattleya species were found to be desiccation tolerant, with predicted storage lifespans (P 50y) of ~30 years for six species and much longer for two species. Cluster analysis showed that the three species with the longest-lived seeds had smaller (9–11 %) airspaces around the embryo. The post-storage germination method impacted the quality assessment; seeds equilibrated at room temperature for 24 h or in 10 % sucrose solution had improved germination, particularly for the seeds with the smallest embryos. Chromatography revealed that the seeds of all eight species were rich in linoleic acid, and differential scanning calorimetry identified a peak that might be auxiliary to selecting long-lived seeds. Conclusions These findings show that not all orchids produce seeds that are short lived, and our trait analyses might help to strengthen prediction of seed longevity in diverse orchid species. [ABSTRACT FROM AUTHOR]

A new single crystal of p-aminomethylbenzoicdichloride hydrate C8H10NO2·Cl·H2O (Compound1) was obtained by slow evaporation. The structure was investigated by single-crystal X-ray diffraction which revealed that they crystallize in monoclinic, P2/c system space group and unit cell parameters: (a = 15.957(5) Å, b = 4.823(5) Å, c = 12.154(5) Å, β = 107.562(5)° and Z = 4). The asymmetric unit consisted of a combination of a chlorine ion−anion, one structural water molecule H2O and an organic cation [+NH3–CH2–C6H4CO2H]. The structural integrity is upheld through an intricate three-dimensional hydrogen network, serving as a stabilizing force for the crystal lattice. The cohesion between organic chain and chlorine Cl− anion and H2O molecule is assured by π-stacking and hydrogen bonds interactions N–H...Cl, N–H...OH2 and C=O...H–O–C. The interaction has been thoroughly examined using Hirschfeld surface analysis. Furthermore, we employed density functional theory calculations to optimize the molecular structure. The micro-Raman spectroscopy measurements were taken to elucidate the vibration modes exhibited by the compound. Additionally, the material characteristic was probed using a deferential scanning calorimetry. [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]

This study aimed at developing and optimizing the orally dispersible thin film (ODTF) containing a plant-derived drug—curcumin (CUR). CUR belongs to a biopharmaceutical classification system (BCS) class IV compound that requires improving its water solubility and tissue permeability preceding formulation. An ODTF was applied to produce a solid dispersion matrix for CUR to resolve such solubility and permeability problems. The film-forming polymers used in the study were cellulose-based (hydroxypropyl methylcellulose/HPMC and carboxymethylcellulose/CMC) and saccharide-based maltodextrin (MDX). Poloxamer (POL) was also employed as surfactant and solubilizer. The solvent casting technique was applied to produce the films. The ethanolic solution of CUR was mixed with an aqueous solution of POLs and then incorporated into different film-forming polymers prior to casting. The processing of the CUR with POL solution was intended to aid in the even dispersion of the drug in the polymeric matrices and enhance the wettability of the films. The physical state and properties of the films were characterized in terms of their morphology, crystallinity of the drug, and phase miscibility of the mixtures. The dissolution profile of the films was also evaluated in terms of dissolution rate and dissolution efficiency. The obtained ODTF products were smooth and flat-surfaced. Physical characterization also indicated that the CUR was homogeneously dispersed in the ODTFs and no longer existed as crystalline material as revealed by X-ray diffraction (XRD). The CUR was also not phase-separated from the films as disclosed by differential scanning calorimetry (DSC). Such dispersion was achieved through the solubilizing effect of POLs and compact polymeric film matrices that prevented the CUR from recrystallization. Furthermore, the ODTFs also improved the dissolution of CUR by 3.2-fold higher than the raw CUR. Overall, cellulose-based films had favorable physical properties compared with saccharide-based films. [ABSTRACT FROM AUTHOR]

As an orally effective benzimidazole anthelmintic agent, fenbendazole was not only widely used in agriculture and animal husbandry to prevent and treat parasites, but also shows anti-cancer effects against several types of cancer, exhibits anti-cancer effects in paclitaxel and doxorubicin-resistant cancer cells. However, fenbendazole's poor in water solubility (0.3 µg/mL), limits its clinical applications. Even great efforts were made toward increasing its water solubility, the results were not significant to reach anti-cancer drug delivery requirement (5–10 mg/mL). Through single factor and orthogonal strategy, many complex conditions were designed and used to prepare the complexes, the inclusion complex with methyl-β-cyclodextrin with 29.2 % of inclusion rate and 89.5% of inclusion yield can increase drug's water solubility to 20.21 mg/mL, which is the best result so far. Its structure was confirmed by differential scanning calorimetry, scanning electron microscopic image, 1D and 2D NMR spectra in D2O. In its in vitro pharmacokinetic study, fenbendazole was 75% released in 15 min., in its in vivo pharmacokinetic study, the bio-availabilities of fenbendazole, its major metabolic anthelmintic agent oxfendazole and its minor metabolic anthelmintic agent oxfendazole were increased to 138%, 149% and 169% respectively, which would allow for fewer drug doses to achieve the same therapeutic effect and suggest that the complex can be used as a potential anticancer agent. [ABSTRACT FROM AUTHOR]