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Polylactic acid/chitosan (PLA/CS) and poly(vinyl alcohol)/chitosan (PVA/CS) are considered potential blends for use in tissue engineering, since when obtained in the form of 3D fibers they can form structures with high porosity, biocompatibility, antimicrobial activity and morphology similar to tissues and organs. However, there is a scarce number of reports in the literature addressing the production of systems based on 3D fibrous mixtures of PVA or PLA with high chitosan amount because of the difficulty in spinning CS into stable structures using acidic solutions, and without further employment of cross-linking agents. Therefore, this work focused on a novel procedure to prepare 3D fibrous structures of PVA and PLA with high chitosan content, combining the solution blow spinning technique, a heated air environment and the use of eco-friendly solvents, without using crosslinking agents. The influence of CS incorporation on the as-prepared structures was assessed by scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction, contact angle measurement, porosity, swelling and degradation tests. Rheological tests evidenced that an increase in the CS content implies a greater viscosity of the spinning solutions, hindering the fibrillar structures formation. Fibers produced showed a randomly interconnected and highly porous fibrous cotton-wool-like structure, with fiber diameters ranging from 481 to 637 nm for PVA/CS systems, and from 1276 to 2050 nm for PLA/CS systems. A decrease in the thermal stability of the blend-based fibers and an increase in hydrophilicity, porosity, swelling and in vitro biodegradation were observed in the blend systems. Results indicate that the obtained fibrillar structures possess morphological and physical characteristics that may be interesting for application as 3D fibrous scaffolds in tissue engineering. [ABSTRACT FROM AUTHOR]

Purpose: Astaxanthin (AX), commonly used for dermal applications, exhibits anti-inflammatory and antioxidant activities; however, it has poor water solubility. In this study, we investigated the physicochemical properties of AX-containing particulates formulated using the amphiphilic graft copolymer Soluplus (polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer: Sol) and polyethylene glycol-2000 (PEG 2000); in addition, the stability and skin applications of AX particulates were investigated. Methods: AX, Sol, and PEG were mixed by weight to prepare AX particles using the hydration method. The prepared particles were subjected to stability evaluations including particle size distribution, zeta potential estimation, and fluorescence spectroscopy as well as physical evaluations including 1H-1H NOESY NMR spectral measurement, powder X-ray diffraction, and differential scanning calorimetry. Functional evaluations included singlet oxygen scavenging, skin permeation test, and fluorescence microscopy. Results: Relatively stable particles of Sol/AX and Sol/PEG 2000/AX, approximately 100 nm and 125 nm in size, respectively, were formed at a mixed weight ratio (9/1) of 0.1 M Ascorbic Acid solution (0.1 M ASC) and a mixed weight ratio (8/1/1) of 0.1 M ASC, respectively, at 25 °C after storage for 14 days under light-shielded condition. Stability evaluations revealed a decrease in fluorescence intensity and color fading for Sol/AX = 9/1 and Sol/PEG 2000/AX = 8/1/1 (dispersion medium: distilled water); however, no change in fluorescence intensity of AX was observed immediately after preparation in Sol/AX = 9/1 and Sol/PEG 2000/AX = 8/1/1 (dispersion medium: 0.1 M ASC). The fluorescence intensity of AX did not fluctuate significantly immediately after adjustment, and the particles remained stable, showing a bright orange color with time. NMR spectra of Sol/AX = 9/1 and Sol/PEG 2000/AX (dispersion medium: 0.1 M ASC) showed the interactions between the CH3 group e from Sol (1.8 ~ 2.0 ppm) and the CH groups H-15,11 from AX (6.7 ~ 6.8 ppm), 8',12' (6.4 ~ 6.5 ppm), H-10,14 (6.4 ~ 6.5 ppm), and 7,7' (6.2 ~ 6.3 ppm), indicating the disappearance of cross peaks. Furthermore, new cross peaks were identified for the CH3 group e of Sol (1.8 ~ 2.0 ppm), the 7-membered ring z of Sol (1.5 ~ 1.8 ppm), the 5-membered ring S of ASC (3.5 ~ 3.6 ppm), the CH group T (3.8 ~ 3.9 ppm), and the CH group U (4.7 ppm). Fluorescence microscopy observations of microparticles formulated with Sol/PEG 2000/AX showed a slight improvement in skin penetration. Conclusion: New AX particulates were formed using Sol/PEG 2000/AX = 8/1/1, suggesting that Sol/PEG 2000/AX maintained the stability and improved the skin penetration of AX. [ABSTRACT FROM AUTHOR]

Synthesis, structural and photoluminescence studies of p-(n-heptyl) benzoic acid (7ba) liquid crystalline (LC) compound with the homogeneous dispersion of ZnO nanoparticles (NPs) in different weight concentrations (i.e., 1–2.5 wt.%) were undertaken. The synthesized samples were subsequently characterized by different characterization techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible (UV-Vis) spectroscopy, differential scanning calorimetry (DSC), optical polarising microscopy (POM), Fourier transform infrared spectroscopy (FT-IR), and photoluminescence (PL) spectroscopy. From the XRD studies, the diff raction peaks observed were well resolved indicating the presence of ZnO NPs. The particle size was found to be 60 nm. SEM studies revealed the uniform dispersion and the presence of ZnO NPs in the LC samples. From the DSC analysis, the temperatures at which the phase changes take place and the corresponding enthalpy values were estimated. FTIR spectra gave information about the various functional groups present in the samples. PL studies showed the peak at 663 nm due to the presence of point defects within the bandgap-like vacancies and interstitials known as deep-level emission. [ABSTRACT FROM AUTHOR]

Polypropylene multifilament yarns produced with flame-retardant (FR) additives have a significant place in the technical textile market. Determination of the technical performances of these multifilaments is very important. In addition, effects of the additive in the filament structure on the thermal and structural properties of the filament must be examined. In this study, new polypropylene polymer (PP) filament yarns having FR properties were produced and their thermal properties and crystallization data were determined and results are interpreted. Thermal properties and crystallization data of the PP multifilament yarns were determined by DSC analysis. Further, values of crystalline region ratio were determined and thermogram graphs of all samples were interpreted. As can be seen from the graphs, PP filaments had two consecutive melting points because PP has a double melting peak due to its structural character. Also, it has been observed that there is a direct proportionality between the melting enthalpy values of PP filaments and crystalline region ratios (%). The melting point was not significantly affected by the amount of FR additive. The addition of FR granule to PP filament further increases the enthalpy (∆Hm) required to melt the filament but there was no effect on melting temperature due to loading of FR additive to the PP filament yarns. Also, mechanical properties (tenacity and breaking elongation) and unevenness values were determined. [ABSTRACT FROM AUTHOR]

Research on the digestion kinetics of gibbsite in the Bayer process contributes to understanding the reaction mechanism and promoting the reaction process. In this work, the non-isothermal kinetics of synthesized pure gibbsite digestion in NaOH solution was studied at the heating rates of 2.5 K min−1, 5 K min−1, 7.5 K min−1, and 10 K min−1 by high-pressure differential scanning calorimetry (HP-DSC). The apparent activation energy was calculated using the Ozawa method and the Kissinger method, then the most probable mechanism function of the reaction was determined using the Coats–Redfern method. The apparent activation energies calculated from the Ozawa and Kissinger methods were 62.56 kJ mol−1 and 61.86 kJ mol−1, respectively, indicating that the digestion of gibbsite was controlled by chemical reactions. The integral and differential forms of the most probable mechanism function were G(α) = 1 − (1 − α)1/3 and f(α) = 3(1 − α)2/3, which accorded with systolic spherical models. Furthermore, the kinetics equation of the gibbsite digestion in NaOH solution has been proposed. [ABSTRACT FROM AUTHOR]

The solution casting method was used to synthesize nanocomposites of polymethyl methacrylate (PMMA) and polystyrene (PS) polymer with graphene oxide (GO). It was determined that the conductivity of the PS/GO and PMMA/GO polymer nanocomposites was ionic and electronic, respectively. The thermal conductivity of the nanocomposites was investigated with regard to the impact of crystallinity and free volume. This paper reports a differential scanning calorimetric (DSC) study of PMMA/GO (1%) and PS/GO (1%) and nanocomposite blends of PMMA and PS prepared in different ratios by weight percentage of PMMA/PS (80:20, 60:40, 50:50, 60:40, 20:80) with 1% of GO using the solution casting method. The samples were analyzed using a DSC instrument at heating rates of 5°C/min, 10°C/min, and 20°C/min in the temperature range of 50–160°C. Fourier transform infrared (FTIR) spectroscopy and x-ray diffraction (XRD) studies of the blends showed that the crystalline phases of PS and PMMA depended on the GO percentage in the composite solutions. Significant shifts were seen in FTIR, XRD, and DSC analyses, and DSC and TGA thermograms of the nanocomposite blend confirmed the formation of a PS/PMMA blend and demonstrated a significant change in thermal behavior with the blend ratio. The activation of the pure and blended polymers was determined through their glass transition using different isoconversional methods. [ABSTRACT FROM AUTHOR]

Differential scanning calorimetry (DSC) is considered one of the most versatile thermal analysis tools for characterizing polymer samples. This paper reports a DSC study of blends of polymethyl methacrylate (PMMA) and polystyrene (PS) prepared in different ratios by weight percentage for all blend ratios used for PMMA:PS (80:20, 60:40, 50:50, 60:40, 20:80) using the solution cast method. The samples were analyzed at heating rates of 5°C/min, 10°C/min and 20°C/min in the temperature range of 50–200°C. The glass transition temperature (Tg) was theoretically calculated using Fox's equation for all the samples. It was found that the experimental glass transition temperature is very close to the theoretical values. DSC thermograms supported the confirmation of the formation of PS–PMMA blends and demonstrated a significant change in their thermal behavior with changes in blend ratio. The activation energy of crystallization was evaluated using both isokinetic and iso-conversional approaches, and similar findings were found. Using various iso-conversional approach models, the activation was determined for pure and blended polymers through their glass transition. Notably, the activation energy values obtained using different iso-conversional methods and specific iso-conversional techniques, such as Ozawa, Kissinger, Boswell, and Augis and Bennett, are relatively consistent. [ABSTRACT FROM AUTHOR]

PVA/AgNO3 composite films were prepared on fused silica substrates using a casting technique and irradiated with blue light to synthesize silver nanoparticles (AgNPs) within the polymer matrix. The physical and chemical properties of the films were analyzed, revealing increased crystallinity and the formation of Ag nanoparticles and nanorods after irradiation. FTIR spectra showed a vibrational band of Ag–O at 760 cm⁻1 after 30 min of irradiation. The absorption coefficient exhibited a transition band between 400 and 500 nm, with peak amplitude increasing with irradiation time, indicating more Ag nanostructure formation. Differential scanning calorimetry (DSC) analysis showed a rise in melting temperature from 62 to 84 °C and a decrease in crystallization temperature from 188 to 185 °C. Thermogravimetric analysis (TGA) indicated thermal stability with minor mass loss up to 270 °C. Electrical conductivity increased from 2.29 to 3.35 µS.cm⁻1 with increased blue light irradiation time. Our study documents the efficient synthesis of well-distributed AgNPs within the PVA matrix using blue light irradiation, which significantly enhances the optical, thermal, and electrical properties of the composite films. These improved properties make the films suitable for applications in sensors, flexible electronics, and antimicrobial coatings. [ABSTRACT FROM AUTHOR]

Polyvinylidene fluoride (PVDF) boosted its technological applications because of its piezoelectric and pyroelectric properties, together with mechanical, chemical, and thermal resistance. In this review, we address the PVDF chemical structure and its synthesis procedure, also describing the occurrence of polymorphism (alpha (α), beta (β), gamma (γ), and delta (δ) of this semicrystalline polymer, and the processes involved in phase transformation that govern the adaptability of the PVDF crystalline phases and properties for several industrial uses. It can be used as a component of implants and sutures, as engineering plastic to play a structural role in aggressive environments, acting in the field of process control as a component of transducers and sensors, as well as in the synthesis of separation membranes, fuel cells, and a long list of new applications that include an important role in robotics. The main physicochemical techniques used for PVDF characterization, i.e., differential scanning calorimetry, Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy, that highlight its unique properties, are also discussed, showing the versatility of PVDF for a range of biomedical and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Background: In advanced or metastatic cancers characterized by specific genetic alterations, heightened growth and resistance to conventional therapies are common. Targeted treatments like entrectinib (ENT) precisely inhibit aberrant signaling pathways, potentially enhancing outcomes. The objective of this research is to develop and enhance the effectiveness of entrectinib-loaded nanosponge formulations by utilizing hydroxypropyl-β-cyclodextrin (HPβCD) to improve its oral bioavailability. Results: The study employed surface response methodology and Design-Expert® software to optimize key formulation variables such as the molar concentration ratio of the polymer and cross-linker, as well as process variables such as stirring speed and duration. Optimization focused on particle size, polydispersity index, and percentage entrapment efficiency. Validation methods encompassed Fourier transform spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), in vitro release studies, and in vivo studies. After optimization, ENT-loaded HPβCD NSPs were formulated with a molar ratio (P:CL) of 0.800 mg, stirred at 3000 rpm for 420 min, achieving a desirability of 0.926. Predicted values for PS (particle size), PdI (polydispersity index), and EE % (entrapment efficiency) were 146.98 nm, 0.263, and 88.29%, respectively. The optimized formulation showed a mean size of 151.8 ± 5.6 nm, PDI of 0.233 ± 0.049, and EE of 87.36 ± 1.61%. Further validation through various analyses confirmed the optimization's efficacy, with notable improvements demonstrated in AUC0-t (6.30-fold) and Cmax (4.10 times) compared to the free drug. Conclusion: The findings of the study indicated that nanosponges exhibit promise as an effective carrier for delivering entrectinib, addressing for advance tumor effectively by enhancing release and bioavailability in the treatment of cancer. Highlights: Entrectinib (ENT) is an innovative and powerful inhibitor targeting specific genetic alterations in advanced or metastatic cancers. Preclinical investigations have shown strong suppression of receptor tyrosine kinases, such as TRKA/B/C and ROS1, at nanomolar (nM) concentrations using ENT. ENT is categorized under the Biopharmaceutical Classification Systems (BCS) II, with poor solubility and inadequate oral bioavailability. Formulation of ENT HPβCD based nanosponges (NSPs) present a compelling option for drug delivery due to their sustained drug release, enhanced stability, and significant carrying capacity. [ABSTRACT FROM AUTHOR]

This study introduces a novel microwave applicator and optimized processing conditions to enhance the stability of Polyacrylonitrile (PAN)-based precursor fiber (PF). The innovative microwave applicator facilitates the propagation of the electromagnetic (EM) field akin to a quasi-traveling wave, thus circumventing standing wave nodes. This ensures a uniform thermal distribution and broadens the heating zone. Utilizing this applicator, the PF undergoes thermal stabilization in a streamlined two-step process, completing in just 13 min, a significant improvement over the conventional 90-min process. This not only saves manufacturing time, promoting energy efficient manufacturing but also aligns with the global trend towards green energy and lightweight carbon fiber-reinforced polymer matrix composites, potentially catalyzing rapid economic growth. Fiber characterization through Raman spectroscopy (RS), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and complex permittivity measurements reveals that the microwave-processed fiber meets the standard of commercial stabilization fiber (SF). [ABSTRACT FROM AUTHOR]

The polyacrylonitrile multifilament yarn underwent a multistep heat treatment process including stabilization times ranging from 5 to 75 min following impregnation with a 30% ethylenediamine (EDA) aqueous solution. A series of measurements were employed to determine the structure and properties of thermally stabilized PAN samples. These included fiber thickness, fiber density, flame testing, tensile testing, X-ray diffraction, thermal analysis (differential scanning calorimetry and thermogravimetric analysis), and infrared spectroscopy. The results from XRD and IR spectroscopy indicated that the rate of aromatization reactions increased with longer stabilization times. A detailed examination of the XRD curves obtained through curve-fitting procedures suggested a rapid transformation of the original structure into a disordered amorphous phase containing pre-graphitic domains, evidenced by a gradual reduction in the degree of apparent crystallinity of the original PAN sample. The integration of EDA before the thermal stabilization stage significantly reduced the cyclization time of nitrile groups in the PAN polymer structure, thereby accelerating the stabilization reactions. This chemical pretreatment also improved the thermal stability of the samples by promoting oxidative cross-linking of the PAN polymer chains. After a 75 min multistep stabilization, the carbon yield at 1000 °C was 70.5%. Conversion index values, calculated using IR, XRD, and DSC methods, were 98.3%, 94.8%, and 89.5% respectively for the 75 min sample. These findings highlight the importance of EDA in accelerating the formation of an aromatic structure, which is critical for withstanding the high temperatures of subsequent carbonization stages. [ABSTRACT FROM AUTHOR]

Two series based on poly(propylene 2,5-furandicarboxylate)-block-poly(tetramethylene oxide) (PPF-b-F-PTMO) containing carbon and mineral nanofillers that differ in shape (1D and 2D) were synthesized via in situ polymerization. The influence of the addition of the 1D-type nanoparticle, i.e., carbon nanofibers (CNFs) and halloysite nanotubes (HNTs), and the so-called 2D-type, i.e., graphene nanoplatelets (GNPs) and organoclay (C20A), on the properties of a biobased block copolymer was analyzed. The dispersion of nanoadditives in the nanocomposites was determined using a scanning electron microscope (SEM). The thermal properties were studied employing differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The introduction of nanoparticles increased the crystallinity (Xc) and the mean values of tensile modulus (E) of the bionanocomposites. In turn, one observed that the decrease in the limited viscosity number (LVN) was visible along with incorporating nanoadditives. The synthesized polymer bionanocomposites reveal the mechanical properties of elastomers during mechanical testing. Moreover, the good processability of the obtained materials by injection molding combined with the comprehensive ability to change mechanical and thermal properties of PPF-b-F-PTMO by tailoring the type and content of the nanofillers can indicate their possible applications in packaging, automotive, sports, construction, and many other industries. [ABSTRACT FROM AUTHOR]

The limitations associated with conventional cancer treatment modalities, particularly for breast cancer, underscore the imperative for developing safer and more productive drug delivery systems. A promising strategy that has emerged is the combination of chemotherapy with gas therapy. We synthesized curcumin-loaded amorphous calcium carbonate nanoparticles (Cur-CaCO3) via a gas diffusion reaction in the present study. Subsequently, a "one-step" ethanol injection method was employed to fabricate lipid-coated calcium carbonate nanoparticles (Cur-CaCO3@LA-Lip) loaded with L-arginine, aimed at harnessing the synergistic effects of chemotherapy and nitric oxide to enhance antitumor efficacy. Transmission electron microscopy analysis revealed that Cur-CaCO3@LA-Lip nanoparticles were subspherical with a distinct lipid layer encapsulating the periphery. Fourier transform infrared spectroscopy, X-ray powder diffraction, and differential scanning calorimetry results confirmed the successful synthesis of Cur-CaCO3@LA-Lip. The nanoparticles exhibited significant drug loading capacities of 8.89% for curcumin and 3.1% for L-arginine. In vitro and in vivo assessments demonstrated that Cur-CaCO3@LA-Lip nanoparticles facilitated sustained release of curcumin and exhibited high cellular uptake, substantial tumor accumulation, and excellent biocompatibility. Additionally, the nanoparticles showed robust cytotoxicity and potent antitumor efficacy, suggesting their potential as a formidable candidate for breast cancer therapy. [ABSTRACT FROM AUTHOR]

In this work, the phase equilibria of the binary Ag-In system were determined using electron probe microanalysis and differential scanning calorimetry on equilibrated alloys and diffusion couples. The compositions of the phase boundaries of solid phases that are highly scattered in the literature have been precisely determined. The temperatures of the invariant reaction ζ ⇄ γ + L and the polymorphic transformation ζ ⇄ γ are substantially lower than previously reported values. In addition, it was found that the In-rich ζ phase phase-separates after months of room-temperature aging. [ABSTRACT FROM AUTHOR]

This article investigates the thermal, mechanical, and shape memory performances of 3D-printed polylactic acid (PLA), polyethylene terephthalate glycol (PETG), and their blends for potential applications in 4D printing. Differential Scanning Calorimetry reveals distinct glass transition temperatures for PLA-PETG blends, confirming their immiscibility. The integration of PETG alters the crystalline structure of PLA, shifting its behavior from brittle to ductile. This confirms PETG's function as an effective plasticizer. The tensile strength and Young's modulus are influenced by material composition and printing orientation. The results show that 75% PLA and 25% PETG blend demonstrated enhanced mechanical properties compared to other polymer blends. Shape memory experiments demonstrate exceptional fixity and recovery rates, reaching 100%, with the 75% PLA blend exhibiting outstanding performance across 15 cycles. These findings, coupled with insights into the impact of programming temperature, offer valuable perspectives for designing 4D-printed structures with shape memory attributes, unlocking innovative applications across diverse fields. [ABSTRACT FROM AUTHOR]

This study employed reactive extrusion to produce micro-composites of high-density polyethylene (HDPE) with different fractions of diatomaceous earth, both unmodified and modified, using a novel reversible crosslinking reaction agent (RXR) consisting of a combination of sulfur, organic peroxide, and an accelerator. The rheological behavior and crosslinking response of the system were measured using dynamic rheological analysis using a torque rheometer. The mechanical characteristics of the system were evaluated through tensile and impact tests. The thermal characteristics were analyzed using differential scanning calorimetry and thermogravimetric analysis, while the structural and morphological properties were analyzed using wide-angle X-ray scattering, Fourier infrared transform, and scanning electron microscope. The mechanical properties of the HDPE resin were diminished by the inclusion of the diatomaceous earth due to aggregation and inadequate interfacial connections, whereas the thermal stability remained unaffected. Furthermore, the presence of diatomaceous earth led to enhancements in both crystallinity and lamellar thickness. The addition of the RXR agent improved the tensile and impacts strengths, caused by the crosslinking reaction. However, it had a detrimental effect on the degree of crystallinity and the size of the crystals formed. Analysis of mechanical, rheological, and crystallization properties demonstrated that the incorporation of diatomaceous earth and the diatomaceous earth-RXR agent combination showed potential as additives for HDPE. [ABSTRACT FROM AUTHOR]

The characterization of the physicochemical properties of wheat flour and the rheological characteristics of dough is necessary to predict processing behavior, functionality, and end-product development. Differential scanning calorimetry, pasting analysis, FTIR spectroscopy, X-ray diffraction study, and rheological measurements were used to analyze the wheat flour of different cultivars. The thermal and pasting parameters varied significantly (p ≤ 0.05) among the cultivars and showed a negative correlation with amylose content. The FTIR spectra of all wheat flour showed a weaker intensity of absorption peak at 1540 cm–1 and 1420 cm–1 associated with amide II and amide III bands. The relative crystallinity showed a significant positive correlation with HPV and CPV (hot and cold paste viscosities) and a negative correlation with amylose content. The rheological characteristics were analyzed by amplitude sweep (AS), frequency sweep (FS), and creep-recovery test of dough. The AS/FS results showed a weak gel-like structure reflecting a more elastic nature than viscous behavior. Gʹ and Gʹʹ positively correlated with pasting viscosities i.e., peak (PV), CPV, and breakdown viscosities. Viscoelastic compliance (J1) of recovery showed a significant negative correlation with textural parameters, i.e., chewiness and gumminess. Principal component analysis (PCA) reflected 71% of the cumulative variance and PC1 accounted for maximum variance (34%) with PV, HPV, CPV, Tp (peak temperature), 1047/1022 cm–1, crystallinity, and G' as the main factors. [ABSTRACT FROM AUTHOR]

Polypropylene is commonly used as a binder for ceramic injection molding, and rapid cooling is often encountered during processing. However, the crystallization behavior of polypropylene shows a strong dependence on cooling rate due to its semi-crystalline characteristics. Therefore, the influence of cooling rate on the quality of final product cannot be ignored. In this study, the fast differential scanning calorimetry (FSC) test was performed to study the influence of cooling rate on the non-isothermal crystallization behavior and non-isothermal crystallization kinetics of a copolymer polypropylene (PP BC03B). The results show that the crystallization temperatures and crystallinity decrease as the cooling rate increases. In addition, two exothermic peaks occur when cooling rate ranges from 30 to 300 K·s-1, indicating the formation of another crystal phase. Avrami, Ozawa and Mo equations were used to explore the non-isothermal crystallization kinetics, and it can be concluded that the Mo method is suitable for this study. [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]

The material design concept of high-entropy alloy (HEA) is proposed for Tribaloy alloys. In this research, three HEAs are created by mixing Co-based T-800 and Ni-based T-700 Tribaloy alloys in different ratios and fabricated via spark plasma sintering (SPS) process. The phase transformation behavior of the mixed powders of T-800 and T-700 is investigated with differential scanning calorimetry (DSC) analysis. The microstructures of the SPS specimens and solidified DSC samples of the created HEAs are studied using SEM and XRD, showing that they consist of fcc Co, Mo, and Ni solid solution with minor hcp Co solid solution, various Laves phase, mainly Co3Mo2Si, CoMoSi, Ni3Mo2Si, Mo2Si, and CrSi2, and complex intermetallic compounds. The hardness and dry-sliding wear resistance of the created SPS HEAs are evaluated and compared with the initial alloys (T-800 and T-700). It is shown that the hardness and wear resistance of T-800 are much higher than that of T-700, which is attributed to the excellent properties of element Co; the created HEAs exhibit better hardness and wear performance than T-700 but worse than T-800. The HEA having an equal mixture ratio of T-800 and T-700, with the largest configurational entropy of 1.58R, performs the best in wear resistance among the HEAs. [ABSTRACT FROM AUTHOR]

The study of film-formation processes of oil paints has been extensively addressed over the last decade and the influence of metal ions in the drying and degradation stages of oil paints has been demonstrated. This research aimed to determine a suitable methodology for monitoring the early drying stages of selected commercial oil paint films and to gain an insight into the migration mechanisms of material degradation taking place between adjacent paint films, with special attention to the influence of the lead white. For this purpose, a hybrid approach was adopted to characterize the composition of the paint and highlight failure mechanisms in the paint films through a wide range of time. The methods included scribe tests, percentage weight variation (ΔW%), attenuated reflectance Fourier transform infrared spectrophotometry (ATR-FTIR), gas chromatography-mass spectrometry (GC-MS), and thermal analysis with differential scanning calorimetry (TG-DSC). The results show how metal ions interact with the oil binder and the pigment in the adjacent paint film: the transverse migration of lead white is shown to affect the reactivity of polyunsaturated triglycerides, increasing the rate of oxygen uptake and promoting the formation of radicals and bonds between polymer chains, depending on the pigment with which it interacts. [ABSTRACT FROM AUTHOR]

Phase equilibria were investigated between 200 and 800 °C in the Cu-Zn binary system. Wavelength dispersive spectroscopy (WDS) was performed to determine the equilibrium compositions, and differential scanning calorimetry (DSC) was performed to investigate the solidus and liquidus temperatures and the invariant reaction temperatures of the Zn-rich portion. The β/(α + β) boundary in the Cu-rich portion extended toward the Cu-rich side as the temperature decreased below the A2–B2 order–disorder transformation temperature, and the phase boundaries of the γ, δ and ε phases shifted toward the Cu-rich side. The liquidus temperatures of the ε + liquid were higher than those of the previous report. From the experimental results, the phase diagram of the Cu-Zn binary system was determined in the whole composition range. [ABSTRACT FROM AUTHOR]

The Mg-Sm phase diagram has been experimentally studied by x-ray diffraction, scanning electron microscope equipped with energy dispersive spectrometer, and differential scanning calorimetry. Five binary compounds, Mg41Sm5, Mg5Sm, Mg3Sm, Mg2Sm and MgSm were confirmed to exist in the Mg-Sm system. In addition to Mg2Sm and MgSm, Mg3Sm was found to be a congruently melting phase. The Mg5Sm and Mg2Sm were found to be only stable at high temperatures and decompose above 400 °C in this work. A special effort was made to determine the extent of the solid solubility ranges of Mg3Sm, Mg2Sm, MgSm and, γ-Sm. The Mg-Sm binary system was modeled using the Calphad approach based on new experimental data of this work and all reliable experimental information from literature. A complete thermodynamic description of the Mg-Sm system is obtained and extensive comparisons between calculated and experimental data are presented, indicating that almost all available experimental and theoretical data are fitted satisfactorily. [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]

Over the past three decades, bioresorbable ceramics such as beta-tricalcium phosphate (β-TCP)-based porous scaffolds have been extensively studied. β-TCP-based scaffolds or cements for bone tissue applications have proved to be an outstanding alternative to repair and regenerate bone tissue defects caused by trauma or injury. In this study, an investigation on submicron β-TCP powders derived from prawn shell (Fenneropenaeus indicus, a source of marine biowaste) via solid-state reaction approach was carried out, which has calcite (CaCO3) in its exoskeleton (nonedible). The prawn shell-derived β-TCP can be prepared conventionally with dicalcium phosphate (CaHPO4) at different temperatures 900, 1000, 1100, and 1200 °C. The EDX spectra detect the Ca:P ratio of 1.5 confirming the formation of pure β-TCP at 1100 °C, which is in complete agreement with theoretical ratio. X-ray diffraction pattern revealed the phase-pure crystalline rhombohedral crystal structure of β-TCP with an average crystallite size of ~ 25.8 nm, prepared at 1100 °C. The field emission scanning electron microscopy images showed a homogeneous distribution of β-TCP powders with an average grain size of 3.07 µm at 1100 °C. Furthermore, Raman spectroscopy and Fourier transform infrared spectroscopy confirm the characteristics peaks of β-TCP. Differential scanning calorimetry and thermogravimetric analysis are performed to study the thermal behavior of the initial precursors mixture to synthesize β-TCP. β-TCP scaffolds sintered at 1100 °C exhibited compressive strength of ~ 6.2 MPa, for which Ca/P ratio is 1.51. Biodegradation study conducted on β-TCP scaffolds sintered at 1100 °C has shown slow degradation rate up to 5 days. Therefore, the prawn shell-derived β-TCP has physical and morphological properties which projects it as a promising implantable biomaterial for synthetic bone graft substitutes. [ABSTRACT FROM AUTHOR]

Large-scale synthesis of hexagonal boron nitride (hBN) by a liquid exfoliation technique has been demonstrated in the present study. It is a low-cost and efficient method for exfoliating 2D materials like hBN. Here, a two-step approach was acquired to exfoliate the bulk hBN. In the first step, the bulk hBN was dispersed using a probe sonicator in a solution of gelatin, potassium chloride (KCl) and zinc chloride (ZnCl2), and in the second step, further exfoliation was achieved by centrifugation process. Exfoliation was achieved by both centrifugation and intercalation of Zn2+ and K+ ions within the layers of hBN. The supernatant obtained after centrifugation was heated to 600 °C for a duration of 1 h in an air atmosphere to eliminate the gelatin which was again heat treated for the same duration at 800 °C in an Ar atmosphere to improve its crystallinity. The hBN nanoplatelets obtained from the bulk hBN were characterized using various analytical techniques such as x-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), differential scanning calorimetry and thermogravimetric analysis (DSC/TGA) and atomic force microscopy (AFM) to determine their properties. The hBN nanoplatelets showed a thickness range of ~ 50-270 nm and a lateral dimension range of ~ 1-3 μm. FTIR analysis confirmed the presence of hydroxyl (OH) functional group attached to the hBN nanoplatelets due to the absorption of surface moisture. The hBN nanoplatelets showed excellent thermal stability up to a temperature of ~ 726.16 °C. The liquid exfoliation approach used in the present work was found to be a highly effective method and shows potential for producing hBN nanoplatelets with a few layers. [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]

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]

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 lunar regolith can be utilized as raw materials for constructing lunar bases through the fabrication of lunar cement. However, the low CaO content in lunar regolith presents a challenge for producing silicate cement. This study explores enriching CaO in NEU-1 lunar soil simulant by calciothermic reduction. Non-isothermal differential scanning calorimetry analysis indicated that calcium reacted with Fe2O3, SiO2, and Al2O3 at approximately 808°C, 816°C, and 826°C, respectively. The reaction ratios were 1.1, 1.6, and 0.8, with apparent activation energies of 941.6 kJ/mol, 965.17 kJ/mol, and 547.28 kJ/mol. The products obtained from the calciothermic reduction of lunar soil simulant were CaO, Ca2Si, and AlFe, as analyzed by X-ray diffraction. Increasing the temperature was found to be beneficial to the reaction process, and a suitable reaction temperature of 850°C was determined. X-ray photoelectron spectroscopy analysis showed that the reduction percentages of SiO2 and Al2O3 were 93.01% and 91.04%, respectively, at 850°C for 30 min. The CaO content in the product obtained by calciothermic reduction was 50.65%, which could be further increased to 81.16% after crude purification, and the CaO yield was 82.57%. These results demonstrated that the process has a significant CaO enrichment effect. [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]

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]

Differential scanning calorimetry (DSC) is used to determine the magnetic phase transformation temperatures of the La1 – xYxMn2Si2 (x = 0–1) alloys. For the compositions with х from 0 to 0.3, the temperature dependences of DSC signal exhibit λ-like endothermic effects observed near 300 K, which are related to the magnetic phase transition from the ferromagnetic to layered antiferromagnetic structure, and weak anomalies, which are observed in a temperature range of from 458 K for the composition with х = 0 to 323 К for the composition with х = 0.3 upon disordering of the layered antiferromagnetic structure. A clear endothermic peak corresponding to the disordering of interplane antiferromagnetic layered structure was found for the YMn2Si2. The data obtained are used to construct the magnetic phase diagram of the La1 – xYxMn2Si2 system in a temperature range of 270–600 К. The differential scanning calorimetry is shown can be successfully used for the determination of temperatures of various magnetic phase transformations in rare-earth intermetallic compounds. [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]

Differential scanning calorimetry (DSC) and confocal scanning laser microscopy (CSLM) were used to investigate the effects of different cooling rates on the solidification and segregation characteristics of Cu-Ni-Si alloy. The microstructures were characterized by electron probe microanalysis and scanning electron microscope. The effects of cooling rate on segregation degree, grain size, solidification temperature and secondary dendrite spacing (λ2) were analyzed, and the correlation function was established. The results show that the characteristic temperature of DSC phase transformation is similar to the characteristic temperature of CSLM in situ microstructure evolution. Increasing cooling rate can reduce segregation degree and refine grains. The relationships between cooling rate and crystallization temperature (TL→S) and secondary dendrite spacing (λ2) with cooling rate are as follows: TL→S = 176 × exp(− v/17.6) + 891 and λ2 = 63 × v−0.236, respectively. The above relations were applied to predict the solidification microstructure characteristics produced by twin-roll strip casting and ingot casting processes, and the predicted results are in good agreement with the experimental values. The advantages of grain refinement and segregation improvement and its optimization mechanism of twin-roll strip casting have been clarified. [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]

The paper focuses on the investigation of the effect of heat input on the microstructure and mechanical properties of welded joints produced by electron beam welding of 4.0 mm-thick AW2099 aluminum-lithium alloy. This type of alloy is intended for application in an airplane fuselage. Information on electron beam welding of such type of materials is up to now is very limited. Non-dendritic equi-axed zone (EQZ) was observed at the heat-affected zone–weld metal interface. The higher heat input (HHI) led to the development of EQZ with a larger width. The thickness of EQZ was non-uniform across the base material thickness. EQZ was characterized by the presence of higher amounts of elements at the grain boundaries due to segregation. Eutectics based on α-aluminum + θ-Al2Cu were detected in those areas. Transmission electron microscopy detected the presence of AlLi and Al2Li3 intermetallic phases in the weld metal. Dissolution of the low-temperature δ'-Al3Li phase was observed by differential scanning calorimetry (DSC). Higher peak temperatures of a thermal cycle were measured during HHI welding. A peak temperature of 451 °C at a distance of 1.5 mm from the weld centerline was measured. The dissolution of precipitate particles caused by a thermal welding cycle resulted in the drop of microhardness in the fusion zone. Mean microhardness was slightly higher in the case of lower heat input (LHI) welding, i.e., 73% of that of the base material. The maximum weld tensile strength reached more than 83.8% of that of base materials. The fracture surface revealed the presence of dimples and bright brittle surfaces along with the microcracks and grain boundary eutectics. [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]

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]