Search Results (93)

The pursuit of sustainable winter road maintenance has intensified the need for deicers that balance functional effectiveness, economic viability, and minimal environmental impact. However, the absence of a systematic, multi-dimensional evaluation framework has hindered informed product selection and green procurement. This study develops and validates the Comprehensive Deicer Multi-criteria Evaluation System (CDMES)—a structured assessment framework that integrates economic, functional, environmental, and infrastructural sustainability dimensions. The evaluation index system was constructed for deicers, consisting of 18 indicators including preparation cost, engineering maintenance cost, operability of agent preparation, application difficulty, asphalt binder adhesion loss, minimum application concentration, proportion of active ingredients, effective time, ambient temperature, freezing point, solid dissolution rate, relative snow/ice-melting capacity, seed damage rate, chlorophyll attenuation, soil pH, aqueous solution pH, steel–carbon corrosion rate, and pavement friction attenuation rate. Subsequently, the analytic hierarchy process (AHP) was employed to determine the weight of each indicator, and evaluation criteria were established in accordance with relevant standards and literature. Finally, this weight determination method, combined with the simple additive weighting (SAW) method for index aggregation, forms a quantitative evaluation model. These elements together constitute a comprehensive deicer evaluation system, designated as the Comprehensive Deicer Multi-criteria Evaluation System (CDMES). Validation using three representative deicers—sodium chloride, a composite chloride-based formulation, and an organic acetate-based product—demonstrated that the CDMES can effectively discriminate product performance across multiple sustainability dimensions and identify critical weaknesses that may be obscured by purely compensatory scoring. The framework offers a transparent and reproducible decision-support tool for winter maintenance managers seeking to align deicer selection with sustainability objectives. Full article

Ionic liquids (ILs) derived from bioactive compounds have emerged as a versatile and highly tunable platform for designing novel functional materials with biomedical applications. Many of these systems incorporate naturally occurring carboxylate anions of relevance to medicinal chemistry, biotechnology, and biomedicine, which has intensified interest in this family of bioinspired ILs. This review focuses on ILs derived from carboxylic acids of natural origin, including fatty acids, phenolic acids, and hydroxy acids, and highlights recent advances in their design, bioactivity, and physicochemical characterization, with particular emphasis on systems based on biocompatible components. Additionally, it addresses synthetic strategies, toxicological aspects, and biological potential. Key physicochemical properties discussed include thermal stability, glass transition temperatures, melting and crystallization points, viscosity, density, solubility, refractive index, polarity, and amphiphilic behavior. Full article

To investigate the deterioration law of the mechanical properties of PVA-fiber-reinforced rubber concrete under the combined action of high-temperature and salt erosion, physical index tests, dynamic mechanical property experiments, and microstructural morphology observations were carried out on specimens subjected to different temperatures (ambient temperature, 100 °C, 300 °C) and various solution attacks (water, 5% NaCl, 5% Na₂SO₄, and 5% NaCl + 5% Na₂SO₄ mixture). The results show that, after exposure to 300 °C, the PVA fibers melt and the rubber pyrolyzes, since this temperature exceeds their melting points. A residual pore network is formed inside the matrix, and the damage degree of ultrasonic pulse velocity is about 2.3 times that of the 100 °C group. Although salt solution and its crystallization products can physically fill the pores and cause a partial recovery of pulse velocity, this change is mainly due to the alteration of the pore medium and does not represent a substantial restoration of the microstructure. The effects of different salt solutions on dynamic mechanical properties vary significantly: Sulfate erosion improves the dynamic performance significantly at ambient temperature by forming gypsum and ettringite to fill pores, but this strengthening effect disappears after 300 °C. Sodium chloride attack generates Friedel’s salt and consumes C₃A, leading to general strength deterioration. In composite salt erosion, the competitive and synergistic effects of Cl⁻ and SO₄²⁻ destabilize erosion products and weaken interfacial bonding, resulting in consistent decreases in dynamic compressive strength and elastic modulus under all temperatures and impact pressures. The strength reduction reaches 66.2% after 300 °C. Microscopic analysis confirms that composite salt erosion leads to the dissolution of ettringite and loose structure, which verifies the synergistic deterioration law of macroscopic properties. This study systematically reveals the damage evolution mechanism of PVA-fiber-reinforced rubber concrete under the coupled action of high-temperature and salt erosion, and provides a theoretical basis for the dynamic bearing capacity evaluation and durability design of concrete structures in such coupled environments. Full article

Rheological data of wood plastic composites (WPCs) are not readily present in many of the common scientific databases. For this reason, designing the processing of WPCs, e.g., extrusion, is difficult or even impossible, and it is often necessary to conduct research on your own to obtain the proper data. In the first part of the paper, studies of WPCs’ rheology have been performed in laboratory and production conditions. Tests in laboratory conditions have been conducted based on High-Pressure Capillary Rheometry (HPCR), using the Melt Flow Index (MFI). Tests in production conditions (on-line) have been performed by measuring the extrusion die pressure and extrusion throughput. The MFI’s viscosity and on-line viscosity results have been assessed against those of HPCR. In the second part of the paper, the viscosity data and models have been used for extrusion process simulations. Experimental studies of the process have been performed, and the experimental results have been used for evaluating the models applied. It was found that the two-point MFI method of determining viscosity and the on-line tests may be a reasonable alternative in the absence of HPCR data. The MFI method using the power-law model is fast and easy to apply and allows for analytical solutions to many processing problems. A significant advantage of on-line tests is that they are performed under real flow conditions of the tested material rather than laboratory conditions that do not take into account the material processing history. Full article

Topological graph theory provides a quantitative approach to understanding the structural complexities of sulfonamide compounds, which are prominent for their therapeutic importance in cancer treatment. A new computational scheme to predict the physicochemical and biological functions of sulfonamide derivatives, based on connection numbers and connection-based topological indices as alternatives to the theoretically overt degree-based index, is proposed. A set of structurally diverse sulfonamide compounds as chemical graphs is considered, and the relevant graph descriptors are computed using different connection numbers. Due to the complexity of the calculations involved in connectivity and other such indices, algorithms were developed in Python 3.12.12 to automate the extraction and calculation of these indices. QSPR analysis, with the help of supervised machine learning models like linear regression, among others, and various statistical techniques, was employed to obtain insight into the relationships existing between the structural properties and the molecular properties measured, such as melting point, molecular weight, etc. These results demonstrate the great predictive capability of connection-based indices in assessing pharmacologic efficacy or molecular behavior. The holistic setting thus links topological modeling to data-driven prediction and provides a window into the rational design and optimization of sulfonamide-based cancer therapeutics. Full article

Mn⁴⁺-doped fluoride red phosphors are widely used in white LED lighting and display applications due to their excellent luminescent properties. However, their synthesis relies heavily on highly toxic aqueous hydrofluoric acid, which not only causes severe environmental and soil/water pollution but also makes it difficult to control the microstructure of the products due to the rapid reaction rate. In this study, low-melting-point NH₄HF₂ was used as the molten salt, with KMnO₄ and MnF₂ as manganese sources, to synthesize the red phosphor K₃AlF₆: Mn⁴⁺ via the molten salt method. After the reaction, impurities such as NH₄HF₂ were removed by washing with a dilute H₂O₂ solution. The microstructure, photoluminescence properties, thermal quenching behavior, and application in warm white light-emitting diodes (W-LEDs) of the K₃AlF₆: Mn⁴⁺ phosphors were investigated. The results indicate that the phosphors prepared by this method consist of a single pure phase. By adjusting the molten salt content, the morphology of the product can be transformed from nanoparticle-like to nanorod-like structures. All products exhibit the characteristic red emission of Mn⁴⁺ under blue and violet light excitation, with the optimally doped sample achieving an internal quantum efficiency (IQE) of 69% under blue light excitation. The combination of the obtained K₃AlF₆: Mn⁴⁺ with the yellow phosphor YAG enabled the fabrication of W-LEDs. These W-LEDs achieved a color rendering index (Ra) of 86.8, a luminous efficacy (LE) of 77 lm/W, and a correlated color temperature (CCT) of 3690 K, along with excellent color stability under operating conditions. Full article

In this paper, we study the detour eccentric sum index (DESI) to obtain the Quantitative Structure–Property Relationship (QSPR) for different molecular structures. We establish theoretical bounds for this index and compute its values across fundamental graph families. Through correlation analyses between the physicochemical properties of molecular structures representing anti-malarial and breast cancer drugs, we show the high predictive value of two topological parameters, detour diameter (DD) and detour radius (DR). Specifically, DR shows strong positive correlations with boiling point, enthalpy, and flash point (up to 0.94), while DD is highly correlated with properties such as molar volume, molar refraction, and polarizability (up to 0.97). The DESI was then selected for detailed curvilinear regression modeling and comparison against the established eccentric distance sum index. For anti-malarial drugs, the second-order model yields the best fit. The DESI provides optimal prediction for boiling point, enthalpy, and flash point. In breast cancer drugs, the second-order model is again favored for properties except for melting point, best described by a third-order model. The results highlight how well the index captures subtle structural characteristics. Full article

Polyethylene (PE) melt-blown nonwoven materials exhibit excellent infrared transmission properties, making them well-suited for applications in infrared physiotherapy and smart building technologies. However, their high flammability and tendency to generate melting droplets and smoke seriously limit their applications. Herein, phosphorus-silicon flame-retardant PE melt-blown blends were prepared by the melt blending of ammonium polyphosphate (APP) and nano-silica (SiO₂). Next, the thermal, rheological, and crystallization properties of the blends were investigated. Subsequently, flame-retardant PE melt-blown nonwoven materials were prepared and tested. It was found that APP and SiO₂ decreased the melt flowability of the material, while slightly decreasing the melting point, increasing crystallinity and enhancing the thermal stability by shifting the decomposition temperature by 51 °C. Moreover, the presence of flame retardants increased the roughness and diameter of fibers. The limiting oxygen index (LOI) of the PE melt-blown materials with 10% APP and 1% SiO₂ reached 28.6%, reaching the flame-retardant level without dripping during combustion. This highlights important guidelines for developing infrared-transmitting, flame-retardant PE nonwovens for safe and sustainable applications. Full article

Common polymeric materials (neat polymers) are quite well known, and their properties are often available in appropriate material databases. However, material data, e.g., rheological data, for materials such as polymer blends, polymer composites (including wood plastic composites), and filled plastics are simply lacking in material databases. This paper addresses the problem of determining viscosity curves for one of the most widely used advanced polymeric materials: wood plastic composites. Studies were conducted in laboratory and production settings, i.e., on-line. Laboratory tests were conducted in two ways: on the basis of classical rheometric measurements, i.e., High-Pressure Capillary Rheometry (HPCR), and on the basis of Melt Flow Index (MFI) measurements, also including tests based on a limited number of measurement points. Tests in production conditions, i.e., on-line, were conducted during the extrusion process using the measurement of the process output (material flow rate) and pressure in a specialized extrusion die. The test results (viscosity curves) obtained from Melt Flow Index (MFI) measurements and on-line measurements were presented and evaluated against the background of the results (viscosity curves) obtained from classical capillary rheometry measurements (HPCR). Due to the lack of rheological data of wood plastic composites in available databases, in-house research methods based on the two-point viscosity curve determination in the plastometric (MFI) tests and the tests under production conditions, that is, on-line, have been proposed. The two-point method, based on the power law model, is quick and easy to implement, and allows for solving many polymer processing issues analytically. On-line tests have the significant advantage of being conducted under the actual flow conditions of the tested material, rather than under laboratory conditions, as is the case with rheometric and plastometric tests, which do not take into account the processing history of the tested material. The issues of rheology and modeling of wood plastic composite processing, e.g., extrusion and injection molding, which have not yet been resolved and require practical solutions, were also discussed. The results of this part of the study (viscosity curves and models) will be used in the second part of the study to evaluate the impact of rheological testing methods and rheological models on the accuracy of process modeling (extrusion). Full article

The current study examines the feasibility of Ultrasint PP nat 01 polypropylene material in powder bed fusion through powder characterisation. The results obtained are also deemed to be pertinent when developing or validating analytical and numerical models of Polymer Laser Sintering, which were not within the scope of this paper. The following critical characteristics were examined: powder morphology, powder particle size distribution (PSD), bulk density, tapped density, melt flow index, thermal characteristics of the material, degree of crystallinity, and optical properties. Ultrasint PP nat 01 powder has a PSD in the range of 20–80 µm, which is within the recommended particle size distribution. The Hausner ratio, tapped density, and bulk density of the material were calculated and measured as 1.230 ± 0.05, 0.455 ± 0.02 g/cm³, and 0.370 ± 0.03 g/cm³, respectively. The melt flow index of Ultrasint PP nat 01 was measured as 15.8 g/10 min. The initial melting point of the material was determined to be 133.8 °C. The powder used had a relatively high sintering window of 30.7 °C, a degree of crystallinity of around 31.8%, and a high thermal stability of around 461.52 °C. The material was found to attain full fusion of particles at around 170 °C. Fourier Transform Infrared Spectroscopy indicated that Ultrasint PP nat 01 powder has poor radiation absorption, but high transmission properties. Full article

The recycling of polypropylene (PP) packaging films modified with biobased additives: biochar derived from the pyrolysis of natural fibers and diatomaceous earth was investigated. The aim was to assess the impact of these modifiers on the processing, rheological, mechanical, and thermal properties of the recycled material. The processing behavior was evaluated through extrusion with granulation to determine industrial applicability. Rheological properties, including viscosity and melt flow index (MFI), were measured to characterize flow behavior. Mechanical performance was assessed through tensile strength, hardness, three-point bending, and impact resistance tests. Thermal properties were analyzed using thermogravimetric analysis (TGA), Vicat softening temperature (VST), and differential scanning calorimetry (DSC). The results demonstrate that incorporating biochar and diatomaceous earth can modify and, in selected cases, enhance the processing and performance characteristics of recycled PP films, though their impact on thermal behavior is parameter-specific. While diatomaceous earth slightly increased the onset of thermal degradation (T₅), both fillers caused a slight decrease in the VST, indicating reduced heat resistance under load. Diatomaceous earth was found to effectively improve stiffness and impact strength, while biochar reduced viscosity and promoted finer crystalline structures. Both additives acted as nucleating agents, increasing crystallization temperatures, with diatomaceous earth additionally delaying thermal degradation onset. These findings highlight the potential of using sustainable, waste-derived additives in polymer recycling, supporting the development of environmentally responsible materials within circular economy frameworks. Full article

Objectives: Although 3D-printing has been identified as a promising technique for personalised medicine manufacturing, developing complex formulations that are suitable for the process can be challenging. This study evaluates the use of a mixture design for the targeted development of an optimised formulation designed for the 3D-printing of oral dosage forms containing the drug sertraline hydrochloride featuring immediate-release drug dissolution. Methods: The polymers Eudragit E PO, Kollidon 17 PF and hydroxypropyl cellulose were compared in simple screening experiments regarding their extrudability, printability and disintegration. A combination of Eudragit E PO and Kollidon 17 PF proved superior and therefore served as the basis for the mixture design. The resulting blends were processed via hot melt extrusion to produce filaments, which were then measured for bending stress using a 3-point-bending-test, and 3D-printed sample plates were used to determine the crystallinity index of sertraline hydrochloride using X-ray diffraction in a previously identified range with low interference from the other components. The formulation was optimised using statistically based models with the aim of minimising the bending stress to obtain flexible, process-robust filaments and simultaneously minimising the crystallinity index with the intention of improving the solubility of the drug by maximising its amorphous content. Results: The filaments made from the optimised formulation could be reliably printed, and the amorphous state of the active ingredient therein was confirmed. The oral dosage forms produced from these showed immediate release characteristics in an acidic medium. Conclusions: This study demonstrates the advantages of a mixture design for optimising complex formulations in a time- and resource-efficient way and could serve as a basis for other research groups to develop innovative, customisable drug delivery systems more effectively. Full article

This study systematically investigates the impact of hydrolytic degradation on the crystallization kinetics and morphology of poly(butylene succinate-co-adipate) (PBSA). Gel Permeation Chromatography (GPC) confirmed extensive chain scission, significantly reducing the polymer’s weight-average molecular weight (M_w from ~103,000 to ~16,000 g/mol) and broadening its polydispersity index (PDI from ~2 to 7 after 64 days). Differential scanning calorimetry (DSC) analysis revealed that hydrolytic degradation dramatically accelerated crystallization rates, reducing crystallization time roughly 10-fold (e.g., from ~3000 s to ~300 s), and crystallinity increased from 34% to 63%. Multiple melting peaks suggested the presence of lamellae with varying thicknesses, consistent with the Gibbs–Thomson equation. Isothermal crystallization kinetics were evaluated using the Avrami equation (with n ≈ 3), reciprocal half-time of crystallization, and a novel inflection point slope method, all confirming accelerated crystallization; for instance, the slope increased from 0.00517 to 0.05203. Polarized optical microscopy (POM) revealed evolving spherulite morphologies, including hexagonal and flower-like dendritic spherulites with diamond-shape ends, while wide-angle X-ray diffraction (WAXD) showed a crystallization range shift to higher temperatures (e.g., from 72–61 °C to 82–71 °C) and a 14% increase in crystallite diameter, aligning with increased melting point and lamellar thickness and overall increased crystallinity. Full article

Optical microfiber biosensors demonstrate exceptionally ultra-high sensitivity at the dispersion turning point (DTP). However, the DTP is highly susceptible to variations in dimensional and external environmental factors, and the spectral response is mismatched from preparation in air to application in a liquid environment, making the DTP difficult to control effectively. In this work, we propose a method that bridges the relationship between the interference spectra of air and aqueous environments. By counting the interference peaks in air, we can accurately predict the DTP position in liquids. Meanwhile, it provides a new balance between sensitivity and wide linear dynamic range, achieving wide dynamic range detection across various concentrations. The optical microfiber coupler (OMC) is fabricated using the hydrogen–oxygen flame melting tapering method. In addition, the concentration, temperature, and solvent used for the sensor’s biofunctional layer are optimized. Finally, in refractive index sensing, a maximum sensitivity of 1.17 × 105 ± 0.038 × 105 nm/RIU is achieved. For biosensing, a wide dynamic range detection of cardiac troponin I (cTnI) is realized at concentrations of 12–48 ng/mL, 120–480 pg/mL, and 120–480 fg/mL. Full article

High-melting point 1,3-diacylglycerols not only provide health benefits, but are also suitable for manufacture of foods containing various specialty fats. It is difficult to prepare such high-melting point diacylglycerols, as the activities of specific enzymes will severely reduce at their melting points. In the present study, a combined technique was developed to prepare 1,3-dipalmitoylglycerol (1,3-DPG) and 1,3-distearoylglycerol (1,3-DSG) using selective esterification, molecular distillation, and solvent fractionation. Lipozyme TL IM was suitable for use as the optimal enzyme to maintain relatively high activity levels at esterification temperatures of 73–75 °C. 1,3-DAG/(DAG + TAG) was selected as the most important index to monitor the esterification and to evaluate the synthesized fats. The obtained 1,3-DPG and 1,3-DSG showed high purities, at more than 83%, and possessed hard attributes at room temperature. Both 1,3-DPG and 1,3-DSG exhibited fat crystals with β′ and β crystals. Needle-like and rod-like crystals were observed at 5–25 °C for 1,3-DPG, and closely packed feather-like crystals were found at 5–20 °C for 1,3-DSG, indicating their multiple abilities in modifying the crystallization stabilization of the fat matrix during food processing. Full article