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Glass is one of the oldest and most versatile manmade materials and has been used for centuries. One of the areas of significant research and progress is that of high-mechanical-resistance glass. Several processes can be used to maximize the mechanical strength of glasses, namely thermal or chemical treatments. Glass ceramics, obtained through controlled crystallization, can enhance the mechanical properties of these materials and, as long as the crystals remain small enough, transparent glass ceramics can be obtained. On the other hand, ion exchange can strengthen the glass surface and reduce failure. As a result, ceramization followed by ion exchange can further enhance the mechanical characteristics of the parent glass. Aluminosilicate glasses and glass ceramics are known to present excellent transparency and chemical durability, plus good mechanical behavior; therefore, a lithium aluminosilicate glass composition was studied in order to obtain transparent glass ceramics, followed by an ion exchange process, and its mechanical properties were studied. Transparent glass ceramics were obtained, with an increase of ~15% in hardness over the parent glass. The glass ceramics were then subjected to an ion exchange treatment in a KNO₃ bath, in order to further enhance the mechanical properties, without hindering the optical transmittance. The combination of heat treatment and chemical treatment resulted in a cumulative hardness increase of ~25%, from 620 ± 10 HV, for the as-cast glass and from 773 ± 23 HV for the ion-exchanged glass ceramic. Regarding the indentation fracture toughness, values obtained for the glass ceramics were similar to those obtained for the cast glass, yielding no noticeable change. Indentation fracture toughness increased after the ion exchange treatment of the glass ceramic, since a much higher load was necessary to obtain a measurable indentation, indicating higher indentation fracture strength. Full article

Monodisperse films of spherical tantalum oxide (V) nanoclusters and spherical tantalum nanoclusters with a tantalum oxide shell with diameters of 1.4–8 nm were obtained by magnetron sputtering. The size of the deposited nanoclusters was controlled using a quadrupole mass filter. The chemical composition was certified using the XPS method. Using the Reflected Electron Energy Loss Spectroscopy (REELS), the dependence of the band gap width on the nanocluster size was determined. It was found that starting from a certain nanocluster size, the band gap width increases as the nanocluster size decreases. Based on experimental data and a theoretical model, the effective mass of electrons dependence as a function of nanocluster size was obtained. Full article

Berthierine was found in a natrolite vein intersecting volcanogenic-sedimentary rocks on the slope of Mt. Quamdespakh in the upper reaches of the Suolwai River, Lovozero alkaline massif, Kola peninsula, Russian Arctic. The mineral occurs as well-formed translucent pyramidal crystals up to 250 μm in size. The chemical composition determined by electron microprobe analysis corresponds to the empirical formula ^VI(Fe²⁺_1.99Al_0.94Mg_0.03Mn_0.04)_Σ3.00[^IV(Si_1.15Al_0.85)_Σ2.00O₅] [(OH)_3.92O_0.08]_Σ4.00; the idealized formula is ^VI(Fe²⁺₂Al)[^IV(SiAl)O₅](OH)₄. The crystal-structure determination (the first detailed crystal-structure characterization of berthierine) shows that the Lovozero mineral is hexagonal, P6₃cm (a = 5.3903(4), c = 14.0146(10) Å, V = 352.64(6) ų, R₁ = 0.053 for 338 unique observed reflections), and corresponds to the 2H₁ polytype of serpentine-group minerals with 1:1 tetrahedral-octahedral layers. The unit cell contains two M₃[T₂O₅](OH)₄ layers (M = Fe²⁺,Al; T = Si,Al) stacked along the c axis. The calculations of information-based structural and topological complexity parameters indicate that berthierine is structurally and topologically simpler than its chlorite-group polymorph chamosite. Since berthierine usually crystallizes metastably in the stability field of chamosite, the complexity analysis is agreement with the Goldsmith rule that states that, in Ostwald sequences of crystallization, metastable phases are simpler and more disordered than their stable counterparts. This observation can be applied to a general case of the metastable formation of serpentine-group minerals prior to the crystallization of chlorites. Full article

The large-scale insect rearing sector is expected to grow significantly in the next few years, with Hermetia illucens L. (black soldier fly, BSF) playing a pivotal role. As with traditional livestock, it is essential to improve and ensure BSF welfare. A starting point can be an adaptation of the Five Freedoms framework. Feed availability must be optimized to meet larvae nutritional needs (freedom from hunger) while maximizing substrate conversion efficiency. Similarly, rearing density needs to be optimized to ensure well-being, particularly in large-scale operations. In this study, Control (commercial laying hen feed) and Omnivorous substrates (vegetable and meat) were used as dietary regimes. In the first trial, three feeding rates were tested: 50, 100, and 200 mg feed/larva/day; in the second trial, three rearing densities were evaluated: 5, 10, and 15 larvae/cm². Performance parameters, including final larval weight, final frass biomass, growth rate, substrate reduction, feed conversion ratio, larval length, survival rate, larvae chemical composition, and process optimization, were studied. Our results show that a feeding rate of approximately 90 mg feed/larva/day in the Omnivorous diet and 175 mg feed/larva/day in the Control diet, along with a rearing density of 5 and 7.57 larvae/cm², respectively, in the Omnivorous and Control diets, produced optimal growth performances ensuring larval well-being. This outcome offers valuable insights for implementing good welfare practices in the insect farming sector and optimizing rearing management and efficiency. Full article

One of the concepts behind Generation IV reactors is a molten salt coolant system, where the materials for the reactor itself and for the primary and secondary circuit components are subjected to extreme chemical and thermal stresses. Due to the unavailability of these materials, a nickel–molybdenum alloy known as MoNiCr has been developed in the Czech Republic. This paper discusses the manufacturing process for the MoNiCr alloy, covering conventional casting technology, forming, powder atomization, additive manufacturing (AM) using the directed energy deposition (DED-LB) process, and final heat treatment. Special attention was given to the quality of the input powders for additive manufacturing, particularly regarding the optimization of the chemical composition, which significantly influenced the quality of the additively manufactured components. AM enables the realization of complex structural designs that are critical for energy applications, despite the high susceptibility of the MoNiCr alloy to solidification cracking. Through AM, a test body was successfully produced with a maximum defect rate of 0.03% and the following mechanical properties: a yield strength (YS) of 279 MPa, an ultimate tensile strength (UTS) of 602 MPa, and an elongation (El) of 51%. Full article

This study addresses the critical challenge of carbon corrosion in proton exchange membrane fuel cells (PEMFCs) by developing hybrid supports that combine the high surface area of carbon black (CB) with the superior crystallinity and graphitic structure of carbon nanofibers (CNFs). Two commercially available CB samples were physically activated and composited with two types of CNFs synthesized via chemical vapor deposition using different carbon sources. The structure, morphology, and crystallinity of the resulting CNF–CB hybrid supports were characterized, and the performances of these hybrid supports in mitigating carbon corrosion and enhancing the PEMFC performance was evaluated through full-cell testing in collaboration with a membrane electrode assembly (MEA) manufacturer (VinaTech, Seoul, Republic, of Korea), adhering to industry-standard fabrication and evaluation procedures. Accelerated stress tests following the US Department of Energy protocols revealed that incorporating CNFs enhanced the durability of the CB-based hybrid supports without compromising their performance. The improved performance of the MEAs with the hybrid carbon support is attributed to the ability of the CNF to act as a structural backbone, facilitate water removal, and provide abundant edge plane sites for anchoring the platinum catalyst, which promoted the oxygen reduction reaction and improved catalyst utilization. The findings of this study highlight the potential of CNF-reinforced CB supports for enhancing the durability and performance of PEMFCs. Full article

The dissolution of dolomite can not only provide the chemical components in hot springs but also provide a high-quality reservoir for geothermal resources. However, there is still debate about the main controlling factors and mechanisms of the dissolution process of dolomite. The Shuijing hot springs in Guizhou Province are rich in SO₄²⁻ and the geothermal reservoir is dolomite, which provides an excellent opportunity to understand the role of SO₄²⁻ in the dissolution process of dolomite. In this paper, water–rock interaction experiments were conducted at different temperatures to study the effects of SO₄²⁻, pH, and CO₂ on the dissolution of dolomite from the Shuijing hot springs geothermal reservoir. The results indicate that temperature is a significant factor affecting the chemical composition of hot springs water, with higher temperatures having a more pronounced effect on the dissolution of dolomite. At lower temperatures of 25 °C and 90 °C, the molar ratio of the released Ca²⁺ and Mg²⁺ during the dissolution of dolomite in the initial reaction stage generally approaches the Ca/Mg molar ratio of dolomite, exhibiting congruent dissolution. However, at elevated temperatures of 150 °C, the released Ca/Mg molar ratio surpasses the Ca/Mg molar ratio of dolomite, demonstrating an incongruent dissolution characteristic with Ca²⁺ being preferentially released over Mg²⁺. Additionally, the relative importance of CO₂, SO₄²⁻ and pH on the dissolution degree of dolomite is CO₂ > SO₄²⁻ > pH = 4 > pH = 7 > pH = 10. The promotion effect of SO₄²⁻ on dolomite dissolution indicates that the greater the SO₄²⁻ concentration, the stronger the dissolution of dolomite, and its dissolution ability is enhanced with the increase in temperature. Furthermore, the effect of CO₂ on the dissolution of dolomite is stronger than that of SO₄²⁻, leading to the oscillating fluctuation trend of the released Ca²⁺ and Mg²⁺. Full article

This review presents a comprehensive review of cellulose–chitosan-based biocomposites that have high potential as sustainable alternatives to synthetic polymers. These biocomposites, due to biocompatibility, biodegradability, and antimicrobial properties, attract attention for wide application in various industries. This review includes modern methods for producing cellulose–chitosan composites aimed at improving their mechanical and chemical properties, such as strength, flexibility, and water resistance. Particular attention is paid to the use of composites in packaging materials, where they provide protection and durability of products, and help reduce the environmental footprint. In medicine, such composites are used for drug delivery and tissue engineering, providing controlled release of active substances and tissue regeneration. In addition, their advantages in wastewater treatment are discussed, where the composites effectively remove heavy metal ions and organic pollutants due to their high sorption capacity. This study focuses on the wide potential of cellulose–chitosan biocomposites and their role in solving environmental problems. Full article

Citrus fruit peels are a rich source of essential oils (EOs), which contain biologically active compounds; however, they are often discarded as waste, which causes pollution. The fresh peels of eight citrus cultivars growing in Pakistan were used to extract EOs through steam distillation. Gas chromatography-mass spectrometry (GC-MS) analysis of fresh peel EOs revealed that limonene was the most abundant compound, constituting 94.5%, 96.1%, 95.3%, 93.3%, 56.2%, 91.5%, 96.4%, and 96.7% of Citrus jambhiri, C. aurantium, C. sinensis var. Malta cv. Blood Malta, C. sinensis var. Malta cv. Shakri Malta, C. limon, C. pseudolimon, C. reticulata var. Mandarin cv. Feutrell’s Early, and C. reticulata var. Mandarin cv. Kinnow, respectively. The dried peel EO of C. reticulata var. Mandarin cv. Kinnow contained 95.2% limonene. C. limon peel EO exhibited the highest antibacterial activity among all citrus peel EOs with the minimum inhibitory concentration of 312 μg/mL against Staphylococcus aureus. The C. aurantium and C. sinensis var. Malta cv. Shakri Malta peel EOs exhibited the highest mosquito repellent activity against Ae. aegypti females, providing protection for 45 min when tested at a concentration of 166 µg/cm². This study showed C. aurantium and Shaki Malta peel EOs could be used to formulate natural mosquito repellent. Full article

White cast irons (WCI) are widely used in industries requiring high wear resistance due to their microstructure consisting of hard carbides dispersed within a metallic matrix. This study focuses on developing wear-resistant multi-component hypereutectic high chromium cast irons, merging concepts of high entropy alloys with the conventional metallurgy of white cast irons, specifically exploring the influence of carbide-forming elements such as V, Mo, and Ni on solidification behavior, microstructure, and wear performance. The research investigates the solidification process of the alloys using Computer-Aided Cooling Curve Analysis (CA-CCA) and characterizes the microstructures through X-ray diffraction (XRD) and scanning electron microscopy (SEM). The wear behavior of the developed alloys is evaluated through reciprocating sliding wear tests, revealing the impact of varying chemical compositions on wear resistance. The results demonstrate that high-entropy white cast iron (HEWCI), particularly those enriched with carbide-forming elements, exhibit superior abrasion resistance compared to conventional high-chromium cast irons. The alloy with 2 Mo and 4 V content showed the best performance, presenting the lowest wear rate (61.5% lower than HCCI alloy) and CoF (values ranging from 0.20 to 0.22) due to the highest concentration of V carbides. Full article

This study introduces a novel water-insoluble dispersant for coal water slurry (CWS), namely, a poly(sodium styrene sulfonate)-grafted SiO₂ nanoparticle (SiO₂-g-PSSNa). SiO₂-g-PSSNa was synthesized by combining the surface acylation reaction with surface-initiated atom transfer radical polymerization (SI-ATRP). Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectroscopy (XPS), energy dispersive spectrometer (EDS), nuclear magnetic resonance spectroscopy (NMR) and thermogravimetric analysis (TGA) verified that SiO₂-g-PSSNa with the desired structure was successfully obtained. Afterwards, the performance of SiO₂-g-PSSNa as a dispersant in CWS preparation was evaluated. The results indicated that the optimal dosage of SiO₂-g-PSSNa was 0.3%. Compared to the famous commercial products, PSSNa and lignosulfonate (LS), SiO₂-g-PSSNa exhibits improved viscosity reduction performance. When SiO₂-g-PSSNa was used as the dispersant, the maximum coal loading of CWS was 64.2%, which was higher than LS (63.4%) and PSSNa (63.9%). All CWSs obtained in this study were pseudoplastic fluids and more consistent with the Herschel–Bulkley rheological model. The turbiscan stability index (TSI) of CWS prepared with SiO₂-g-PSSNa was 0.05, which was significantly lower than CWSs obtained from PSSNa (0.30) and LS (0.36). Therefore, SiO₂-g-PSSNa also exhibits excellent stability performance. This result was confirmed by rod penetration tests. The underlying mechanism was also clarified by various measurements, such as contact angle, zeta potential, EDS and low-field nuclear magnetic resonance spectra (low-field NMR). The results reveal that SiO₂-g-PSSNa can adsorbed onto the coal surface. SiO₂-g-PSSNa possesses a special branched structure, which bears a higher charge density as compared to linear ones with approximate chemical composition. As a result, coal particles adsorbed with SiO₂-g-PSSNa exhibit more electronegativity. With the enhancement of the electrostatic repulsive between coal particles, the apparent viscosity was lowered and the static stability was improved. This study demonstrated that solubility in water is not an essential factor in engineering the dispersant. Densely charged groups are probably more important. Full article

The aim of the present study was to optimize the process parameters for the extraction and purification of total flavonoids from Polygonum perfoliatum L., in addition to analyzing their chemical composition and evaluating their activity against varicella-zoster virus (VZV) and antioxidant activity. The optimum extraction process was determined using one-way and response surface methods with the following conditions: ethanol concentration of 82.00%, temperature of 90.29 °C, solid-to-liquid ratio of 1:32.78 g/mL, extraction time of 1.5 h, and two extractions with a yield of 14.98 ± 0.11 mg/g. Purification was then carried out using D101 macroporous resin to obtain a flavonoid purity of 43.00 ± 2.55%, which was 3.38 times higher than that of the crude extract (12.74 ± 1.04%). Further purification was carried out using a 1:9 hybrid column of macroporous resin and polyamide, and the purity of flavonoids was enhanced to 59.02 ± 2.23%, which is 1.37 times higher than that of the macroporous resin purifier (43.00 ± 2.55%) and 4.63 times higher than that of the crude extract (12.74 ± 1.04%). Seventy-nine flavonoids were identified using ultra-performance liquid chromatography-tandem high-resolution mass spectrometry (UPLC-HRMS). In addition, the purified flavonoids showed good anti-VZV and antioxidant activities. Therefore, this study can provide technical support and theoretical basis for the further development and utilization of Polygonum perfoliatum L. resources. Full article

W-Mo-V high-speed steel (HSS) is a high-alloy high-carbon steel with a high content of carbon, tungsten, chromium, molybdenum, and vanadium components. This type of high-speed steel has excellent red hardness, wear resistance, and corrosion resistance. In this study, the alloying element ratios were adjusted based on commercial HSS powders. The resulting chemical composition (wt.%) is C 1.9%, W 5.5%, Mo 5.0%, V 5.5%, Cr 4.5%, Si 0.7%, Mn 0.55%, Nb 0.5%, B 0.2%, N 0.06%, and the rest is Fe. This design is distinguished by the inclusion of a high content of molybdenum, vanadium, and trace boron in high-speed steel. When compared to traditional tungsten-based high-speed steel rolls, the addition of these three types of elements effectively improves the wear resistance and red hardness of high-speed steel, thereby increasing the service life of high-speed steel mill-roll covers. JMatPro (version 7.0) simulation software was used to create the composition of W-Mo-V HSS. The phase composition diagrams at various temperatures were examined, as well as the contents of distinct phases within the organization at various temperatures. The influence of austenite content on the martensitic transformation temperature at different temperatures was estimated. The heat treatment parameters for W-Mo-V HSS were optimized. By studying the phase equilibrium of W-Mo-V high-speed steel at different temperatures and drawing CCT diagrams, the starting temperature for the transformation of pearlite to austenite (A_c1 = 796.91 °C) and the ending temperature for the complete dissolution of secondary carbides into austenite (A_ccm = 819.49 °C) during heating was determined. The changes in carbide content and grain size of W-Mo-V high-speed steel at different tempering temperatures were calculated using JMatPro software. Combined with analysis of A_c1 and A_ccm temperature points, it was found that the optimal annealing temperatures were 817–827 °C, quenching temperatures were 1150–1160 °C, and tempering temperatures were 550–610 °C. The scanning electron microscopy (SEM) examination of the samples obtained with the aforementioned heat treatment parameters revealed that the martensitic substrate and vanadium carbide grains were finely and evenly scattered, consistent with the simulation results. This suggests that the simulation is a useful reference for guiding actual production. Full article

Citrus peel essential oils (CPEOs) have demonstrated substantial medicinal potential for glioblastoma treatment because of their extensive antitumor effects, low potential for drug resistance, and ability to cross the human blood–brain barrier. In this study, the chemical compositions of five CPEOs were analyzed via gas chromatography–mass spectrometry (GC-MS). CCK8 assays were used to evaluate the ability of five CPEOs to inhibit U251 human glioblastoma cells, and XLB and RA were selected for further investigation. Through wound healing assays and cell cycle and apoptosis analyses via flow cytometry, it was revealed that these CPEOs inhibited cell migration, arrested the cell cycle at G1/G0, and induced apoptosis with similar levels of inhibition. After CPEOs treatment, the intracellular Ca²⁺ content and reactive oxygen species levels in U251 cells increased significantly, whereas the mitochondrial membrane potential decreased. Additionally, the antioxidant enzyme system (SOD, POD, CAT, and GR) and the nonenzymatic defense system (GSH) were inhibited, leading to an increase in lipid peroxidation. qRT–PCR indicated the significant upregulation of intracellular calcium ion signaling pathways and the upregulation of mitochondrial apoptosis-related genes. Additionally, the activation of calcicoptosis-related indicators induced by the CPEOs could be reversed by inhibitor treatment, confirming that both of the selected CPEOs inhibit tumors by activating calcicoptosis-related pathways. These findings highlight the immense potential of CPEOs in healthcare and pharmaceutical applications by not only providing a scientific basis for the potential application of CPEOs in the treatment of glioblastoma but also offering new insights for the development of novel antitumor drugs. Full article

Curcumae Longae Rhizoma (CLRh), Curcumae Radix (CRa), and Curcumae Rhizoma (CRh), derived from the different medicinal parts of the Curcuma species, are blood-activating analgesics commonly used for promoting blood circulation and relieving pain. Due to their certain similarities in chemical composition and pharmacological effects, these three herbs exhibit a high risk associated with mixing and indiscriminate use. The diverse methods used for distinguishing the medicinal origins are complex, time-consuming, and limited to intraspecific differentiation, which are not suitable for rapid and systematic identification. We developed a rapid analysis method for identification of affinis and different medicinal materials using attenuated total reflection-Fourier-transform infrared spectroscopy (ATR-FTIR) combined with machine learning algorithms. The original spectroscopic data were pretreated using derivatives, standard normal variate (SNV), multiplicative scatter correction (MSC), and smoothing (S) methods. Among them, 1D + MSC + 13S emerged as the best pretreatment method. Then, t-distributed stochastic neighbor embedding (t-SNE) was applied to visualize the results, and seven kinds of classification models were constructed. The results showed that support vector machine (SVM) modeling was superior to other models and the accuracy of validation and prediction was preferable, with a modeling time of 127.76 s. The established method could be employed to rapidly and effectively distinguish the different origins and parts of Curcuma species and thus provides a technique for rapid quality evaluation of affinis species. Full article