Search Results (145)

The intensifying freshwater crisis underscores the critical need for all-weather, low-energy atmospheric water harvesting technologies. Inspired by the scale-like protrusions and interconnected channels of Tillandsia leaves that enable efficient water capture and release, a polyvinyl alcohol-based foam featuring a three-dimensional porous structure is fabricated using the supercritical carbon dioxide foaming technology. Compared to the traditional freeze-drying method, this approach significantly reduces preparation energy consumption and shortens the production cycle. Lithium chloride integration endows the foam with exceptional moisture absorption capacity, reaching 300% of its weight. Leveraging graphene’s outstanding photothermal conversion properties, the foam achieves a photothermal dehydration rate of 80.7% within 80 min under 1 Sun irradiation, demonstrating a rapid water release capacity. Furthermore, the polyvinyl alcohol-based foam exhibits no performance degradation after 60 cycles, indicating remarkable stability. This technology provides a scalable, low-cost, and all-climate-applicable solution for water-scarce regions. Full article

Wound healing in oral surgery is influenced by systemic conditions (aging, diabetes) and habits (smoking, alcoholism), which can hinder the natural regenerative capacity of the oral mucosa. The human amniotic membrane (hAM), long recognized for its wound-healing properties, has gained attention as a valuable biomaterial in regenerative dentistry. Its biological composition—including epithelial and mesenchymal stem cells, collagen, growth factors, cytokines, and proteins with anti-inflammatory and antimicrobial properties—supports anti-inflammatory, angiogenic, immunomodulatory, and pro-epithelializing effects. These elements work synergistically to enhance tissue repair, reduce scarring, and promote rapid healing. The hAM can be preserved through cryopreservation, dehydration, or freeze-drying, maintaining its structural and functional integrity for diverse clinical uses. In oral surgery, the hAM has been applied with significant success to surgical wound coverage, treatment of periodontal and bone defects, and implant site regeneration, as well as management of complex conditions like medication-related osteonecrosis of the jaw (MRONJ). Clinical studies and meta-analyses support its safety, efficacy, and adaptability. Despite its proven therapeutic benefits, the hAM remains underutilized in dentistry due to challenges related to its preparation and storage. This review aims to highlight its potential and encourage broader clinical adoption in regenerative oral surgical practices. Full article

This study presents a comprehensive design, optimization, and intensification approach for enhancing the energy efficiency of electric grade isopropyl alcohol (IPA) production, a typical energy-intensive chemical process. The process entails preconcentration and dehydration steps, with the intensity of separation formulated from a multicomponent feed that consists of IPA and water, along with other impurities. Modeling and energy optimization were performed for a conventional distillation train as a base case by using the rigorous process simulator Aspen Plus V12.1. To improve energy efficiency, various options for intensifying distillation were examined. The side-stream preconcentration column was subsequently replaced by a dividing wall column (DWC) with two side streams, i.e., a Kaibel column, reducing the total energy consumption of corresponding distillation columns by 9.1% compared to the base case. Further strengthening was achieved by combining two columns in the preconcentration process into a single Kaibel column, resulting in a 22.8% reduction in reboiler duty compared to the base case. Optimization using the response surface methodology identified key operating parameters, such as side-draw positions and stage design, which significantly influence both energy efficiency and separation quality. The intensified Kaibel setup offers significant energy efficiencies and simplified column design, suggesting enormous potential for process intensification in energy-intensive distillation processes at the industrial level, including the IPA purification process. Full article

A green and mild chemical reaction of calcium citrate (CC) was successfully prepared from reactions between mussel shell waste and citric acid in the presence of acetone (AC), ethanol (Et), and isopropyl alcohol (IPA). All the synthesized CCs contained the same functional groups such as citrate (C₆H₅O₇³⁻), water (H₂O), and calcium–oxygen (Ca–O). However, the differences in the spectra pointed out the differences in the crystal environment and structure of CCs. CC-AC and CC-IPA mainly crystallized in the monoclinic [Ca₃(C₆H₅O₇)₂(H₂O)₂]·2H₂O crystal system, whereas CC-Et mainly crystallized in the triclinic Ca₃(C₆H₅O₇)₂∙(H₂O)₄ structure. The molecular alignments of triclinic CC-Et were different from monoclinic CC-AC and CC-IPA, resulting in differences in thermal behaviors. Two dehydration steps were observed for the monoclinic CC-AC and CC-IPA, whereas the triclinic CC-Et showed a single dehydration process. The TG mass losses further demonstrated that anhydrous Ca₃(C₆H₅O₇)₂ phase, in addition to the Ca₃(C₆H₅O₇)₂∙4H₂O, was also observed for CC-AC and CC-IPA, whereas CC-Et contained a single Ca₃(C₆H₅O₇)₂∙(H₂O)₄ phase. The morphologies of CC-AC and CC-IPA also differed from that of CC-Et. The differences in some properties of the synthesized CCs could be attributed to the change in the supersaturation state of the reaction solution. Due to the superior polarity, ethanol is more compatible with citric acid. The presence of ethanol could suppress the supersaturation rate of the reaction solution, causing the modulation of the precipitation mechanisms and reducing the particle growth rate of CC-Et, thereby explaining the difference in vibrational, structural, thermal, and morphological characteristics of CC-Et, compared to CC-AC and CC-IPA. Full article

Investigations of the synthesis of multicomponent coatings and their subsequent application to metal substrates to increase the wear resistance of materials is relevant for industry. Nickel compounds obtained from oxidized magnesia-iron nickel ores with a desorption rate of more than 94% were used to create Ni-MoO₃-WO₃ electroplating. Such composite samples formed from an aqueous alcohol solution reduced the content of sodium and ammonium chlorides. The annealing and dehydration of samples at a temperature of 725 °C in an air atmosphere made it possible to achieve the highest level of crystallinity. In this case, an isomorphic substitution of W atoms by Mo occurs, which is confirmed by electron paramagnetic resonance (EPR) spectroscopy studies. The invariance of the shape of the EPR spectrum with a sequential increase in microwave radiation power revealed the stability of the bonds between the particles. The surface morphology of Ni-MoO₃-WO₃ films deposited on an Al substrate is smooth and has low roughness. In this case, an increased degree of wear resistance has been achieved. Thus, a recipe for the formation of an electroplating with stable bonds between the components and increased wear resistance was obtained. Full article

In the production process of the heavy oil industry, efficiently demulsifying water-in-heavy oil (W/HO) emulsions can effectively prevent the negative effects of emulsion corrosion on equipment, increase costs, reduce oil quality, and pollute the environment. Herein, polyether demulsifier complexes (PDC) were obtained by compounding fatty alcohol nonionic polyether (FAP) with perfluoropolyether (PFPEA, [CF₃O(CF₂CF₂O)_nCF₃]) through a simple physical blending method. The experimental results demonstrate that PDC exhibited outstanding demulsification performance for W/HO emulsions across varying temperatures: At 60 °C and 400 ppm dosage, PDC achieved complete dehydration (100%) within just 2 min, showing significantly faster demulsification kinetics compared to FAP and PFPEA. Even at the reduced temperature of 40 °C, PDC maintained effective demulsification capability, achieving complete phase separation within 6 min. These findings collectively establish PDC’s superior demulsification efficiency for W/HO emulsions, with particularly remarkable performance under challenging low-temperature conditions. Research on the demulsification mechanism indicates that PDC achieves efficient demulsification performance due to the synergistic effect the synergistic effect of FAP and PFPEA to effectively destroy the non-covalent bonds (hydrogen and π–π stacking) of interfacially active asphaltenes (IAA) at the oil–water interface, thereby achieving demulsification of W/HO emulsion. PDC with outstanding demulsification ability exhibits significant potential for practical applications in heavy crude oil–water emulsion treatment, and this work can provide insights for developing new composite demulsifiers for petroleum production. Full article

This paper aims to explore the impact of targeted viticultural and enological interventions on reducing the astringency of wines made solely with Mandilaria, a red Vitis Vinifera L. grape variety. Mandilaria is characterized by its high berry density, high tannin content, intense color and full body profile, all of which contribute to the distinctive enological characteristics of the wines while also pretending challenges for producers during vinification. This research aims to improve phenolic ripeness and adapt the wine produced to the requirements of the present consumers demands. In the vineyards of Paros Island, different intensities of leaf removal and modifications to pruning load were applied. Three distinct post-harvest grape dehydration techniques and two varying levels of seed removal during alcoholic fermentation were evaluated for their effectiveness in reducing astringency. Sensory analysis with a trained panel was also performed. The results demonstrate that post-harvest dehydration techniques, particularly air and sun dehydration, significantly influence the quality indicators of Mandilaria wines, enhancing the phenolic content, tannin levels and antioxidant activity, while also improving the phenolic ripeness and reducing the harsh tannic profile. Furthermore, seed removal effectively diminished astringency without affecting the wine’s structure. These findings suggest that the integration of these viticultural and enological techniques can significantly enhance the sensory attributes of Mandilaria wines, making them more appealing to modern consumers. Full article

Conventional mild hydrotreatment processes of bio-oil present significant challenges of a high degree of polymerization, a low oil yield, high coke formation, and poor catalyst recovery. To address these challenges, the current study looked into investigating and enhancing the properties of raw bio-oil organic phase samples via a solvent-assisted stabilization approach using methanol (METH), ethanol (ETH), isopropyl alcohol (IPA), and ethyl ether (DME). Solvents like methanol (METH) and ethanol (ETH), which are highly polar, yielded higher oil fractions (64% and 62%, respectively) compared to less polar solvents like ethyl ether (DME) at 59%. Isopropyl alcohol (IPA), with intermediate polarity, achieved a balanced oil yield of 63%, indicating its ability to dissolve both polar and non-polar components. Moisture reduction in stabilized bio-oils followed the order IPA > ETH > METH > DME, with IPA showing the highest reduction due to its structural characteristics facilitating dehydration. Viscosity reduction varied, with IPA > ETH > DME > METH. Carbon recovery in stabilized bio-oils ranged from 65% to 75% for DME, ETH, and METH and was 71% for IPA. The heating values of stabilized bio-oils ranged from 28 to 29 MJ/kg, with IPA-stabilized bio-oil showing the highest value (29.05 ± 0.06 MJ/kg). METH demonstrated high efficiency (74.8%) in stabilizing bio-oil, attributed to its strong hydrogen-donating capability. ETH followed closely at 69.5%, indicating its comparable performance in bio-oil stabilization. With moderate efficiency (69.3%), IPA presents a balanced alternative considering its molecular structure and hydrogen solubility. In contrast, DME exhibited lower efficiency (63.6%) due to its weaker hydrogenation capability and propensity for undesired side reactions. The current study suggests that subcritical conditions up to 200 °C are adequate for METH, ETH, and IPA in bio-oil stabilization, comparable to results obtained under supercritical conditions. Full article

Background/Objectives: Hydration and nutrition are two key aspects of high-quality athletic performance. However, little is known about the potential beneficial effects of functional foods in sports. The present study investigates the hydration statuses of and knowledge, dietary habits, and consumption of functional foods among football athletes, both professional (n = 24) and non-professional (n = 20). Methods: The study sample had a mean age of 19.9 ± 4.9 years, a mean weight of 74.0 ± 6.0 kg, and a mean body mass index (BMI) of 23.0 ± 1.40 km/m². All the athletes filled out a questionnaire about their hydration knowledge regarding sports and a functional food consumption questionnaire. Hydration status was assessed through urine color (Ucol) before and after training. Results: The results of this study show that 65% of the non-professional and 59.1% of the professional football players started their training dehydrated, and this proportion increased to 73.7% at the end of the training. Moreover, >50% of athletes were poorly educated in hydration practices during and after exercise. In addition, nutritional habits differences were observed among the professional and non-professional athletes regarding alcohol consumption (p < 0.0001) and fries (p < 0.05). Conclusions: A comprehensive understanding of and tailored approaches to nutrition and hydration need to be promoted among football athletes to realize the benefits of hydration and nutritional strategies that optimize their physiological resilience and competitive edges. Full article

Polybutylene succinate (PBS) is a biodegradable aliphatic polyester with excellent thermal stability, mechanical properties, and processability. The synthesis of PBS typically employs titanium-based catalysts like tetrabutyl titanate (TBT) to accelerate the reaction. However, TBT acts as a homogeneous catalyst and is non-recyclable. This study aims to minimize the cost of recovering liquid TBT catalyst during PBS synthesis by using TBT-loaded activated carbon for direct esterification and optimizing the process conditions. The catalyst was analyzed using inductively coupled plasma emission spectroscopy, automated specific surface area and pore size analysis, X-ray diffraction, and Fourier-transform infrared spectroscopy. The product was evaluated through infrared spectroscopy, nuclear magnetic resonance hydrogen spectra, and gel permeation chromatography. The optimal process parameters were determined to be an esterification temperature of 170 °C, a polycondensation temperature of 235 °C, an acid-to-alcohol molar ratio of 1:1.2, a catalyst amount of 0.06 g, and a dehydration time of 3 h. Under these conditions, the weight-average molecular weight of PBS reached 47,655, reducing the catalyst usage from 0.5% to 0.3%, resulting in a 24.7% increase in catalytic efficiency compared to TBT, significantly lowering costs. After five cycles of reuse, the weight-average molecular weight of the product remained above 35,000. This study demonstrates that TBT-loaded activated carbon exhibits superior catalytic performance, offering a cost-effective and efficient method for industrial PBS production with broad application potential. Full article

Herbal teas made from agricultural waste or by-products are gaining attention as eco-friendly alternatives to support circular economy practices. Fig (Ficus carica L.) leaves are well known for their biological activities. The research aims to investigate the possibility of using fig waste leaves to produce healthy and sustainable herbal teas. Different drying technologies have been used, including air drying (AD) and microwave drying (MWD), and consumer acceptability was tested and related to the sensory features and volatile odor compounds. Sensory descriptive analysis and hedonic consumer tests were carried out. Odor volatiles were analyzed by headspace–solid-phase microextraction–mass spectrometry–gas chromatography (HS-SPME-GC-MS). The teas were also evaluated for their phenolic content and antioxidant capacity. Results indicate that MWD increases the total phenolic compound amount by 20%, reduces C6 alcohols and aldehydes responsible for green and herbaceous sensory notes, and increases pentanal, octanal, nonanal, ketones (especially 6 methyl-5-hepten-2-one) and terpenes, such as β-cyclocitral, which are related to the fruity and honey odors; this leads to a more appreciated color and taste. This study demonstrated that dehydrated fig waste leaves, especially those processed through the eco-friendly microwave drying method, can be utilized to produce herbal teas with favorable sensory and nutritional properties. This approach aligns with sustainability objectives and presents a promising strategy for diversifying the herbal tea market while promoting the valorization of agricultural wastes. Full article

A concise, transition metal-free four-step synthetic pathway has been developed for the synthesis of tetracyclic heterosteroidal compounds, 14-aza-12-oxasteroids, starting from readily available 2-naphthol analogues. After conversion of 2-naphthols to 2-naphthylamines by the Bucherer reaction, subsequent selective C-acetylation was achieved via the Sugasawa reaction and reduction of the acetyl group using borohydride, which resulted into the corresponding amino-alcohols. The naphthalene-based amino-alcohols underwent double dehydrations and double intramolecular cyclization with oxo-acids leading to one-pot formation of a C-N bond, a C-O bond and an amide bond in tandem, to generate two additional rings completing the steroidal framework. A series of 14-aza-12-oxasteroids were synthesized using our developed synthetic strategy in moderate yields, and the structure of one of the final products, 12a-Methyl-11-phenyl-11,12a-dihydro-1H-naphtho[2,1-d]pyrrolo[2,1-b][1,3]oxazin-3(2H)-one, was further confirmed by single crystal X-ray crystallography. Full article

Ethanol production by fermentation results in obtaining, in addition to the main product, ethyl alcohol, by-products and secondary products, which include carbon dioxide, fusel oil, and ester–aldehyde cut. Fusel oil, despite its low yield and the large volume of ethanol production, accumulates at distilleries, which ultimately raises the question of its disposal or the rational use of this by-product. Fusel oil, being a complex mixture, can serve as a source of technical alcohols used in various sectors of the economy, including the food industry, pharmaceuticals, organic synthesis, perfume, and cosmetics industries, as well as the production of paints and varnishes. However, the complexity of using fusel oil lies in its difficult separation. The reason for this is the presence of water, which forms low-boiling azeotropes with aliphatic alcohols. Our study aimed to develop a process flow diagram (PFD) that allows individual components from fusel oil to be obtained without extraneous separating agents (not inherent in fusel oil). This condition is necessary to obtain products labeled as natural for further use in the food, perfume, cosmetic, and pharmaceutical industries. The distinctive feature of this work is that the target product is not only isoamyl alcohol but also all other alcohols present in the composition of fusel oil. To achieve this goal and create a mathematical model, the Aspen Plus V14 application, the Non-Random Two Liquid (NRTL) thermodynamic model, and the Vap-Liq/Liq-Liq phase equilibrium were used. Fusel oil separation was modeled using a continuous separation PFD to obtain ethanol, water, isoamyl alcohol, and raw propanol and butanol cuts. The Sorel and Barbet distillation technique was used to isolate ethanol. The isolation of isopropanol and 1-propanol, as well as isobutanol and 1-butanol, was modeled using the batch distillation method. The isolation of fusel oil components was based on their thermodynamic properties and the selection of appropriate techniques for their separation, such as extraction, distillation, pressure swing distillation, and decantation. The simulation of fusel oil separation PFD showed the possibility of obtaining the components of a complex mixture without separating agents, as discussed earlier. Ethanol corresponds to the quality of rectified ethyl alcohol, and 1-butanol and isoamyl alcohols to anhydrous alcohols, whereas isopropanol (which contains an admixture of ethanol), 1-propanol, and isobutanol are obtained as aqueous solutions of different concentrations of alcohols. However, due to a distillation boundary in the raw propanol and butanol cuts, these mixtures cannot be separated completely, which leads to the production of intermediate fractions. To eliminate intermediate fractions and obtain anhydrous isopropanol, 1-propanol, and isobutanol in the future, it is necessary to solve the dehydration problem of either fusel oil or the propanol–butanol mixture. Full article

Strategies followed to improve SBA-15 surface (essentially inert) included modifications by adding acidic or basic (or both) species during or after silica synthesis. Amphoteric properties are especially important, as some reactions (alcohol dehydration, for instance) require both types of sites to efficiently take place. In this work, single Zr (nominal 3, 5, and 10 wt%, as ZrOCl₂•8H₂O) direct addition during SBA-15 synthesis was used to impart amphoteric characteristics (as determined by NH₃ and CO₂ TPD) to mesostructured SiO₂ matrices. Additional materials characterization included textural (N₂ physisorption) and structural (XRD, FTIR, and UV–Vis spectroscopies, and HRTEM as well) studies. Actual solids composition was also determined (EDS). The degree of Zr incorporation into mesoporous silica was enhanced with nominal content in binary formulations, although not necessarily integrated into SBA-15 walls forming Zr-O-Si linkages. It seemed that single ZrO₂ domains (framework and extra-framework) could provide suitable amphoteric properties by significantly increasing the number and strength of both acid and basic sites (especially formulations containing nominal 5 wt% Zr), as to those over mesostructured silica matrices. Also, potentially deleterious strong acid sites were avoided. The binary oxides present great potential to be applied in reactions requiring vicinal acid–base pairs (alcohol dehydration, for instance). Full article

The use of activated carbon-based catalysts for the production of solketal and γ-valerolactone (GVL), two products of interest for biorefinery processes, was investigated. Activated carbons (ACs) were prepared by chemical activation of olive stones, an agricultural byproduct, using H₃PO₄ to olive stone mass impregnation ratios (IRs) of 1:1 and 3:1, and under nitrogen or air atmosphere. The ACs showed S_BET values of 1130–1515 m²/g, owing to the presence of micropores (0.45–0.60 cm³/g). The use of an IR of 3:1 delivered a wider pore size distribution, with mesopore volume increasing up to 1.36 cm³/g. XPS confirmed the presence of phosphorus groups with surface concentrations of 2.2–3.2 wt% strongly bonded the AC surface through C-O-P bonds. The ACs were tested as acid catalysts for the acetalization of glycerol in a stirred batch reactor at temperatures of 30–50 °C, glycerol concentrations of 1.5 to 3.4 mol/L, and 1–3 wt% catalytic loading. The catalytic activity was clearly correlated with the quantity of C-O-P acid groups determined by TPD, which increased when ACs were prepared under air atmosphere. The AC prepared with IR 3:1 under air achieved full selectivity to solketal, with activation energy of 49 kJ/mol and conversion of up to 70%, matching the equilibrium conversion value under the optimum reaction conditions. A bifunctional catalyst was prepared over this AC by deposition of 5 wt% zirconium and tested in stirred batch reactor for the hydrogenation of levulinic acid (LA) using isopropyl alcohol (IPA) as solvent and H₂ donor, with LA:IPA ratios from 1:1 to 1:7 and temperatures between 160–200 °C. The catalyst reached full LA conversion and a GVL yield higher than 80% after only 12 h at 200 °C. A test conducted in the presence of water revealed that it was an inhibitor of the reaction. The identification of isopropyl levulinate as an intermediate suggests that the most likely reaction pathway was dehydration, followed by hydrogenation and cyclization, to obtain GVL. Kinetic modelling of the results showed a value of 42 kJ/mol for the hydrogenation step. The reusability of the catalyst was tested for five consecutive reaction cycles, maintaining most of the activity and selectivity towards GVL. Full article