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Herein, the effectiveness of different amounts of highly active bimetallic FeMn catalysts (5, 10, and 20 Si/bimetal mole %) for water contaminant elimination was elucidated. The catalysts were immobilized on cage-like SBA-16 supports using the impregnation method. The Fe:Mn ratio was kept constant at 1:1 for all the catalysts. To characterize the synthesized catalysts, N2 adsorption–desorption analysis was performed in order to study the structure of the catalysts. XRD was used to examine the crystal structure, while SEM, EDS, and mapping techniques were employed to investigate the morphology and distribution of the bimetal on the support. To evaluate the activity of the catalysts in removing water contaminants, three different dyes, namely Methyl Orange (MO), Orange (II) (O(II)), and Methylene Blue (MB), were selected. The influence of the amount of bimetal loaded on the support, catalyst dosage, H2O2 concentration, and pH variation was investigated on the dye removal process in order to find the best operational condition for efficient dye degradation. Based on the experimental data, the catalyst with 5% FeMn on SBA-16 was determined to be the most effective catalyst with 87% degradation of MO, 99.8% of O(II), and 99.9% of MB using a catalyst dosage of 0.5 g/L, an H2O2 concentration of 0.98 mM, and a pH of 4. Overall, this research highlights the synthesis and characterization of bimetallic FeMn codoped SBA-16 catalyst, and their effectiveness in removing water contaminants, as demonstrated by the degradation of various dyes under specific operational conditions. [ABSTRACT FROM AUTHOR]

Weight percent gain (WPG) is used as an index of the quantity of impregnated resin into wood. It is well‐known that the maximum value of WPG is roughly calculated using the volume of cell lumen included in wood. In this study, we proposed the theoretical formula that calculates the maximum value of WPG (W-value), with higher accuracy by considering the cell wall swelling and resin concentration distribution as well as the cell-lumen volume. In this paper, the WPG of wood for six softwood species was measured after the injection with phenol–formaldehyde resin solution and after the subsequent conditioning and drying. The measured WPG values after each process were successfully explained by the W-value calculated using the theoretical formula. It was suggested from the calculation that the WPG was greatly influenced by the cell wall swelling and by the difference in solution concentration between the cell lumen and the transient pore in the cell wall. The influences were also suggested to be larger for wood with higher density. [ABSTRACT FROM AUTHOR]

In recent years, impregnation of biomaterial (wood veneers) with eutectic phase change materials (PCM) has been investigated to increase the thermal capacity of bio-based materials, which significantly affects the thermal capacity, especially in building applications requiring low heat. In this study, four eutectic phase change materials were prepared using three different fatty acids and impregnated on two wood veneers (oak and ash). The structural characterization of the prepared eutectic mixtures was examined using FT-IR, while the morphological properties of the wood veneers were examined by scanning electron microscopy (SEM). The thermal performance was analyzed via differential scanning calorimetry (DSC) and their thermo-mechanical properties by dynamic mechanical analysis (DMA). Additionally, the thermal conductivity (k values) was determined. From the results obtained, it was possible to prepare eutectic mixtures with melting temperatures around 30°C with heat capacities up to 225.5 J/g. It was also generally determined that eutectic PCM, prepared from mixtures of lauric acid and palmitic acid, have lower thermal conductivity but show higher storage and loss modulus for the wood coatings leading to a balance between mechanical and thermal properties. [ABSTRACT FROM AUTHOR]

The utilization of continuous fiber‐reinforced thermoplastic composites (CFRTP) in additive manufacturing technology (AM) is envisioned to enable the production of high‐performance parts with enhanced mechanical properties. In the production of CFRTP filaments, ensuring proper impregnation plays a crucial role in improving the characteristics of the produced filament. Carbon fiber (CF) reinforced polyphenylene sulfide (PPS) composites find applications in secondary aerospace parts, automotive structural parts, and chemical process applications. Continuous CF‐reinforced PPS filaments enable the production of lightweight, high‐performance parts with mechanical strength, heat, and chemical resistance in AM. In the present study, continuous CF‐reinforced PPS filaments were produced using the melt impregnation method for use in fused deposition modeling technology. Filament diameter, geometrical evenness, and effective fiber impregnation are important criteria in filament production. An impregnation mold was designed and manufactured to provide impregnation. The influence of three different pin angles (56°, 70°, and 82°) on impregnation and mechanical properties has been investigated by developing an impregnation die for CFRTP filament production. Tensile testing, fiber content analysis, optical microscopy, and scanning electron microscope analysis were performed on the produced filaments. Furthermore, increasing the pin angle leads to an increase in both the spreading and impregnation of fibers. Highlights: Impregnation die for effective wetting of fibers with polymer.Significance of pin angle in fiber spreading and wetting with polymer.Application of test standards for fiber content. [ABSTRACT FROM AUTHOR]

Owing to the intensive development of electrical and electronic equipment, there is an increasing demand for precious metals, which are often used for its production. Due to their scarce supply, it is important to recover them from secondary sources. A promising way to recover precious metals are impregnated resins. In this research, Amberlite XAD-16 was impregnated with TBP at the weight ratios of 1:2 and 1:3 using the 'warm impregnation' method. Studies were carried out on the sorption of Au(III), Pd(II), Pt(IV), and Rh(III) ions from the model chloride solutions as well as the real solution formed after leaching the smart card chips. Only Au(III) ions were efficiently sorbed on the prepared impregnated sorbents. The best results were obtained at 6 M HCl and the sorbent mass: 0.1 g/25 mL. The maximum sorption capacity for the impregnated sorbents was: 147.91 mg/g (ratio 1:2) and 149.66 mg/g (ratio 1:3). Recovery of Au(III) ions from the real leaching solution was: 97.36% and 97.77%, respectively. The Langmuir isotherm was the best-fit model for the experimental results. Thermodynamic studies proved that the investigated sorption process is spontaneous and exothermic. The desorption process can be easily carried out with 1 M HCl/1 M TU. [ABSTRACT FROM AUTHOR]

Herein, a novel approach was developed for the introduction of stabilizing compounds into polymers through a pre-impregnation process prior to processing, which is expected to improve their dispersion and, consequently, increase their efficacy. Ethylene-norbornene copolymer (EN) pellets were impregnated with quercetin or rutin in ethanol or a mixture of solvents (ethanol-dioxane (3:1)) for 24 h. Then, EN-based samples containing impregnated pellets were manufactured using a laboratory extruder. The research demonstrated that the materials containing impregnated pellets exhibited improved thermo-oxidation resistance, higher antibacterial effect (the number of dead cells increased from 8 to 59%), and satisfactory photostability. This may be a direct result of their better dispersion degree and their more gradual, controlled release from the EN during operation. If we compare the stabilizing effect of both polyphenols, quercetin was more efficient, which may be attributed to the presence of hydroxyl group at the C3 position in the C ring, which could increase the reactivity of the catechol structure of the B ring. The proposed approach effectively solves the issues that arise during the commonly used processing techniques and may facilitate the broader utilization of natural stabilizers in the polymer industry. [ABSTRACT FROM AUTHOR]

High mercury levels from industrial and natural sources necessitate effective water mercury removal methods owing to human and ecosystem toxicity risks. This study addresses the adsorption of Hg ions onto mixed-valent magnetite nanoparticles (MNPs) owing to their high surface area, reactivity, and magnetic recovery ability. The adsorption capacity of MNPs is influenced by the morphological characteristics. The influence of the vegetable fiber surface charge in magnetite, along with the change in pH, on the Hg ion adsorption process by MNPs remains an open question. The adsorption capacities of the synthesized MNPs and Cabuya fibers (Agave Americana L. ASPARAGACEAE) impregnated with magnetite nanoparticles (FC-MNPs) were compared. The synthesis and impregnation of MNps were performed using the chemical coprecipitation method with ferrous and ferric chloride as precursor solutions. The composition, surface properties, and morphology of the synthesized adsorbents were investigated by scanning electron microscopy (SEM) coupled with an energy dispersive X-ray spectrometer (EDS), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and Raman spectroscopy (RS), which provided evidence that MNps reached an approximate diameter of 19 nm. Both adsorbents were used for the removal of Hg (II) at different initial pH values, times, temperatures, adsorbent dosages, and analyte concentrations. FC-MNPs and MNPs were able to achieve approximately 93% and 83% Hg (II) removal, respectively, under the following experimental conditions: the adsorbent dose 0.5 g, Hg (II) 10 mg/L, pH 5.0, stirring speed of 150 rpm, temperature of 25 °C, and equilibrium time of 4 h. Equilibrium data were evaluated by fitting the Langmuir and Freundlich isotherm models to the experimental conditions. Additionally, kinetic studies of pseudo-first and pseudo-second order were conducted to understand the mechanism of interaction between the adsorbent and the metal ions. The results show that FC-MNPs has a maximum adsorption capacity of Hg(II) of 4.95 mg/g of adsorbent, and that the reaction system follows pseudo-second order kinetics and the Freundlich isotherm model. Finally, the experimental results reported in this work show that cabuya fibers impregnated with MNPs have an important impact on the immobilization of aqueous contaminants. This offers a new method for developing novel nanocomposite adsorbents for the removal of metallic ions from wastewater. [ABSTRACT FROM AUTHOR]

The valorization of Amazonian wood residues into active chemical compounds could be an eco-friendly, cost-effective and valuable way to develop wood preservative formulations to enhance the decay and termite resistance of low-durable wood species. Wacapou (Vouacapoua americana., Fabaceae) is a well-known Guianese wood species commonly used in local wood construction due to its outstanding natural durability, which results from the presence of a large panel of extractives compounds. In addition, its industrial processing generates large amounts of residues. Wacapou residues were extracted by maceration using four different solvents (water/ethanol, ethyl acetate, hexane and dichloromethane/methanol), separately and successively. The yield of each extractive fraction was determined, and their chemical compositions were analyzed by Liquid Chromatography-Mass Spectrometry (LC-MS). Ethyl acetate led to the highest extraction yield, and the active compounds were identified in the obtained extractive fraction. In this sense, the fungicidal and termite-repellent properties of these extractives were then tested using a screening laboratory (with temperate and tropical microorganisms), according to the solution concentration (1%, 2.5%, 5%, 8% and 10%). Finally, Virola michelii Heckel wood samples (low durable species) were impregnated with the 8% concentration solution. The impregnated wood samples were then exposed to a soil bed test. The results highlighted that the nature of the solvent used during wood maceration affects the content of the obtained extractive fractions. Ultra-Performance Liquid Chromatography–High-Resolution Mass Spectrometry (UHPLC-HRMS) analyses showed the influence of extraction parameters on the nature of the extracted molecules. Wacapou extracts (from ethyl acetate maceration) showed good anti-fungal and anti-termite activities. Additionally, the concentration in extractives had an impact on the anti-termite activity level for Reticulitermes flavipes and Cryptotermes sp. Formulations based on Wacapou extractives showed a good potential for valorization in eco-friendly preservatives, aiming to confer better durability to local low-durability wood species. [ABSTRACT FROM AUTHOR]

Herein, we prepared functional chitosan films reinforced with chitin nanocrystals by supercritical solvent impregnation with a variety of essential oils, i.e. mentha, clove, and cinnamon. Two different chitosan film structures were evaluated, smooth and compact films obtained by casting; and highly porous films prepared by lyophilization process. The effect of the film morphology, essential oil impregnation and the presence of chitin nanowhiskers on the properties of the films were extensively investigated by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and tensile testing; while the bioactive functions were evaluated by measuring the antioxidant and antimicrobial activities. It was found that the impregnation of essential oils is much higher in porous films, confering notable antioxidant and antimicrobial activity. The incorporation of chitin nanocrystal does not influence on the impregnation process, and only improves slightly the antioxidant performance, which is clearly appreciable in the case of films obtained by casting with an increase of ca. 35% from chitosan without to samples with 5 wt% of chitin nanowhiskers. Nevertheless, an important enhancement of the mechanical properties, particularly in elastic modulus, is clearly appreciated with the incorporation of chitin nanowhisker into the films, with values of 50% higher in comparison with chitosan without nanowishers. However, the elongation at break and tensile strength values suffer a slight decrease. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells (SOFCs) are regarded as attractive electrochemical energy conversion devices owing to their exceptional efficiencies and superb fuel flexibility. However, their widespread implementations are remarkably restricted by the inferior sulfur tolerance of state-of-the-art nickel-based cermet anodes under practical conditions. Herein, a layered NaLaTiO 4 (NLTO) perovskite oxide with Ruddlesden-Popper structure is designed as a new anode for SOFCs operating on sulfur-containing fuels. After impregnating NLTO into a samaria-doped ceria (SDC) scaffold, such impregnated nanocomposite anode exhibits high electrochemical activity, sulfur tolerance and stability in H 2 S-containing fuels due to the polar layered structure, abundant oxygen vacancies, superior surface basicity and water storage capability, leading to the efficient removal of the deposited/adsorbed sulfur on the surface of this nanocomposite anode. The electrochemical activity of the NLTO-based composite anode for fuel oxidation is further improved by adding nickel nanoparticles through impregnation, showing enhanced power outputs and considerable operational stability in H 2 S-containing fuels. This study provides a new, high-performing and sulfur-resistant anode for SOFCs, which may promote the commercialization of this technology. [Display omitted] • Ruddlesden-Popper perovskite anode (NaLaTiO 4 , NLTO) is designed for solid oxide fuel cells. • The NLTO-infiltrated anode shows high sulfur tolerance due to the polar layered structure. • The NLTO-infiltrated anode also displays high water storage capability and surface basicity. • The cell with NLTO-infiltrated anode exhibits enhanced power outputs in 500 ppm H 2 S-H 2. • The cell with NLTO-infiltrated anode delivers superb operational stability in 500 ppm H 2 S-H 2. [ABSTRACT FROM AUTHOR]

This study aimed to prepare ceramic membranes from low-cost materials for oil/water separation. TiO2 was incorporated into fly ash/kaolin-based ceramic membrane matrix via the impregnation method to enhance membrane performance. The scanning electron microscope (SEM) results exhibited random distribution of pores along the membrane surface with an estimated pore size of 0.001-0.13 µm. The porosity of the TiO2-incorporated fly ash/kaolin ceramic membrane ranged from 42.82%-50.22%, where the sintering temperature played an important role in the water absorption and porosity properties. The X-ray diffraction (XRD) pattern showed an orthorhombic kyanite phase with the presence of three characteristic peaks at 2θ of 26.30°: 27.87° and 35.90°. The XRD pattern of all formulated membranes showed almost no change, however, the crystal intensity varied due to the different ceramic compositions. P hysicochemical properties evaluation showed that the membrane with fly ash, kaolin, and alumina of 20: 30: 40 wt% has reached the best characteristic. The casted membrane with a compaction pressure of 30 bar with sintering temperature of 1200oC for 7 h had the highest compressive strength. The performance showed that the TiO2 incorporated membrane achieved over 95% oil rejection efficiency and significant decrease of several parameters such as Pb, Fe, Mn, nitrate, nitrite, total dissolved solid (TDS), Cl and total organic matter without sacrificing the permeate water flux up to 116 L/m2/h. These experimental results suggest that the TiO2-incorporated Fly ash/kaolin ceramic membrane has great potential for reclaiming oily wastewater into clean water. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of microwave irradiation on the impregnation efficiency of zinc onto pulverized shrimp shell waste. Prior to impregnation, the pulverized shrimp shell was heat treated at 350, 450, and 550 oC for 1, 2 and 3 hours. After each treatment, the treated pulverized shrimp shell was immediately quenched in liquid nitrogen. Microwave-assisted impregnations were carried out at 80 oC for 10, 20, and 30 minutes and at 50% and 100% of the maximum delivery power rate of the laboratory microwave equipment. The resulting impregnated solids were characterized via TGA, DTA, FTIR, SEM, and XRD. Semi-quantitative measurement of the impregnated zinc was determined based on XRF analysis. The BET analysis of the original pulverized shrimp shell waste provided a surface area of 1.273 m2/g and achieved 30.423 m2/g after 550 oC for 3h heating treatment. An increase in crystallinity index was detected as the pulverized shrimp shell waste was exposed to higher and prolonged heating temperatures. Statistical analysis showed no significant difference (p = 0.05) in impregnated zinc levels among the heat-treated pulverized shrimp shells for the same power output of microwave energy. However, a significant difference was obtained between 50% and 100% power output, of which the latter can impregnate two-fold higher levels of zinc than the former. The results of this study concluded that the microwave-assisted technique might potentially be applied for metal impregnation for the preparation of heterogeneous catalysts, and the power strength of the microwave plays a prominent role in metal impregnation. [ABSTRACT FROM AUTHOR]

Mercury (Hg0) emission from coal‐fired industrial plants poses severe threats to ecosystem sustainability and human health, urging the development of novel and cost‐effective adsorbents to treat industrial flue gas. Herein, the modification of industrial residual red mud (RM) through the impregnation of hydrogen halides (HH) and its adsorption characteristics for removing elemental mercury from combustion flue gas was reported. Experimental investigation of HH‐modified RM reveals that the hydrogen iodide (HI)‐modified RM with a concentration of 1.5 M had a maximum Hg0 removal efficiency of 98%, whereas hydrogen bromide (HBr) 1.5 M modified RM had a maximum Hg0 removal efficiency of 90%. The effect of various parameters, such as reaction temperature and halide concentrations, were also found to be influential for the adsorption efficiency of the modified RM. Moreover, it is important to highlight the chemisorption characteristics of HI‐modified RM, which significantly enhances the efficiency of the removal process. The Hg0 removal efficiency increases with the increase in HI concentration (1.5 M @ 93%) with an optimal reaction temperature of 140°C. Furthermore, the maximum Hg0 removal attained with a change in NO concentration was 98% at 200 ppm. However, increasing the SO2 concentration reduces the efficiency of RM for removing Hg0 in simulated coal combustion flue gas. The pseudo‐second‐order model (R2 = 0.98) accurately describes the adsorption of in kinetic investigations, indicating a chemisorption mechanism. This analysis of the chemisorption mechanism highlights the efficiency of halide‐modified industrial solid waste, which has the potential to be used in the design of economical and innovative adsorbents for reducing environmental pollution. The present study employed specific reaction parameters such as reaction temperature, halide loading contents, and different flue gas compositions, which had not been extensively explored. [ABSTRACT FROM AUTHOR]

Silver nanoparticles have garnered significant attention for their antimicrobial applications. The aim of this study was to develop and characterize a silver nanoparticle-enhanced bone graft and assess its antimicrobial and antibiofilm activities. Bone granules from bovine cancellous femur were impregnated with silver nanoparticles (50 nm). The antimicrobial and antibiofilm activity was tested against various pathogens, including Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Enterococcus faecalis, Acinetobacter baumannii, and Escherichia coli. Biocompatibility and resorption were evaluated in a mouse calvaria model. All the tested pathogens showed susceptibility to silver nanoparticles, with minimal inhibitory concentrations ranging from 0.25 to 4 mg/L. The silver nanoparticle scaffolds demonstrated a significant reduction in biofilm formation across all microorganisms. The graft exhibited a biocompatibility comparable to that of autologous bone, with reduced resorption rates. Additionally, the presence of nanoparticles did not impact radiolucency, and cytotoxicity remained minimal. Bone grafts impregnated with silver nanoparticles effectively reduce biofilm formation, suggesting their potential as a strategic material for various implant applications. [ABSTRACT FROM AUTHOR]

High-performing zeolite materials for carbon dioxide capture are promising for applications such as flue gas CO2 capture. Potassium carbonate–loaded zeolites can offer a plethora of benefits. In this work, for the first time, zeolite-Y impregnated with K2CO3 was studied as a gas adsorbent (CO2, CH4, and N2) and characterized using TGA (thermogravimetric analyzer), XRD, BET, FTIR, FETEM (Field-Emission Transmission Electron Microscope), and XPS. The effect of carbonate loading, temperature, and pressure was particularly targeted and assessed. Accordingly, for a variation in K2CO3 loading from 5 to 15 wt.%, the CO2 adsorption capacity reduced from 3.61 to 1.73 mmol g−1 in the synthesized adsorbents. Among all the cases, KYZC10 exhibited very good cyclic adsorption–desorption performance and thermal stability. Further equilibrium modeling studies indicate that the stable and optimally K2CO3-loaded adsorbent (KYZC10) demonstrates effective adsorption isotherm behavior, making it suitable for different temperature variation processes in commercial carbon dioxide capture applications. The KYZC10 adsorbent's stable performance at varying temperatures contributes to its enhanced economic feasibility. This study also used the ideal adsorbed solution theory (IAST) to predict CO2 selectivity over other gases (CH4 and N2). [ABSTRACT FROM AUTHOR]

The ball bearing market is mature where there is a massive range of products available with new ones being developed all the time due to technological advancements. Additive Manufacturing (AM) provides a promising approach for developing oil-impregnated ball bearings. Oil impregnated bearings are critical for applications requiring smooth and low-friction motion. This study explores the feasibility of utilizing laser powder bed fusion (LPBF) technology to fabricate 304 stainless steel (304SS) samples with open pores, which can then be impregnated with a lubricant. To achieve this, 304SS powder was used, and optimum selective laser melting (SLM) printing parameters were altered to induce intentional pores. Initial screening of samples involved Archimedes density measurements and computed tomography (CT) scanning was conducted on a selected samples to assess their porosity levels. CT scan foam analysis results indicated a correlation between hatch spacing and porosity. Results revealed trends in cell volume and solidified scanning tracks thickness, indicating greater connectedness with larger pores. Synthesis of these findings could help in the development of efficient and reliable open pores that may find use in oil-impregnated self-lubricating ball bearings. [ABSTRACT FROM AUTHOR]

This study was aimed to determine the effects of various fruit juices used as impregnation solutions on the physicochemical, textural and sensory properties of dried chicken meat cubes. The pH, color parameters, total phenolic, antioxidant activity, water holding capacity, textural (TPA) and sensorial properties of the cubes were tested. Impregnation solutions used in the treatment groups were prepared with pomegranate, black grape and black mulberry juices, and salt solution (control). Impregnation was performed in two replicates and two samples were analyzed per replicate. The cubes were immersed in the solutions and the 10 min vacuum (250 mbar absolute pressure) − 10 min atmospheric pressure cycle was repeated at 4 °C for 2 h. pH values decreased (P < 0.01) by impregnation with various anthocyanin-rich fruit juices. Total phenolic and antioxidant activity were the highest (P < 0.01) in samples impregnated with pomegranate juice and were 720.71 mg GAE/kg and 840.22 mg TE/kg, respectively. The use of anthocyanin-rich fruit juices as impregnation solution decreased a* and b* values of samples (P < 0.01; P < 0.05, respectively). The TPA results indicated that impregnation with pomegranate, black grape and black mulberry juices induced lower (P < 0.01) hardness and higher (P < 0.05) adhesiveness values compared to the control. Consequently, the impregnation with anthocyanin-rich fruit juices such as pomegranate, black grape and black mulberry has the potential to improve the quality properties of dried chicken cubes. [ABSTRACT FROM AUTHOR]

This study aimed to assess the applicability of the extract and hydrosol obtained from the yarrow (Achillea millefolium) plant, which has grown widely in places where the Mediterranean climate prevails, as an impregnation agent for wooden materials. Red pine (Pinus brutia), oriental beech (Fagus orientalis), and walnut (Juglans regia) were selected as test samples of wood. An immersion method was used for the impregnation process that was performed for different time periods, 30 min (short), 3 h, (medium), and 24 h (long). Following the impregnation process, test samples were soaked in water for 6, 24, 48, 72, and 96 h to determine some physical properties of wooden material (retention, specific gravity, shrinkage, swelling, and water uptake). The results revealed that the highest retention after yarrow extract impregnation was achieved with red pine at 10% hydrosol concentration (2.29%) in a 30 min period whereas the lowest retention was observed with walnut material at 10% hydrosol concentration (1.17%) within a 24 h period. Yarrow extract did not have a significant effect on the physical properties of impregnated wooden materials; however, it was argued that the hydrosol was effective in the dimensional stability of all test samples due to its water-repellent properties.

This study evaluated the effects of microwave irradiation on the impregnation efficiency of zinc onto pulverized shrimp shell waste. Prior to impregnation, the pulverized shrimp shell was heat treated at 350, 450, and 550 oC for 1, 2 and 3 hours. After each treatment, the treated pulverized shrimp shell was immediately quenched in liquid nitrogen. Microwave-assisted impregnations were carried out at 80 oC for 10, 20, and 30 minutes and at 50% and 100% of the maximum delivery power rate of the laboratory microwave equipment. The resulting impregnated solids were characterized via TGA, DTA, FTIR, SEM, and XRD. Semi-quantitative measurement of the impregnated zinc was determined based on XRF analysis. The BET analysis of the original pulverized shrimp shell waste provided a surface area of 1.273 m2/g and achieved 30.423 m2/g after 550 oC for 3h heating treatment. An increase in crystallinity index was detected as the pulverized shrimp shell waste was exposed to higher and prolonged heating temperatures. Statistical analysis showed no significant difference (p = 0.05) in impregnated zinc levels among the heat-treated pulverized shrimp shells for the same power output of microwave energy. However, a significant difference was obtained between 50% and 100% power output, of which the latter can impregnate two-fold higher levels of zinc than the former. The results of this study concluded that the microwave-assisted technique might potentially be applied for metal impregnation for the preparation of heterogeneous catalysts, and the power strength of the microwave plays a prominent role in metal impregnation.

This study aimed to prepare ceramic membranes from low-cost materials for oil/water separation. TiO2 was incorporated into fly ash/kaolin-based ceramic membrane matrix via the impregnation method to enhance membrane performance. The scanning electron microscope (SEM) results exhibited random distribution of pores along the membrane surface with an estimated pore size of 0.001- 0.13 µm. The porosity of the TiO2-incorporated fly ash/kaolin ceramic membrane ranged from 42.82%-50.22%, where the sintering temperature played an important role in the water absorption and porosity properties. The X-ray diffraction (XRD) pattern showed an orthorhombic kyanite phase with the presence of three characteristic peaks at of 26.30°: 27.87° and 35.90°. The XRD pattern of all formulated membranes showed almost no change, however, the crystal intensity varied due to the different ceramic compositions. P hysicochemical properties evaluation showed that the membrane with fly ash, kaolin, and alumina of 20 : 30 : 40 wt% has reached the best characteristic. The casted membrane with a compaction pressure of 30 bar with sintering temperature of 1200oC for 7 h had the highest compressive strength. The performance showed that the TiO2 incorporated membrane achieved over 95% oil rejection efficiency and significant decrease of several parameters such as Pb, Fe, Mn, nitrate, nitrite, total dissolved solid (TDS), Cl and total organic matter without sacrificing the permeate water flux up to 116 L/m2/h. These experimental results suggest that the TiO2-incorporated Fly ash/kaolin ceramic membrane has great potential for reclaiming oily wastewater into clean water.

The behaviour of wood-metal composites was evaluated during cathodic dip coating, which is a standard corrosion protection process for metals in automotive engineering. In this process, the materials are exposed to chemical and thermal stresses, which is a challenge for wood and composites based thereon, especially in terms of the durability of the adhesive and the differences in thermal expansion. In this study, a hydrophobic surface sealant was proposed to mitigate these negative effects by reducing moisture absorption during dipping baths. The mechanical properties, including flexural strength, tensile strength and impact strength of aluminium-plywood composites were evaluated. It was found that impregnation with low-viscosity resins improved the mechanical properties by increasing the bulk density of the wood. Although the dip coating process reduced the strength of the impregnated samples, they maintained higher values compared to the non-impregnated samples. The dip coating process significantly reduced the tensile strength of the non-impregnated samples, while the impregnation protected the samples and maintained the tensile strength. It was concluded that hydrophobic surface sealing by impregnation is crucial for improving the mechanical properties of wood composites in automotive applications, as it reduces moisture absorption and maintains mechanical integrity during the dip coating process.

Abstract The ball bearing market is mature where there is a massive range of products available with new ones being developed all the time due to technological advancements. Additive Manufacturing (AM) provides a promising approach for developing oil-impregnated ball bearings. Oil impregnated bearings are critical for applications requiring smooth and low-friction motion. This study explores the feasibility of utilizing laser powder bed fusion (LPBF) technology to fabricate 304 stainless steel (304SS) samples with open pores, which can then be impregnated with a lubricant. To achieve this, 304SS powder was used, and optimum selective laser melting (SLM) printing parameters were altered to induce intentional pores. Initial screening of samples involved Archimedes density measurements and computed tomography (CT) scanning was conducted on a selected samples to assess their porosity levels. CT scan foam analysis results indicated a correlation between hatch spacing and porosity. Results revealed trends in cell volume and solidified scanning tracks thickness, indicating greater connectedness with larger pores. Synthesis of these findings could help in the development of efficient and reliable open pores that may find use in oil-impregnated self-lubricating ball bearings.

It is acknowledged that boron, ammonium, and nitrogenous compounds, which are used today as fire retardants, cause an increase in the hygroscopicity of wood materials. In this study, Scots pine (Pinus sylvestris L.), Anatolian chestnut (Castanea sativa Mill.), and Eastern spruce (Picea orientalis Link) woods were impregnated with 1.5% nano-sized hexagonal boron nitride (NB) according to ASTM D1413-76 (1976) standards. Flame-induced combustion (FIC), self-combustion (SC), and glowing combustion (GC) temperatures were determined. The highest retention amount was measured in spruce and the lowest was in chestnut among the wood samples taken for testing and measurement. When compared with the control samples, NB application caused an increase in SC and FIC temperatures (at higher rates). According to the glowing combustion temperature control samples, an increase was observed in chestnut and spruce and a decrease was observed in Scots pine among the samples applied with NB.

Metal and bi-metal catalysts supported by ZSM-5 zeolite (Mn/ZSM-5, Mn-Ag/ZSM-5, and Mn-Cu/ZSM-5 ) were synthesized using a simple impregnation method. Various analytical techniques, including XRD, SEM, and EDS, were employed to evaluate the crystal structure, morphology, and elemental distribution of the materials. Subsequently, different catalysts were used to evaluate the adsorption capacity of isopropanol (IPA) as well as the regeneration efficiency using ozone in-situ. With an initial concentration of isopropanol gas of 2000ppmv, 0.5 g of catalyst, and a flow rate of 100 mL/min, Mn − Ag bimetal-supported zeolite showed the highest notable efficiency of the adsorption process of 89.06mg/g. Furthermore, the manganese metal-supported zeolite preserved approximately 60% and 70% of its ozone regeneration capacity during several consecutive cycles with a 1 L/min ozone flowrate and 10 - and 60 -minute O3 treatments, respectively. Additionally, the catalyst can increase efficiency up to 80% after four cycles when the ozone flowrate is doubled in 10 minutes. This innovative adsorption-regeneration method of gas treatment can benefit the environment by minimizing energy consumption, reducing the need for high-temperature treatments, and lowering overall energy requirements, potentially influencing the future development of metal and bi-metal catalysts for treating various volatile organic compounds.