Unmodified Samples Research Articles

Interphase mechanics vs chemical compatibility: Generating a deformable PA6-carbon fiber interphase

Good interfacial adhesion is typically correlated to obtaining the best tensile/flexural performance for carbon fibre-reinforced composites. The nature or even presence of the interphase, a localized region around the fibre-matrix junction, is often discussed but notoriously difficult to visualize and characterise. Here, a surface-initiated electro-polymerization approach to covalently graft either polyacrylamide or polygylcidyl methacrylate to the carbon fibres was used. This was followed by continuous melt compounding into the polyamide-6 matrix prior to injection moulding. Analysis via X-ray photoelectron spectroscopy (XPS) coupled with topological/visual study through scanning electron microscopy (SEM), showed distinct surface changes after modification and at the composite fracture surface. Additionally, mechanical (tensile, flexural, and tribological characteristics) and thermal (differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA)) investigations were performed. The results showed that the unmodified CF samples exhibit higher tensile and flexural modulus than the modified CF samples. However, the wear rate has been significantly decreased for modified CF samples. SEM of fractured composite surfaces showcased a clear interphase region surrounding the fibre, highlighting the importance of interphase/interphase mechanics in the design of optimal composite interfaces.

Developing an efficient anticorrosive system through advanced modification of plasma-electrolyzed MgO with CeNiLDH complexed with V₂O₅ nanoparticles and (2E)-But-2-enedioic acid

Advanced hybrid materials with unique properties are essential for addressing the demands of increasingly complex applications. Despite their importance, the self-assembly of layered double hydroxides (LDH) with metallic oxide nanoparticles and dicarboxylic acids is constrained by a limited understanding of the formation mechanisms and difficulties in evaluating their anticorrosive performance. In this study, we developed a novel anticorrosive system by intercalating CeNiLDH with a complex of vanadium pentoxide (V₂O₅) nanoparticles and (2E)‑but-2-enedioic acid ((2E)-BDA) on a MgO layer created through plasma-electrolysis of AZ31 Mg alloy. This system was compared with LDH films intercalated with either V₂O₅ or (2E)-BDA alone. The intercalation of LDH with V₂O₅ and (2E)-BDA resulted in a flower-like structure, while modification with their complex led to a more compact, cloud-like formation. These cloud-like structures, driven by enhanced absorption and robust hydrogen bonding throughout the hierarchical network, effectively suppress corrosion by delaying the movement of corrosive anions. This was reflected in a polarization resistance of 1.51 × 10¹⁰ Ω·cm², which is approximately two orders of magnitude times higher than the resistance of the unmodified LDH film (3.41 × 10⁸ Ω·cm²). Additionally, the corrosion current density (icorr) of the VOBDA sample showed a decrease by four orders of magnitude compared to the unmodified LDH sample, emphasizing the superior anticorrosive performance of this hybrid coating. Density functional theory (DFT) was used to elucidate the bonding and formation mechanisms between LDH and the inorganic-organic complex.

Development of Technologies for Processing Polypropylene Foil Waste and Their Use in the Production of Finished Products

This work aims to assess the possibility of using packaging industry waste to modify polypropylene products (PPs). The products were made in the form of extruded foil and injected samples. The products were produced using regranulate made of polypropylene cast foil. Maleic anhydride-modified polypropylene (MAPP) and polyolefin elastomer (POE) with a glycidyl ester functional group were used to modify the polypropylene. The samples were produced based on 50% foil waste reground and 50% pure PP. The rheological properties of the blends were assessed using the melt mass flow rate (MFR) technique; thermal properties using the differential scanning calorimetry method (DSC). The products manufactured using the injection molding method were subjected to an analysis of mechanical properties, such as tensile strength and impact strength. Also, in the case of film samples, tensile strength was assessed. Color-change assessments with CIE L*a*b* were carried out for all materials. Injection-molded products based on recycled metallized cast foil showed favorable mechanical properties such as tensile strength (1 MAPP = 26.7 MPa; 2 MAPP = 27.1 MPa), which was higher than the original material (cPP = 20.7 MPa). Also, for the films produced from regrind, the tensile strength was at a level similar (1 MAPP = 24.6 MPa; 2 MAPP/POE = 25.1 MPa) to the films extruded from virgin materials (cPP = 24.9 MPa). The introduction of a POE additive to the blends resulted in increased impact strength (1 MAPP/POE = 31 kJ/mol; 2MAPP/POE = 18 kJ/mol; 3 MAPP/POE = 11 kJ/mol) in relation to unmodified samples (cPP = 7 kJ/mol). The introduction of a POE additive to the tested mixtures improved the impact strength of the injected products by almost 4 times for sample 1 MAPP/POE and 2.5 times for sample 2 MAPP/POE in comparison to virgin cPP. These studies confirmed that foil waste can be successfully used to modify polypropylene products shaped both in the injection and extrusion processes.

Oxygen vacancy induced defect dipoles in BiVO4 for photoelectrocatalytic partial oxidation of methane

A strong driving force for charge separation and transfer in semiconductors is essential for designing effective photoelectrodes for solar energy conversion. While defect engineering and polarization alignment can enhance this process, their potential interference within a photoelectrode remains unclear. Here we show that oxygen vacancies in bismuth vanadate (BiVO4) can create defect dipoles due to a disruption of symmetry. The modified photoelectrodes exhibit a strong correlation between charge separation and transfer capability and external electrical poling, which is not seen in unmodified samples. Applying poling at −150 Volt boosts charge separation and transfer efficiency to over 90%. A photocurrent density of 6.3 mA cm−2 is achieved on the photoelectrode after loading with a nickel-iron oxide-based cocatalyst. Furthermore, using generated holes for methane partial oxidation can produce methanol with a Faradaic efficiency of approximately 6%. These findings provide valuable insights into the photoelectrocatalytic conversion of greenhouse gases into valuable chemical products.

Glass fiber waste as a potential bitumen modifier and stabilizing agent in asphalt mixture.

The deterioration of Malaysia's flexible road pavements due to rutting and moisture damage presents a critical problem. Meanwhile, disposing of glass fiber wastes from manufacturing process further worsens environmental concerns. This research explores the feasibility of using glass fiber wastes as bitumen modifiers and stabilizers in stone mastic asphalt (SMA). The performance of SMA14 incorporating glass fiber waste using wet method and dry method were compared in this study. Bitumen 60/70 PEN was modified with varying percentages of glass fiber waste namely, 0.5%, 1.0%, 1.5%, and 2.0% by weight of bitumen. The SMA14 mixture was modified with glass fiber waste at 0.3% by the weight of total mixture. The physical and rheological characteristic of modified bitumen binder were assessed using penetration, softening point, storage stability, viscosity, and dynamic shear rheometer (DSR) tests. The Marshall properties and performance of the SMA14 mixture incorporating glass fiber waste were evaluated. The findings demonstrate that glass fiber waste-modified bitumen exhibits enhanced penetration, softening point, viscosity, and rutting resistance compared to the unmodified sample. Adding glass fiber waste using dry method shows significant resistance to abrasion and rutting and demonstrates higher indirect tensile strength and TSR value.

Surface treatment effects on morphological and property enhancements of poly (3‐hydroxybutyrate‐co‐3‐hydroxyvalerate)/Diss fibers (Ampelodesmos mauritanicus) biocomposites

AbstractThe present research investigates the influence of chemical modifications on the surface of Diss fibers (Ampelodesmos mauritanicus) as an effective reinforcing agent for biocomposites based on poly (3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV). The Diss fiber surface underwent three different chemical treatments: alkaline, alkaline/peroxide, and alkaline/silane. Changes in morphology, mechanical properties, thermomechanical behavior, and contact angle measurements of the biocomposite materials were studied according to the following weight ratio PHBV/Diss fibers 80/20. Scanning electron microscopy (SEM) analysis of the fractured surface of the biocomposite samples revealed improved adhesion between Diss fibers and the PHBV matrix after surface modification, compared with the unmodified sample. The study demonstrated that the incorporation of Diss fibers leads to an enhancement in the mechanical performances of PHBV‐based biocomposites. The tensile properties of the modified biocomposites showed a significant increase in Young's modulus compared with the biocomposites with untreated fiber. Similar trends were observed in the data obtained from dynamic mechanical analysis (DMA) and contact angle measurement. Overall, the study highlights the beneficial effects of Diss fibers modification, particularly with the alkali–silane combination, in enhancing the properties of PHBV biocomposites, there by broadening their potential application fields.Highlights The study explores the potential of Diss fibers as an effective reinforcement for PHBV‐based biocomposites. Fully biodegradable biocomposites based on PHBV/Diss fibers are melt‐compounded. Diss fibers are chemically modified by alkaline, alkaline/peroxide, and alkaline/silane. The chemical treatment has considerably enhanced the properties and morphology of the biocomposites, being however much higher for alkaline/silane treatment. The method can be used for specific applications and large‐scale production.

Enhancing Fire Resistance of Geopolymers Modified with Thermal Insulation Additives

This study aims to improve the fire resistance of geopolymers by adding thermal insulation materials. These additives help the material perform better at high temperatures. Previous research focused on using fly ash, metakaolin, and zeolite in geopolymer composites. This study looks at how porous additives affect compressive strength and whether non-destructive testing can measure damage after heat exposure. Four temperature tests were set: 400 °C for 60 min, 400 °C for 120 min, 800 °C for 60 min, and a maximum of 658 °C for 120 min. The results showed that the compressive strength and ultrasonic pulse velocity (UPV) dropped as the temperature increased, with a sharp decrease at 800 °C. Unmodified samples broke apart at high temperatures, while modified samples lost 40% to 70% of their strength. The study confirmed that a dense, amorphous matrix improves heat resistance, even with porous additives like fly ash. A link between UPV and compressive strength was found, suggesting non-destructive testing could be useful for checking structural integrity after a fire.

Aerated Concrete, Based on the Ash of Thermal Power Plants, Nanostructured with Water-Soluble Fullerenols

This study is devoted to the synthesis of aerated concrete by a non-autoclave method using ash from thermal power plants and a nanopreparation. Fullerenol-m was used as a nanopreparation. The fullerenol-m content in the sealing water of aerated concrete changed in the range of 0.00 ÷ 0.03 mas.%. The main performance characteristics of the nanostructured aerated concrete were studied, namely the compressive strength, impact toughness, thermal conductivity, density and moisture content. A significant improvement in the performance characteristics of the nanomodified aerated concrete compared to unmodified samples was demonstrated, which was most clearly manifested as an increase in impact toughness by several (three to five) times. The best performance characteristics of the modified aerated concrete were observed at a fullerenol-m concentration relative to the added cement within 0.022–0.028 wt.%. The authors attribute such a strong change and improvement in the physical, chemical and operational properties of aerated concrete when modified with fullerenol-m to the fact that fullerenol-m (a few thousandths of wt.%) has a very strong structuring effect on the sealing water and, as a consequence, on the resulting aerated concrete.

Optimizing the radiation synthesis and swelling of agar-based acrylate superabsorbent hydrogel for irrigation water conservation

This study reports the synthesis of novel agar/poly methacrylic acid/poly acrylic acid (AG/PMAc/PAc) superabsorbent hydrogels via gamma radiation and their subsequent urea modification to enhance swelling and water retention for agricultural applications. The superabsorbent hydrogels were prepared by irradiating aqueous mixtures of varying agar concentrations with methacrylic acid/acrylic acid (MAc/Ac) monomers, followed by urea treatment at different cycles and concentrations. The morphological characteristics and chemical structures were confirmed by SEM and FTIR, respectively. The maximum swelling occurred at 6 % agar and 1 % urea modification. Remarkably, the 1 % urea-modified hydrogel displayed a 41.1 % swelling increase and 236.4 % enhancement after the second modification cycle compared to unmodified samples. Water retention studies showed the modified hydrogel retained 53.2 % moisture after 14 days versus the complete drying of unmodified hydrogels. Soil application studies demonstrated the modified hydrogel increased moisture content by 177.3 % after 20 days, promoting better growth with 30 % more leaves and 38.9 % higher stem length in Vicia faba plants versus controls. This novel radiation-synthesized, urea-modified hydrogel with exceptional swelling and moisture retention capabilities shows promising potential for sustainable agricultural irrigation and crop productivity enhancement under water-deficit conditions.

Antimicrobial activities of modified and unmodified pectin obtained from peels of Irvingia gabonensis, Cola milleni, and Theobroma cacao on specific pathogenic organisms

The antibacterial and antifungal activities of ethanolic extracts of pectin derived from the peels of Theobroma cacao, Cola milleni, and Irvingia gabonensis were investigated against phytopathogenic bacteria and fungi. The agar diffusion method was employed to test the extracts against Staphylococus aureus, Pseudomonas aeroginosa, Chromobacterium violaceum, Streptococcus feacalis, Xanthomonas axonopodis, Erwinia carotovora, Sclerotium rulfsii, Pythophthora palmivora, and Pyricularia oryzae. Significant differences (p<0.05) were observed in all control groups. The extracts inoculated with Streptomycin exhibited the highest activity against all bacterial strains. Conversely, the unmodified extracts of pectin samples from cola, cocoa, and wild mango displayed the least inhibitory activity against the tested bacterial strains, while the modified extracts with Chloro Acetic Acid (CAA), Para Amino Benzoic Acid (PABA), and Para Nitro Benzoic Acid (PNBA) showed varying inhibitory effects. The control sample inoculated with Mancozeb demonstrated the highest zone of inhibition against all fungal strains in the three pectin samples. However, the modified pectin samples exhibited increased inhibitory effects compared to the unmodified pectin extract, although the results were closer to the control. The higher values of modified pectin can be attributed to the presence of modifying agents such as long-chain hydrocarbons, acetic acid, chloro compounds, carboxyl, benzene rings, amino groups, and nitro groups. The presence of secondary metabolites in the pectin samples may also contribute to the higher values observed in both modified and unmodified samples. Overall, the results indicate the fungicidal and bactericidal potential of the extracts against the tested organisms, suggesting their potential use as broad-spectrum antimicrobial agents.

Composite photocatalysts g-C<SUB>3</SUB>N<SUB>4</SUB>/TiO<SUB>2</SUB> for hydrogen production and dye decomposition

The photocatalytic activity of the g-C3N4 /TiO2 composite samples in the processes of dye (methylene blue) decomposition and hydrogen evolution from an aqueous ethanol solution under the action of visible radiation (400 nm) has been studied. A new original method for the synthesis of the g-C3N4 /TiO2 composite by depositing g-C3N4 /TiO2 to TiO2 nanoparticles during sol-gel synthesis is proposed. The synthesized photocatalysts were characterized by X-ray diffraction, low-temperature gas adsorption, X-ray photoelectron spectroscopy, high-resolution transmission microscopy, and diffuse reflectance spectroscopy in the UV and visible regions. The maximum activity in the hydrogen evolution reaction was 1.3 mmol h–1, which exceeds the rate of hydrogen evolution on the unmodified g-C3N4 and TiO2 samples.

Effect of Electron Irradiation on the Optical Properties of Zinc Oxide Powder Modified by Magnesium Oxide Nanoparticles

The effect of modifying ZnO powders with MgO nanoparticles (with a concentration of 0.1–10 wt. %) on their diffuse reflectance spectra in the region of 0.2–2.5 μm before and after irradiation with 30 keV electrons was studied. Modification of ZnO powder was carried out by MgO nanopowder with concentrations from 0.1 to 10 wt. % using a solid-state method at 650°C heating temperature. X-ray diffraction analysis showed that this method of modification there is no formation of additional phases. It has been established that zinc oxide structure symmetry belongs to the P63mc space group, magnesium oxide – to the Fm–3m space group. The spectral reflectance of such powders in the visible region is over 90%. Under irradiating by 30 keV electrons of initial and modified ZnO powders, as well as MgO nanopowder, a decrease in their reflectance recorded in the entire studied region of the spectrum. It has been established that modification with MgO nanoparticles at a concentration of 3 wt. % leads to an increase in radiation resistance by a factor of 1.32 compared to unmodified samples. This effect is determined by the sink of radiation defects on the large specific surface area of nanoparticles.

Enhancing moisture-resistance in polyimide aerogels: A novel hydrophobic modification approach with ortho-positioned long-chain barriers

Polyimide (PI) aerogels possess significant potential for various applications due to their outstanding mechanics and thermal insulation. However, a major drawback of these aerogels is their susceptibility to moisture, which not only compromises their insulative performance but also leads to an increase in weight. To address this issue, we have developed a moisture-resistance technique by incorporating a long-chain hydrophobic barrier at the ortho position relative to the imide groups to enhance the moisture-resistance of the PI aerogels. This approach involved using a series of diamines with hydroxyl groups strategically located at the ortho position of imide groups as reactants. The resulting PI aerogels demonstrated a significant improvement in water resistance, reducing water-uptake to merely one-tenth of that recorded in unmodified samples. Furthermore, the effectiveness of this hydrophobic modification was validated through molecular dynamics simulations, which indicated a diffusion coefficient of 4.41 × 10−11 m2/s after modification. These findings represent a considerable advancement in developing effective methods for hydrophobic modification of PI aerogels, with potential applications in aerospace, electronic communications, and environmental protection.

The effect of the modification mechanism of SiO2 in resin‐based friction materials on the mechanical and tribological performance

AbstractThis study aimed to address the thermal degradation of resin‐based friction materials in the mid‐temperature stage (200–250°C), as well as the resulting instability of the friction coefficient and decrease in the mechanical properties. To investigate the impact on the toughening and wear resistance properties, this study employed nanosilica‐modified resin‐based friction materials. The mechanical, friction, and wear properties of the modified samples were tested using a Rockwell hardness tester, hydraulic universal testing machine, and constant speed friction tester. The phase composition and microstructure of the samples were analyzed by scanning electron microscope, energy‐dispersive x‐ray spectroscopy, x‐ray diffraction. When the mass fraction of nanosilica was 3%, modified sample S3 exhibited excellent mechanical properties, with shear strength and compressive strength reaching 40.3 and 171.7 MPa, respectively, which were increased by 30% and 9% compared to unmodified sample S1. Moreover, the density and hardness of sample S3 showed minimal variation compared to those of unmodified sample S1. In the temperature range of 100–250°C, the wear rate of modified sample S3 remained within the range of 0.22 × 10−7–0.38 × 10−7 N−1 m−1, with a friction coefficient of 0.38 at 200°C, demonstrating excellent wear resistance.

Layered Structure Modification of Sodium Vanadate through Ca/F Co‐Doping for Enhanced Energy Storage Performance

AbstractVanadate materials are promising for sodium‐ion batteries (SIBs) due to their low cost, high capacity, and high power characteristics enabled by vanadium's multiple oxidation states. However, their development is hindered by poor conductivity, suboptimal high‐rate performance, and limited cycle life. In this work, a layered structure modification strategy involving Ca/F co‐doping in sodium vanadate Na2CaV2O6F (CVF) is proposed to address these issues. Through a combination of experiments and density functional theory calculations, it is demonstrated that Ca/F synergies enhance the Na layer spacing in CVF, resulting in reduced crystal water content and volume shrinkage compared to Na2V2O6 (NVO). Additionally, Ca/F incorporation significantly mitigates the diffusion potential of Na+ within the material framework. The unmodified CVF sample exhibits a high reversible capacity of 220 mAh g−1 at 10 mA g−1 and an excellent rate capacity of 65.78 mAh g−1 at 400 mA g−1. Furthermore, the cathode material maintains a capacity of up to 138 mAh g−1 at 200 mA g−1 and retains 104.88 mAh g−1 after 100 cycles within the voltage range of 1.5−4.0 V. These findings enhance the understanding of the crystal structure of NVO cathode materials and pave the way for the rational design of high‐quality vanadate cathodes for SIBs.

Efficacy of silver nanoparticle-modified bullfrog skin as an antimicrobial wound dressing

This research explores the synthesis of silver nanoparticles and their incorporation into bullfrog skin for potential use as a wound dressing. The study addresses the need for wound dressings that exhibit biocompatibility, low cytotoxicity, superior biodegradability, and antimicrobial activity. Silver nanoparticles were synthesized using silver nitrate and sodium citrate solutions and integrated into bullfrog skin at varying concentrations (0%, 0.5%, 1%, and 1.5%). The modified and unmodified bullfrog skin samples were characterized using dynamic light scattering(DLS), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectroscopy (EDS). Antimicrobial analyses were conducted to assess the efficacy of the modified skin against common pathogens, including Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. The results demonstrated that samples containing 1% and 1.5% silver nanoparticles exhibited significant inhibitory effects on all tested microorganisms. This indicates that these concentrations are optimal for antimicrobial activity, suggesting the potential of silver nanoparticle-modified bullfrog skin as an innovative and effective wound dressing material.

Stabilization of Pb/Zn mine tailings by modified fly ash: characterization, performance, and mechanism.

The presence of heavy metals in mine tailings poses a serious threat to the surrounding environment. In this study, we aimed to stabilize Pb/Zn-containing mine tailings using modified fly ash (FA) with various alkali solutions. Notably, the modification of FA with Na2SiO3 (NaSi-FA) resulted in the most significant structure changes. To understand the adsorption mechanism of Pb and Zn by modified FA, batch adsorption experiments were conducted. Doubling the adsorption capacity for both Pb and Zn was observed in the modified FA samples compared to unmodified samples. These results could be attributed to the enhanced surface area and porous structure, providing more anchor sites for the heavy metal ions. Additionally, the adsorption of Pb and Zn was found to follow the Langmuir isotherm and pseudo-second order kinetic. Molecular dynamics simulations further supported the notion that Pb and Zn ions could effectively exchange with Na ions within the N-A-S-H gel network, ultimately solidifying them in its structure. Stabilizing Pb/Zn tailings with NaSi-FA resulted in a significant decrease in the leaching of Pb and Zn. Specifically, the leading amount decreased by 55.2% for Pb and 35.3% for Zn, showcasing the superior performance of this stabilization method. This reduction in leaching indicates effective compliance with environmental regulations regarding the containment of Pb and Zn.

Image Contrast and Spectral Transmission of Presbyopia-Correcting Intraocular Lenses: Evaluating the Impact of Nd:YAG Laser Associated Defects

Purpose Neodymium yttrium aluminum garnet (Nd:YAG) laser capsulotomy is considered gold standard in the treatment of posterior capsule opacification (PCO). In this laboratory study, we measured spectral transmission to evaluate the image contrast and analyze the impact of Nd:YAG associated defects in presbyopia-correcting intraocular lenses (IOLs). Methods Two hydrophobic, acrylic IOLs as classic multifocal lenses with diffractive ring segments and different amount of near addition (A, B), one hydrophilic, trifocal IOL (C), one sector-shaped, plate haptic IOL (D) and one hydrophobic, enhanced depth of focus (EDOF) IOL (E) were studied. Measurements included surface topography characterization, United States Air Force resolution test chart (USAF) analysis, spectral transmittance measurements and through focus contrast measurement. Measurements were done with unaltered samples, damages (n = 7) were intentionally created in the central 3.5 mm zone using a photodisruption laser (2.0 mJ) and measurements were repeated. Results Significant differences were shown between unmodified samples and samples with YAG pits. The YAG-pits decreased the image contrast and spectral transmission and changed results of USAF test images. The imaging contrast decreased to 66%, 64%, 60%, 52% and 59% with the YAG shots in samples (A-E). The light transmission decreased to 88%, 87%, 92%, 79% and 91% (A-E) on average between 400 nm to 800 nm. In all IOLs a reduction of the relative intensity of transmitted light was observed. Conclusion The image performance of all tested presbyopia-correcting IOLs is significantly influenced and disturbed by YAG-pits. The intensity of transmitted light is reduced in the wavelength between 450–800 nm. USAF test targets show worse results compared to unmodified samples and contrast is significantly deteriorated. No ranking/rating among tested IOLs should be made as many other factors play a role in real world scenario. High care should be taken when performing Nd:YAG capsulotomy on premium IOLs to avoid any damages.

In situ carbon nanonetwork structure based on MOF-derived carbon to manufacture ceramic composites: A case study of zirconia-toughened alumina

Highly robust ceramics materials are promising materials for applications in the automobile, aerospace, and ceramic cutting tool industries. However, conventional ceramics are typically brittle, which limits their suitability for advanced applications. In this study, with zeolite imidazolium salt skeleton-8 (ZIF-8) as a carbon source, discharge plasma sintering is used to create carbon nanonetworks derived from metal-organic frameworks (MOFs) in situ on the grain boundaries of zirconia-toughened alumina (ZTA) ceramic. ZTA exhibits maximum bending strength (719 ± 20.5 MPa) and fracture toughness (7.91 ± 0.7 MPa m1/2) at MOF concentrations of 1.0 wt% and 2.0 wt%, respectively, which are 1.37 and 1.88 times higher than that of the unmodified sample. This demonstrates that the MOF-derived carbon nanonetworks significantly improve the mechanical properties of the ceramic. The finite element analysis results indicate that the carbon nanonetworks can effectively disperse the stress inside the material and transfer the concentrated stress from the internal defects to the two-phase grain boundary on the surface of the sample, thereby contributing to strengthening and toughening. Overall, this work validates that the in situ production of carbon nanonetworks from MOFs is an effective strategy to enhance the mechanical properties of ZTA ceramics. Moreover, it offers new approaches for reinforcing and toughening other ceramic materials.

Basic and microwave modification processes to produce new activated carbon adsorbents based on Pistacia atlantica Kurdica nuts as carbonaceous raw material; A comparative study on the adsorption and elimination of acid blue 113

The nutshell of the pistachio tree was used as a precursor for producing new activated carbon (AC) adsorbent. The raw material was rinsed in H3PO4 (85 % w/w) and heated in a cylindrical furnace at 350 °C/90 min to 700 °C/60 min in a He and NH3 atmosphere. To change the surface chemistry, basic modification of AC was done under the NH3 atmosphere at 700 °C. The FT-IR spectrum showed apparent changes. The microwave, as second modification method, led to significant changes in the porosity properties of AC, especially in the surface area. The SEM images showed the differences in the morphology of the modified and unmodified samples. In the next step, an improved adsorption process was implemented to remove acid blue 113 (AB113). Basic and microwave-modified AC (BMM-AC) showed an enhanced removal efficiency of more than 97.54 % compared to AC, 60.32 %, microwave-modified AC (MM-AC), 73.08 %, and basic modified AC (BM-AC) 88.72 %, which revealed the positive role of the modification methods. Increasing the SBET from 238.8 to 368.6 m2/g using microwaves and changing the surface chemistry by basic modification were significant results of the study. These changes led to the construction of an improved removal process using BMM-AC to eliminate AB113.