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Beta-amyloid (Aβ) peptide is one of the main characteristic biomarkers of Alzheimer's disease (AD). Previous clinical investigations have proposed that unusual concentrations of this biomarker in cerebrospinal fluid, blood, and brain tissue are closely associated with the AD progression. Therefore, the critical point of early diagnosis, prevention, and treatment of AD is to monitor the levels of Aβ. In view of the potential of metal-organic frameworks (MOFs) for diagnosing and treating the AD, much attention has been focused in recent years. This review discusses the latest advances in the applications of MOFs for the early diagnosis of AD via fluorescence and electrochemiluminescence (ECL) detection of AD biomarkers, fluorescence detection of the main metal ions in the brain (Zn

Janus structures have unique properties due to their distinct functionalities on opposing faces, but have yet to be realized with flowing liquids. We demonstrate such Janus liquids with a programmable distribution of nanoparticles (NPs) throughout their structures by joining two aqueous streams of NP dispersions in an apolar liquid. Using this anisotropic integration platform, different magnetic, conductive, or non-responsive NPs can be spatially confined to opposite sides of the original interface using magnetic graphene oxide (mGO)/GO, Ti3C2Tx/GO, or GO suspensions. The resultant Janus liquids can be used as templates for programmable, responsive, and mechanically robust aerogels suitable for piezoresistive sensing, human motion monitoring, and electromagnetic interference (EMI) shielding with a tuned absorption mechanism. The EMI shields outperform their current counterparts in terms of wave absorption, i.e., SET≈51 dB, SER≈0.4 dB, A = 0.91, due to their multi-scale porosity along with non-interfering magnetic and conductive networks imparted by the Janus architecture.

openaire: EC/H2020/788489/EU//BioELCell Funding Information: Dr. Arjmand would like to thank the Canada Research Chairs program for the financial support. The authors would like to acknowledge Syilx Okanagan First Nation for allowing us to conduct research in their unceded ancestorial traditional territory. Mr. Ahmadijokani, Dr. Kamkar, and Dr. Rojas are grateful for funding support from the Canada Excellence Research Chair Program (CERC-2018-00006) and the Canada Foundation for Innovation (Project number 38623). Dr. Rojas also acknowledges the European Research Council under the European Union's Horizon 2020 research and innovation program (ERC Advanced grant No. 788489, “BioElCell”). The authors also would like to thank Mr. Aydin Badrian (aydinbadrian.com) for his efforts on the graphical parts of this study. The appeal of metal–organic frameworks (MOFs) in wastewater treatment is tempered by their polycrystalline, powdery state, and challenges associated with their deployment. In the case of UiO-66, one of the most stable and widely-used MOFs, a low tendency for removing some organic contaminants has been observed on top of the mentioned issues. To address these challenges, herein, we take two complementary steps, i.e., hybridization of UiO-66 with organic nanodiamond (ND) followed by the integration of the hybrid nanoparticles in electrospun polymeric nanofibers based on chitosan/polyvinyl alcohol (PVA). We present the electrospinning of polymer/MOFs as a promising technique to fabricate highly efficient adsorbents for water remediation. We use the electrospun chitosan/PVA nanofibers (ECPN) as a versatile host for MOF nanoparticles that remove cationic methylene blue and anionic Congo red dyes. Four nanofiber composites containing thermally oxidized nanodiamond (TOND), ND, UiO-66, and TOND@UiO-66 are utilized tounravel the effect of nanoparticles type and loading on dye adsorption capacity. It is shown that incorporation of a small loading of nanoparticles in ECPN significantly enhaces the maximum dye adsorption capacity. More importantly, the rationally engineered hybrid TOND@UiO-66 nanoparticles exhibit the best performance in dye adsorption; for instance, an 80 % increase in maximum dye adsorption capacity, from 769 to 1429 mg/g, is recorded for ECPN loaded with TOND@UiO-66 compared to the unfilled ECPN. On top of that, the designed adsorbent showed appreciable regeneration ability after 6 adsorption–desorption cycles. All in all, this study offers a new generation of engineered advanced materials to remove emerging contaminants from water streams.

In this study, NH2-MIL-101(Al) metal-organic frameworks (MOFs) covered with 3-aminopropyltriethoxysilane (APTES) were incorporated into the polyethersulfone (PES) to produce mixed-matrix membranes (MMMs) for CO2 separation. The APTES functionalization was performed to improve the MOF dispersion in the PES matrix. Different analyses such as X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM) revealed that the MOFs surface successfully functionalized with APTES. An improvement in CO2/CH4 separation efficiency was observed in MMMs, and the performance shifted towards Robeson upper bounds. Notably, the membrane containing 10 wt.% S-MIL-5 (NH2-MIL-101(Al) functionalized with 5.0 mL of APTES) showed an increment in CO2 permeability (50%), and ideal CO2/CH4 selectivity (80%) compared to the PES membrane. The FTIR, TGA, FESEM, and DSC analyses constituted an excellent dispersion of MOFs within the PES phase, which led to significant development in gas permeability and selectivity.

To have a sustainable economy and environment, several countries have widely inclined to the utilization of non-fossil fuels like biomass fuels to produce heat and electricity. The advantage of employing biomass for combustion is emerging as a potential renewable energy, which is regarded as a cheap fuel. Chemical constituents or elements are essential properties in biomass applications, which would be costly and labor-intensive to experimentally estimate them. One of the criteria to evaluate the energy of biomass from an economic perspective is the higher heating value (HHV). In the present work, we have applied multilayer perceptron artificial neural network (MLP-ANN), least-squares support vector machine (LSSVM), ant colony-adaptive neuro-fuzzy inference system (ACO-ANFIS), particle swarm optimization- ANFIS (PSO-ANFIS), genetic algorithm-radial basis function (GA-RBF) and new multivariate nonlinear regression (MNR) as accurate correlation methods to estimate HHVs of biomass fuels based on the ultimate analysis. 535 experimental data were gathered from literature and categorized into eight classes of by-products of fruits, agri-wastes, wood chips/tree species, grasses/leaves/fibrous materials, other waste materials, briquettes/charcoals/pellets, cereal and Industrial wastes. In the term of statistical analysis, average absolute relative deviation (AARD) authenticates that MNR and GA-RBF algorithm with %AARD of 3.5 and 3.4 could be used to estimate HHV. In addition, developed models results were compared to the results of 69 recently previously published empirical correlations and it confirms the reliability of our results. Relevency factor shows the impact of biomass elements on HHV and outlier analysis indicates the unreliable experimental data. The results of this study can be used by researchers to design and optimize biomass combustion systems.

Funding Information: Dr. Arjmand would like to thank the Canada Research Chairs program for its financial support. The authors would like to acknowledge Syilx Okanagan First Nation for allowing to conduct research in their unceded ancestorial traditional territory. Mr. Ahmadijokani, Dr. Kamkar, and Dr. Rojas are grateful for funding support from the Canada Excellence Research Chair Program ( CERC-2018-00006 ) and the Canada Foundation for Innovation (Project number 38623). The authors also would like to thank Mr. Aydin Badrian (aydinbadrian.com) for his efforts on the graphical parts of this study. Publisher Copyright: © 2023 The Authors The exceptional structural stability of UiO-66 metal–organic framework (MOF) and ligands' functional groups render UiO-66 as a versatile candidate for multiple applications, including wastewater treatment. The possibility of a broad spectrum of post-synthetic modification of UiO-66 further expands its prospective uses. However, commercial applications of UiO-66 have been hindered by the polycrystalline nature of the powder. In this research, modification to obtain UiO-66-NH2 and post-processing with nanofibers comprising chitosan and polyvinyl alcohol (PVA) were applied to faciliate deployment as a suitable option for water decontamination. MOF nanoparticles were post-synthetically modified with 2,4,6-trichloro-1,3,5-triazine (TCT) and 5-phenyl-tetrazole (PT) to produce high-amine containing UiO-66, thus introducing active nitrogen-containing functional groups that enhanced the removal efficiency of targeted molecules from aqueous media. A systematic study was undertaken to optimize the supporting nanofibers and to demonstrate that even a low MOF functionalization, of up to 7- wt%, offered a maximum methyl orange adsorption capacity of 619 mg/g, superior to most adsorbents reported so far. Furthermore, selectivity, regeneration ability, and the effect of ambient conditions were demonstrated.

This article deals with the adsorption performances of the unmodified nanodiamond (ND) and thermally oxidized nanodiamond (Ox-ND) for the removal of different heavy metal ions such as Fe (III), Cu (II), Cr (VI), and Cd (II) from wastewater. The adsorption capacities of the ions onto adsorbents are higher and follow the order: Ox-ND-3 Ox-ND-1.5 ND, which is consistent with their surface areas, zeta potentials, and the presence of carboxyl groups, suggesting that electrostatic attractions between the positive metal ions and the negatively charged adsorbents are the predominant adsorption mechanisms. Adsorption capacities of these adsorbents were found to be 26.8, 31.3, and 45.7 mg/g for Fe (III), 25.2, 30.5, and 44.5 mg/g for Cu (II), 33.6, 44.1, and 55.9 mg/g for Cr (VI), and 40.9, 52.9, and 67.9 mg/g for Cd (II) over ND, Ox-ND-1.5, and Ox-ND-3, respectively. The impact of various operating parameters such as agitation time, initial metal ion concentration, temperature, pH solution, adsorbent dosage, and coexistence of the metal ions on the adsorption performance of Ox-ND-3 towards Cd (II) ions along with the batch adsorption experiments were performed. The equilibrium was reached in 120 min and adsorption data were fitted well with the pseudo-second-order kinetic as well as the Freundlich isotherm models. Adsorption process was spontaneous and exothermic, while the maximum removal efficiency of Cd (II) ions occurred at pH of 6.9 and at 4 g/L dosage. These findings demonstrated that thermally oxidized nanodiamond (Ox-ND) can be a versatile adsorbent to remove the Cd (II) ions from wastewater.

The phenolic-based brake friction composites containing 0, 1, 2 and 4 vol% carbon fiber were fabricated in this study. Thermogravimetric analysis (TGA) revealed the adverse impact of carbon fiber on the thermal stability of the composites under air atmosphere. Differential scanning calorimetry (DSC) of the uncured samples indicated the positive impact of carbon fiber on the crosslink density of the phenolic resin. Viscoelastic results drawn from the dynamic-mechanical analysis (DMA) suggested that inclusion of carbon fiber increased the storage modulus and decreased the damping factor of the frictional composites. The tribological behavior of the specimens was assessed with a chase type friction tester. Both the friction coefficient and specific wear rate decreased with enhancing carbon fiber content. Furthermore, carbon fiber deteriorated the fade behavior of the developed composites. The TGA, DSC and DMA results were used to justify and interpret the observed tribological behavior.

To investigate the effect of short carbon fibre on the tribological behavior of phenolic resin-based friction materials, a reference friction composite holding various ingredients without short carbon fibre, and three friction composites holding 1, 2 and 4 vol% carbon fibre were formulated. The dynamic-mechanical and thermogravimetric analyses showed the increase of storage modulus and reduction of thermal stability, respectively, with incorporation of carbon fibre into the brake composites. The tribological characterizations revealed that the coefficient of friction (COF) and specific wear rate of the friction composites dropped with addition of carbon fibre into the composites. Carbon fibre also aggravated the fade behavior, reduction of COF with temperature increase. The SEM imaging of the composites revealed the formation of primary and secondary plateaus in the friction composites after addition of carbon fibre. The results obtained from dynamic-mechanical analysis, thermogravimetric analysis and SEM imaging were employed to investigate the worn surface of the samples and justify the aforementioned tribological behavior.

Microwave regeneration of adsorbents offers several advantages over conventional regeneration methods; however, its application for microwave transparent adsorbents such as polymers is challenging. In this study, hypercrosslinked polymer/graphene oxide (GO) nanocomposites with large surface area and enhanced microwave absorption ability were synthesized. Polymers of 4, 4´-bis ((chloromethyl)-1, 1´-biphenyl- benzyl chloride) were hypercrosslinked through the Friedel-Crafts reactions. GO sheets were synthesized through the Hummer's method. Nanocomposites with different GO contents (1-8 wt%) were synthesized by solution mixing method. Thermogravimetry analysis revealed a large enhancement in the thermal stability of GO-filled nanocomposites compared to pristine polymer. N

International audience; The worldwide development of agriculture and industry has resulted in contamination of water bodies by pharmaceuticals, pesticides and other xenobiotics. Even at trace levels of few micrograms per liter in waters, these contaminants induce public health and environmental issues, thus calling for efficient removal methods such as adsorption. Recent adsorption techniques for wastewater treatment involve metal oxide compounds, e.g. Fe2O3, ZnO, Al2O3 and ZnOeMgO, and carbon-based materials such as graphene oxide, activated carbon, carbon nanotubes, and carbon/graphene quantum dots. Here, the small size of metal oxides and the presence various functional groups has allowed higher adsorption efficiencies. Moreover, carbon-based adsorbents exhibit unique properties such as high surface area, high porosity, easy functionalization, low price, and high surface reactivity. Here we review the cytotoxic effects of pharmaceutical drugs and pesticides in terms of human risk and ecotoxicology. We also present remediation techniques involving adsorption on metal oxides and carbon-based materials.

Metal-organic frameworks (MOFs) have recently achieved much attention to eliminating toxic pollutants because of their attractive attributes, including large specific surface area, ultra-high porosity, abundant active adsorption sites, tunable surface chemistry, well-controlled pore size distribution, and strong host-guest interactions. Among the many developed MOFs, the Zr-based MOFs, particularly the UiO-66 family, are considered extremely attractive for wastewater treatment applications. The fascinating properties of UiO-66 such as high thermal stability, superior chemical resistance towards several solvents, including benzene, acetone, different alcohols, dimethylformamide, acidic and basic solution, excellent chemical stability against various conditions such as air, water, and chloroform, and exceptional resistance to high external pressure, mainly due to strong Zr-O bond and high coordination number between the Zr clusters and organic ligands have led to numerous potential applications in wastewater treatment. This review primarily focuses on the latest efforts in applying UiO-66 MOFs as superior water-stable MOFs for efficient removal (adsorption/separation and degradation/reduction) of various water pollutants, including organic dyes, heavy metal ions, pharmaceuticals and personal care products, phosphate, and fluoride. The possible adsorption/separation and degradation/reduction mechanisms for removing water pollutants by UiO-66 and its modified derivatives are fully addressed. Thus, the review is expected to provide guidance and stimulate researchers to carefully investigate the real applications of UiO-66 MOFs in water and wastewater treatment applications.

In the present study, a magnetic core-shell metal-organic framework (Fe

Ethylenediamine-functionalized Zr-based metal-organic framework (MOF, UiO-66-EDA) was prepared via Michael addition reaction to investigate its potential for adsorption of heavy metal ions from water. Specifically, the influence of agitation time, solution pH, the dosage of the adsorbent, initial metal ion concentration, temperature, and coexistence of other metal ions was investigated on the removal efficiency of UiO-66-EDA towards Pb(II), Cd(II), and Cu(II) metal ions. The pseudo-second-order kinetic model governed the adsorption of these ions onto the UiO-66-EDA. Langmuir isotherm model matched the experimental isotherm of adsorption with a maximum adsorption capacity of 243.90, 217.39, and 208.33 mg/g for Pb, Cd, and Cu ions, respectively. The adsorption of Pb, Cd, and Cu ions onto UiO-66-EDA was dependent on electron exchange, electron sharing, electrostatic and covalent interactions between the metal ions as well as the abundant functional groups on UiO-66-EDA surface. Thermodynamic parameters such as free energy changes (ΔG), standard enthalpy changes (ΔH), and standard entropy changes (ΔS) were calculated, which revealed spontaneous and endothermic nature of the adsorption process. The UiO-66-EDA was stable and recyclable during adsorption studies of Pb, Cd, and Cu ions, suggesting its potentiality as an adsorbent for heavy metals recovery.

This work reports on the potential application of UiO-66 in gas sweetening and its structural stability against water, air, dimethylformamide (DMF), and chloroform. The UiO-66 nanoparticles were solvothermally synthesized at different scales and activated via solvent exchange technique using chloroform, methanol, and ethanol. Thus prepared and aged MOFs were characterized using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), and nitrogen adsorption-desorption analysis. The chloroform-activated MOF showed the largest surface area among all activation solvents, and presented high uptakes of 8.8 and 4.3 mmol/g for CO2 and CH4, respectively, at 298 K and 30 bar. This might be due to removing all unreacted organic ligands and DMF molecules from the pores of the framework. The UiO-66 nanoparticles are stable at the experimental conditions with no significant loss in crystalline structure and gas adsorption ability even after aging under different conditions for one year. The UiO-66 could be easily regenerated at 373 K with no observed significant reduction in gas uptakes even after five consecutive adsorption-desorption cycles. The present findings suggest the excellent potential of the UiO-66-derived MOFs as the promising materials for CO2/CH4 separation at low pressures and results can be applied in practical natural gas sweetening.

The fluoride ion is usually added to drinking water because of its prominent role in treating osteoporosis and improving dental health. However, fluoride contents over the optimal level (>1.5 ppm) in water resources has been found to have harmful effects on human health such as bone and dental fluorosis, Alzheimer's syndrome, DNA damage, infertility, kidney failure, acute gastric problems, thyroid disorder, brain damage, and even cancer. Therefore, sensitive and selective detection of fluoride ions and their removal from drinking water are of great significance. The unique features of metal–organic frameworks (MOFs), such as chemical activities, a broad range of functionalities, high stability, and modification opportunities for specific molecule detection or adsorption, make them broadly applicable in detecting and removing fluoride ions from water. The present review summarizes recent developments for detecting and removing fluoride ions from water by MOFs. The recent progress in fluoride removal via MOFs will be discussed in depth. The actual adsorption performance of various MOFs toward fluoride will be elaborated using partition coefficient (PC), independent of operating conditions. The detection and adsorption mechanisms are fleshed out comprehensively, providing insights and a roadmap to address current challenges and shed light on future study directions.

In the present study, a magnetic core-shell metal-organic framework (Fe3O4@PAA@UiO-66-NH2) nanocomposite was synthesized by a facile step-by-step self-assembly technique and used for selective adsorption of the anti-cancer Quercetin (QCT) drug. The synthesized nanocomposite was well characterized using FTIR, XRD, BET, FESEM, and TEM techniques. The adsorption kinetics and isotherms of the magnetic nanocomposites for QCT were investigated in detail at different initial concentrations and temperatures. It was found that the experimental adsorption kinetic and isotherm data were precisely explained by the pseudo-second-order kinetic and Langmuir isotherm models. Moreover, the selective adsorption ability of the synthesized nanocomposite against various drugs in the single, binary, and ternary solutions containing QCT, Curcumin (CUR), and Methotrexate (MTX) drugs was also studied. The synthesized adsorbent showed good adsorption selectivity for QCT against CUR and MTX. The adsorption mechanism of QCT on the nanocomposite might be related to the hydrogen bonding and hydrophobic-hydrophobic interactions via π-π stacking interactions between the benzene ring skeleton of QCT and the aromatic structure of the adsorbent nanoparticles. The regeneration and reusability studies demonstrated that the developed adsorbent sustained good structural stability and adequate adsorption capacity for QCT after ten consecutive adsorption-desorption cycles.

Mixed-matrix membranes (MMMs) are promising candidates for carbon dioxide separation. However, their application is limited due to improper dispersion of fillers within the polymer matrix, poor interaction of fillers with polymer chains, and formation of defects and micro-voids at the interface of both phases, which all result in the decline of the gas separation performance of MMMs. In this work, we present a new method to overcome these challenges. To this end, a series of MMMs based on polyethersulfone (PES) as the continuous polymer matrix and MIL-53-derived MOFs as the dispersed filler were prepared. FTIR-ATR, XRD, TGA, FESEM, and N2 adsorption/desorption analyses were employed to characterize the structural properties of the synthesized nanoparticles. The obtained results indicated that 3-aminopropyltriethoxysilane (APTES) molecules were successfully attached onto the surface of NH2-MIL-53(Al). Morphological characterization by FESEM and energy dispersive X-ray mapping (EDX) showed that desirable distribution within the whole membrane thickness, suitable nanoscale dispersion, and excellent interface were achieved by using amino-silane-grafted NH2-MIL-53(Al) (A-MIL-53(Al)) nanoparticles. The permeation results indicated that the permeability of two gases and the ideal CO2/CH4 selectivity enhanced by increasing the concentration of MOFs. In particular, comparing the experimental gas separation results of A-MMM-10 with those of pure PES membrane showed an 84% increase in the CO2 permeability and a 70% increase in CO2/CH4 selectivity. These results suggest that post-synthetic modification of MOF nanoparticles and strong interfacial adhesion between functionalized nanoparticles and polymer matrix could be a useful method to eliminate interfacial voids and improve gas separation efficiency.

In this study, a novel inorganic/organic hybrid pigment based on zinc cations/Ferula Asafoetida leaves extract (Zn-FALE) was synthesized, and its corrosion protection properties were investigated in a saline solution and an organic coating. Interactions of components between Zn2+ cations and FALE were assessed by thermo-gravimetric analysis (TGA) and ultraviolet-visible (UV–visible) spectroscopy. Corrosion inhibitive performance of FALE and Zn-FALE pigments in the solution phase and coating phase was studied using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). TGA and UV–visible results revealed the proper chelation between inorganic and organic components of Zn-FALE hybrid green pigments. Electrochemical measurement results showed that the addition of 200 mg L−1 FALE and Zn-FALE in the saline solution increased the total impedance of mild steel plates from ~672 to ~8154 and 12,786 Ω cm2, respectively, after 24 h immersion. Also, FALE and Zn-FALE showed a mixed-type inhibition mechanism with an efficiency of 67 and 90.2%, respectively. Moreover, EIS results in the coating phase showed that in the presence of 3 wt% of Zn-FALE pigments, the barrier and active corrosion protection performance of epoxy coatings enhanced significantly. The results showed that Zn-FALE pigments have a better performance compared to other extracts reported in the literature.

Human society is becoming more intransigent on removing organic dyes from polluted water before discharging to the environment. To fulfill this goal, a magnetic metal-organic framework adsorbent based on functionalized magnetic Fe3O4 nanoparticles and highly water stable UiO-66 with high porosity and sensitivity to the external magnetic field was designed and synthesized via an easy step-by-step self-assembly technique. The synthesized adsorbent magnetic nanoparticles (Fe3O4@UiO-66) were applied to remove organic dyes, i.e., methyl orange (MO) and methylene blue (MB), from a contaminated aqueous solution. The experiments displayed that magnetic Fe3O4@UiO-66 has good adsorption uptake for MO (244 mg/g) and MB (205 mg/g). The influence of several factors, including contact time, dye concentration, initial solution pH, the temperature of adsorption, and salt concentration, on the adsorption capacities of these dyes was assessed. The adsorption kinetic investigation demonstrated that the experimental adsorption data for both dyes well fitted the pseudo-second-order model. The thermodynamic research illustrated that the adsorption of both cationic and anionic organic dyes onto Fe3O4@UiO-66 was a thermodynamically spontaneous and endothermic process, and thermodynamically derived by entropy change rather than an enthalpy impact. Accordingly, the maximum adsorption capacities of Fe3O4@UiO-66 for MO increased from 243.9 to 303.0 mg/g with increasing the adsorption temperature from 25 to 45 °C. The excellent adsorption capacity, good water stability, excellent adsorption selectivity, proper regeneration, as well as good behavior in magnetic separation endorsed that the magnetic Fe3O4@UiO-66 could be a suitable adsorbent for dye elimination from aqueous solutions.

The Zr-based metal-organic framework (MOF, UiO-66) was synthesized solvothermally. The synthesized UiO-66 was activated using different solvents (acetone, chloroform, and ethanol) via two activation methods of centrifugation and Soxhlet extraction over different periods (1–10 days). The crystalline structure and morphology of the synthesized UiO-66s were characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, and field-emission scanning electron microscopy (FESEM) techniques. The adsorption behaviors of the synthesized UiO-66s were then investigated by selecting anionic methyl red (MR) and cationic methylene blue (MB) as the model dyes. It was found that a change in activation solvent and activation method would alter the physical properties of UiO-66, such as surface area, pore-volume, pore diameter, and surface charge. Experimental adsorption tests demonstrated that UiO-66 activated by ethanol via the Soxhlet extraction method for five days (abbreviated as ES-5) presented higher MR uptake capacity (243 mg/g) than the other synthesized UiO-66s, ascribed to its large surface area and total pore volume. Furthermore, it was found that the uptake capacity of ES-5 for cationic MB and anionic MR dyes increased and decreased, respectively, with raising the solution pH. This resulted in superior adsorption selectivity of MB over MR at pH 9.1. All in all, the findings of this work showed that the Soxhlet extraction method holds great promise for the activation of different MOFs.

A series of metal-organic frameworks (MOFs) based on aluminum-benzene dicarboxylates (MIL-53, NH2-MIL-53, and NH2-MIL-101) at different ratios have been synthesized, and their adsorption performances for methotrexate (MTX), an anti-cancer drug, have been investigated in terms of adsorption kinetics, isotherms, solution pH, thermodynamics, mechanism, and recyclability. Maximum adsorption values of 374.97, 387.82, and 457.69 mg/g were observed for MIL-53, NH2-MIL-53, and NH2-MIL-101 , respectively. Our study shows that adsorption capacity of MTX depends not only on surface area and pore volume but also on the zeta potential and the presence of suitable functional groups. Higher adsorption of NH2-MIL-101 observed for MTX than the other synthesized MOFs may be attributed to its large surface area, large total pore volume, high positive zeta potential, and polar amino functional groups located on its surface, which are responsible for its increased interactions with MTX molecules. Adsorption isotherms and kinetics of MTX onto NH2-MIL-101 followed the Langmuir and pseudo-second-order kinetic equations. Thermodynamic data suggest that adsorption of MTX onto NH2-MIL-101 is spontaneous and exothermic, while the adsorption mechanism is governed by electrostatic interactions, π-π stacking interactions, and H-bonding. Regeneration and recyclability of NH2-MIL-101 were also investigated by washing with ethanol to observe its decreased adsorption performance towards MTX. It was slightly decreased after seven adsorption-desorption cycles, indicating excellent regeneration and good structural stability under the chosen experimental conditions.

The presence of dyes as pollutants in wastewater sources from textile industries can cause significant health issues if they are not adequately treated. Dye adsorption to entrap contaminants in nanoparticle pores has created considerable attention in recent years due to the environmental concerns occurring as a result of spillage of dyes in water bodies. In efforts to understand adsorption capability UiO-66, metal-organic frameworks (MOFs) were developed and examined for the separation of four pollutant dyes containing methyl red (MR), methyl orange (MO), malachite green (MG), and methylene blue (MB), which are widely used in textile industries. The adsorbent structural stability in water, chloroform, and dimethylformamide (DMF) was studied for one year period to understand their chemical stability. The UiO-66 crystalline structure remained unchanged in water and chloroform, while XRD patterns of UiO-66 aged in DMF showed only a minor change, which might be due to the partially exterior framework collapse. The maximum adsorption capacities of pristine UiO-66 for anionic methyl red (MR) (384 mg/g) and methyl orange (MO) (454 mg/g) dyes were slightly higher than those of the cationic malachite green (MG) (133 mg/g) and methylene blue (MB) (370 mg/g) dyes, particularly at lower pH values. The partition coefficients of pristine UiO-66 for MR, MO, MG, and MB dyes were found to be 1.137, 2.208, 0.070, and 1.345 mg/g µM, respectively, which indicated that pristine UiO-66 had a good affinity to MO dye. The adsorption results perfectly matched the pseudo-second-order kinetic model. The MR, MO, and MB adsorption isotherms have matched the Langmuir model, while MG isotherms are in line with the Freundlich model. The distinctive features of the UiO-66 framework make it potentially applicable for the treatment of wastewater.

The present investigation aims to explore the influence of simultaneous loading of aramid/carbon fibers, as high-performance reinforcements, on thermal, mechanical, and frictional behaviors of phenolic-resin-based non-asbestos organic (NAO) friction materials. The hybrid composite specimens were made at different ratios of carbon and aramid fibers but at a total fixed fiber loading of 8 vol%. The influence of carbon fiber on the improvement of impact strength and thermal conductivity was found to be more prominent than aramid fiber. The thermal stability of friction composites under nitrogen and real condition was investigated. The frictional data drawn from a Chase type friction tester revealed that the coefficient of friction and fade behavior were improved by incorporating aramid fiber. However, carbon fiber improved the wear resistance significantly in comparison with aramid fiber. The surface morphology of the composites was investigated precisely using scanning electron microscopy. Taking all the characterizations (physical, thermal, and tribological) into account, it was revealed that the sample holding 6 vol% aramid fiber and 2 vol% carbon fiber presented the best performance in terms of coefficient of friction, wear rate and fade behavior.

Reinforcement of rubbery materials with carbon nanotube (CNT) has gained much attention over the last few decades due to the inherent ability of CNT to improve the physical and mechanical properties of polymer composites. However, CNT renders electrical conductivity to the rubber composites, which could be problematic for a number of applications. In an attempt to overcome such issues, we controlled the insulating properties of styrene-butadiene rubber (SBR) nanocomposites by hybridization of CNT with nanodiamond (ND) particles without scarifying desirable features of the nanoparticles. In this respect, the effects of carbon nanotube (CNT) and nanodiamond (ND), either individually or in hybrid form, on mechanical, physical, morphological and thermal properties of styrene-butadiene rubber (SBR) nanocomposites were well characterized in the present research using bound rubber, tensile, dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), electrical, and thermal conductivity characterizations. The SBR nanocomposites holding nanoparticle concentrations ranging from 1 to 5 phr were fabricated at various CNT/ND compositions. The results indicated that the hybridization of nanoparticles improved the dispersion state of individual nanoparticles in SBR, successfully controlled the insulating behavior of the SBR nanocomposite and enhanced the thermal conductivity of SBR in synergistic manner; while the mechanical improvement retained as CNT filled SBR. The SBR nanocomposites holding 5 phr hybrid-nanoparticles with appropriate nanoparticles composition possessed thermal conductivity more than two-fold of unfilled SBR and 20% more than nanocomposite with 5 phr loading of single CNT.