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1.
Polymers (Basel) ; 16(9)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38732659

ABSTRACT

Nanoparticles of spinel ferrites with a composition of Co0.9Cu0.1Fe2O4 (AM NPs) were effectively synthesized via a hydrothermal route. The structure of ferrite nanoparticles was characterized with X-ray diffraction, which showed a single cubic spinel phase. Energy-dispersive X-ray (EDX) spectroscopy and field emission-scanning electron microscopy (FE-SEM) were employed to analyse elemental composition and surface morphology, respectively. Moreover, the effects of the Co0.9Cu0.1Fe2O4 on the morphology of [PLA = polylactic acid] nanocomposites were examined through polarized light optical microscopy (POM) and X-ray diffraction (XRD). The thermal behaviours for tested samples were studied through [DSC = differential scanning calorimetry] and [TGA = thermal gravimetric analysis]. A great number of minor PLA spherulites were detected using POM in the presence of the Co0.9Cu0.1Fe2O4 ceramic magnetic nanoparticles (AM), increasing with AM nanoparticle contents. X-ray diffraction (XRD) analysis showed that the presence of nanoparticles led to an increase in the intensity of diffraction peaks. The DSC findings implied that the crystallization behaviours for the efficient PLA as well as its nanocomposites were affected by the addition of AM nanoparticles. They act as efficient nucleating agents because they shift the temperature of crystallization to a lower value. The Avrami models were used to analyse kinetics data. The experimental data were well described using the Avrami method for all samples tested. The addition of AM to the PLA matrix resulted in a decrease in the crystallization half-time t1/2 values, indicating a faster crystallization rate. TGA data showed that the occurrence of AM nanoparticles decreased the thermal stability of PLA.

2.
Heliyon ; 10(7): e28622, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38689963

ABSTRACT

To eliminate the hazardous pesticide 2,4-dichlorophenylacetic acid (2,4-D) through aqueous solutions, stacked nanorods known as hetero bimetallic organic frameworks (MOFs) of 2-methyl imidazole based on lanthanum and zinc are created. The research's convincing discoveries displayed that La/Zn-MOF is an actual adsorbent for the removal of 2,4-D through aqueous solutions. The La/Zn-MOF was investigated using a variability of techniques, with scanning electron microscope (SEM), powered X-ray diffraction (PXRD), and Brunauer-Emmett-Teller (BET) investigation. La/Zn-MOF has a significant pore capacity of 1.04 cm³/g and a comparatively large surface area of 897.69 m2/g. Our findings, which are quite intriguing, demonstrate that adsorption behavior is pointedly wedged by variations in pH. A pH 6 dose of 0.02 g was shown to be the optimal setting for the greatest capacity for adsorption. Because adsorption is an endothermic process, temperature variations affect its capability. The adsorption method was fit both isothermally and kinetically using the Langmuir isotherm classical. It was created that the entire process made use of a chemisorption mechanism. Solution pH, temperature, adsorbent dosage, and time were all improved using the Box-Behnken design (BBD) and Response Surface Methodology (RSM). We were able to accurately calculate the values of ΔHo, ΔSo, and ΔGo for 2,4-D by following the guidelines. These results demonstrated the spontaneous and endothermic character of the adsorption procedure employing La/Zn-MOF as an adsorbent. Adsorption-desorption cycles can be carried out up to five times. With the synthesized La/Zn-MOF adsorbent due to its exceptional reusability. Many processes, such π-π interaction, pore filling, H-bonding, or electrostatic contact, were postulated to explain the connection between La/Zn-MOF and 2,4-D after extra research to appreciate well the link was conducted. This is the first study to demonstrate the effectiveness of utilizing La/Zn-MOF as an adsorbent to eliminate 2,4-D from wastewater models. The results display that a pH of 6 is required to achieve the maximal 2,4-D adsorption capability on La/Zn-MOF, which is 307.5 mg/g.

3.
Environ Technol ; : 1-23, 2023 Nov 12.
Article in English | MEDLINE | ID: mdl-37953534

ABSTRACT

ABSTRACTResearch efforts are focusing on investigating cost-effective and ecologically friendly ways to create nanoparticles as a result of promising developments in green technology (NPs). This experiment focused on the effectiveness of using biochar (TWB) made from coffee waste to extract levofloxacin (LEV) from water. The conclusive results of the trials showed that TWB is an effective adsorbent for removing LEV from liquid solutions. The TWB produced through biological processes underwent comprehensive analysis using techniques such as X-ray diffractometry (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller surface area measurement (BET), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy. The bioengineered TWB's exceptional crystalline properties, which closely resemble the monoclinic structure of bulk TWB, were confirmed by the XRD analysis. Based on the scanning electron microscopy (SEM) data, the synthesis of TWB Nanoparticles resulted in the formation of spherical particles with an approximate diameter of 40 nm, accompanied by a substantial surface area of 285.55 m²/g. The Pseudo-Second-Order model, which best captured Levofloxacin's adsorption characteristics, was evaluated on the TWB, and the results showed that external mass transfer was the main determinant of response rate. It was also found that the adsorption process was endothermic and spontaneous. The system was optimized using the Box-Behnken design (BBD) methodology. The achieved removal capacity of 1119.19 mg/g utilizing the tested adsorbent was determined to be reasonable when compared to the performance of other previously used adsorbents when evaluating the effectiveness of eliminating LEV. The process of LEV adsorption onto TWB involves a number of different mechanisms, such as ion exchange, π-π interactions, electrostatic pore filling, and hydrogen bonding. Following extensive testing in connection with a real-world sample, the adsorbent demonstrated remarkable efficacy, and it maintained good performance even after undergoing three further regeneration cycles. By adjusting the annealing temperature, we controlled the synthesis of TWB nanoparticles across a range of sizes in order to maximize their antibacterial capabilities. This research utilized a pair of Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and a pair of Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli) to evaluate the antibacterial efficacy of TWB.


Green synthesis of biochar via using tea waste.Adsorption studies of harmful pesticides Levofloxacin (LEV).The adsorbents exhibited good reusability for four adsorption/desorption cycles.Adsorption fit with pseudo second order kinetics and Langmuir isotherm model.The adsorption fitted to pseudo-second-order kinetically.This system will provide helpful guidance for coloured effluent treatment.Optimized the results by using Box-Behnken design.

4.
ACS Omega ; 7(13): 11044-11056, 2022 Apr 05.
Article in English | MEDLINE | ID: mdl-35415323

ABSTRACT

A dependent step-by-step study that included experimental and field study was applied to explore the simplest and most effective system that could be applied for adsorption of Congo Red (CR) dye from the effluent of wastewater that comes out from different industries. Zeolite (Z) surface and pores were subjected to a modification process using green seaweed (GS) algae. Thereafter, each Z, GS, and composite from both were evaluated based on the adsorption efficacy to clean up CR dyes from aqueous solutions. A wet impregnation method was followed to fabricate the zeolite/algae (ZGS) nanocomposite which was characterized using the most appropriate characterization techniques. Batch experiments were selected to be the method of choice in order to follow up the performance of the adsorption process versus different practical variables. Moreover, dye adsorption kinetics and isotherms were investigated as well. At lowered concentrations of CR, the novel nanocomposite ZGS revealed more efficacy than its counterparts, Z and GS, in terms of the adsorption capacity. The maximum adsorption capacities were found to be 8.10, 10.30, and 19.70 mg/g for Z, GS, and ZGS, respectively. Laboratory tests confirmed that the novel nanocomposite ZGS could be introduced as a new and economical nanoadsorbent to capture and remove negatively charged dyes from wastewater effluents that come out from industries at lower concentrations of CR dye and analogous compounds. The dye adsorption on GS, Z, and ZGS coincide with the pseudo-first, Langmuir isotherm, and second-order models. Evaluation for the sorption mechanism was conducted using a diffusion model known as Weber's intraparticle. Depending on the last findings, field experiments on removing dyes from industrial wastewater revealed optimistic findings as the efficiency of our modern and eco-friendly nanoadsorbent reached 91.11%, which helps in the reuse of industrial wastewater.

5.
Polymers (Basel) ; 14(3)2022 Jan 23.
Article in English | MEDLINE | ID: mdl-35160446

ABSTRACT

Herein, a new homologues series of fluorinated liquid crystal compounds, In, 4-(((4-fluorophenyl)imino)methyl)-2-methoxyphenyl 4-alkoxybenzoate were synthesized and its mesomorphic properties were investigated both experimentally and theoretically. The synthesized compounds were characterized by elemental analyzer, NMR, and FT-IR spectroscopy to deduce the molecular structures. The differential scanning calorimetry was employed to examine mesophase transitions whereas the polarized optical microscopy was used to identify the mesophases. The obtained results revealed that the purely nematic phase observed in all terminal side chains. All homologues showed to possess monotropic nematic mesophases except the derivative I8 exhibits enantiotropic property. The optimized geometrical structures of the present designed groups have been derived theoretically. The experimental data was explained using density functional theory computations. The estimated values of dipole moment, polarizability, thermal energy, and molecule electrostatic potential demonstrated that the mesophase stability and type could be illustrated. Binary phase diagram was constructed and addressed in terms of the mesomorphic temperature range and obtained polymorphic phases. It was found that incorporation of the terminal F-atom and lateral CH3O group influence both conformation and steric effect in pure and mixed states. The absorption and fluorescence emission spectra of fabricated films were recorded to elucidate the impact of terminal side chain on photophysical properties of synthesized liquid crystal. It was noted that the increase of terminal side chain length lead to reduction of optical band gap, whereas charge carrier lifetime increases.

6.
Sci Rep ; 11(1): 21058, 2021 10 26.
Article in English | MEDLINE | ID: mdl-34702834

ABSTRACT

A comprehensive study combined experimental, computational and field experiments was conducted to find out the most appropriate adsorbent system for industrial elimination of congo red (CR) dye from simulated industrial wastewater. Modification of the zeolite (Z) by the Padina gymnospora algae (PG) (Egyptian marine algae) was evaluated in terms of the adsorption capability of the zeolite (Z) to remove CR dye from aqueous solutions. The zeolite/algae composite (ZPG) was fabricated using the wet impregnation technique. Various techniques were used to characterize the PG, Z, and the produced ZPG nanocomposite. Batch experiments were performed to study the influence of various practical variables on adsorption processes. The isotherms and kinetics of dye adsorption were also studied. The newly synthesized ZPG nanocomposite exhibits much higher adsorption capacity, especially at low CR concentrations than that of Z. The computational calculations have shown that owing to the presence of intermolecular interactions, the adsorption of the CR molecule on zeolite surfaces is exothermic, energetically favorable, and spontaneous. For all configurations, increasing the zeolite size does not have a noticeable impact on the adsorption energies. The experimental results revealed that the ZPG nanocomposite can be applied as an economical nanoadsorbent to eliminate anionic dyes from simulated industrial wastewater at low CR dye concentrations. The adsorption isotherm of dye onto Z, PG, and ZPG almost agreed with Langmuir isotherm and pseudo-second-order kinetics. The sorption mechanism was also evaluated using Weber's intra-particle diffusion module. Finally, the field experiments revealed optimistic results for the newly synthesized adsorbent in removing dyes from industrial wastewater with 82.1% efficiency, which in turn confirmed the foundation of new eco-friendly materials that aid in the reuse of industrial wastewater.

7.
Nanomaterials (Basel) ; 11(9)2021 Sep 19.
Article in English | MEDLINE | ID: mdl-34578757

ABSTRACT

Systematic investigations involving laboratory, analytical, and field trials were carried out to obtain the most efficient adsorbent for the removal of congo red (CR) dye from industrial effluent. Modification of the zeolite (Z) by the Acanthophora Spicifera algae (AS; marine algae) was evaluated in terms of adsorption capability of the zeolite to remove CR dye from aqueous solution. The zeolite/algae composite (ZAS) was fabricated using the wet impregnation technique. The AS, Z, and the synthesized ZAS composite were analyzed utilizing various characterization techniques. The newly synthesized ZAS composite has an adsorption capacity that is significantly higher than that of Z and AS, particularly at low CR concentrations. Batch experiments were carried out to explore the effects of different experimental factors, as well as the dye adsorption isotherms and kinetics. Owing to the presence of intermolecular interactions, the computational analysis showed that the adsorption of the CR molecule on zeolite surfaces is exothermic, energetically favorable, and spontaneous. Furthermore, growing the zeolite surface area has no discernible effect on the adsorption energies in all configurations. The ZAS composite may be used as a low-cost substitute adsorbent for the removal of anionic dyes from industrial wastewater at lower dye concentrations, according to the experimental results. Adsorption of CR dye onto Z, AS, and ZAS adsorbents was adequately explained by pseudo-second-order kinetics and the Langmuir isotherm. The sorption mechanism was also evaluated using Weber's intra-particle diffusion module. Finally, field testing revealed that the newly synthesized adsorbent was 98.0% efficient at extracting dyes from industrial wastewater, proving the foundation of modern eco-friendly materials that aid in the reuse of industrial wastewater.

8.
Nanomaterials (Basel) ; 11(8)2021 Aug 22.
Article in English | MEDLINE | ID: mdl-34443972

ABSTRACT

Silver nanoparticles (Ag NPs) were decorated with different amounts on the exterior walls of carbon nanotubes (CNTs) by a laser ablation assisted method, especially in liquid media to be applied as a good adsorption material against naphthalene. The laser ablation time was controlled the amount of decoration Ag NPs on CNTs. The prepared nanocomposite was analyzed via different analytical techniques. Ag NPs with a small size distribution of 29 nm are uniformly decorated with spherical shape on CNTs walls. The disorder degree of tubular structure and shifting of the vibrational characteristic peaks increase with the increase in the decoration of Ag NPs. After that, the prepared samples were investigated for the removal of naphthalene. These studies of loading Ag NPs with different amounts on the surface of CNTs act as a promising material for water treatment.

9.
Nanomaterials (Basel) ; 11(7)2021 Jun 28.
Article in English | MEDLINE | ID: mdl-34203125

ABSTRACT

Incorporating nanostructured metal and metal oxide in a polymer matrix is a strategic way to develop a novel candidate for water bioremediation. In this study, under microwave irradiation, a ZnO-Ag/polypyrrole (PPy) nanocomposite with a core/shell structure was prepared by interfacial polymerization of pyrrole in the presence of ZnO nanoparticles and AgNO3 as an oxidant. The antimicrobial behavior of the ZnO-Ag core combined with the electrical properties of the conducting PPy shell created a special ZnO-Ag/PPy nanocomposite with inherent adsorption behavior and antimicrobial properties. More impressively, the as-prepared ZnO-Ag/PPy displayed enhanced adsorption of Cd2+ and PO43- ions in the mixed solution. At pH 8, it had overall removal efficiencies of 95% and 75% for Cd2+and PO43- ions, respectively. The Freundlich adsorption model, rather than the Langmuir adsorption model, better fits the adsorption isotherm results. The adsorption kinetics also followed the pseudo-second-order kinetic model. Additionally, the engineered nanocomposite demonstrated antifungal activity against different fungi, as well as remarkable antibacterial activity against Gram-negative and Gram-positive bacteria. The synergistic combination of crystallinity, coherence of the ZnO-Ag core in the PPy matrix, and the negative zeta potential all contribute to this nanocomposite's high efficiency. Our results have significant consequences in the wastewater bioremediation field using a simple operation process.

10.
Materials (Basel) ; 14(10)2021 May 16.
Article in English | MEDLINE | ID: mdl-34065725

ABSTRACT

Four new non-symmetrical derivatives based on central naphthalene moiety, 4-((4-(alkoxy)phenyl) diazenyl)naphthalen-1-yl 4-substitutedbenzoate (In/x), were prepared, and their properties were investigated experimentally and theoretically. The synthesized materials bear two wing groups: an alkoxy chain of differing proportionate length (n = 6 and 16 carbons) and one terminal attached to a polar group, X. Their molecular structures were elucidated via elemental analyses and FT-IR and NMR spectroscopy. Differential scanning calorimetry (DSC) and polarized optical microscopy (POM) were carried out to evaluate their mesomorphic properties. The results of the experimental investigations revealed that all the synthesized analogues possess only an enantiotropic nematic (N) mesophase with a high thermal stability and broad range. Density functional theory (DFT) calculations were in accordance with the experimental investigations and revealed that all prepared materials are to be linear and planar. Moreover, the rigidity of the molecule increased when an extra fused ring was inserted into the center of the structural shape, so its thermal and geometrical parameters were affected. Energy gap predictions confirmed that the I16/c derivative is more reactive than other compounds.

11.
Front Chem ; 9: 679885, 2021.
Article in English | MEDLINE | ID: mdl-34150718

ABSTRACT

A new selection of supramolecular liquid crystal complexes based on complementary molecules formed via hydrogen-bonding interactions is reported. All prepared complexes were prepared from 4-n-alkoxybenzoic acid (An) and N-4-cyanobenzylidene-4-n-(hexyloxy)benzenamine (I). FT-IR, temperature gradient NMR, Mass Spectrometer and Chromatography spectroscopy were carried out to confirm the -CN and -COOH H-bonded complexation by observing their Fermi-bands and the effects of the 1H-NMR signals as well as its elution signal from HPLC. Moreover, binary phase diagrams were established for further confirmation. All formed complexes (I/An) were studied by the use of differential scanning calorimetry and their phase properties were validated through the use of polarized optical microscopy Results of mesomorphic characterization revealed that all presented complexes exhibited enantiotropic mesophases and their type was dependent on the terminal lengths of alkoxy chains. Also, the mesomorphic temperature ranges decreased in the order I/A6 > I/A8 > I/A10 > I/A16 with linear dependency on the chain length. Finally, the density functional theory computational modeling has been carried out to explain the experimental findings. The relation between the dimensional parameters was established to show the effect of the aspect ratio on the mesophase range and stability. The normalized entropy of the clearing transitions (∆S/R) was calculated to illustrate the molecular interaction enhancements with the chain lengths.

12.
Molecules ; 26(10)2021 May 19.
Article in English | MEDLINE | ID: mdl-34069646

ABSTRACT

A series of high temperature alkyl and alkoxy biphenyltetracarboxydiimide liquid crystals have been prepared under ball mill method using solvent-free mechanochemical approach. The thermal properties of the prepared compounds were investigated by deferential scanning calorimetry (DSC) measurements and the textures were identified by polarized optical microscope (POM). The compounds showed smectic mesomorphic behaviour. The results showed the increasing nature of transition temperature Cr-SmC with chain length with increments of the SmC mesophase range. However, the mesophase range of the SmA was decreased with the terminal chain length either for the alkyl or alkoxy terminal groups. Moreover, the DFT theoretical calculations have been conducted give a detailed projection of the structure of the prepared compounds. A conformational investigation of the biphenyl part has been studied. A deep illustration of the experimental mesomorphic behaviour has been discussed in terms of the calculated aspect ratio. A projection of the frontier molecular orbitals as well as molecular electrostatic potential has been studied to show the effect of the polarity of the terminal chains on the level and the gab of the FMOs and the distribution of electrostatic charges on the prepared molecules.

13.
Molecules ; 25(7)2020 Mar 28.
Article in English | MEDLINE | ID: mdl-32231036

ABSTRACT

New five rings architecture of 1:1 supramolecular hydrogen bonded (H-bonded) complexes were formed between 4-(2-(pyridin-4-yl)diazenyl-3-methylphenyl 4-alkoxybenzoates and 4-n-alkoxyphenyliminobenzoic acids. Mesomorphic and optical behaviors of three systems designed complexes were investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). H-bonded interactions were confirmed via FT-IR spectroscopy. Computational calculations were carried out by density functional theory (DFT) estimation for all formed complexes. Experimental evaluations were correlated with the theoretical predictions and results revealed that, all prepared complexes possessing enantiotropic tri-mesophases with induced smectic C (SmC) and nematic temperature ranges. Moreover, DFT predicted for all formed supramolecular complexes possessing a non-linear bent geometry. Moreover, the π-π stacking of the aromatic rings plays an important role in the mesomorphic properties and thermal stabilities of observed phases. The energy changes between frontier molecular orbitals (HOMO and LUMO) and the molecular electrostatic potential (MEP) of the designed complexes were discussed and related to the experimental results.


Subject(s)
Hydrogen Bonding , Liquid Crystals/chemistry , Macromolecular Substances/chemistry , Density Functional Theory , Magnetic Resonance Spectroscopy , Microscopy, Polarization , Models, Chemical , Models, Molecular , Spectroscopy, Fourier Transform Infrared
14.
Molecules ; 25(7)2020 Mar 26.
Article in English | MEDLINE | ID: mdl-32225057

ABSTRACT

New geometrical architectures of chair- and V-shaped supramolecular liquid crystalline complexes were molded through 1:1 intermolecular hydrogen bonding interactions between 4-(4-(hexyloxy)phenylazo)methyl)phenyl nicotinate and 4-alkoxybenzoic acids. The length of terminal alkoxy acid chains varied, n = 6 to 16 carbons. The mesomorphic behaviour of these complexes was examined through differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Fourier-transform infrared spectroscopy (FT-IR) was carried out to confirm the presence of Fermi bands that appeared for the hydrogen bonding formation. Enantiotropic nematic phases were observed and covered all lengths of alkoxy chains. The geometrical structures of the prepared supramolecular complexes geometries were estimated by Density functional theory (DFT) calculations. The supramolecular complexes I/An are projected to exhibit a nonlinear geometry with V-shaped and chair-shaped geometry. The chair-shaped conformers of I/An were found to be more stable than V-shaped isomeric complexes. Moreover, the effect of the change of the mesogenic core on the mesophase thermal stability (TC) has been investigated by a comparative study of the present azo supramolecular H-bonding LCs (SMHBCs) I/An and our previously reported their Schiff base analogue complexes, II/An. The findings of the DFT illustrated the high impact of CH=N as a mesogenic core on the mesomorphic behavior in terms of the competitive lateral and terminal intermolecular interactions as well as the molecular electrostatic potential (MEP).


Subject(s)
Azo Compounds/chemistry , Density Functional Theory , Hydrogen Bonding , Macromolecular Substances/chemistry , Models, Molecular , Niacin/analogs & derivatives , Niacin/chemistry , Calorimetry, Differential Scanning , Schiff Bases/chemistry , Spectroscopy, Fourier Transform Infrared , Temperature , Thermodynamics
15.
Molecules ; 25(6)2020 Mar 20.
Article in English | MEDLINE | ID: mdl-32245001

ABSTRACT

New mesomorphic symmetrical 2:1 supramolecular H-bonded complexes of seven phenyl rings were prepared between 4-n-alkoxyphenylazobenzoic acids and 4-(2-(pyridin-3-yl)diazenyl)phenyl nicotinate. Mesomorphic studies of the prepared complexes were investigated using differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Fermi bands of the formed H-bonded interactions were confirmed by FT-IR spectroscopy. Geometrical parameters for all complexes were performed using the density functional theory (DFT) calculations method. Theoretical results revealed that the prepared H-bonded complexes are in non-linear geometry with U-shaped and wavy-shaped geometrical structures; however, the greater linearity of the wavy-shaped compounds could be the reason for their stability with respect to the U-shaped conformer. Moreover, the stable, wavy shape of supramolecular H-bonded complexes (SMHBCs) has been used to illustrate mesomeric behavior in terms of the molecular interaction. The experimental mesomorphic investigations revealed that all complexes possess enantiotropic smectic C phase. Phases were confirmed by miscibility with a standard smectic C (SmC) compound. A comparison was constructed to investigate the effect of incorporating azophenyl moiety into the mesomeric behavior of the corresponding five-membered complexes. It was found that the addition of the extra phenylazo group to the acid moiety has a great increment of the mesophase stability (TC) values with respect to the monotropic SmC phase of the five aromatic systems to the high stable enantiotropic SmC mesophase.


Subject(s)
Hydrogen Bonding , Macromolecular Substances/chemistry , Density Functional Theory , Models, Molecular , Models, Theoretical , Molecular Structure , Spectrum Analysis
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