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1.
Biometals ; 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39240269

RESUMO

New solvated Mo(VI) complexes were isolated from the reaction of [MoO2(acac)2] with asymmetric isatin bisthiocarbohydrazone ligands. The ligands were obtained from the reaction of isatin monothiocarbohydrazone with 3,5-dibromo salicylaldehyde (L1), 3,5-dichloro salicylaldehyde (L2) and 3-chloro-5-bromo salicylaldehyde (L3), respectively. In the complexes, the ligands serve as ONS donors and coordinate to the [MoO2]2+ nucleus. The bonding sites are azomethine nitrogen atom, phenolic oxygen atom and thiol sulfur atom. The sixth coordination site is completed by an oxygen atom from an ethanol solvent. The ethanol-coordinated Mo(VI) complexes, C1-C3, [MoO2L(EtOH)] (L: L1-L3), were characterized using elemental analysis, IR and 1H NMR spectroscopies, and conductivity measurements. By crystallizing ethanol-solvated solid complexes from an EtOH/DMSO mixture, DMSO-solvated complexes (C4-C6) suitable for X-ray crystallography were obtained. Crystal structure analysis supports the proposed complex structures and geometries, but the ethanol in the sixth coordination site has been replaced by DMSO. When the anticarcinogenic effects of the ligands and complexes (C1-C3) on the C6 cell line were examined, it was found that the complexes showed higher activity than the ligands. The C3 complex appears to have the best anti-cancer activity compared to doxorubicin. Additionally, all compounds were determined to have high total antioxidant capacity. Data obtained from theoretical studies (DFT and docking) support experimental studies.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39129167

RESUMO

INTRODUCTION: It has been reported that the extension of conjugation in chalcone scaffolds considerably enhanced the potency, selectivity, reversibility, and competitive mode of MAO-B inhibition. In this study, using the experimental results of IC50 values of fifteen halogenated conjugated dienone derivatives (MK1-MK15) against MAO-B, we developed a 3DQSAR model. METHODS: Further, we created a 3D pharmacophore model in active compounds in the series. The built model selected three variables (G2U, RDF115m, RDF155m) among the 653 AlvaDesc molecular descriptors, with a r2 value of 0.87 and a Q2 cv for cross-validation equal to 0.82. The three variables were mostly associated with the direction of symmetry and the likelihood of discovering massive atoms at great distances. The evaluated molecules exhibited a good correlation between experimental and predicted data, indicating that the IC50 value of the structure MK2 was related to the interatomic distances of 15.5 Å between bromine and chloro substituents. Furthermore, the molecules in the series with the highest activity were those with enhanced second component symmetry directional index from the 3D representation, which included the structures MK5 and MK6. RESULT: Additionally, a pharmacophore hypothesis was developed and validated using the decoy Schrodinger dataset, with an ROC score of 0.87 and an HHRR 1 fitness score that ranged from 2.783 to 3.00. The MK series exhibited a significant blood-brain barrier (BBB) permeability, according to exploratory analyses and in silico projections, and almost all analogues were expected to have strong BBB permeability. CONCLUSION: Further DFT research revealed that electrostatics were important in the interactions with MAO-B.

3.
Environ Res ; 260: 119610, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39004393

RESUMO

Photocatalysis has been widely used as one of the most promising approaches to remove various pollutants in liquid or gas phases during the last decade. The main emphasis of the study is on the synergy of vacancy engineering and heterojunction formation, two widely used modifying approaches, to significantly alter photocatalytic performance. The vacancy-induced Ag2CO3/BiOBr/WO3-x heterojunction system has been fabricated using a co-precipitation technique to efficiently abate methylene blue (MB) dye and doxycycline (DC) antibiotic. The as-fabricated Ag2CO3/BiOBr/WO3-x heterojunction system displayed improved optoelectronic characteristic features because of the rational combination of dual charge transferal route and defect modulation. The Ag2CO3/BiOBr/WO3-x system possessed 97% and 74% photodegradation efficacy for MB and DC, respectively, with better charge isolation and migration efficacy. The ternary photocatalyst possessed a multi-fold increase in the reaction rate for both MB and DC, i.e., 0.021 and 0.0078 min-1, respectively, compared to pristine counterparts. Additionally, more insightful deductions about the photodegradation routes were made possible by the structural investigations of MB and DC using density functional theory (DFT) simulations. This study advances the understanding of the mechanisms forming visible light active dual Z-scheme heterojunction for effective environmental remediation.


Assuntos
Poluentes Químicos da Água , Poluentes Químicos da Água/química , Catálise , Teoria da Densidade Funcional , Bismuto/química , Tungstênio/química , Fotólise , Óxidos/química , Azul de Metileno/química , Compostos de Prata/química
4.
Food Chem ; 460(Pt 2): 140516, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39083963

RESUMO

Given the high antioxidant capacity of gallic acid (GA), there is a great deal of interest in the development of rapid, selective, simple, and easily accessible analytical methods for its determination from complex samples. Consequently, the present study aimed to develop an ultrasonic assisted magnetic ionic liquid-based dispersive liquid microextraction (UA-MIL-DLLME) method for the extraction of GA from various samples prior to its spectrophotometric detection. The method's key variables were optimized through statistical analysis. Four magnetic liquids (MILs) were prepared and tested to extract the GA-Se complex formed in aqueous solution. Both experimental studies and theoretical calculations demonstrated that the most suitable MIL for the phase separation of the relevant complex is [P6,6,6,14][Mn(hfacac)3]. The developed UA-MIL-DLLME method exhibited a wide linear range (5-400 ng mL-1), a remarkable enhancement factor (133), and a low limit of detection (1.6 ng mL-1). Additionally, high extraction recovery (97 ± 1%) with a low relative standard deviation (1.9%) was achieved. The extraction time for the UA-MIL-DLLME method was 8 min. The precision of the method was evaluated through repeatability and reproducibility studies. Finally, the UA-MIL-DLLME method was successfully applied to the extraction of the GA from complex samples using a reference method.


Assuntos
Ácido Gálico , Líquidos Iônicos , Microextração em Fase Líquida , Ácido Gálico/química , Ácido Gálico/isolamento & purificação , Ácido Gálico/análise , Líquidos Iônicos/química , Microextração em Fase Líquida/métodos , Teoria da Densidade Funcional , Modelos Estatísticos , Limite de Detecção
5.
Environ Res ; 259: 119575, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38986799

RESUMO

NH2-functionalized metal-organic frameworks (NH2-functionalized MOFs) can abate organic pollutants, predominantly favored by their chemical, mechanical, and thermal stabilities. The present review stated the chemistry of identifying NH2-functionalization and its role in enhancing the properties of bare MOFs. The integration of the amine group bestows several advantages: 1.) enabling band structure modification, 2.) establishing strong metal-NH2 bonds, 3.) preserving MOF structures from reactive oxygen species, and 4.) shielding MOF structures against pH alterations. Consequently, the NH2-functionalized MOFs are promising materials for the photodegradation of organic contaminants. The following section illustrates the two approaches (pre-synthetic and post-synthetic) for NH2-functionalized MOFs. Nevertheless, specific intrinsic limitations, entailing a high recombination rate of charge carriers and inadequate optical adsorption, restrain the applicability of NH2-functionalized MOFs. Accordingly, the succeeding segment presents strategies to elevate the photocatalytic activities of NH2-functionalized MOFs via heterojunction fabrication. The importance of the NH2-functionalized MOFs-based heterojunction has been evaluated in terms of the effect on the enhancement of charge separation, optical adsorption, and redox ability of charge carriers. Subsequently, the potential application for organic pollutant degradation via NH2-functionalized MOFs-based heterojunctions has been scrutinized, wherein the organic pollutants. Eventually, the review concluded with challenges and potential opportunities in engaging and burgeoning domains of the NH2-functionalized MOFs-based heterojunctions.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Catálise , Recuperação e Remediação Ambiental/métodos , Poluentes Ambientais/química , Fotólise , Processos Fotoquímicos
6.
Chemosphere ; 355: 141696, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38499077

RESUMO

The present study investigated the removal of malachite green dye from aquifers by means of microalgae-derived mesoporous diatom biosilica. The various process variables (dye concentration, pH, and adsorbent dose) influencing the removal of the dye were optimized and their interactive effects on the removal efficiency were explored by response surface methodology. The pH of the solution (pH = 5.26) was found to be the most dominating among other tested variables. The Langmuir isotherm (R2 = 0.995) best fitted the equilibrium adsorption data with an adsorption capacity of 40.7 mg/g at 323 K and pseudo-second-order model (R2 = 0.983) best elucidated the rate of dye removal (10.6 mg/g). The underlying mechanism of adsorption was investigated by Weber-Morris and Boyd models and results revealed that the film diffusion governed the overall adsorption process. The theoretical investigations on the dye structure using DFT-based chemical reactivity descriptors indicated that malachite green cations are electrophilic, reactive and possess the ability to accept electrons, and are strongly adsorbed on the surface of diatom biosilica. Also, the Fukui function analysis proposed the favorable adsorption sites available on the adsorbent surface.


Assuntos
Diatomáceas , Microalgas , Poluentes Químicos da Água , Adsorção , Cinética , Corantes de Rosanilina/química , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química , Termodinâmica
7.
Environ Res ; 250: 118519, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382660

RESUMO

The present study explores visible light-assisted photodegradation of ciprofloxacin hydrochloride (CIP) antibiotic as a promising solution to water pollution. The focus is on transforming the optical and electronic properties of BiOCl through the generation of oxygen vacancies (OVs) and the exposure of (110) facets, forming a robust S-scheme heterojunction with WS2. The resultant OVs mediated composite with an optimal ratio of WS2 and BiOCl-OV (4-WS2/BiOCl-OV) demonstrated remarkable efficiency (94.3%) in the visible light-assisted photodegradation of CIP antibiotic within 1.5 h. The CIP degradation using 4-WS2/BiOCl-OV followed pseudo-first-order kinetics with the rate constant of 0.023 min-1, outperforming bare WS2, BiOCl, and BiOCl-OV by 8, 6, and 4 times, respectively. Density functional theory (DFT) analysis aligned well with experimental results, providing insights into the structural arrangement and bandgap analysis of the photocatalysts. Liquid chromatography-mass spectrometry (LC-MS) analysis utilized for identifying potentially degraded products while scavenging experiments and electron paramagnetic resonance (EPR) spin trapping analysis elucidated the S-scheme charge transfer mechanism. This research contributes to advancing the design of oxygen vacancy-mediated S-scheme systems in the realm of photocatalysis, with potential implications for addressing water pollution concerns.


Assuntos
Ciprofloxacina , Oxigênio , Fotólise , Águas Residuárias , Poluentes Químicos da Água , Ciprofloxacina/química , Poluentes Químicos da Água/química , Águas Residuárias/química , Oxigênio/química , Bismuto/química , Antibacterianos/química , Tungstênio/química , Catálise , Luz , Teoria da Densidade Funcional
8.
Chem Biodivers ; 21(4): e202301861, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367267

RESUMO

The paper is focused on biological activity and theoretical study of the structure and properties of a new azo derivative of ß-diketones and its complexes with some metals. The aim of our work was to study the structure and properties of the newly synthesized compound as well as to theoretically determine the possibility of complex formation with the Cu(II) or Co(II) ions. A compound with the same substituents R1=R2=CH3 was chosen for the study. A synthesized azo compound based on 4-amino antipyrine and its complexes with Cu(II), Co(II) in solution and solid phase is reported. The structures of these compounds have been testified by X-ray, IR and  NMR spectroscopy. The combined experimental and theoretical approach was used. To study the structure and properties of the synthesized compound, as well as its possible complex formation with the Cu(II), quantum-chemical calculations were carried out the 6-31G basis set and the electron density functional theory (DFT) method. These 3-(1-phenyl-2,3-dimethyl-pyrazolone-5) azopentadione-2,4 (PDPA) with Cu(II) and Co(II) complexes had effective inhibition against butyrylcholinesterase and acetylcholinesterase. IC50 values were found as 19.03, 3.64 µM for AChE and 28.47, 8.01 µM for BChE, respectively. Cholinesterase inhibitors work to slow down the acetylcholine's deterioration.


Assuntos
Butirilcolinesterase , Complexos de Coordenação , Acetilcolinesterase/química , Butirilcolinesterase/química , Complexos de Coordenação/química , Metais/química , Modelos Teóricos , Simulação de Acoplamento Molecular , Cobre/química , Cobalto/química
9.
ACS Omega ; 9(7): 8123-8138, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38405527

RESUMO

New cobalt(II), copper(II), and zinc(II) Schiff metal complexes were synthesized by the condensation reaction of 4-nitrobenzene-1,2-diamine with 3-4-(diethylamino)-2-hydroxybenzaldehyde. Fourier transform infrared, nuclear magnetic resonance, ultraviolet-visible, electron paramagnetic resonance, and high-resolution electrospray ionization mass spectrometry and powder X-ray diffraction were used to characterize the synthesized H2L and its metal complexes. Conductance measurements, magnetic moment estimation, and metal estimation have all been determined and discussed. The electrochemical properties of the synthesized compounds have been determined and discussed using cyclic voltammetry. The molecular structures of H2L and its metal complexes have been optimized using the B3LYP functional and the 6-31G (d,p) basis set, and their parameters have been discussed. The quantum chemical properties of these synthesized compounds have been predicted through charge distribution and molecular orbital analysis. The biological properties of the synthesized compounds' antioxidant, antifungal, and antibacterial activity have been studied and discussed. Furthermore, H2L and its complexes have been docked with HER2-associated target proteins in breast cancer.

10.
Nano Lett ; 23(23): 10998-11005, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38048073

RESUMO

We describe here the fabrication of large-area molecular junctions with a configuration of ITO/[Ru(Phen)3]/Al to understand temperature- and thickness-dependent charge transport phenomena. Thanks to the electrochemical technique, thin layers of electroactive ruthenium(II)-tris(phenanthroline) [Ru(Phen)3] with thicknesses of 4-16 nm are covalently grown on sputtering-deposited patterned ITO electrodes. The bias-induced molecular junctions exhibit symmetric current-voltage (j-V) curves, demonstrating highly efficient long-range charge transport and weak attenuation with increased molecular film thickness (ß = 0.70 to 0.79 nm-1). Such a lower ß value is attributed to the accessibility of Ru(Phen)3 molecular conduction channels to Fermi levels of both the electrodes and a strong electronic coupling at ITO-molecules interfaces. The thinner junctions (d = 3.9 nm) follow charge transport via resonant tunneling, while the thicker junctions (d = 10-16 nm) follow thermally activated (activation energy, Ea ∼ 43 meV) Poole-Frenkel charge conduction, showing a clear "molecular signature" in the nanometric junctions.

11.
Phys Chem Chem Phys ; 25(44): 30477-30487, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37921407

RESUMO

This article deals with the issue of perforating point defects (pores) in a bilayer heterostructure composed of striped borophene and graphene. Three types of non-equivalent vacancies of the minimum size are considered. These include a single vacancy and two double vacancies. The study of the properties and stability of the perforating defects in borophene-graphene heterostructures is important given the increasing role of such structures in membranes for water purification, renewable energy generation, and other osmotic applications. Using the DFT method, the atomic configurations and main energy characteristics of the proposed defects are obtained. The results show that the formation of a single boron vacancy on the borophene side of borophene-graphene requires less energy than the formation of a carbon vacancy in graphene. Comparisons between double vacancies in nanoscale materials are unreliable because different reference systems produce the different chemical potentials. The problem of choosing the reference system for reliable calculation of the vacancy formation energies is posed and discussed. Using borophene-graphene as an example, it is shown that the reference system strongly affects the magnitude and sign of the vacancy formation energy. Hydrogenation is tested to stabilize the proposed defects.

12.
Molecules ; 28(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38005181

RESUMO

Cancer is a disease that occurs as a result of abnormal or uncontrolled growth of cells due to DNA damage, among many other causes. Certain cancer treatments aim to increase the excess of DNA breaks to such an extent that they cannot escape from the general mechanism of cell checkpoints, leading to the apoptosis of mutant cells. In this study, one of the Sarco-endoplasmic reticulum Ca2+ATPase (SERCA2a) inhibitors, Istaroxime, was investigated. There has been very limited number of articles so far reporting Istaroxime's anticancer activity; thus, we aimed to evaluate the anticancer effects of Istaroxime by cell proliferation assay and revealed the cytotoxic activity of the compound. We further determined the interaction of Istaroxime with topoisomerase enzymes through enzyme activity tests and detailed molecular modeling analysis. Istaroxime exhibited an antiproliferative effect on A549, MCF7, and PC3 cell lines and inhibited Topoisomerase I, suggesting that Istaroxime can act as a Topoisomerase I inhibitor under in vitro conditions. Molecular docking analysis supported the experimental observations. A chemical reactivity analysis of the Istaroxime molecule was made in the light of Density Functional Theory computations. For this aim, important chemical reactivity descriptors such as hardness, electronegativity, and electrophilicity were computed and discussed as detailed.


Assuntos
Antineoplásicos , Etiocolanolona , Simulação de Acoplamento Molecular , Teoria da Densidade Funcional , Etiocolanolona/farmacologia , Antineoplásicos/farmacologia
13.
J Phys Chem A ; 127(39): 8228-8237, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37751600

RESUMO

Analytic Fukui functions calculated at a first-principles level are combined with experimental pKa values and the calculation of tautomerization energies to obtain the effective regioselectivity of uric acid toward electron-transfer reactions under different pH conditions. Second-order electron binding energies are also computed to determine which of the tautomers is more likely to participate in the electron transfer. A comparison of vertical and adiabatic proton detachment energies allows us to conclude that tautomerization is not mediating deprotonation and that two monoanionic species are of comparable relevance. The main difference between these monoanionic species is the ring that has been deprotonated. Both monoanionic species are produced from a single neutral tautomer and mainly produce a single dianionic tautomer. As a method for the analysis of systems affected by pH such as uric acid, we propose to plot condensed Fukui functions versus pH, allowing us to draw the effect of pH on the regioselectivity of electron transfer in a single image.

14.
Mol Divers ; 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37733243

RESUMO

Diabetes Mellitus (DM) is the globe's common leading disease which is caused by high consumption of glucose. DM compiles groups of metabolic disorders which are characterized by inadequate secretion of insulin from pancreas, resulting in hyperglycemia condition. Many enzymes play a vital role in the metabolism of carbohydrate known as α-amylase and α-glucosidase which is calcium metalloenzyme that leads to breakdown of complex polysaccharides into glucose. To tackle this problem, search for newer antidiabetic drugs is the utmost need for the treatment and/or management of increasing diabetic burden. The inhibition of α-amylase and α-glucosidase is one of the effective therapeutic approaches for the development of antidiabetic therapeutics. The exhaustive literature survey has shown the importance of medicinally privileged triazole specifically 1,2,3-triazol and 1,2,4-triazoles scaffold tethered, fused and/or clubbed with other heterocyclic rings structures as promising agents for designing and development of novel antidiabetic therapeutics. Molecular hybrids namely pyridazine-triazole, pyrazoline-triazole, benzothiazole-triazole, benzimidazole-triazole, curcumin-triazole, (bis)coumarin-triazole, acridine-9-carboxamide linked triazole, quinazolinone-triazole, xanthone-triazole, thiazolo-triazole, thiosemicarbazide-triazole, and indole clubbed-triazole are few examples which have shown promising antidiabetic activity by inhibiting α-amylase and/or α-glucosidase. The present review summarizes the structure-activity relationship (SAR), enzyme inhibitory activity including IC50 values, percentage inhibition, kinetic studies, molecular docking studies, and patents filed of the both scaffolds as alpha-amylase and alpha-glucosidase inhibitors, which may be used for further development of potent inhibitors against both enzymes.

15.
J Mol Graph Model ; 124: 108536, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37300949

RESUMO

Toxicity has been a significant concern for many materials used in the production of solar cells and generally conflicts with its efficacy. Therefore, it is crucial to develop alternative, non-toxic materials to improve the sustainability and safety of solar cell technology. In recent years, computational methods such as Conceptual density functional theory (CDFT) have been increasingly used to study the electronic structure and optical properties of toxic molecules such as dyes, with the goal of designing and modifying these molecules to enhance solar cell efficiency and reduce toxicity. By applying CDFT-based chemical reactivity parameters and electronic structure rules, researchers can gain valuable insights into the performance of solar cells and optimize their design accordingly. In silico studies have been used to screen and design non-toxic dye molecules, which can improve the sustainability and safety of solar cell technology. This review article discusses the applications of CDFT in the analysis of toxic dye molecules for use in solar cells. This review also highlights the importance of using alternative, non-toxic materials in the production of solar cells. The review also discusses the limitations of CDFT and in silico studies and their potential for future research. Finally, the article concludes by emphasizing the potential of in silico/DFT investigations for accelerating the discovery of new and efficient dye molecules for enhancing solar cells' efficiency.


Assuntos
Corantes , Energia Solar , Modelos Moleculares , Corantes/química
16.
Artigo em Inglês | MEDLINE | ID: mdl-37227639

RESUMO

Water contamination by pesticides is increasing dramatically due to population growth and the extensive use of pesticides in agriculture, leading to grave environmental and health concerns. Thus, efficient processes and the design and development of effective treatment technologies are required due to the enormous demand for fresh water. The adsorption approach has been widely used to remove organic contaminants such as pesticides because of its performance, less expense, high selectivity, and simplicity of operation compared to other treatment technologies. Among alternative adsorbents, biomaterials abundantly available for pesticide sorption from water resources have attracted the attention of researchers worldwide. The main objective of this review article is to (i) present studies on a wide range of raw or chemically modified biomaterials potentially effective in removing pesticides from aqueous media; (ii) indicating the effectiveness of biosorbents as green and low-cost materials for removing pesticides from wastewater; and (iii) furthermore, report the application of response surface methodology (RSM) for modeling and optimizing adsorption.

17.
Molecules ; 28(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37110779

RESUMO

The development of corrosion inhibitors with outstanding performance is a never-ending and complex process engaged in by researchers, engineers and practitioners. The computational assessment of organic corrosion inhibitors' performance is a crucial step towards the design of new task-specific materials. Herein, the electronic features, adsorption characteristics and bonding mechanisms of two pyridine oximes, namely 2-pyridylaldoxime (2POH) and 3-pyridylaldoxime (3POH), with the iron surface were investigated using molecular dynamics (MD), and self-consistent-charge density-functional tight-binding (SCC-DFTB) simulations. SCC-DFTB simulations revealed that the 3POH molecule can form covalent bonds with iron atoms in its neutral and protonated states, while the 2POH molecule can only bond with iron through its protonated form, resulting in interaction energies of -2.534, -2.007, -1.897, and -0.007 eV for 3POH, 3POH+, 2POH+, and 2POH, respectively. Projected density of states (PDOSs) analysis of pyridines-Fe(110) interactions indicated that pyridine molecules were chemically adsorbed on the iron surface. Quantum chemical calculations (QCCs) revealed that the energy gap and Hard and Soft Acids and Bases (HSAB) principles were efficient in predicting the bonding trend of the molecules investigated with an iron surface. 3POH had the lowest energy gap of 1.706 eV, followed by 3POH+ (2.806 eV), 2POH+ (3.121 eV), and 2POH (3.431 eV). In the presence of a simulated solution, MD simulation showed that the neutral and protonated forms of molecules exhibited a parallel adsorption mode on an iron surface. The excellent adsorption properties and corrosion inhibition performance of 3POH may be attributed to its low stability compared to 2POH molecules.

18.
Artigo em Inglês | MEDLINE | ID: mdl-36882652

RESUMO

The annual production of wastewater from the olive table industry poses a serious problem owing to its high organic matter load, which is highly concentrated in phenolic compounds (PCs) and inorganic materials. This research used adsorption to recover PCs from table olive wastewater (TOWW). Activated carbon was employed as a novel adsorbent. The activated carbon was obtained from olive pomace (OP) and activated using a chemical agent (ZnCl2). Fourier transform infrared spectroscopy analysis (FTIR), Brunauer-Emmett-Teller analysis (BET), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) were applied to characterize the activated carbon sample. To optimize the biosorption conditions of PCs (adsorbent dose (A), temperature (B), and time (C)), a central composite design (CCD) model was used. An adsorption capacity was 1952.34 mg g-1 for optimal conditions with an activated carbon dose of 0.569 g L-1, a temperature of 39 °C, and a contact time of 239 min. The pseudo-second-order and Langmuir models as kinetic and isothermal mathematical models were proved to be more appropriate for the interpretation of the adsorption phenomenon of PCs. PC recovery was performed in fixed-bed reactors. The results of the adsorption of PCs from TOWW by activated carbon could be an effective process at a low cost.

19.
Mol Divers ; 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36656464

RESUMO

Five new nickel(II) complexes have been synthesised with an NNO donor tridentate aroylhydrazone (HFPB) employing the chloride, nitrate, acetate and perchlorate salts, and all the complexes are physiochemically characterized. Elemental analyses suggested stoichiometries as Ni(FPB)(NO3)]·2H2O (1), [Ni(HFPB)(FPB)]Cl (2), [Ni(FPB)(OAc)(DMF)] (3), [Ni(FPB)(ClO4)]·DMF (4), [Ni(FPB)2] (5). Aroylhydrazone is found coordinating in deprotonated iminolate form in four of the complexes (1, 3, 4, 5) however in one case (complex 2), two aroylhydrazone moieties are binding to the metal centre in the neutral and anionic forms. The structure of the bisligated complex 5, found using single crystal X ray diffraction studies confirmed that the metal has a distorted octahedral N4O2 coordination environment, with each of the two deprotonated ligands coordinating through the pyridine nitrogen, imino-hydrazone nitrogen and the enolate oxygen of the hydrazone moiety. To compare and study, the electronic interactions and stabilities of the metal complexes, various quantum chemical parameters were calculated. Moreover, Hirshfeld surface analysis was carried out for complex 5 to determine the intermolecular interactions. The biophysical attributes of the ligand and complex 5 have been investigated with CT-DNA and experimental outcomes show that the Ni(II) complex exhibited higher binding propensity towards DNA as compared to ligand. Furthermore, to specifically understand the type of interactions of the metal complexes with DNA, molecular docking studies were effectuated. In addition, the electronic and related reactivity behaviors of the ligand and five Ni(II) complexes were studied using B3LYP/6-31 + + G**/LANL2DZ level. As expected, the obtained results from Natural Bond Orbital (NBO) computations displayed that the resonance interactions (n → π* and π → π*) play a determinant role in evaluating the chemical attributes of the reported compounds.

20.
J Phys Chem Lett ; 14(1): 214-220, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36583652

RESUMO

We apply density functional theory to study carrier mobility in a γ-phosphorus carbide monolayer. Although previous calculations predicted high and anisotropic mobility in this material, we show that the mobility can be significantly influenced by common antisite defects. We demonstrate that at equilibrium concentrations defects do not inhibit carrier mobility up to temperatures of 1000 K. However, defects can change the mobility at high nonequilibrium concentrations of about 10-4 to 10-2 defects per atom. At the low end of this concentration range, defects act as traps for charge carriers and inhibit their mobility. At the high end of this range, defects change the effective carrier masses and deformation potentials, and they can lead to both an increase and a decrease in mobility. We also report the Raman and IR spectra associated with antisite defects. We predict new vibrational modes and shifts of the existing modes due to the defects.

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