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1.
J Environ Manage ; 356: 120642, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503227

RESUMO

The polysilicate aluminum ferric (PSAF) was synthesized via copolymerization of polysilicic acid (PSi), AlCl3 and FeCl3 for treating oily wastewater from Daqing gas field. This study investigated the effects of key preparation factors such as the degree of PSi's preactivation and the ratio of (Fe + Al)/Si and Al/Fe on both polymerization and coagulation performance exhibited by PSAF. To determine the optimal timing for introducing Al3+ and Fe3+, zeta potential, viscosity and particle size were investigated. Additionally, infrared spectroscopy, X-ray powder diffraction, polarizing microscopy and scanning electron microscope analysis were employed to investigate the structure and morphology of PSAF. The results indicate that under conditions characterized by a SiO2 mass fraction of 2.5% and pH = 4.5, an optimal timing for introducing Al3+ and Fe3+ is at 100 min when PSi exhibits moderate polymerization along with sufficient stability. When considering molar ratios such as (Al + Fe)/Si being 6:4 and Al/Fe being 5:5, respectively, PSAF falls within a "stable zone" enabling storage period up to 32 days. Moreover, Jar test results demonstrate that at a dosage of 200 mg/L PSAF for oily wastewater treatment in gas fields could reach the maximum turbidity removal efficiency up to 99.5% while oil removal efficiency reach 88.6% without pH adjustment. The copolymerization facilitates the formation of larger PSAF aggregates with positive potential, thereby augmenting the coagulants' adsorption bridging and charge neutralization capabilities. As a result, PSAF has great potential as a practical coagulant for treating oil-containing wastewater in industrial settings.


Assuntos
Águas Residuárias , Purificação da Água , Alumínio/química , Dióxido de Silício , Polímeros , Ferro/química , Purificação da Água/métodos , Compostos Férricos/química
2.
Biofouling ; 40(2): 193-208, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38456659

RESUMO

Updated understanding on the effect of biofouling on corrosion rate is needed to protect marine structures as climate change is altering seawater physiochemistry and biofouling organism distribution. Multi-disciplinary techniques can improve understanding of biofouling development and associated corrosion rates on metals immersed in natural seawater (NSW). In this study, the development of biofouling and corrosion on welded Nickel Aluminium Bronze (NAB) was investigated through long-term immersion tests in NSW, simulated seawater (SSW) and air. Biofouling was affected by geographic location within the marina and influenced corrosion extent. The corrosion rate of NAB was accelerated in the initial months of exposure in NSW (1.27 mm.yr-1) and then settled to 0.11 mm.yr-1 (annual average). This was significantly higher than the 0.06 mm.yr-1 corrosion rate measured in SSW, which matched published rates. The results suggest that corrosion rates for cast NAB should be revised to take account of biofouling and updated seawater physiochemistry.


Assuntos
Incrustação Biológica , Biofilmes , Alumínio/química , Níquel , Corrosão , Água do Mar/química
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 311: 124005, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38341932

RESUMO

In the present study, we have synthesized an aminobenzoic acid containing Schiff base (compound 1) and its structure was confirmed through single crystal X-ray study. Importantly, the compound 1 crystallizes in the zwitterionic form, with an anionic carboxylate group (-COO-) and a cationic iminium group (-C = NH+-). The compound 1 is highly soluble in water due to its zwitterionic feature in the solid state. Interestingly, compound 1 acts as a ratiometric fluorescent probe for the selective detection of Al3+ ion in aqueous solution without organic cosolvent. It can also detect Al3+ ion by visual colour change to bluish-green fluorescence under 365 nm UV light. The association constant between compound 1 with Al3+ ion was estimated to be 1.67 × 104 M-1. The lowest detection limit for Al3+ ion was calculated to be 7.05 × 10-8 M in water. Compound 1 in combination with Al3+ ion demonstrated fluorescent imaging potential of the nucleus of in RAW 264.7 murine macrophage cell line. In addition, the sensing model is developed as paper based sensor ''Test Kit' 'for its practical applicability.


Assuntos
Alumínio , Água , Animais , Camundongos , Alumínio/química , Espectrometria de Fluorescência/métodos , Água/química , Corantes Fluorescentes/química
4.
Carbohydr Polym ; 328: 121726, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38220346

RESUMO

Fluorescent sensors available for metal ions detection have been extensively developed in recent years. However, developing an ultrasensitive fluorescent sensor for highly selectively detecting Al3+ based on cellulose remains a challenge. In this study, an ethylcellulose-based flavonol fluorescent sensor named EC-BHA was synthesized by the esterification of ethylcellulose (EC) with a new flavonol derivative 4-(2-(2,3-bis(ethoxymeothy)phenyl)-3-hydroxy-4-oxo-4-H-chromen-7-yl) benzoic acid (BHA). The fluorescence intensity of EC-BHA exhibited a 180-fold increase at 490 nm after binding with Al3+ and provided an ultralow detection limit of 13.0 nM. The sensor showed some exceptional sensing properties including a broad pH range (4-10), large Stokes shifts (190 nm), and a short response time (3 min). This sensor was successfully applied for determining trace Al3+ in food samples as well as in plant tissue. Moreover, the electrostatic spun film EBP was fabricated by blending EC-BHA with PS (polystyrene) via electrostatic spinning technique and utilized for selective detection of Al3+ as soon as possible.


Assuntos
Alumínio , Corantes Fluorescentes , Corantes Fluorescentes/química , Alumínio/química , Celulose/química , Flavonóis
5.
Chemosphere ; 349: 140649, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37952825

RESUMO

The need to minimize eutrophication in water bodies and the shortage of phosphate rock reserves has stimulated the search for sequestration and recovery of phosphate from alternative sources, including wastewater. In this study, aluminium dross (AD), a smelting industry waste/by-product, was converted to high-value material by encapsulation in calcium alginate (Ca-Alg) beads, viz. Ca-Alg-AD and utilized for adsorptive/uptake removal and phosphate recovery from an aqueous environment. Encapsulation of AD in alginate beads solves serious operational difficulties of using raw AD material directly due to density difference constraining efficient contact of AD with pollutants present in water and post-treatment recovery of AD material. The phosphate removal was evaluated in both batch and continuous flow operation modes. The batch adsorption study revealed 96.86% phosphate removal from 10 mg L-1 of initial phosphate concentration in 70 min of optimal contact time. Further, the phosphate removal potential of Ca-Alg-AD beads turned out to be independent of solution pH, with an average of 95.93 ± 1.40 % phosphate removal in the 2-9 pH range. The result reflects phosphate adsorption on Ca-Alg-AD beads following a second-order pseudo-kinetic model. Ca-Alg-AD beads-based adsorption followed Freundlich and Langmuir isotherm models. Further, a continuous packed bed column study revealed a total phosphate adsorption capacity of 1.089 mg g-1. The chemical composition, physical stability, and surface properties of Ca-Alg-AD beads were analyzed by means of state-of-the-art analytical techniques, such as Scanning Electron Microscopy-Energy Dispersive X-ray spectroscopy (SEM-EDX), Fourier Transform Infrared Spectroscopy (FTIR) and thermogravimetry/Differential Thermal Analysis (TG/DTA). These characterization techniques comprehend the mechanism and influence of surface properties and morphology on the phosphate adsorption behaviour, which induce the involvement of multiple mechanisms such as ligand complexation, ion exchange, and electrostatic attraction for phosphate adsorption on Ca-Alg-AD beads.


Assuntos
Alumínio , Poluentes Químicos da Água , Alumínio/química , Fosfatos/química , Estudos de Viabilidade , Poluentes Químicos da Água/análise , Água , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética , Concentração de Íons de Hidrogênio , Alginatos/química
6.
Methods ; 221: 27-34, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008345

RESUMO

At this "Aluminum Age", exposure to aluminum (metallic or ionic form) is inevitable and inestimable. The presence of aluminum in biological systems is evident but more often aluminum toxicity is less understood. Therefore, the presence of biologically reactive aluminum needs to be identified and quantified. Alongside metals, L-cysteine, an essential amino acid, plays a pivotal role in the homeostasis of cellular oxidative and reductive stress. However, excess (<7g) could be lethal and can lead to death. Thus, in-situ selective detection of aluminum and L-cysteine is of larger interest. Here we report a fluorogenic probe (R) for the sequential selective detection and quantification of Al3+ and L-cysteine in a semi-aqueous medium (3:7; water: DMSO). The probe (R) was synthesized by a one-step acid-mediated condensation reaction between pyridine-3,4-diamine and 2-hydroxy-1-napthaldehyde. The synthesized probe was characterized using 1H and 13C NMR, and HR-Mass spectroscopic techniques. The probe (R) is non-emissive in nature, but on recognition of Al3+, the probe R showed "turn-on" emission (bright yellow colour) showing two emission maxima (522 nm and 547 nm), and no naked eye observable color change. Other competing cations do not show any noticeable fluorescence outcome. The R + Al3+ ensemble can specifically detect L-cysteine among all the essential amino acids by showing a fluorescence "turn-off" response. The sensing mechanism of Al3+ is obeying the chelation-enhanced fluorescence (CHEF) effect. The binding constant of R + Al3+ is 0.3 × 104 M-1. The limit of detection (LoD) for Al3+ and L-cysteine are 2.02 × 10-7 M and 0.5 × 10-5 M respectively. The probe (R) can show maximum efficiency within the pH range (7.0-10.0). The probe is found non-toxic (>80 % cell viability with 15 µM concentration) and employed for the in-vitro fluorescence imaging in the HeLa cell.


Assuntos
Cisteína , Corantes Fluorescentes , Humanos , Células HeLa , Corantes Fluorescentes/química , Alumínio/química , Cátions , Água/química , Espectrometria de Fluorescência/métodos
7.
Environ Sci Pollut Res Int ; 31(1): 1664-1673, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38097845

RESUMO

The subject of the research was the recovery of raw materials from waste generated in the production of cable insulation and the management of aluminum sludge. It was found that 49% (w/w) acetophenone, 6.8% (w/w) α-methylstyrene, and 17.2% (w/w) cumyl alcohol can be recovered from waste with a loss on ignition of 95% and used in various industries. A gas chromatograph equipped with a mass spectrometry detector was used to identify the recovered compounds. A waste distillation process was proposed to remove the water layer and obtain a concentrated acetophenone fraction. A method of neutralizing the water fraction and distillation residues is presented. The proposed waste management method is an alternative method to the currently used thermal transformation method. In turn, aluminum sludge was used to produce aluminum sulfate, which was used in the plant's sewage treatment plant as a coagulant. The effect of this action was a reduction of 67% in the content of total iron, 60% of trivalent iron, and 32% of chemical oxygen demand. The above-mentioned examples of waste management are part of a closed-loop waste management strategy.


Assuntos
Esgotos , Gerenciamento de Resíduos , Esgotos/química , Alumínio/química , Cromatografia Gasosa-Espectrometria de Massas , Água , Ferro , Acetofenonas , Eliminação de Resíduos Líquidos/métodos
8.
World J Microbiol Biotechnol ; 40(1): 36, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38057648

RESUMO

Microorganisms can play a significant role in material corrosion, with bacterial biofilms as major participants in microbially influenced corrosion (MIC). The exact mechanisms by which this takes place are poorly understood, resulting in a scarcity of information regarding MIC detection and prevention. In this work, a consortium of moderately thermophilic bacteria isolated from a biofilm growing over aluminum alloy 7075 was characterized. Its effect over the alloy was evaluated on a 40-day period using Electron Microscopy, demonstrating acceleration of corrosion in comparison to the abiotic control. The bacterial consortium was biochemically and microbiologically characterized as an attempt to elucidate factors contributing to corrosion. Molecular analysis revealed that the consortium consisted mainly of members of the Bacillus genus, with lower abundance of other genera such as Thermoanaerobacterium, Anoxybacillus and Paenibacillus. The EPS polysaccharide presented mainly mannose, galactose, rhamnose and ribose. Our observations suggest that the acidification of the culture media resulting from bacterial metabolism acted as the main contributor to corrosion, hinting at an unspecific mechanism. The consortium was not sulfate-reducing, but it was found to produce hydrogen, which could also be a compounding factor for corrosion.


Assuntos
Ligas , Alumínio , Humanos , Ligas/química , Alumínio/química , Alumínio/metabolismo , Alumínio/farmacologia , Corrosão , Bactérias/metabolismo , Biofilmes , Aço/química
9.
Chemosphere ; 343: 140294, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37758078

RESUMO

There many materials were used in lake restoration to immobilize phosphorus (P) and reduce the effect of eutrophication. Among them, calcium/aluminum composite (CAC) showed a good capacity of P adsorption. However, a comprehensive of its performance, ecological safety, and the mechanism of P passivation in the aluminum-bound P (Al -P) dominated sediments under varying redox conditions remains incomplete. In the current study, both unwashed CAC (UCAC) and washed CAC (WCAC) showed good P adsorption properties, and the greatest maximum capacity for P adsorption (Qmax) reached 206.8 mg/g at pH 8.5 for UCAC. The SRP and TP in the overlying water of the uncapped sediments showed a decrease-increase-decrease trend in a sequence of transition from aerobic to anaerobic to re-aerobic stages. In contrast, the SRP and TP of the two CACs-capped sediments were maintained low. Phosphorus forms in the uncapped sediment also underwent significant changes during continuous variation of dissolved oxygen (DO) levels. In particular, the decrease in iron-bound P (Fe-P) and Al-P was significantly promoted in the anaerobic phase, and the released P was reabsorbed to form mainly Fe-P in the re-aerobic phase. The CACs-capping promoted the transformation of Fe-P to residual P (Res-P), forming a thick static layer in the surface sediment, thus significantly inhibiting sediment P release. Moreover, the CACs-capping did not induce the Al3+ leaching and significant changes of the microbial community in sediments, and their performances of P immobilization could keep stable to resist the redox variation, which promised to be a good choice for P passivation in eutrophic lake sediments dominated by Al/Fe-P. These findings also confirmed that the risk of P release from Al/Fe-P (mainly Al-P)-dominated sediments was strongly influenced by continuously changing redox conditions, and was probably enhanced by the formation of Fe-P from the resorption of the released P.


Assuntos
Alumínio , Poluentes Químicos da Água , Alumínio/química , Cálcio/química , Fósforo/química , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Lagos/química , Cálcio da Dieta , Oxirredução
10.
Sensors (Basel) ; 23(12)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37420673

RESUMO

During the secondary production of aluminum, upon melting the scrap in a furnace, there is the possibility of developing an aluminothermic reaction, which produces oxides in the molten metal bath. Aluminum oxides must be identified and removed from the bath, as they modify the chemical composition and reduce the purity of the product. Furthermore, accurate measurement of molten aluminum level in a casting furnace is crucial to obtain an optimal liquid metal flow rate which influences the final product quality and process efficiency. This paper proposes methods for the identification of aluminothermic reactions and molten aluminum levels in aluminum furnaces. An RGB Camera was used to acquire video from the furnace interior, and computer vision algorithms were developed to identify the aluminothermic reaction and melt level. The algorithms were developed to process the image frames of video acquired from the furnace. Results showed that the proposed system allowed the online identification of the aluminothermic reaction and the molten aluminum level present inside the furnace at a computation time of 0.7 s and 0.4 s per frame, respectively. The advantages and limitations of the different algorithms are presented and discussed.


Assuntos
Óxido de Alumínio , Alumínio , Alumínio/química , Óxidos/química
11.
ACS Chem Neurosci ; 14(15): 2792-2801, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37436111

RESUMO

A new anthracene-based probe (E)-N'-(1-(anthracen-9-yl)ethylidene)-2-hydroxybenzohydrazide (AHB) has been efficiently synthesized and characterized by various spectroscopic methods. It exhibits extremely selective and sensitive fluorometric sensing of Al3+ ions with a large enhancement in the fluorescent intensity due to the restricted photoinduced electron transfer (PET) mechanism with a chelation-enhanced fluorescence (CHEF) effect. The AHB-Al3+ complex shows a remarkably low limit of detection at 0.498 nM. The binding mechanism has been proposed based on Job's plot, 1H NMR titration, Fourier transform infrared (FT-IR), high-resolution mass spectrometry (HRMS), and density functional theory (DFT) studies. The chemosensor is reusable and reversible in the presence of ctDNA. The practical usability of the fluorosensor has been established by a test strip kit. Further, the therapeutic potential of AHB against Al3+ ion-induced tau protein toxicity has been tested in the eye of Alzheimer's disease (AD) model of Drosophila via metal chelation therapy. AHB shows great therapeutic potential with 53.3% rescue in the eye phenotype. The in vivo interaction study of AHB with Al3+ in the gut tissue of Drosophila confirms its sensing efficiency in the biological environment. A detailed comparison table included evaluates the effectiveness of AHB.


Assuntos
Alumínio , Doença de Alzheimer , Animais , Alumínio/análise , Alumínio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Doença de Alzheimer/tratamento farmacológico , Drosophila , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , Antracenos
12.
Chemosphere ; 338: 139503, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37453522

RESUMO

Sulfur dioxide (SO2) gas at trace levels challenges the consumption of fuel gases and cleaning of flue gases originating from diverse anthropogenic sources. We have demonstrated Zn-Al layered double hydroxide (LDH) and layered double oxide (LDO) as low-cost and effective adsorbents in removing lowly concentrated SO2 gas at room temperature. Water in the adsorbent bed significantly improved the performance, where the maximum adsorption capacity of 38.0 mg g-1 was achieved for LDO. Based on the spectroscopic findings, the adsorbed gas molecules were oxidized to surface-bound sulfate/bisulfate species, showing complete mineralization of SO2 molecules. By employing an inexpensive NaOH-H2O2 solution-based regeneration strategy, we successfully regenerated the spent LDO, significantly restoring its gas uptake capacity. The regenerated oxide exhibited an increased gas uptake capacity ranging from 38.0 to 98.5 mg g-1, highlighting the practicality and economic feasibility of our approach. LDH/LDO materials are promising regenerable adsorbents for removing low concentrations of SO2 gas in ambient conditions.


Assuntos
Alumínio , Dióxido de Enxofre , Dióxido de Enxofre/química , Alumínio/química , Óxidos , Hidróxido de Alumínio , Zinco , Temperatura , Peróxido de Hidrogênio , Hidróxidos , Ácidos , Adsorção
13.
J Chem Phys ; 158(22)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37290079

RESUMO

In this study, we investigate the energetics of small aluminum clusters doped with a carbon atom using several computational methods, including diffusion quantum Monte Carlo, Hartree-Fock (HF), and density functional theory. We calculate the lowest energy structure, total ground-state energy, electron population distribution, binding energy, and dissociation energy as a function of the cluster size of the carbon-doped aluminum clusters compared with the undoped ones. The obtained results show that carbon doping enhances the stability of the clusters mainly due to the electrostatic and exchange interactions from the HF contribution gain. The calculations also indicate that the dissociation energy required to remove the doped carbon atom is much larger than that required to remove an aluminum atom from the doped clusters. In general, our results are consistent with available theoretical and experimental data.


Assuntos
Alumínio , Teoria Quântica , Alumínio/química , Método de Monte Carlo , Difusão , Elétrons
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 301: 122981, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321137

RESUMO

A chemosensor with two binding pockets facilitates binding of one metal ion in either of the pockets providing a better chance for the interaction and hence recognition of the cation. We report here a chemosensor, namely 2,2'-(1E)-(5,5'-sulfonylbis(2-hydroxy-5,1-phenylene))bis(azan-1-yl-1-ylidene)bis(methan-1-yl-1-ylidene)dinaphthalen-1-ol (H4L-naph), for selective sensing of Al3+ in DMF- HEPES buffer (1:4, v/v, pH 7.4). It shows almost 100-fold fluorescence enhancement at 532 nm (λex = 482 nm) in the presence of Al3+. Its quantum yield and excited state lifetime enhances significantly with the cations. H4L-naph forms a 1:2 complex with Al3+ with an association constant value of 2.18 × 104 M-2. Fluorescence enhancement may be attributed to CHEFF mechanism and restriction of >CN isomerization. Effect of the presence of naphthyl rings instead phenyl ring of a previously reported probe has resulted shifting of excitation/emission peak towards longer wavelength. The probe has been applied to image Al3+ in L6 cells with no significant cytotoxicity.


Assuntos
Alumínio , Corantes Fluorescentes , Corantes Fluorescentes/química , Alumínio/química , Cátions , Espectrometria de Fluorescência/métodos
15.
J Inorg Biochem ; 246: 112267, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37329775

RESUMO

Theranostic and personalized medicine are blooming strategies to improve oncologic patients' health care and facilitate early treatment. While 18F-radiochemistry for theranostic application is attractive due to its imaging properties, combining diagnosis by positron emission tomography (PET) via aluminum-fluoride-18 and ß- therapy with lutetium-177 is relevant. Nevertheless, it requires the use of two different chelating agents, which are NOTA and DOTA for aluminum-fluoride-18 and lutetium-177 radiolabeling, respectively. To overcome this issue, we propose herein the synthesis of a new hybrid chelating agent named NO2A-AHM, which can be labeled with different types of emitters (ß+, ß- and γ) using the mismatched Al18F/177Lu pair. NO2A-AHM, is based on a hydrazine moiety functionalized by a NOTA cycle, a chelating arm, and a linker with a maleimide function. This design is chosen to increase the flexibility and allow the formation of 5 up to 7 coordination bonds with metal ions. Moreover, this agent can be coupled to targeting moieties containing a thiol function, such as peptides, to increase selectivity towards specific cancer cells. Experimental complexation and computational chemistry studies are performed to confirm the capacity of our chelating agent to label both aluminum-fluoride and lutetium using molecular modeling approaches at Density Functional Theory (DFT) level. The proof of concept of the ability of NO2A-AHM to complex both aluminum-fluoride-18, for PET imaging applications, and lutetium-177 for radiotherapy has shown encouraging results which is prominent for the development of a fully consistent theranostic approach.


Assuntos
Quelantes , Fluoretos , Humanos , Quelantes/química , Alumínio/química , Tomografia por Emissão de Pósitrons , Linhagem Celular Tumoral
16.
Water Res ; 242: 120201, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37336184

RESUMO

Anode fouling is one of the key limiting factors to the widespread application of electrocoagulation (EC) for treatment of different types of contaminated water. Promising mitigation strategy to fouling is to operate the process under polarity reversal (PR) instead of direct current (DC). However, the PR operation comes at the cost of process complexity due to the alternation of electrochemical and chemical reactions. In this study, we systematically investigated the link between evolving fouling layer during DC and PR close to iron and aluminum electrodes and morphological and rheological properties of the formed sludge. By operando visualization of EC process, we demonstrate that during PR operation, precipitation of the iron and aluminum species occurs close to the anode interface, resulting in flocs with higher porosity and lower density than those formed under DC conditions. However, rheological investigation revealed that the PR conditions resulted in a sludge with more pronounced solid-like signature, but this enhancement in its viscoelastic properties is closely related to a period of the current's polarity reversal. We attribute this unexpected result to higher shear rate and collision of particles during PR conditions.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Esgotos , Alumínio/química , Eletrocoagulação , Eletricidade , Eletrodos , Ferro
17.
Sci Rep ; 13(1): 9426, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296212

RESUMO

The relationships between the structural and aggregational state of bovine serum albumin (BSA) and the specific length and total number of zigzag pattern segments of the film textures formed upon drying biopolymer solutions with aluminum and iron chlorides have been shown. To obtain films, saline solutions of BSA were dried in a glass cuvette under thermostatically controlled conditions. It is shown that the formation of zigzag structures is sensitive to the influence of aluminum chlorides Al3+ and iron chlorides Fe3+ and depend on the concentration of AlCl3 and FeCl3. This may be due to a change in the charge and size of BSA particles and due to a change in conformation or a violation of the structure of BSA. These factors, in turn, affect the hydration of the solution components and the structural state of free water in solution, which presumably also affects the formation of zigzag structures. It is established that the analysis of the specific length and the number of segments of zigzag patterns makes it possible to evaluate changes in the state of biopolymers in the initial solution during structural changes and aggregation.


Assuntos
Alumínio , Cloretos , Alumínio/química , Cloretos/química , Soroalbumina Bovina/química , Ferro , Soluções
18.
Chemistry ; 29(33): e202203937, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37017134

RESUMO

The development of molecule-based multifunctional switchable materials that exhibit a switch of polarity and dielectric property are extremely limited. We have demonstrated solvent-vapour-induced reversible molecular rearrangements between nonpolar crystals [Al(sap)(acac)(sol)] (H2 sap=2-salicylideneaminophenol, acac=acetylacetonate, sol=MeOH (1), EtOH (2)) and polar crystal [Al(sap)(acac)(DMSO)] (3). This crystal-to-crystal structural transformation was accompanied by a switch of second harmonic generation (SHG) and dielectric properties, including the formation of ferroelectric domains, thus reflecting the SHG-active polar Cc space group of 3. This is the first reported example of dielectric properties and polarity switching in luminescent mononuclear aluminium(III) complexes, which exhibit strong green emission in the solid state.


Assuntos
Luminescência , Solventes/química , Alumínio/química
19.
Chemistry ; 29(38): e202300654, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37084011

RESUMO

Novel luminescent dialdiminate complexes of the Group 13 elements were prepared to evaluate the effects of the central element on their properties. We demonstrate that their absorption wavelength and the response to Lewis bases apparently depend on the central atom. The aluminum complex exhibited the absorption band in the higher-energy region than the gallium and indium congeners. Theoretical calculations suggest that the aluminum complex has a lower-lying highest-occupied molecular orbital than the other complexes. Additionally, the emission intensity of the aluminum complex clearly changed in response to a Lewis base. Quantum chemical calculations suggest that these element-dependent optical properties could originate from the difference in the electric charges on the central elements. Interestingly, the ligand exchange reactions were observed in the indium complexes together with the changes in the optical properties and controlled by the addition of InCl3 and InMe3 . Furthermore, all the complexes showed aggregation-induced emission enhancement (AIEE) and crystallization-induced emission enhancement (CIEE) properties. These results lead to proposing a practical strategy for manipulating the optoelectronic properties coupled with the reactivities of complexes by choosing the central elements in the same group.


Assuntos
Alumínio , Índio , Índio/química , Alumínio/química , Luminescência
20.
Environ Sci Pollut Res Int ; 30(24): 65712-65727, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37093372

RESUMO

In recent years, metal-organic frameworks (MOFs) have been employed in numerous applications for adsorption. Researchers synthesize new MOFs by various methods, including the introduction of functional groups. In this study, three different aluminum-based MOFs (with non-functionalized, amino-functionalized, nitro-functionalized) were produced by hydrothermal synthesis and used for investigating typical endocrine disrupting chemicals (EDCs), namely for bisphenol A (BPA) adsorption. We used several methods to characterize the MOFs and conducted batch adsorption experiments to investigate their adsorption properties, and explore the influence of different functional groups on adsorption materials. The specific surface area of Al-MOF-NH2 is 6 times larger than that of Al-MOF according to the N2 adsorption and desorption isotherms of the material, that is, the BET of Al-MOF, Al-MOF-NH2, and Al-MOF-NO2 were 109.68, 644.03, and 146.60 m2/g. Note that although the same synthesis method is used, pore size is greatly changed because of the different functional groups. Al-MOF and Al-MOF-NO2 have more mesopores, and Al-MOF-NH2 is mainly microporous. The BPA adsorption capacities of Al-MOF, Al-MOF-NH2, and Al-MOF-NO2 were 46.43, 227.78, and 155.84 mg/L. The outcomes can also be explained by the improved adsorption performance from the addition of amino functional groups. In this research, the adsorption isotherms and adsorption kinetics of the three Al-MOFs for BPA were also investigated to explain the different adsorption properties of various functional groups. The results show that the amino-functionalized materials have remarkable characterization morphologies, uniform particle distributions, appropriate particle sizes, excellent specific surface areas, and superior adsorption effects.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Alumínio/química , Adsorção , Dióxido de Nitrogênio , Água
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