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1.
Chemosphere ; 365: 143244, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39251160

RESUMEN

Dyestuff, one of the most hazardous compounds in terms of threats to people and the environment, is found in wastewater from industrial usage. The removal of Methylene Blue (MB) from a water-based medium has been studied by numerous researchers using a variety of adsorbents. To remove MB from aqueous solution, nano-TiO2/MWCNT/Chitosan hydrogel composite beads (n-TiO2/MWCNT/Cht) were developed in this study using a sol-gel method. This research discusses the characterisation of a new adsorbent substance using Infrared Spectroscopy (FT-IR) analysis and scanning electron microscopy (SEM). The optimal pH, adsorbent dosage, duration, and starting concentration were ascertained by analyzing the removal efficiencies of MB using the batch adsorption method. Adsorption behaviour at the equilibrium state has been investigated using a variety of adsorption isotherms, including Freundlich, Langmuir, and Dubinin-Radushkevich. The Langmuir adsorption isotherm has been useful to clarify adsorption behaviors. nTiO2-Cht/MWCNT had an adsorption capacity of 80.65 mg/g for MB. The pseudo-second-order kinetic model offered the best agreement to the experimental data for the adsorption of MB. Kinetic models of pseudo-first-order and pseudo-second-order were employed to explore the adsorption processes of MB on the n-TiO2/MWCNT/Cht. This study demonstrated the efficiency of n-TiO2/MWCNT/Cht for the removal of MB from a water-based solution.

2.
Polymers (Basel) ; 16(16)2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39204587

RESUMEN

Mercury (Hg) is a toxic element which impacts on biological systems and ecosystems. Because the toxicity of Hg species is highly dependent on their concentration levels and chemical forms, the sensitive identification of the chemical forms of Hg-i.e., Hg speciation-is of major significance in providing meaningful information about the sources of Hg exposure. In this study, a microfluidic-based device made of high-clarity poly(methyl methacrylate) (PMMA) was fabricated. Then, titanium dioxide nanoparticles (nano-TiO2s) were attached to the treated channel's interior with the aid of poly(diallyldimethylammonium chloride) (PDADMAC). After coupling the nano-TiO2-coated microfluidic-based photocatalyst-assisted reduction device (the nano-TiO2-coated microfluidic-based PCARD) with high-performance liquid chromatography (HPLC) and inductively coupled plasma mass spectrometry (ICP-MS), a selective and sensitive, hyphenated system for Hg speciation was established. Validation procedures demonstrated that the method could be satisfactorily applied to the determination of mercury ions (Hg2+) and methylmercury ions (CH3Hg+) in both human urine and water samples. Remarkably, the zeta potential measured clearly indicated that the PDADMAC-capped nano-TiO2s with a predominance of positive charges indeed provided a steady force for firm attachment to the negatively charged device channel. The cause of the durability of the nano-TiO2-coated microfluidic-based PCARD was clarified thus.

3.
Aquat Toxicol ; 274: 107045, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39142141

RESUMEN

Nano-TiO2 is inevitably released into aquatic environment with increasing of nanotechnology industries. Study pointed that different individuality showed divergent behavioral and physiological response when facing environmental stress. However, the effects of nano-TiO2 on tolerance of bivalves with different individualities remain unknown. In the study, clams were divided into two types of individuality - proactive and reactive by post-stress recovery method. It turned out that proactive individuals had quicker shell opening level, stronger burrowing behavior, faster feeding recovery, higher standard metabolic rate and more rapid ammonia excretion ability than reactive individuals after exposed to air. Then, the survival rate, hemocytes response and oxidase activity of classified clams were evaluated after nano-TiO2 exposure. Results showed that after 30 d exposure, proactive individuals accelerated burrowing behavior with higher survival rate. Moreover, proactive clams had better adaptability and less hemocytes response and oxidative damage than reactive clams. The study highlights the individualities of marine shell fish determine individual capacity to adapt to environmental changes, play important roles in aquaculture and coastal ecosystem health.


Asunto(s)
Bivalvos , Hemocitos , Titanio , Contaminantes Químicos del Agua , Animales , Titanio/toxicidad , Bivalvos/efectos de los fármacos , Hemocitos/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Estrés Oxidativo/efectos de los fármacos , Conducta Animal/efectos de los fármacos
4.
Heliyon ; 10(14): e34722, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39130420

RESUMEN

Nano-TiO2 is widely used in various fields such as industry, daily necessities, food and medicine. Previous studies have shown that it can enter mammalian tissues through the digestive tract or respiratory tract and have effects on various organs and systems. However, the effect of nano-TiO2 on the mammalian thyroid gland has not been reported. In this study, we fed SD rats with rutile nano-TiO2 at a dose of 5 mg/kg body weight for 3 weeks, and then examined the thyroid histology and thyroid function of the rats. In vitro experiments were conducted to determine the effects of nano-TiO2 on the viability, apoptosis, inflammatory factors, antioxidant enzymes, and oxidative stress of human thyroid follicular epithelial cells. Histological evidence showed abnormal morphology of rat thyroid follicles and organelle damage in follicular epithelial cells. Nano-TiO2 caused a decrease in the level of sodium/iodide symporter (NIS), an increase in the level of apoptotic protein cleaved-caspase 3, and an increase in the levels of pro-inflammatory factors IL-1ß and TNF-α in rat thyroid tissue. Nano-TiO2 also resulted in increased serum FT4 and TPO-Ab levels. In in vitro experiments, nano-TiO2 reduced the viability of human thyroid follicular cells, downregulated the levels and activities of antioxidant enzymes CAT, GPX1 and SOD, and increased the levels of ROS and MDA caused by oxidative stress. These results indicate that nano-TiO2 damages the structure and function of thyroid follicular epithelial cells through oxidative stress. Long-term exposure to nano-TiO2 could be a potential risk factor for thyroid dysfunction.

5.
Heliyon ; 10(12): e32356, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39021907

RESUMEN

Nano-TiO2 photocatalysis technology has attracted wide attention because of its safety, nontoxicity and long-lasting performance. However, traditional nano-TiO2 has been greatly limited in its application because its wide band gap can only be activated by ultraviolet light (λ < 387 nm). In this paper, nano-TiO2 was prepared by self-doping method. The synthesized nano-TiO2 was a single anatase crystal type with a particle size of 10 nm and uniform size. In addition, nano-TiO2 has high stability and good dispersion. More importantly, nano-TiO2 exhibits excellent visible light (400-780 nm) activity due to the decrease of bandgap from 3.20 eV to 1.80 eV (less than 2.0 eV) and the presence of a large number of hydroxyl groups on the surface of the nanoparticles. In the antibacterial test, the antibacterial rate of both E.coli and S.aureus was close to 100 % under the irradiation of household low-power LED lamps, showing excellent antibacterial performance, indicating that the prepared nano-TiO2 has broad application prospects in the field of bactericidal and bacteriostatic.

6.
Environ Sci Pollut Res Int ; 31(25): 37109-37124, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38760607

RESUMEN

In this study, photocatalysis technology was used to reduce water pollution. Decolorization of Reactive Black 5 using nano-TiO2 (NT) as a photocatalyst was investigated by adsorption and degradation experiments. Effects of NT particle size and utilization ratio on the time-dependent flow performance, compressive-flexural strength, and Bohme abrasion resistance of cementitious systems were investigated. In addition to the NT-free control mixture, a total of six photocatalytic self-cleaning mortar mixtures (PSCM) were prepared using NT in two different particle sizes (28 and 38 nm) and three different ratios (0.5%, 1%, and 1.5%). The PSCM sample containing 38 nm NT exhibited superior performance in terms of photocatalytic properties compared to the 28 nm state. It was observed that the flow performance of PSCM mixtures with NT substitution is adversely affected regardless of the NT type. Mixtures containing NT with a lower particle size (28 nm) had higher compressive and flexural strengths.


Asunto(s)
Titanio , Titanio/química , Catálisis , Materiales de Construcción , Tamaño de la Partícula , Adsorción
7.
J Nanobiotechnology ; 22(1): 262, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760823

RESUMEN

BACKGROUND: Nanoplastics, are emerging pollutants, present a potential hazard to food security and human health. Titanium dioxide nanoparticles (Nano-TiO2), serving as nano-fertilizer in agriculture, may be important in alleviating polystyrene nanoplastics (PSNPs) toxicity. RESULTS: Here, we performed transcriptomic, metabolomic and physiological analyzes to identify the role of Nano-TiO2 in regulating the metabolic processes in PSNPs-stressed maize seedlings (Zea mays L.). The growth inhibition by PSNPs stress was partially relieved by Nano-TiO2. Furthermore, when considering the outcomes obtained from RNA-seq, enzyme activity, and metabolite content analyses, it becomes evident that Nano-TiO2 significantly enhance carbon and nitrogen metabolism levels in plants. In comparison to plants that were not subjected to Nano-TiO2, plants exposed to Nano-TiO2 exhibited enhanced capabilities in maintaining higher rates of photosynthesis, sucrose synthesis, nitrogen assimilation, and protein synthesis under stressful conditions. Meanwhile, Nano-TiO2 alleviated the oxidative damage by modulating the antioxidant systems. Interestingly, we also found that Nano-TiO2 significantly enhanced the endogenous melatonin levels in maize seedlings. P-chlorophenylalanine (p-CPA, a melatonin synthesis inhibitor) declined Nano-TiO2-induced PSNPs tolerance. CONCLUSIONS: Taken together, our data show that melatonin is involved in Nano-TiO2-induced growth promotion in maize through the regulation of carbon and nitrogen metabolism.


Asunto(s)
Carbono , Melatonina , Nitrógeno , Poliestirenos , Titanio , Zea mays , Zea mays/efectos de los fármacos , Zea mays/metabolismo , Zea mays/crecimiento & desarrollo , Titanio/farmacología , Nitrógeno/metabolismo , Carbono/metabolismo , Melatonina/farmacología , Poliestirenos/farmacología , Plantones/efectos de los fármacos , Plantones/metabolismo , Plantones/crecimiento & desarrollo , Nanopartículas/química , Transducción de Señal/efectos de los fármacos , Fotosíntesis/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos
8.
Polymers (Basel) ; 16(4)2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38399889

RESUMEN

In this research, the influence of titanium dioxide (TiO2) nanoparticles and their modifications on the weathering resistance of untreated and heat-treated wood was studied. The wood samples were coated with polyacrylate waterborne emulsion coatings that contain nano-TiO2 in the amount of 0.75 wt.%. Two types of modifiers were used to modify the nano-TiO2 surface: 2,2'-azobis(2-methylpropionamide) dihydrochloride (AIBA) and 3-aminopropyltrimethoxy silane (AMPTS). Coated and uncoated wood samples were exposed to accelerated weathering by application of sunlight, water and moisture for 360 h. During the research, the dry film thickness, color, gloss and hardness of the surface of the samples were measured. The obtained results showed that the effect of the addition and surface modification of nano-TiO2 on the color and gloss stability was different on untreated and heat-treated ash wood, and that accelerated weathering causes an increase in surface hardness and a decrease in thickness of the dry coating.

9.
Int J Biol Macromol ; 262(Pt 2): 130138, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38354930

RESUMEN

Functional materials with under-liquid dual superlyophobicity have generated a great deal of concern from researchers due to their switchable separation ability oil-water mixtures and emulsions. Conceptually, under-liquid dual superlyophobicity is a Cassie state achievable under-liquid through the synergy of an under-liquid double lyophobic surface and the construction of a highly rough surface. However, obtaining an under-liquid dual superlyophobic surface remains difficult due to its thermodynamic contradiction and complex surface composition. Herein, we successfully prepared a functional coating by modifying the mixture of cellulose nanocrystals (CNCs) and nano-TiO2 with perfluorooctanoic acid (PFOA) via a simple method, then obtained a polyester fiber membrane with under-liquid dual superlyophobicity by roll coating method. The surface wettability of the polyester (PET) membrane was altered, transforming it from the original under-water oleophobic/under-oil superhydrophilic state to the under-water superoleophobic/under-oil superhydrophobic state after coated. The resulting membrane was applied to separate oil and water on-demand. The coated PET membrane exhibited high separation efficiency (>99 %) and high separation flux, effectively separating immiscible oil-water systems as well as oil-in-water and water-in-oil emulsions. The coated PET membrane also demonstrated the ability to perform alternate separation of oil-water mixtures through wetting, washing, and rewetting cycles, with repeated processes up to 10 times without significant reduction in separation efficiency. Furthermore, compared with the previous works, our approach offers a simpler and more convenient method for constructing under-liquid dual superlyophobic surface, making it more suitable for continuous corporate production. This study may provide inspiration for the production and application in large-scale of under-liquid dual superlyophobic membranes.


Asunto(s)
Fabaceae , Nanopartículas , Celulosa , Poliésteres , Termodinámica
10.
Chemosphere ; 352: 141445, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38354862

RESUMEN

Organic and nanoparticle pollutants are the main environmental problems affecting marine species, which have received great attention. However, the combined effect of pollutants on marine life in the presence of predators needs to be clarified. In this study, the effects of pentachlorophenol (PCP) and titanium dioxide nanoparticles (nano-TiO2) on the energy metabolism of mussels (Mytilus coruscus) in the presence of predators were assessed through cellular energy allocation (CEA) approach. Mussels were exposed to PCP (0, 1, and 10 µg/L), nano-TiO2 (1 mg/L, 25 and 100 nm), and predators (Portunus trituberculatus presence/absence) for 14 days. Exposure to high concentrations of PCP (10 µg/L) with small particle size nano-TiO2 (25 nm) decreased cellular energy stores (carbohydrates, lipids, and proteins) and increased cellular energy demand (measured as the activity of the mitochondrial electron transport system, ETS). During the first 7 days, energy was supplied mainly through the consumption of carbohydrates, while lipids are mobilized to participate after 7 days. The presence of predators caused a further decrease in energy stores. These findings demonstrate that PCP, nano-TiO2 and predators have a negative impact on energy metabolism at the cellular level. Carbohydrates are not able to meet the metabolic demand, lipids need to be consumed, and energy metabolism was also mediated by the involvement of proteins. Overall, our results suggest that PCP, nano-TiO2 and predators disrupt the cellular energy metabolism of mussels through reduced cellular energy allocation, small particles and predators drive mussels to exert energetic metabolic adjustments for detoxification reactions when toxic contaminants are present.


Asunto(s)
Contaminantes Ambientales , Mytilus , Nanopartículas , Pentaclorofenol , Contaminantes Químicos del Agua , Animales , Pentaclorofenol/metabolismo , Mytilus/metabolismo , Nanopartículas/toxicidad , Metabolismo Energético , Contaminantes Ambientales/metabolismo , Carbohidratos , Lípidos , Titanio/farmacología , Contaminantes Químicos del Agua/metabolismo
11.
Materials (Basel) ; 17(2)2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38255577

RESUMEN

The movement of the construction industry towards sustainable development has drawn attention to the revision of concrete. In addition to reducing pollution, the use of nano-materials should lead to the provision of higher quality concrete in terms of regulatory items (workability, resistance characteristics, durability characteristics, microstructure). The present study investigates 15 key characteristics of concrete modified with nano-CaCO3, nano-clay, nano-TiO2, and nano-SiO2. The results of the study showed that nanomaterials significantly have a positive effect on the hydration mechanism and the production of more C-S-H gel. The evaluation of resistance characteristics also indicates the promising results of these valuable materials. The durability characteristics of nano-containing concrete showed significant improvement despite high dispersion. Concrete in coastal areas (such as bridges or platforms), concrete exposed to radiation (such as hospitals), concrete exposed to impact load (such as nuclear power plants), and concrete containing recycled aggregate (such as bricks, tiles, ceramics) can be effectively improved by using nanomaterials. It is hoped that the current review paper can provide an effective image and idea for future applied studies by other researchers.

12.
Adv Mater ; 36(11): e2304876, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37543841

RESUMEN

Photovoltaic devices represent an efficient electricity generation mode. Integrating them into textiles offers exciting opportunities for smart electronic textiles-with the ultimate goal of supplying power for wearable technology-which is poised to change how electronic devices are designed. Many human activities occur indoors, so realizing indoor photovoltaic fibers (IPVFs) that can be woven into textiles to power wearables is critical, although currently unavailable. Here, a dye-sensitized IPVF is constructed by incorporating titanium dioxide nanoparticles into aligned nanotubes to produce close contact and stable interfaces among active layers on a curved fiber substrate, thus presenting efficient charge transport and low charge recombination in the photoanode. With the combination of highly conductive core-sheath Ti/carbon nanotube fiber as a counter electrode, the IPVF shows a certified power conversion efficiency of 25.53% under 1500 lux illuminance. Its performance variation is below 5% after bending, twisting, or pressing for 1000 cycles. These IPVFs are further integrated with fiber batteries as self-charging power textiles, which are demonstrated to effectively supply electricity for wearables, solving the power supply problem in this important direction.

13.
J Mech Behav Biomed Mater ; 148: 106201, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37866279

RESUMEN

The performance of an engineering material depends on its potentiality and characterization under different mechanical and thermal test environments. The present research study has revealed the performance of a new class of hybrid composites, focused specially on the general trends observed in their impact of fabrication and its properties. To investigate how the mechanical and thermal qualities of the epoxy matrix may be improved, pineapple leaf fibre and carbon fibre were particularly chosen. By embedding the selected filler into the Pineapple leaf Fiber/Carbon Fiber(PALF/CF) reinforced epoxy resin, coordination effects, impact of embedding were achieved in the form of modified mechanical and thermal properties. The present research work is focused to perform the thermal and mechanical properties of pineapple leaf fiber/carbon fiber reinforced epoxy resin(ER) composites with and without particulate nano TiO2 fillers. The comparison of hybrid fibre (carbon and pineapple leaf fibre) reinforced epoxy composites with and without particulate nano TiO2 fillers was done. The results of the mechanical tests demonstrated that, in comparison to all other composites, the inclusion of nano fillers improved the tensile, flexural, and impact strengths. Nano particle reinforced with hybrid composite has a score of 23.4, whereas clean epoxy only gets a score of 4.5. It follows from this example that the presence of nanoparticles raises the residual values.


Asunto(s)
Carbono , Resinas Epoxi , Fibra de Carbono , Materiales Dentales
14.
Int J Biol Macromol ; 253(Pt 3): 126966, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37729991

RESUMEN

The radioactive contamination from the excessive discharge of uranium-containing wastewater seriously threatens environmental safety and human health. Herein, macroporous and ultralight polyethyleneimine-grafted chitosan/nano-TiO2 composite foam (PCT) with antibacterial activity was synthesized, which could quickly remove U(VI) from solution. Among different PCT adsorbents, PCT-2 had the best adsorption performance for U(VI), which could be due to its honeycomb macroporous structures and the presence of abundant amino/imine groups. The kinetics and adsorption isotherms data were found in agreement with the pseudo-second-order model and the Langmuir model, respectively, indicating chemisorption or complexation as the main adsorption mechanism. The saturated adsorption capacity of PCT-2 for U(VI) reaches 259.91 mg/g at pH 5.0 and 298 K. The PCT-2 also presents good selectivity for U(VI) with the coefficient (ßU/M) order of Na+ > K+ > Mg2+ > Ca2+ > Ni2+ > Co2+ > Mn2+ > Al3+ > Fe3+ > Cu2+. The adsorption mechanism was explored using FT-IR and XPS analysis, indicating that amino/imine groups and hydroxyl groups are responsible for U(VI) complexation. Thermodynamic calculations show that U(VI) adsorption is endothermic and spontaneous. The ease of preparation, excellent adsorption performance and environmental friendliness of PCT-2 make it a novel adsorbent with antibacterial activity for radioactive contamination control.


Asunto(s)
Quitosano , Uranio , Humanos , Polietileneimina , Quitosano/química , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Adsorción , Cinética , Concentración de Iones de Hidrógeno , Uranio/química
15.
Environ Sci Pollut Res Int ; 30(42): 95537-95549, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37552440

RESUMEN

As the main components of the building envelope, construction materials have a straight relation with air contaminants from anthropogenic origins. Titanium dioxide has been recently applied in construction industry products since its photocatalytic properties can be used for pollutant degradation purposes. This study evaluated the performance of cement-based mortars with the incorporation of TiO2 nanoparticles and mineral admixtures. Six mortar compositions were defined by considering two reference mixes (with and without TiO2 incorporation), two mineral admixtures (bentonite and metakaolin) as partial cement replacement and one waste from ornamental stone processing in two levels of partial substitution of natural sand. Consistency index, density, and entrained air content of mixtures were investigated at fresh state. Compressive strength, water absorption, sorptivity, and micrographs from scanning electron microscopy were used to characterize mortars at hardened state. It was observed that incorporation of TiO2 does not considerably change mortar's properties at fresh and hardened state, despite a denser microstructure and improved interfacial transition zone. In general, the relation between the water-to-cement ratio and porosity on the performances of TiO2-added mortars was shown, which is strongly related to their photocatalytic efficiency. Metakaolin mixtures were more efficient to NO conversion, and high selectivity was observed for the bentonite mortars.


Asunto(s)
Bentonita , Titanio , Titanio/química , Minerales , Agua
16.
J Hazard Mater ; 459: 132120, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37487333

RESUMEN

Photocatalytic activation of persulfate has exhibited tremendous potential in water purification because of its green and environmentally friendly process. However, this process often exhibits low activation efficiencies and difficult recovery of the photocatalyst. Herein, schorl-supported nano-TiO2 composite photocatalysts (S/TiO2) were prepared by a mechanical grinding method for efficient activation of potassium monopersulfate (PMS). The anatase TiO2 nanoparticles with particle size of approximately 30 nm was uniformly loaded on the surface of schorl via forming Si-O-Ti bonds. The S/TiO2 assisted with PMS (S/TiO2-PMS) exhibited remarkable degradation performance and stability. In this system (S/TiO2-PMS), the C/C0 value of phenol solution (10 ppm) were decreased to 0.070 and 0 after 30 min and 90 min of irradiation, where the degradation extent were 93.0% and 100% respectively. The rate of phenol degradation with S/TiO2-PMS was 12.6 times that seen with TiO2-PMS. The oxidation active species were holes and SO4•- in S/TiO2-PMS system subjected to simulated sunlight. It was demonstrated that the polarization electric field of the schorl enhanced the separation efficiency of the photoinduced electrons and holes for improving the performance of the S/TiO2-PMS. On the other hand, the transformations of Fe3+ and Fe2+ on the schorl surface further promotes the activation of PMS. This work provides a new choice for designing TiO2-based photocatalytic persulfate activation system targeting the field of advanced oxidation water treatment.

17.
Chemosphere ; 339: 139629, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37495042

RESUMEN

Excessive utilization of antibiotics in human, animal, and aquaculture poses a substantial threat to human health and the environment. Photoelectrochemical processes are increasingly applied for water remediation because they generate oxidizing species and mineralize organic pollutants, making even small water quantities more amenable for utilization. Thus, this study presents the fabrication of an efficient nano-TiO2 photoanode thin film (PATF) specifically designed for the photoelectrocatalytic (PEC) degradation of amoxicillin (AMX). The TiO2 PATFs were deposited on fluorine-doped tin oxide (FTO) substrate using an ultrasonic spray pyrolysis process with various titanium isopropoxide (TTIP) acetylacetone (AcacH) molar ratios (1:1 to 1:10). The PEC oxidation of AMX was investigated using various molar ratios of TTIP:AcacH TiO2 PATF/FTO by linear sweep voltammetry, and a 1:8 M ratio of PATF exhibited superior PEC oxidation activity than other TiO2 PATFs. Subsequently, the PEC degradation efficiency of AMX was compared with that of photocatalytic (PC) and electrocatalytic (EC) methods. The results demonstrated that the PEC process effectively eliminated 76.2% of AMX within 120 min at 0.8 V, outperforming the removal rates attained by the EC (32.3%) and PC (52.6%). Notably, increasing the voltage to 1.0 V accelerated the PEC degradation of AMX, attaining a removal efficiency of 91.2% within 90 min and exceeding 95% within 120 min.


Asunto(s)
Amoxicilina , Titanio , Humanos , Catálisis , Agua
18.
Molecules ; 28(14)2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37513402

RESUMEN

MIL-101(Cr)@TiO2 core-shell composite material was synthesized via the hydrothermal method, where MIL-101(Cr) served as the core and TiO2 acted as the shell. SEM results revealed that the metal-organic framework core effectively prevented the aggregation of TiO2 nanoparticles and facilitated their dispersion. Characterization techniques such as XRD, XPS, and TGA were utilized to confirm the successful loading of TiO2 onto MIL-101(Cr) and its excellent thermal stability. MIL-101(Cr)@TiO2 was employed in photocatalytic degradation of dye pollutants and vehicle exhaust, and the potential degradation mechanisms were investigated in detail. The results showed that MIL-101(Cr)@TiO2 exhibited excellent photocatalytic degradation performance towards dye pollutants, with degradation efficiencies of 91.7% and 67.8% achieved for MB and RhB, respectively, under visible light irradiation for 90 min. Furthermore, the photocatalytic degradation of automobile exhaust revealed that the MIL-101(Cr)@TiO2 composite material also exhibited degradation effects on NOx, CO, and HC. The degradation efficiency for NO reached 24.2%, indicating its broader applicability.

19.
Gels ; 9(6)2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37367150

RESUMEN

With the long-term water-flooding development of the reservoir, the non-homogeneity of the formation is increasing and the reservoir environment is deteriorating; the microspheres used for deep plugging have shown disadvantages, such as poor temperature and salt resistance and faster expansion. In this study, a polymeric microsphere was synthesized that is resistant to high temperature and high salt and can achieve slow expansion and slow release for deep migration. P(AA-AM-SA)@TiO2 polymer gel/inorganic nanoparticle microspheres were prepared by reversed-phase microemulsion polymerization using acrylamide (AM) and acrylic acid (AA) as monomers, 3-methacryloxypropyltrimethoxysilane (KH-570)-modified TiO2 as the inorganic core, and sodium alginate (SA) as a temperature-sensitive coating material. Through single-factor analysis of the polymerization process, the optimal synthesis conditions were determined as follows: the oil(Cyclohexane)-water volume ratio was 8:5, the emulsifier mass ratio (Span-80:Tween-80) was 3:1 (10 wt% of the total system amount), the stirring speed was 400 r/min, the reaction temperature was 60 °C, and the initiator (ammonium persulfate and sodium bisulfite) dosage was 0.6 wt%. The size of the dried polymer gel/inorganic nanoparticle microspheres prepared by the optimized synthesis conditions was 10~40 µm with uniform particle size. The observation of P(AA-AM-SA)@TiO2 microspheres reveals that the Ca elements are uniformly distributed on the microspheres, and FT-IR indicates that the synthesized product is the target product. TGA shows that the polymer gel/inorganic nanoparticle microspheres have better thermal stability after the addition of TiO2, with a larger mass loss at 390 °C, which can adapt to the medium-high permeability reservoir environment. The thermal and aqueous salinity resistance of the P(AA-AM-SA)@TiO2 microspheres was tested, and the cracking temperature of P(AA-AM-SA)@TiO2 microsphere temperature-sensitive material was 90 °C. It still has favorable water absorption and swelling performance under the sodium salt concentration of 2.5 × 104 mg/L and can tolerate calcium salt up to 2.0 × 104 mg/L. Plugging Performance Test results show that the microspheres have good injectability between the permeability of 1.23 and 2.35 µm2 and good plugging effect near the permeability of 2.20 µm2. At high temperature and high salinity, P(AA-AM-SA)@TiO2 microspheres have a remarkable effect on profile control and water shutoff, the plugging rate reaches 95.3%, and the oil recovery rate is increased by 12.89% compared with water flooding, achieving the effect of slow swelling and slow release.

20.
Plant Physiol Biochem ; 201: 107834, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37336188

RESUMEN

In recent years, it has been found that the flavor quality of tomato is continuously reduced compared with the original tomato varieties. Studies have found that nanomaterials can improve crop quality, but the differences and related mechanisms among different nanomaterials were not reported. In this study, nano-Se, nano-TiO2 and nano-CeO2 were spraying on tomato, and the effects of the three nanomaterials on the flavor quality and physiological and antioxidant properties of fruits were analyzed and compared. The results showed compared with nano-TiO2 and nano-CeO2, nano-Se showed more obvious positive effects. Nano-Se increased the size and weight of tomato fruits and the levels of soluble sugar, promoted the accumulation of photosynthetic pigment, decreased the content of titratable acid, and also changed the expression of related genes, finally making the fruit sweeter; it also promoted the accumulation of antioxidant substances and nutrients such as lycopene, ascorbic acid, salicylic acid, GSH, SOD and CAT and decreased the content of MDA, H2O2 and OFR thus improving the antioxidant performance of fruits; the contents of volatiles were also increased and the olfactory experience of tomato was improved. Nano-TiO2 and nano-CeO2 also improved the flavor quality and antioxidant properties of tomato, but the degree was lower than nano-Se. This experiment provided references for selecting more appropriate nanomaterials to improve tomato quality, and revealed the effects and mechanisms of different nanomaterials on tomato quality.


Asunto(s)
Nanoestructuras , Solanum lycopersicum , Antioxidantes , Peróxido de Hidrógeno , Frutas
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