Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 57
Filtrar
1.
Medicina (Kaunas) ; 60(6)2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38929493

RESUMEN

A ganglion cyst is a benign mass consisting of high-viscosity mucinous fluid. It can originate from the sheath of a tendon, peripheral nerve, or joint capsule. Compressive neuropathy caused by a ganglion cyst is rarely reported, with the majority of documented cases involving peroneal nerve palsy. To date, cases demonstrating both peroneal and tibial nerve palsies resulting from a ganglion cyst forming on a branch of the sciatic nerve have not been reported. In this paper, we present the case of a 74-year-old man visiting an outpatient clinic complaining of left-sided foot drop and sensory loss in the lower extremity, a lack of strength in his left leg, and a decrease in sensation in the leg for the past month without any history of trauma. Ankle dorsiflexion and great toe extension strength on the left side were Grade I. Ankle plantar flexion and great toe flexion were Grade II. We suspected peroneal and tibial nerve palsy and performed a screening ultrasound, which is inexpensive and rapid. In the operative field, several cysts were discovered, originating at the site where the sciatic nerve splits into peroneal and tibial nerves. After successful surgical decompression and a series of rehabilitation procedures, the patient's neurological symptoms improved. There was no recurrence.


Asunto(s)
Ganglión , Neuropatías Peroneas , Humanos , Anciano , Masculino , Ganglión/complicaciones , Ganglión/cirugía , Neuropatías Peroneas/etiología , Neuropatías Peroneas/fisiopatología , Nervio Peroneo/fisiopatología , Nervio Tibial/fisiopatología , Parálisis/etiología , Parálisis/fisiopatología
2.
Int J Mol Sci ; 24(11)2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37298619

RESUMEN

Acne is a common skin condition caused by the growth of certain bacteria. Many plant extracts have been investigated for their potential to combat acne-inducing microbes, and one such plant extract is microwave-assisted Opuntia humifusa extract (MA-OHE). The MA-OHE was loaded onto zinc-aminoclay (ZnAC) and encapsulated in a Pickering emulsion system (MA-OHE/ZnAC PE) to evaluate its therapeutic potential against acne-inducing microbes. Dynamic light scattering and scanning electron microscopy were used to characterize MA-OHE/ZnAC PE with a mean particle diameter of 353.97 nm and a PDI of 0.629. The antimicrobial effect of MA-OHE/ZnAC was evaluated against Staphylococcus aureus (S. aureus) and Cutibacterium acnes (C. acnes), which contribute to acne inflammation. The antibacterial activity of MA-OHE/ZnAC was 0.1 and 0.025 mg/mL to S. aureus and C. acnes, respectively, which were close to naturally derived antibiotics. Additionally, the cytotoxicity of MA-OHE, ZnAC, and MA-OHE/ZnAC was tested, and the results showed that they had no cytotoxic effects on cultured human keratinocytes in a range of 10-100 µg/mL. Thus, MA-OHE/ZnAC is suggested to be a promising antimicrobial agent for treating acne-inducing microbes, while MA-OHE/ZnAC PE is a potentially advantageous dermal delivery system.


Asunto(s)
Acné Vulgar , Staphylococcus aureus , Humanos , Emulsiones/uso terapéutico , Zinc/farmacología , Zinc/uso terapéutico , Acné Vulgar/tratamiento farmacológico , Acné Vulgar/microbiología , Queratinocitos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Propionibacterium acnes
3.
Nano Lett ; 21(18): 7879-7886, 2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34328342

RESUMEN

Artificial synaptic platforms are promising for next-generation semiconductor computing devices; however, state-of-the-art optoelectronic approaches remain challenging, owing to their unstable charge trap states and limited integration. We demonstrate wide-band-gap (WBG) III-V materials for photoelectronic neural networks. Our experimental analysis shows that the enhanced crystallinity of WBG synapses promotes better synaptic characteristics, such as effective multilevel states, a wider dynamic range, and linearity, allowing the better power consumption, training, and recognition accuracy of artificial neural networks. Furthermore, light-frequency-dependent memory characteristics suggest that artificial optoelectronic synapses with improved crystallinity support the transition from short-term potentiation to long-term potentiation, implying a clear emulation of the psychological multistorage model. This is attributed to the charge trapping in deep-level states and suppresses fast decay and nonradiative recombination in shallow traps. We believe that the fingerprints of these WBG synaptic characteristics provide an effective strategy for establishing an artificial optoelectronic synaptic architecture for innovative neuromorphic computing.


Asunto(s)
Redes Neurales de la Computación , Sinapsis , Fotones
4.
Sensors (Basel) ; 20(1)2020 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-31947903

RESUMEN

Laser lights have been used by dermatologists for tattoo removal through photothermal interactions. However, most clinical studies used a visual scoring method to evaluate the tattoo removal process less objectively, leading to unnecessary treatments. This study aimed to develop a simple and quantitative imaging method to monitor the degree of tattoo removal in in vivo skin models. Sprague Dawley rat models were tattooed with four different concentrations of black inks. Laser treatment was performed weekly on the tattoos using a wavelength of 755 nm over six weeks. Images of non-treated and treated samples were captured using the same method after each treatment. The intensities of the tattoos were measured to estimate the contrast for quantitative comparison. The results demonstrated that the proposed monitoring method quantified the variations in tattoo contrast after the laser treatment. Histological analysis validated the significant removal of tattoo inks, no thermal injury to adjacent tissue, and uniform remodeling of epidermal and dermal layers after multiple treatments. This study demonstrated the potential of the quantitative monitoring technique in assessing the degree of clearance level objectively during laser treatments in clinics.


Asunto(s)
Procedimientos Quirúrgicos Dermatologicos/métodos , Epidermis/cirugía , Terapia por Láser/métodos , Tatuaje/efectos adversos , Animales , Modelos Animales de Enfermedad , Epidermis/patología , Humanos , Ratas , Piel/patología
5.
Nanotechnology ; 30(23): 235301, 2019 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-30769339

RESUMEN

One-dimensional (1D) and three-dimensional (3D) residue-free metal oxide patterns are directly fabricated over large areas using liquid transfer imprint lithography (LTIL) with an ultraviolet-curable metal oxide precursor resist. A 1D line or pillar array of metal oxides nano-patterns without a residual layer is formed by LTIL and annealing processes. A 3D layer-by-layer nanomesh structure is successfully constructed by repeating the LTIL method without a complex etching process. In addition, it is possible to form a hierarchical structure in which zinc oxide nanowires are selectively grown on a desired zinc oxide (ZnO) seed pattern formed by LTIL via a hydrothermal method. Unlike the pattern fabricated by the conventional nanoimprint lithography method, in the case of the pattern formed by LTIL the residues accumulated between the patterns during the patterning procedure can be removed, and thus it is possible to easily form various types of nanostructures.

6.
J Nanosci Nanotechnol ; 19(3): 1269-1275, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30469174

RESUMEN

Icing of railway contact wires in the cold climates of the USA, Canada, China, Japan, and South Korea can cause significant problems and delays in the operation schedules of electric-powered trains and subway cars. As anti-icing methods, manual de-icing, contact-wire thermal running, resistive-wire-heating de-icing, and chemical de-icing have all been explored and tested. Among them, environmentally friendly chemical de-icing based on the same concept as that of automobileengine antifreezer can be practically effective for application to contact wires at railcar depots. In the present study, the railway contact wires are coated with anti-icing mixtures of ethylene glycol/tap water and glycerol/tap water at various ratios (v/v %) as well as with tap water alone, at temperatures of -30 and -40 °C in a deep freezer. The morphological change on the wire surfaces is observed under optical microscopy. The surface-contact angles are measured to examine the surface difference between uncoated and coated railway contact-wire fragments. Conclusively, the fragments coated with 40/60 and 60/40 (v/v %) ratios of ethylene glycol or glycerol with tap water, as compared with the uncoated fragments, are shown to have been effectively de-iced. The surface-characterizations data thus indicate that mixtures of glycerol or ethylene glycol with tap water can be practical de-icing agents for application to railway contact wires.

7.
Small ; 12(2): 214-9, 2016 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-26584654

RESUMEN

Recently, the appeal of 2D black phosphorus (BP) has been rising due to its unique optical and electronic properties with a tunable band gap (≈0.3-1.5 eV). While numerous research efforts have recently been devoted to nano- and optoelectronic applications of BP, no attention has been paid to promising medical applications. In this article, the preparation of BP-nanodots of a few nm to <20 nm with an average diameter of ≈10 nm and height of ≈8.7 nm is reported by a modified ultrasonication-assisted solution method. Stable formation of nontoxic phosphates and phosphonates from BP crystals with exposure in water or air is observed. As for the BP-nanodot crystals' stability (ionization and persistence of fluorescent intensity) in aqueous solution, after 10 d, ≈80% at 1.5 mg mL(-1) are degraded (i.e., ionized) in phosphate buffered saline. They showed no or little cytotoxic cell-viability effects in vitro involving blue- and green-fluorescence cell imaging. Thus, BP-nanodots can be considered a promising agent for drug delivery or cellular tracking systems.


Asunto(s)
Tecnología Biomédica/métodos , Nanopartículas/química , Fósforo/química , Animales , Materiales Biocompatibles/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Fluorescencia , Humanos , Microscopía de Fuerza Atómica , Fenómenos Ópticos , Espectrometría Raman , Difracción de Rayos X
8.
J Nanosci Nanotechnol ; 16(2): 1392-5, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27433592

RESUMEN

Biocompatible Mg- and Fe-aminoclays (MgAC and FeAC)-decorated polyacrylonitrile (PAN) nano-fibers (NFs, diameter range: 190-380 nm) are prepared by the electrospinning process. There is a large increase in the biomolecular activities of the PAN NFs that were oxygen plasma (OP)-treated (the OPNFs) relative to those of the pristine PAN NFs, due to the OP treatment's carboxylation and/or hydroxylation of the PAN NF surfaces. With morphological observation by scanning electron microscopy (SEM), and following further confirmation of the Fourier-transform infrared (FI-IR) spectra of the as-prepared AC-OPNFs, human neural stem cell (NSC) self-renewal is tested, focusing on the relevant discrepancies among the AC-OPNFs, OPNFs, and pristine PAN NFs as flexible cellular matrices. Interestingly, NSCs are attached well on four NFs without conventional coating materials. Self-renewal of NSCs is confirmed by marker expressions such as PAX6 and N-CADHERIN. Among four NFs, FeAC-OPNFs shows the best property of NSC self-renewal. It is expected that AC-OPNFs can be xeno-free and protein-free extracellular matrices for supporting human NSC self-renewal.


Asunto(s)
Silicatos de Aluminio/química , Proliferación Celular , Nanofibras/química , Células-Madre Neurales/metabolismo , Gases em Plasma , Línea Celular , Arcilla , Humanos , Células-Madre Neurales/citología
9.
J Nanobiotechnology ; 13: 88, 2015 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-26612177

RESUMEN

We have investigated the cytotoxic assay of Fe-aminoclay (FeAC) nanoparticles (NPs) and simultaneous imaging in HeLa cells by photoluminescent carbon nanodots (CD) conjugation. Non-cytotoxic, photostable, and CD NPs are conjugated with cationic FeAC NPs where CD NPs play a role in bio-imaging and FeAC NPs act as a substrate for CD conjugation and help to uptake of NPs into cancer cells due to positively charged surface of FeAC NPs in physiological media. As increase of CD-FeAC NPs loading in HeLa cell in vitro, it showed slight cytotoxicity at 1000 µg/mL but no cytotoxicity for normal cells up to concentration of 1000 µg/mL confirmed by two 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and neutral red (NR) assays, with further observations by 4',6-diamidino-2-phenylindole (DAPI) stained confocal microscopy images, possessing that CD-FeAC NPs can be used as potential drug delivery platforms in cancer cells with simultaneous imaging. Graphical abstract CD conjugation with organo-building blocks of delaminated FeAC NPs.


Asunto(s)
Carbono/química , Imagenología Tridimensional/métodos , Compuestos de Hierro/química , Hierro/química , Nanopartículas/química , Silicatos/química , Animales , Muerte Celular , Supervivencia Celular , Endocitosis , Células HeLa , Humanos , Hidrodinámica , Indoles/metabolismo , Ratones , Microscopía Confocal , Nanopartículas/ultraestructura , Tamaño de la Partícula , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Difracción de Rayos X
10.
J Nanosci Nanotechnol ; 14(11): 8699-702, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25958587

RESUMEN

The design of DNA nanostructures is of fundamental importance, the intrinsic value of DNA as a building-block material lies in its ability to organize other bio-molecules with nanometer-scale spacing. Here, we report the fabrication of DNA scaffolds with nano-pores (< 10 nm size) that formed easily without the use of additives (i.e., avidin, biotin, polyamine, or inorganic materials) into large scale DNA nanostructures by controlling buffer pH and reaction temperature. Large scale DNA scaffolds with porous structures are stable and uniform at slightly acidic buffer pH values (pH 5.5) and at approximately room temperature (- 30 degrees C). The depth of the DNA scaffolds with randomly porous size (< 10 nm) was a maximum of approximately 8 nm. Protein immobilization results also confirmed that a fibronectin (FN) proteins/large scale DNA scaffolds/aminopropylytriethoxysilane (APS)/SiO2/Si substrate with high sensitivity formed in a well-defined manner. The DNA scaffolds can be applied for use with DNA based biochips, biophysics, and cell biology.


Asunto(s)
ADN/química , Proteínas Inmovilizadas/química , Microscopía de Fuerza Atómica/métodos , Nanoestructuras/química , Nanotecnología/métodos , Adsorción , Biotecnología , Nanoporos , Porosidad , Temperatura
11.
Ecotoxicol Environ Saf ; 102: 34-41, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24580819

RESUMEN

In the present study the short term aquatic ecotoxicity of water-solubilized aminoclay nanoparticles (ANPs) of ~51±31 nm average hydrodynamic diameter was characterized. An ecotoxicological evaluation was carried out utilizing standard test organisms of different phyla and trophic levels namely the eukaryotic microalga Pseudokirchneriella subcapitata, the crustacean Daphnia magna and the bioluminescent marine bacteria Vibrio fisheri. The effective inhibitory concentration (EC50) with 95% confidence limits for the microalga was 1.29 mg/L (0.72-1.82) for the average growth rate and 0.26 mg/L (0.23-0.31) for the cell yield. The entrapping of algal cells in aggregates of ANP may play a major role in the growth inhibition of algae P. subcapitata. No inhibition was observed for V. fisheri up to 25,000 mg/L (no observed effect concentration; NOEC). For D. magna no immobilization was observed in a limit test with 100 mg/L in 24 h while in 48 h a single animal was immobilized (5% inhibition). Correspondingly, the NOEC of ANP in 24 h was 100 mg/L and the lowest observed effect concentration (LOEC) for 48 h was 100 mg/L. Therefore it can be considered to use ANP as an algal-inhibition agent at concentrations <100 mg/L without affecting or only mildly affecting other organisms including zooplanktons, but further studies on the environmental fate and chronic toxicity of ANP is needed to confirm this.


Asunto(s)
Aliivibrio fischeri/efectos de los fármacos , Chlorophyta/efectos de los fármacos , Daphnia/efectos de los fármacos , Ecotoxicología , Nanopartículas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Daphnia/crecimiento & desarrollo , Concentración 50 Inhibidora , Agua/química
12.
Bioprocess Biosyst Eng ; 37(10): 2083-94, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24719225

RESUMEN

Flue gases mainly consist of CO2 that can be utilized to facilitate microalgal culture for bioenergy production. In the present study, to evaluate the feasibility of the utilization of flue gas from a coal-burning power plant, an indigenous and high-CO2-tolerant oleaginous microalga, Chlorella sp. KR-1, was cultivated under mixotrophic conditions, and the results were evaluated. When the culture was mediated by flue gas, highest biomass (0.8 g cells/L·d) and FAME (fatty acid methyl esters) productivity (121 mg/L·d) were achieved in the mixotrophic mode with 5 g/L glucose, 5 mM nitrate, and a flow rate of 0.2 vvm. By contrast, the photoautotrophic cultivation resulted in a lower biomass (0.45 g cells/L·d) and a lower FAME productivity (60.2 mg/L·d). In general, the fatty acid profiles of Chlorella sp. KR-1 revealed meaningful contents (>40 % of saturated and mono-unsaturated fatty acids) under the mixotrophic condition, which enables the obtainment of a better quality of biodiesel than is possible under the autotrophic condition. Conclusively then, it was established that a microalgal culture mediated by flue gas can be improved by adoption of mixotrophic cultivation systems.


Asunto(s)
Biocombustibles , Chlorella/metabolismo , Carbón Mineral , Gases , Reactores Biológicos , Chlorella/crecimiento & desarrollo
13.
Materials (Basel) ; 17(11)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38893937

RESUMEN

In this study, the effect of atmospheric hydrogen plasma treatment on the in-plane conductivity of solution-processed zinc oxide (ZnO) in various environments is reported. The hydrogen-plasma-treated and untreated ZnO films exhibited ohmic behavior with room-temperature in-plane conductivity in a vacuum. When the untreated ZnO film was exposed to a dry oxygen environment, the conductivity rapidly decreased, and an oscillating current was observed. In certain cases, the thin film reversibly 'switched' between the high- and low-conductivity states. In contrast, the conductivity of the hydrogen-plasma-treated ZnO film remained nearly constant under different ambient conditions. We infer that hydrogen acts as a shallow donor, increasing the carrier concentration and generating oxygen vacancies by eliminating the surface contamination layer. Hence, atmospheric hydrogen plasma treatment could play a crucial role in stabilizing the conductivity of ZnO films.

14.
Biomed Pharmacother ; 177: 117001, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38936194

RESUMEN

BACKGROUND: 1,25(OH)2D3 is a fat-soluble vitamin, involved in regulating Ca2+ homeostasis in the body. Its storage in adipose tissue depends on the fat content of the body. Obesity is the result of abnormal lipid deposition due to the prolonged positive energy balance and increases the risk of several cancer types. Furthermore, it has been associated with vitamin D deficiency and defined as a low 25(OH)2D3 blood level. In addition, 1,25(OH)2D3 plays vital roles in Ca2+-Pi and glucose metabolism in the adipocytes of obese individuals and regulates the expressions of adipogenesis-associated genes in mature adipocytes. SCOPE AND APPROACH: The present contribution focused on the VDR mediated mechanisms interconnecting the obese condition and cancer proliferation due to 1,25(OH)2D3-deficiency in humans. This contribution also summarizes the identification and development of molecular targets for VDR-targeted drug discovery. KEY FINDINGS AND CONCLUSIONS: Several studies have revealed that cancer development in a background of 1,25(OH)2D3 deficient obesity involves the VDR gene. Moreover, 1,25(OH)2D3 is also known to influence several cellular processes, including differentiation, proliferation, and adhesion. The multifaceted physiology of obesity has improved our understanding of the cancer therapeutic targets. However, currently available anti-cancer drugs are notorious for their side effects, which have raised safety issues. Thus, there is interest in developing 1,25(OH)2D3-based therapies without any side effects.


Asunto(s)
Neoplasias , Obesidad , Receptores de Calcitriol , Vitamina D , Humanos , Receptores de Calcitriol/metabolismo , Receptores de Calcitriol/genética , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Animales , Vitamina D/uso terapéutico , Vitamina D/metabolismo , Vitamina D/farmacología , Deficiencia de Vitamina D/tratamiento farmacológico , Deficiencia de Vitamina D/complicaciones , Terapia Molecular Dirigida
15.
Chemosphere ; 355: 141859, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38561161

RESUMEN

To promptly and simply create highly crystalline S/C co-doped TiO2 (SC-TiO2) photocatalysts at room temperature and atmospheric pressure, we suggest a novel plasma-assisted sol-gel synthesis method. This method is a simultaneous synthetic process, in which an underwater plasma undergoes continuous reactions to generate high-energy atomic and molecular species that enable TiO2 to achieve crystallinity, a large surface area, and a heterogeneous structure within a few minutes. In particular, it was demonstrated that the heterogeneously structured TiO2 was formed by doping that sulfur and carbon replace O or Ti atoms in the TiO2 lattice depending on the composition of the synthesis solution during underwater plasma treatment. The resultant SC-TiO2 photocatalysts had narrowed bandgap energies and extended optical absorption scope into the visible range by inducing the intermediate states within bandgap due to generation of oxygen vacancies on the surface of TiO2 through synthesis, crystallization, and doping. Correspondingly, SC-TiO2 showed a significant degradation efficiency ([k] = 6.91 h-1) of tetracycline (TC, antibiotics) under solar light irradiation, up to approximately 4 times higher compared to commercial TiO2 ([k] = 1.68 h-1), resulting in great water purification. Therefore, we anticipate that this underwater discharge plasma system will prove to be an advantageous technique for producing heterostructural TiO2 photocatalysts with superior photocatalytic efficiency for environmental applications.


Asunto(s)
Carbono , Luz , Carbono/química , Antibacterianos , Tetraciclina , Azufre , Titanio/química , Catálisis
16.
Ultrason Sonochem ; 100: 106623, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37832252

RESUMEN

Designing a heterostructure nanoscale catalytic site to facilitate N2 adsorption and photogenerated electron transfer would maximize the potential for photocatalytic activity and N2 reduction reactions. Herein, we have explored the interfacial TiO2 nanograins between the Ti3C2TxMXene-WS2 heterostructure and addressed the beneficial active sites to expand the effective charge transfer rate and promote sonophotocatalytic N2 fixation. Benefiting from the interfacial contact and dual heterostructure interface maximizes the photogenerated carrier separation between WS2 and MXene/TiO2. The sonophotocatalytic activity of the MXene@TiO2/WS2 hybrid, which was assessed by examining the photoreduction of N2 with ultrasonic irradiation, was much higher than that of either sonocatalytic and photocatalytic activity because of the synergistic sonocatalytic effect under photoirradiation. The Schottky junction between the MXene and TiO2 on the hybrid MXene/TiO2-WS2 heterostructure resulted in the sonophotocatalytic performance through effective charge transfer, which is 1.47 and 1.24 times greater than MXene-WS2 for nitrogen fixation and pollutant degradation, respectively. Under the sonophotocatalytic process, the MXene/TiO2-WS2 heterostructure exhibits a decomposition efficiency of 98.9 % over tetracycline in 90 min, which is 5.46, 1.73, and 1.10 times greater than those of sonolysis, sonocatalysis, and photocatalysis, respectively. The production rate of NH3 on MXene/TiO2-WS2 reached 526 µmol g-1h-1, which is 3.17, 3.61, and 1.47 times higher than that of MXene, WS2, and MXene-WS2, respectively. The hybridized structure of MXene-WS2 with interfacial surface oxidized TiO2 nanograins minimizes the band potential and improves photocarrier use efficiency, contributing directly to the remarkable catalytic performance towards N2 photo fixation under visible irradiation under ultrasonic irradiation. This report provides the strategic outcome for the mass carrier transfer rate and reveals a high conversion efficiency in the hybridized heterostructure.

17.
J Colloid Interface Sci ; 650(Pt A): 752-763, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37441968

RESUMEN

In this work, we initially prepared layered lithium titanate (Li2TiO3) using a solid-state reaction. Then Li+ of Li2TiO3 were acid-eluded with Hydrochloric acid to obtain hydrated titanium oxide (H2TiO3). Different weight percentages (50%, 60%, 70%, 80%, and 90%) of the as-prepared H2TiO3 were deposited on a conductive reduced graphene oxide (rGO) matrix to obtain a series of rGO/ H2TiO3 composites. Of the prepared composites, rGO/H2TiO3-60% showed excellent current density, high specific capacitance, and rapid ion diffusion. An asymmetric MCDI (membrane capacitive deionization) cell fabricated with activated carbon as the anode and rGO/H2TiO3-60% as the cathode displayed outstanding Li+ electrosorption capacity (13.67 mg g-1) with a mean removal rate of 0.40 mg g-1 min-1 in a 10 mM LiCl aqueous solution at 1.8 V. More importantly, the rGO/H2TiO3-60% composite electrode exhibited exceptional Li+ selectivity, superior cyclic stability up to 100,000 s, and a Li+ sorption capacity retention of 96.32% after 50 adsorption/desorption cycles. The excellent Li+ extraction obtained by MCDI using the rGO/H2TiO3-60% negative electrode was putatively attributed to: (i) ion exchange between Li+ and H+ of H2TiO3; (ii) the presence of narrow lattice spaces in H2TiO3 suitable for selective Li+ capture; (iii) capture of Li+ by isolated and hydrogen-bonded hydroxyl groups of H2TiO3; and (iv) enhanced interfacial contact and transfer of large numbers of Li+ ions from the electrolyte to H2TiO3 achieved by compositing H2TiO3 with a highly conductive rGO matrix.

18.
J Nanosci Nanotechnol ; 12(7): 6022-5, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22966701

RESUMEN

Atmospheric plasma (AP) treatment was carried out on TiO2 nanorods (NRs) that were hydrothermally grown on F-doped SnO2 (FTO)/glass. The effects of AP treatment on the surface of the TiO2 NRs were investigated, where the treatment involved the use of the reactive gases H2, N2, and O2. The surface energy of AP-treated TiO2 NRs was about 1.5 times higher than that of untreated TiO2 NRs (364.3 mJ/m2). After AP treatment, the increase of the peak area ratios of the Ti2O3 and TiO2 peaks in the XPS spectra resulted in a decrease in the number of oxygen vacancies in the TiO2 NRs. The efficiency of a dye-sensitized solar cell (DSSC) based on the N2-plasma-treated TiO2 NRs, which was approximately 1.11%, was about 79% higher than that of a DSSC based on the untreated TiO2 NRs.

19.
Chemosphere ; 287(Pt 2): 132204, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34826909

RESUMEN

We identified optimal conditions for the disposal of high concentration of organic contaminants within a short time using a hybrid advanced oxidation process (AOP) combining various oxidizing agents. Plasma-treated water (PTW) containing many active species, that play dominant roles in the degradation of organic substances like hydroxyl radicals, atomic oxygen, ozone, and hydrogen peroxide, was used in this study as a strategy to improve degradation performance without the use of expensive chemical reagents like hydrogen peroxide. In particular, the optimal decomposition conditions using PTW, which were combined with 10 mg/h ozone, 2 g/L iron oxide, and 4 W UV light, demonstrated excellent removal abilities of a high concentration of reactive black 5 (RB5; 100 mg/L, >99%, [k] = 4.15 h-1) and tetracycline (TC; 10 mg/L, >96.5%, [k] = 3.35 h-1) for 25 min, approximately 1.5 times higher than that without PTW (RB5; 100 mg/L, 94%, [k] = 2.80 h-1). These results confirmed that the production of strong reactive hydroxyl radicals from the decomposition process, as well as various reactive species included in PTW efficiently attacked pollutant substances, resulting in a higher removal rate. This suggests that a water treatment system with this optimal condition based on complex AOP systems using PTW could be useful in critical environmental and biomedical applications.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Peróxido de Hidrógeno , Oxidación-Reducción , Rayos Ultravioleta , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/análisis
20.
J Nanosci Nanotechnol ; 11(8): 7155-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22103146

RESUMEN

TiO2 nanobarbed fiber (NBF) structures consisting of TiO2 nanorods (NRs) on TiO2 nanofibers (NFs) were fabricated. The mean length and diameter of the TiO2 NRs grown for 6 h was 1.38 microm and 71 nm, respectively. One NR was connected to other NRs and the junction points between the TiO2 NRs increased with increasing TiO2 NR length. The crystal structure of the TiO2 NFs and NRs was rutile and anatase, respectively. After post-annealing, only the intensity of the TiO2 NBF peaks increased without any significant structural changes. Raman spectroscopy showed that the TiO2 NBF structure consisted of anatase (TiO2 NFs) and rutile (TiO2 NRs). The bandgap of the TiO2 NBF structure prepared during a TiO2 NR growth time from 0 to 6 h decreased from 3.23 eV to 3.10 eV. The conductivity of the TiO2 NBFs with longer NRs was enhanced by post-annealing.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA