RESUMEN
Sonodynamic therapy depending on ultrasound irradiation, which generates reactive species to kill cancer cells, has attracted considerable attention due to the deep tissue penetration depth. However, the insufficient separation of electron/hole pairs induces its limited therapeutic efficiency. Herein, we use oxygen vacancy and ZnO quantum dots decoration techniques to enhance electron/hole separation and reactive species production. In oxygen vacancy-engineered BaTiO3, the higher oxygen vacancy concentration leads to more efficient adsorption of activate O2 and thus results in production of more radicals. In BaTiO3/ZnO heterostructures, the built-in electric field further improves separation of electron/hole pairs. The separated electron/hole react with O2/H2O to produce reactive species of â¢OH/âO2- and kill cancer cells upon ultrasound irradiation. The work provides a guidance for sonosensitizers to tumor therapy.
Asunto(s)
Compuestos de Bario , Puntos Cuánticos , Titanio , Terapia por Ultrasonido , Óxido de Zinc , Puntos Cuánticos/química , Titanio/química , Óxido de Zinc/química , Terapia por Ultrasonido/métodos , Humanos , Compuestos de Bario/química , Línea Celular Tumoral , Neoplasias/terapiaRESUMEN
Designing catalysts that can effectively make use of renewable energy benefits to solve the current challenges of environmental pollution and increasing energy demands. Piezo-photocatalysis that can utilize solar energy and natural vibration-energy has emerged as a "green" technique. In this work, we fabricated BiFeO3/C nano composites that can harvest solar and vibration energies and degrade organic pollutants. The incorporated carbon quantum dots bring about more efficient visible light absorbance and separation of photoinduced electron-hole pairs. The piezoelectric polarization further suppresses the recombination of photoinduced electron-hole pairs. The catalysts own higher reaction rates in piezo-photocatalysis and the BiFeO3/C-0.12 shows the highest degradation efficiency (k-value of 0.0835 min-1).
RESUMEN
A new combined system of ultrasound (US)/ H2O2/KI was presented in this study for the degradation of amoxicillin (AMX). Various parameters that influencing the degradation efficiency, such as ultrasonic power, pH value of the solution, concentrations of H2O2 and KI, initial concentration of AMX were investigated. The maximum degradation efficiency of 84.1% in 60â min was obtained under the optimal conditions when the ultrasonic power was 195 W, the solution pH was 3.2, the concentrations of H2O2 and KI were 120 and 2.4â mmol/L, respectively. Results also showed US/H2O2/KI system possessed better degradation efficiency compared with that by using the systems of US alone, H2O2, US/H2O2, US/KI and H2O2/KI. The degradation reaction of AMX should be a very complex process, and the corresponding degradation pathways may change at different concentrations or under different reaction conditions. The results indicate that the combined system of US/ H2O2/KI has great potential applications for the treatment of wastewater containing antibiotics with high concentrations.
RESUMEN
A large amount of ammoniacal nitrogen wastewater discharged into the water body not only causes eutrophication and black and offensive odor in water, but also increases the difficulty and cost of water treatment, and even produces toxic effects on people and organisms. In this paper, degradation of ammoniacal nitrogen wastewater by the system of ultrasound/Mg/Al2O3/ozone (US/Mg/Al2O3/O3) was carried out. The effects of different influencing factors, such as initial pH of the solution, reaction time, temperature, catalyst addition, ozone flow rate, and ultrasonic intensity, on the degradation of ammoniacal nitrogen wastewater were investigated. The optimum reaction conditions were determined. The combination of ultrasonic technology and ozone oxidation technology can enhance the mass transfer of ozone and generate a large amount of HO. Due to Mg/Al2O3 catalyst has large surface area, the number of reactive sites and reaction molecule transport channels per unit area increases, resulting in the increase of HO on the surface, thus improving the catalytic activity. The introduction of ultrasound promotes the cleavage of N-H bonds on the catalyst surface, thereby promoting the degradation of ammoniacal nitrogen in the water. Results prove that there is not only a synergistic effect between ultrasound and catalytic ozone oxidation, but a strengthening effect of ultrasound on catalytic ozone oxidation. The research carried out in this paper provides a theoretical basis for the degradation of ammoniacal nitrogen in water.
Asunto(s)
Ozono , Contaminantes Químicos del Agua , Purificación del Agua , Catálisis , Humanos , Nitrógeno , Oxidación-Reducción , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
In this work, a double-buffer film of TiOx coated with CsOx (TiOx/CsOx) was solution prepared to be applied in poly(3-hexylthiophene):indene-C60 bisadduct (P3HT:ICBA) and P3HT:[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) inverted polymer solar cells (PSCs). Compared with TiOx films and CsOx films, the TiOx/CsOx double-buffer film exhibited a favorable energy-level alignment among TiOx, CsOx, and the electron acceptor of PCBM or ICBA a better surface morphology; and an enhanced wetting and adhesion property with a contact angle of 21.0°, leading to a higher electron mobility of 5.52 × 10(-3) cm(2) V(-1)·s(-1). Moreover, the P3HT:ICBA and P3HT:PCBM photovoltaic devices with the double-buffer film showed the best power conversion efficiency up to 5.65% and 3.76%, respectively. Our results not only present that the double-buffer film is superior than the single film of TiOx and CsOx, but also imply that the solution-processed film has a potential to be generally used in roll-to-roll processed organic photovoltaic devices.
RESUMEN
To develop biodegradable polymers with temperature-sensitivity, a series of polyurethanes consisting of poly (ethylene glycol) (PEG) and L-lysine ester diisocyanate (LDI) were synthesized, and the structure and molecule weight of the polymers were examined by (1)H NMR, FT-IR, gel permeation chromatography (GPC). The solution properties of the copolymers were studied by turbidity measurement and size measurement. Polyurethanes could form nanoparticles by sonication in water. No temperature-sensitivity was observed with the polyurethane nanoparticles composed of PEG1000 and PEG1500. On the contrary, LDI-PEG600 exhibited a reversible temperature-responsive behavior in aqueous solution. The transition temperature (T(c)) of LDI-PEG600 with methyl ester of LDI was higher than that of LDI-PEG600 with butyl ester side chain. The polymers were then used to encapsulate adriamycin (ADR) by the dialyzing method from dimethylformamide solution against water. ADR could be successfully encapsulated into the polyurethane nanoparticles. The ratio of ADR release from polymeric nanoparticles increased sharply above the T(c), while the release was suppressed below the T(c).