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All pesticides are toxic by nature and pose short- or long-term safety risks to human or the environment, especially when they were used extensively and absence of safety measures. As a new insecticidal active compound with a novel mechanism of action, there is a serious inadequate of information on the hydrolytic behavior of broflanilide in the aqueous environment, as well as its degradation pattern in agricultural soils. In particular, the effects of temperature and pH of the aqueous environment on its hydrolytic behaviors and the dissipation pattern in different types of agricultural soils were still in a dark box. And the further understanding and insights into this insecticidal active ingredient were being deeply conditioned by these doubts. The hydrolysis behavior of broflanilide and the dissipation pattern in soil were systematically investigated by constructing hydrolysis systems with different temperatures and pH values, and conducting spiking experiments in different types of agricultural soil in the laboratory. The obtained results showed that the longest hydrolysis half-life of 10 mg/L broflanilide at 25 °C was 43.32 h (in pH 4.0 buffer), while it was only 12.84 h in pH 9.0 buffer. In pH 7.0 buffer, the hydrolysis rate of broflanilide exhibited a significant temperature dependence, as shown by the fact that for every 10 °C increase in the system temperature, the corresponding hydrolysis rate will increase about 1.5 times. The dissipation experiments in soils showed that broflanilide was most rapidly dissipated in fluvo-aquic soil (half-life of 1.94 days), followed by lime concretion black soil (half-life of 2.53 days) and cinnamon soil (half-life of 3.11 days), and slower in paddy soil (half-life of 4.03 days). It was indicated that broflanilide was a readily degradable pesticide in both aqueous environment and agricultural soil, and it was significantly affected by the temperature and pH of the system.
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Inseticidas , Praguicidas , Poluentes do Solo , Humanos , Solo/química , Hidrólise , Agricultura , Água , Poluentes do Solo/análiseRESUMO
LED light bulbs that simulate solar spectrum were fabricated using CdSe core-shell quantum dots in combination with GaN blue-light chips. They exhibited excellent optical properties such as white CIE coordinates of (0.33, 0.33), high color rendering index (CRI) of 98 and correlated color temperature (CCT) of 5352 K. Moreover, a circuit system was used to control the LEDs so that the lighting spectrum changes with the time in a day to simulate the actual solar spectrum. The results show that the sun-like spectrum smart bulbs not only have good optical properties and high electrical stability, but also can automatically adjust their spectrum according to the time, making the lighting natural. This work makes sun-like lighting conditions for some special environments to promote the application of smart bulbs in smart lighting.
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The extracellular matrix (ECM) is the naturally occurring substrate that provides a support structure and an attachment site for cells. It also produces a biological signal, which plays an important role in and has significant impact on cell adhesion, migration, proliferation, differentiation, and gene expression. Peripheral nerve repair is a complicated process involving Schwann cell proliferation and migration, 'bands of Büngner' formation, and newborn nerve extension. In the ECM of peripheral nerves, macromolecules are deposited among cells; these constitute the microenvironment of Schwann cell growth. Such macromolecules include collagen (I, III, IV, V), laminin, fibronectin, chondroitin sulfate proteoglycans (CSPGs), and other nerve factors. Collagen, the main component of ECM, provides structural support and guides newborn neurofilament extension. Laminin, fibronectin, CSPGs, and neurotrophic factors, are promoters or inhibitors, playing different roles in nerve repair after injury. By a chemical decellularization process, acellular nerve allografting eliminates the antigens responsible for allograft rejection and maintains most of the ECM components, which can effectively guide and enhance nerve regeneration. Thus, the composition and features of peripheral nerve ECM suggest its superiority as nerve repair material. This review focuses on the structure, function, and application in the tissue engineering nerve construction of the peripheral nerve ECM components.
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Matriz Extracelular/metabolismo , Regeneração Nervosa/fisiologia , Nervos Periféricos/metabolismo , Engenharia Tecidual/métodos , Animais , Humanos , Traumatismos dos Nervos Periféricos/terapiaRESUMO
0D perovskites have gained much attention in recent years due to their fascinating properties derived from their peculiar structure with isolated metal halide octahedra or metal halide clusters. However, the systematic discussion on the crystal and electronic structure of 0D perovskites to further understand their photophysical characteristics and the comprehensive overview of 0D perovskites for their further applications are still lacking. In this review, the unique crystal and electronic structure of 0D perovskites and their diverse properties are comprehensively analyzed, including large bandgaps, high exciton binding energy, and largely Stokes-shifted broadband emissions from self-trapped excitons. Furthermore, the photoluminescence regulation are discussed. Then, the various synthetic methods for 0D perovskite single crystals, nanocrystals, and thin films are comprehensively summarized. Finally, the emerging applications of 0D perovskites to light-emitting diodes, solar cells, detectors, and some others are illustrated, and the outlook on future research in the field is also provided.
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Lead-based halide perovskites have received great attention in light-emitting applications due to their excellent properties, including high photoluminescence quantum yield (PLQY), tunable emission wavelength, and facile solution preparation. In spite of excellent characteristics, the presence of toxic element lead directly obstructs their further commercial development. Hence, exploiting lead-free halide perovskite materials with superior properties is urgent and necessary. In this review, the deep-seated reasons that benefit light emission for halide perovskites, which help to develop lead-free halide perovskites with excellent performance, are first emphasized. Recent advances in lead-free halide perovskite materials (single crystals, thin films, and nanocrystals with different dimensionalities) from synthesis, crystal structures, optical and optoelectronic properties to applications are then systematically summarized. In particular, phosphor-converted LEDs and electroluminescent LEDs using lead-free halide perovskites are fully examined. Ultimately, based on current development of lead-free halide perovskites, the future directions of lead-free halide perovskites in terms of materials and light-emitting devices are discussed.
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2D transition metal carbides, nitrides, and carbonitrides called MXenes show outstanding performance in many applications due to their superior physical and chemical properties. Herein, a ZnO-MXene mixture with different contents of Ti3 C2 is applied as electron transport layers (ETLs) and the influence of the Ti3 C2 MXene in all-inorganic metal halide perovskite nanocrystal light-emitting diodes (perovskite NC LEDs) is explored. The addition of Ti3 C2 makes more balanced charge carrier transport in LEDs by changing the energy level structure and electron mobility of ETL. Moreover, lower surface roughness is obtained for the ETL, thus guaranteeing uniform distribution of the perovskite NCs layer and further reducing leakage current. As a result, a 17.4% external quantum efficiency (EQE) with low efficiency roll-off is achieved with 10% Ti3 C2 , which is a 22.5% improvement compared to LEDs without Ti3 C2 .
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Ruddlesden-Popper perovskites with a formula of (A')2(A) n -1B n X3 n +1 have recently gained widespread interest as candidates for the next generation of optoelectronic devices. The variations of organic cation, metal halide, and the number of layers in the structure lead to the change of crystal structures and properties for different optoelectronic applications. Herein, the different synthetic methods for 2D perovskite crystals and thin films are summarized and compared. The optoelectronic properties and the charge transfer process in the devices are also delved, in particular, for light-emitting diodes and solar cells.
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Although NiCoP has attracted much attention in the field of electrocatalysis, the study of its photocatalytic activity and mechanism have been somewhat limited. NiCoP/g-C3 N4 , synthesized by simple one-pot method, is a highly efficient photocatalyst for hydrogen production from water. NiCoP/g-C3 N4 exhibits a hydrogen evolution rate of 1643â µmol h-1 g-1 , which is 21â times higher than that of bare g-C3 N4 . The excellent performance is due to a combination of improved separation efficiency and effective charge transfer efficiency. The photogenerated charge behavior is characterized by the surface photovoltage (SPV), transient photovoltage (TPV), and photoluminescence spectroscopy. The photogenerated charge transport is investigated by electrochemical impedance spectroscopy and polarization curve. Moreover, the effective charge transfer efficiency was measured according to the mimetic apparent quantum yield. SPV and TPV measurements, whereby 10â vol % of a triethanolamine-water mixture was added into the testing system, were taken to simulate the real atmosphere for photocatalytic reaction, which can give rise to the photogenerated charge transfer process. A possible photocatalytic mechanism was also proposed. This study may provide an efficient theoretical basis to design transition metal phosphide cocatalyst-modified photocatalysts.
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Cobalto/química , Hidrogênio/química , Níquel/química , Nitrilas/química , Fósforo/química , Processos Fotoquímicos , Catálise , Espectroscopia Dielétrica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia Fotoeletrônica , Difração de Raios XRESUMO
Bisphosphonates (BPs) have been widely used in clinical treatment of bone diseases with increased bone resorption because of their strong affinity for bone and their inhibition of bone resorption. Recently, there has been growing interest in their improvement of bone formation. However, the effect of local controlled delivery of BPs is unclear. We used polylactide acid-glycolic acid copolymer (PLGA) as a drug carrier to deliver various doses of the bisphosphonate zoledronate (Zol) into the distal femur of 8-week-old Sprague-Dawley rats. After 6 weeks, samples were harvested and analyzed by micro-CT and histology. The average bone mineral density and mineralized bone volume fraction were higher with medium- and high-dose PLGA-Zol (30 and 300 µg Zol, respectively) than control and low-dose Zol (3 µg PLGA-Zol; p<0.05). Local controlled delivery of Zol decreased the numbers of osteoclast and increased the numbers of osteoblast. Moreover, local controlled delivery of medium- and high-dose Zol accelerated the expression of bone-formation markers. PLGA used as a drug carrier for controlled delivery of Zol may promote local bone formation.