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Mixed tin-lead perovskite solar cells (PSCs) have garnered much attention for their ideal bandgap and high environmental research value. However, poly (3,4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT: PSS), widely used as a hole transport layer (HTL) for Sn-Pb PSCs, results in unsatisfactory power conversion efficiency (PCE) and long-term stability of PSCs due to its acidity and moisture absorption. A synergistic strategy by incorporating histidine (HIS) into the PEDOT: PSS HTL is applied to simultaneously regulate the nucleation and crystallization of perovskite (PVK). HIS neutralizes the acidity of PEDOT: PSS and enhances conductivity. Especially, the coordination of the CâN and -COO- functional groups in the HIS molecule with Sn2+ and Pb2+ induces vertical growth of PVK film, resulting in the release of residual surface stress. Additionally, this strategy also optimizes the energy level alignment between the perovskite layer and the HTL, which improves charge extraction and transport. With these cooperative effects, the PCE of Sn-Pb PSCs reaches 21.46% (1 sun, AM1.5), maintaining excellent stability under a nitrogen atmosphere. Hence, the buried interface approach exhibits the potential for achieving high-performance and stable Sn-Pb PSCs.
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Isoniazid is an antibiotic primarily used in clinical treatment of tuberculosis, but excessive usage can lead to serious consequences such as hepatotoxicity, neurotoxicity, and even coma and death. Therefore, it is critical to exploit a quick, facile, and acute way for isoniazid analysis. In this work, we have demonstrated an efficient electrospinning-carbonation-wet chemistry reaction-calcination process to fabricate CuO/NiO nanotubes (NTs) as a promising nanozyme for peroxidase (POD) mimicking. In virtue of the distinct tubular structure and synergy between CuO and NiO from the mechanisms of both electron transfer and hydroxyl radical generation, a remarkably improved catalytic activity is realized for the CuO/NiO NTs compared with bare CuO and NiO samples. According to the admirable POD-like property, a rapid colorimetric detection for isoniazid is accomplished with a detection limit of 0.4 µM (S/N = 3) and favorable selectivity. In addition, the sensing capability of isoniazid in a real sample is also investigated with satisfactory results. This work offers a novel tactic to fabricate high-performance nanozymes with efficient isoniazid sensing capabilities to address challenges in disease treatment efficacy and public safety monitoring.
Assuntos
Isoniazida , Peroxidase , Antibacterianos , Biomimética , Cobre , Radical Hidroxila , Oxirredutases , Peroxidase/química , PeroxidasesRESUMO
CT and MR tools are commonly used to diagnose lumbar fractures (LF). However, numerous limitations have been found in practice. The aims of this study were to innovate and develop a spinal disease-specific neural network and to evaluate whether synthetic MRI of the LF affected clinical diagnosis and treatment strategies. A total of 675 LF patients who met the inclusion and exclusion criteria were included in the study. For each participant, two mid-sagittal CT and T2-weighted MR images were selected; 1350 pairs of LF images were also included. A new Self-pix based on Pix2pix and Self-Attention was constructed. A total of 1350 pairs of CT and MR images, which were randomly divided into a training group (1147 pairs) and a test group (203 pairs), were fed into Pix2pix and Self-pix. The quantitative evaluation included PSNR and SSIM (PSNR1 and SSIM1: real MR images and Pix2pix-generated MR images; PSNR2 and SSIM2: real MR images and Self-pix-generated MR images). The qualitative evaluation, including accurate diagnosis of acute fractures and accurate selection of treatment strategies based on Self-pix-generated MRI, was performed by three spine surgeons. In the LF group, PSNR1 and PSNR2 were 10.884 and 11.021 (p < 0.001), and SSIM1 and SSIM2 were 0.766 and 0.771 (p < 0.001), respectively. In the ROI group, PSNR1 and PSNR2 were 12.350 and 12.670 (p = 0.004), and SSIM1 and SSIM2 were 0.816 and 0.832 (p = 0.005), respectively. According to the qualitative evaluation, Self-pix-generated MRI showed no significant difference from real MRI in identifying acute fractures (p = 0.689), with a good sensitivity of 84.36% and specificity of 96.65%. No difference in treatment strategy was found between the Self-pix-generated MRI group and the real MRI group (p = 0.135). In this study, a disease-specific GAN named Self-pix was developed, which demonstrated better image generation performance compared to traditional GAN. The spine surgeon could accurately diagnose LF and select treatment strategies based on Self-pix-generated T2 MR images.
Assuntos
Vértebras Lombares , Imageamento por Ressonância Magnética , Fraturas da Coluna Vertebral , Humanos , Imageamento por Ressonância Magnética/métodos , Feminino , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/terapia , Adulto , Idoso , Tomografia Computadorizada por Raios X/métodos , Redes Neurais de ComputaçãoRESUMO
Tin-lead (Sn-Pb) mixed perovskite with a narrow bandgap is an ideal candidate for single-junction solar cells approaching the Shockley-Queisser limit. However, due to the easy oxidation of Sn2+, the efficiency and stability of Sn-Pb mixed perovskite solar cells (PSCs) still lag far behind that of Pb-based solar cells. Herein, highly efficient and stable FA0.5MA0.5Pb0.5Sn0.5I0.47Br0.03 compositional PSCs are achieved by introducing an appropriate amount of multifunctional Tin (II) oxalate (SnC2O4). SnC2O4 with compensative Sn2+ and reductive oxalate group C2O4 2- effectively passivates the cation and anion defects simultaneously, thereby leading to more n-type perovskite films. Benefitting from the energy level alignment and the suppression of bulk nonradiative recombination, the Sn-Pb mixed perovskite solar cell treated with SnC2O4 achieves a power conversion efficiency of 21.43%. More importantly, chemically reductive C2O4 2- effectively suppresses the notorious oxidation of Sn2+, leading to significant enhancement in stability. Particularly, it dramatically improves light stability.
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One-dimensional (1D) electrospun nanomaterials have attracted significant attention due to their unique structures and outstanding chemical and physical properties such as large specific surface area, distinct electronic and mass transport, and mechanical flexibility. Over the past years, the integration of metal sulfides with electrospun nanomaterials has emerged as an exciting research topic owing to the synergistic effects between the two components, leading to novel and interesting properties in energy, optics and catalysis research fields for example. In this review, we focus on the recent development of the preparation of electrospun nanomaterials integrated with functional metal sulfides with distinct nanostructures. These functional materials have been prepared via two efficient strategies, namely direct electrospinning and post-synthesis modification of electrospun nanomaterials. In this review, we systematically present the chemical and physical properties of the electrospun nanomaterials integrated with metal sulfides and their application in electronic and optoelectronic devices, sensing, catalysis, energy conversion and storage, thermal shielding, adsorption and separation, and biomedical technology. Additionally, challenges and further research opportunities in the preparation and application of these novel functional materials are also discussed.
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Developing high-performance, low-cost, and robust bifunctional electrocatalysts for overall water splitting is extremely indispensable and challenging. It is a promising strategy to couple highly active precious metals with transition metals as efficient electrocatalysts, which can not only effectively reduce the cost of the preparation procedure, but also greatly improve the performance of catalysts through a synergistic effect. Herein, Ru and Ni nanoparticles embedded within nitrogen-doped carbon nanofibers (RuNi-NCNFs) are synthesized via a simple electrospinning technology with a subsequent carbonization process. The as-formed RuNi-NCNFs represent excellent Pt-like electrocatalytic activity for the hydrogen evolution reaction (HER) in both alkaline and acidic conditions. Furthermore, the RuNi-NCNFs also exhibit an outstanding oxygen evolution reaction (OER) activity with an overpotential of 290 mV to achieve a current density of 10 mA cm-2 in alkaline electrolyte. Strikingly, owing to both the HER and OER performance, an electrolyzer with RuNi-NCNFs as both the anode and cathode catalysts requires only a cell voltage of 1.564 V to drive a current density of 10 mA cm-2 in an alkaline medium, which is lower than the benchmark of Pt/C||RuO2 electrodes. This study opens a novel avenue toward the exploration of high efficient but low-cost electrocatalysts for overall water splitting.
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BACKGROUND: Saline-sodic soils are widely distributed in arid and semi-arid regions around the world. High levels of salt and sodium inhibit the growth and development of crops. However, there has been limited reports on both osmotic potential in soil solutions (OPss) and characteristics of Na+ and K+ absorption in rice in saline-sodic soils under various amendments application. METHODS: A field experiment was conducted between 2009 and 2017 to analyze the influence of amendments addition to saline-sodic soils on rice growth and yield. Rice was grown in the soil with no amendment (CK), with desulfurization gypsum (DG), with sandy soil (SS), with farmyard manure (FM) and with the mixture of above amendments (M). The osmotic potential in soil solution, selective absorption of K+ over Na+ (SA), selective transport of K+ over Na+ (ST), the distribution of K+ and Na+and yield components in rice plants were investigated. RESULTS: The results indicated that amendments application have positive effects on rice yield. The M treatment was the best among the tested amendments with the highest rice grain yield. M treatment increased the OPss values significantly to relieve the inhibition of the water uptake by plants. Additionally, the M treatment significantly enhanced K+ concentration and impeded Na+ accumulation in shoots. SA values were reduced while ST values were increased for all amendments. In conclusion, a mixture of desulfurization gypsum, sandy soil and farmyard manure was the best treatment for the improvement of rice growth and yield in the Songnen Plain, northeast China.
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The mol-ecule of the title compound, C(15)H(13)ClN(2)O(2), adopts an E geometry about the C=N bond. The dihedral angle between the two benzene rings is 62.7â (2)°. In the crystal structure, mol-ecules are linked through inter-molecular N-Hâ¯O hydrogen bonds, forming chains running along the c axis.
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Synergistic effects play a crucial role in improving the catalytic activity of enzyme-like reactions. The preparation of hybrid nanomaterials for enzyme mimicking that display synergistic enhanced catalytic activity remains a formidable challenge. Titanium dioxide (TiO2)/molybdenum disulfide (MoS2) core-shell hybrid nanofibers were synthesized as efficient peroxidase mimics via a three-step approach involving electrospinning, calcination, and hydrothermal treatment. The resulting TiO2/MoS2 hybrid nanofibers exhibited synergistically enhanced peroxidase-like catalytic activity relative to the TiO2 nanofibers or MoS2 nanosheets alone. Based on the high peroxidase-like activity of the TiO2/MoS2 hybrid nanofibers, a simple colorimetric approach for the detection of l-glutathione (GSH) was developed, with a detection limit as low as 0.05⯵M. This study provides a simple and sensitive sensing platform for the detection of GSH, with prospective applications in colorimetric sensing, environmental monitoring, and medical diagnosis.