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The same class of steroid estrogen mixtures, coexisting in the environment of 17β-estradiol, estrone (E1), and ethinyl estradiol (EE2), have strong ability to disrupt the human endocrine system and are seriously prejudicial to the health of the organism and environmental safety. Herein, a highly sensitive and group-targeting environmental monitoring sensor was fabricated for a comprehensive analysis of multicomponent steroid estrogens (multi-SEs) in complex systems. This breakthrough was based on the highly sensitive photoelectrochemical response composite material CdSe NPs-TiO2 nanotube and highly group-specific aptamers. The optimized procedure exhibited not only high sensitivity in a wide range of concentrations from 0.1 to 50 nM, indeed, the minimum detection limit was 33 pM, but also strong resistance to interference. The affinity and consistent action pockets of this sensor enable selective detection of multi-SEs in complex systems. It subsequently was applied for the analysis of multi-SEs from three real samples in the environment including medical wastewater, river water, and tap water to provide a means to clarify the fate of multi-SEs in the process of migration and transformation. This monitoring sensor has a brilliant application prospect for the identification and monitoring of the same class of endocrine-disrupting chemical mixtures in environmental complex systems.A non-noble-metal hybrid catalyst (Ni2P/NPC-P), composed of N,P-doped porous carbon decorated with surface P-enriched Ni2P nanoparticles, is developed to address the urgent challenges associated with mass production of clean hydrogen fuel. The synthesis features one-pot pyrolysis of inexpensive fluid catalytic cracking slurry, graphitic carbon nitride, and inorganic salts, followed by a feasible surface phosphidation process. As a non-noble metal catalyst, Ni2P/NPC-P demonstrates excellent performance in hydrogen evolution reaction in alkaline electrolytes with a low overpotential of 73 mV at a current density of 10 mA cm-2 (η10) and a small Tafel slope of 56 mV dec-1, meanwhile exhibits durability with no significant η10 change after 2000 catalytic cycles. Theoretical calculation reveals that the negatively charged P-enriched surface accelerated the rate-determining transformation and desorption of OH*. In overall water splitting, the electrocatalyst achieves a low η10 of 1.633 V, promising its potential in the cost-effective mass production of hydrogen fuel.Electrocatalytic gas evolution reactions, where gaseous molecules are electrogenerated by reduction or oxidation of a species, play a central role in many energy conversion systems. Superaerophobic electrodes, usually constructed by their surface microstructures, have demonstrated excellent performance for electrochemical gas evolution reactions due to their bubble-repellent properties. Understanding and quantification of the gas bubble behavior including nucleation and dynamics on such microstructured electrodes is an important but underexplored issue. In this study, we reported a scanning electrochemical cell microscopy (SECCM) investigation of individual gas bubble nucleation and dynamics on nanoscale electrodes. A classic Pt film and a nonconventional transition-metal dichalcogenide MoS2 film with different surface topologies were employed as model substrates for both H2 and N2 bubble electrochemical studies. Interestingly, the nanostructured catalyst surface exhibit significantly less supersaturation for gas bubble nucleation and a notable increase of bubble detachment compared to its flat counterpart. Electrochemical mapping results reveal that there is no clear correlation between bubble nucleation and hydrogen evolution reaction (HER) activity, regardless of local electrode surface microstructures. Our results also indicate that while the hydrophobicity of the nanostructured MoS2 surface promotes bubble nucleation, it has little effect on bubble dynamics. This work introduces a new method for nanobubble electrochemistry on broadly interesting catalysts and suggests that the deliberate microstructure on a catalyst surface is a promising strategy for improving electrocatalytic gas evolution both in terms of bubble nucleation and elimination.Metal/semiconductor hetero-nanostructures are now considered as benchmark functional nanomaterials for many light-driven applications. Using laser-driven photodeposition to control growth of gold nanodots (NDs) onto CdSe/CdS dot-in-rods (DRs), we show that the addition of a dedicated hole scavenger (MeOH) is the cornerstone to significantly reduce to less than 3.5% the multiple-site nucleation and 2.5% the rate of gold-free DRs. This means, from a synthetic point of view, that rates up to 90% of single-tip DRs can be reproducibly achieved. Moreover, by systematically varying this hole scavenger concentration and the Au/DRs ratio on the one hand, and the irradiation intensity and the time exposure on the other hand, we explain how gold deposition switches from multisite to single-tipped and how the growth and final size of the single photodeposited ND can be controlled. A model also establishes that the results obtained based on these different varying conditions can be merged onto a single "master behavior" that summarizes and predicts the single-tip gold ND growth onto the CdSe/CdS DRs. We eventually use data from the literature on growth of platinum NDs onto CdS nanorods by laser-deposition to extend our investigation to another metal of major interest and strengthen our modeling of single metallic ND growth onto II-VI semiconducting nanoparticles. This demonstrated strategy can raise a common methodology in the synthesis of single-tip semiconductor-metal hybrid nanoheterodimers (NHDs), leading to advanced nanoparticles architectures for applications in areas as different as photocatalysis, hydrogen production, photovoltaics, and light detection.Solar steam generation (SSG) as a pollution-free and sustainable way for desalination or wastewater treatment has attracted great attention in recent years. Ertugliflozin mouse Herein, we report the fabrication of novel aerogels GAHAS and GAHAF composed of 3-aminopropyltriethoxysilane (KH550)-modified hollow glass microspheres (HGM) and reduced graphene oxide (RGO) by a sol-gel method for highly efficient SSG. The RGO can well wrap on modified HGM and form an interpenetrated porous structure with an excellent mechanical property. In addition, benefiting from the hollow structure of HGM, GAHAS obtained by supercritical CO2 drying well maintains the original structure of the hydrogel and shows low thermal conductivity (0.0823 W m-1 K-1) in the wet state and self-floating ability. Combined with its superhydrophilic wettability and high light absorption (ca. 93%), the as-prepared GAHAS shows an outstanding photothermal conversion efficiency of 89.13% under 1 sun (1 kW m-2) illumination and excellent stability. Moreover, from the simulated seawater outdoor solar desalination experiment, it was found that the concentrations of the four primary ions K+, Ca2+, Na+, and Mg2+ in purified water are 1.65, 0.09, 1.42, and 0.32 mg L-1, respectively, and fully meet drinking water standards. Thus, our GAHAS aerogel shows great potential for practical application in SSG. This work enriches the photothermal materials and may provide a new idea for design and creation of HGM-based photothermal materials with low thermal conductivity, tunable porosity, high mechanical strength, self-floating ability, and high solar energy conversion efficiency for SSG.Neurodegenerative diseases have been associated with brain metal accumulation, which produces oxidative stress (OS), matrix metalloproteinases (MMPs) induction, and neuronal cell death. Several metals have been reported to downregulate both the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway and the antioxidant enzymes regulated by it, mediating OS induction and neurodegeneration. Among a recently discovered family of multitarget 7-amino-phenanthridin-6-one derivatives (APH) the most promising compounds were tested against metal-induced cell death and OS in SN56 cells. These compounds, designed to have chelating activity, are known to inhibit some MMPs and to present antioxidant and neuroprotective effects against hydrogen peroxide treatment to SN56 neuronal cells. However, the mechanisms that mediate this protective effect are not fully understood. The obtained results show that compounds APH1, APH2, APH3, APH4, and APH5 were only able to chelate iron and copper ions among all metals studied and that APH3, APH4, and APH5 were also able to chelate mercury ion. However, none of them was able to chelate zinc, cadmium, and aluminum, thus exhibiting selective chelating activity that can be partly responsible for their neuroprotective action. Otherwise, our results indicate that their antioxidant effect is mediated through induction of the Nrf2 pathway that leads to overexpression of antioxidant enzymes. Finally, these compounds exhibited neuroprotective effects, reversing partially or completely the cytotoxic effects induced by the metals studied depending on the compound used. APH4 was the most effective and safe compound.The origin of the low densities of electrically active defects in Pb halide perovskite (HaP), a crucial factor for their use in photovoltaics, light emission, and radiation detection, remains a matter of discussion, in part because of the difficulty in determining these densities. Here, we present a powerful approach to assess the defect densities, based on electric field mapping in working HaP-based solar cells. The minority carrier diffusion lengths were deduced from the electric field profile, measured by electron beam-induced current (EBIC). The EBIC method was used earlier to get the first direct evidence for the n-i-p junction structure, at the heart of efficient HaP-based PV cells, and later by us and others for further HaP studies. This manuscript includes EBIC results on illuminated cell cross sections (in operando) at several light intensities to compare optoelectronic characteristics of different cells made by different groups in several laboratories. We then apply a simple, effective single-level defect model that allows deriving the densities (Nr) of the defect acting as recombination center. We find Nr ≈ 1 × 1013 cm-3 for mixed A cation lead bromide-based HaP films and ∼1 × 1014 cm-3 for MAPbBr3(Cl). As EBIC photocurrents are similar at the grain bulk and boundaries, we suggest that the defects are at the interfaces with selective contacts rather than in the HaP film. These results are relevant for photovoltaic devices as the EBIC responses distinguish clearly between high- and low-efficiency devices. The most efficient devices have n-i-p structures with a close-to-intrinsic HaP film, and the selective contacts then dictate the electric field strength throughout the HaP absorber.Mercury concentrations in the Laurentian Great Lakes waters are among the lowest reported in the literature, while game fish concentrations approach consumption advisory limits, particularly in Lakes Superior, Huron, and Michigan, indicating efficient methylmercury transfer from water to game fish. To determine if increased transfer efficiency is evident within the lower food web, we measured (2010-2018) mercury and dissolved organic carbon (DOC) in water, and in size-sieved seston, dietary tracers (carbon and nitrogen isotope ratios), phytoplankton methylmercury bioaccumulation, and methylmercury biomagnification between increasing seston size fractions. We observed consistently low filter-passing methylmercury ( less then 0.010 ng L-1) and comparatively variable DOC (1.1 to 3.4 mg L-1) concentrations. Methylmercury biomagnification factors between size-sieved seston were similar between lakes. Bioaccumulation factors in phytoplankton were among the highest in the literature (log 5.5 to 6.1), exceeding those in oceans, smaller lakes, and streams, and was influenced by DOC.
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