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•Quantitative analysis is used to evaluate the removal of microplastics in global WWTPs.•The filter-based technologies perform better microplastics removal efficiency.•Mechanisms of ...critical treatment technologies in microplastics removal are summarized.•An average of 7.2 billion day−1 microplastics entered the river from WWTPs.•Specific microplastics shall be highlighted besides the common microplastics.
Wastewater treatment plants (WWTPs) are considered to be the main sources of microplastic contaminants in the aquatic environment, and an in-depth understanding of the behavior of microplastics among the critical treatment technologies in WWTPs is urgently needed. In this paper, the characteristics and removal of microplastics in 38 WWTPs in 11 countries worldwide were reviewed. The abundance of microplastics in the influent, effluent, and sludge was compared. Then, based on existing data, the removal efficiency of microplastics in critical treatment technologies were compared by quantitative analysis. Particularly, detailed mechanisms of critical treatment technologies including primary settling treatment with flocculation, bioreactor system, advanced oxidation and membrane filtration were discussed. Thereafter, the abundance load and ecological hazard of the microplastics discharged from WWTPs into the aquatic and soil environments were summarized. The abundance of microplastics in the influent ranged from 0.28 particles L−1 to 3.14 × 104 particles L−1, while that in the effluent ranged from 0.01 particles L−1 to 2.97 × 102 particles L−1. The microplastic abundance in the sludge within the range of 4.40 × 103–2.40 × 105 particles kg−1. In addition, there are still 5.00 × 105–1.39 × 1010 microplastic particles discharged into the aquatic environment each day Moreover, among the critical treatment technologies, the quantitative analysis revealed that filter-based treatment technologies exhibited the best microplastics removal efficiency. Fibers and microplastics with large particle sizes (0.5–5 mm) were easily separated by primary settling. Polyethene and small-particle size microplastics (<0.5 mm) were easily trapped by bacteria in the activated sludge of bioreactor system. The negative impact of microplastics from wastewater treatment plant was worthy of attention. Moreover, unknown transformation products of microplastics and their corresponding toxicity need in-depth research.
The current boom of safe and renewable energy storage systems is driving the recent renaissance of Zn‐ion batteries. However, the notorious tip‐induced dendrite growth on the Zn anode restricts their ...further application. Herein, the first demonstration of constructing a flexible 3D carbon nanotube (CNT) framework as a Zn plating/stripping scaffold is constituted to achieve a dendrite‐free robust Zn anode. Compared with the pristine deposited Zn electrode, the as‐fabricated Zn/CNT anode affords lower Zn nucleation overpotential and more homogeneously distributed electric field, thus being more favorable for highly reversible Zn plating/stripping with satisfactory Coulombic efficiency rather than the formation of Zn dendrites or other byproducts. As a consequence, a highly flexible symmetric cell based on the Zn/CNT anode presents appreciably low voltage hysteresis (27 mV) and superior cycling stability (200 h) with dendrite‐free morphology at 2 mA cm−2, accompanied by a high depth of discharge (DOD) of 28%. Such distinct performance overmatches most of recently reported Zn‐based anodes. Additionally, this efficient rechargeability of the Zn/CNT anode also enables a substantially stable Zn//MnO2 battery with 88.7% capacity retention after 1000 cycles and remarkable mechanical flexibility.
A flexible 3D carbon nanotube (CNT) network is proposed as a highly conductive skeleton for Zn deposition to achieve a dendrite‐free Zn/CNT anode. Taking the advantages of low Zn nucleation overpotential and homogeneously distributed electric field, the Zn/CNT anode exhibits a prolonged cycling life over 200 h at high depth of discharge of 28%, which also enables a stable Zn//MnO2 battery.
Advanced flexible batteries with high energy density and long cycle life are an important research target. Herein, the first paradigm of a high‐performance and stable flexible rechargeable ...quasi‐solid‐state Zn–MnO2 battery is constructed by engineering MnO2 electrodes and gel electrolyte. Benefiting from a poly(3,4‐ethylenedioxythiophene) (PEDOT) buffer layer and a Mn2+‐based neutral electrolyte, the fabricated Zn–MnO2@PEDOT battery presents a remarkable capacity of 366.6 mA h g−1 and good cycling performance (83.7% after 300 cycles) in aqueous electrolyte. More importantly, when using PVA/ZnCl2/MnSO4 gel as electrolyte, the as‐fabricated quasi‐solid‐state Zn–MnO2@PEDOT battery remains highly rechargeable, maintaining more than 77.7% of its initial capacity and nearly 100% Coulombic efficiency after 300 cycles. Moreover, this flexible quasi‐solid‐state Zn–MnO2 battery achieves an admirable energy density of 504.9 W h kg−1 (33.95 mW h cm−3), together with a peak power density of 8.6 kW kg−1, substantially higher than most recently reported flexible energy‐storage devices. With the merits of impressive energy density and durability, this highly flexible rechargeable Zn–MnO2 battery opens new opportunities for powering portable and wearable electronics.
A highly flexible rechargeable quasi‐solid‐state Zn–MnO2@PEDOT battery is demonstrated for the first time. The battery affords a prominent energy density of 504.9 W h kg−1 (33.95 mW h cm−3), substantially outstripping most of the recently reported batteries and supercapacitors. Additionally, benefiting from a protective layer and modified electrolyte, such a Zn–MnO2@PEDOT battery delivers a good durability of 77.7% after 300 cycles.
Although metasurfaces have shown great potential for manipulating light, most previously realized meta-devices suffer from
angular dispersions, making them unfavorable for many applications. Here, we ...propose a general strategy to realize optical metasurfaces with desired angular dispersions based on carefully controlling both the near-field couplings between meta-atoms and the radiation pattern of a single meta-atom. Utilizing such a strategy, we experimentally demonstrate a series of optical meta-devices with predesigned angular dispersions, including two incident-angle-
absorbers, one incident-angle-
absorber, and one multifunctional meta-polarizer whose functionality changes from a perfect mirror to a half-waveplate as the excitation angle varies. Finally, we design a
meta-device using meta-atom arrays with purposely controlled angular dispersions and numerically demonstrate that it can exhibit distinct wavefront-control functionalities when illuminated at different incident angles. Our findings establish a new platform for achieving angle-multiplexed functional meta-devices, significantly expanding the wave-manipulation capabilities of optical metasurfaces.
Currently, the main bottleneck for the widespread application of Ni–Zn batteries is their poor cycling stability as a result of the irreversibility of the Ni‐based cathode and dendrite formation of ...the Zn anode during the charging–discharging processes. Herein, a highly rechargeable, flexible, fiber‐shaped Ni–Zn battery with impressive electrochemical performance is rationally demonstrated by employing Ni–NiO heterostructured nanosheets as the cathode. Benefiting from the improved conductivity and enhanced electroactivity of the Ni–NiO heterojunction nanosheet cathode, the as‐fabricated fiber‐shaped Ni–NiO//Zn battery displays high capacity and admirable rate capability. More importantly, this Ni–NiO//Zn battery shows unprecedented cyclic durability both in aqueous (96.6% capacity retention after 10 000 cycles) and polymer (almost no capacity attenuation after 10 000 cycles at 22.2 A g−1) electrolytes. Moreover, a peak energy density of 6.6 µWh cm−2, together with a remarkable power density of 20.2 mW cm−2, is achieved by the flexible quasi‐solid‐state fiber‐shaped Ni–NiO//Zn battery, outperforming most reported fiber‐shaped energy‐storage devices. Such a novel concept of a fiber‐shaped Ni–Zn battery with impressive stability will greatly enrich the flexible energy‐storage technologies for future portable/wearable electronic applications.
An ultrastable, flexible fiber‐shaped Ni–Zn battery with impressive electrochemical performance is rationally demonstrated by employing Ni–NiO heterostructured nanosheets as the cathode. This Ni–NiO//Zn battery exhibits unprecedented cyclic durability both in aqueous (96.6% capacity retention after 10 000 cycles) and polymer (almost no capacity attenuation after 10 000 cycles at 22.2 A g−1) electrolytes.
Strong damping‐like spin‐orbit torque (τDL) has great potential for enabling ultrafast energy‐efficient magnetic memories, oscillators, and logic. So far, the reported τDL exerted on a thin‐film ...magnet must result from an externally generated spin current or from an internal non‐equilibrium spin polarization in non‐centrosymmetric GaMnAs single crystals. Here, for the first time a very strong, unexpected τDL is demonstrated from current flow within ferromagnetic single layers of chemically disordered, face‐centered‐cubic CoPt. It is established here that the novel τDL is a bulk effect, with the strength per unit current density increasing monotonically with the CoPt thickness, and is insensitive to the presence or absence of spin sinks at the CoPt surfaces. This τDL most likely arises from a net transverse spin polarization associated with a strong spin Hall effect, while there is no detectable long‐range asymmetry in the material. These results broaden the scope of spin‐orbitronics and provide a novel avenue for developing single‐layer‐based spin‐torque memory, oscillator, and logic technologies.
A strong, unexpected bulk damping‐like spin‐orbit torque is observed within chemically disordered ferromagnetic single layers that have no detectable long‐range asymmetry. This bulk torque, which most likely arises from a net transverse spin polarization associated with the spin Hall effect, increases monotonically with the ferromagnet thickness and is insensitive to the neighbor layers. These results broaden the scope of spin‐orbitronics.
Ischemic stroke (IS) is a detrimental neurological disease with limited treatments options. It has been challenging to define the roles of brain cell subsets in IS onset and progression due to ...cellular heterogeneity in the CNS. Here, we employed single-cell RNA sequencing (scRNA-seq) to comprehensively map the cell populations in the mouse model of MCAO (middle cerebral artery occlusion). We identified 17 principal brain clusters with cell-type specific gene expression patterns as well as specific cell subpopulations and their functions in various pathways. The CNS inflammation triggered upregulation of key cell type-specific genes unpublished before. Notably, microglia displayed a cell differentiation diversity after stroke among its five distinct subtypes. Importantly, we found the potential trajectory branches of the monocytes/macrophage’s subsets. Finally, we also identified distinct subclusters among brain vasculature cells, ependymal cells and other glia cells. Overall, scRNA-seq revealed the precise transcriptional changes during neuroinflammation at the single-cell level, opening up a new field for exploration of the disease mechanisms and drug discovery in stroke based on the cell-subtype specific molecules.
Abstract
Many applications requiring both spectral and spatial information at high resolution benefit from spectral imaging. Although different technical methods have been developed and commercially ...available, computational spectral cameras represent a compact, lightweight, and inexpensive solution. However, the tradeoff between spatial and spectral resolutions, dominated by the limited data volume and environmental noise, limits the potential of these cameras. In this study, we developed a deeply learned broadband encoding stochastic hyperspectral camera. In particular, using advanced artificial intelligence in filter design and spectrum reconstruction, we achieved 7000–11,000 times faster signal processing and ~10 times improvement regarding noise tolerance. These improvements enabled us to precisely and dynamically reconstruct the spectra of the entire field of view, previously unreachable with compact computational spectral cameras.
Parrotfish (Scaridae) feed by biting stony corals. To investigate how their teeth endure the associated contact stresses, we examine the chemical composition, nano- and microscale structure, and the ...mechanical properties of the steephead parrotfish Chlorurus microrhinos tooth. Its enameloid is a fluorapatite (Ca5(PO4)3F) biomineral with outstanding mechanical characteristics: the mean elastic modulus is 124 GPa, and the mean hardness near the biting surface is 7.3 GPa, making this one of the stiffest and hardest biominerals measured; the mean indentation yield strength is above 6 GPa, and the mean fracture toughness is ∼2.5 MPa·m1/2, relatively high for a highly mineralized material. This combination of properties results in high abrasion resistance. Fluorapatite X-ray absorption spectroscopy exhibits linear dichroism at the Ca L-edge, an effect that makes peak intensities vary with crystal orientation, under linearly polarized X-ray illumination. This observation enables polarization-dependent imaging contrast mapping of apatite, a method to quantitatively measure and display nanocrystal orientations in large, pristine arrays of nano- and microcrystalline structures. Parrotfish enameloid consists of 100 nm-wide, microns long crystals co-oriented and assembled into bundles interwoven as the warp and the weave in fabric and therefore termed fibers here. These fibers gradually decrease in average diameter from 5 μm at the back to 2 μm at the tip of the tooth. Intriguingly, this size decrease is spatially correlated with an increase in hardness.
Metal oxides (MOs) with multiple active sites are regarded as one of the most potential active materials for high‐performance supercapacitor (SC) constructions. Engineering oxygen vacancies into MOs ...can effectively modulate their electronic properties, subtly induce impurity states in their bandgaps, and considerably optimize their electrical conductivity. Benefiting from these advantageous properties, the resultant oxygen‐defective electrodes generally embed more electrochemical active sites and present better charge storage capability in contrast to the pristine sample. Particular research attention has been given to the realization of precise oxygen vacancy introduction into MOs and the fine tuning of their properties. This review presents an overview of recent accomplishments in developing new oxygen‐defective MOs for advanced SC assembly. Different strategies for oxygen vacancy productions are summarized and compared. The specific roles of oxygen vacancies in the electrochemical performance enhancement are fully addressed and the relevant impact factors are discussed in detail. Finally, the key challenges and future opportunities in this rapidly developing field are highlighted.
Engineering oxygen vacancies into metal oxides (MOs) can modulate their electronic properties and optimize their electrochemical performance. Herein, an overview of recent accomplishments in developing oxygen‐defective MOs for supercapacitors is presented. Different synthetic strategies, specific roles, and the relevant impact factors of oxygen vacancies are summarized and discussed in detail. The key challenges and future opportunities are highlighted.
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