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Topic evolution analysis is one of the research hotspots of public opinion monitoring. The evolution analysis of microblog hot topics is of great practical significance to network users and network regulators. To solve the problem of OBTM topic mixing and high probability of redundant words, the OBTM based on topic labels and prior parameters (LPOBTM) is proposed in this paper. According to the topic labels, the microblog text set is divided into two types of data sets with and without topic labels. Different document-topic prior parameters are set. Based on document-topic probability distribution in the previous time slice, the intensity ranking of all topics is carried out by drawing lessons from the Sigmod function. Thus, the prior parameter calculation method of topic-word distribution on current time slice is optimized. The experimental results show that LPOBTM can describe the content evolution of topics more accurately, and has lower model perplexity. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) has been utilized as a versatile feedstock or promising energy carrier in a variety of fields, yet the implementation of high‐rate H2 production presents a grand challenge for its readily accessible application. Herein, a newly alkali‐Al/acid hybrid fuel cell (3AHFC) that shows the capability of rapidly producing H2 upon delivering a considerably high energy density is reported, which is set up by paring Al anode in alkaline anolyte with acidic catholyte and a relatively cheap nanohybrid of Ru nanoparticle decorating crumpled reduced graphene oxide (Ru/c‐rGO) as cathode catalysts. It is demonstrated that the 3AHFC can release a power density of up to 240.6 mW cm−2 with a Faradic efficiency of approaching 99% for fast H2 generation (300 mA cm−2). Such hybrid electrolyte H2‐generation fuel cell can also be extended for either seawater anolyte or metallic Mg anode, presenting great promise for the practice feasibility of on‐site H2 production for applications in tough or even extreme environments. [ABSTRACT FROM AUTHOR]

We offer a new methodology for the construction of annual population stocks over the very long run. Our method does not require the assumption of a closed economy, and can be used in situations in which local annual gross flows are obtainable. Combining gross flows with intermittent census-type data, it is possible to arrive at local, regional and national population stock estimates at annual frequencies. We provide an application to early modern and nineteenth century Portugal, using a large sample of parish-level statistics up to the first modern census of 1864. All six major regions of the country are considered. [ABSTRACT FROM AUTHOR]

Additive manufacturing of (quasi−) solid‐state (QSS) electrochemical energy storage devices (EES) highlights the significance of gel polymer electrolytes (GPEs) design. Creating well‐bonded electrode‐GPEs interfaces in the electrode percolative network via printing leads to large‐scale production of customized EES with boosted electrochemical performance but has proven to be quite challenging. Herein, we report on a versatile, universal and scalable approach to engineer a controllable, seamless electrode‐GPEs interface via free radical polymerization (FRP) triggered by MXene at room temperature. Importantly, MXene reduces the dissociation enthalpy of persulfate initiators and significantly shortens the induction period accelerated by SO4−, enabling the completion of FRP within minutes. The as‐formed well‐bonded electrode‐GPEs interface homogenizes the electrical and concentration fields (i.e., Zn2+), therefore suppressing the dendrites formation, which translates to long‐term cycling (50,000 times), high energy density (105.5 Wh kg−1) and power density (9231 W kg−1) coupled with excellent stability upon deformation in the zinc‐ion hybrid capacitors (ZHCs). Moreover, the critical switch of the rheological behaviours of the polymer electrolyte (as aqueous inks in still state and become solids once triggered by MXene) perfectly ensures the direct all‐printing of electrodes and GPEs with well‐bonded interface in between, opening vast possibilities for all‐printed QSS EES beyond ZHCs. [ABSTRACT FROM AUTHOR]

It is highly attractive to develop efficient water electrolysis route to implement hydrogen generation in a low‐cost way, which while requires excess energy to surmount the activation barriers majorly limited by oxygen evolution reaction at anode side. Herein, we report an acid‐alkali asymmetric‐electrolyte electrolyzer (AAAE) that can achieve substantial energy saving for electrolysis hydrogen generation, thanks to the assistance of electrochemical neutralization energy (ENE) and urea oxidation reaction (UOR). To this end, free‐standing Ni(OH)2 nanosheets on carbon cloth (Ni(OH)2−NSs/CC) is fabricated as catalytic anode for alkaline UOR, which manifests impressively high catalytic activity with delivering 10 mA cm−2 at 1.32 V and long‐term durability. The as‐developed AAAE only requires an applied voltage of 0.66 V to release the electrolysis current of 10 mA cm−2, yielding the H2 Faraday efficiency close to 100 % along with H2 production rate of 183.8 μmol h−1. [ABSTRACT FROM AUTHOR]

The basification method was used for the optimized preparation of a new flocculant, poly‐ferric aluminum phosphate sulfate (PPFAS). The Ferron method was used to analyze the distributions of the Fe and Al forms in PPFAS. The conditions of the optimized preparation of PPFAS were as follows: the n(OH)/n(Fe) ratio of 0.6, the n(P)/n(Fe) ratio of 1/5, and the reaction temperature of 60°C. After each addition of NaOH and Na3PO4, the reaction was allowed to proceed for 10 min, and then, the reaction continued on the shaking table for 1 h; the aging process continued for 60 h at 25°C. Under these conditions, the content of the effective component, [Fe + Al]b, could reach up to 60%. The order of the removal rates of the mixed heavy metals by PPFAS is Cu(II)> Cr(III)> Pb(II)> Zn(II)> Cd(II). The order of the removal rates of the mixed complex heavy metals is EDTA‐Cd(II)> EDTA‐Zn(II)> EDTA‐Pb(II)> EDTA‐Cu(II)> EDTA‐Cr(III). © 2017 American Institute of Chemical Engineers Environ Prog, 37: 240–248, 2018 [ABSTRACT FROM AUTHOR]

Aqueous zinc-sulfur batteries are a high-capacity and cost-effective energy storage technology. However, the performance is plagued by the dissolution of intermediate polysulfides formed during conversion. Here, this issue is addressed by developing aqueous rechargeable Zn-sulfurized polyacrylonitrile (SPAN) batteries using tandem catalytic systems, containing water and tetraglyme (G4) with iodine (I 2 ) additives. Mechanistic study and experiments reveal that the fully conjugated molecular configurations circumvent the formation of soluble polysulfides and enable reversible co-storage of H + /Zn 2+ with multiple redox-active centers. The reduced I 2 by G4 activates I - /I 3 - redox couple in SPAN, reducing activation energy, and accelerating Zn-ion transfer kinetics. Additionally, it stabilizes the Zn anode by forming an organic-inorganic interphase that induces the generation of the predominant (002) plane. The as-assembled Zn-SPAN batteries exhibit excellent performances, with a high capacity of 1260.4 mAh g -1 at 0.2 A g -1 , a high-rate performance (409.3 mAh g -1 at 5 A g -1 ), and a long cycling stability (81.8% capacity remained over 800 cycles at 2 A g -1 ). This work takes a crucial step forward in organosulfur compounds accompanied by multi-electron transfer for the high-performance aqueous zinc-ion batteries., (© 2024 Wiley‐VCH GmbH.)

On-body batteries with hydrogel electrolytes are a pivotal enabling technology to drive bioelectronics for healthcare and sports, yet they are prone to failure due to dynamic interfacial interference, accompanied by e-waste production. Here, dynamic imine chemistry is proposed to design on-electrode paintable biogel electrolytes that feature temperature-controlled reversible phase transition (gelling within 1.5 min) and ultrafast self-healing capability (6 s), establishing a dynamically self-adaptive interface on cyclically deforming electrodes for shielding on-body Zn-ion batteries from interfacial interference. Consequently, the deformed Zn anode shows an exceptional cycling stability of 400 h regardless of the bending radius, and the as-assembled Zn-I 2 battery delivers sufficient durability to endure 5000 deformation cycles, together extending to 1300 h and 15 000 deformation cycles via dynamically restarting the interfacial electric field, respectively. Also, the features of recyclability, biodegradation, and biocompatibility make the proposed on-body Zn-I 2 batteries appealing in terms of sustainability and biosafety, enabling their successful power supply of heart rate monitors in sports. This work demonstrates the promise of dynamic biogel chemistry for green and biorelated energy-storage systems.

Direct regeneration of spent lithium-ion batteries presents a promising approach to effectively reuse valuable resources and benefit the environment. Unlike controlled laboratory conditions that commonly facilitate impurity purification and minimize structural damage, the LiFePO 4 cathode black mass faces significant interfacial challenges, including structure deterioration, cathode-electrolyte interphase residues, and damage from storage procedures, which hinder lithium replenishment and structure regeneration. Here, a metal-solvent chelation reaction using a lithium acetylacetonate solution is introduced to address these challenges under ambient conditions. This method regulates the near-surface structure through strong chelation between Acac ‒ anions and Fe (III) elements, thus effectively eliminating the degraded amorphous phase and residual fluorine compounds. By direct lithium connection and reducing diffusion barriers, the reconstructed surface facilitates the re-lithiation process. The regenerated LiFePO 4 cathodes demonstrate a capacity retention of 88.5% after 400 cycles at 1 C, while also outperforming traditional recycling methods in terms of environmental and economic benefits. This approach provides a promising solution for regenerating degraded LiFePO 4 cathodes from actual dismantled black mass, thereby accelerating the practical application of battery recycling., (© 2024 Wiley‐VCH GmbH.)

Hybrid materials with a rational organic-inorganic configuration can offer multifunctionality and superior properties. This principle is crucial but challenging to be applied in designing the solid electrolyte interphase (SEI) on lithium metal anodes (LMAs), as it substantially affects Li + transport from the electrolyte to the anode. Here, an artificial SEI with an ultrahigh fluorine content (as high as 70.12 wt %) can be successfully constructed on the LMA using a high-voltage electrosynthesis strategy. This SEI consists of ultrafine lithium fluoride nanocrystals embedded in a fluorinated organic matrix, exhibiting excellent passivation and mechanical strength. Notably, the organic-inorganic interface demonstrates a high dielectric constant that enables fast Li + transport throughout the SEI. Consequently, LMA coated with this SEI substantially enhances the cyclability of both half-cells and full cells, even under rigorous conditions. This work demonstrates the potential of rationally designed hybrid materials via a unique electrosynthetic approach for advanced electrochemical systems.

Aqueous zinc batteries possess intrinsic safety and cost-effectiveness, but dendrite growth and side reactions of zinc anodes hinder their practical application. Here, we propose the extended substrate screening strategy for stabilizing zinc anodes and verify its availability (d substrate : d Zn(002)  = 1: 1→d substrate : d Zn(002) =n:1, n = 1, 2). From a series of calculated phyllosilicates satisfying d substrate  ≈ 2d Zn(002) , we select vermiculite, which has the lowest lattice mismatch (0.38%) reported so far, as the model to confirm the effectiveness of "2d Zn(002) " substrates for zinc anodes protection. Then, we develop a monolayer porous vermiculite through a large-scale and green preparation as a functional coating for zinc electrodes. Unique "planting Zn(002) seeds" mechanism for "2d Zn(002) " substrates is revealed to induce the oriented growth of zinc deposits. Additionally, the coating effectively inhibits side reactions and promotes zinc ion transport. Consequently, the modified symmetric cells operate stably for over 300 h at a high current density of 50 mA cm -2 . This work extends the substrate screening strategy and advances the understanding of zinc nucleation mechanism, paving the way for realizing high-rate and stable zinc-metal batteries., (© 2024. The Author(s).)

The Li-metal anode has been recognized as the most promising anode for its high theoretical capacity and low reduction potential. However, the major drawbacks of Li metal, such as high reactivity and large volume expansion, can lead to dendrite growth and solid electrolyte interface (SEI) fracture. An in situ artificial inorganic SEI layer, consisting of lithium nitride and lithium sulfide, is herein reported to address the dendrite growth issues. Porous graphene oxide films are doped with sulfur and nitrogen (denoted as SNGO) to work as an effective lithium host. The SNGO film enables the in situ formation of an inorganic-rich SEI layer, which facilitates the transport of Li-ions, improves SEI mechanical strength, and avoids SEI fracture. In addition, COMSOL simulation results reveal that the microchannels fabricated by the 3D printing technique further shorten the Li-ion transfer pathways and homogenize heat and stress distribution in the batteries. As a result, the assembled anode shows low capacity fading of 0.1% per cycle at 2 C rate with the sulfur cathode. In addition, the high lithium utilization of the SNGO host enables the anode to provide a stable capacity at low negative/positive electrode ratios under 3 in LiS batteries., (© 2022 Wiley-VCH GmbH.)