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Ammonia, as an alternative fuel for internal combustion engines, can achieve nearly zero carbon emissions. Although the development of the pure ammonia engine is limited by its poor combustion characteristics, ammonia–hydrocarbon mixed combustion can effectively improve the combustion of ammonia fuel. With the increase in the ammonia fuel proportion in the fuel mixture, a large number of nitrogen oxides (NOX) and unburned ammonia may be discharged, which have a poor impact on the environment. In this study, the performance of selective catalytic reduction (SCR) aftertreatment technology in reducing NOX and ammonia emissions from ammonia–diesel dual-fuel engines was investigated using simulation. A good cross-dimensional model was established under the coupling effect, though the effect of a single-dimensional model could not be presented. The results show that when the exhaust gas in the engine cylinder is directly introduced into the SCR without additional reducing agents such as urea, unburned ammonia flowing into SCR model is in excess, and there will be only ammonia at the outlet; however, if the unburned ammonia fed into the SCR model is insufficient to reduce NO, the ammonia concentration at the outlet will be 0. NOX can be 100% effectively reduced to N2 under most engine conditions; thus, unburned ammonia in exhaust plays a role in reducing NOX emissions from ammonia–diesel dual-fuel engines. However, when the concentration of unburned ammonia in the exhaust gas of an ammonia–diesel dual-fuel engine is large, its ammonia emissions are still high even after the SCR. In addition, the concentrations of N2O after SCR do not decrease, but increase by 50.64 in some conditions, the main reason for which is that by the action of the SCR catalyst, NO2 is partially converted into N2O, resulting in an increase in its concentration at the SCR outlet. Adding excessive air or oxygen into the SCR aftertreatment model can not only significantly reduce the ammonia concentration at the outlet of the model without affecting the NOX conversion efficiency of SCR, but inhibit N2O production to some extent at the outlet, thus reducing the unburned ammonia and NOX emissions in the tail gas of ammonia–diesel dual-fuel engines at the same time without the urea injection. Therefore, this study can provide theoretical guidance for the design of ammonia and its mixed-fuel engine aftertreatment device, and provide technical support for reducing NOX emissions of ammonia and its mixed fuel engines.

Hybrid halide perovskites are among the most promising candidates for next‐generation photovoltaics. The most investigated perovskite solar cells are lead based, which poses environmental concerns, making finding sustainable alternatives a pressing issue. Tin‐based halide perovskites are attracting interest as an alternative. However, their application in photovoltaics is hindered by the high concentration of defects and sensitivity to oxidation, compromising their performance and stability. Herein, perfluoroarene organic cations, namely 2‐(perfluorophenyl)methylammonium (F‐BNA) and 1,4‐(perfluorophenyl)dimethylammonium (F‐PDMA), are applied to form layered (2D) Ruddlesden–Popper and Dion–Jacobson tin‐based perovskites, respectively. Following a detailed structural and optoelectronic characterization, the perfluoroarenes are applied to formamidinium (FA)‐based FASnI3 perovskite solar cells and an effective solvent is identified for their processing, 2‐pentanol. While F‐PDMA forms a 2D/3D heterostructure, F‐BNA remains assembled as a molecular interlayer, demonstrating higher photovoltaic performance with limited operational stability. This challenges the conventional role of mixed‐dimensional heterostructures in tin perovskite photovoltaics and opens new perspectives for advanced material design and device engineering. Herein, perfluoroarene cations, 2‐(perfluorophenyl)methylammonium (F‐BNA) and 1,4‐(perfluorophenyl)dimethylammonium (F‐PDMA), are applied to form layered Ruddlesden–Popper and Dion–Jacobson tin‐based perovskites. Following a detailed structural and optoelectronic characterization, a suitable solvent is identified and the perfluoroarenes are applied to formamidinium (FA)‐based FASnI3 perovskite solar cells, demonstrating higher photovoltaic performance with limited operational stability, revealing new perspectives for tin perovskite photovoltaics.

The stability of hybrid organic–inorganic halide perovskite semiconductors remains a significant obstacle to their application in photovoltaics. To this end, the use of low‐dimensional (LD) perovskites, which incorporate hydrophobic organic moieties, provides an effective strategy to improve their stability, yet often at the expense of their performance. To address this limitation, supramolecular engineering of noncovalent interactions between organic and inorganic components has shown potential by relying on hydrogen bonding and conventional van der Waals interactions. Here, the capacity to access novel LD perovskite structures that uniquely assemble through unorthodox S‐mediated interactions is explored by incorporating benzothiadiazole‐based moieties. The formation of S‐mediated LD structures is demonstrated, including one‐dimensional (1D) and layered two‐dimensional (2D) perovskite phases assembled via chalcogen bonding and S–π interactions. This involved a combination of techniques, such as single crystal and thin film X‐ray diffraction, as well as solid‐state NMR spectroscopy, complemented by molecular dynamics simulations, density functional theory calculations, and optoelectronic characterization, revealing superior conductivities of S‐mediated LD perovskites. The resulting materials are applied in n‐i‐p and p‐i‐n perovskite solar cells, demonstrating enhancements in performance and operational stability that reveal a versatile supramolecular strategy in photovoltaics. A new generation of low‐dimensional hybrid halide perovskite materials assembled via chalcogen bonding and S–π interactions is demonstrated by a combination of techniques, including X‐ray diffraction and solid‐state nuclear magnetic resonance spectroscopy, complemented by molecular dynamics simulations, density functional theory calculations, and optoelectronic characterization, revealing superior conductivities and enhancements in performance and operational stabilities in perovskite solar cells.

The effects of X elements (Ag, Ni, Si, Zr, Mg, Al and Zn) doping with amount of 0.926 at% on the structural, mechanical and thermodynamic properties, as well as the electrical properties of Cu were calculated systematically using a first-principles density functional theory (DFT). The calculated formation enthalpy and binding energy indicate that all the Cu107X alloys can be formed and are thermodynamic stable. The B/G values of Cu dilute solutions are between 2.1 and 3.1, both are greater than 1.75, the Poisson's ratios ν are between 0.295 and 0.355, which means that all of Cu107X are plastic materials. Cu107Si and Cu107Zn had the larger Vickers hardness, the value of which were 6.18GPa, 5.97GPa, respectively. By means of molecular dynamics and the Kubo-Green-Wood formula, the electrical conductivities of Cu108 and Cu107X were calculated, the results show that all elements doping will reduce the conductivity of Cu, and the conductivity of Cu107Ag in Cu107X alloys is the largest, and its value is 3.56*107S/m.

The first-principles calculations were performed to research effects of elements X (Au, Be, Pd, Y, Ca, Cu, In and Zn) on mechanical and electronic properties of Ag with the density function theory (DFT). A supercell consisting of 107 atoms of Ag and one solute atom X was used. It was found that the bulk modulus of Ag dilute solutions were affected by the bulk modulus of pure alloying elements as well as their volume. The shear modulus G trend to decrease with increase of volume of Ag caused by alloying addition, but Ag-X covalent bond had positive correlation with shear modulus G. All of Ag107X alloys were ductility since theirs B/G ratio, Poisson's ratios ν were larger than 1.75 and 0.33, respectively. Comparing to other calculated Ag107X alloys, Ag107Be and Ag107Cu had the larger Vickers hardness, the value of which were 3.96GPa, 3.86GPa, respectively. There were not only metallic bonds (Ag-Ag) but also covalent bonds (Ag-X) in Ag107X alloys. The strong covalent bonds between Y, Zn, Ca and Ag were mainly caused by orbital hybridization between Y-5p orbital, Zn-3d orbital, Ca-3d orbitals and Ag-4d, 5s and 5p orbitals.

Highlights Alkaline earth cations are successfully incorporated into perovskite lattice with the aid of sulfonic acid anions, while alkaline earth metal halides are lack of doping capacity. The sulfonic acid anions effectively regulate the crystallization of perovskite and passivate the metallic Pb 0 defect states, thereby improving the power conversion efficiency of perovskite solar cells. By comparing the property of FACF 3 SO 3 and Ca(CF 3 SO 3 ) 2 -doped perovskite films, the impact of suppressing halide migration with an activation energy of 1.246 eV is attributed to Ca 2+ cations, thus providing methodology for decoupling the effects of cations and anions. The past decade has witnessed the rapid increasement in power conversion efficiency of perovskite solar cells (PSCs). However, serious ion migration hampers their operational stability. Although dopants composed of varied cations and anions are introduced into perovskite to suppress ion migration, the impact of cations or anions is not individually explored, which hinders the evaluation of different cations and further application of doping strategy. Here we report that a special group of sulfonic anions (like CF 3 SO 3 − ) successfully introduce alkaline earth ions (like Ca 2+ ) into perovskite lattice compared to its halide counterparts. Furthermore, with effective crystallization regulation and defect passivation of sulfonic anions, perovskite with Ca(CF 3 SO 3 ) 2 shows reduced PbI 2 residue and metallic Pb 0 defects; thereby, corresponding PSCs show an enhanced PCE of 24.95%. Finally by comparing the properties of perovskite with Ca(CF 3 SO 3 ) 2 and FACF 3 SO 3 , we found that doped Ca 2+ significantly suppressed halide migration with an activation energy of 1.246 eV which accounts for the improved operational stability of Ca(CF 3 SO 3 ) 2 -doped PSCs, while no obvious impact of Ca 2+ on trap density is observed. Combining the benefits of cations and anions, this study presents an effective method to decouple the effects of cations and anions and fabricate efficient and stable PSCs.

NMDA receptors (NMDARs) are crucial for excitatory synaptic transmission and synaptic plasticity. The number and subunit composition of synaptic NMDARs are tightly controlled by neuronal activity and sensory experience, but the molecular mechanism mediating NMDAR trafficking remains poorly understood. Here, we report that RIM1, with a well-established role in presynaptic vesicle release, also localizes postsynaptically in the mouse hippocampus. Postsynaptic RIM1 in hippocampal CA1 region is required for basal NMDAR-, but not AMPA receptor (AMPAR)-, mediated synaptic responses, and contributes to synaptic plasticity and hippocampus-dependent memory. Moreover, RIM1 levels in hippocampal neurons influence both the constitutive and regulated NMDAR trafficking, without affecting constitutive AMPAR trafficking. We further demonstrate that RIM1 binds to Rab11 via its N terminus, and knockdown of RIM1 impairs membrane insertion of Rab11-positive recycling endosomes containing NMDARs. Together, these results identify a RIM1-dependent mechanism critical for modulating synaptic function by facilitating membrane delivery of recycling NMDARs. Rab3-interacting molecules (RIMs) are a key component of the presynaptic active zone that regulate neurotransmitter release. Here, the authors show that RIM1 also has postsynaptic function to organize NMDA receptors and synaptic response.

Bimetallic lined pipe (BLP) has been increasingly used in offshore and subsea oil and gas structures, but how to identify the invisible inner defects such as liner wall thinning and interface debonding is a challenge for future development. A nondestructive testing (NDT) method based on pulsed eddy current testing (PECT) has been proposed to face these difficulties. The inspection of the BLP specimen (AISI1020 base tube and SS304 liner) is implemented from outside of the pipe by using a transmitter–receiver-type PECT probe consisting of two induction coils. By simplifying the BLP specimen to stratified conductive plates, the electromagnetic field interaction between the PECT probe and specimen is analytically modeled, and the probe inspection signals due to liner wall thinning and interface debonding are calculated. In order to highlight the weak response (in microvolts) from the liner, the inspection signals are subtracted by the signal, which is calculated in the case of only having a base tube, yielding differential PECT signals. The peak voltage of the differential signal is selected to characterize the liner wall thinning and interface debonding due to its distinguishable and linear variation. Experiment verification is also carried out on a double-walled specimen simulated by a combination of a Q235 casing pipe and SS304 tubes of different sizes. The experimental results basically agree with the analytical predictions. The peak value of the PECT signal has an ascending and descending variation with the increase in the remaining liner wall thickness and debonding gap, respectively, while the negative peak value shows opposite changes. The peak value exhibits a larger sensitivity than the negative peak value. The proposed method shows potential promise in practical applications for the evaluation of the inner defects in BLP lines.

As silicon‐based electronics approach the physical limits of Moore's Law, 2‐Dimensional (2D) semiconductors emerge as promising candidates for next‐generation electronic devices due to their atomic‐scale thickness and inherently high carrier mobilities. These materials offer superior electrostatic control, mitigating short‐channel effects while enabling continued device scaling. However, challenges such as contact resistance and suboptimal channel properties continue to impede carrier transport, necessitating advanced mobility engineering strategies. This review comprehensively evaluates recent approaches to enhance carrier mobility in 2D semiconductor‐based field‐effect transistors (FETs), including doping, metal‐semiconductor interface optimization, effective mass engineering, scattering mechanism manipulation, work function tuning, and strain engineering. These strategies improve critical device parameters like current drive, subthreshold swing, and on/off ratios by optimizing carrier transport efficiency. By linking material‐level advancements to circuit‐level performance, this work underscores the pivotal role of mobility engineering in enabling scalable, high‐performance 2D electronics. These insights pave the way for transitioning 2D materials from laboratory research to practical applications, overcoming the limitations of conventional silicon technologies and driving innovations in high‐performance, energy‐efficient electronics. This review highlights device‐level strategies to optimize carrier transport in 2D‐FETs, focusing on channel engineering and contact interface design. Techniques such as doping, strain tuning, and contact resistance reduction are discussed to improve mobility and drive current. By bridging material innovation and device performance, it outlines pathways toward scalable, high‐performance 2D semiconductor electronics.

Surface modification of three-dimensional (3D)-printed titanium (Ti) scaffolds with hydroxyapatite (HA) has been a research hotspot in biomedical engineering. However, unlike HA coatings on a plain surface, 3D-printed Ti scaffolds have inherent porous structures that influence the characteristics of HA coatings and osteointegration. In the present study, HA coatings were successfully fabricated on 3D-printed Ti scaffolds using plasma spray and electrochemical deposition, named plasma sprayed HA (PSHA) and electrochemically deposited HA (EDHA), respectively. Compared to EDHA scaffolds, HA coatings on PSHA scaffolds were smooth and continuous. In vitro cell studies confirmed that PSHA scaffolds have better potential to promote bone mesenchymal stem cell adhesion, proliferation, and osteogenic differentiation than EDHA scaffolds in the early and late stages. Moreover, in vivo studies showed that PSHA scaffolds were endowed with superior bone repair capacity. Although the EDHA technology is simpler and more controllable, its limitation due to the crystalline and HA structures needs to be improved in the future. Thus, we believe that plasma spray is a better choice for fabricating HA coatings on implanted scaffolds, which may become a promising method for treating bone defects.