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Multilingual perspectives have become the mainstream research paradigm in language motivation studies lately. The motivational interplay between English and French, as two important foreign languages in China, has received little academic attention, but this topic is becoming increasingly significant for language education in the era of global English. This study set out to explore the motivational differences between English majors and non-English majors learning French as the second foreign language (SFL) in a Chinese university, and identify the influencing factors of learners’ motivation. A motivation scale was designed in the form of questionnaire, and participants (n = 56) from two classes were tested. Variation sampling was then adopted for interviews to capture learners’ multiple motivational profiles. The results reveal that the learners’ SFL motivation fluctuates constantly with their first foreign language being English. Overall, the non-English majors have a significantly higher motivation than English majors. This proves that the conclusion in the literature of L2 English having a negative impact on L3 motivation is oversimplified. We found it applies to English majors, but not to non-English majors. We also proposed an original three-dimensional motivation model, taking into account the influencing factors at the macro, meso and micro levels. It helps to reveal the dynamic interplay of different motivational forces. Teachers are suggested to help maintain and promote learners’ motivation by constantly strengthening supporter language awareness and emphasizing the benefits of being multilinguals.

Volume expansion of the Si-C anode during the charging/discharging process causes continuous fracture/formation of the solid electrolyte interface (SEI), which leads to rapid capacity fading. Here, we designed a MgF2-modified separator (MF-PP) to construct a fluorine-rich SEI layer by generating more LiF. The robust SEI layer formed can alleviate the volume stress and prevent crack growth in Si-C electrodes. After 450 cycles, the Si-C||MF-PP half cell retained a reversible capacity of 543.2 mAh g–1, while the LFP||MF-PP||Si-C full cell maintained a reversible capacity of 103.4 mAh g–1with high Coulombic efficiency after 100 cycles. This facile and low-cost separator modification strategy provides an easily scalable approach to develop stable Si-based anodes for next-generation high-energy-density systems.

• A novel gradient pseudo-precipitates heterostructure (GPHS) is designed and fabricated for non-heat treatable 5xxx aluminum alloy. • The proposed GPHS achieves enhanced strength-ductility synergy for Al-2.5%Mg alloy. • The formation mechanism of the GPHS is revealed as an inter-diffusion mechanism activated and promoted by various sub-structures. • HDI strengthening and strain hardening of GPHS are demonstrated as dominant effects in deformation mechanism. Heterostructures of alloyed composites, comprising heterogeneous domains with dramatically different constitutive properties, hold remarkable potential to expand the realm of material design systems and resolve the trade-off between strength and ductility. This study introduces an innovative materials design method for synthesizing gradient pseudo-precipitates heterostructure (GPHS) in non-heat-treatable Al-2.5%Mg alloys. Utilizing cost-effective mild steel as both the diffusion source and protective layer, this heterostructure is achieved through pin-less friction stir-assisted cyclic localized deformation process. Exogenous Fe atoms diffuse across the interface by friction stir-induced heat conduction, forming Fe-Al second-phase particles in the Al alloy matrix. A rapid inter-diffusion mechanism is activated in conjunction with dense dislocation walls, grain boundaries, and sub-structures, resulting in the formation of pseudo-precipitates. These pseudo-precipitates are ultimately dispersed in a gradient distribution throughout the entire thickness of the Al alloy matrix induced by localized incremental deformation. The GPHSed Al-2.5%Mg alloy exhibits an enhanced synergy of strength and ductility, with a uniform elongation increase from 11 % to 21.2 %, while maintaining the strength. Multiple strengthening and hardening mechanisms, such as solid solution strengthening, dislocation hardening, and second phase strengthening, work synergistically to promote mechanical performance. Notably, the hetero-deformation between hard pseudo-precipitates and soft Al alloy matrix induces additional strain hardening, leading to high ductility. This work provides a fresh perspective on the design and fabrication of high-performance alloys with advanced heterostructures, especially for non-heat-treatable alloys. [Display omitted] [ABSTRACT FROM AUTHOR]

The potentials of steel/Al alloy laminated structures for lightweighting in the automotive industry are increasingly recognized, particularly for reducing energy consumption. However, optimal formability and high-temperature stability in these hybrid structures remain a persistent challenge during the current manufacturing process. This challenge arises from the intricate control required over the Fe-Al intermetallic compounds (IMCs) layer at the dissimilar interface. In this work, steel/Al alloy bilayer laminated structures were fabricated by a thermomechanical joining-forming approach involving pin-less friction stir-assisted incremental sheet forming with synchronous bonding technology. These structures exhibit desirable shear bonding strength of 129 MPa (equivalent to 93.5 % of the shear strength of the AA5052-H32 base material). Mechanisms of local plastic flow, viscoplastic flow, and fast inter-atomic diffusion are evaluated using quasi-static elements. A phenomenological bond fraction model is proposed to describe the collapse of interfacial ellipsoidal microvoids. Cohesive numerical simulation reveals that the interfacial plastic strain is dispersedly distributed with slight cohesive damage due to stable heat-force conditions. Experimental results with confirmed models demonstrate the stability of the programmable process for mechanical-metallurgical bonding and coordinated deformation. Furthermore, a cyclic thermomechanical loading mode is proven effective in tuning interfacial diffusion and inhibiting the growth of the IMC layer. This integrated joining-forming strategy is also applicable to other challenging metallic pairs that are prone to brittle IMCs.

Superplastic forming is a practical method to manufacture complex-shaped parts of titanium alloys with large deformation. Laminated parts of dissimilar titanium alloys fabricated by superplastic forming can achieve excellent performance by combining the advantages of components. This work displays the superplastic tension behavior and microstructural evolution of dissimilar TC4/SP700 laminate prepared by the diffusion bonding process. Two titanium alloys can achieve metallurgical bonding at parameters of 800 ℃/1 h/5 MPa. Except for dynamic recrystallization and grain growth behaviors upon superplastic tension, stress-induced phase transformation plays an important role in α to β phase transformation apart from the elevated temperature. The superplastic deformation can be attributed to the grain boundary sliding accommodated multiplex motion of dislocations. In addition, the retained strengths of all dissimilar TC4/SP700 laminates after superplastic deformation with different strain rates and temperatures range from 807 to 890 MPa.

Despite the great potential of CRISPR-based detection, it has not been competitive with other market diagnostics for on-site and in-home testing. Here we dissect the rate-limiting factors that undermine the performance of Cas12b- and Cas13a-mediated detection. In one-pot testing, Cas12b interferes with loop-mediated isothermal amplification by binding to and cleaving the amplicon, while Cas13a directly degrades the viral RNA, reducing its amplification. We found that the protospacer-adjacent motif-interacting domain engineered Cas12b accelerated one-pot testing with 10–10,000-fold improved sensitivity, and detected 85 out of 85 SARS-CoV-2 clinical samples with a sensitivity of 0.5 cp μl−1, making it superior to wild-type Cas12b. In parallel, by diminishing the interference of Cas13a with viral RNA, the optimized Cas13a-based assay detected 86 out of 87 SARS-CoV-2 clinical samples at room temperature in 30 min with a sensitivity of 0.5 cp μl−1. The relaxed reaction conditions and improved performance of CRISPR-based assays make them competitive for widespread use in pathogen detection.

Prussian blue analogs (PBAs) are a potential choice for cathodes in sodium-ion batteries. However, their electrochemical performance is hindered by intrinsic structural vacancies and weak electronic conductivity, resulting in a reduced reversible capacity, multiplicative ability, and cycle stability. Herein, the carbon-blended Na2CoFe(CN)6(COHCF@C) prepared by a controlled crystallization method displays improved electrochemical characteristics. With 70% residual capacity after 200 cycles, the reversible specific capacity of the COHCF@C is 123 mAh g–1at 1 C. Furthermore, the COHCF@C also exhibits higher structural stability in aqueous electrolytes. Based on experimental results, this enhancement can be attributed to the introduction of carbon, slowing down the crystallization process and resulting in higher crystallinity. Additionally, the reduced water content leads to fewer defects, which improves the utilization of active sites. Overall, the finding provides an experimental basis and theoretical guidance for the application of PBA cells.

An ingenious thermo-mechanical treatment process was utilized on a Fe-5.95Mn-1.55Si-1.0Al-0.055C medium-Mn steel to investigate the effect of fibrous δ-ferrites on mechanical properties. With a large enough cold-rolling reduction ratio (∼70%), the morphology of coarsened fibrous δ-ferrites is tailored into homogeneous distributed fragments, which provides a precondition to launch the present study. Direct experimental evidence has been obtained that fibrous δ-ferrites are a double-edged sword for mechanical properties: it improves ductility (by 3.5% ± 1.1%) but decreases tensile strength (by 65 ± 11.5 MPa). This can be related to the accommodation effect of dislocations within coarsened fibrous δ-ferrite grains as soft phase, which decreases the degree of dislocation pile-ups in martensitic matrix, resulting in the limited strengthening effect of dislocations. Additionally, despite significant directionality along rolling direction, the fibrous δ-ferrite grains do not result in anisotropic properties.

In this experiment, we systematically investigated the microstructure evolution, mechanical properties, and deformation behaviors as functions of annealing temperature using cold-rolled Fe-0.05C–6Mn–1Al-1.5Si steel. Almost all annealed specimens are composed of the equiaxed and granular α-ferrite (α) grains due to recrystallization, reversed austenite (γ) grains because of reversed transformation from deformed martensite, and fibrous δ-ferrite (δ) grains only undergoing recovery during intercritical annealing except for 760 °C. It is interesting that several annealing twins are formed within γ grains. The outstanding combination of strength and ductility is obtained for annealing at 740 °C. The tensile strength and total elongation are 980 MPa and 32.1%, which are attributed to the ultrafine grains and optimal TRIP effect associated with rational γ content and stability. A phenomenon that yield point elongation (YPE) gradually shortens with increased γ content and decreased γ stability is observed. What's more, the mechanism that active α′ formation can promote the improvement of work hardening rate and further curtail YPE is verified using deep-cryogenic treatment. Based on SEM observation, microscopic strain of δ grains appears nearly consistent with matrix (α and γ grains) during tensile process, although δ phase presents as fibrous morphology with coarse size.

Induction of angiogenesis has enormous potential in the treatment of ischemic diseases and the promotion of bulk tissue regeneration. However, the poor activity of angiogenic cells and proangiogenic factors after transplantation is the main problem that imposes its wide applications. Recent studies have found that the development of nanomaterials has solved this problem to some extent. Nanomaterials can be mainly classified into inorganic nanomaterials represented by metals, metal oxides and metal hydroxides, and organic nanomaterials including DNA tetrahedrons, graphene, graphene oxide, and carbon nanotubes. These nanomaterials can induce the release of angiogenic factors either directly or indirectly, thereby initiating a series of signaling pathways to induce angiogenesis. Moreover, appropriate surface modifications of nanomaterial facilitate a variety of functions, such as enhancing its biocompatibility and biostability. In clinical applications, nanomaterials can promote the proliferation and differentiation of endothelial cells or mesenchymal stem cells, thereby promoting the migration of hemangioblast cells to form new blood vessels. This review outlines the role of nanomaterials in angiogenesis and is intended to provide new insights into the clinical treatment of systemic and ischemic diseases.

Cation substitution in spinel cobaltites (e.g., ACo2O4, in which A = Mn, Fe, Co, Ni, Cu, or Zn) is a promising strategy to precisely modulate their electronic structure/properties and thus improve the corresponding electrochemical performance for water splitting. However, the fundamental principles and mechanisms are not fully understood. This research aims to systematically investigate the effects of cation substitution in spinel cobaltites derived from mixed-metal-organic frameworks on the oxygen evolution reaction (OER). Among the obtained ACo2O4catalysts, FeCo2O4showed excellent OER performance with a current density of 10 mA·cm−2at an overpotential of 164 mV in alkaline media. Both theoretical calculations and experimental results demonstrate that the Fe substitution in the crystal lattice of ACo2O4can significantly accelerate charge transfer, thereby achieving enhanced electrochemical properties. The crystal field of spinel ACo2O4, which determines the valence states of cations A, is identified as the key factor to dictate the OER performance of these spinel cobaltites.

For a representative medium Mn steel with the actual chemical composition of Fe-5.95 Mn-1.55Si-1.03Al-0.055 C (wt. %), the effect of cold-rolling deformation on microstructural evolution and mechanical properties was investigated systematically. The thickness of coarse δ-ferrite grains decreases with the increase of cold-rolling reduction, and when the cold-rolling reduction ratio reaches up to a certain value, these δ-ferrite grains can be broken into small pieces due to the severe plastic deformation. Additionally, a critical cold-rolling reduction ratio for recrystallization exists. Below this critical reduction value, the medium Mn steel after austenite reverted transformation (ART) annealing remains lath-shaped structure originating from the initial martensitic morphology, and when recrystallization occurs, however, submicron equiaxed grains dominate. The initial microstructure before ART annealing, which is usually determined by cold-rolling reduction, strongly influences not only the martensitic/ferritic matrix, but also reverted austenite grains. Non-recrystallization matrix promotes the formation of acicular reverted austenite, whereas recrystallization forces the austenite grains spherical and promotes the grain size of austenite homogenizing. Under the situation of non-recrystallization, the cold-rolling reduction prior to ART annealing only has a negligible effect on the final mechanical properties. However, the occurrence of recrystallization results in not only the yielding plateau, i.e., discontinuous yielding, but also the remarkable increase of yield strength.

The unhealthy electrodeposition leads to uncontrolled growth and random fracture of Li, causing safety problems. Here we elaborate on the growth mechanism of Li on different substrates by integrating overpotential testing and Gibbs free energy calculating. Induced nucleation sites are brought into the substrate to trap Li preferentially, reducing the primary deposition barrier and contributing to the uniform nucleation of Li. The Li grows along the sites where the pits grow on the carbon substrate. The secure connection between the metal and the substrate can be used to stabilize the bulk metal. In addition, the external magnetic field during electrodeposition homogenizes the direction of ion movement and promotes uniform deposition. At the same time, the 3D frame distributes the ion flux homogenization, providing enough space to mitigate the volume change. The design of the substrate provides a unique inside-out growth path for metal, which guides the uniform deposition of Li and effectively inhibits the growth of dendrites. The electrochemical performance using CC/Co3O4/Li electrode is significantly improved in the full battery with sulfur as the cathode. This work explores the growth mechanism of Li metal and guides stable dendrite-free Li electrode fabrication.

The intrinsic volumetric stress during cycling is the main obstacle for developing Si-based materials as high-energy-density lithium-ion battery anodes. Elastic binders have been demonstrated as an efficient approach to alleviate the stress of Si. Herein, we design a tough 3D hard/soft polymeric network (LPTS) using lithiated poly(acrylic acid), silk sericin, and highly branched tannic acid. Covalent cross-linking provides a robust mechanical strength to endure the large stress. The formed multiple hydrogen bonds with bonding energies between 3.46 and 25 kcal mol–1can effectively dissipate the stress through sequential hydrogen bond disassociation. The multifunctional LPTS binder maintains the integrity of the Si-based electrodes during repeated discharging/charging. Additionally, Li+can be transferred via a Li-conducting group (−COOLi), thereby enhancing the ionic conductivity of electrodes. Consequently, the Si/LPTS electrode exhibits an improved initial Coulombic efficiency and excellent durability over 400 cycles. Meanwhile, this binder is also suitable for Si–C anodes, enabling stable cycling at a high areal capacity >3.6 mAh cm–2and delivering 72.2% capacity retention for the LFP||Si–C/LPTS full cell after 200 cycles. This study provides insight into developing efficient Si-based binders that are facile and low-cost for next-generation high-energy-density systems.

Anaerobic digestion (AD) is an important biological resource recovery process, where microorganisms play key roles for material transformation. There has been some knowledge about the prokaryotic community and antibiotic resistance genes (ARGs) in AD, but there has been very limited knowledge of phages. In this study, samples from a full-scale AD plant were collected over 13 months, sequenced, and analyzed for viral and prokaryotic metagenomes. Totally, 3015 viral operational taxonomic units (vOTUs) were detected, mostly assigned to Caudoviricetes. The phage community had faster temporal variation than the prokaryotic community. Warm seasons harbored a higher abundance of both temperate phages and broad host-range phages. Seven ARGs of 6 subtypes were carried by 20 vOTUs, a representative ermTgene was synthesized and expressed, and the resistance activity in the host was examined, confirming the real activity of virus-carried ARGs in the AD process. Some of the ARGs were horizontally transferred between the phage and prokaryotic genomes. However, phage infection was not found to contribute to ARG transfer. This study provided an insight into the ecological patterns of the phage community, confirmed the antibiotic resistance activity of virus-carried ARGs, evaluated the contribution of phages on the ARG prevalence, and laid the foundation for the control strategies of the community and antibiotic resistance in the AD process.

Confining Transition metal oxides (TMOs) nanoparticles in porous carbon is an effective strategy to improve its electrochemical performance. Herein, the large grain size Co-based metal-organic framework (Co-MOF) was used as precursor to synthesize core-shell structure of Co3O4encapsulated in nitrogen-doped carbon (denoted as L-Co3O4@NC). The in-situ synthesized L-Co3O4@NC exhibits a unique interconnected and hierarchical porous structure. Owing to the unique structu Line14ral merits including fast charge transmission and Li+diffusion, effectively accommodate the volume change, and promote the access of Li+, the L-Co3O4@NC exhibits excellent lithium storage performance in terms of high specific capacity (1389 mAh g−1at 0.1A g−1after 50 cycles), enhanced rate capability (1373, 1182 and 945 mAh g−1at 0.5, 1 and 2 A g−1, respectively), and cycling stability at large current density (1183 mAh g−1at 1 A g−1and 960 mAh g−1at 2 A g−1after 200 cycles), which outperforms most of recently reported Co3O4based electrodes. This work provides a new avenue for developing Co-based anode materials with high performance in energy storage field.

Previous studies revealed that LiNO3can enhance the cyclic stability of lithium‑sulfur (LiS) batteries by creating a solid electrolyte interface protecting the lithium electrode. However, this study investigated the effect of LiNO3and concentration in the electrolyte, first studied under low and high sulfur loading. It is confirmed that adding a small amount of LiNO3inhibits the shuttle effect phenomenon in LiS batteries, and the Coulombic efficiency was significantly improved. Appropriately increasing the concentration of LiNO3to 2 % could prolong the cycle life. However, when LiNO3is excessive, the rate and cycling performance decrease. The design of practical LiS batteries requires more research on the parameters of electrolyte additives under high‑sulfur-loading conditions. After gradient increasing the sulfur loading, the low concentration of LiNO3cannot play the best performance of the battery, so it is necessary to improve the concentration of LiNO3further. It is evident that adding LiNO3in LiS batteries has certain benefits, and the optimal amount of additive is related to the value of sulfur loading.

SiOx-based material is a promising candidate for lithium-ion batteries (LIBs) owing to its high theoretical capacity. The inherent disadvantages of poor electronic conductivity and large volume variation can be solved by constructing the outermost carbon layer and reserving internal voids. However, the practical application of SiOx/C composites remains a great challenge due to the unsatisfactory energy density. Herein, we propose a facile synthetic approach for fabricating SNG/H-SiOx@C composites, which are constructed by amorphous carbon, hollow SiOx(H-SiOx), and spherical natural graphite (SNG). H-SiOxalleviates volume expansion, while amorphous carbon promotes Li+migration and stable solid electrolyte interphase (SEI) formation. The as-prepared SNG/H-SiOx@C demonstrates a high reversible capacity (465 mAh g–1), excellent durability (93% capacity retention at 0.5C after 500 cycles), lower average delithiation potential than SNG (0.143 V after 500 cycles), and a 14% gravimetric energy density improvement at a loading level of 4.5 mg cm–2. Even at a compacted density of 1.5 g cm–3, the SNG/H-SiOx@C anode presents a modest volume deformation of 14.3% after 100 cycles at 0.1C.

•Properties and catalytic mechanism of molten alkali carbonate (MAC) are presented.•Adding MAC for coal and biomass gasification over CO2enhanced CO production.•MAC catalyst reduced reaction temperature, activation energy, and tar.•Coal reactivity enhances by AAEMs exist in biomass ash during co-gasification.•Existent of Si/Al inhabit co-gasification due to alkali aluminosilicates formation.