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Membrane trafficking pathways mediate key microglial activities such as cell migration, cytokine secretion, and phagocytosis. However, the underlying molecular mechanism remains poorly understood. Previously, we found that synaptotagmin‐11 (Syt11), a non‐Ca2+‐binding Syt associated with Parkinson's disease (PD) and schizophrenia, inhibits cytokine release and phagocytosis in primary microglia. Here we reported the in vivo function of Syt11 in microglial immune responses using an inducible microglia‐specific Syt11‐conditional‐knockout (cKO) mouse strain. Syt11‐cKO resulted in activation of microglia and elevated mRNA levels of IL‐6, TNF‐α, IL‐1β, and iNOS in various brain regions under both resting state and LPS‐induced acute inflammation state in adult mice. In a PD mouse model generated by microinjection of preformed α‐synuclein fibrils into the striatum, a reduced number of microglia migrated toward the injection sites and an enhanced phagocytosis of α‐synuclein fibrils by microglia were found in Syt11‐cKO mice. To understand the molecular mechanism of Syt11 function, we identified its direct binding proteins vps10p‐tail‐interactor‐1a (vti1a) and vti1b. The linker domain of Syt11 interacted with both proteins and a peptide derived from it competitively inhibited the interaction of Syt11 with vti1a/vti1b in vitro and in cells. Importantly, application of this peptide induced more cytokine secretion in wild‐type microglia upon LPS treatment, phenocopying defects in Syt11 knockdown cells. Altogether, we propose that Syt11 inhibits microglial activation in vivo and regulates cytokine secretion through interactions with vti1a and vti1b. [ABSTRACT FROM AUTHOR]

Aqueous Zn−Mn battery has been considered as the most promising scalable energy‐storage system due to its intrinsic safety and especially ultralow cost. However, the traditional Zn−Mn battery mainly using manganese oxides as cathode shows low voltage and suffers from dissolution/disproportionation of the cathode during cycling. Herein, for the first time, a high‐voltage and long‐cycle Zn−Mn battery based on a highly reversible organic coordination manganese complex cathode (Manganese polyacrylate, PAL−Mn) was constructed. Benefiting from the insoluble carboxylate ligand of PAL−Mn that can suppress shuttle effect and disproportionationation reaction of Mn3+ in a mild electrolyte, Mn3+/Mn2+ reaction in coordination state is realized, which not only offers a high discharge voltage of 1.67 V but also exhibits excellent cyclability (100 % capacity retention, after 4000 cycles). High voltage reaction endows the Zn−Mn battery high specific energy (600 Wh kg−1 at 0.2 A g−1), indicating a bright application prospect. The strategy of introducing carboxylate ligands in Zn−Mn battery to harness high‐voltage reaction of Mn3+/Mn2+ well broadens the research of high‐voltage Zn−Mn batteries under mild electrolyte conditions. [ABSTRACT FROM AUTHOR]

Aqueous Zn−Mn battery has been considered as the most promising scalable energy‐storage system due to its intrinsic safety and especially ultralow cost. However, the traditional Zn−Mn battery mainly using manganese oxides as cathode shows low voltage and suffers from dissolution/disproportionation of the cathode during cycling. Herein, for the first time, a high‐voltage and long‐cycle Zn−Mn battery based on a highly reversible organic coordination manganese complex cathode (Manganese polyacrylate, PAL−Mn) was constructed. Benefiting from the insoluble carboxylate ligand of PAL−Mn that can suppress shuttle effect and disproportionationation reaction of Mn3+ in a mild electrolyte, Mn3+/Mn2+ reaction in coordination state is realized, which not only offers a high discharge voltage of 1.67 V but also exhibits excellent cyclability (100 % capacity retention, after 4000 cycles). High voltage reaction endows the Zn−Mn battery high specific energy (600 Wh kg−1 at 0.2 A g−1), indicating a bright application prospect. The strategy of introducing carboxylate ligands in Zn−Mn battery to harness high‐voltage reaction of Mn3+/Mn2+ well broadens the research of high‐voltage Zn−Mn batteries under mild electrolyte conditions. [ABSTRACT FROM AUTHOR]

Cellulose is the most abundant biopolymer on Earth, which is synthesized by plants, bacteria, and animals, with source-dependent properties. Cellulose containing β-1,4-linked D-glucoses further assembles into hierarchical structures in microfibrils, which can be processed to nanocellulose with length or width in the nanoscale after a variety of pretreatments including enzymatic hydrolysis, TEMPO-oxidation, and carboxymethylation. Nanocellulose can be mainly categorized into cellulose nanocrystal (CNC) produced by acid hydrolysis, cellulose nanofibrils (CNF) prepared by refining, homogenization, microfluidization, sonification, ball milling, and the aqueous counter collision (ACC) method, and bacterial cellulose (BC) biosynthesized by the Acetobacter species. Due to nontoxicity, good biodegradability and biocompatibility, high aspect ratio, low thermal expansion coefficient, excellent mechanical strength, and unique optical properties, nanocellulose is utilized to develop various cellulose nanocomposites through solution casting, Layer-by-Layer (LBL) assembly, extrusion, coating, gel-forming, spray drying, electrostatic spinning, adsorption, nanoemulsion, and other techniques, and has been widely used as food packaging material with excellent barrier and mechanical properties, antibacterial activity, and stimuli-responsive performance to improve the food quality and shelf life. Under the driving force of the increasing green food packaging market, nanocellulose production has gradually developed from lab-scale to pilot- or even industrial-scale, mainly in Europe, Africa, and Asia, though developing cost-effective preparation techniques and precisely tuning the physicochemical properties are key to the commercialization. We expect this review to summarise the recent literature in the nanocellulose-based food packaging field and provide the readers with the state-of-the-art of this research area. [ABSTRACT FROM AUTHOR]

Phytoplankton patterns have been observed widely in aquatic systems. Although pattern formation has been investigated based on many PDEs, discrete models on aquatic systems can provide more complex dynamics. A discrete toxic-phytoplankton–zooplankton model is studied in this paper, with the consideration of Allee effect and cross-diffusion. Focusing on Allee effect coefficient, flip and Neimark–Sacker bifurcation analyses are carried out. And focusing on cross-diffusion coefficient, Turing bifurcation analyses are carried out. Parameter conditions and bifurcation diagram of these bifurcations are obtained correspondingly. Numerical simulations are then performed which are consistent with results of theoretical analysis. Irregular patterns can be formed by flip bifurcation. Spirals can be formed by Neimark–Sacker bifurcation. Spots and stripes can be formed by Turing bifurcation. When Turing and flip, or Turing and Neimark–Sacker bifurcations both occur, special patterns can be obtained. [ABSTRACT FROM AUTHOR]

Radial Plastic Flow Machining (RPFM) is a novel severe plastic deformation process. By designing a specific plastic flow channel, the material is allowed to flow radially into the predetermined channel under the combined action of extrusion and cutting. A restricting ring is placed in the channel to form a copper terminal structure in one step. This study investigates in detail the formation mechanism, mechanical properties, and thermal stability of gradient structured copper terminals generated under different extrusion angles. It was found that as the extrusion angle increased, the high strain region slightly decreased, while the low strain region increased, allowing more material to be radially extruded. This indicates that tensile strength and toughness can be balanced by controlling different extrusion angle parameters. In performance testing, the study showed that the hardness of the copper terminals prepared by RPFM was more than double that of the original copper material, and the maximum tensile strength also doubled. Moreover, the performance of the copper terminals annealed at 150 ∘ C was similar to that of untreated copper terminals, demonstrating good thermal stability at this temperature. The study suggests that RPFM is not only an effective process for manufacturing gradient structured copper terminals in one step, but it also provides a new method for manufacturing copper terminals with excellent comprehensive performance. • Introduced Radial Plastic Flow Machining (RPFM) as a severe plastic deformation process. • Achieved one-step fabrication of gradient-structured copper terminals via RPFM. • Balanced high and low strain zones through varying extrusion angles. • Demonstrated significant improvement in hardness and tensile strength of copper terminals. • Confirmed good thermal stability at 150 °C for RPFM-prepared terminals. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced polymer (CFRP) can be widely used to repair damaged plates in marine engineering equipment. To predict the fatigue life improvement by this repair, the stress intensity factor (SIF) of the cracked plate without/with repair is analyzed rigorously. Specifically, the SIF of a cracked plate without repair is analyzed and the error due to the finite element model (FEM) mesh is evaluated by comparing with the exact solution. By applying the same mesh having the same error, the exact SIF of the repaired plate is obtained in a convenient form. Fatigue experiments reveal that the same crack propagation parameters (C and m) can be applied for the unrepaired/repaired plates. Based on those, the prediction equation of fatigue life is obtained for cracked steel plates repaired with prestressed CFRP. The results show that this prediction method has the advantages of simplicity and efficiency. • The stress intensity factor (SIF) of an unrepaired/repaired cracked plate is investigated, and the convenient form of the exact SIF of the repaired plate is obtained by using the "proportional method". • It is found that crack expansion rates of unrepaired/repaired plates can be expressed by almost the same equations. • The correctness of prediction equation for prestressed-CFRP-repaired cracked steel plates is verified by fatigue test. • The enhancement effect of prestress on the fatigue life of cracked steel plate is quantitatively investigated. [ABSTRACT FROM AUTHOR]

Carbon-coated LiTi 2 (PO 4) 3 (LTP-1) was synthesized by sol-gel and in-situ coating method, with tannic acid as carbon source. To compare the electrochemical performance, LTP-2 and LTP-3 were synthesized by the same method with citric acid and lactic acid as carbon sources, respectively. After calcination, the amorphous carbon layers were coated on the surface of LiTi 2 (PO 4) 3 crystal. Carbon contents of all the samples were controlled around 9.0%. The primary particles of LTP-1 are 20–50 nm, which agglomerate into irregular micron-sized secondary particles. The primary particles of LTP-2 and LTP-3 are 60–100 nm. As anode in aqueous lithium-ion batteries (LIBs), LTP-1 presented high cyclic stability and rate performance. The initial discharge capacity of LTP-1 is 60.9 mAh·g−1 at rate of 10 C. After cycling for 1000 cycles, the capacity retention rate of LTP-1 is 72.8%. As for LTP-2 and LTP-3, the initial specific discharge capacity is 46.0 mAh·g−1 and 44.0 mAh·g−1, the corresponding capacity retention rates are 45.4% and 16.4%, respectively, with the same testing parameters. • In situ carbon-coated LiTi 2 (PO 4) 3 was obtained by sol-gel. • Tannic acid was used as carbon source. • The possible reasons for the capacity decay were revealed. [ABSTRACT FROM AUTHOR]

Abstract Thermoelastic stress analysis (TSA) can be used to determine the stress field of structures or materials under cyclic loadings through temperature under adiabatic conditions. So high-frequency cyclic loadings are considered as a fundamental condition. However, loading frequencies in many practical applications do not meet the adiabatic conditions. In order to improve the accuracy of TSA under low-frequency fatigue loadings, the non-adiabatic response in TSA was derived by combining the classical thermoelastic equation and heat conduction equation. This response was used to create a modified model that accounted for heat transfer and temperature distribution under low-frequency loading conditions. Otherwise, fatigue test and finite element method were used to evaluate the correctness of the modified model using epoxy resin material. The results showed that the temperature change obtained from the modified model were in good agreement with the experiment results. The modified model can effectively evaluate the structural stress under low-frequency fatigue loadings. [ABSTRACT FROM AUTHOR]

Hollow nanoboxes structure have raised great attention as microwave absorption materials on account of their ultralow density and large specific area. By introducing an adjustable interior cavity structure, the dielectric loss and microwave absorption performance were affected by the tunable complex permittivity and impedance matching was improved. In our study, hollow CoS2 nanoboxes with designable interspaces were successfully fabricated based on the surfactant-assisted solution method and followed by an in situ ion-exchange process. The structure, elemental compositions and morphology of the products were characterized by XRD, XPS, EDX, SEM and TEM, respectively. In addition, microwave absorption performance and the intrinsic mechanism are investigated in-depth. The paraffin-based composites with 20 wt.% filling contents exhibited superior microwave absorption capacities in view of both maximum reflection loss value (RLmax, −54.48 dB) and effective absorption bandwidth (EAB, below −10 dB, 6.0 GHz), which can be ascribed to unique hollow structure and good impedance matching. With these considerations in mind, this study provides a reference for the construction of high-performance microwave absorbers with unique hollow structure. [ABSTRACT FROM AUTHOR]

Background: As a phosphorylated protein, NOLC1 is mainly located in the nucleus and is highly expressed in a variety of tumors, participating in the regulation of cell proliferation and aging. This study further investigated the role of NOLC1 in colorectal cancer tumors, aiming to provide sufficient scientific evidence for the clinical treatment of colorectal cancer. Methods: We used TCGA, GEO, TNMplot, GEPIA, and other databases to explore the expression level of NOLC1 in colorectal cancer patients, as well as the correlation between the clinical characteristics of colorectal cancer patients and their expression, and conducted the prognostic analysis. Immunohistofluorescence (IHF) staining verified the analytical results. Subsequently, KEGG and GO enrichment analysis was used to identify the potential molecular mechanism of NOLC1 promoting the occurrence and development of colorectal cancer. The influence of NOLC1 expression on the immune microenvironment of colorectal cancer patients was further investigated using the TIMER database. GDSC database analysis was used to screen out possible anti-colorectal cancer drugs against NOLC1. Finally, we demonstrated the effect of NOLC1 on the activity and migration of colorectal cancer cells by Edu Cell proliferation assay and Wound Healing assay in vitro. Results: Our results suggest that NOLC1 is overexpressed in colorectal cancer, and that overexpression of NOLC1 is associated with relevant clinical features. NOLC1, as an independent risk factor affecting the prognosis of colorectal cancer patients, can lead to a poor prognosis of colorectal cancer. In addition, NOLC1 may be associated with MCM10, HELLS, NOC3L, and other genes through participating in Wnt signaling pathways and jointly regulate the occurrence and development of colorectal cancer under the influence of the tumor microenvironment and many other influencing factors. Related to NOLC1: Selumetinib, Imatinib, and targeted drugs such as Lapatinib have potential value in the clinical application of colorectal cancer. NOLC1 enhances the proliferation and migration of colorectal cancer cells. Conclusions: High expression of NOLC1 as an independent prognostic factor for survival in patients with colorectal cancer. NOLC1 enhances the proliferation and migration of colorectal cancer cells. Further studies and clinical trials are needed to confirm the role of NOLC1 in the development and progression of colorectal cancer. [ABSTRACT FROM AUTHOR]

Liver metastasis is a common cause of death in progressive colorectal cancer patients, but the molecular mechanisms remain unclear. Here, it is reported that a conserved and oxidative pentose phosphate pathway‐associated circular RNA, circNOLC1, plays a crucial role in colorectal cancer liver metastasis. It is found that circNOLC1 silencing reduces the oxidative pentose phosphate pathway‐related intermediate metabolites and elevates NADP+/NADPH ratio and intracellular ROS levels, thereby attenuating colorectal cancer cell proliferation, migration, and liver metastasis. circNOLC1 interacting with AZGP1 to activate mTOR/SREBP1 signaling, or sponging miR‐212‐5p to upregulate c‐Met expression, both of which can further induce G6PD to activate oxidative pentose phosphate pathway in colorectal cancer liver metastasis. Moreover, circNOLC1 is regulated by the transcription factor YY1 and specifically stabilized HuR induces its parental gene mRNA expression. The associations between circNOLC1 and these signaling molecules are validated in primary CRC and corresponding liver metastasis tissues. These findings reveal that circNOLC1 interacting with AZGP1 and circNOLC1/miR‐212‐5p/c‐Met axis plays a key role in oxidative pentose phosphate pathway‐mediated colorectal cancer liver metastasis, which may provide a novel target for precision medicine of colorectal cancer. [ABSTRACT FROM AUTHOR]

In order to ensure the reliable interruption of high voltage direct current circuit breaker (HVDC CB), the breaking test of HVDC CB plays an important role in its performance verification. In this paper, the interruption process of the HVDC CB is analyzed, and the equivalent requirements for the breaking test of HVDC CB are summarized. In the breaking test of high voltage and high current, the transient interruption voltage (TIV) duration is short, which leads to insufficient voltage stress. A new synthetic test circuit for testing the interruption performance of HVDC CBs is proposed, which can solve the problem of insufficient TIV duration caused by insufficient test capacity. Subsequently, the working principle of the test circuit is introduced in detail and the design method of the circuit parameters is given. The short‐circuit current breaking test simulation of HVDC CB is carried out. The simulation results fit most well with the results of actual test cases, which verifies the universality of this test method. Finally, a test platform is built to verify the principle of the test circuit. TIV rose to 2.5 kV compared to the predetermined system voltage of 1.67 kV during the test, which means that the key stress provided by the test circuit can meet the expected requirements. [ABSTRACT FROM AUTHOR]

• SA-Co/NC is obtained by wet chemical method combined pyrolysis process. • Theoretical calculations and experiments prove oxidase-like activity of SA-Co/NC. • A time-based visualization scheme for TAC detection is proposed. • TAC monitoring of skin care products is achieved by smartphone platform. Reactive oxygen species (ROS) are an important cause of oxidative skin aging and can be removed by adding some antioxidant ingredients to skin care products. However, total antioxidant capacity (TAC) assays generally require sophisticated laboratory equipment, which greatly limits their daily application. Fortunately, the adoption and development of portable smartphone platforms could promises to solve this challenge. Herein, we report a cobalt single atom-based portable smartphone platform which can realize dynamic-time visualization monitoring the TAC of skin care product. Theoretical calculations and specific experimental results show that single-atom cobalt catalysts (SA-Co/NC) present excellent oxidase-like activity and can effectively convert dissolved oxygen into strongly oxidizing reactive oxygen species. More interestingly, based on the unique sacrificial inhibition catalytic mechanism of ascorbic acid (AA), it can be combined with a portable smartphone platform to detect the TAC of real samples by fitting a time-color-concentration standard curve and recording the change of color RGB values during the reaction. Compared with the traditional scheme, this scheme is convenient, low cost, and can realize visual detection of mobile terminals. This work provides a new scheme for miniaturization, convenience and home-based of TAC detection. [ABSTRACT FROM AUTHOR]

Relation extraction, a fundamental task in natural language processing, aims to extract entity triples from unstructured data. These triples can then be used to build a knowledge graph. Recently, pre-training models that have learned prior semantic and syntactic knowledge, such as BERT and ERNIE, have enhanced the performance of relation extraction tasks. However, previous research has mainly focused on sequential or structural data alone, such as the shortest dependency path, ignoring the fact that fusing sequential and structural features may improve the classification performance. This study proposes a concise approach using the fused features for the relation extraction task. Firstly, for the sequential data, we verify in detail which of the generated representations can effectively improve the performance. Secondly, inspired by the pre-training task of next-sentence prediction, we propose a concise relation extraction approach based on the fusion of sequential and structural features using the pre-training model ERNIE. The experiments were conducted on the SemEval 2010 Task 8 dataset and the results show that the proposed method can improve the F1 value to 0.902. [ABSTRACT FROM AUTHOR]

The commitment and differentiation of human placental progenitor cytotrophoblast (CT) cells are crucial for a successful pregnancy, but the underlying mechanism remains poorly understood. Here, we identified the transcription factor (TF), specificity protein 6 (SP6), as a human species-specific trophoblast lineage TF expressed in human placental CT cells. Using pluripotent stem cells as a model, we demonstrated that SP6 controls CT generation and the establishment of trophoblast stem cells (TSCs) and identified msh homeobox 2 (MSX2) as the downstream effector in these events. Mechanistically, we showed that SP6 interacts with histone acetyltransferase P300 to alter the landscape of H3K27ac at targeted regulatory elements, thereby favoring transcriptional activation and facilitating CT cell fate decisions and TSC maintenance. Our results established SP6 as a regulator of the human trophoblast lineage and implied its role in placental development and the pathogenies of placental diseases. [Display omitted] • SP6 is a human species-specific trophoblast lineage transcription factor • SP6 interacts with trophoblast core transcription factors and epigenetic modifiers • SP6 determines cytotrophoblast generation and TSC establishment via MSX2 • SP6 interacts with P300 to alter the H3K27ac landscape at MSX2 loci Chen et al. demonstrated that SP6 is a trophoblast lineage TF specific to human species. It plays a role in controlling cytotrophoblast cell fate decisions and trophoblast stem cell maintenance by modifying the histone status at target sites, positioning this TF within the network of human placenta development. [ABSTRACT FROM AUTHOR]

The transverse magnetic field (TMF) contacts generate a magnetic field through the structure and apply electromagnetic force to the arc to drive the arc to move on the surface of the contact. When the arc rotates on the surface of the spiral-type TMF contact, it needs to continuously cross the slots in the surface, so that the current is transferred between the contact arms. The structure of the slot not only determines the magnitude of the electromagnetic force of the arc during its movement, but also directly affects the arc’s appearance and speed during its motion. At present, most researches on spiral-type TMF contacts focus on increasing the strength of TMF and enhancing the force on the arc, but there is little research on the influence of the arc’s appearance during the slot crossing process. In this article, two spiral-type TMF contact structures are selected for experiments, the appearance of the arc in the slot crossing process is studied and analyzed, and the arc characteristics in different slot crossing processes are summarized. It is found that the anode plasma jets can keep moving with low concentration, which plays an important role in the slot crossing process and the current breaking. [ABSTRACT FROM AUTHOR]

• By tuning the pyrolysis temperature, a Ni/NiO heterogeneous interface is generated, which exhibit synergistic effect in the process of maleic anhydride hydrogenation. • Design and synthesis a robust carbon-coated Ni nanocatalyst with Ni/NiO heterojunctions. • Ni@C catalyst efficiently convert maleic anhydride to γ-butyrolactone under mild conditions. • A high γ-butyrolactone yield of 99.89 % was obtained at 200 °C in 8 h reaction time. Core-shell Ni@C catalysts with a uniform grain size distribution were synthesised via a simple hydrothermal method followed by pyrolysis carbonisation, and their catalytic performance for the liquid-phase hydrogenation of maleic anhydride (MA) was investigated herein. When the pyrolysis temperature was 350 °C, the resulting Ni@C catalyst (Ni@C-350) possessed abundant Ni/NiO heterostructures and a carbon surface layer. Among the analysed catalysts, Ni@C-350 demonstrated the lowest apparent activation energy for the hydrogenation of C C bonds (Ea = 34.3 KJ/mol) and C O bonds (Ea = 65.18 KJ/mol), yielding an MA conversion of 100 % and a γ-butyrolactone (GBL) selectivity of 99.89 % under mild reaction conditions (200 °C, 3 MPa hydrogen pressure, and 0.05 g catalyst). Furthermore, the Ni@C-350 catalyst exhibited high stability, with the yield of GBL above 95 % after five consecutive usage cycles. Ni@C-350 significantly outperformed other previously reported catalysts for the liquid-phase hydrogenation of MA. [Display omitted] [ABSTRACT FROM AUTHOR]

Background In the Long-Acting Antiretroviral Treatment Enabling Trial 2 (LATTE-2) phase 2b study, long-acting (LA) injectable cabotegravir + rilpivirine dosed every 8 weeks (Q8W) or every 4 weeks (Q4W) demonstrated comparable efficacy with daily oral antiretroviral therapy (ART) through 96 weeks in ART-naive adults with human immunodeficiency virus type 1 (HIV-1). Here we report efficacy, tolerability, and safety of cabotegravir + rilpivirine LA over approximately 5 years. Methods After 20 weeks of oral cabotegravir + abacavir/lamivudine, participants were randomized to cabotegravir + rilpivirine LA Q8W or Q4W or continue oral ART through the 96-week maintenance period. In the extension period through week 256, participants continued their current LA regimen (randomized Q8W/Q4W groups) or switched from oral ART to Q8W or Q4W LA therapy (extension-switch groups). Endpoints assessed included proportion of participants with HIV-1 RNA <50 copies/mL (Snapshot algorithm) and adverse events (AEs). Results At week 256, 186 of 230 (81%) participants in randomized Q8W/Q4W groups and 41 of 44 (93%) participants in extension-switch groups had HIV-1 RNA <50 copies/mL. No protocol-defined virologic failures occurred after week 48. Injection wsite reactions infrequently resulted in discontinuation (4 [2%] and 1 [2%] participants in randomized Q8W/Q4W and extension-switch groups, respectively). Three participants in randomized Q8W/Q4W groups experienced drug-related serious AEs, including 1 fatal serious AE (Q4W group); none occurred in extension-switch groups. Of 25 participants with AEs leading to withdrawal, 20 were in the randomized Q4W group; no AE leading to withdrawal occurred in >1 participant. Conclusions Cabotegravir + rilpivirine LA exhibited long-term efficacy and tolerability, demonstrating its durability as maintenance therapy for HIV-1 infection. Clinical Trials Registration. NCT02120352. [ABSTRACT FROM AUTHOR]

Repeated deformation or extended time is generally required in producing ultrafine grained structures, while this applies equally to forming gradient structures with ultrafine grains, which have been developed to evade the strength-ductility trade-off in recent years. This paper reports multiple shearing assisted fabrication of gradient-structured (GS) aluminium disks involving ultrafine grain formation in one step through a new process, called radial extrusion machining (REM). Finite element analysis and microstructural observations revealed that REM introduced multiple shearing, which provided hierarchical combinations of shear effects of different origins, intensities, and ranges of influence, resulting in a structural gradient across the disk thickness. The fabricated GS disks exhibited significant refinement of grains from ∼100 µm to submicron scale in the large-strained layers, which is attributable to the promoted multiple shearing. It was demonstrated that the grain refinement process is accelerated with the evolution of mutually crossing deformation or microshear bands introduced by multiple shearing. The operating structural mechanisms responsible for the dynamic formation of new grains were discussed in detail. This study provides a feasible method to fabricate GS disks with ultrafine grains formed in a straightforward and time-efficient way, and offers insights and guidance to develop new processes by introducing multiple shearing. [Display omitted] [ABSTRACT FROM AUTHOR]

Extrusion machining (EM) is an efficient and convenient method to prepare ultrafine-grained (UFG) materials. As a vital parameter in the EM process, tool rake angle (α) is critical to control the material's shear strain and grain size. The grains tend to refine with decreasing α , whereas a small α leads to difficult cutting, chip breakage, and poor surface quality. To achieve the controllable strain distribution, grain size adjustment, and improved formability of UFG pure copper strips, this paper proposed a novel design of the variable rake angle (VRA) tool. Combining experiments and finite element simulation, extrusion machining with variable rake angle tools (VRA-EM) was investigated. The results implied that a deviating angle (β) for the material flow existed during VRA-EM. The β increased as the cutting thickness (t c) increased, resulting in decreased plastic deformation, strain, and microhardness. The microstructure was also characterized by electron backscatter diffraction system (EBSD) and transmission electron microscopy (TEM) techniques. A dead metal zone was formed using the VRA tool, in which the material flow behavior was quite weak. The obtained UFG strip was further divided into the low-strain zone (LSZ) and high-strain zone (HSZ) based on strain distribution. And a new theoretical model of shear strain was established and conformed to experimental values. Accordingly, VRA-EM process was able to improve the mechanical properties and strain controllability, showing promising prospects for efficiently fabricating UFG materials. • A novel design of the variable rake angle (VRA) tool was proposed. • VRA-EM could achieve controllable strain distribution and grain size adjustment of UFG pure copper strips. • A deviating angle and a dead metal zone were formed during the VRA-EM. • The shear strain theoretical model of VRA-EM was established. [ABSTRACT FROM AUTHOR]

[Display omitted] • A colorimetric fluorescent probe was designed and synthesized for the detection of bisulfite with high sensitivity and selectivity in 100% aqueous solution. • The probe has been successfully used for the detection of SO 2 in food and animal serum samples with good recovery. • The probe was used as a solid sensor to visually detect the liquid and gas sulfur dioxide on the test strips. • The probe could detect both bisulfite in food and gaseous SO 2 in the environment. Bisulfite (HSO 3 −) has the functions of bleaching, antiseptic, antioxidant, inhibiting bacterial growth, and controlling enzymatic reactions in food. However, long-term consumption of foods containing excessive amounts of bisulfite can be harmful to health. In addition, large doses of sulfur dioxide (SO 2) can cause diarrhea, hypotension, allergic and asthmatic reactions in susceptible individuals. Therefore, it is urgent and essential to explore some rapid, reliable, and convenient tools to detect HSO 3 − in food and SO 2 gas. Herein, we exploited a fluorescent probe, NPO , to detect HSO 3 − in 100 % aqueous solution. The probe has the advantages of easy synthesis, excellent water solubility, significant colorimetric change, good selectivity, high sensitivity, and fast response (within 1 min). Probe NPO was successfully applied for testing strips to visualize the behavior of HSO 3 − and SO 2 gas. Moreover, the probe has been used to monitor the behavior of HSO 3 − in real food samples and animal serum samples. [ABSTRACT FROM AUTHOR]