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Intelligent condition identification is the development trend of transformer condition recognition, However, the existing intelligent condition recognition has the disadvantage of single model and low recognition accuracy. In order to overcome the disadvantage, a transformer condition recognition method based on dissolved gas analysis features selection and multiple models fusion is proposed. At first, artificial bee colony (ABC) algorithm is employed to select a set of optimal dissolved gas analysis (DGA) features. Then, according to the selected feature set, support vector classifier (SVC) model, naive bayes classifier (NBC) model, and back-propagation neural network (BPNN) model are respectively established. Finally, the Dempster–Shafer​ (D-S) evidence theory is used to combine the output results of the three recognition models. The identification performances of the optimal DGA features set and the multiple models fusion are evaluated. The results reveal that the proposed method has the highest accuracy and consistency of 89.39% and 90.49% respectively. With the input vector of proposed optimal DGA features set, the overall performance of multiple model fusion method is superior than the SVC, NBC, BPNN, extreme learning machine (ELM) and K- Nearest-Neighbor (KNN). The accuracy and consistency are increased by 4.54%, 4.52%, and 10.42%, 14.68%, and 3.03%, 3.67%, and 10.6%, 13.45%, and 24.24%, 27.57% respectively. Also, the overall performance of multiple model fusion method with optimal DGA features set is increased significantly compared to multiple model fusion method with IEC Ratio, Rogers Ratio, Doernenburg Ratio, optimal DGA features set selected by particle swarm optimization (PSO) and harris hawks optimization (HHO). The accuracy and consistency are increased by 4.54%, 7.43%, and 6.06%, 7.33%, and 10.6%, 13.58%, and 1.51%, 1.39%, and 9.09%,10% respectively. This proves the effectiveness and the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

Explanation: A systematic research on chronology, mineral compositions, geochemistry, particularly the rare earth elements of the SSZK1 well suggests that the YX-2300 coral bone formed at 114 ka have obvious positive Eu anomalies (A), and the model calculations suggest that at least 0.1% of hydrothermal fluids were added to the surrounding seawater during its growth (B and C). [Display omitted] • The environment of most coral samples in this study can be well judged as the marine environment with oxidation conditions. • The similarity in the distribution patterns of REE+Y in P1 and P2 suggests that diagenetic alteration has little influence. • Obvious positive Eu anomalies and the REE + Y distribution model indicate the involvement of hydrothermal fluids. Coral reefs play an important role in the high-resolution paleoclimate and paleoenvironment records. In particular, the contents, distribution patterns and elemental anomalies of the rare earth elements can reflect the paleoceanic conditions and sedimentary environments. In this study, we focus on the SSZK1 core in the Coral Reef of Yongxing Island, South China Sea (SCS). The sediments of this core can be divided into two stages: P1 (18.00–24.95 m) and P2 (24.95–55.92 m), based on the dating results. The results show that the coral reefs of P1 and P2 stages have slightly different REE contents, but similar REE + Y patterns. In general, the REE + Y patterns of both P1 and P2 stages are similar to those of normal marine carbonates (rocks), showing LREE depletion, negative Ce anomaly and high Y/Ho ratios. This indicates that the REEs of coral preserved their pristine geochemical features although they have experienced the diagenetic alteration to some degree. However, the samples, such as the YX-2300 coral bone formed at 114 ka, have obvious positive Eu anomalies except the similar REE + Y characteristics as the normal marine carbonates (rocks). The positive Eu anomalies indicate that some hydrothermal fluids may be input into the surrounding water at the time of coral bone formation. Based on the model calculations, at least 0.1% of hydrothermal fluids were added to the surrounding seawater during the growth of YX-2300 coral bone. By comparing the data and ages, it is suggested that these hydrothermal fluids could be associated with volcanic activities on Gaojishi Island or Hainan Island. This evidence is important to trace the occurrence of modern worldwide volcanism or deep faults activity in the deep-sea. [ABSTRACT FROM AUTHOR]

The application of metal-polymer structures has been restricted by challenges in achieving effective bonding between the two materials. To address this, nano-TiO 2 coatings were introduced to improve the interfacial bonding between the treated 6061 Al alloy and carbon fiber-reinforced thermoplastic composite (CFRTP) during the laser joining process. The results highlighted that the joints created with nano-TiO 2 coatings achieved significantly higher tensile shear force and strength, reaching 1.43 and 1.37 times the values of those without particles, respectively. This improvement can be attributed to the following factors: firstly, the incorporation of coatings led to an increase in the absorption of hydroxy groups, thereby improving the wettability of the Al alloy, which in turn promoted the formation of hydrogen bonds at the interface. Secondly, the increased surface roughness favored the chemical interaction between the Al alloy and CFRTP, ascribed to the enlarged contact area. Moreover, this change influenced the thermal contact conductance (TCC), thereby changing the temperature at the interface and joining areas of the two materials. Finally, a notable transformation in the failure mode was observed, transitioning from adhesive failure to cohesive failure when compared to joints without nano-TiO 2 coatings. This underscored the reinforcing role played by nano-TiO 2 particles, providing an innovative solution for enhancing the interface bonding between dissimilar materials. [ABSTRACT FROM AUTHOR]

The application of metal-polymer structures has been restricted by challenges in achieving effective bonding between the two materials. To address this, nano-TiO 2 coatings were introduced to improve the interfacial bonding between the treated 6061 Al alloy and carbon fiber-reinforced thermoplastic composite (CFRTP) during the laser joining process. The results highlighted that the joints created with nano-TiO 2 coatings achieved significantly higher tensile shear force and strength, reaching 1.43 and 1.37 times the values of those without particles, respectively. This improvement can be attributed to the following factors: firstly, the incorporation of coatings led to an increase in the absorption of hydroxy groups, thereby improving the wettability of the Al alloy, which in turn promoted the formation of hydrogen bonds at the interface. Secondly, the increased surface roughness favored the chemical interaction between the Al alloy and CFRTP, ascribed to the enlarged contact area. Moreover, this change influenced the thermal contact conductance (TCC), thereby changing the temperature at the interface and joining areas of the two materials. Finally, a notable transformation in the failure mode was observed, transitioning from adhesive failure to cohesive failure when compared to joints without nano-TiO 2 coatings. This underscored the reinforcing role played by nano-TiO 2 particles, providing an innovative solution for enhancing the interface bonding between dissimilar materials. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Leaf mass fraction (LMF) is mainly related to draught tolerance. • Leaf area ratio (LAR) is mainly related to light capture. • LMF and LAR play different roles in the acclimation of plants. Abstract Understanding how plants allocate biomass to different organs is of high importance since biomass allocation among organs determines many growth processes. Biomass allocation among plant organs is driven by environmental conditions, while functional traits can also be potential covariates to understand the allocation of biomass. However, the relationships between functional traits and biomass allocation remain poorly known and studied. We investigated the relationships of two biomass allocation indicators, including leaf mass fraction (LMF) and leaf area ratio (LAR), with six economic traits and five hydraulic traits across 30 woody species. We found that LMF and LAR showed different relationships with economics traits. In addition, a significantly negative correlation was observed between LMF and leaf water potential at turgor loss point (TLP), but no significant relationship was found between LAR and TLP. Principal component analyses showed that LMF-related traits and LAR-related traits could be divided into two groups. Taken together, LMF is mainly related to draught tolerance while LAR mainly related to light capture. Although LMF and LAR are two significantly correlated biomass allocation indicators, they play different roles in the acclimation of plants. Researchers should focus on the different functions of these two indicators and the different relationships with other functional traits in the further research. [ABSTRACT FROM AUTHOR]

Aluminum profile structures are extensively used in the transportation industry and pose a considerable challenge to single-sided spot joining technologies. The widely used Huck BOM® riveting process requires prefabricated holes and thus significantly increases cost and reduces efficiency. In this study, a novel single-sided friction riveting (SSFR) process with an internal-threaded semi-tubular rivet is proposed to realize a screwed-solid state hybrid joining of aluminum sheet to profile structure without prefabricated holes. The results show that the upper trapped metal is welded with the lower profile structure under the thermal-mechanical coupled action generated by rivet stirring. The internal thread could facilitate material filling into the rivet cavity and form a mechanical interlock, so as to realize the single-sided joining between the sheet and the profile without prefabricated holes. The one-stage SSFR process could form shear texture and promote continuous dynamic recrystallization, but lead to excessive material softening and internal cracking. A two-stage process including friction softening and screw tightening could better coordinate the effects of heat and force, thereby avoiding cracking and refining grains in the stirring zone. Finally, the tensile-shear and cross-tension peak loads were respectively improved by 9.0 % and 29.3 %, compared to the joints with one-stage process and non-structural rivet. [ABSTRACT FROM AUTHOR]

The much lower processing temperature makes cold spray have many merits to deposit metallic coatings, repair failed metallic parts and additively manufacture metallic parts as compared with the high-energy beam based metal depositing processes. Although adhesion is critical for coating and repairing applications for cold sprayed deposits, it is still challenging to get high bonding strength especially for depositing materials with low density and elastic modulus. Here we introduced an in-situ micro-forging (MF) effect to cold spray by mixing 200–300 µm big-sized 410 stainless steel shot peening particles into the depositing Al powder. Due to the in-situ forging by the shot peening particles with 100 time higher kinetic energy than the depositing Al particle, vortex-like material intermixing between the Al deposit and the AZ31BMg substrate is periodically formed along the deposit/substrate interface. Meanwhile, the greatly improved interfacial plastic deformation at the deposit/substrate interface remarkably promotes the breaking and segmentation of the native oxide scale on both the spraying particle surface and substrate surface which promotes metallurgical bonding formation across the deposit/substrate interface. Both the vortex-like material intermixing induced enhanced mechanical interlocking and the improved metallurgical bonding contribute to a higher adhesion. As a consequence, the adhesion of Al deposit increases from 47.9 MPa to 107.2 MPa. [Display omitted] • An in-situ micro-forging is introduced into cold spray to improve the adhesion. • Vortex-like material intermixing is periodically formed along the interface. • More dispersed interfacial oxide scale leads to improved metallurgical bonding fraction. • Adhesion of cold sprayed Al deposit is improved from 47.9 MPa to 107.2 MPa. [ABSTRACT FROM AUTHOR]

Landslides frequently block rivers, forming a barrier lake, resulting in a dam break event in the terrestrial environment. However, reports about the submarine landslides are scarce. Herein, the periplatform submarine landslides changing transport pathways of deepwater gravity flows within the southeastern region out of Xuande Atoll on the Xisha Islands, South China Sea, are described. Submarine landslides, including SL I and SL II, with a total area of 170.9 km2, were identified using up-to-date geophysical data, including multi-beam bathymetric and seismic data and sediment gravity cores. SL I directly connects the Sansha Canyon forming a large-scale negative relief with an area of 151.8 km2, developing the terraces, and transporting blocks and remnant blocks. SL II covers an area of 19.1 km2 and was mainly deposited on the deepwater plain with a toe part that is higher than the initial seafloor. The negative relief created by SL I on the seafloor forms the dominant pathways for the gravity flows, creating the new active channel system directly flowing into the canyon. The turbidity currents flowing along the steep lateral margin of SL II formed the cyclic steps. The remnant submarine landslide deposits on the western canyon margin indicate that SL I previously blocked the canyon and formed a submarine barrier lake, which was then eroded by the gravity flows flowing along with the channel system within SL I and the upstream canyon. Finally, the canyon was formed again, whose axis was "pushed" eastward by SL I. These observations update the evolution model of submarine landslide on a carbonate platform slope and the transport system from the slope to the submarine canyon or the deep basin and clarify the stability of submarine engineering and island-and-reef systems. • Our results help understand the initiation and emplacement processes of submarine landslides around the atoll. • Submarine landslides are the major conduits for shallow-water sediment transport into deep-water environments. • Submarine canyonning process can evacuate the distal part of a submarine landslide on the carbonate platform slope. [ABSTRACT FROM AUTHOR]

Accumulation of amyloid β protein (Aβ)-containing neuritic plaques in the brain is a neuropathological feature of Alzheimer's disease (AD). The β-site APP-cleaving enzyme 1 (BACE1) is essential for Aβ generation and dysregulation of BACE1 expression may lead to AD pathogenesis. Bcl-2-associated athanogen 1M (BAG-1M), initially identified as an anti-apoptotic protein, has also been found to be highly expressed in the same neurons that contain intracellular amyloid in the hippocampus of AD patient. In this report, we found that over-expression of BAG-1M enhances BACE1-mediated cleavage of amyloid precursor protein (APP) and Aβ production by up-regulating BACE1 gene transcription. The regulation of BACE1 transcription by BAG-1M was dependent on NF-κB, as BAG-1M complexes NF-κB at the promoter of BACE1 gene and co-activates NF-κB-facilitated BACE1 transcription. Moreover, expression of BAG-1M by lentiviral vector in the hippocampus of AD transgenic model mice promotes Aβ generation and formation of neuritic plaque, and subsequently accelerates memory deficits of the mice. These results provide evidence for an emerging role of BAG-1M in the regulation of BACE1 expression and AD pathogenesis and that targeting the BAG-1M-NF-κB complex may provide a mechanism for inhibiting Aβ production and plaque formation. [ABSTRACT FROM AUTHOR]

• A novel approach for enhancing bonding reliability of metal and CFRTP was proposed. • Synergetic mechanism of interfacial physical–chemical dual scales was elucidated. • The multiple modification approach enhanced the bonding reliability by 166%. • Oxide structures were confirmed as the condition of interfacial chemical bonding. • Hydrogen bonds were successfully induced and captured at the bonding interface. A novel multiple modification approach including laser texturing, micro-arc oxidation process and silane coupling agent treatment was proposed to optimize the bonding interface. Firstly, laser texturing was fabricated to promote the mechanical interlocking. Secondly, the micro-arc oxidation porous structure was designed to modify its physical structure and chemical states. This promoted the interfacial mechanical interlocking in dual scales including texturing and porous structures. Moreover, the new chemical bonds such as Ti-C and Ti-O were generated at the interface. The bonding strength of TC4/CFRTP was enhanced from 10.23 MPa to 23.41 MPa. Besides, more hydroxyl groups (–OH) were adsorbed inside the optimized structure, and the hydrogen bonds were successfully induced by silane coupling film via the final step. This further enhanced the bonding strength to the maximum of 27.22 MPa. Therefore, the multiple modification approach realized the comprehensive enhancement of mechanical interlocking, chemical bonding and functional groups interaction, which enhanced the bonding reliability by 166% than pretreated case. These results benefit future research in the process optimization to improve the reliability of metal-CFRTP bonding structures. [ABSTRACT FROM AUTHOR]

Increasing the cutoff voltage is efficient to increase the energy density of LiCoO 2 -based lithium-ion batteries to meet consumers' demand for electronic devices. However, higher cut-off voltage may lead to continuous decomposition of electrolyte and shorten the battery's cycle life. Herein, 1,3-propanediolcyclic sulfate (PCS) is designed as a film-forming additive to improve the electrochemical performance of high-voltage graphite/LiCoO 2 cells. The combined density functional theory (DFT) calculations and experimental results indicate that PCS participates in the film formation on both LiCoO 2 cathode and graphite anode side to regulate the interfacial reaction and inhibit the corresponding gas production. Thus, the capacity retention of 4.45 V graphite/LiCoO 2 pouch cells cycled at 45 °C after 300 cycles is elevated from 59.5% to 80.1% by incorporating 1.0 wt% PCS additive into the base electrolyte. It is found that PCS follows the C-O bond breaking mechanism on the positive electrode and S-O bond breaking mechanism on the negative electrode, respectively. In addition, PCS may undergo H-transfer reaction at the cathode in the first cycle because the -O-SO 2 - group appears as oxidation product in ex-situ X-ray photoelectron spectroscopy (XPS) results. This finding provides new insights for understanding the mechanism of PCS acting as a high-voltage additive. • PCS can participate in film formation on both electrodes. • PCS follows the C-O bond breaking mechanism to produce -O-SO 3 - species on LiCoO 2. • -O-SO 2 - is produced by PCS following the S-O bond breaking mechanism on graphite. • PCS can improve the high voltage performance of graphite/LiCoO 2 cells. [ABSTRACT FROM AUTHOR]

• Hybrid laser heat source was selected for repairing of hybrid laser welded A7N01 alloy. • Defects in original joints were effectively eliminated by hybrid laser heat source. • HCF property with a little increase can be obtained compared with original joints. As one of the key concerns in the health maintenance system for modern railway equipment, defect repair plays an important role in enhancing the running safety reliability and economic benefits. In this study, welding defects of A7N01 alloy commonly used in high-speed trains were repaired by hybrid laser welding. The surface integrity of the welded zone before and after repairing was evaluated by various characterization methods in terms of the microstructures, tensile and fatigue properties. The results show that the original incomplete penetration defects would be eliminated by welding repair, giving rise to some microstructural changes such as the grain refinement and the widening of fine grain zone in the original welded joints. The heat input during welding repairing induced significantly reduction of the hardness and tensile strength from 105 HV to 75 HV and from 358 MPa to 338 MPa, respectively. Nevertheless, the fatigue properties of hybrid welded A7N01 alloy with the hybrid welding repairing were improved by 33.8%, probably because of reduced defects. [ABSTRACT FROM AUTHOR]

Novel Y 3 NbO 7 nanowires were successfully synthesized by a facile hydrothermal method using Y(NO 3 ) 3 ·6H 2 O and Nb 2 O 5 as raw materials. X-ray power diffraction (XRD), High resolution transmission electron microscopy (HR-TEM), UV–vis diffuse reflectance spectroscopy (UV–vis-DRS), X-ray photoelectron spectroscopy (XPS) and Brunauer–Emmett–Teller (BET) techniques were employed to determine the structure, morphology, specific surface area and optical properties of the as-prepared samples. Photocatalytic examination of the samples was carried out using aqueous solution of omeprazole sodium under visible light irradiation. The effects of initial omeprazole sodium concentration and catalyst amount on the photocatalytic degradation were also investigated. Detailed characterization demonstrated that Y 3 NbO 7 nanowires have cubic fluorite crystal structure with a diameter of about 20 nm and a length up to several micrometers. Photocatalytic activity tests revealed that omeprazole sodium photocatalytic reactions followed pseudo-first-order kinetics and Y 3 NbO 7 nanowires exhibited greater photocatalytic activity than its bulk counterparts. [ABSTRACT FROM AUTHOR]