Slope stability analysis is a classical mechanical problem in geotechnical engineering and engineering *** is of great significance to study the stability evolution of expansive soil slopes for engineering constructio...
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Slope stability analysis is a classical mechanical problem in geotechnical engineering and engineering *** is of great significance to study the stability evolution of expansive soil slopes for engineering construction in expansive soil *** of the existing studies evaluate the slope stability by analyzing the limit equilibrium state of the slope,and the analysis method for the stability evolution considering the damage softening of the shear zone is *** this study,the large deformation shear mechanical behavior of expansive soil was investigated by ring shear *** damage softening characteristic of expansive soil in the shear zone was analyzed,and a shear damage model reflecting the damage softening behavior of expansive soil was derived based on the damage ***,by skillfully combining the vector sum method and the shear damage model,an analysis method for the stability evolution of the expansive soil slope considering the shear zone damage softening was *** results show that the shear zone subjected to large displacement shear deformation exhibits an obvious damage softening *** damage variable equation based on the logistic function can be well used to describe the shear damage characteristics of expansive soil,and the proposed shear damage model is in good agreement with the ring shear test *** vector sum method considering the damage softening behavior of the shear zone can be well applied to analyze the stability evolution characteristics of the expansive soil *** stability factor of the expansive soil slope decreases with the increase of shear displacement,showing an obvious progressive failure behavior.
Surface electromyogram(sEMG)serves as a means to discern human movement intentions,achieved by applying epidermal electrodes to specific body ***,it is difficult to obtain high-fidelity sEMG recordings in areas with i...
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Surface electromyogram(sEMG)serves as a means to discern human movement intentions,achieved by applying epidermal electrodes to specific body ***,it is difficult to obtain high-fidelity sEMG recordings in areas with intricate curved surfaces,such as the body,because regular sEMG electrodes have stiff *** this study,we developed myoelectrically sensitive hydrogels via 3D printing and integrated them into a stretchable,flexible,and high-density sEMG electrodes *** electrode array offered a series of excellent human-machine interface(HMI)features,including conformal adherence to the skin,high electron-to-ion conductivity(and thus lower contact impedance),and sustained stability over extended *** attributes render our electrodes more conducive than commercial electrodes for long-term wearing and high-fidelity sEMG recording at complicated skin *** in vivo studies were used to investigate its efficacy to control a prosthetic hand by decoding sEMG signals from the human hand via a multiple-channel readout circuit and a sophisticated artificial intelligence *** findings demonstrate that the 3D printed gel myoelectric sensing system enables real-time and highly precise control of a prosthetic hand.
High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the...
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High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.
The discovery of phase changings in two-dimensional(2D)materials driven by external stimuli not only helps to understand the various intriguing phases in 2D materials but also provides directions for constructing new ...
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The discovery of phase changings in two-dimensional(2D)materials driven by external stimuli not only helps to understand the various intriguing phases in 2D materials but also provides directions for constructing new functional ***,by combining angle-resolved photoemission spectroscopy(ARPES)and in-situ alkali-metal deposition,we studied how alkali-metal adatoms affect the electronic structure of T_(d)-WTe_(2)on two different cleaved *** found that depending on the polarization direction of the cleaved surface,the alkali-metal deposition triggered two successive phase transitions on one surface of WTe_(2),while on the other surface,no phase transition was *** attributed the observed phase transitions to a Td↑-1T′-Td↓structural transition driven by an alkali-metal induced sliding of *** comparing the band structure obtained in different structural phases of WTe_(2),we found that the evolution of band structure across different phases is characterized by an energy scale that could be related to the degree of orbital hybridization between two adjacent WTe_(2)*** results demonstrate a method that manipulates the surface structure of bulk 2D *** also builds a direct correlation between the electronic structure and the degree of interlayer misalignment in this intriguing 2D material.
This study improves ship classification in Synthetic Aperture Radar (SAR) imagery, focusing on few-shot datasets. We propose a data augmentation strategy combining the AlignMixup method and a detail enhancement module...
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This study improves ship classification in Synthetic Aperture Radar (SAR) imagery, focusing on few-shot datasets. We propose a data augmentation strategy combining the AlignMixup method and a detail enhancement module to optimize convolutional neural network performance. AlignMixup integrates features at intermediate layers, capturing structural information, while the detail enhancement module highlights high-frequency details to improve ship feature recognition in SAR images. Experiments on small sample datasets show that our method increases classification accuracy by a significant margin and remains practical under data-limited conditions.
Ternesite has been proven to have significant competitiveness as an ultralow lime CO2 sequestration binder. It is worthy of industrial production for CO2 emission reduction in the cement industry. MgO is inevitable in...
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Ternesite has been proven to have significant competitiveness as an ultralow lime CO2 sequestration binder. It is worthy of industrial production for CO2 emission reduction in the cement industry. MgO is inevitable in natural limestone, which may change ternesite's sintering and carbonation properties. This study aims to simulate the effect of MgO content on the sintering and carbonation behavior of ternesite. The results show that less than 4% Mg2+ is dissolved in the crystal structure of ternesite by replacing Ca2+ and induces a reduction of cell size. More than 4% MgO will be sintered to form bredigite and merwinite, restraining ternesite content in clinkers. The compressive strength of ternesite clinker compacts is negatively correlated with the MgO doping content. The increase in MgO doping from 0 to 20% resulted in a 68.2% decrease in compressive strength. MgO doping less than or equal to 3% improves the CO2 sequestration capacity of ternesite clinkers by 4.1%;however, more than or equal to 5% will reduce the CO2 sequestration capacity. The analysis of carbonation products showed that MgO reduced the content of aragonite and vaterite and induced the formation of magnesian calcite and monohydrocalcite. The difference in ternesite content, crystal morphology, and carbonation products is the reason for the change in carbonation properties of MgO-doped clinkers.
Performance degradation in solid oxide fuel cells (SOFCs) leads to shorter service life and unexpected downtime. To reduce economic losses and accelerate commercialization, accurately predicting the degradation is con...
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Performance degradation in solid oxide fuel cells (SOFCs) leads to shorter service life and unexpected downtime. To reduce economic losses and accelerate commercialization, accurately predicting the degradation is conducted in this study. First, a comprehensive analysis of performance degradation through experiments on a real SOFC system is investigated. Then, three dada-driven robust models, that is, vector autoregressive moving average (VARMA), radial basis function neural network (RBFNN), and neural basis expansion analysis for time series (N-BEATS) models are proposed to predict the SOFC's performance degradation. Herein, the top 60-90% of the experimental datasets are used for training and the bottom 40-10% for testing. After training, the prediction performance testing of these 3 models is compared with that of the bi-long short-term memory networks (bi-LSTM) and bi-gated recurrent units (bi-GRU) models. Simulation results show that both the VARMA and N-BEATS models are superior to the bi-LSTM and bi-GRU models in predicting the performance degradation of the SOFC. While the test performance of the RBFNN model is worst, especially under the top 60% training datasets condition. These indicate it is feasible to respectively establish the VARMA model and the N-BEATS model for predicting the SOFC's performance degradation.
Dimethyl ether (DME) carbonylation to methyl acetate (MA) is a key intermediate step in ethanol synthesis. H-form mordenite (HMOR) efficiently catalyzes this reaction, with Br & oslash;nsted acid sites (BASs) serv...
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Dimethyl ether (DME) carbonylation to methyl acetate (MA) is a key intermediate step in ethanol synthesis. H-form mordenite (HMOR) efficiently catalyzes this reaction, with Br & oslash;nsted acid sites (BASs) serving as the active sites. The catalytic performance strongly depends on the strength of BASs. Modification of zeolites with extraframework species is a common method to tune acid strength, among which three-coordinated Al can generate superacid sites by synergistically interacting with Br & oslash;nsted acid sites. In this study, we employed an ion-exchange method to introduce three-coordinated Al in MOR and systematically investigated their effect on DME carbonylation. 31P MAS NMR spectra confirmed that the interaction between three-coordinated Al and BASs led to the formation of superacidic sites. Reactivity results showed that although the total number of BASs decreased after the introduction of three-coordinated Al, the catalytic performance improved significantly, with a 40% increase in the space-time yield of methyl acetate (STYMA). Mechanistic studies further revealed that these superacidic BASs facilitate the DME dissociation step, accounting for the enhanced activity. These findings provide a systematic strategy for effectively regulating BAS strength in zeolites and offer valuable insights into the rational design and optimization of zeolite catalysts for important industrialized processes.
The damping performance of Fe_(83)Ga_(17) alloys has been investigated in the static magnetic field (H). The results demonstrate that the damping peak value can be adjusted between 0.020 and 0.085 under the magnetic f...
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The damping performance of Fe_(83)Ga_(17) alloys has been investigated in the static magnetic field (H). The results demonstrate that the damping peak value can be adjusted between 0.020 and 0.085 under the magnetic field and reaches a maximum at the critical magnetic field (H_(cr)=0.2 m T). As H is less than H_(cr).
Pesticide adjuvants,as crop protection products,have been widely used to reduce drift loss and improve utilization efficiency by regulating droplet ***,the coordinated regulation mechanisms of adjuvants and nozzles on...
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Pesticide adjuvants,as crop protection products,have been widely used to reduce drift loss and improve utilization efficiency by regulating droplet ***,the coordinated regulation mechanisms of adjuvants and nozzles on droplet spectrum remain ***,we established the relationship between droplet spectrum evolution and liquid atomization by investigating the typical characteristics of droplet diameter distribution near the *** on this,the regulation mechanisms of distinctive pesticide adjuvants on droplet spectrum were clarified,and the corresponding drift reduction performances were quantitively evaluated by wind tunnel *** shows that the droplet diameter firstly shifts to the smaller due to the liquid sheet breakup and then prefers to increase caused by droplet *** the surface tension of sprayed liquid facilitates the uniform liquid breakup and increasing the viscosity inhibits the liquid deformation,which prolong the atomization process and effectively improve the droplet *** a result,the drift losses of flat-fan and hollow cone nozzles are reduced by about 50%after adding organosilicon and vegetable oil *** contrast,the air induction nozzle shows a superior anti-drift ability,regardless of distinctive *** findings provide insights into rational adjuvant design and nozzle selection in the field application.
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