Laser-induced aerosols,predominantly submicron in size,pose significant environmental and health risks during the decommissioning of nuclear reactors.This study experimentally investigated the removal of laser-generat...Laser-induced aerosols,predominantly submicron in size,pose significant environmental and health risks during the decommissioning of nuclear reactors.This study experimentally investigated the removal of laser-generated aerosol particles using a water spray system integrated with an innovative system for pre-injecting electrically charged mist in our facility.To simulate aerosol generation in reactor decommissioning,a high-power laser was used to irradiate various materials(including stainless steel,carbon steel,and concrete),generating aerosol particles that were agglomerated with injected water mist and subsequently scavenged by water spray.Experimental results demonstrate enhanced aerosol removal via aerosol-mist agglomeration,with charged mist significantly improving particle capture by increasing wettability and size.The average improvements for the stainless steel,carbon steel,and concrete were 40%,44%,and 21%,respectively.The results of experiments using charged mist with different polarities(both positive and negative)and different surface coatings reveal that the dominant polarity of aerosols varies with the irradiated materials,influenced by their crystal structure and electron emission properties.Notably,surface coatings such as ZrO_(2)and CeO_(2)were found to possibly alter aerosol charging characteristics,thereby affecting aerosol removal efficiency with charged mist configurations.The innovative aerosol-mist agglomeration approach shows promise in mitigating radiation exposure,ensuring environmental safety,and reducing contaminated water during reactor dismantling.This study contributes critical knowledge for the development of advanced aerosol management strategies for nuclear reactor decommissioning.The understanding obtained in this work is also expected to be useful for various environmental and chemical engineering applications such as gas decontamination,air purification,and pollution control.展开更多
Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance to...Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance tomography enables real-time monitoring of changes in cerebral blood perfusion within the ischemic brain,but investigating the feasibility of using this method to assess post-stroke rehabilitation in vivo remains critical.In this study,ischemic stroke was induced in rats through middle cerebral artery occlusion surgery.Transcranial focused ultrasound stimulation was used to treat the rat model of ischemia,and electrical impedance tomography was used to measure impedance during both the acute stage of ischemia and the rehabilitation stage following the stimulation.Electrical impedance tomography results indicated that cerebral impedance increased after the onset of ischemia and decreased following transcranial focused ultrasound stimulation.Furthermore,the stimulation promoted motor function recovery,reduced cerebral infarction volume in the rat model of ischemic stroke,and induced the expression of brain-derived neurotrophic factor in the ischemic brain.Our results also revealed a significant correlation between the impedance of the ischemic brain post-intervention and improvements in behavioral scores and infarct volume.This study shows that daily administration of transcranial focused ultrasound stimulation for 20 minutes to the ischemic hemisphere 24 hours after cerebral ischemia enhanced motor recovery in a rat model of ischemia.Additionally,our findings indicate that electrical impedance tomography can serve as a valuable tool for quantitatively evaluating rehabilitation after ischemic stroke in vivo.These findings suggest the feasibility of using impedance data collected via electrical impedance tomography to clinically assess the effects of rehabilitatory interventions for patients with ischemic stroke.展开更多
The major aim of stroke therapy is to stimulate brain repair and improve behavioral recovery after cerebral ischemia.One option is to stimulate endogenous neurogenesis in the subventricular zone and direct the newly f...The major aim of stroke therapy is to stimulate brain repair and improve behavioral recovery after cerebral ischemia.One option is to stimulate endogenous neurogenesis in the subventricular zone and direct the newly formed neurons to the damaged area.However,only a small percentage of these neurons survive,and many do not reach the damaged area,possibly because the corpus callosum impedes the migration of subventricular zone-derived stem cells into the lesioned cortex.A second major obstacle to stem cell therapy is the strong inflammatory reaction induced by cerebral ischemia,whereby the associated phagocytic activity of brain macrophages removes both therapeutic cells and/or cell-based drug carriers.To address these issues,neurogenesis was electrically stimulated in the subventricular zone,followed by isolation of proliferating cells,including newly formed neurons,which were subsequently mixed with a nutritional hydrogel.This mixture was then transferred to the stroke cavity of day 14 post-stroke mice.We found that the performance of the treated animals improved in behavioral tests,including novel object,open field,hole board,grooming,and“time-to-feel”adhesive tape tests.Furthermore,immunostaining revealed that the stem cell marker nestin,the neuroepithelial marker Mash1,and the immature neuronal marker doublecortin-positive cells survived in the transplanted area for 2 weeks,possibly due to reduced phagocytic activity and supportive angiogenesis.These results clearly indicate that the transplantation of committed subventricular zone stem cells combined with a protective nutritional gel directly into the infarct cavity after the peak of stroke-induced neuroinflammation represents a feasible approach to improve neurorestoration after cerebral ischemia.展开更多
提出一种改进的ELECTRE(elimination et choix traduisant la réalité)动态模糊多属性决策方法。首先,对动态决策矩阵运用熵权法获得客观的时间权重;其次,提出改进的ELECTRE方法,针对直觉模糊数不可直接比较的问题,根据隶属...提出一种改进的ELECTRE(elimination et choix traduisant la réalité)动态模糊多属性决策方法。首先,对动态决策矩阵运用熵权法获得客观的时间权重;其次,提出改进的ELECTRE方法,针对直觉模糊数不可直接比较的问题,根据隶属度、非隶属度值不同的物理含义,分别构造其级别优先的一致性和矛盾性动态指标函数,再融合为各属性的一致性和矛盾性动态指标;随后,根据其相反的赋值意义,利用时间权重分别进行集成,获得综合各时间段的一致性和矛盾性指标并进行耦合,从而得到各方案的赋值级别优先关系,最终完成方案排序。实验数据验证了方法的有效性与可行性。展开更多
Transcutaneous electrical acupoint stimulation(TEAS)is a kind of physical therapy that use electric cur-rent through the electrodes placed on the surface of acupoints to produce clinical effects in the human body,whic...Transcutaneous electrical acupoint stimulation(TEAS)is a kind of physical therapy that use electric cur-rent through the electrodes placed on the surface of acupoints to produce clinical effects in the human body,which is characterized by less adverse reaction and convenient operation.It has been widely used in the treatment of various diseases.This review introduces six major clinical applications of TEAS,named analgesia,regulation of gastrointestinal function,improvement of reproductive function,enhancement of cognitive function,promotion of limb function recovery and relief of fatigue.Besides,TEAS has been ap-plied to the treatment of other chronic diseases such as hypertension and diabetes,achieving satisfactory clinical effects.However,two crucial challenges are encountered in the development of TEAS.One is the lack of standardization in the selection of parameters such as waveform,frequency,intensity and stimula-tion duration.The other is the limitation on the flexibility in the acupoint selection.This review analyzes key issues that need to be addressed in the current clinical application of TEAS,such as the selection of parameters and acupoints,and this review provides a certain reference value for optimizing regimens of TEAS and promoting its development and application.展开更多
Thermally conductive papers with electrical insulation and mechanical robustness are essential for efficient thermal management in modern electronics.In this study,we introduced a metal ion-assisted interfacial crossl...Thermally conductive papers with electrical insulation and mechanical robustness are essential for efficient thermal management in modern electronics.In this study,we introduced a metal ion-assisted interfacial crosslinking strategy to strengthen sugarfunctionalized graphene fluoride(SGF)and cellulose nanofibers(CNF)by hydrogen bonding and metal ion crosslinking that leads to simultaneous enhancements in thermal conductivity and mechanical properties.The facile sugarassisted ball-milling exfoliation method was developed to achieve the exfoliation of graphite fluoride and hydroxyl group functionalization on the surface of graphene fluoride.Thanks to the good dispersibility of the SGF sheets in water,the flexible SGF/CNF composite papers with hydrogen bonding were prepared via vacuum-assisted filtration.We introduced hydrogen bonding and metal ion crosslinking into SGF/CNF papers to obtain densely packed composite papers.Ca^(2+)or Al^(3+)ion-crosslinked SGF/CNF papers exhibited superior thermal and mechanical properties owing to hydrogen bonding and metal ion crosslinking.SGF/CNF-Ca^(2+)and SGF/CNF-Al^(3+)papers at 50 wt%of SGF yield in-plane thermal conductivities of 72.93 and 75.02 W m^(-1) K^(-1),and tensile strengths of 121.5 and 135.7 MPa,respectively.A thermal percolation value was observed at 12.6 vol%of SGF filler content.In addition,the SGF/CNF papers exhibited electrical insulation properties.These remarkable characteristics of the metal ion-crosslinked SGF/CNF papers are attributed to the densely packed structures caused by the strong interfacial interactions from hydrogen bonding as well as metal ion-crosslinking that could promote phonon transport.High-performance metal ion-crosslinked SGF/CNF papers with these fascinating advantages offer great potential for the thermal management of flexible electronics.展开更多
Aramid papers (AP), made of aramid fibers, demonstrate superiority in electrical insulation applications. Unfortunately, the strength and electrical insulating properties of AP remain suboptimal, primarily due to the ...Aramid papers (AP), made of aramid fibers, demonstrate superiority in electrical insulation applications. Unfortunately, the strength and electrical insulating properties of AP remain suboptimal, primarily due to the smooth surface and chemical inertness of aramid fibers. Herein, AP are modified via the nacre-mimetic structure composed of aramid nanofibers (ANF) and carbonylated basalt nanosheets (CBSNs). This is achieved by impregnating AP into an ANF-CBSNs (A-C) suspension containing a 3D ANF framework as the matrix and 2D CBSNs as fillers. The resultant biomimetic composite papers (AP/A-C composite papers) exhibit a layered “brick-and-mortar” structure, demonstrating superior mechanical and electrical insulating properties. Notably, the tensile strength and breakdown strength of AP/A-C5 composite papers reach 39.69 MPa and 22.04 kV mm^(−1), respectively, representing a 155 % and 85 % increase compared to those of the control AP. These impressive properties are accompanied with excellent volume resistivity, exceptional dielectric properties, impressive folding endurance, outstanding heat insulation, and remarkable flame retardance. The nacre-inspired strategy offers an effective approach for producing highly promising electrical insulating papers for advanced electrical equipment.展开更多
Karst fractures serve as crucial seepage channels and storage spaces for carbonate natural gas reservoirs,and electrical image logs are vital data for visualizing and characterizing such fractures.However,the conventi...Karst fractures serve as crucial seepage channels and storage spaces for carbonate natural gas reservoirs,and electrical image logs are vital data for visualizing and characterizing such fractures.However,the conventional approach of identifying fractures using electrical image logs predominantly relies on manual processes that are not only time-consuming but also highly subjective.In addition,the heterogeneity and strong dissolution tendency of karst carbonate reservoirs lead to complexity and variety in fracture geometry,which makes it difficult to accurately identify fractures.In this paper,the electrical image logs network(EILnet)da deep-learning-based intelligent semantic segmentation model with a selective attention mechanism and selective feature fusion moduledwas created to enable the intelligent identification and segmentation of different types of fractures through electrical logging images.Data from electrical image logs representing structural and induced fractures were first selected using the sliding window technique before image inpainting and data augmentation were implemented for these images to improve the generalizability of the model.Various image-processing tools,including the bilateral filter,Laplace operator,and Gaussian low-pass filter,were also applied to the electrical logging images to generate a multi-attribute dataset to help the model learn the semantic features of the fractures.The results demonstrated that the EILnet model outperforms mainstream deep-learning semantic segmentation models,such as Fully Convolutional Networks(FCN-8s),U-Net,and SegNet,for both the single-channel dataset and the multi-attribute dataset.The EILnet provided significant advantages for the single-channel dataset,and its mean intersection over union(MIoU)and pixel accuracy(PA)were 81.32%and 89.37%,respectively.In the case of the multi-attribute dataset,the identification capability of all models improved to varying degrees,with the EILnet achieving the highest MIoU and PA of 83.43%and 91.11%,respectively.Further,applying the EILnet model to various blind wells demonstrated its ability to provide reliable fracture identification,thereby indicating its promising potential applications.展开更多
Metal-organic frameworks(MOFs)have attracted significant interest as self-templates and precursors for the synthesis of carbon-based composites aimed at electromagnetic wave(EMW)absorption.However,the utilization of h...Metal-organic frameworks(MOFs)have attracted significant interest as self-templates and precursors for the synthesis of carbon-based composites aimed at electromagnetic wave(EMW)absorption.However,the utilization of high-temperature treatments has introduced uncertainties regarding the compositions and microstructures of resulting derivatives.Additionally,complete carbonization has led to diminished yields of the produced carbon composites,significantly limiting their practical applications.Consequently,the exploration of pristine MOF-based EMW absorbers presents an intriguing yet challenging endeavor,primarily due to inherently low electrical conductivity.In this study,we showcase the utilization of structurally robust Zr-MOFs as scaffolds to build highly conductive Zr-MOF/PPy composites via an inner-outer dual-modification approach,which involves the production of conducting polypyrrole(PPy)both within the confined nanoporous channels and the external surface of Zr-MOFs via post-synthetic modification.The interconnection of confined PPy and surface-lined PPy together leads to a consecutive and extensive conducting network to the maximum extent.This therefore entails outstanding conductivity up to~14.3 S cm^(-1) in Zr-MOF/PPy composites,which is approximately 1-2 orders of magnitude higher than that for conductive MOF nanocomposites constructed from either inner or outer modification.Benefiting from the strong and tunable conduction loss,as well as the induced dielectric polarization originated from the porous structures and MOF-polymer interfaces,Zr-MOF/PPy exhibits excellent microwave attenuation capabilities and a tunable absorption frequency range.Specifically,with only 15 wt.%loading,the minimum reflection loss(RLmin)can reach up to-67.4 dB,accompanied by an effective absorption bandwidth(EAB)extending to 6.74 GHz.Furthermore,the microwave absorption characteristics can be tailored from the C-band to the Ku-band by adjusting the loading of PPy.This work provides valuable insights into the fabrication of conductive MOF composites by presenting a straightforward pathway to enhance and reg-ulate electrical conduction in MOF-based nanocomposites,thus paving a way to facilely fabricate pristine MOF-based microwave absorbers.展开更多
BACKGROUND Although gastroscopy is a commonly used diagnostic and therapeutic technique,postoperative gastrointestinal dysfunction is prone to occur.Traditional Chinese medicine theory suggests that postoperative gast...BACKGROUND Although gastroscopy is a commonly used diagnostic and therapeutic technique,postoperative gastrointestinal dysfunction is prone to occur.Traditional Chinese medicine theory suggests that postoperative gastrointestinal disorders are related to spleen and stomach weakness.This study hypothesizes that the combination of acupoint application at the Ziwu Liuzhu acupoint and percutaneous acupoint electrical stimulation can promote postoperative gastrointestinal function recovery and alleviate stress reactions.AIM To investigate the effects of acupoint application of Ziwu Liuzhu combined with percutaneous acupoint electrical stimulation on postoperative gastrointestinal function recovery and stress response in patients undergoing gastrointestinal endoscopy surgery.METHODS A total of 120 patients who underwent gastroscopy surgery were selected and treated between October 2024 and January 2025.This study used a stratified block randomization method,and then allocated groups using computer-generated random number sequences(SAS 9.4 software).The groups were divided into two groups:A control group of 60 patients who received routine postoperative intervention measures,and an observation group of 60 patients who received acupuncture point application combined with transcutaneous acupoint electrical CONCLUSION The combination of percutaneous acupoint electrical stimulation in gastroscopy patients has been demonstrated to be both highly safe and effective.The benefits of this approach include the promotion of postoperative gastrointestinal function,the reduction of stress response,the attainment of optimal results,and the enhancement of patient satisfaction.展开更多
Electrical impedance tomography(EIT)is a non-invasive imaging modality that generates real-time images by measuring tissue bioimpedance.It works by applying current and collecting voltage data to reconstruct images of...Electrical impedance tomography(EIT)is a non-invasive imaging modality that generates real-time images by measuring tissue bioimpedance.It works by applying current and collecting voltage data to reconstruct images of electrical conductivity,refl ecting tissue properties.[1]We aim to off er a comprehensive guide to the fundamental technology behind EIT and to explore its clinical applications across both pulmonary and extrapulmonary domains.展开更多
The excellent mechanical properties make graphene promising for realizing nanomechanical resonators with high resonant frequencies,large quality factors,strong nonlinearities,and the capability to efectively interface...The excellent mechanical properties make graphene promising for realizing nanomechanical resonators with high resonant frequencies,large quality factors,strong nonlinearities,and the capability to efectively interface with various physical systems.Equipped with gate electrodes,it has been demonstrated that these exceptional device properties can be electrically manipulated,leading to a variety of nanomechanical/acoustic applications.Here,we review the recent progress of graphene nanomechanical resonators with a focus on their electrical tunability.First,we provide an overview of diferent graphene nanomechanical resonators,including their device structures,fabrication methods,and measurement setups.Then,the key mechanical properties of these devices,for example,resonant frequencies,nonlinearities,dissipations,and mode coupling mechanisms,are discussed,with their behaviors upon electrical gating being highlighted.After that,various potential classical/quantum applications based on these graphene nanomechanical resonators are reviewed.Finally,we briefy discuss challenges and opportunities in this feld to ofer future prospects for the ongoing studies on graphene nanomechanical resonators.展开更多
Self-designed Al8Si0.4Mg0.4Fe aluminium alloy was modified with Sr,followed by solid solution and aging treatments to regulate its microstructure and mechanical/electrical properties.The results show that after the mo...Self-designed Al8Si0.4Mg0.4Fe aluminium alloy was modified with Sr,followed by solid solution and aging treatments to regulate its microstructure and mechanical/electrical properties.The results show that after the modification treatment,the room-temperature tensile strength of the alloy remains nearly unchanged,the elongation at break slightly increases from 1.82%to 3.34%,and the electrical conductivity significantly increases from 40.1%international annealed copper standard(IACS)to 42.0%IACS.After the modification,the alloy was subjected to solid solution treatment at 515℃for 8 h,followed by aging treatment at 180,200,220 and 240℃for 6 h.With increasing aging temperature,the electrical conductivity increases monotonously from 41.4%IACS to 45.5%IACS,while the room-temperature tensile strength initially increases and then decreases.At 200℃,the alloy achieves an optimal balance between electrical conductivity and room-temperature tensile strength:the electrical conductivity is 42.5%IACS,and the room-temperature tensile strength is 282.9 MPa.When the aging temperature continues to rise,the alloy undergoes overaging.Although the conductivity continues to increase,the room-temperature tensile strength drops sharply,and it is only 177.1 MPa at 240℃.展开更多
The effects of drawing strain during intermediate annealing on the microstructure and properties of Cu-20 wt%Fe alloy wires while maintaining constant total deformation were investigated.Intermediate annealing effecti...The effects of drawing strain during intermediate annealing on the microstructure and properties of Cu-20 wt%Fe alloy wires while maintaining constant total deformation were investigated.Intermediate annealing effectively removes work hardening in both the Cu matrix and Fe fibers,restoring their plastic deformation capacity and preserving fiber continuity during subsequent redrawing.The process also refines the Fe phase,leading to a more uniform size distribution and straighter,better-aligned Cu/Fe phase interfaces,thereby enhancing the comprehensive properties of the alloy.The magnitude of drawing strain during intermediate annealing plays a critical role in balancing the mechanical strength and electrical conductivity of redrawn wires.A lower initial drawing strain requires greater redrawing strain,leading to excessive hardening of the Fe fibers,which negatively impacts the electrical conductivity and tensile plasticity.Conversely,a higher initial drawing strain can result in insufficient work hardening during the redrawing deformation process,yielding minimal strength improvements.Among the tested alloys,H/3.5 wires show a slight reduction in strength and hardness compared to W and H/4.5 wires but exhibit a significant increase in tensile elongation and electrical conductivity.The tensile strength was 755 MPa,and the electrical conductivity was 47%international-annealed copper standard(IACS).The optimal performance is attributed to the formation of a high-density,ultrafine Fe fiber structure-aligned parallel to the drawing direction,which is achieved through a suitable combination of the drawing process and intermediate annealing.展开更多
Fluorination is a critical surface modification technique for enhancing the electrical performance of composite insulators.This study employs molecular simulations to examine the microstructure and space charge behavi...Fluorination is a critical surface modification technique for enhancing the electrical performance of composite insulators.This study employs molecular simulations to examine the microstructure and space charge behavior of fluorinated and non-fluorinated silicone rubber under an electric field,with experimental validation.The results show that fluorinated silicone rubber exhibits lower total energy,higher polarization,and stronger dipole moments compared to its non-fluorinated counterpart,shifting the material from an insulating to a conductive state.Under lower electric field strengths,the carbon-silicon bonds in fluorinated silicone rubber are longer,but it maintains geometric stability under higher fields.The energy gap changes across different fluorination modes and varies with electric field strength,indicating that fluorination affects conductivity differently at various field intensities.Both fluorination methods improve conductivity in the 0–3.8 V/nm range,with substitutional fluorination showing superior performance between 3.8 and 8.9 V/nm.Above 9.1 V/nm,fluorination maximizes conductivity.The fluorinated samples exhibit a greater redshift at higher electric fields,resulting in enhanced conductivity and improved surface charge distribution.These findings offer insights into the microscopic effects of fluorination on silicone rubber’s electrical properties,while experiments confirm that fluorination increases hydrophobicity and boosts DC flashover voltage,further enhancing the material’s performance.展开更多
The integrated innovation of artificial intelligence and electrical automation technology not only represents a further innovation of traditional models but also promotes the innovative development of both artificial ...The integrated innovation of artificial intelligence and electrical automation technology not only represents a further innovation of traditional models but also promotes the innovative development of both artificial intelligence and electrical automation technology.This paper delves into the significance of the integrated innovative applications of artificial intelligence and electrical automation technology,as well as the strategies for such applications,aiming to better achieve the intelligent development of electrical automation technology.展开更多
Magnesium(Mg)alloys offer significant potential for conductive applications,thanks to their distinctive attributes,including high specific strength,excellent electrical conductivity(EC),low density,electromagnetic int...Magnesium(Mg)alloys offer significant potential for conductive applications,thanks to their distinctive attributes,including high specific strength,excellent electrical conductivity(EC),low density,electromagnetic interference shielding effectiveness(EMI SE),and recyclability.However,a major challenge in Mg alloy research is balancing high strength with good EC,as strengthening these alloys often compromises their EC.This paper offers an in-depth analysis of the mechanisms,strategies,and applications aimed at improving the EC of Mg alloys.A bibliometric study is performed to uncover the main research trends and emerging hotspots within the field.The review then examines various strategies to improve EC focusing on factors such as solute elements,second phases,grain boundaries,textures,and vacancies.By carefully controlling alloy composition and optimizing heat treatment processes,significant advancements have been achieved by researchers in developing Mg alloys that possess both high strength and high EC,especially in Mg-Al,Mg-Zn,Mg-RE alloy systems and composites.Finally,the paper outlines future research directions,stressing the importance of further exploration into alloying element selection,heat treatment optimization,and other advanced strategies.These efforts are crucial for overcoming current challenges and expanding the application of Mg alloys in EC fields.展开更多
Noise is inevitable in electrical capacitance tomography(ECT)measurements.This paper describes the influence of noise on ECT performance for measuring gas-solids fluidized bed characteristics.The noise distribution is...Noise is inevitable in electrical capacitance tomography(ECT)measurements.This paper describes the influence of noise on ECT performance for measuring gas-solids fluidized bed characteristics.The noise distribution is approximated by the Gaussian distribution and added to experimental capacitance data with various intensities.The equivalent signal strength(Ф)that equals the signal-to-noise ratio of packed beds is used to evaluate noise levels.Results show that the Pearson correlation coefficient,which indicates the similarity of solids fraction distributions over pixels,increases with Ф,and reconstructed images are more deteriorated at lower Ф.Nevertheless,relative errors for average solids fraction and bubble size in each frame are less sensitive to noise,attributed to noise compromise caused by the process of pixel values.These findings provide useful guidance for assessing the accuracy of ECT measurements of multiphase flows.展开更多
In this study,Al-xSi-0.3Mn-0.3Mg-0.14Fe alloys(x=6.5,7.5,8.5,wt.%)were prepared by super-slow-speed die-casting,and the effects of Si content on the microstructure,mechanical,and thermal/electrical conductivities in a...In this study,Al-xSi-0.3Mn-0.3Mg-0.14Fe alloys(x=6.5,7.5,8.5,wt.%)were prepared by super-slow-speed die-casting,and the effects of Si content on the microstructure,mechanical,and thermal/electrical conductivities in as-cast,T5,and T6 states(DIN EN 1706:2020)were investigated.It is found that the increase of Si content in the alloy enhances the formation of eutectic segregation band in the casting surface microstructure.Within the Si content range of 6.5%-8.5%,as a comprehensive evaluation criterion of mechanical properties,the quality index(QI)of 376.1 MPa can be obtained in the as-cast state of the alloy with about 7.5%Si content,373.4 MPa in T5 state of the alloy with 6.5%Si content,and 432.2 MPa in T6 state of the alloy containing 8.5%Si.The heat treatment state significantly affects the thermal conductivity and electrical conductivity of the alloys.The eutectic silicon in the alloy is segemented and further spheroidizaed during the solution process,and the solute atoms of Mg and Si are more adequately precipitated during the aging process.Both of these greatly reduce the probability of electron scattering.Thus,T6 treatment significantly improves the electrical and thermal conductivities.With the increase of Si content,both thermal conductivity and electrical conductivity decrease slightly,demonstrating a strong correlation with the Si content in the alloy.展开更多
Lightweight aluminum alloy conductor materials(Al-Mg-Si alloys)require not only high electrical conductivity to reduce electrical loss,but also high strength to withstand extreme weather conditions.To improve electric...Lightweight aluminum alloy conductor materials(Al-Mg-Si alloys)require not only high electrical conductivity to reduce electrical loss,but also high strength to withstand extreme weather conditions.To improve electrical conductivity and mechanical properties of Al-Mg-Si alloy simultaneously,the rare earth La was introduced to modify the Al-Mg-Si alloy.The effect of La addition on the microstructure,tensile properties and electrical conductivity of cast Al-Mg-Si alloy was investigated systematically.Results indicate that the appropriate La content is helpful to improve the strength and electrical conductivity of Al-Mg-Si alloys.When the addition of La is 0.2wt.%,theα-Al grains are refined apparently,Mg and Si solute atoms in the Al matrix are reduced by the formation of Mg_(2)Si phase;the distribution of Al_(11)La_(3)phases is uniform,and the morphology of AlFeSi phase transforms from continuous state to discontinuous state.The Al-Mg-Si-0.2La alloy exhibits the optimal tensile properties and electrical conductivity,with an ultimate tensile strength of 170 MPa,a yield strength of 88 MPa,an elongation of 18.9%,and an electrical conductivity of 44.0%IACS.These values represent improvements of 9.0%,15.8%,70.3%,and 17.3%,respectively,compared to the Al-Mg-Si alloy without La addition.However,excessive La deteriorates the properties of Al-Mg-Si-xLa alloys.展开更多
基金financial support from the Nuclear Energy Science&Technology and Human Resource Development Project of the Japan Atomic Energy Agency/Collaborative Laboratories for Advanced Decommissioning Science(No.R04I034)The author Ruicong Xu appreciates the scholarship(financial support)from the China Scholarship Council(CSC,No.202106380073).
文摘Laser-induced aerosols,predominantly submicron in size,pose significant environmental and health risks during the decommissioning of nuclear reactors.This study experimentally investigated the removal of laser-generated aerosol particles using a water spray system integrated with an innovative system for pre-injecting electrically charged mist in our facility.To simulate aerosol generation in reactor decommissioning,a high-power laser was used to irradiate various materials(including stainless steel,carbon steel,and concrete),generating aerosol particles that were agglomerated with injected water mist and subsequently scavenged by water spray.Experimental results demonstrate enhanced aerosol removal via aerosol-mist agglomeration,with charged mist significantly improving particle capture by increasing wettability and size.The average improvements for the stainless steel,carbon steel,and concrete were 40%,44%,and 21%,respectively.The results of experiments using charged mist with different polarities(both positive and negative)and different surface coatings reveal that the dominant polarity of aerosols varies with the irradiated materials,influenced by their crystal structure and electron emission properties.Notably,surface coatings such as ZrO_(2)and CeO_(2)were found to possibly alter aerosol charging characteristics,thereby affecting aerosol removal efficiency with charged mist configurations.The innovative aerosol-mist agglomeration approach shows promise in mitigating radiation exposure,ensuring environmental safety,and reducing contaminated water during reactor dismantling.This study contributes critical knowledge for the development of advanced aerosol management strategies for nuclear reactor decommissioning.The understanding obtained in this work is also expected to be useful for various environmental and chemical engineering applications such as gas decontamination,air purification,and pollution control.
基金supported by the Fundamental Research Funds for the Central Universities,Nos.G2021KY05107,G2021KY05101the National Natural Science Foundation of China,Nos.32071316,32211530049+1 种基金the Natural Science Foundation of Shaanxi Province,No.2022-JM482the Education and Teaching Reform Funds for the Central Universities,No.23GZ230102(all to LL and HH).
文摘Although previous studies have demonstrated that transcranial focused ultrasound stimulation protects the ischemic brain,clear criteria for the stimulation time window and intensity are lacking.Electrical impedance tomography enables real-time monitoring of changes in cerebral blood perfusion within the ischemic brain,but investigating the feasibility of using this method to assess post-stroke rehabilitation in vivo remains critical.In this study,ischemic stroke was induced in rats through middle cerebral artery occlusion surgery.Transcranial focused ultrasound stimulation was used to treat the rat model of ischemia,and electrical impedance tomography was used to measure impedance during both the acute stage of ischemia and the rehabilitation stage following the stimulation.Electrical impedance tomography results indicated that cerebral impedance increased after the onset of ischemia and decreased following transcranial focused ultrasound stimulation.Furthermore,the stimulation promoted motor function recovery,reduced cerebral infarction volume in the rat model of ischemic stroke,and induced the expression of brain-derived neurotrophic factor in the ischemic brain.Our results also revealed a significant correlation between the impedance of the ischemic brain post-intervention and improvements in behavioral scores and infarct volume.This study shows that daily administration of transcranial focused ultrasound stimulation for 20 minutes to the ischemic hemisphere 24 hours after cerebral ischemia enhanced motor recovery in a rat model of ischemia.Additionally,our findings indicate that electrical impedance tomography can serve as a valuable tool for quantitatively evaluating rehabilitation after ischemic stroke in vivo.These findings suggest the feasibility of using impedance data collected via electrical impedance tomography to clinically assess the effects of rehabilitatory interventions for patients with ischemic stroke.
基金supported by European Union Funding Programme,PNRR,No. 760058(to DMH)the UEFISCDI Project,No. PN-III-P4-IDPCE-2020-059(to APW)
文摘The major aim of stroke therapy is to stimulate brain repair and improve behavioral recovery after cerebral ischemia.One option is to stimulate endogenous neurogenesis in the subventricular zone and direct the newly formed neurons to the damaged area.However,only a small percentage of these neurons survive,and many do not reach the damaged area,possibly because the corpus callosum impedes the migration of subventricular zone-derived stem cells into the lesioned cortex.A second major obstacle to stem cell therapy is the strong inflammatory reaction induced by cerebral ischemia,whereby the associated phagocytic activity of brain macrophages removes both therapeutic cells and/or cell-based drug carriers.To address these issues,neurogenesis was electrically stimulated in the subventricular zone,followed by isolation of proliferating cells,including newly formed neurons,which were subsequently mixed with a nutritional hydrogel.This mixture was then transferred to the stroke cavity of day 14 post-stroke mice.We found that the performance of the treated animals improved in behavioral tests,including novel object,open field,hole board,grooming,and“time-to-feel”adhesive tape tests.Furthermore,immunostaining revealed that the stem cell marker nestin,the neuroepithelial marker Mash1,and the immature neuronal marker doublecortin-positive cells survived in the transplanted area for 2 weeks,possibly due to reduced phagocytic activity and supportive angiogenesis.These results clearly indicate that the transplantation of committed subventricular zone stem cells combined with a protective nutritional gel directly into the infarct cavity after the peak of stroke-induced neuroinflammation represents a feasible approach to improve neurorestoration after cerebral ischemia.
文摘提出一种改进的ELECTRE(elimination et choix traduisant la réalité)动态模糊多属性决策方法。首先,对动态决策矩阵运用熵权法获得客观的时间权重;其次,提出改进的ELECTRE方法,针对直觉模糊数不可直接比较的问题,根据隶属度、非隶属度值不同的物理含义,分别构造其级别优先的一致性和矛盾性动态指标函数,再融合为各属性的一致性和矛盾性动态指标;随后,根据其相反的赋值意义,利用时间权重分别进行集成,获得综合各时间段的一致性和矛盾性指标并进行耦合,从而得到各方案的赋值级别优先关系,最终完成方案排序。实验数据验证了方法的有效性与可行性。
基金Supported by Shanghai 2020“Science and Technology Innovation Action Plan”Medical Innovation Research Special Program:20Y21902800Shanghai Municipal Health Commission Shanghai Three-Year Action Plan to Further Accelerate the Development of Traditional Chinese Medicine Inheritance and Innovation:ZY(2021-2023)−0302)+1 种基金Shanghai Key Specialty(Acupuncture)Construction Project:shslczdzk04701Shanghai 2024"Science and Technology Innovation Action Plan"star cultivation(Sail special):24YF2740600.
文摘Transcutaneous electrical acupoint stimulation(TEAS)is a kind of physical therapy that use electric cur-rent through the electrodes placed on the surface of acupoints to produce clinical effects in the human body,which is characterized by less adverse reaction and convenient operation.It has been widely used in the treatment of various diseases.This review introduces six major clinical applications of TEAS,named analgesia,regulation of gastrointestinal function,improvement of reproductive function,enhancement of cognitive function,promotion of limb function recovery and relief of fatigue.Besides,TEAS has been ap-plied to the treatment of other chronic diseases such as hypertension and diabetes,achieving satisfactory clinical effects.However,two crucial challenges are encountered in the development of TEAS.One is the lack of standardization in the selection of parameters such as waveform,frequency,intensity and stimula-tion duration.The other is the limitation on the flexibility in the acupoint selection.This review analyzes key issues that need to be addressed in the current clinical application of TEAS,such as the selection of parameters and acupoints,and this review provides a certain reference value for optimizing regimens of TEAS and promoting its development and application.
基金supported by the Basic Science Program(No.2022R1A2C2009700)through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICTthe Basic Science Research Capacity Enhancement Project(National Research Facilities and Equipment Center)through the Korea Ba-sic Science Institute funded by the Ministry of Education(No.2019R1A6C1010047)the Industrial Strategic Technology Development Program(No.20013248)through Korea Evaluation In-stitute of Industrial Technology funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea).
文摘Thermally conductive papers with electrical insulation and mechanical robustness are essential for efficient thermal management in modern electronics.In this study,we introduced a metal ion-assisted interfacial crosslinking strategy to strengthen sugarfunctionalized graphene fluoride(SGF)and cellulose nanofibers(CNF)by hydrogen bonding and metal ion crosslinking that leads to simultaneous enhancements in thermal conductivity and mechanical properties.The facile sugarassisted ball-milling exfoliation method was developed to achieve the exfoliation of graphite fluoride and hydroxyl group functionalization on the surface of graphene fluoride.Thanks to the good dispersibility of the SGF sheets in water,the flexible SGF/CNF composite papers with hydrogen bonding were prepared via vacuum-assisted filtration.We introduced hydrogen bonding and metal ion crosslinking into SGF/CNF papers to obtain densely packed composite papers.Ca^(2+)or Al^(3+)ion-crosslinked SGF/CNF papers exhibited superior thermal and mechanical properties owing to hydrogen bonding and metal ion crosslinking.SGF/CNF-Ca^(2+)and SGF/CNF-Al^(3+)papers at 50 wt%of SGF yield in-plane thermal conductivities of 72.93 and 75.02 W m^(-1) K^(-1),and tensile strengths of 121.5 and 135.7 MPa,respectively.A thermal percolation value was observed at 12.6 vol%of SGF filler content.In addition,the SGF/CNF papers exhibited electrical insulation properties.These remarkable characteristics of the metal ion-crosslinked SGF/CNF papers are attributed to the densely packed structures caused by the strong interfacial interactions from hydrogen bonding as well as metal ion-crosslinking that could promote phonon transport.High-performance metal ion-crosslinked SGF/CNF papers with these fascinating advantages offer great potential for the thermal management of flexible electronics.
基金supported by the National Natural Science Foundation of China(No.22278260)the Open Foundation of Key Laboratory of Auxiliary Chemistry and Technology for Chemical Industry(No.KFKT2021-14)Shaanxi Collaborative Innovation Center of Industrial Auxiliary Chemistry and Technology(No.KFKT2021-14).
文摘Aramid papers (AP), made of aramid fibers, demonstrate superiority in electrical insulation applications. Unfortunately, the strength and electrical insulating properties of AP remain suboptimal, primarily due to the smooth surface and chemical inertness of aramid fibers. Herein, AP are modified via the nacre-mimetic structure composed of aramid nanofibers (ANF) and carbonylated basalt nanosheets (CBSNs). This is achieved by impregnating AP into an ANF-CBSNs (A-C) suspension containing a 3D ANF framework as the matrix and 2D CBSNs as fillers. The resultant biomimetic composite papers (AP/A-C composite papers) exhibit a layered “brick-and-mortar” structure, demonstrating superior mechanical and electrical insulating properties. Notably, the tensile strength and breakdown strength of AP/A-C5 composite papers reach 39.69 MPa and 22.04 kV mm^(−1), respectively, representing a 155 % and 85 % increase compared to those of the control AP. These impressive properties are accompanied with excellent volume resistivity, exceptional dielectric properties, impressive folding endurance, outstanding heat insulation, and remarkable flame retardance. The nacre-inspired strategy offers an effective approach for producing highly promising electrical insulating papers for advanced electrical equipment.
基金the National Natural Science Foundation of China(42472194,42302153,and 42002144)the Fundamental Research Funds for the Central Univer-sities(22CX06002A).
文摘Karst fractures serve as crucial seepage channels and storage spaces for carbonate natural gas reservoirs,and electrical image logs are vital data for visualizing and characterizing such fractures.However,the conventional approach of identifying fractures using electrical image logs predominantly relies on manual processes that are not only time-consuming but also highly subjective.In addition,the heterogeneity and strong dissolution tendency of karst carbonate reservoirs lead to complexity and variety in fracture geometry,which makes it difficult to accurately identify fractures.In this paper,the electrical image logs network(EILnet)da deep-learning-based intelligent semantic segmentation model with a selective attention mechanism and selective feature fusion moduledwas created to enable the intelligent identification and segmentation of different types of fractures through electrical logging images.Data from electrical image logs representing structural and induced fractures were first selected using the sliding window technique before image inpainting and data augmentation were implemented for these images to improve the generalizability of the model.Various image-processing tools,including the bilateral filter,Laplace operator,and Gaussian low-pass filter,were also applied to the electrical logging images to generate a multi-attribute dataset to help the model learn the semantic features of the fractures.The results demonstrated that the EILnet model outperforms mainstream deep-learning semantic segmentation models,such as Fully Convolutional Networks(FCN-8s),U-Net,and SegNet,for both the single-channel dataset and the multi-attribute dataset.The EILnet provided significant advantages for the single-channel dataset,and its mean intersection over union(MIoU)and pixel accuracy(PA)were 81.32%and 89.37%,respectively.In the case of the multi-attribute dataset,the identification capability of all models improved to varying degrees,with the EILnet achieving the highest MIoU and PA of 83.43%and 91.11%,respectively.Further,applying the EILnet model to various blind wells demonstrated its ability to provide reliable fracture identification,thereby indicating its promising potential applications.
基金supported by the Fundamental Research Funds for the Central Universities(Nos.2232023D-01 and 2232023D-07)the Shanghai Science&Technology Committee(No.22ZR1403300)the National Natural Science Foundation of China(No.52372040).
文摘Metal-organic frameworks(MOFs)have attracted significant interest as self-templates and precursors for the synthesis of carbon-based composites aimed at electromagnetic wave(EMW)absorption.However,the utilization of high-temperature treatments has introduced uncertainties regarding the compositions and microstructures of resulting derivatives.Additionally,complete carbonization has led to diminished yields of the produced carbon composites,significantly limiting their practical applications.Consequently,the exploration of pristine MOF-based EMW absorbers presents an intriguing yet challenging endeavor,primarily due to inherently low electrical conductivity.In this study,we showcase the utilization of structurally robust Zr-MOFs as scaffolds to build highly conductive Zr-MOF/PPy composites via an inner-outer dual-modification approach,which involves the production of conducting polypyrrole(PPy)both within the confined nanoporous channels and the external surface of Zr-MOFs via post-synthetic modification.The interconnection of confined PPy and surface-lined PPy together leads to a consecutive and extensive conducting network to the maximum extent.This therefore entails outstanding conductivity up to~14.3 S cm^(-1) in Zr-MOF/PPy composites,which is approximately 1-2 orders of magnitude higher than that for conductive MOF nanocomposites constructed from either inner or outer modification.Benefiting from the strong and tunable conduction loss,as well as the induced dielectric polarization originated from the porous structures and MOF-polymer interfaces,Zr-MOF/PPy exhibits excellent microwave attenuation capabilities and a tunable absorption frequency range.Specifically,with only 15 wt.%loading,the minimum reflection loss(RLmin)can reach up to-67.4 dB,accompanied by an effective absorption bandwidth(EAB)extending to 6.74 GHz.Furthermore,the microwave absorption characteristics can be tailored from the C-band to the Ku-band by adjusting the loading of PPy.This work provides valuable insights into the fabrication of conductive MOF composites by presenting a straightforward pathway to enhance and reg-ulate electrical conduction in MOF-based nanocomposites,thus paving a way to facilely fabricate pristine MOF-based microwave absorbers.
基金Supported by Zhejiang Province Traditional Chinese Medicine Science and Technology Plan Project,No.2023ZL230。
文摘BACKGROUND Although gastroscopy is a commonly used diagnostic and therapeutic technique,postoperative gastrointestinal dysfunction is prone to occur.Traditional Chinese medicine theory suggests that postoperative gastrointestinal disorders are related to spleen and stomach weakness.This study hypothesizes that the combination of acupoint application at the Ziwu Liuzhu acupoint and percutaneous acupoint electrical stimulation can promote postoperative gastrointestinal function recovery and alleviate stress reactions.AIM To investigate the effects of acupoint application of Ziwu Liuzhu combined with percutaneous acupoint electrical stimulation on postoperative gastrointestinal function recovery and stress response in patients undergoing gastrointestinal endoscopy surgery.METHODS A total of 120 patients who underwent gastroscopy surgery were selected and treated between October 2024 and January 2025.This study used a stratified block randomization method,and then allocated groups using computer-generated random number sequences(SAS 9.4 software).The groups were divided into two groups:A control group of 60 patients who received routine postoperative intervention measures,and an observation group of 60 patients who received acupuncture point application combined with transcutaneous acupoint electrical CONCLUSION The combination of percutaneous acupoint electrical stimulation in gastroscopy patients has been demonstrated to be both highly safe and effective.The benefits of this approach include the promotion of postoperative gastrointestinal function,the reduction of stress response,the attainment of optimal results,and the enhancement of patient satisfaction.
基金supported partially by grants from the National Natural Science Foundation of China(82470068,82270086,GS Zhang82372185,BP Tian)+2 种基金the Natural Science Foundation of Zhejiang Province(Key Project)(LZ25H150001,GS Zhang)the National Health Commission Scientifi c Research Fund Zhejiang Provincial Health Major Science and Technology Plan Project(co-construction project of National Health Commission Committee and Zhejiang Province)(WKJ-ZJ-2526,GS Zhang)the Medical and Health Research Program of Zhejiang Province(2023572679).
文摘Electrical impedance tomography(EIT)is a non-invasive imaging modality that generates real-time images by measuring tissue bioimpedance.It works by applying current and collecting voltage data to reconstruct images of electrical conductivity,refl ecting tissue properties.[1]We aim to off er a comprehensive guide to the fundamental technology behind EIT and to explore its clinical applications across both pulmonary and extrapulmonary domains.
基金supported by the Natural Science Foundation of Jiangsu Province(Grant No.BK20240123)the National Key Research and Development Program of China(Grant No.2022YFA1405900)the National Natural Science Foundation of China(Grant Nos.12274397,12274401,and 12034018)。
文摘The excellent mechanical properties make graphene promising for realizing nanomechanical resonators with high resonant frequencies,large quality factors,strong nonlinearities,and the capability to efectively interface with various physical systems.Equipped with gate electrodes,it has been demonstrated that these exceptional device properties can be electrically manipulated,leading to a variety of nanomechanical/acoustic applications.Here,we review the recent progress of graphene nanomechanical resonators with a focus on their electrical tunability.First,we provide an overview of diferent graphene nanomechanical resonators,including their device structures,fabrication methods,and measurement setups.Then,the key mechanical properties of these devices,for example,resonant frequencies,nonlinearities,dissipations,and mode coupling mechanisms,are discussed,with their behaviors upon electrical gating being highlighted.After that,various potential classical/quantum applications based on these graphene nanomechanical resonators are reviewed.Finally,we briefy discuss challenges and opportunities in this feld to ofer future prospects for the ongoing studies on graphene nanomechanical resonators.
基金Applied Basic Research Program of Liaoning Province(CN)(2022JH2/101300078)。
文摘Self-designed Al8Si0.4Mg0.4Fe aluminium alloy was modified with Sr,followed by solid solution and aging treatments to regulate its microstructure and mechanical/electrical properties.The results show that after the modification treatment,the room-temperature tensile strength of the alloy remains nearly unchanged,the elongation at break slightly increases from 1.82%to 3.34%,and the electrical conductivity significantly increases from 40.1%international annealed copper standard(IACS)to 42.0%IACS.After the modification,the alloy was subjected to solid solution treatment at 515℃for 8 h,followed by aging treatment at 180,200,220 and 240℃for 6 h.With increasing aging temperature,the electrical conductivity increases monotonously from 41.4%IACS to 45.5%IACS,while the room-temperature tensile strength initially increases and then decreases.At 200℃,the alloy achieves an optimal balance between electrical conductivity and room-temperature tensile strength:the electrical conductivity is 42.5%IACS,and the room-temperature tensile strength is 282.9 MPa.When the aging temperature continues to rise,the alloy undergoes overaging.Although the conductivity continues to increase,the room-temperature tensile strength drops sharply,and it is only 177.1 MPa at 240℃.
基金support provided by the National Natural Science Foundation of China(Nos.52405364,and 52171110)the Jiangsu Funding Program for Excellent Postdoctoral Talent.W.Huo acknowledges the support from the European Union Horizon 2020 Research and Innovation Program(No.857470)+1 种基金from the European Regional Development Fund via the Foundation for Polish Science International Research Agenda PLUS Program(No.MAB PLUS/2018/8)The publication was partly created within the framework of the project of the Minister of Science and Higher Education"Support for the activities of Centers of Excellence established in Poland under Horizon 2020"(No.MEiN/2023/DIR/3795).
文摘The effects of drawing strain during intermediate annealing on the microstructure and properties of Cu-20 wt%Fe alloy wires while maintaining constant total deformation were investigated.Intermediate annealing effectively removes work hardening in both the Cu matrix and Fe fibers,restoring their plastic deformation capacity and preserving fiber continuity during subsequent redrawing.The process also refines the Fe phase,leading to a more uniform size distribution and straighter,better-aligned Cu/Fe phase interfaces,thereby enhancing the comprehensive properties of the alloy.The magnitude of drawing strain during intermediate annealing plays a critical role in balancing the mechanical strength and electrical conductivity of redrawn wires.A lower initial drawing strain requires greater redrawing strain,leading to excessive hardening of the Fe fibers,which negatively impacts the electrical conductivity and tensile plasticity.Conversely,a higher initial drawing strain can result in insufficient work hardening during the redrawing deformation process,yielding minimal strength improvements.Among the tested alloys,H/3.5 wires show a slight reduction in strength and hardness compared to W and H/4.5 wires but exhibit a significant increase in tensile elongation and electrical conductivity.The tensile strength was 755 MPa,and the electrical conductivity was 47%international-annealed copper standard(IACS).The optimal performance is attributed to the formation of a high-density,ultrafine Fe fiber structure-aligned parallel to the drawing direction,which is achieved through a suitable combination of the drawing process and intermediate annealing.
基金supported in part by the National Natural Science Foundation of China under Grant 52277139 and 52367014in part by the Guangxi Science Fund for Distinguished Young Scholars under Grant 2024GXNSFFA999017.
文摘Fluorination is a critical surface modification technique for enhancing the electrical performance of composite insulators.This study employs molecular simulations to examine the microstructure and space charge behavior of fluorinated and non-fluorinated silicone rubber under an electric field,with experimental validation.The results show that fluorinated silicone rubber exhibits lower total energy,higher polarization,and stronger dipole moments compared to its non-fluorinated counterpart,shifting the material from an insulating to a conductive state.Under lower electric field strengths,the carbon-silicon bonds in fluorinated silicone rubber are longer,but it maintains geometric stability under higher fields.The energy gap changes across different fluorination modes and varies with electric field strength,indicating that fluorination affects conductivity differently at various field intensities.Both fluorination methods improve conductivity in the 0–3.8 V/nm range,with substitutional fluorination showing superior performance between 3.8 and 8.9 V/nm.Above 9.1 V/nm,fluorination maximizes conductivity.The fluorinated samples exhibit a greater redshift at higher electric fields,resulting in enhanced conductivity and improved surface charge distribution.These findings offer insights into the microscopic effects of fluorination on silicone rubber’s electrical properties,while experiments confirm that fluorination increases hydrophobicity and boosts DC flashover voltage,further enhancing the material’s performance.
文摘The integrated innovation of artificial intelligence and electrical automation technology not only represents a further innovation of traditional models but also promotes the innovative development of both artificial intelligence and electrical automation technology.This paper delves into the significance of the integrated innovative applications of artificial intelligence and electrical automation technology,as well as the strategies for such applications,aiming to better achieve the intelligent development of electrical automation technology.
基金supported by the National Natural Science Foundation of China(52225101)the Jinhua Science and Technology Program of China(2024A221787)+1 种基金the Sichuan Science and Technology Program of China(2025ZNSFSC0388)the Chongqing Special Project for Science and Technology Innovation of China(CSTB2023YSZX-JCX0006).
文摘Magnesium(Mg)alloys offer significant potential for conductive applications,thanks to their distinctive attributes,including high specific strength,excellent electrical conductivity(EC),low density,electromagnetic interference shielding effectiveness(EMI SE),and recyclability.However,a major challenge in Mg alloy research is balancing high strength with good EC,as strengthening these alloys often compromises their EC.This paper offers an in-depth analysis of the mechanisms,strategies,and applications aimed at improving the EC of Mg alloys.A bibliometric study is performed to uncover the main research trends and emerging hotspots within the field.The review then examines various strategies to improve EC focusing on factors such as solute elements,second phases,grain boundaries,textures,and vacancies.By carefully controlling alloy composition and optimizing heat treatment processes,significant advancements have been achieved by researchers in developing Mg alloys that possess both high strength and high EC,especially in Mg-Al,Mg-Zn,Mg-RE alloy systems and composites.Finally,the paper outlines future research directions,stressing the importance of further exploration into alloying element selection,heat treatment optimization,and other advanced strategies.These efforts are crucial for overcoming current challenges and expanding the application of Mg alloys in EC fields.
基金National Key Research and Development Program of China(2021YFA1501302)the National Natural Science Foundation of China(22121004,22122808)+1 种基金the Haihe Laboratory of Sustainable Chemical Transformations and the Program of Introducing Talents of Discipline to Universities(BP0618007)for financial supportsupported by the XPLORER PRIZE.
文摘Noise is inevitable in electrical capacitance tomography(ECT)measurements.This paper describes the influence of noise on ECT performance for measuring gas-solids fluidized bed characteristics.The noise distribution is approximated by the Gaussian distribution and added to experimental capacitance data with various intensities.The equivalent signal strength(Ф)that equals the signal-to-noise ratio of packed beds is used to evaluate noise levels.Results show that the Pearson correlation coefficient,which indicates the similarity of solids fraction distributions over pixels,increases with Ф,and reconstructed images are more deteriorated at lower Ф.Nevertheless,relative errors for average solids fraction and bubble size in each frame are less sensitive to noise,attributed to noise compromise caused by the process of pixel values.These findings provide useful guidance for assessing the accuracy of ECT measurements of multiphase flows.
基金financially supported by the Nanjing Chervon Auto Precision Technology Co.,Ltd.(Grant No.322040)。
文摘In this study,Al-xSi-0.3Mn-0.3Mg-0.14Fe alloys(x=6.5,7.5,8.5,wt.%)were prepared by super-slow-speed die-casting,and the effects of Si content on the microstructure,mechanical,and thermal/electrical conductivities in as-cast,T5,and T6 states(DIN EN 1706:2020)were investigated.It is found that the increase of Si content in the alloy enhances the formation of eutectic segregation band in the casting surface microstructure.Within the Si content range of 6.5%-8.5%,as a comprehensive evaluation criterion of mechanical properties,the quality index(QI)of 376.1 MPa can be obtained in the as-cast state of the alloy with about 7.5%Si content,373.4 MPa in T5 state of the alloy with 6.5%Si content,and 432.2 MPa in T6 state of the alloy containing 8.5%Si.The heat treatment state significantly affects the thermal conductivity and electrical conductivity of the alloys.The eutectic silicon in the alloy is segemented and further spheroidizaed during the solution process,and the solute atoms of Mg and Si are more adequately precipitated during the aging process.Both of these greatly reduce the probability of electron scattering.Thus,T6 treatment significantly improves the electrical and thermal conductivities.With the increase of Si content,both thermal conductivity and electrical conductivity decrease slightly,demonstrating a strong correlation with the Si content in the alloy.
基金supported by the National Natural Science Foundation of China(No.51704087)the Natural Science Foundation of Heilongjiang Province(No.LH2020E083).
文摘Lightweight aluminum alloy conductor materials(Al-Mg-Si alloys)require not only high electrical conductivity to reduce electrical loss,but also high strength to withstand extreme weather conditions.To improve electrical conductivity and mechanical properties of Al-Mg-Si alloy simultaneously,the rare earth La was introduced to modify the Al-Mg-Si alloy.The effect of La addition on the microstructure,tensile properties and electrical conductivity of cast Al-Mg-Si alloy was investigated systematically.Results indicate that the appropriate La content is helpful to improve the strength and electrical conductivity of Al-Mg-Si alloys.When the addition of La is 0.2wt.%,theα-Al grains are refined apparently,Mg and Si solute atoms in the Al matrix are reduced by the formation of Mg_(2)Si phase;the distribution of Al_(11)La_(3)phases is uniform,and the morphology of AlFeSi phase transforms from continuous state to discontinuous state.The Al-Mg-Si-0.2La alloy exhibits the optimal tensile properties and electrical conductivity,with an ultimate tensile strength of 170 MPa,a yield strength of 88 MPa,an elongation of 18.9%,and an electrical conductivity of 44.0%IACS.These values represent improvements of 9.0%,15.8%,70.3%,and 17.3%,respectively,compared to the Al-Mg-Si alloy without La addition.However,excessive La deteriorates the properties of Al-Mg-Si-xLa alloys.
