The replacement metal gate（RMG） defectivity performance control is very challenging in high-k metal gate（HKMG） chemical mechanical polishing（CMP）. In this study, three major defect types, including fall-on parti...The replacement metal gate（RMG） defectivity performance control is very challenging in high-k metal gate（HKMG） chemical mechanical polishing（CMP）. In this study, three major defect types, including fall-on particles, micro-scratch and corrosion have been investigated. The research studied the effects of polishing pad,pressure, rotating speed, flow rate and post-CMP cleaning on the three kinds of defect, which finally eliminated the defects and achieved good surface morphology. This study will provide an important reference value for the future research of aluminum metal gate CMP.展开更多
T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection met...T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection methods face challenges owing to surface oxide scales,and conventional high-precision magnetic sensors are ineffective at high temperatures.To overcome these limitations,a small coil sensor was employed to measure the residual magnetism strength in oscillation traces,using metal magnetic memory and electromagnetic induction methods,which can carry out detection without an external excitation source.Using this technology,the proposed scheme successfully detects defects at high tempe-ratures(up to 670℃)without a cooling device.The key findings include the ability to detect both surface and near-surface defects,such as cracks and oscillation marks,with an enhanced signal-to-noise ratio(SNR)of 7.2 dB after signal processing.The method’s practicality was validated in a steel mill environment,where testing on casting slabs effectively detected defects,providing a foundation for improving industrial quality control.The proposed detection scheme offers a significant advancement in nondestructive testing(NDT)for high-temperature applications,contributing to more efficient and accurate monitoring of ferromagnetic material integrity.展开更多
Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellen...Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellent catalytic activity,a remarkable adsorption capacity,and different interfacial physicochemical functionalities.Surface-modified biochars have found wide applications in energy storage,environmental remediation,and catalysis.However,achieving precise and controllable modification of their active sites remains a challenge.Recent advances and future prospects for controlling their surface morphology,defect engineering,and surface coating strategies,with particular attention to their means of fabrication,are reviewed.展开更多
Background:Rats are often used to prepare skin defect models.However,the skin defect sizes of the models prepared by researchers are different,and the lack of consensus on the critical-size defect makes it difficult t...Background:Rats are often used to prepare skin defect models.However,the skin defect sizes of the models prepared by researchers are different,and the lack of consensus on the critical-size defect makes it difficult to compare their research results.Methods:The time for wound closure was evaluated and recorded through gross observation.The regression equation between the healing time and the diameter of skin defect was established,which can be used to predict the healing time for a certain skin defect size in rats.Histochemical and immunohistochemical staining was used to observe the regeneration and reconstruction of skin appendages,and the functional skin repair was quantitatively scored.Results:The critical-size defect of rats was determined based on the maximum capacity of structural skin repair,and the functional skin repair was quantitatively scored based on the regeneration and reconstruction of skin appendages.The allowable range of critical-size skin defect of SD rats lies between 45 and 50 mm in diameter.The concept of structural repair and the category of functional repair of injured skin are put forward.The regression equation between the structural skin healing time and defect diameters is established.Conclusion:The allowable range of skin critical-size defect of SD rats lies between 45 and 50 mm in diameter.The regression equation between the structural skin healing time and defect diameters can be used to predict the healing time for a certain skin defect size in rats.展开更多
Among various advanced oxidation processes(AOPs),heterogeneous catalytic ozonation has garnered extensive attention in wastewater treatment owing to its broad pH range applicability and the elimination of the need for...Among various advanced oxidation processes(AOPs),heterogeneous catalytic ozonation has garnered extensive attention in wastewater treatment owing to its broad pH range applicability and the elimination of the need for additional energy input.Enhancing catalyst activity by introducing oxygen vacancies has been used extensively in heterogeneous catalytic ozonation.This paper reviews prevalent methods for the construction and characterization of oxygen vacancies.Based on a thorough examination of existing research,the role of oxygen vacancies is categorized according to their primary mechanisms of action in heterogeneous catalytic ozonation.For example,modulation of the catalyst electronic structure to enhance electron transfer;participation in the reaction as an active site to generate radicals and non-radicals;and exposure of more metal sites to enhance the reaction.Lastly,the paper delineates the limitations and future research directions concerning the role of oxygen vacancies in catalytic ozonation.This review addresses the gap in existing literature concerning the role of oxygen vacancies in catalytic ozone systems,establishes a comprehensive theoretical framework to aid in the design of efficient ozone catalysts,and delves into the functionality of oxygen vacancies in heterogeneous catalytic ozone reactions.展开更多
Manual inspection of onba earing casting defects is not realistic and unreliable,particularly in the case of some micro-level anomalies which lead to major defects on a large scale.To address these challenges,we propo...Manual inspection of onba earing casting defects is not realistic and unreliable,particularly in the case of some micro-level anomalies which lead to major defects on a large scale.To address these challenges,we propose BearFusionNet,an attention-based deep learning architecture with multi-stream,which merges both DenseNet201 and MobileNetV2 for feature extraction with a classification head inspired by VGG19.This hybrid design,figuratively beaming from one layer to another,extracts the enormity of representations on different scales,backed by a prepreprocessing pipeline that brings defect saliency to the fore through contrast adjustment,denoising,and edge detection.The use of multi-head self-attention enhances feature fusion,enabling the model to capture both large and small spatial features.BearFusionNet achieves an accuracy of 99.66%and Cohen’s kappa score of 0.9929 in Kaggle’s Real-life Industrial Casting Defects dataset.Both McNemar’s and Wilcoxon signed-rank statistical tests,as well as fivefold cross-validation,are employed to assess the robustness of our proposed model.To interpret the model,we adopt Grad-Cam visualizations,which are the state of the art standard.Furthermore,we deploy BearFusionNet as a webbased system for near real-time inference(5-6 s per prediction),which enables the quickest yet accurate detection with visual explanations.Overall,BearFusionNet is an interpretable,accurate,and deployable solution that can automatically detect casting defects,leading to significant advances in the innovative industrial environment.展开更多
The interdependence of electrical parameters has long inhibited the progress of bismuth telluride(Bi_(2)Te3),limiting its widespread application in thermoelectric cooling and power generation.This work investigates th...The interdependence of electrical parameters has long inhibited the progress of bismuth telluride(Bi_(2)Te3),limiting its widespread application in thermoelectric cooling and power generation.This work investigates the n-type Bi_(2)Te_(2.79)Se_(0.21)I_(0.004)(Bi_(2)(Te,Se)_(3),BTS)system with light Zn doping,revealing that Zn addition simultaneously enhances the Seebeck coefficient(S)and electrical conductivity(σ)through the modulation of defect composition and multi-level band regulation.The substitution of Zn atoms at Bi sites enhances S via bandgap(E_(g))widening,band flattening,and band splitting effects,contributing to a competitive power factor(PF)of∼60μW⋅cm^(−1)⋅K^(−2).Additionally,thermal conductivity is maintained at a low level,leading to an extraordinary figure-of-merit(ZT)value of∼1.3 at room temperature.Furthermore,the Bi_(2)Zn_(0.01)Te_(2.79)Se_(0.21)I_(0.004) system demonstrates impressive thermoelectric device performance,with a maximum cooling temperature difference(ΔT_(max))of∼70.0 K at 300 K,rising to∼78.0 K at 323 K and∼85.7 K at 343 K,as well as a maximum conversion efficiency(η_(max))of∼6.2%under aΔT of 200 K.This study clarifies the mechanism of Zn doping and presents a cost-effective strategy for enhancing the performance of n-type BTS thermoelectrics and their devices.展开更多
Density functional theory(DFT)calculations were employed to investigate the adsorption behavior of NH_(3),AsH_(3),PH_(3),CO_(2),and CH_(4)molecules on both pristine and mono-vacancy phosphorene sheets.The pristine pho...Density functional theory(DFT)calculations were employed to investigate the adsorption behavior of NH_(3),AsH_(3),PH_(3),CO_(2),and CH_(4)molecules on both pristine and mono-vacancy phosphorene sheets.The pristine phosphorene surface showsweak physisorption with all the gasmolecules,inducing onlyminor changes in its structural and electronic properties.However,the introduction ofmono-vacancies significantly enhances the interaction strength with NH_(3),PH_(3),CO_(2),and CH_(4).These variations are attributed to substantial charge redistribution and orbital hybridization in the presence of defects.The defective phosphorene sheet also exhibits enhanced adsorption energies,along with favorable sensitivity and recovery characteristics,highlighting its potential as a promising gas sensor for NH_(3),AsH_(3),PH_(3),CO_(2),and CH_(4)at ambient conditions.展开更多
The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the orig...The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the originally assigned pages(2595-2614),we will need to publish an erratum to correct the article and restore the original page range.The original article has been corrected.展开更多
Algal blooms in eutrophic water often produce microcystins,which can lead to multi-organ dysfunction and even mortality in many organisms.Therefore,the elimination of microcystins in water is an urgent issue that need...Algal blooms in eutrophic water often produce microcystins,which can lead to multi-organ dysfunction and even mortality in many organisms.Therefore,the elimination of microcystins in water is an urgent issue that needs to be addressed.Herein,we develop a dual defect engineering strategy to construct graphite-like carbon nitride with N vacancies and-C≡N groups(NgCN)nanosheets for microcystin-LR(MC-LR)photodegradation.According to our theoretical calculations and actual findings,the NgCN nanosheets enhanced recyclability for the removal of MC-LR while also demonstrating outstanding photocatalytic efficacy,significantly surpassing the graphite-like carbon nitride under visible light,which is ascribed to efficient charge separation as well as narrowing the bandgap.Impressively,the water quality after photodegradation has been proven to be safe based on International Organization for Standardization(ISO)standards.This finding provides meaningful insights into understanding the relationship between defect engineering and photodegradation performance to design photocatalytic materials with higher activity for environmental remediation.展开更多
The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precis...The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness.展开更多
Photocatalytic transfer hydrogenation using water as the proton source has emerged as an attractive and green approach for the catalytic reduction of unsaturated bonds.Herein,we report an oxygen-defective TiO_(2)-supp...Photocatalytic transfer hydrogenation using water as the proton source has emerged as an attractive and green approach for the catalytic reduction of unsaturated bonds.Herein,we report an oxygen-defective TiO_(2)-supported palladium catalyst(Pd-TiO_(2)-Ov)for efficient photocatalytic water-donating transfer hydrogenation of anethole towards 4-n-propylanisole in a high yield of 99.9%,which is significantly higher compared to the pristine TiO_(2)-supported palladium catalyst(Pd-TiO_(2),74%).The enhanced performance is ascribed to the presence of oxygen vacancies,which facilitate light absorption and suppress the recombination of photogenerated electron-hole pairs.Furthermore,the Pd-TiO_(2)-Ov is versatile in hydrogenating various alkene substrates including those with hydroxyl,ether,fluoride,and chloride functional groups in full conversion,thus offering a green method for transfer hydrogenation of alkenes.This study provides new insights and advances in current hydrogenation technology with water as the proton source.展开更多
This comprehensive study investigates the formation and evolution of intermetallic compounds during the solidification process of magnesium alloys using advanced micro X-ray computed tomography.By analyzing both commo...This comprehensive study investigates the formation and evolution of intermetallic compounds during the solidification process of magnesium alloys using advanced micro X-ray computed tomography.By analyzing both common industrial Mg-Al-Zn alloys and a novel rare earth-containing Mg-Ni-Gd-Y alloy,we aim to characterize the nucleation,growth,and distribution of Al-Mn and eutectic intermetallics across various stages of solidification.The non destructive imaging technique employed in this research provides high-resolution,three-dimensional insights into the microstructural development,allowing for a detailed examination of the morphology,spatial arrangement,and interconnectivity of intermetallic phases.This approach overcomes limitations of traditional two-dimensional metallographic methods,offering a more comprehensive understanding of the complex three-dimensional structures formed during solidification.展开更多
The transition of perovskite solar cells(PSCs)from laboratory-scale devices to large-area commercial modules is fundamentally challenged by the poor uniformity and repeatability of conventional solution-based surface ...The transition of perovskite solar cells(PSCs)from laboratory-scale devices to large-area commercial modules is fundamentally challenged by the poor uniformity and repeatability of conventional solution-based surface passivation.To overcome this critical bottleneck,we introduce a vacuumevaporated passivation strategy using the thermally evaporable molecule bathophenanthroline(BPhen).This solvent-free approach yields highly uniform passivation layers,effectively suppressing surface defects and enhancing charge extraction through synergistic π-π stacking with the C60 electron transport layer.Our fully vacuum-evaporated PSCs achieve a remarkable power conversion efficiency(PCE)of 20.13%for champion cells and 18.42%for 5 cm×5 cm mini-modules.These results not only demonstrate the superiority of evaporated passivation for fabricating large-area devices but also establish a scalable and robust engineering pathway toward the commercial production of highperformance perovskite photovoltaics.展开更多
Proton-conducting oxides constitute a wide class of materials that exhibit pronounced proton transport in humid atmospheres.Owing to their high proton mobility,these oxides are regarded as promising electrolytes for l...Proton-conducting oxides constitute a wide class of materials that exhibit pronounced proton transport in humid atmospheres.Owing to their high proton mobility,these oxides are regarded as promising electrolytes for low-and intermediate-temperature protonic ceramic fuel cells and electrolysis cells,which offer efficient and clean energy conversion.Protons appear in complex oxides through a dissociative water adsorption process,which consists of the interaction between existing oxygen vacancies and water molecules in the gas phase.This process is also known as hydration or water uptake.Within the present work,we analyze the hydration features of BaSn_(1-x)In_(x)O_(3-δ)perovskite materials(BSIx),which include a wide range of solid solutions(0≤x<0.7)and a nearly theoretical hydration limit for almost all studied compounds at the same time.The latter is a unique property of In-doped stannates,which is untypical for most other proton-conducting oxides.Along with the experimental data on the water uptake of BSIx,we provide an in-depth investigation of proton concentrations depending on external factors,involving a further comparison with literature data on materials hydration,as well as the discovery of hidden relationships between proton concentration and various functional properties.Therefore,this work contributes to theoretical and applied investigations of proton-conducting oxides,especially in the context of their hydration behavior.展开更多
Although the certified power conversion efficiency(PCE)of single-junction perovskite solar cells(PSCs)has achieved a high level of 27%,approaching the single-crystalline silicon solar cells,the device stability remain...Although the certified power conversion efficiency(PCE)of single-junction perovskite solar cells(PSCs)has achieved a high level of 27%,approaching the single-crystalline silicon solar cells,the device stability remains an urgent issue to be resolved for the commercialization.Defect passivation emerged as a viable approach to enhance the operational stability of the solar devices.Herein,phenylthiourea(PhTu)derivatives are selected as effective passivation agents to enhance the optoelectronic properties of printed methylammonium lead iodide(MAPbI_(3))films.It is demonstrated that incorporating a small amount of 1-(4-carboxyphenyl)-2-thiourea(PhTu-COOH)significantly reduces the trap-state density and leads to longer carrier lifetime of the perovskite films.As a result,the inverted solar device made of Ph Tu-COOH-modified MAPbI_(3) perovskite film shows remarkably improved efficiency(from 17.29%to 20.22%)and obviously increased open-circuit voltage(V_(OC))(from 1.043 to 1.143 V),as compared with the pristine device.Moreover,the Ph Tu-COOH-modified PSCs exhibit enhanced operational stability due to the significantly reduced trap-state density.Finally,the optimized solar module fabricated with an active area of 11.28 cm^(2) delivers a high PCE of 17.07%with negligible V_(OC)loss,demonstrating the feasibility of the blade-coating method for large-area perovskite film deposition.展开更多
A parametric study was performed to explore the effect of runner thickness,filtration,and hydrogen content on the mechanical properties and defect formation in Al-7%Si-0.3%Mg(2L99)sand castings.A two-level full factor...A parametric study was performed to explore the effect of runner thickness,filtration,and hydrogen content on the mechanical properties and defect formation in Al-7%Si-0.3%Mg(2L99)sand castings.A two-level full factorial design of experiments was used to statistically evaluate these parameters and the tensile properties were characterized via Weibull distribution analysis.The findings reveal that decreasing the runner thickness from25 mm to 10 mm and using 10 PPI ceramic filters improve mechanical properties by minimizing double oxide film entrainment as confirmed by electron microscopy examination.In addition,lowering hydrogen concentrations within the Al alloy from 0.24 cm^(3)/100 g Al to 0.12 cm^(3)/100 g Al is also shown to enhance casting integrity by suppressing bifilm inflation and subsequent pore formation.ANOVA results indicate that the hydrogen content is the most important factor,contributing 53%to the variability in mechanical properties,followed by filtration(25%)and runner thickness(17%).The optimized casting conditions including thin runners(10 mm thick),melt filtration,and a low hydrogen level(0.12 cm^(3)/100 g Al),result in an approximately 474%increase in the shape factor and a 107%increase in the characteristic life of UTS,as well as an approximately 413%increase in the shape factor and a 149%increase in characteristic life of elongation.The outcomes suggest that controlled filling systems and melt treatment are critical for producing consistent,high integrity aluminum castings in industrial applications.展开更多
Metal-organic framework(MOF)-derived porous carbon has attracted particular attention in the electrochemical energy storage field,of which the key is the design and preparation of electrode materials with adjustable p...Metal-organic framework(MOF)-derived porous carbon has attracted particular attention in the electrochemical energy storage field,of which the key is the design and preparation of electrode materials with adjustable porosity and defects for supercapacitors.Here,a novel strategy of coating ZIF-8 with coal tar pitch(CTP)is presented to tailor the porosity and defects of derived porous carbon,by which the inward contraction of ZIF-8 is prevented to enlarge the ultra-micropores,and the defects of ZIF-8-derived carbon are repaired to form a continuous conjugated network.The tradeoff between porosity and electrical conductivity endows this novel hard/soft carbon electrode with fast ion/electron diffusion,achieving high yet balanced capacitance and rate performance of a top-level specific area-normalized capacitance(40μF cm^(-2))and a capacitance retention of 52.1%at a 1000-fold increased current density.Meanwhile,the novel electrode realizes a high capacitance of 704 F g^(-1)at 1 A g^(-1)and capacitance retention of 91.9%after 50000 cycles in KOH+PPD electrolyte.This study provides an effective approach to designing novel hard/soft carbon with tuned porosity and carbon defects from MOFs and CTP for supercapacitors and other metal-ion batteries.展开更多
Fabric defect detection plays a vital role in ensuring textile quality.However,traditional manual inspection methods are often inefficient and inaccurate.To overcome these limitations,we propose FD-YOLO,an enhanced li...Fabric defect detection plays a vital role in ensuring textile quality.However,traditional manual inspection methods are often inefficient and inaccurate.To overcome these limitations,we propose FD-YOLO,an enhanced lightweight detection model based on the YOLOv11n framework.The proposed model introduces the Bi-level Routing Attention(BRAttention)mechanism to enhance defect feature extraction,enabling more detailed feature representation.It proposes Deep Progressive Cross-Scale Fusion Neck(DPCSFNeck)to better capture smallscale defects and incorporates a Multi-Scale Dilated Residual(MSDR)module to strengthen multi-scale feature representation.Furthermore,a Shared Detail-Enhanced Lightweight Head(SDELHead)is employed to reduce the risk of gradient explosion during training.Experimental results demonstrate that FD-YOLO achieves superior detection accuracy and Lightweight performance compared to the baseline YOLOv11n.展开更多
The reliable operation of power grid secondary equipment is an important guarantee for the safety and stability of the power system.However,various defects could be produced in the secondary equipment during longtermo...The reliable operation of power grid secondary equipment is an important guarantee for the safety and stability of the power system.However,various defects could be produced in the secondary equipment during longtermoperation.The complex relationship between the defect phenomenon andmulti-layer causes and the probabilistic influence of secondary equipment cannot be described through knowledge extraction and fusion technology by existing methods,which limits the real-time and accuracy of defect identification.Therefore,a defect recognition method based on the Bayesian network and knowledge graph fusion is proposed.The defect data of secondary equipment is transformed into the structured knowledge graph through knowledge extraction and fusion technology.The knowledge graph of power grid secondary equipment is mapped to the Bayesian network framework,combined with historical defect data,and introduced Noisy-OR nodes.The prior and conditional probabilities of the Bayesian network are then reasonably assigned to build a model that reflects the probability dependence between defect phenomena and potential causes in power grid secondary equipment.Defect identification of power grid secondary equipment is achieved by defect subgraph search based on the knowledge graph,and defect inference based on the Bayesian network.Practical application cases prove this method’s effectiveness in identifying secondary equipment defect causes,improving identification accuracy and efficiency.展开更多
基金Project supported by the Major National Science and Technology Special Projects(No.2009ZX02308)the Natural Science Foundation for the Youth of Hebei Province(Nos.F2012202094,F2015202267)the Outstanding Youth Science and Technology Innovation Fund of Hebei University of Technology(No.2013010)
文摘The replacement metal gate（RMG） defectivity performance control is very challenging in high-k metal gate（HKMG） chemical mechanical polishing（CMP）. In this study, three major defect types, including fall-on particles, micro-scratch and corrosion have been investigated. The research studied the effects of polishing pad,pressure, rotating speed, flow rate and post-CMP cleaning on the three kinds of defect, which finally eliminated the defects and achieved good surface morphology. This study will provide an important reference value for the future research of aluminum metal gate CMP.
文摘T he residual stray magnetic fields present in ferromagnetic casting slabs were investigated in this work,which result from the magnetic fields generated during the steel casting process.Existing optical detection methods face challenges owing to surface oxide scales,and conventional high-precision magnetic sensors are ineffective at high temperatures.To overcome these limitations,a small coil sensor was employed to measure the residual magnetism strength in oscillation traces,using metal magnetic memory and electromagnetic induction methods,which can carry out detection without an external excitation source.Using this technology,the proposed scheme successfully detects defects at high tempe-ratures(up to 670℃)without a cooling device.The key findings include the ability to detect both surface and near-surface defects,such as cracks and oscillation marks,with an enhanced signal-to-noise ratio(SNR)of 7.2 dB after signal processing.The method’s practicality was validated in a steel mill environment,where testing on casting slabs effectively detected defects,providing a foundation for improving industrial quality control.The proposed detection scheme offers a significant advancement in nondestructive testing(NDT)for high-temperature applications,contributing to more efficient and accurate monitoring of ferromagnetic material integrity.
文摘Biomass-derived carbon materials are favored for their abundance and sustainability,and ease of preparation and modification.By surface activation and modification they can have a good electrical conductivity,excellent catalytic activity,a remarkable adsorption capacity,and different interfacial physicochemical functionalities.Surface-modified biochars have found wide applications in energy storage,environmental remediation,and catalysis.However,achieving precise and controllable modification of their active sites remains a challenge.Recent advances and future prospects for controlling their surface morphology,defect engineering,and surface coating strategies,with particular attention to their means of fabrication,are reviewed.
基金National Key Research and Development Program of China,Grant/Award Number:2023YFC2410403。
文摘Background:Rats are often used to prepare skin defect models.However,the skin defect sizes of the models prepared by researchers are different,and the lack of consensus on the critical-size defect makes it difficult to compare their research results.Methods:The time for wound closure was evaluated and recorded through gross observation.The regression equation between the healing time and the diameter of skin defect was established,which can be used to predict the healing time for a certain skin defect size in rats.Histochemical and immunohistochemical staining was used to observe the regeneration and reconstruction of skin appendages,and the functional skin repair was quantitatively scored.Results:The critical-size defect of rats was determined based on the maximum capacity of structural skin repair,and the functional skin repair was quantitatively scored based on the regeneration and reconstruction of skin appendages.The allowable range of critical-size skin defect of SD rats lies between 45 and 50 mm in diameter.The concept of structural repair and the category of functional repair of injured skin are put forward.The regression equation between the structural skin healing time and defect diameters is established.Conclusion:The allowable range of skin critical-size defect of SD rats lies between 45 and 50 mm in diameter.The regression equation between the structural skin healing time and defect diameters can be used to predict the healing time for a certain skin defect size in rats.
基金support from the Key R&D Program of Zhejiang province(No.2024C03136).
文摘Among various advanced oxidation processes(AOPs),heterogeneous catalytic ozonation has garnered extensive attention in wastewater treatment owing to its broad pH range applicability and the elimination of the need for additional energy input.Enhancing catalyst activity by introducing oxygen vacancies has been used extensively in heterogeneous catalytic ozonation.This paper reviews prevalent methods for the construction and characterization of oxygen vacancies.Based on a thorough examination of existing research,the role of oxygen vacancies is categorized according to their primary mechanisms of action in heterogeneous catalytic ozonation.For example,modulation of the catalyst electronic structure to enhance electron transfer;participation in the reaction as an active site to generate radicals and non-radicals;and exposure of more metal sites to enhance the reaction.Lastly,the paper delineates the limitations and future research directions concerning the role of oxygen vacancies in catalytic ozonation.This review addresses the gap in existing literature concerning the role of oxygen vacancies in catalytic ozone systems,establishes a comprehensive theoretical framework to aid in the design of efficient ozone catalysts,and delves into the functionality of oxygen vacancies in heterogeneous catalytic ozone reactions.
基金funded by Multimedia University,Cyberjaya,Selangor,Malaysia(Grant Number:PostDoc(MMUI/240029)).
文摘Manual inspection of onba earing casting defects is not realistic and unreliable,particularly in the case of some micro-level anomalies which lead to major defects on a large scale.To address these challenges,we propose BearFusionNet,an attention-based deep learning architecture with multi-stream,which merges both DenseNet201 and MobileNetV2 for feature extraction with a classification head inspired by VGG19.This hybrid design,figuratively beaming from one layer to another,extracts the enormity of representations on different scales,backed by a prepreprocessing pipeline that brings defect saliency to the fore through contrast adjustment,denoising,and edge detection.The use of multi-head self-attention enhances feature fusion,enabling the model to capture both large and small spatial features.BearFusionNet achieves an accuracy of 99.66%and Cohen’s kappa score of 0.9929 in Kaggle’s Real-life Industrial Casting Defects dataset.Both McNemar’s and Wilcoxon signed-rank statistical tests,as well as fivefold cross-validation,are employed to assess the robustness of our proposed model.To interpret the model,we adopt Grad-Cam visualizations,which are the state of the art standard.Furthermore,we deploy BearFusionNet as a webbased system for near real-time inference(5-6 s per prediction),which enables the quickest yet accurate detection with visual explanations.Overall,BearFusionNet is an interpretable,accurate,and deployable solution that can automatically detect casting defects,leading to significant advances in the innovative industrial environment.
基金supported by the National Key Research and Development Program of China (Grant No.2024YFA1210400)the National Science Fund for Distinguished Young Scholars (Grant No.52525101)+3 种基金the National Natural Science Foundation of China (Grant Nos.52450001 and 22409014)the International Cooperation and Exchange of the National Natural Science Foundation of China (Grant No.52411540237)the Tencent Xplorer Prizethe support of the National High-Level Talent Special Support Programs—Young Talents。
文摘The interdependence of electrical parameters has long inhibited the progress of bismuth telluride(Bi_(2)Te3),limiting its widespread application in thermoelectric cooling and power generation.This work investigates the n-type Bi_(2)Te_(2.79)Se_(0.21)I_(0.004)(Bi_(2)(Te,Se)_(3),BTS)system with light Zn doping,revealing that Zn addition simultaneously enhances the Seebeck coefficient(S)and electrical conductivity(σ)through the modulation of defect composition and multi-level band regulation.The substitution of Zn atoms at Bi sites enhances S via bandgap(E_(g))widening,band flattening,and band splitting effects,contributing to a competitive power factor(PF)of∼60μW⋅cm^(−1)⋅K^(−2).Additionally,thermal conductivity is maintained at a low level,leading to an extraordinary figure-of-merit(ZT)value of∼1.3 at room temperature.Furthermore,the Bi_(2)Zn_(0.01)Te_(2.79)Se_(0.21)I_(0.004) system demonstrates impressive thermoelectric device performance,with a maximum cooling temperature difference(ΔT_(max))of∼70.0 K at 300 K,rising to∼78.0 K at 323 K and∼85.7 K at 343 K,as well as a maximum conversion efficiency(η_(max))of∼6.2%under aΔT of 200 K.This study clarifies the mechanism of Zn doping and presents a cost-effective strategy for enhancing the performance of n-type BTS thermoelectrics and their devices.
基金financial support to conduct this research from the Science and Engineering Research Board(SERB)through a state university research excellence(SURE)grant(SUR/2022/004935).
文摘Density functional theory(DFT)calculations were employed to investigate the adsorption behavior of NH_(3),AsH_(3),PH_(3),CO_(2),and CH_(4)molecules on both pristine and mono-vacancy phosphorene sheets.The pristine phosphorene surface showsweak physisorption with all the gasmolecules,inducing onlyminor changes in its structural and electronic properties.However,the introduction ofmono-vacancies significantly enhances the interaction strength with NH_(3),PH_(3),CO_(2),and CH_(4).These variations are attributed to substantial charge redistribution and orbital hybridization in the presence of defects.The defective phosphorene sheet also exhibits enhanced adsorption energies,along with favorable sensitivity and recovery characteristics,highlighting its potential as a promising gas sensor for NH_(3),AsH_(3),PH_(3),CO_(2),and CH_(4)at ambient conditions.
文摘The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the originally assigned pages(2595-2614),we will need to publish an erratum to correct the article and restore the original page range.The original article has been corrected.
基金supported by the National Natural Science Foundation of China(Nos.51778618 and 52070192)the National Water Pollution Control and Treatment Science and Technology Major Project(No.2017ZX07102).
文摘Algal blooms in eutrophic water often produce microcystins,which can lead to multi-organ dysfunction and even mortality in many organisms.Therefore,the elimination of microcystins in water is an urgent issue that needs to be addressed.Herein,we develop a dual defect engineering strategy to construct graphite-like carbon nitride with N vacancies and-C≡N groups(NgCN)nanosheets for microcystin-LR(MC-LR)photodegradation.According to our theoretical calculations and actual findings,the NgCN nanosheets enhanced recyclability for the removal of MC-LR while also demonstrating outstanding photocatalytic efficacy,significantly surpassing the graphite-like carbon nitride under visible light,which is ascribed to efficient charge separation as well as narrowing the bandgap.Impressively,the water quality after photodegradation has been proven to be safe based on International Organization for Standardization(ISO)standards.This finding provides meaningful insights into understanding the relationship between defect engineering and photodegradation performance to design photocatalytic materials with higher activity for environmental remediation.
基金supported by the National Natural Science Foundation of China(No.52403035)the Shanghai Sailing Program(23YF1400300)+1 种基金the Fundamental Research Funds for the Central Universities(2232023D-05)the Weiqiao Teaching and Research Innovation Program.
文摘The lack of macro-continuity and mechanical strength of covalent organic frameworks(COFs)has significantly limited their practical applications.Here,we propose an“alcohol-triggered defect cleavage”strategy to precisely regulate the growth and stacking of COF grains through a moderate reversed Schiff base reaction,realizing the direct synthesis of COF nanofibers(CNFs)with high aspect ratio(L/D=103.05)and long length(>20μm).An individual CNF exhibits a biomimetic scale-like architecture,achieving superior flexibility and fatigue resistance under dynamic bending via a multiscale stress dissipation mechanism.Taking advantages of these structural features,we engineer CNF aerogels(CNF-As)with programmable porous structures(e.g.,honeycomb,lamellar,isotropic)via directional ice-template methodology.CNF-As demonstrate 100%COF content,high specific surface area(396.15 m^(2)g^(-1))and superelasticity(~0%elastic deformation after 500 compression cycles at 50%strain),outperforming most COF-based counterparts.Compared with the conventional COF aerogels,the unique structural features of CNF-A enable it to perform outstandingly in uranium extraction,with an 11.72-fold increment in adsorption capacity(920.12 mg g^(-1))and adsorption rate(89.9%),and a 2.48-fold improvement in selectivity(U/V=2.31).This study provides a direct strategy for the development of next-generation COF materials with outstanding functionality and structural robustness.
基金supported by the National Key Research and Development Program of China(2023YFD2200505)National Natural Science Foundation of China(22202105),Natural Science Foundation of Jiangsu Higher Education Institutions of China(21KJA150003)the Innovation and Entrepreneurship Team Program of Jiangsu Province(JSSCTD202345).
文摘Photocatalytic transfer hydrogenation using water as the proton source has emerged as an attractive and green approach for the catalytic reduction of unsaturated bonds.Herein,we report an oxygen-defective TiO_(2)-supported palladium catalyst(Pd-TiO_(2)-Ov)for efficient photocatalytic water-donating transfer hydrogenation of anethole towards 4-n-propylanisole in a high yield of 99.9%,which is significantly higher compared to the pristine TiO_(2)-supported palladium catalyst(Pd-TiO_(2),74%).The enhanced performance is ascribed to the presence of oxygen vacancies,which facilitate light absorption and suppress the recombination of photogenerated electron-hole pairs.Furthermore,the Pd-TiO_(2)-Ov is versatile in hydrogenating various alkene substrates including those with hydroxyl,ether,fluoride,and chloride functional groups in full conversion,thus offering a green method for transfer hydrogenation of alkenes.This study provides new insights and advances in current hydrogenation technology with water as the proton source.
基金Project(2023YFB4606200)supported by the National Key Research and Development Program of ChinaProject(2023-SSRF-HZ-503114-2)supported by Shanghai Synchrotron Radiation Facility,Instrument BL16U2,China。
文摘This comprehensive study investigates the formation and evolution of intermetallic compounds during the solidification process of magnesium alloys using advanced micro X-ray computed tomography.By analyzing both common industrial Mg-Al-Zn alloys and a novel rare earth-containing Mg-Ni-Gd-Y alloy,we aim to characterize the nucleation,growth,and distribution of Al-Mn and eutectic intermetallics across various stages of solidification.The non destructive imaging technique employed in this research provides high-resolution,three-dimensional insights into the microstructural development,allowing for a detailed examination of the morphology,spatial arrangement,and interconnectivity of intermetallic phases.This approach overcomes limitations of traditional two-dimensional metallographic methods,offering a more comprehensive understanding of the complex three-dimensional structures formed during solidification.
基金financial support from the National Key Research and Development Program of China(No.2024YFE0103600)the National Natural Science Foundation of China(No.52273189)+5 种基金the Natural Science Foundation of Jiangsu Province(Nos.BG2024016,BZ2023052,BE2022026-2,BK20240756)the Natural Science Foundation of Anhui Province(No.202423h08050004)the China Postdoctoral Science Foundation(Nos.2024T170622,2023M742526,GZB20240518)the Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2024ZB061)the Suzhou science and technology plan project(Nos.ST202212,ST202312)supported by the Suzhou Key Laboratory of Functional Nano&Soft Materials。
文摘The transition of perovskite solar cells(PSCs)from laboratory-scale devices to large-area commercial modules is fundamentally challenged by the poor uniformity and repeatability of conventional solution-based surface passivation.To overcome this critical bottleneck,we introduce a vacuumevaporated passivation strategy using the thermally evaporable molecule bathophenanthroline(BPhen).This solvent-free approach yields highly uniform passivation layers,effectively suppressing surface defects and enhancing charge extraction through synergistic π-π stacking with the C60 electron transport layer.Our fully vacuum-evaporated PSCs achieve a remarkable power conversion efficiency(PCE)of 20.13%for champion cells and 18.42%for 5 cm×5 cm mini-modules.These results not only demonstrate the superiority of evaporated passivation for fabricating large-area devices but also establish a scalable and robust engineering pathway toward the commercial production of highperformance perovskite photovoltaics.
文摘Proton-conducting oxides constitute a wide class of materials that exhibit pronounced proton transport in humid atmospheres.Owing to their high proton mobility,these oxides are regarded as promising electrolytes for low-and intermediate-temperature protonic ceramic fuel cells and electrolysis cells,which offer efficient and clean energy conversion.Protons appear in complex oxides through a dissociative water adsorption process,which consists of the interaction between existing oxygen vacancies and water molecules in the gas phase.This process is also known as hydration or water uptake.Within the present work,we analyze the hydration features of BaSn_(1-x)In_(x)O_(3-δ)perovskite materials(BSIx),which include a wide range of solid solutions(0≤x<0.7)and a nearly theoretical hydration limit for almost all studied compounds at the same time.The latter is a unique property of In-doped stannates,which is untypical for most other proton-conducting oxides.Along with the experimental data on the water uptake of BSIx,we provide an in-depth investigation of proton concentrations depending on external factors,involving a further comparison with literature data on materials hydration,as well as the discovery of hidden relationships between proton concentration and various functional properties.Therefore,this work contributes to theoretical and applied investigations of proton-conducting oxides,especially in the context of their hydration behavior.
基金supported by the National Natural Science Foundation of China(Grant No.62205103)the Natural Science Foundation of Hunan Province(Grant No.2023JJ40216)the Elite Youth Program by the Department of Education of Hunan Province(Grant No.24B0663)。
文摘Although the certified power conversion efficiency(PCE)of single-junction perovskite solar cells(PSCs)has achieved a high level of 27%,approaching the single-crystalline silicon solar cells,the device stability remains an urgent issue to be resolved for the commercialization.Defect passivation emerged as a viable approach to enhance the operational stability of the solar devices.Herein,phenylthiourea(PhTu)derivatives are selected as effective passivation agents to enhance the optoelectronic properties of printed methylammonium lead iodide(MAPbI_(3))films.It is demonstrated that incorporating a small amount of 1-(4-carboxyphenyl)-2-thiourea(PhTu-COOH)significantly reduces the trap-state density and leads to longer carrier lifetime of the perovskite films.As a result,the inverted solar device made of Ph Tu-COOH-modified MAPbI_(3) perovskite film shows remarkably improved efficiency(from 17.29%to 20.22%)and obviously increased open-circuit voltage(V_(OC))(from 1.043 to 1.143 V),as compared with the pristine device.Moreover,the Ph Tu-COOH-modified PSCs exhibit enhanced operational stability due to the significantly reduced trap-state density.Finally,the optimized solar module fabricated with an active area of 11.28 cm^(2) delivers a high PCE of 17.07%with negligible V_(OC)loss,demonstrating the feasibility of the blade-coating method for large-area perovskite film deposition.
基金supported and funded by the Deanship of Scientific Research at Imam Mohammad Ibn Saud Islamic University(IMSIU)(Grant number IMSIU-DDRSP2603)。
文摘A parametric study was performed to explore the effect of runner thickness,filtration,and hydrogen content on the mechanical properties and defect formation in Al-7%Si-0.3%Mg(2L99)sand castings.A two-level full factorial design of experiments was used to statistically evaluate these parameters and the tensile properties were characterized via Weibull distribution analysis.The findings reveal that decreasing the runner thickness from25 mm to 10 mm and using 10 PPI ceramic filters improve mechanical properties by minimizing double oxide film entrainment as confirmed by electron microscopy examination.In addition,lowering hydrogen concentrations within the Al alloy from 0.24 cm^(3)/100 g Al to 0.12 cm^(3)/100 g Al is also shown to enhance casting integrity by suppressing bifilm inflation and subsequent pore formation.ANOVA results indicate that the hydrogen content is the most important factor,contributing 53%to the variability in mechanical properties,followed by filtration(25%)and runner thickness(17%).The optimized casting conditions including thin runners(10 mm thick),melt filtration,and a low hydrogen level(0.12 cm^(3)/100 g Al),result in an approximately 474%increase in the shape factor and a 107%increase in the characteristic life of UTS,as well as an approximately 413%increase in the shape factor and a 149%increase in characteristic life of elongation.The outcomes suggest that controlled filling systems and melt treatment are critical for producing consistent,high integrity aluminum castings in industrial applications.
基金funded by the National Natural Science Foundation of China (No. 52372037)the Natural Science Foundation of Anhui Province (Nos. 2408085MB032)+1 种基金the Outstanding Scientific Research and Innovation Team Program of Higher Education Institutions of Anhui Province (No. 2023AH010015)support from the Anhui International Research Center of Energy Materials Green Manufacturing and Biotechnology
文摘Metal-organic framework(MOF)-derived porous carbon has attracted particular attention in the electrochemical energy storage field,of which the key is the design and preparation of electrode materials with adjustable porosity and defects for supercapacitors.Here,a novel strategy of coating ZIF-8 with coal tar pitch(CTP)is presented to tailor the porosity and defects of derived porous carbon,by which the inward contraction of ZIF-8 is prevented to enlarge the ultra-micropores,and the defects of ZIF-8-derived carbon are repaired to form a continuous conjugated network.The tradeoff between porosity and electrical conductivity endows this novel hard/soft carbon electrode with fast ion/electron diffusion,achieving high yet balanced capacitance and rate performance of a top-level specific area-normalized capacitance(40μF cm^(-2))and a capacitance retention of 52.1%at a 1000-fold increased current density.Meanwhile,the novel electrode realizes a high capacitance of 704 F g^(-1)at 1 A g^(-1)and capacitance retention of 91.9%after 50000 cycles in KOH+PPD electrolyte.This study provides an effective approach to designing novel hard/soft carbon with tuned porosity and carbon defects from MOFs and CTP for supercapacitors and other metal-ion batteries.
基金financially supported by the Fujian Provincial Department of Science and Technology,the Collaborative Innovation Platform Project for Key Technologies of Smart Warehousing and Logistics Systems in the Fuzhou-Xiamen-Quanzhou National Independent Innovation Demonstration Zone(No.2025E3024).
文摘Fabric defect detection plays a vital role in ensuring textile quality.However,traditional manual inspection methods are often inefficient and inaccurate.To overcome these limitations,we propose FD-YOLO,an enhanced lightweight detection model based on the YOLOv11n framework.The proposed model introduces the Bi-level Routing Attention(BRAttention)mechanism to enhance defect feature extraction,enabling more detailed feature representation.It proposes Deep Progressive Cross-Scale Fusion Neck(DPCSFNeck)to better capture smallscale defects and incorporates a Multi-Scale Dilated Residual(MSDR)module to strengthen multi-scale feature representation.Furthermore,a Shared Detail-Enhanced Lightweight Head(SDELHead)is employed to reduce the risk of gradient explosion during training.Experimental results demonstrate that FD-YOLO achieves superior detection accuracy and Lightweight performance compared to the baseline YOLOv11n.
基金supported by the State Grid Southwest Branch Project“Research on Defect Diagnosis and Early Warning Technology of Relay Protection and Safety Automation Devices Based on Multi-Source Heterogeneous Defect Data”.
文摘The reliable operation of power grid secondary equipment is an important guarantee for the safety and stability of the power system.However,various defects could be produced in the secondary equipment during longtermoperation.The complex relationship between the defect phenomenon andmulti-layer causes and the probabilistic influence of secondary equipment cannot be described through knowledge extraction and fusion technology by existing methods,which limits the real-time and accuracy of defect identification.Therefore,a defect recognition method based on the Bayesian network and knowledge graph fusion is proposed.The defect data of secondary equipment is transformed into the structured knowledge graph through knowledge extraction and fusion technology.The knowledge graph of power grid secondary equipment is mapped to the Bayesian network framework,combined with historical defect data,and introduced Noisy-OR nodes.The prior and conditional probabilities of the Bayesian network are then reasonably assigned to build a model that reflects the probability dependence between defect phenomena and potential causes in power grid secondary equipment.Defect identification of power grid secondary equipment is achieved by defect subgraph search based on the knowledge graph,and defect inference based on the Bayesian network.Practical application cases prove this method’s effectiveness in identifying secondary equipment defect causes,improving identification accuracy and efficiency.
