Conductive polymer foam(CPF)with excellent compressibility and variable resistance has promising applications in electromagnetic interference(EMI)shielding and other integrated functions for wearable electronics.Howev...Conductive polymer foam(CPF)with excellent compressibility and variable resistance has promising applications in electromagnetic interference(EMI)shielding and other integrated functions for wearable electronics.However,its insufficient change amplitude of resistance with compressive strain generally leads to a degradation of shielding performance during deformation.Here,an innovative loading strategy of conductive materials on polymer foam is proposed to significantly increase the contact probability and contact area of conductive components under compression.Unique inter-skeleton conductive films are constructed by loading alginate-decorated magnetic liquid metal on the polymethacrylate films hanged between the foam skeleton(denoted as AMLM-PM foam).Traditional point contact between conductive skeletons under compression is upgraded to planar contact between conductive films.Therefore,the resistance change of AMLM-PM reaches four orders of magnitude under compression.Moreover,the inter-skeleton conductive films can improve the mechanical strength of foam,prevent the leakage of liquid metal and increase the scattering area of EM wave.AMLM-PM foam has strain-adaptive EMI shielding performance and shows compression-enhanced shielding effectiveness,solving the problem of traditional CPFs upon compression.The upgrade of resistance response also enables foam to achieve sensitive pressure sensing over a wide pressure range and compression-regulated Joule heating function.展开更多
Digital technologies have become an integral part of complete denture restoration.With advancement in computer-aided design and computer-aided manufacturing(CAD/CAM),tools such as intraoral scanning,facial scanning,3D...Digital technologies have become an integral part of complete denture restoration.With advancement in computer-aided design and computer-aided manufacturing(CAD/CAM),tools such as intraoral scanning,facial scanning,3D printing,and numerical control machining are reshaping the workflow of complete denture restoration.Unlike conventional methods that rely heavily on clinical experience and manual techniques,digital technologies offer greater precision,predictability,and efficacy.They also streamline the process by reducing the number of patient visits and improving overall comfort.Despite these improvements,the clinical application of digital complete denture restoration still faces challenges that require further standardization.The major issues include appropriate case selection,establishing consistent digital workflows,and evaluating long-term outcomes.To address these challenges and provide clinical guidance for practitioners,this expert consensus outlines the principles,advantages,and limitations of digital complete denture technology.The aim of this review was to offer practical recommendations on indications,clinical procedures and precautions,evaluation metrics,and outcome assessment to support digital restoration of complete denture in clinical practice.展开更多
Electromagnetic interference(EMI)shielding materials with adaptive strain capability have broad applications in wearable electronic devices.However,as an important candidate,compressible conductive foam generally suff...Electromagnetic interference(EMI)shielding materials with adaptive strain capability have broad applications in wearable electronic devices.However,as an important candidate,compressible conductive foam generally suffers from a reduction in EMI shielding performance during compression,which limits its application.Here,a compressible conductive aerogel with a unique conductive compensation effect is designed to solve this problem.CuS microspheres with metal-like conductivity serve as conductive compensation sites,and are chemically embedded in the skeletons of lamellar-structured carboxymethylcellulose(CMC)/MXene aerogel through Cu–S−Ti−C chemical bonds.The incorporation of CuS induces circularly-distributed interfacial polarization to enhance the attenuation of EM waves.More importantly,these CuS microspheres act as interlayer bridges to connect the upper and lower MXene/CMC layers during compression,thereby establishing numerous conductive compensation paths to offset the negative effect of thickness reduction on shielding performance.The optimized CMC/MXene/CuS aerogel shows stable EMI shielding performance during compression,and maintains a high shielding effectiveness of∼32.31 dB with increasing compressive strain.In addition,this composite aerogel exhibits good thermal insulation and sound absorption performances,achieving triple shielding functions against EM waves,heat and sound.展开更多
Despite the cost and activity advantages,ruthenium-based oxygen evolution reaction(OER)catalysts face severe stability problems for proton exchange membrane water electrolysis(PEM-WE)due to Ru dissolution.Although tre...Despite the cost and activity advantages,ruthenium-based oxygen evolution reaction(OER)catalysts face severe stability problems for proton exchange membrane water electrolysis(PEM-WE)due to Ru dissolution.Although tremendous attention has been paid to enhancing the stability and activity under small current density in three electrode systems,there still lacks validation under industrial current density at the device level.Aiming at this issue,we report highly active and durable ruthenium-iridium alloyed oxides(IrRuO_(x))as the acidic OER catalyst for PEM-WE with exceptional durability for 1600 h at an industrial current density of 2.0 A·cm^(−2).X-ray absorption spectroscopy reveals that the introduction of iridium modulates the electronic structure of Ru and strengthens the local Ru–O bonds in RuO_(2),which is crucial for ensuring activity and stability.As a result,in comparison with its RuO_(2) counterpart,IrRuO_(x) works stably against the Ru leaching-induced catalytic layer breakage during the stability test.This work demonstrates the great potential of IrRuO_(x) as the practical OER catalyst for the application in PEM-WE.展开更多
Our previous studies showed that biomodification of demineralized dentin collagen with proanthocyanidin（PA） for a clinically practical duration improves the mechanical properties of the dentin matrix and the immedia...Our previous studies showed that biomodification of demineralized dentin collagen with proanthocyanidin（PA） for a clinically practical duration improves the mechanical properties of the dentin matrix and the immediate resin–dentin bond strength. The present study sought to evaluate the ability of PA biomodification to reduce collagenase-induced biodegradation of demineralized dentin matrix and dentin/adhesive interfaces in a clinically relevant manner. The effects of collagenolytic and gelatinolytic activity on PA-biomodified demineralized dentin matrix were analysed by hydroxyproline assay and gelatin zymography. Then, resin-/dentin-bonded specimens were prepared and challenged with bacterial collagenases. Dentin treated with 2% chlorhexidine and untreated dentin were used as a positive and negative control, respectively. Collagen biodegradation, the microtensile bond strengths of bonded specimens and the micromorphologies of the fractured interfaces were assessed. The results revealed that both collagenolytic and gelatinolytic activity on demineralized dentin were notably inhibited in the PA-biomodified groups, irrespective of PA concentration and biomodification duration. When challenged with exogenous collagenases, PA-biomodified bonded specimens exhibited significantly less biodegradation and maintained higher bond strengths than the untreated control. These results suggest that PA biomodification was effective at inhibiting proteolytic activity on demineralized dentin matrix and at stabilizing the adhesive/dentin interface against enzymatic degradation, is a new concept that has the potential to improve bonding durability.展开更多
基金supported by National Key Research and Development Program of China(2021YBF3501304)National Natural Science Foundation of China(52222106,52371171,51971008,52121001)Natural Science Foundation of Beijing Municipality(2212033).
文摘Conductive polymer foam(CPF)with excellent compressibility and variable resistance has promising applications in electromagnetic interference(EMI)shielding and other integrated functions for wearable electronics.However,its insufficient change amplitude of resistance with compressive strain generally leads to a degradation of shielding performance during deformation.Here,an innovative loading strategy of conductive materials on polymer foam is proposed to significantly increase the contact probability and contact area of conductive components under compression.Unique inter-skeleton conductive films are constructed by loading alginate-decorated magnetic liquid metal on the polymethacrylate films hanged between the foam skeleton(denoted as AMLM-PM foam).Traditional point contact between conductive skeletons under compression is upgraded to planar contact between conductive films.Therefore,the resistance change of AMLM-PM reaches four orders of magnitude under compression.Moreover,the inter-skeleton conductive films can improve the mechanical strength of foam,prevent the leakage of liquid metal and increase the scattering area of EM wave.AMLM-PM foam has strain-adaptive EMI shielding performance and shows compression-enhanced shielding effectiveness,solving the problem of traditional CPFs upon compression.The upgrade of resistance response also enables foam to achieve sensitive pressure sensing over a wide pressure range and compression-regulated Joule heating function.
基金supported by National Natural Science Foundation of China(82325012)General project of State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration(2024MS05).
文摘Digital technologies have become an integral part of complete denture restoration.With advancement in computer-aided design and computer-aided manufacturing(CAD/CAM),tools such as intraoral scanning,facial scanning,3D printing,and numerical control machining are reshaping the workflow of complete denture restoration.Unlike conventional methods that rely heavily on clinical experience and manual techniques,digital technologies offer greater precision,predictability,and efficacy.They also streamline the process by reducing the number of patient visits and improving overall comfort.Despite these improvements,the clinical application of digital complete denture restoration still faces challenges that require further standardization.The major issues include appropriate case selection,establishing consistent digital workflows,and evaluating long-term outcomes.To address these challenges and provide clinical guidance for practitioners,this expert consensus outlines the principles,advantages,and limitations of digital complete denture technology.The aim of this review was to offer practical recommendations on indications,clinical procedures and precautions,evaluation metrics,and outcome assessment to support digital restoration of complete denture in clinical practice.
基金financially supported by the National Key Research and Development Program of China(No.2021YBF3501304)the National Natural Science Foundation of China(Nos.52371171,52222106,51971008,52121001)+1 种基金the Natural Science Foundation of Beijing Municipality(No.2212033)We thank the researchers at the Analysis&Testing Center of Beihang University for their assistance with testing.
文摘Electromagnetic interference(EMI)shielding materials with adaptive strain capability have broad applications in wearable electronic devices.However,as an important candidate,compressible conductive foam generally suffers from a reduction in EMI shielding performance during compression,which limits its application.Here,a compressible conductive aerogel with a unique conductive compensation effect is designed to solve this problem.CuS microspheres with metal-like conductivity serve as conductive compensation sites,and are chemically embedded in the skeletons of lamellar-structured carboxymethylcellulose(CMC)/MXene aerogel through Cu–S−Ti−C chemical bonds.The incorporation of CuS induces circularly-distributed interfacial polarization to enhance the attenuation of EM waves.More importantly,these CuS microspheres act as interlayer bridges to connect the upper and lower MXene/CMC layers during compression,thereby establishing numerous conductive compensation paths to offset the negative effect of thickness reduction on shielding performance.The optimized CMC/MXene/CuS aerogel shows stable EMI shielding performance during compression,and maintains a high shielding effectiveness of∼32.31 dB with increasing compressive strain.In addition,this composite aerogel exhibits good thermal insulation and sound absorption performances,achieving triple shielding functions against EM waves,heat and sound.
基金supported by the National Key Research and Development Program of China(No.2021YFA1500400)the National Natural Science Foundation of China(No.22175163)+3 种基金the Natural Science Foundation of Anhui Province(No.2208085UD04)Anhui Development and Reform Commission(Nos.AHZDCYCX-LSDT2023-08 and AHZDCYCX-LSDT2023-07)the Department of Ecology and Environment of Anhui Province(No.2023hb0018)the Fundamental Research Funds for the Central Universities(No.WK2060000016).
文摘Despite the cost and activity advantages,ruthenium-based oxygen evolution reaction(OER)catalysts face severe stability problems for proton exchange membrane water electrolysis(PEM-WE)due to Ru dissolution.Although tremendous attention has been paid to enhancing the stability and activity under small current density in three electrode systems,there still lacks validation under industrial current density at the device level.Aiming at this issue,we report highly active and durable ruthenium-iridium alloyed oxides(IrRuO_(x))as the acidic OER catalyst for PEM-WE with exceptional durability for 1600 h at an industrial current density of 2.0 A·cm^(−2).X-ray absorption spectroscopy reveals that the introduction of iridium modulates the electronic structure of Ru and strengthens the local Ru–O bonds in RuO_(2),which is crucial for ensuring activity and stability.As a result,in comparison with its RuO_(2) counterpart,IrRuO_(x) works stably against the Ru leaching-induced catalytic layer breakage during the stability test.This work demonstrates the great potential of IrRuO_(x) as the practical OER catalyst for the application in PEM-WE.
基金supported by research funds from the Natural Science Foundation of China (No. 81130078 and No. 81000458)Program for Changjiang Scholars and Innovative Research Team in University (No. IRT13051)
文摘Our previous studies showed that biomodification of demineralized dentin collagen with proanthocyanidin（PA） for a clinically practical duration improves the mechanical properties of the dentin matrix and the immediate resin–dentin bond strength. The present study sought to evaluate the ability of PA biomodification to reduce collagenase-induced biodegradation of demineralized dentin matrix and dentin/adhesive interfaces in a clinically relevant manner. The effects of collagenolytic and gelatinolytic activity on PA-biomodified demineralized dentin matrix were analysed by hydroxyproline assay and gelatin zymography. Then, resin-/dentin-bonded specimens were prepared and challenged with bacterial collagenases. Dentin treated with 2% chlorhexidine and untreated dentin were used as a positive and negative control, respectively. Collagen biodegradation, the microtensile bond strengths of bonded specimens and the micromorphologies of the fractured interfaces were assessed. The results revealed that both collagenolytic and gelatinolytic activity on demineralized dentin were notably inhibited in the PA-biomodified groups, irrespective of PA concentration and biomodification duration. When challenged with exogenous collagenases, PA-biomodified bonded specimens exhibited significantly less biodegradation and maintained higher bond strengths than the untreated control. These results suggest that PA biomodification was effective at inhibiting proteolytic activity on demineralized dentin matrix and at stabilizing the adhesive/dentin interface against enzymatic degradation, is a new concept that has the potential to improve bonding durability.
