The architectural design of electrodes offers new opportunities for next-generation electrochemical energy storage devices(EESDs)by increasing surface area,thickness,and active materials mass loading while maintaining...The architectural design of electrodes offers new opportunities for next-generation electrochemical energy storage devices(EESDs)by increasing surface area,thickness,and active materials mass loading while maintaining good ion diffusion through optimized electrode tortuosity.However,conventional thick electrodes increase ion diffusion length and cause larger ion concentration gradients,limiting reaction kinetics.We demonstrate a strategy for building interpenetrated structures that shortens ion diffusion length and reduces ion concentration inhomogeneity.This free-standing device structure also avoids short-circuiting without needing a separator.The feature size and number of interpenetrated units can be adjusted during printing to balance surface area and ion diffusion.Starting with a 3D-printed interpenetrated polymer substrate,we metallize it to make it conductive.This substrate has two individually addressable electrodes,allowing selective electrodeposition of energy storage materials.Using a Zn//MnO_(2) battery as a model system,the interpenetrated device outperforms conventional separate electrode configurations,improving volumetric energy density by 221%and exhibiting a higher capacity retention rate of 49%compared to 35%at temperatures from 20 to 0℃.Our study introduces a new EESD architecture applicable to Li-ion,Na-ion batteries,supercapacitors,etc.展开更多
Enhancing the lifetime of perovskite solar cells(PSCs)is one of the essential challenges for their industrialization.Although the external encapsulation protects the perovskite device from the erosion of moisture and ...Enhancing the lifetime of perovskite solar cells(PSCs)is one of the essential challenges for their industrialization.Although the external encapsulation protects the perovskite device from the erosion of moisture and oxygen under various harsh conditions.However,the perovskite devices still undergo static and dynamic thermal stress during thermal and thermal cycling aging,respectively,resulting in irreversible damage to the morphology,component,and phase of stacked materials.Herein,the viscoelastic polymer polyvinyl butyral(PVB)material is designed onto the surface of perovskite films to form flexible interface encapsulation.After PVB interface encapsulation,the surface modulus of perovskite films decreases by nearly 50%,and the interface stress range under the dynamic temperature field(−40 to 85°C)drops from−42.5 to 64.8 MPa to−14.8 to 5.0 MPa.Besides,PVB forms chemical interactions with FA+cations and Pb^(2+),and the macroscopic residual stress is regulated and defects are reduced of the PVB encapsulated perovskite film.As a result,the optimized device's efficiency increases from 22.21%to 23.11%.Additionally,after 1500 h of thermal treatment(85°C),1000 h of damp heat test(85°C&85%RH),and 250 cycles of thermal cycling test(−40 to 85°C),the devices maintain 92.6%,85.8%,and 96.1%of their initial efficiencies,respectively.展开更多
Perovskite solar cell has gained widespread attention as a promising technology for renewable energy.However, their commercial viability has been hampered by their long-term stability and potential Pb leakage. Herein,...Perovskite solar cell has gained widespread attention as a promising technology for renewable energy.However, their commercial viability has been hampered by their long-term stability and potential Pb leakage. Herein, we demonstrate a bifunctional passivator of the potassium tartrate(PT) to address both challenges. PT minimizes the Pb leakage in perovskites and also heals cationic vacancy defects, resulting in improved device performance and stability. Benefiting from PT modification, the power conversion efficiency(PCE) is improved to 23.26% and the Pb leakage in unencapsulated films is significantly reduced to 9.79 ppm. Furthermore, the corresponding device exhibits no significant decay in PCE after tracking at the maximum power point(MPP) for 2000 h under illumination(LED source, 100 mW cm^(-2)).展开更多
BACKGROUND Targeting DNA damage response(DDR)pathway is a cutting-edge strategy.It has been reported that Schlafen-11(SLFN11)contributes to increase chemosensitivity by participating in DDR.However,the detailed mechan...BACKGROUND Targeting DNA damage response(DDR)pathway is a cutting-edge strategy.It has been reported that Schlafen-11(SLFN11)contributes to increase chemosensitivity by participating in DDR.However,the detailed mechanism is unclear.AIM To investigate the role of SLFN11 in DDR and the application of synthetic lethal in esophageal cancer with SLFN11 defects.METHODS To reach the purpose,eight esophageal squamous carcinoma cell lines,142 esophageal dysplasia(ED)and 1007 primary esophageal squamous cell carcinoma(ESCC)samples and various techniques were utilized,including methylationspecific polymerase chain reaction,CRISPR/Cas9 technique,Western blot,colony formation assay,and xenograft mouse model.RESULTS Methylation of SLFN11 was exhibited in 9.15%of(13/142)ED and 25.62%of primary(258/1007)ESCC cases,and its expression was regulated by promoter region methylation.SLFN11 methylation was significantly associated with tumor differentiation and tumor size(both P<0.05).However,no significant associations were observed between promoter region methylation and age,gender,smoking,alcohol consumption,TNM stage,or lymph node metastasis.Utilizing DNA damaged model induced by low dose cisplatin,SLFN11 was found to activate non-homologous end-joining and ATR/CHK1 signaling pathways,while inhibiting the ATM/CHK2 signaling pathway.Epigenetic silencing of SLFN11 was found to sensitize the ESCC cells to ATM inhibitor(AZD0156),both in vitro and in vivo.CONCLUSION SLFN11 is frequently methylated in human ESCC.Methylation of SLFN11 is sensitive marker of ATM inhibitor in ESCC.展开更多
The performance of proton exchange membrane fuel cells is heavily dependent on the microstructure of electrode catalyst especially at low catalyst loadings.This work shows a hybrid electrocatalyst consisting of PtNi-W...The performance of proton exchange membrane fuel cells is heavily dependent on the microstructure of electrode catalyst especially at low catalyst loadings.This work shows a hybrid electrocatalyst consisting of PtNi-W alloy nanocrystals loaded on carbon surface with atomically dispersed W sites by a two-step straightforward method.Single-atomic W can be found on the carbon surface,which can form protonic acid sites and establish an extended proton transport network at the catalyst surface.When implemented in membrane electrode assembly as cathode at ultra-low loading of 0.05 mgPt cm^(−2),the peak power density of the cell is enhanced by 64.4%compared to that with the commercial Pt/C catalyst.The theoretical calculation suggests that the single-atomic W possesses a favorable energetics toward the formation of*OOH whereby the intermediates can be efficiently converted and further reduced to water,revealing a interfacial cascade catalysis facilitated by the single-atomic W.This work highlights a novel functional hybrid electrocatalyst design from the atomic level that enables to solve the bottle-neck issues at device level.展开更多
To achieve high power conversion efficiency(PCE) and long-term stability of perovskite solar cells(PSCs), a hole transport layer(HTL) with persistently high conductivity, good moisture/oxygen barrier ability, and adeq...To achieve high power conversion efficiency(PCE) and long-term stability of perovskite solar cells(PSCs), a hole transport layer(HTL) with persistently high conductivity, good moisture/oxygen barrier ability, and adequate passivation capability is important. To achieve enough conductivity and effective hole extraction, spiro-OMe TAD, one of the most frequently used HTL in optoelectronic devices, often needs chemical doping with a lithium compound(LiTFSI). However, the lithium salt dopant induces crystallization and has a negative impact on the performance and lifetime of the device due to its hygroscopic nature. Here, we provide an easy method for creating a gel by mixing a natural small molecule additive(thioctic acid, TA) with spiro-OMe TAD. We discover that gelation effectively improves the compactness of resultant HTL and prevents moisture and oxygen infiltration. Moreover, the gelation of HTL improves not only the conductivity of spiro-OMe TAD, but also the operational robustness of the devices in the atmospheric environment. In addition, TA passivates the perovskite defects and facilitates the charge transfer from the perovskite layer to HTL. As a consequence, the optimized PSCs based on the gelated HTL exhibit an improved PCE(22.52%) with excellent device stability.展开更多
Flexible perovskite solar cells have attracted widespread attention due to their unique advantages in lightweight,high flexibility,and easy deformation,which are suitable for portable electronics.However,the inverted(...Flexible perovskite solar cells have attracted widespread attention due to their unique advantages in lightweight,high flexibility,and easy deformation,which are suitable for portable electronics.However,the inverted(p-i-n)structured devices suffer from poor stability largely due to the low adhesion at the brittle interface(the hole transport layer/perovskite).Herein,zeolitic imidazolate framework-67(ZIF-67)is applied to inverted structured cells to optimize the interface and prolong the device lifetime.As a result,the flexible devices based on ZIF-67 obtain the champion power conversion efficiency of 20.16%.Over 1000 h under continuous light irradiation,the device retains 96%and 80%of its original efficiency without and with bias,respectively.Notably,devices show mechanical endurance with over 78%efficiency retention after 10,000 cycles of consecutive bending cycles(R=6 mm).The introduction of ZIF-67 suppresses the cracking in device bending,which results in improved environmental stability and bending durability.展开更多
In the field of speech bandwidth exten-sion,it is difficult to achieve high speech quality based on the shallow statistical model method.Although the application of deep learning has greatly improved the extended spee...In the field of speech bandwidth exten-sion,it is difficult to achieve high speech quality based on the shallow statistical model method.Although the application of deep learning has greatly improved the extended speech quality,the high model complex-ity makes it infeasible to run on the client.In order to tackle these issues,this paper proposes an end-to-end speech bandwidth extension method based on a temporal convolutional neural network,which greatly reduces the complexity of the model.In addition,a new time-frequency loss function is designed to en-able narrowband speech to acquire a more accurate wideband mapping in the time domain and the fre-quency domain.The experimental results show that the reconstructed wideband speech generated by the proposed method is superior to the traditional heuris-tic rule based approaches and the conventional neu-ral network methods for both subjective and objective evaluation.展开更多
Taking the practice status of professional master’s degree candidates for agriculture in Anhui Agricultural University as an example,this paper analyzes the key factors affecting the practical training of graduate st...Taking the practice status of professional master’s degree candidates for agriculture in Anhui Agricultural University as an example,this paper analyzes the key factors affecting the practical training of graduate students in this major,and puts forward some strategies for improving the practice quality of professional master’s degree candidates.In terms of training professional master’s degree candidates,it is considered that agricultural colleges and universities should start with collaborative education,supervision and assessment mechanism,practice content and form,make full use of a large number of agricultural enterprise resources owned by colleges and universities and a good cooperation foundation in enterprises,so as to achieve the purpose of improving the practice quality of professional master’s degree candidates.展开更多
基金financial support from the Center for Coastal Climate Resilience of the University of California,Santa Cruz(UCSC)This work was performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under Contract No.DE-AC52-07NA27344 and supported by Laboratory Directed Research and Development award 23-SI-002.IM release number:LLNL-JRNL-862347。
文摘The architectural design of electrodes offers new opportunities for next-generation electrochemical energy storage devices(EESDs)by increasing surface area,thickness,and active materials mass loading while maintaining good ion diffusion through optimized electrode tortuosity.However,conventional thick electrodes increase ion diffusion length and cause larger ion concentration gradients,limiting reaction kinetics.We demonstrate a strategy for building interpenetrated structures that shortens ion diffusion length and reduces ion concentration inhomogeneity.This free-standing device structure also avoids short-circuiting without needing a separator.The feature size and number of interpenetrated units can be adjusted during printing to balance surface area and ion diffusion.Starting with a 3D-printed interpenetrated polymer substrate,we metallize it to make it conductive.This substrate has two individually addressable electrodes,allowing selective electrodeposition of energy storage materials.Using a Zn//MnO_(2) battery as a model system,the interpenetrated device outperforms conventional separate electrode configurations,improving volumetric energy density by 221%and exhibiting a higher capacity retention rate of 49%compared to 35%at temperatures from 20 to 0℃.Our study introduces a new EESD architecture applicable to Li-ion,Na-ion batteries,supercapacitors,etc.
基金the National Natural Science Foundation of China(U21A20172,21975028)the China Postdoctoral Science Foundation under Grant Number 2023 M740167.
文摘Enhancing the lifetime of perovskite solar cells(PSCs)is one of the essential challenges for their industrialization.Although the external encapsulation protects the perovskite device from the erosion of moisture and oxygen under various harsh conditions.However,the perovskite devices still undergo static and dynamic thermal stress during thermal and thermal cycling aging,respectively,resulting in irreversible damage to the morphology,component,and phase of stacked materials.Herein,the viscoelastic polymer polyvinyl butyral(PVB)material is designed onto the surface of perovskite films to form flexible interface encapsulation.After PVB interface encapsulation,the surface modulus of perovskite films decreases by nearly 50%,and the interface stress range under the dynamic temperature field(−40 to 85°C)drops from−42.5 to 64.8 MPa to−14.8 to 5.0 MPa.Besides,PVB forms chemical interactions with FA+cations and Pb^(2+),and the macroscopic residual stress is regulated and defects are reduced of the PVB encapsulated perovskite film.As a result,the optimized device's efficiency increases from 22.21%to 23.11%.Additionally,after 1500 h of thermal treatment(85°C),1000 h of damp heat test(85°C&85%RH),and 250 cycles of thermal cycling test(−40 to 85°C),the devices maintain 92.6%,85.8%,and 96.1%of their initial efficiencies,respectively.
基金funding support from the National Natural Science Foundation of China (52172182, 21975028, 22011540377, 22005035, U21A20172)。
文摘Perovskite solar cell has gained widespread attention as a promising technology for renewable energy.However, their commercial viability has been hampered by their long-term stability and potential Pb leakage. Herein, we demonstrate a bifunctional passivator of the potassium tartrate(PT) to address both challenges. PT minimizes the Pb leakage in perovskites and also heals cationic vacancy defects, resulting in improved device performance and stability. Benefiting from PT modification, the power conversion efficiency(PCE) is improved to 23.26% and the Pb leakage in unencapsulated films is significantly reduced to 9.79 ppm. Furthermore, the corresponding device exhibits no significant decay in PCE after tracking at the maximum power point(MPP) for 2000 h under illumination(LED source, 100 mW cm^(-2)).
基金Supported by the National Key Research and Development Program of China,No.2018YFA0208902National Science Foundation of China,No.82272632,No.81672318,and No.U1604281+1 种基金Beijing Science Foundation of China,No.7171008Youth Innovation Science Foundation of Chinese PLA General Hospital,No.22QNCZ027.
文摘BACKGROUND Targeting DNA damage response(DDR)pathway is a cutting-edge strategy.It has been reported that Schlafen-11(SLFN11)contributes to increase chemosensitivity by participating in DDR.However,the detailed mechanism is unclear.AIM To investigate the role of SLFN11 in DDR and the application of synthetic lethal in esophageal cancer with SLFN11 defects.METHODS To reach the purpose,eight esophageal squamous carcinoma cell lines,142 esophageal dysplasia(ED)and 1007 primary esophageal squamous cell carcinoma(ESCC)samples and various techniques were utilized,including methylationspecific polymerase chain reaction,CRISPR/Cas9 technique,Western blot,colony formation assay,and xenograft mouse model.RESULTS Methylation of SLFN11 was exhibited in 9.15%of(13/142)ED and 25.62%of primary(258/1007)ESCC cases,and its expression was regulated by promoter region methylation.SLFN11 methylation was significantly associated with tumor differentiation and tumor size(both P<0.05).However,no significant associations were observed between promoter region methylation and age,gender,smoking,alcohol consumption,TNM stage,or lymph node metastasis.Utilizing DNA damaged model induced by low dose cisplatin,SLFN11 was found to activate non-homologous end-joining and ATR/CHK1 signaling pathways,while inhibiting the ATM/CHK2 signaling pathway.Epigenetic silencing of SLFN11 was found to sensitize the ESCC cells to ATM inhibitor(AZD0156),both in vitro and in vivo.CONCLUSION SLFN11 is frequently methylated in human ESCC.Methylation of SLFN11 is sensitive marker of ATM inhibitor in ESCC.
基金Y.Li acknowledges the financial support from the National Natural Science Foundation of China(No.52171199)X.Ke acknowledges the financial support from the National Natural Science Foundation of China(No.12074017).
文摘The performance of proton exchange membrane fuel cells is heavily dependent on the microstructure of electrode catalyst especially at low catalyst loadings.This work shows a hybrid electrocatalyst consisting of PtNi-W alloy nanocrystals loaded on carbon surface with atomically dispersed W sites by a two-step straightforward method.Single-atomic W can be found on the carbon surface,which can form protonic acid sites and establish an extended proton transport network at the catalyst surface.When implemented in membrane electrode assembly as cathode at ultra-low loading of 0.05 mgPt cm^(−2),the peak power density of the cell is enhanced by 64.4%compared to that with the commercial Pt/C catalyst.The theoretical calculation suggests that the single-atomic W possesses a favorable energetics toward the formation of*OOH whereby the intermediates can be efficiently converted and further reduced to water,revealing a interfacial cascade catalysis facilitated by the single-atomic W.This work highlights a novel functional hybrid electrocatalyst design from the atomic level that enables to solve the bottle-neck issues at device level.
基金supported by the National Natural Science Foundation of China (21975028, U21A20172 and 22011540377)the Special Key Projects (2022-JCJQ-ZD-224-12)。
文摘To achieve high power conversion efficiency(PCE) and long-term stability of perovskite solar cells(PSCs), a hole transport layer(HTL) with persistently high conductivity, good moisture/oxygen barrier ability, and adequate passivation capability is important. To achieve enough conductivity and effective hole extraction, spiro-OMe TAD, one of the most frequently used HTL in optoelectronic devices, often needs chemical doping with a lithium compound(LiTFSI). However, the lithium salt dopant induces crystallization and has a negative impact on the performance and lifetime of the device due to its hygroscopic nature. Here, we provide an easy method for creating a gel by mixing a natural small molecule additive(thioctic acid, TA) with spiro-OMe TAD. We discover that gelation effectively improves the compactness of resultant HTL and prevents moisture and oxygen infiltration. Moreover, the gelation of HTL improves not only the conductivity of spiro-OMe TAD, but also the operational robustness of the devices in the atmospheric environment. In addition, TA passivates the perovskite defects and facilitates the charge transfer from the perovskite layer to HTL. As a consequence, the optimized PSCs based on the gelated HTL exhibit an improved PCE(22.52%) with excellent device stability.
基金funding support from the National Natural Science Foundation of China(U21A20172,21975028,22005035)the Beijing Natural Science Foundation(JQ19008)the China Postdoctoral Science Foundation(2020M670144,2020M680012,2020TQ0043)。
文摘Flexible perovskite solar cells have attracted widespread attention due to their unique advantages in lightweight,high flexibility,and easy deformation,which are suitable for portable electronics.However,the inverted(p-i-n)structured devices suffer from poor stability largely due to the low adhesion at the brittle interface(the hole transport layer/perovskite).Herein,zeolitic imidazolate framework-67(ZIF-67)is applied to inverted structured cells to optimize the interface and prolong the device lifetime.As a result,the flexible devices based on ZIF-67 obtain the champion power conversion efficiency of 20.16%.Over 1000 h under continuous light irradiation,the device retains 96%and 80%of its original efficiency without and with bias,respectively.Notably,devices show mechanical endurance with over 78%efficiency retention after 10,000 cycles of consecutive bending cycles(R=6 mm).The introduction of ZIF-67 suppresses the cracking in device bending,which results in improved environmental stability and bending durability.
文摘In the field of speech bandwidth exten-sion,it is difficult to achieve high speech quality based on the shallow statistical model method.Although the application of deep learning has greatly improved the extended speech quality,the high model complex-ity makes it infeasible to run on the client.In order to tackle these issues,this paper proposes an end-to-end speech bandwidth extension method based on a temporal convolutional neural network,which greatly reduces the complexity of the model.In addition,a new time-frequency loss function is designed to en-able narrowband speech to acquire a more accurate wideband mapping in the time domain and the fre-quency domain.The experimental results show that the reconstructed wideband speech generated by the proposed method is superior to the traditional heuris-tic rule based approaches and the conventional neu-ral network methods for both subjective and objective evaluation.
基金Supported by 2021 Graduate Education and Teaching Quality Engineering Project(2021yjsjd03)Provincial New Era Education Quality Project in 2022(2022lhpysfjd023,2022cxcyjs010)+2 种基金2020 School-level Teaching Quality Engineering Project of Anhui Agricultural University(2020aujyxm58)Project of Research on Intelligent Agriculture Seminar and Research-based Teaching Model and Practice Research for New Agriculture(2021yjsjy09)Collaborative Innovation Project(22108101)。
文摘Taking the practice status of professional master’s degree candidates for agriculture in Anhui Agricultural University as an example,this paper analyzes the key factors affecting the practical training of graduate students in this major,and puts forward some strategies for improving the practice quality of professional master’s degree candidates.In terms of training professional master’s degree candidates,it is considered that agricultural colleges and universities should start with collaborative education,supervision and assessment mechanism,practice content and form,make full use of a large number of agricultural enterprise resources owned by colleges and universities and a good cooperation foundation in enterprises,so as to achieve the purpose of improving the practice quality of professional master’s degree candidates.
