All-solid-state Li batteries(ASSLBs)using solid electrolytes(SEs)have gained significant attention in recent years considering the safety issue and their high energy density.Despite these advantages,the commercializat...All-solid-state Li batteries(ASSLBs)using solid electrolytes(SEs)have gained significant attention in recent years considering the safety issue and their high energy density.Despite these advantages,the commercialization of ASSLBs still faces challenges regarding the electrolyte/electrodes interfaces and growth of Li dendrites.Elemental doping is an effective and direct method to enhance the performance of SEs.Here,we report an Al-F co-doping strategy to improve the overall properties including ion conductivity,high voltage stability,and cathode and anode compatibility.Particularly,the Al-F co-doping enables the formation of a thin Li-Al alloy layer and fluoride interphases,thereby constructing a relatively stable interface and promoting uniform Li deposition.The similar merits of Al-F co-doping are also revealed in the Li-argyrodite series.ASSLBs assembled with these optimized electrolytes gain good electrochemical performance,demonstrating the universality of Al-F co-doping towards advanced SEs.展开更多
本研究拟利用LC-QTOF-MS非靶向代谢组学分析青海枸杞中黄酮代谢路径,阐明青藏高原独特气候因子的调控机制。采集青海3个产地的36份枸杞样本,并记录枸杞转色期(黄变前至黄变后)当地的气候参数(平均光照强度、平均温度、昼夜温差、积温、...本研究拟利用LC-QTOF-MS非靶向代谢组学分析青海枸杞中黄酮代谢路径,阐明青藏高原独特气候因子的调控机制。采集青海3个产地的36份枸杞样本,并记录枸杞转色期(黄变前至黄变后)当地的气候参数(平均光照强度、平均温度、昼夜温差、积温、空气湿度等)。非靶向代谢组学识别出青海枸杞中40种黄酮类和异黄酮类差异代谢物。利用火山图筛选出11个产地特异性差异代谢物,偏最小二乘判别分析枸杞产地的判别准确率为94.44%。京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)通路富集分析揭示黄酮类生物合成代谢途径中差异代谢物的代谢路径。Mental分析揭示平均光照强度和昼夜温差是青海枸杞产地特异性黄酮类物质生物合成的主要调控因子。极端梯度提升模型(eXtreme Gradient Boosting,XGBoost)对青海省枸杞产地的判别准确率达100%。本研究为了解青海枸杞的品质特性提供理论依据。展开更多
Precisely identifying the atomic structure of reducible oxide-supported metal clusters remains challenging yet critical for understanding their catalytic behavior.Herein,we report the preparation of CeO_(2)-supported ...Precisely identifying the atomic structure of reducible oxide-supported metal clusters remains challenging yet critical for understanding their catalytic behavior.Herein,we report the preparation of CeO_(2)-supported bi-layer Pt clusters(Pt_(n)/CeO_(2))via a deposition-reduction strategy,with Pt cluster sizes ranging from 0.8 to 1.2 nm(9–30 atoms).Through combined aberration-corrected high-angle annular dark field scanning transmission electron microscope(HAADF-STEM)imaging,quantitative STEM simulations,and X-ray fine structure(XAFS)analysis,we reveal the bi-layer configuration featuring coordinatively unsaturated Pt^(0) sites on the top layer while maintaining Pt-CeO_(2)interfacial bonding at the bottom.When applied to anti-Markovnikov alkene hydrosilylation,Pt_(n)/CeO_(2)achieves 99.9%silane conversion with a mass-specific activity 2.0×and 8.8×higher than single-atom site(Pt_(1)/CeO_(2))and nanoparticle(Pt_(NP)/CeO_(2))counterparts,respectively.The bi-layer structure endows exceptional cycling stability and anti-leaching properties.This work establishes a multi-scale characterization paradigm to resolve atomic-precision structures of supported clusters,opening avenues for designing robust catalysts with tailored metal-oxide interfaces.展开更多
To investigate the effects of sudden change in wind loads on the running performance of trains on the bridge in crosswinds,a highway-railway one-story bridge was taken as the research object.Aerodynamic coefficients o...To investigate the effects of sudden change in wind loads on the running performance of trains on the bridge in crosswinds,a highway-railway one-story bridge was taken as the research object.Aerodynamic coefficients of the train and the bridge were measured in a series of train-bridge system segment models through wind tunnel tests when two trains passed each other on the bridge and when a train entered and left the wind barrier section of the bridge.Based on the improved SIMPACK and ANSYS rigid-flexible coupling simulation method,a wind-double train-track-bridge system coupled vibration model was established.The dynamic responses of the train were analyzed under the effects of sudden change in wind loads caused by two trains passing each other and a train entering and leaving the wind barrier section of the bridge.The results show that the effects of sudden wind load change caused by the trains passing each other had less effects on the running safety of the leeward-side train than the wind shielding effect caused by the windward-side train in the wind speed range of 10−25 m/s.With the decrease in the porosity of wind barriers,the effects of the sudden wind load change played an increasingly important role in the running safety and comfort of the train.With the increase in wind speed,the lateral response of the train increased obviously because of the effects of sudden wind load change,which affects both the lateral running stability and the comfort of the train.展开更多
Contrast-enhanced computed tomography(CT)contributes to the increasing detection of pancreatic neuroendocrine neoplasms(PNENs).Nevertheless,its value for differentiating pathological tumor grades is not well recognize...Contrast-enhanced computed tomography(CT)contributes to the increasing detection of pancreatic neuroendocrine neoplasms(PNENs).Nevertheless,its value for differentiating pathological tumor grades is not well recognized.In this report,we have conducted a retrospective study on the relationship between the 2017 World Health Organization(WHO)classification and CT imaging features in 94 patients.Most of the investigated features eventually provided statistically significant indicators for discerning PNENs G3 from PNENs G1/G2,including tumor size,shape,margin,heterogeneity,intratumoral blood vessels,vascular invasion,enhancement pattern in both contrast phases,enhancement degree in both phases,tumor-to-pancreas contrast ratio in both phases,common bile duct dilatation,lymph node metastases,and liver metastases.Ill-defined tumor margin was an independent predictor for PNENs G3 with the highest area under the curve(AUC)of 0.906 in the multivariable logistic regression and receiver operating characteristic curve analysis.The portal enhancement ratio(PER)was shown the highest AUC of 0.855 in terms of quantitative features.Our data suggest that the traditional contrastenhanced CT still plays a vital role in differentiation of tumor grades and heterogeneity analysis prior to treatment.展开更多
Biomass-derived residue carbonization has been an important issue for"carbon fixation"and"zero emission",and the carbonized products have multiple application potentials.However,there have been no ...Biomass-derived residue carbonization has been an important issue for"carbon fixation"and"zero emission",and the carbonized products have multiple application potentials.However,there have been no specific research to study the differences in macro-and micro-morphology,electrical properties and many other aspects of the products obtained from carbonization of pure cellulose,pure lignin or their complex,lignocellulose.In this work,lignocellulose with cellulose to lignin mass ratio of 10:1 is obtained using p-toluenesulfonic acid hydrolysis followed by homogenization process at a controlled condition.Then,carbon heterostructure with fibers and sheets(CH-10)are obtained by pyrolysis at 1500℃.Detailed results imply that the fiber-like carbon structure possesses high crystallinity and low defect density,coming from carbonization of the cellulose content in lignocellulose(LC)nanofibers.Correspondingly,the graphite-like carbon sheet with high defect density and low crystallinity comes from carbonization of the lignin content in LCs.Further investigation indicates CH-10 possesses enhanced polarization and moderate impedance matching which makes it an ideal candidate for electromagnetic wave(EMW)absorption.CH-10 exhibits an excellent EMW absorption performance with a minimum RL value of-50.05 dB and a broadest absorption bandwidth of 4.16 GHz at a coating thickness as thin as 1.3 mm.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52172243,52371215)。
文摘All-solid-state Li batteries(ASSLBs)using solid electrolytes(SEs)have gained significant attention in recent years considering the safety issue and their high energy density.Despite these advantages,the commercialization of ASSLBs still faces challenges regarding the electrolyte/electrodes interfaces and growth of Li dendrites.Elemental doping is an effective and direct method to enhance the performance of SEs.Here,we report an Al-F co-doping strategy to improve the overall properties including ion conductivity,high voltage stability,and cathode and anode compatibility.Particularly,the Al-F co-doping enables the formation of a thin Li-Al alloy layer and fluoride interphases,thereby constructing a relatively stable interface and promoting uniform Li deposition.The similar merits of Al-F co-doping are also revealed in the Li-argyrodite series.ASSLBs assembled with these optimized electrolytes gain good electrochemical performance,demonstrating the universality of Al-F co-doping towards advanced SEs.
文摘本研究拟利用LC-QTOF-MS非靶向代谢组学分析青海枸杞中黄酮代谢路径,阐明青藏高原独特气候因子的调控机制。采集青海3个产地的36份枸杞样本,并记录枸杞转色期(黄变前至黄变后)当地的气候参数(平均光照强度、平均温度、昼夜温差、积温、空气湿度等)。非靶向代谢组学识别出青海枸杞中40种黄酮类和异黄酮类差异代谢物。利用火山图筛选出11个产地特异性差异代谢物,偏最小二乘判别分析枸杞产地的判别准确率为94.44%。京都基因与基因组百科全书(Kyoto Encyclopedia of Genes and Genomes,KEGG)通路富集分析揭示黄酮类生物合成代谢途径中差异代谢物的代谢路径。Mental分析揭示平均光照强度和昼夜温差是青海枸杞产地特异性黄酮类物质生物合成的主要调控因子。极端梯度提升模型(eXtreme Gradient Boosting,XGBoost)对青海省枸杞产地的判别准确率达100%。本研究为了解青海枸杞的品质特性提供理论依据。
基金supported by the National Key Research and Development Program of China(2021YFA1500500)the CAS Project for Young Scientists in Basic Research(YSBR-051)+9 种基金the National Science Fund for Distinguished Young Scholars(21925204)the National Natural Science Foundation of China(NSFC)(22302185,22221003,22250007,22361162655)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(2022QNRC001)the Fundamental Research Funds for the Central Universities(WK9990000167)the Collaborative Innovation Program of Hefei Science Center,CAS(2022HSC-CIP004)the Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy(YLU-DNL Fund 2022012)the Natural Science Foundation of Anhui Province(2308085QB53)the State Key Laboratory of Catalysis(2024SKL-A-01)the International Partnership Program of Chinese Academy of Sciences(123GJHZ2022101GC)support from the Tencent Foundation through the XPLORER PRIZE。
文摘Precisely identifying the atomic structure of reducible oxide-supported metal clusters remains challenging yet critical for understanding their catalytic behavior.Herein,we report the preparation of CeO_(2)-supported bi-layer Pt clusters(Pt_(n)/CeO_(2))via a deposition-reduction strategy,with Pt cluster sizes ranging from 0.8 to 1.2 nm(9–30 atoms).Through combined aberration-corrected high-angle annular dark field scanning transmission electron microscope(HAADF-STEM)imaging,quantitative STEM simulations,and X-ray fine structure(XAFS)analysis,we reveal the bi-layer configuration featuring coordinatively unsaturated Pt^(0) sites on the top layer while maintaining Pt-CeO_(2)interfacial bonding at the bottom.When applied to anti-Markovnikov alkene hydrosilylation,Pt_(n)/CeO_(2)achieves 99.9%silane conversion with a mass-specific activity 2.0×and 8.8×higher than single-atom site(Pt_(1)/CeO_(2))and nanoparticle(Pt_(NP)/CeO_(2))counterparts,respectively.The bi-layer structure endows exceptional cycling stability and anti-leaching properties.This work establishes a multi-scale characterization paradigm to resolve atomic-precision structures of supported clusters,opening avenues for designing robust catalysts with tailored metal-oxide interfaces.
基金Projects(51822803,51878080,51778073) supported by the National Natural Science Foundation of ChinaProjects(2020JJ3035,2018JJ3538) supported by the Hunan Provincial Natural Science Foundation of China。
文摘To investigate the effects of sudden change in wind loads on the running performance of trains on the bridge in crosswinds,a highway-railway one-story bridge was taken as the research object.Aerodynamic coefficients of the train and the bridge were measured in a series of train-bridge system segment models through wind tunnel tests when two trains passed each other on the bridge and when a train entered and left the wind barrier section of the bridge.Based on the improved SIMPACK and ANSYS rigid-flexible coupling simulation method,a wind-double train-track-bridge system coupled vibration model was established.The dynamic responses of the train were analyzed under the effects of sudden change in wind loads caused by two trains passing each other and a train entering and leaving the wind barrier section of the bridge.The results show that the effects of sudden wind load change caused by the trains passing each other had less effects on the running safety of the leeward-side train than the wind shielding effect caused by the windward-side train in the wind speed range of 10−25 m/s.With the decrease in the porosity of wind barriers,the effects of the sudden wind load change played an increasingly important role in the running safety and comfort of the train.With the increase in wind speed,the lateral response of the train increased obviously because of the effects of sudden wind load change,which affects both the lateral running stability and the comfort of the train.
基金This study was supported by a grant from the Innovation Capability Development Project of Jiangsu Province(No.BM2015004).
文摘Contrast-enhanced computed tomography(CT)contributes to the increasing detection of pancreatic neuroendocrine neoplasms(PNENs).Nevertheless,its value for differentiating pathological tumor grades is not well recognized.In this report,we have conducted a retrospective study on the relationship between the 2017 World Health Organization(WHO)classification and CT imaging features in 94 patients.Most of the investigated features eventually provided statistically significant indicators for discerning PNENs G3 from PNENs G1/G2,including tumor size,shape,margin,heterogeneity,intratumoral blood vessels,vascular invasion,enhancement pattern in both contrast phases,enhancement degree in both phases,tumor-to-pancreas contrast ratio in both phases,common bile duct dilatation,lymph node metastases,and liver metastases.Ill-defined tumor margin was an independent predictor for PNENs G3 with the highest area under the curve(AUC)of 0.906 in the multivariable logistic regression and receiver operating characteristic curve analysis.The portal enhancement ratio(PER)was shown the highest AUC of 0.855 in terms of quantitative features.Our data suggest that the traditional contrastenhanced CT still plays a vital role in differentiation of tumor grades and heterogeneity analysis prior to treatment.
基金supported by funding from the National Natural Science Foundation of China(31770609,31570552)Jiangsu Agricultural Science and Technology Independent Innovation Fund(CX(20)3041)。
文摘Biomass-derived residue carbonization has been an important issue for"carbon fixation"and"zero emission",and the carbonized products have multiple application potentials.However,there have been no specific research to study the differences in macro-and micro-morphology,electrical properties and many other aspects of the products obtained from carbonization of pure cellulose,pure lignin or their complex,lignocellulose.In this work,lignocellulose with cellulose to lignin mass ratio of 10:1 is obtained using p-toluenesulfonic acid hydrolysis followed by homogenization process at a controlled condition.Then,carbon heterostructure with fibers and sheets(CH-10)are obtained by pyrolysis at 1500℃.Detailed results imply that the fiber-like carbon structure possesses high crystallinity and low defect density,coming from carbonization of the cellulose content in lignocellulose(LC)nanofibers.Correspondingly,the graphite-like carbon sheet with high defect density and low crystallinity comes from carbonization of the lignin content in LCs.Further investigation indicates CH-10 possesses enhanced polarization and moderate impedance matching which makes it an ideal candidate for electromagnetic wave(EMW)absorption.CH-10 exhibits an excellent EMW absorption performance with a minimum RL value of-50.05 dB and a broadest absorption bandwidth of 4.16 GHz at a coating thickness as thin as 1.3 mm.
