Breast cancer is the most common malignant tumor in Chinese women.Early screening is the best way to improve the rates of early diagnosis and survival of breast cancer patients.The peak onset age for breast cancer in ...Breast cancer is the most common malignant tumor in Chinese women.Early screening is the best way to improve the rates of early diagnosis and survival of breast cancer patients.The peak onset age for breast cancer in Chinese women is considerably younger than those in European and American women.It is imperative to develop breast cancer screening guideline that is suitable for Chinese women.By summarizing the current evidence on breast cancer screening in Chinese women,and referring to the latest guidelines and consensus on breast cancer screening in Europe,the United States,and East Asia,the China Anti-Cancer Association and National Clinical Research Center for Cancer(Tianjin Medical University Cancer Institute and Hospital)have formulated population-based guideline for breast cancer screening in Chinese women.The guideline provides recommendations on breast cancer screening for Chinese women at average or high risk of breast cancer according to the following three aspects:age of screening,screening methods,and screening interval.This article provides more detailed information to support the recommendations in this guideline and to provide more direction for current breast cancer screening practices in China.展开更多
Despite of suitable band structures for harvesting solar light and driving water redox reactions,polymeric carbon nitride(PCN)has suffered from poor charge transfer ability and sluggish surface reaction kinetics,which...Despite of suitable band structures for harvesting solar light and driving water redox reactions,polymeric carbon nitride(PCN)has suffered from poor charge transfer ability and sluggish surface reaction kinetics,which limit its photocatalytic activity for water splitting.Herein,atomically dispersed Zn-coordinated three-dimensional(3D)sponge-like PCN(Zn-PCN)is synthesized through a novel intermediate coordination strategy.Advanced characterizations and theoretical calculations well evidence that Zn single atoms are coordinated and stabilized on PCN in the form of Zn-N_(6) configura-tion featured with an electron-deficient state.Such an electronic configuration has been demonstrated contributive to promoted electron excitation,accelerated charge separation and transfer as well as reduced water redox barriers.Further benefited from the abundant surface active sites derived from the 3D porous structure,Zn-PCN realizes visible-light photocatalysis for overall water splitting with H_(2) and O_(2) simultaneously evolved at a stoichiometric ratio of 2:1.This work brings new insights into the design of novel single-atom photocatalysts by deepening the understanding of electronic configurations and reactive sites favorable to excellent photocatalysis for water splitting and related solar energy conversion reactions.展开更多
Development of a low-cost and durable bifunctional electrocatalyst with high catalytic activity by hybridizing rare earth metal and non-noble metal is of utmost significance.Herein,a bifunctional electrocatalyst consi...Development of a low-cost and durable bifunctional electrocatalyst with high catalytic activity by hybridizing rare earth metal and non-noble metal is of utmost significance.Herein,a bifunctional electrocatalyst consisting of MoO_(2)and CeO_(x)heterostructure is synthesized via interfacial engineering.Particularly,due to its unique hetero-interface with abundant oxygen vacancies,the MoO_(2)-CeO_(x)_(x)/NF is able to exhibit outstanding hydrogen evolution reaction(HER) performance with an overpotential of 26 mV at 10 mA cm^(-2),and a preferable oxygen evolution reaction(OER) overpotential of 272 mV at 100 mA cmin 1 M KOH.The recorded HER and OER overpotentials of MoO_(2)-CeO_(x)/NF are clearly smaller than those of Pt/C(HER overpotential of 27 mV) and RuO(OER overpotential of 393 mV) at the same current density.More importantly,MoO_(2)-CeO_(x)/NF can also exhibit good HER activity with an overpotential of 50 mV at 10 mA cmin acidic media.Thus,it is expected that this work can offer a new approach in the realization of high-catalytic alkaline overall water splitting and acidic HER performance through the rational design of rare-earth metal and non-noble metal heterostructure.展开更多
The cobalt-free Mn-based Li-rich layered oxide material has the advantages of low cost,high energy density,and good performance at low temperatures,and is the promising choice for energy storage batteries.However,the ...The cobalt-free Mn-based Li-rich layered oxide material has the advantages of low cost,high energy density,and good performance at low temperatures,and is the promising choice for energy storage batteries.However,the long-cycling stability of batteries needs to be improved.Herein,the Mn-based Li-rich cathode materials with small amounts of Li2 MnO3 crystal domains and gradient doping of Al and Ti elements from the surface to the bulk have been developed to improve the structure and interface stability.Then the batteries with a high energy density of 600 Wh kg^(-1),excellent capacity retention of 99.7%with low voltage decay of 0.03 mV cycle^(-1) after 800 cycles,and good rates performances can be achieved.Therefore,the structure and cycling stability of low voltage Mn-based Li-rich cathode materials can be significantly improved by the bulk structure design and interface regulation,and this work has paved the way for developing low-cost and high-energy Mn-based energy storage batteries with long lifetime.展开更多
Precipitation at grain boundaries is typically not regarded as an efficient method for strengthening materials since it can induce grain boundary embrittlement, which detrimentally affects ductility. In this research,...Precipitation at grain boundaries is typically not regarded as an efficient method for strengthening materials since it can induce grain boundary embrittlement, which detrimentally affects ductility. In this research, we developed a multi-principal element alloy (MPEA) with the composition Cr_(30)Co_(30)Ni_(30)Al_(5)Ti_(5) (at.%), incorporating both intragranular and intergranular nanoprecipitates. Utilizing multiscale, three-dimensional, and in-situ electron microscopy techniques, coupled with computational simulations, we established that intergranular nanoprecipitation in this material plays a crucial role in enhancing strength and promoting dislocation plasticity. The structure of intergranular nanoprecipitation comprises multiple phases with varying composition and structure. Despite the diversity, the crystal planes conducive to the easy glide of dislocations are well-matched, allowing for the sustained continuity of dislocation slipping across different phase structures. Simultaneously, this structure generates an undulated stress field near grain boundaries, amplifying the strengthening effect and facilitating multiple slip and cross-slip during deformation. Consequently, it promotes the proliferation and storage of dislocations. As a result, our material exhibits a yield strength of approximately 1010 MPa and an ultimate tensile strength of around 1500 MPa, accompanied by a significant fracture elongation of 41 %. Our findings illuminate the potential for harnessing intergranular nanoprecipitation to optimize the strength-ductility trade-off in MPEAs, emphasizing the strategy of leveraging complex compositions for the design of sophisticated functional microstructures.展开更多
Topochemical fluorination introduces significant structural distortions and emerging properties in perovskite oxides via substituting oxygen with fluorine.However,the rapid fluorination process and the similarity betw...Topochemical fluorination introduces significant structural distortions and emerging properties in perovskite oxides via substituting oxygen with fluorine.However,the rapid fluorination process and the similarity between F and O render the O/F site occupation and local lattice evolution during fluorination unclear.Here we investigated the atomic-scale O/F exchange in La2CoO4and quantified the lattice distortion of three ordered structures:La_(2)CoO_(3.5)F,La_(2)CoO_(3)F_(2),and La_(2)CoO_(2.5)F_(3)by utilizing aberration-corrected electron microscopy.Atomic-resolved elemental mapping provides direct evidence for the O/F occupancy in interstitial and apical sites.We revealed that apical F ions induce significant octahedral tilting from 178°to 165°,linearly proportional to the occupancy rate;and cause the obvious change in the fine structure O K edge,meanwhile apical O is exchanged into interstitial sites.The strong octahedral tilt leads to the in-plane elongation of the[CoO_(4)F_(2)]octahedra.These findings elucidate the atomic-scale mechanisms of the entire fluorination process and highlight the significant role of F in tuning the octahedral tilt of functional oxides.展开更多
Leukoaraiosis(LA)results from ischemic injury in small cerebral vessels,which may be attributable to decreased vascular density,reduced cerebrovascular angiogenesis,decreased cerebral blood flow,or microcirculatory dy...Leukoaraiosis(LA)results from ischemic injury in small cerebral vessels,which may be attributable to decreased vascular density,reduced cerebrovascular angiogenesis,decreased cerebral blood flow,or microcirculatory dysfunction in the brain.In this study,we enrolled 357 patients with mild intracerebral hemorrhage(ICH)from five hospitals in China and analyzed the relationships between LA and clinical symptom severity at admission,neurological function prognosis at 3 months,and 1-year stroke recurrence.Patients were divided into groups based on Fazekas scale scores:no LA(n=83),mild LA(n=64),moderate LA(n=98)and severe LA(n=112).More severe LA,larger hematoma volume,and higher blood glucose level at admission were associated with more severe neurological deficit.More severe LA,older age and larger hematoma volume were associated with worse neurological function prognosis at 3 months.In addition,moderate-to-severe LA,admission glucose and symptom-free cerebral infarction were associated with 1-year stroke recurrence.These findings suggest that LA severity may be a potential marker of individual ICH vulnerability,which can be characterized by poor tolerance to intracerebral attack or poor recovery ability after ICH.Evaluating LA severity in patients with mild ICH may help neurologists to optimize treatment protocols.This study was approved by the Ethics Committee of Ruijin Hospital Affiliated to Shanghai Jiao Tong University(approval No.12)on March 10,2011.展开更多
In this study,complete tetracycline(TTC)and above 50%of total organic carbon(TOC)were removed by Fe S/PS after 30 min under optimized conditions.Although free radicals and high-valent iron ions were identified to gene...In this study,complete tetracycline(TTC)and above 50%of total organic carbon(TOC)were removed by Fe S/PS after 30 min under optimized conditions.Although free radicals and high-valent iron ions were identified to generate in the process,the apparent similarity between intermediate products of Fe S/PS,Fe/PS,and UV/PS systems demonstrated that the degradation of TTC was due to sulfate radicals(SO_(4)·^(-))and hydroxyl radicals(·OH).Based on the reaction between free radicals and organic matter,we speculated that TTC in the Fe S/PS system was decomposed and mineralized by dehydration,dehydrogenation,hydroxyl addition,demethylation,substitution,E-transfer,and ring-opening.Furthermore,a new understanding of Fe S-mediated PS activation based on stoichiometry and kinetic analysis showed that there were both homogeneous and heterogeneous reactions that occurred in the entire progress.However,due to the effect of p H on the dissolution of iron ions,the homogeneous reaction became the principal process with iron ions concentration exceeding 1.35 mg/L.This work provides a theoretical basis for the study of the degradation of TTC-containing wastewater by the iron-based advanced oxidation process.展开更多
LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)layered oxides have been regarded as promising alternative cathodes for the next generation of high-energy lithium ion batteries(LIBs)due to high discharge capacities and energy ...LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)layered oxides have been regarded as promising alternative cathodes for the next generation of high-energy lithium ion batteries(LIBs)due to high discharge capacities and energy densities at high operation voltage.However,the capacity fading under high operation voltage still restricts the practical application.Herein,the capacity degradation mechanism of NCM811 at atomic-scale is studied in detail under various cut-off voltages using aberration-corrected scanning transmission electron microscopy(STEM).It is observed that the crystal structure of NCM811 evolution from a layered structure to a rock-salt phase is directly accompanied by serious intergranular cracks under 4.9 V,which is distinguished from the generally accepted structure evolution of layered,disordered layered,defect rock salt and rock salt phases,also observed under 4.3 and 4.7 V.The electron energy loss spectroscopy analysis also confirms the reduction of Ni and Co from the surface to the bulk,not the previously reported only Li/Ni interlayer mixing.The degradation mechanism of NCM811 at a high cut-off voltage of4.9 V is attributed to the formation of intergranular cracks induced by defects,the direct formation of the rock salt phase,and the accompanied reduction of Ni^(2+)and Co^(2+)phases from the surface to the bulk.展开更多
Objective:This post-approval safety study assessed the efficacy and safety of exemestane after 2-3 years of tamoxifen treatment among postmenopausal women with estrogen receptor-positive(ER+)early breast cancer in Chi...Objective:This post-approval safety study assessed the efficacy and safety of exemestane after 2-3 years of tamoxifen treatment among postmenopausal women with estrogen receptor-positive(ER+)early breast cancer in China.Methods:Enrolled patients had received 2-3 years of tamoxifen and were then switched to exemestane for completion of 5 consecutive years of adjuvant endocrine therapy.The primary endpoint was the time from enrollment to the first occurrence of locoregional/distant recurrence of the primary breast cancer,appearance of a second primary or contralateral breast cancer,or death due to any cause.Other endpoints included the proportion of patients experiencing each event,incidence rate per annum,relationships between human epidermal growth factor receptor 2 status and time to event,and relationship between disease history variables and time to event.Results:Overall,558 patients were included in the full analysis set:397(71.1%)completed the study,20experienced an event,and 141 discontinued[47 owing to an adverse event(AE);37 no longer willing to participate].Median duration of treatment was 29.5(range,0.1-57.7)months.Median time to event was not reached.Eventfree survival probability at 36 months was 91.4%(95%CI,87.7%-95.1%).The event incidence over the total exposure time of exemestane therapy was 3.5 events/100 person-years(20/565).Multivariate analysis showed an association between tumor,lymph node,and metastasis stage at initial diagnosis and time to event[hazard ratio:1.532(95%CI,1.129-2.080);P=0.006].Most AEs were grade 1 or 2 in severity,with arthralgia(7.7%)being the most common treatment-related AE.Conclusions:This study supports the efficacy and safety of exemestane in postmenopausal Chinese women with ER+breast cancer previously treated with adjuvant tamoxifen for 2-3 years.No new safety signals were identified in the Chinese population.展开更多
Compared with female breast cancer, male breast cancer is a rare disease, and the relationship between clinical/pathologic features and prognosis is controversial, or even largely unknown. In this study, we performed ...Compared with female breast cancer, male breast cancer is a rare disease, and the relationship between clinical/pathologic features and prognosis is controversial, or even largely unknown. In this study, we performed a retrospective analysis using clinical and pathologic data from 109 nonmetastatic operable male breast cancer patients treated from January 1996 to December 2011 at Tianjin Medical University Cancer Institute and Hospital. Log-rank test showed that lower tumor stage, no lymph node involvement, and positive estrogen/progesterone receptor status were good predictors of both disease-free survival and overall survival on univariate analysis. However, hormonotherapy is only a good predictive factor of disease-free survival, and not of overall survival. In addition, based on a Cox proportional hazard regression model, only lymph node involvement, and estrogen/progesterone receptor status were statistically significant predictive factors on multivariate analysis. Our results demonstrated that although adjuvant systemic therapy is used extensively in male breast cancer patients and prognosis has improved over the last few decades, lymph node involvement, and estrogen/progesterone receptor status are still the most important prognostic factors. A prospective multi-center study with a larger sample size is urgently needed to further understand male breast cancer.展开更多
The notorious growth of zinc dendrite and the water-induced corrosion of zinc metal anodes(ZMAs)restrict the practical development of aqueous zinc ion batteries(AZIBs).In this work,a zinc metallized,imide-pillared cov...The notorious growth of zinc dendrite and the water-induced corrosion of zinc metal anodes(ZMAs)restrict the practical development of aqueous zinc ion batteries(AZIBs).In this work,a zinc metallized,imide-pillared covalent organic framework(ZPC)protective film has been engineered as a stable Zn^(2+)ion-conducting interphase to modulate interfacial kinetics and suppress side reactions for ZMAs.Compared to bare Zn,ZPC@Zn exhibits a higher Zn^(2+)ionic conductivity,a larger Zn^(2+)transference number,a lower electronic conductivity,a smaller desolvation activation energy and correspondingly a significant suppression of corrosion,hydrogen evolution and Zn dendrites.Impressively,the ZPC@Zn||ZPC@Zn symmetric cell obtains a cycling lifespan over 3000 h under 5 mA cm^(-2)for 1 mA h cm^(-2).The ZPC@Zn||NH_(4)V_(4)O_(10)coin-type full battery delivers a specific capacity of 195.8 mA h g^(-1)with a retention rate of78.5%at 2 A g^(-1)after 1100 cycles,and the ZPC@Zn||NH_(4)V_(4)O_(10) pouch full cell shows a retention of70.1%in reversible capacity at 3 A g^(-1)after 1100 cycles.The present incorporation of imide-linked covalent organic frameworks in the surface modification of ZMAs will offer fresh perspectives in the search for ideal protective films for the practicality of AZIBs.展开更多
Understanding the structural origin of the competition between oxygen 2p and transition-metal 3d orbitals in oxygen-redox(OR)layered oxides is eminently desirable for exploring reversible and high-energy-density Li/Na...Understanding the structural origin of the competition between oxygen 2p and transition-metal 3d orbitals in oxygen-redox(OR)layered oxides is eminently desirable for exploring reversible and high-energy-density Li/Na-ion cathodes.Here,we reveal the correlation between cationic ordering transition and OR degradation in ribbon-ordered P3-Na_(0.6)Li_(0.2)Mn_(0.8)O_(2) via in situ structural analysis.Comparing two different voltage windows,the OR capacity can be improved approximately twofold when suppressing the in-plane cationic ordering transition.We find that the intralayer cationic migration is promoted by electrochemical reduction from Mn^(4+)to Jahn–Teller Mn^(3+)and the concomitant NaO_(6) stacking transformation from triangular prisms to octahedra,resulting in the loss of ribbon ordering and electrochemical decay.First-principles calculations reveal that Mn^(4+)/Mn^(3+)charge ordering and alignment of the degenerate eg orbital induce lattice-level collective Jahn–Teller distortion,which favors intralayer Mn-ion migration and thereby accelerates OR degradation.These findings unravel the relationship between in-plane cationic ordering and OR reversibility and highlight the importance of superstructure protection for the rational design of reversible OR-active layered oxide cathodes.展开更多
Rhodium(Rh)-based catalysts have shown superior potential over platinum for the alkaline electrocatalytic hydrogen evolution reaction(HER).However,achieving high catalytic activity while minimizing Rh usage remains a ...Rhodium(Rh)-based catalysts have shown superior potential over platinum for the alkaline electrocatalytic hydrogen evolution reaction(HER).However,achieving high catalytic activity while minimizing Rh usage remains a significant challenge.Herein,we anchored 1.48 wt.%Rh clusters onto nickel-iron layered double hydroxides with cationic defects.The Rh clusters exhibit multiple highly reactive crystallographic facets,providing numerous active sites for catalytic reactions.The cationic vacancies facilitate efficient charge transfer between the Rh clusters and the support through Rh-O bonds,lowering the d-band center of Rh and optimizing hydrogen adsorption strength.Consequently,the synthesized catalyst demonstrates exceptional performance,achieving an ultra-low overpotential of 4 mV at 10 mA·cm^(−2),surpassing all previously reported Rh-based catalysts.This work presents a promising strategy for designing cost-effective and highly efficient alkaline HER catalysts.展开更多
基金supported by National Key Technology Support Program (Grant No. 2015BAI12B15)
文摘Breast cancer is the most common malignant tumor in Chinese women.Early screening is the best way to improve the rates of early diagnosis and survival of breast cancer patients.The peak onset age for breast cancer in Chinese women is considerably younger than those in European and American women.It is imperative to develop breast cancer screening guideline that is suitable for Chinese women.By summarizing the current evidence on breast cancer screening in Chinese women,and referring to the latest guidelines and consensus on breast cancer screening in Europe,the United States,and East Asia,the China Anti-Cancer Association and National Clinical Research Center for Cancer(Tianjin Medical University Cancer Institute and Hospital)have formulated population-based guideline for breast cancer screening in Chinese women.The guideline provides recommendations on breast cancer screening for Chinese women at average or high risk of breast cancer according to the following three aspects:age of screening,screening methods,and screening interval.This article provides more detailed information to support the recommendations in this guideline and to provide more direction for current breast cancer screening practices in China.
基金This work was supported by the National Key Research and Development Program of China(2018YFB1502003)the National Natural Science Foundation of China(52225606,21875183,52172248)+2 种基金the“Fundamental Research Funds for the Central Universities”the Natural Science Basic Research Program of Shaanxi Province(2019JCW-10)“The Youth Innovation Team of Shaanxi Universities”.
文摘Despite of suitable band structures for harvesting solar light and driving water redox reactions,polymeric carbon nitride(PCN)has suffered from poor charge transfer ability and sluggish surface reaction kinetics,which limit its photocatalytic activity for water splitting.Herein,atomically dispersed Zn-coordinated three-dimensional(3D)sponge-like PCN(Zn-PCN)is synthesized through a novel intermediate coordination strategy.Advanced characterizations and theoretical calculations well evidence that Zn single atoms are coordinated and stabilized on PCN in the form of Zn-N_(6) configura-tion featured with an electron-deficient state.Such an electronic configuration has been demonstrated contributive to promoted electron excitation,accelerated charge separation and transfer as well as reduced water redox barriers.Further benefited from the abundant surface active sites derived from the 3D porous structure,Zn-PCN realizes visible-light photocatalysis for overall water splitting with H_(2) and O_(2) simultaneously evolved at a stoichiometric ratio of 2:1.This work brings new insights into the design of novel single-atom photocatalysts by deepening the understanding of electronic configurations and reactive sites favorable to excellent photocatalysis for water splitting and related solar energy conversion reactions.
基金financially supported by the National Natural Science Foundation of China (No. 22065015)Key Research Program of Jiangxi Province of China (No. 20202BBEL53023)。
文摘Development of a low-cost and durable bifunctional electrocatalyst with high catalytic activity by hybridizing rare earth metal and non-noble metal is of utmost significance.Herein,a bifunctional electrocatalyst consisting of MoO_(2)and CeO_(x)heterostructure is synthesized via interfacial engineering.Particularly,due to its unique hetero-interface with abundant oxygen vacancies,the MoO_(2)-CeO_(x)_(x)/NF is able to exhibit outstanding hydrogen evolution reaction(HER) performance with an overpotential of 26 mV at 10 mA cm^(-2),and a preferable oxygen evolution reaction(OER) overpotential of 272 mV at 100 mA cmin 1 M KOH.The recorded HER and OER overpotentials of MoO_(2)-CeO_(x)/NF are clearly smaller than those of Pt/C(HER overpotential of 27 mV) and RuO(OER overpotential of 393 mV) at the same current density.More importantly,MoO_(2)-CeO_(x)/NF can also exhibit good HER activity with an overpotential of 50 mV at 10 mA cmin acidic media.Thus,it is expected that this work can offer a new approach in the realization of high-catalytic alkaline overall water splitting and acidic HER performance through the rational design of rare-earth metal and non-noble metal heterostructure.
基金supported by the National Key R&D Program of China(No.2022YFB2404400)the National Natural Science Foundation of China(Nos.U23A20577,52372168,92263206 and 21975006)+1 种基金the“The Youth Beijing Scholars program”(No.PXM2021_014204_000023)the Beijing Natural Science Foundation(Nos.2222001 and KM202110005009).
文摘The cobalt-free Mn-based Li-rich layered oxide material has the advantages of low cost,high energy density,and good performance at low temperatures,and is the promising choice for energy storage batteries.However,the long-cycling stability of batteries needs to be improved.Herein,the Mn-based Li-rich cathode materials with small amounts of Li2 MnO3 crystal domains and gradient doping of Al and Ti elements from the surface to the bulk have been developed to improve the structure and interface stability.Then the batteries with a high energy density of 600 Wh kg^(-1),excellent capacity retention of 99.7%with low voltage decay of 0.03 mV cycle^(-1) after 800 cycles,and good rates performances can be achieved.Therefore,the structure and cycling stability of low voltage Mn-based Li-rich cathode materials can be significantly improved by the bulk structure design and interface regulation,and this work has paved the way for developing low-cost and high-energy Mn-based energy storage batteries with long lifetime.
基金supported by the National Science Fund for Distinguished Young Scholars of China(No.52325102)the Natural Science Foundation of Zhejiang Province,China(No.LZ22E010001)the National Key R&D Program of China(No.2023YFB2405802).
文摘Precipitation at grain boundaries is typically not regarded as an efficient method for strengthening materials since it can induce grain boundary embrittlement, which detrimentally affects ductility. In this research, we developed a multi-principal element alloy (MPEA) with the composition Cr_(30)Co_(30)Ni_(30)Al_(5)Ti_(5) (at.%), incorporating both intragranular and intergranular nanoprecipitates. Utilizing multiscale, three-dimensional, and in-situ electron microscopy techniques, coupled with computational simulations, we established that intergranular nanoprecipitation in this material plays a crucial role in enhancing strength and promoting dislocation plasticity. The structure of intergranular nanoprecipitation comprises multiple phases with varying composition and structure. Despite the diversity, the crystal planes conducive to the easy glide of dislocations are well-matched, allowing for the sustained continuity of dislocation slipping across different phase structures. Simultaneously, this structure generates an undulated stress field near grain boundaries, amplifying the strengthening effect and facilitating multiple slip and cross-slip during deformation. Consequently, it promotes the proliferation and storage of dislocations. As a result, our material exhibits a yield strength of approximately 1010 MPa and an ultimate tensile strength of around 1500 MPa, accompanied by a significant fracture elongation of 41 %. Our findings illuminate the potential for harnessing intergranular nanoprecipitation to optimize the strength-ductility trade-off in MPEAs, emphasizing the strategy of leveraging complex compositions for the design of sophisticated functional microstructures.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.52322212,52025025,5225040212474001)the National Key R&D Program of China(Grant Nos.2022YFA1403203 and 2023YFA1406300)。
文摘Topochemical fluorination introduces significant structural distortions and emerging properties in perovskite oxides via substituting oxygen with fluorine.However,the rapid fluorination process and the similarity between F and O render the O/F site occupation and local lattice evolution during fluorination unclear.Here we investigated the atomic-scale O/F exchange in La2CoO4and quantified the lattice distortion of three ordered structures:La_(2)CoO_(3.5)F,La_(2)CoO_(3)F_(2),and La_(2)CoO_(2.5)F_(3)by utilizing aberration-corrected electron microscopy.Atomic-resolved elemental mapping provides direct evidence for the O/F occupancy in interstitial and apical sites.We revealed that apical F ions induce significant octahedral tilting from 178°to 165°,linearly proportional to the occupancy rate;and cause the obvious change in the fine structure O K edge,meanwhile apical O is exchanged into interstitial sites.The strong octahedral tilt leads to the in-plane elongation of the[CoO_(4)F_(2)]octahedra.These findings elucidate the atomic-scale mechanisms of the entire fluorination process and highlight the significant role of F in tuning the octahedral tilt of functional oxides.
基金supported by the National Natural Science Foundation of China,Nos.81771281(to FXS),81471177(to FXS)the Natural Science Foundation of Shanghai of China,No.20ZR1434200(to YF)。
文摘Leukoaraiosis(LA)results from ischemic injury in small cerebral vessels,which may be attributable to decreased vascular density,reduced cerebrovascular angiogenesis,decreased cerebral blood flow,or microcirculatory dysfunction in the brain.In this study,we enrolled 357 patients with mild intracerebral hemorrhage(ICH)from five hospitals in China and analyzed the relationships between LA and clinical symptom severity at admission,neurological function prognosis at 3 months,and 1-year stroke recurrence.Patients were divided into groups based on Fazekas scale scores:no LA(n=83),mild LA(n=64),moderate LA(n=98)and severe LA(n=112).More severe LA,larger hematoma volume,and higher blood glucose level at admission were associated with more severe neurological deficit.More severe LA,older age and larger hematoma volume were associated with worse neurological function prognosis at 3 months.In addition,moderate-to-severe LA,admission glucose and symptom-free cerebral infarction were associated with 1-year stroke recurrence.These findings suggest that LA severity may be a potential marker of individual ICH vulnerability,which can be characterized by poor tolerance to intracerebral attack or poor recovery ability after ICH.Evaluating LA severity in patients with mild ICH may help neurologists to optimize treatment protocols.This study was approved by the Ethics Committee of Ruijin Hospital Affiliated to Shanghai Jiao Tong University(approval No.12)on March 10,2011.
基金supported by the National Natural Science Foundation of China(No.21876130)Natural Science Foundation of Shanghai(No.18ZR1440800)。
文摘In this study,complete tetracycline(TTC)and above 50%of total organic carbon(TOC)were removed by Fe S/PS after 30 min under optimized conditions.Although free radicals and high-valent iron ions were identified to generate in the process,the apparent similarity between intermediate products of Fe S/PS,Fe/PS,and UV/PS systems demonstrated that the degradation of TTC was due to sulfate radicals(SO_(4)·^(-))and hydroxyl radicals(·OH).Based on the reaction between free radicals and organic matter,we speculated that TTC in the Fe S/PS system was decomposed and mineralized by dehydration,dehydrogenation,hydroxyl addition,demethylation,substitution,E-transfer,and ring-opening.Furthermore,a new understanding of Fe S-mediated PS activation based on stoichiometry and kinetic analysis showed that there were both homogeneous and heterogeneous reactions that occurred in the entire progress.However,due to the effect of p H on the dissolution of iron ions,the homogeneous reaction became the principal process with iron ions concentration exceeding 1.35 mg/L.This work provides a theoretical basis for the study of the degradation of TTC-containing wastewater by the iron-based advanced oxidation process.
基金supported by the National Natural Science Foundation of China(U2032131)the Key R&D Program of Shaanxi Province(2021GY-118)the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(2022SX-TD012 and 2021SXTD012)。
文摘LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)layered oxides have been regarded as promising alternative cathodes for the next generation of high-energy lithium ion batteries(LIBs)due to high discharge capacities and energy densities at high operation voltage.However,the capacity fading under high operation voltage still restricts the practical application.Herein,the capacity degradation mechanism of NCM811 at atomic-scale is studied in detail under various cut-off voltages using aberration-corrected scanning transmission electron microscopy(STEM).It is observed that the crystal structure of NCM811 evolution from a layered structure to a rock-salt phase is directly accompanied by serious intergranular cracks under 4.9 V,which is distinguished from the generally accepted structure evolution of layered,disordered layered,defect rock salt and rock salt phases,also observed under 4.3 and 4.7 V.The electron energy loss spectroscopy analysis also confirms the reduction of Ni and Co from the surface to the bulk,not the previously reported only Li/Ni interlayer mixing.The degradation mechanism of NCM811 at a high cut-off voltage of4.9 V is attributed to the formation of intergranular cracks induced by defects,the direct formation of the rock salt phase,and the accompanied reduction of Ni^(2+)and Co^(2+)phases from the surface to the bulk.
文摘Objective:This post-approval safety study assessed the efficacy and safety of exemestane after 2-3 years of tamoxifen treatment among postmenopausal women with estrogen receptor-positive(ER+)early breast cancer in China.Methods:Enrolled patients had received 2-3 years of tamoxifen and were then switched to exemestane for completion of 5 consecutive years of adjuvant endocrine therapy.The primary endpoint was the time from enrollment to the first occurrence of locoregional/distant recurrence of the primary breast cancer,appearance of a second primary or contralateral breast cancer,or death due to any cause.Other endpoints included the proportion of patients experiencing each event,incidence rate per annum,relationships between human epidermal growth factor receptor 2 status and time to event,and relationship between disease history variables and time to event.Results:Overall,558 patients were included in the full analysis set:397(71.1%)completed the study,20experienced an event,and 141 discontinued[47 owing to an adverse event(AE);37 no longer willing to participate].Median duration of treatment was 29.5(range,0.1-57.7)months.Median time to event was not reached.Eventfree survival probability at 36 months was 91.4%(95%CI,87.7%-95.1%).The event incidence over the total exposure time of exemestane therapy was 3.5 events/100 person-years(20/565).Multivariate analysis showed an association between tumor,lymph node,and metastasis stage at initial diagnosis and time to event[hazard ratio:1.532(95%CI,1.129-2.080);P=0.006].Most AEs were grade 1 or 2 in severity,with arthralgia(7.7%)being the most common treatment-related AE.Conclusions:This study supports the efficacy and safety of exemestane in postmenopausal Chinese women with ER+breast cancer previously treated with adjuvant tamoxifen for 2-3 years.No new safety signals were identified in the Chinese population.
基金ACKNOWLEDGMENTS This study was supported by the National Natural Science Foundation of China （Grants 81472683 and 81202275）, Tianjin Natural Science fund （Grant 13JCQNJC 11000） and Research Seed Foundation of Tianjin Medical University Gancer Hospital and Institute （Grant 1421）.
文摘Compared with female breast cancer, male breast cancer is a rare disease, and the relationship between clinical/pathologic features and prognosis is controversial, or even largely unknown. In this study, we performed a retrospective analysis using clinical and pathologic data from 109 nonmetastatic operable male breast cancer patients treated from January 1996 to December 2011 at Tianjin Medical University Cancer Institute and Hospital. Log-rank test showed that lower tumor stage, no lymph node involvement, and positive estrogen/progesterone receptor status were good predictors of both disease-free survival and overall survival on univariate analysis. However, hormonotherapy is only a good predictive factor of disease-free survival, and not of overall survival. In addition, based on a Cox proportional hazard regression model, only lymph node involvement, and estrogen/progesterone receptor status were statistically significant predictive factors on multivariate analysis. Our results demonstrated that although adjuvant systemic therapy is used extensively in male breast cancer patients and prognosis has improved over the last few decades, lymph node involvement, and estrogen/progesterone receptor status are still the most important prognostic factors. A prospective multi-center study with a larger sample size is urgently needed to further understand male breast cancer.
基金supported by the National Natural Science Foundation of China (52373065)the Joint Fund of Ministry of Education for Equipment Pre-research (8091B032206)+1 种基金the Guang Dong Basic and Applied Basic Research Foundation (2021A1515111067,2023A1515010735)the start-up funding of“Hundred Talent Program”from Sun Yat-sen University。
文摘The notorious growth of zinc dendrite and the water-induced corrosion of zinc metal anodes(ZMAs)restrict the practical development of aqueous zinc ion batteries(AZIBs).In this work,a zinc metallized,imide-pillared covalent organic framework(ZPC)protective film has been engineered as a stable Zn^(2+)ion-conducting interphase to modulate interfacial kinetics and suppress side reactions for ZMAs.Compared to bare Zn,ZPC@Zn exhibits a higher Zn^(2+)ionic conductivity,a larger Zn^(2+)transference number,a lower electronic conductivity,a smaller desolvation activation energy and correspondingly a significant suppression of corrosion,hydrogen evolution and Zn dendrites.Impressively,the ZPC@Zn||ZPC@Zn symmetric cell obtains a cycling lifespan over 3000 h under 5 mA cm^(-2)for 1 mA h cm^(-2).The ZPC@Zn||NH_(4)V_(4)O_(10)coin-type full battery delivers a specific capacity of 195.8 mA h g^(-1)with a retention rate of78.5%at 2 A g^(-1)after 1100 cycles,and the ZPC@Zn||NH_(4)V_(4)O_(10) pouch full cell shows a retention of70.1%in reversible capacity at 3 A g^(-1)after 1100 cycles.The present incorporation of imide-linked covalent organic frameworks in the surface modification of ZMAs will offer fresh perspectives in the search for ideal protective films for the practicality of AZIBs.
基金funding supports from the National Key R&D Program of China(Grant Nos.2022YFB2404400 and 2019YFA0308500)Beijing Natural Science Foundation(Z190010)National Natural Science Foundation of China(Grant Nos.51991344,52025025,52072400,and 52002394)。
文摘Understanding the structural origin of the competition between oxygen 2p and transition-metal 3d orbitals in oxygen-redox(OR)layered oxides is eminently desirable for exploring reversible and high-energy-density Li/Na-ion cathodes.Here,we reveal the correlation between cationic ordering transition and OR degradation in ribbon-ordered P3-Na_(0.6)Li_(0.2)Mn_(0.8)O_(2) via in situ structural analysis.Comparing two different voltage windows,the OR capacity can be improved approximately twofold when suppressing the in-plane cationic ordering transition.We find that the intralayer cationic migration is promoted by electrochemical reduction from Mn^(4+)to Jahn–Teller Mn^(3+)and the concomitant NaO_(6) stacking transformation from triangular prisms to octahedra,resulting in the loss of ribbon ordering and electrochemical decay.First-principles calculations reveal that Mn^(4+)/Mn^(3+)charge ordering and alignment of the degenerate eg orbital induce lattice-level collective Jahn–Teller distortion,which favors intralayer Mn-ion migration and thereby accelerates OR degradation.These findings unravel the relationship between in-plane cationic ordering and OR reversibility and highlight the importance of superstructure protection for the rational design of reversible OR-active layered oxide cathodes.
基金supported by the National Natural Science Foundation of China(Nos.52072255,52271184,and 52250402)Science Fund for Distinguished Young Scholars of Zhejiang Province(No.LR22E020003)+1 种基金Natural Science Foundation of Zhejiang Province(No.LY23E020001)High-level Talents Special Support Program of Taizhou,and Science and Technology Plan Project of Taizhou(No.24gyb14).
文摘Rhodium(Rh)-based catalysts have shown superior potential over platinum for the alkaline electrocatalytic hydrogen evolution reaction(HER).However,achieving high catalytic activity while minimizing Rh usage remains a significant challenge.Herein,we anchored 1.48 wt.%Rh clusters onto nickel-iron layered double hydroxides with cationic defects.The Rh clusters exhibit multiple highly reactive crystallographic facets,providing numerous active sites for catalytic reactions.The cationic vacancies facilitate efficient charge transfer between the Rh clusters and the support through Rh-O bonds,lowering the d-band center of Rh and optimizing hydrogen adsorption strength.Consequently,the synthesized catalyst demonstrates exceptional performance,achieving an ultra-low overpotential of 4 mV at 10 mA·cm^(−2),surpassing all previously reported Rh-based catalysts.This work presents a promising strategy for designing cost-effective and highly efficient alkaline HER catalysts.
