new heterocyclic dipeptide with a highly functionalized 1,2-oxazadecaline core,named trichodermamide H(1),and three known analogues,along with three known polyketides,were isolated from the fermentation extract of the...new heterocyclic dipeptide with a highly functionalized 1,2-oxazadecaline core,named trichodermamide H(1),and three known analogues,along with three known polyketides,were isolated from the fermentation extract of the mangrovederived fungus Penicillium janthinellum XLN32122.The structure of 1 was elucidated on the basis of extensive 1D and 2D NMR spectra data analysis,HR-ESI-MS,electronic circular dichroism(ECD)calculations.Trichodermamide B(3)exhibited better inhibitory effect on nitric oxide(NO)production in lipopolysaccharide(LPS)induced RAW 264.7 cells with an IC_(50)value of(13.13±0.005)μmol/L than that of the positive control dexamethasone[IC_(50)=(136.84±1.33)μmol/L].Compound 3 exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus(MRSA)with an IC_(50)value of 12.5μg/mL,while the positive control vancomycin showed an IC_(50)value of 1.563μg/mL.展开更多
Although progress has been made nationally in terms of drinking water coverage,access remains a significant challenge in Togo’s secondary cities,particularly in Noèpéand Kovié.These areas are experienc...Although progress has been made nationally in terms of drinking water coverage,access remains a significant challenge in Togo’s secondary cities,particularly in Noèpéand Kovié.These areas are experiencing rapid urbanization and sustained population growth,which is putting increasing pressure on often dilapidated infrastructure.This study aims to examine the institutional,regulatory and organizational mechanisms that shape water governance in Noèpéand Kovié,to identify the main obstacles and potential pathways towards equitable and sustainable access to drinking water.The research combined a literature review with qualitative fieldwork,including 67 semi-structured interviews and focus groups with institutional actors,municipal authorities and community association.Thematic analysis was used to triangulate institutional discourse,policy documents and community perspectives.The findings reveal that governance is hindered by institutional fragmentation,weak inter-institutional coordination,compounded by centralized governance.Community-based models,although widespread,suffer from lack of professionalization,financial fragility,weak community participation and conflicts interest.Infrastructure deficits,dependence on ad hoc external funding,and limited regulation exacerbate service inequalities.To address these challenges,this study concludes that water governance in secondary cities must be adapted to institutional and regulatory frameworks while taking local specifics into account.Strengthening institutional and community capacities,updating stakeholder mapping,developing participatory governance mechanisms and establishing shared governance mechanisms are essential.Local master plan aligned with urban planning strategies are recommended to anticipate demographic pressures and climate variability.Such reforms would help to ensure sustainable access to drinking water.展开更多
AIM:To investigate the etiology and clinical characteristics of hospitalized secondary glaucoma(SG)patients in northwestern China.METHODS:A cross-sectional study was conducted involving SG patients hospitalized betwee...AIM:To investigate the etiology and clinical characteristics of hospitalized secondary glaucoma(SG)patients in northwestern China.METHODS:A cross-sectional study was conducted involving SG patients hospitalized between July 2024 and January 2025.Clinical data were collected,including medical history,best-corrected visual acuity(BCVA),intraocular pressure(IOP),slit-lamp examination,gonioscopic findings,and fundus examination.Demographic characteristics,etiological factors,and treatment modalities were analyzed.RESULTS:A total of 67 patients(82 eyes)were enrolled,aged 7 to 90y.Males accounted for 54.0%(36/67),and 22.4%(15/67)of patients had bilateral involvement.The predominant etiologies of SG were neovascular glaucoma(NVG;25.4%),traumatic glaucoma(23.9%),uveitic glaucoma(20.9%),and lens-induced glaucoma(14.9%),collectively accounting for 85.1%of all cases.The peak age-specific incidence occurred in the 50-59 years age group(32.8%,22/67),while NVG was prevalent across the 40-79 years age range.IOP of the 82 affected eyes was stratified into five severity tiers:22-29 mm Hg(15 eyes,18.3%),30-39 mm Hg(14 eyes,17.1%),40-49 mm Hg(13 eyes,15.9%),50-59 mm Hg(20 eyes,24.4%),and≥60 mm Hg(20 eyes,24.4%).The overall mean IOP was 45.2±12.3 mm Hg,indicating a significant pathological elevation.Surgical intervention was required in 46.3%of cases,predominantly for NVG,lensinduced glaucoma,and traumatic glaucoma—conditions prone to rapid IOP elevation.The etiologies with the highest surgical intervention rates were malignant glaucoma,pigmentary glaucoma,lens-induced glaucoma,and NVG.In contrast,uveitic glaucoma cases were primarily managed with targeted anti-inflammatory therapy,which effectively controlled IOP in the early disease stages and potentially obviated the need for surgery.CONCLUSION:This study identifies NVG,traumatic glaucoma,uveitic glaucoma,and lens-induced glaucoma as the four leading etiologies of SG in Northwestern China.These findings emphasize the critical need for targeted prevention strategies and evidence-based health education programs among high-risk populations.Implementation of such initiatives will improve early detection,enable ophthalmologists to deliver timely therapeutic interventions,and ultimately reduce preventable vision loss in this region.展开更多
Although the concentration of fine particulate matter(PM_(2.5))is reducing continuously,the proportion of secondary organic aerosols(SOA)in PM_(2.5) and the O_(3) levels are increasing.This is causing severe complex a...Although the concentration of fine particulate matter(PM_(2.5))is reducing continuously,the proportion of secondary organic aerosols(SOA)in PM_(2.5) and the O_(3) levels are increasing.This is causing severe complex atmospheric pollution in North China.It is essential to identify and quantify the driving factors of SOA and O_(3),including the various pollution sources and meteorological factors.PM_(2.5) and volatile organic compounds(VOCs)samples were collected simultaneously in three cities in Shandong Province during different pollution scenarios from 2021 to 2023.Then,the carbonaceous aerosol and 99 VOC species were analyzed.Random forest(RF)combined with positive matrix factorization and an observation-based model(OBM)were used to quantify the key drivers of SOA and O_(3).Aromatic hydrocarbons were the main contributors to secondary organic aerosol potential(74.3%-89.9%),whereas alkenes contributed the most to the ozone formation potential(27.0%-62.3%).The RF modeling identified temperature and NOx as the dominant drivers of ozone formation.These accounted for 47.8%and 17.4%,respectively.Temperature showed a positive correlation with O_(3) because an increase in temperature can promote ozone formation.NOx had a significant negative correlation with O_(3),which was consistent with the conclusions from the sensitivity analysis of the OBM.The dominant contributors to SOA were vehicle emissions,solvent use,and industrial emissions.These accounted for 43.9%,18.2%,and 10.5%,respectively.An evident positive correlation existed between these emission sources and SOA.展开更多
Adolescent smoking constitutes a critical public health challenge as early initiation increases the risk of premature mortality and smoking-related chronic diseases due to longer exposure and higher cumulative tobacco...Adolescent smoking constitutes a critical public health challenge as early initiation increases the risk of premature mortality and smoking-related chronic diseases due to longer exposure and higher cumulative tobacco use^([1]).Adolescents are especially prone to developing persistent smoking habits,with many adult smokers having started before the age of 18.In China,16.7%of secondary school students have tried smoking and 4.7%are current smokers,highlighting the critical need for targeted tobacco control interventions among the youth.展开更多
Atmospheric oxidation capacity(AOC)refers to the oxidation capacity of atmospheric chemical processes for major pollutants.A comprehensive observation campaign was conducted on a typical PM_(2.5)pollution event in Uru...Atmospheric oxidation capacity(AOC)refers to the oxidation capacity of atmospheric chemical processes for major pollutants.A comprehensive observation campaign was conducted on a typical PM_(2.5)pollution event in Urumqi,Northwest China,from January 15 to February 15,2024.Four typical cases representing PM_(2.5)levels from non-polluted to heavily polluted periods were selected to estimate AOC,OH reactivity,their relationship with secondary components,and the HO_(x)budget in PM_(2.5)using the Framework for 0-D Atmospheric Modeling model.Aromatics and alkanes contributed 54%-79%and 18%-46%of secondary organic aerosols(SOA)formation,respectively.The sulfur oxidation ratio(SOR)and nitrogen oxidation ratio(NOR)increased with rising PM_(2.5)levels.As AOC increased,SOR showed the same trend,while NOR and SOA decreased slightly,and ammonia oxidation ratio values remained almost unchanged.OH radicals were the primary oxidants during the daytime,whereas NO_(3)played a dominant role at nighttime.CO(24%-51%),NO2(27%-34%),and alkenes(7%-12%)were the dominant contributors to OH reactivity.The HO_(2)+NO reaction pathway contributes 67%-84%to the production of OH,while Others(including carbonyl compounds photolysis,the permutation reactions of RO2,etc.),RO_(2)+NO and OH+CO reaction pathways were the main pathways for HO2 production.A comprehensive understanding of the interactions among AOC,SOA,and radical cycling is crucial for formulating effective air quality management strategies aimed at mitigating secondary pollution under diverse atmospheric conditions.展开更多
This study investigates the well-being of primary and secondary school teachers in Macao and the development of teacher community building within local schools.Drawing on semi-structured interviews with ten teachers f...This study investigates the well-being of primary and secondary school teachers in Macao and the development of teacher community building within local schools.Drawing on semi-structured interviews with ten teachers from diverse educational backgrounds,a reflexive thematic analysis identified six interrelated themes:(a)long working hours and hidden labor erode wellbeing,(b)lack of structural support,stress managed individually,(c)teacher communities remain formalistic,low collaboration efficacy,(d)opaque decision-making undermines participation and trust,(e)leadership style and empathy shape support and trust,and(f)stability and fairness of systems sustain teacher wellbeing.The findings reveal that teachers’well-being is shaped by the interplay between job demands,institutional support,and relational trust within schools.While personal coping strategies provide temporary relief,structural limitations and formalized teacher communities hinder sustainable development.The study extends the Job Demands-Resources and organizational justice frameworks by situating teacher well-being within the specific sociocultural and institutional context of Macao.It highlights the importance of empathetic leadership,transparent governance,and equitable workload systems for fostering both teacher well-being and community cohesion in Macao educational settings.展开更多
The reliable operation of power grid secondary equipment is an important guarantee for the safety and stability of the power system.However,various defects could be produced in the secondary equipment during longtermo...The reliable operation of power grid secondary equipment is an important guarantee for the safety and stability of the power system.However,various defects could be produced in the secondary equipment during longtermoperation.The complex relationship between the defect phenomenon andmulti-layer causes and the probabilistic influence of secondary equipment cannot be described through knowledge extraction and fusion technology by existing methods,which limits the real-time and accuracy of defect identification.Therefore,a defect recognition method based on the Bayesian network and knowledge graph fusion is proposed.The defect data of secondary equipment is transformed into the structured knowledge graph through knowledge extraction and fusion technology.The knowledge graph of power grid secondary equipment is mapped to the Bayesian network framework,combined with historical defect data,and introduced Noisy-OR nodes.The prior and conditional probabilities of the Bayesian network are then reasonably assigned to build a model that reflects the probability dependence between defect phenomena and potential causes in power grid secondary equipment.Defect identification of power grid secondary equipment is achieved by defect subgraph search based on the knowledge graph,and defect inference based on the Bayesian network.Practical application cases prove this method’s effectiveness in identifying secondary equipment defect causes,improving identification accuracy and efficiency.展开更多
This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shea...This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shear(VWS),using idealized numerical experiments.Results reveal that the SE develops greater radial extent when surface winds align with VWS compared to counter-aligned conditions.In alignment configurations,shear-enhanced surface winds on the right flank amplify surface enthalpy fluxes,thereby elevating boundary-layer entropy within the downshear outer-core region.Subsequently,more vigorous outer rainbands develop,inducing marked acceleration of tangential winds in the outer core preceding SE formation.The resultant radial expansion of supergradient winds near the boundary-layer top triggers widespread convective activity immediately beyond the inner core.Progressive axisymmetrization of this convective forcing ultimately generates an expansive SE structure.展开更多
1 Plant SecondaryMetabolism and Functional Biology Progress Plants have long been recognized as biochemical powerhouses,producing a vast array of compounds through their secondary metabolic pathways[1].Although histor...1 Plant SecondaryMetabolism and Functional Biology Progress Plants have long been recognized as biochemical powerhouses,producing a vast array of compounds through their secondary metabolic pathways[1].Although historically referred to as‘secondary’due to their perceived non-essential role in basic plant survival,it is now understood that these metabolites are integral to plant growth,development and adaptation to environmental challenges.Secondary metabolites,such as alkaloids,terpenoids,phenolics and flavonoids,serve as critical mediators of plant-environment interactions,conferring resistance to biotic and abiotic stressors[2].Beyond their ecological functions,these compounds are invaluable to humans,supporting industries ranging from pharmaceuticals and nutrition to agrochemicals and chemical additives.展开更多
The secondary cell wall(SCW)is essential for plant growth and development in vascular plants,and its biosynthesis is mainly controlled by a complex hierarchical regulatory network involving multiple transcription fact...The secondary cell wall(SCW)is essential for plant growth and development in vascular plants,and its biosynthesis is mainly controlled by a complex hierarchical regulatory network involving multiple transcription factors(TFs)at the transcription level.However,TFs that specifically regulate secondary xylem have not been widely reported.In this study,we described a poplar KNOTTED1-like homeobox(KNOX)TF PtoKNAT3a1,which was mainly expressed in the expanding xylem cells of stems.PtoKNAT3a1 overexpression caused fiber SCW thickening and increased all measured SCW compositions by upregulating the expression of SCW-biosynthetic genes and-associated TFs,but had no effect on the vessels of SCW.The opposite phenotype was observed in the PtoKNAT3a1-knockout lines.Hence,we further demonstrated that Pto-KNAT3a1 could physically interact with the NAC master switches PtoWND2A/3A to enhance the expression of downstream MYB TFs and SCW biosynthetic genes(including PtoMYB20,PtoMYB21,PtoMYB90,PtoCoMT2,PtoGT43B and PtoCesA8).Meanwhile,the studies also demonstrate that the KNAT3 has functional differentiation in xylem development.Taken together,these data suggest that the KNAT3a1-WND2A/3A module positively regulates fiber development of the secondary xylem in poplar via the WND2A/3A-mediated hierarchical regulatory network,and supplies useful information for fiber SCW formation.The research not only deepens the understanding of the hierarchical regulatory network affecting SCW formation but also supplies genetic resources and molecular targets for plant fiber utilization.展开更多
Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially...Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially among patients with poor functional outcomes.ICH is often accompanied by decreased consciousness and limb dysfunction.This seriously affects patients’ability to live independently.Although rapid advances in neurosurgery have greatly improved patient survival,there remains insufficient evidence that surgical treatment significantly improves long-term outcomes.With in-depth pathophysiological studies after ICH,increasing evidence has shown that secondary injury after ICH is related to long-term prognosis and that the key to secondary injury is various immune-mediated neuroinflammatory reactions after ICH.In basic and clinical studies of various systemic inflammatory diseases,triggering receptor expressed on myeloid cells 1/2(TREM-1/2),and the TREM receptor family is closely related to the inflammatory response.Various inflammatory diseases can be upregulated and downregulated through receptor intervention.How the TREM receptor functions after ICH,the types of results from intervention,and whether the outcomes can improve secondary brain injury and the long-term prognosis of patients are unknown.An analysis of relevant research results from basic and clinical trials revealed that the inhibition of TREM-1 and the activation of TREM-2 can alleviate the neuroinflammatory immune response,significantly improve the long-term prognosis of neurological function in patients with cerebral hemorrhage,and thus improve the ability of patients to live independently.展开更多
With the rapid development of new energy and the high proportion of new energy connected to the grid,energy storage has become the leading technology driving significant adjustments in the global energy landscape.Elec...With the rapid development of new energy and the high proportion of new energy connected to the grid,energy storage has become the leading technology driving significant adjustments in the global energy landscape.Electrochemical energy storage,as the most popular and promising energy storage method,has received extensive attention.Currently,the most widely used energy storage method is metal-ion secondary batteries,whose performance mainly depends on the cathode material.Prussian blue analogues(PBAs)have a unique open framework structures that allow quick and reversible insertion/extraction of metal ions such as Na^(+),K^(+),Zn^(2+),Li^(+)etc.,thus attracting widespread attention.The advantages of simple synthesis process,abundant resources,and low cost also distinguish it from its counterparts.Unfortunately,the crystal water and structural defects in the PBAs lattice that is generated during the synthesis process,as well as the low Na content,significantly affect their electrochemical performance.This paper focuses on PBAs’synthesis methods,crystal structure,modification strategies,and their potential applications as cathode materials for various metal ion secondary batteries and looks forward to their future development direction.展开更多
The number of secondary feathers varies among orders of birds with some orders exhibiting a positive relationship with ulna length,whereas in other orders secondary number is invariant.This difference has implications...The number of secondary feathers varies among orders of birds with some orders exhibiting a positive relationship with ulna length,whereas in other orders secondary number is invariant.This difference has implications for scaling of the width of the feather vane within orders.In those species where the number of secondary remiges is invariant with ulna length,vane width should scale isometrically with ulna size to maintain an aerodynamic flight surface.Where feather count increases with increasing ulna length then vane width should exhibit negative allometry.Vane length should also correlate with ulna length,irrespective of the number of feathers.Data were compiled from an online library of images for the vane length and the width of the vane at 50%of the vane length for the fifth secondary feather for 209 bird species from 24 different orders.The results supported the hypotheses that vane width is a function of ulna size,and the number of secondary feathers as associated with different orders.Vane length was unaffected by the number of secondaries but varied between orders.The results suggest that birds have solved the problem of maintaining the aerodynamic surface of the proximal wing in two ways.Hence as ulna length increases the first solution involves more feathers that exhibit negative allometry for vane width,or in the second where feather count doesn't change,the vane width simply scales isometrically.The implications for the mechanical properties of the vane,and how it affects wing function,have not yet been explored in a range of birds.展开更多
Over the past decades,the expansion of natu-ral secondary forests has played a crucial role in offsetting the loss of primary forests and combating climate change.Despite this,there is a gap in our understanding of ho...Over the past decades,the expansion of natu-ral secondary forests has played a crucial role in offsetting the loss of primary forests and combating climate change.Despite this,there is a gap in our understanding of how tree species’growth and mortality patterns vary with eleva-tion in these secondary forests.In this study,we analyzed data from two censuses(spanning a five-year interval)conducted in both evergreen broadleaved forests(EBF)and temperate coniferous forests(TCF),which have been recovering for half a century,across elevation gradients in a subtropical mountain region,Mount Wuyi,China.The results indicated that the relative growth rate(RGR)of EBF(0.028±0.001 cm·cm^(-1)·a^(-1))and the mortality rate(MR)(20.03%±1.70%)were 27.3%and 16.4%higher,respec-tively,than those of TCF.Interestingly,the trade-off between RGR and MR in EBF weakened as elevation increased,a trend not observed in TCF.Conversely,TCF consistently showed a stronger trade-off between RGR and MR compared to EBF.Generalized linear mixed models revealed that ele-vation influences RGR both directly and indirectly through its interactions with slope,crown competition index(CCI),and tree canopy height(CH).However,tree mortality did not show a significant correlation with elevation.Additionally,DBH significantly influenced both tree growth and mortal-ity,whereas and CH and CCI had opposite effects on tree growth between EBF and TCF.Our study underscores the importance of elevation in shaping the population dynamics and the biomass carbon sink balance of mountain forests.These insights enhance our understanding of tree species’life strategies,enabling more accurate predictions of forest dynamics and their response to environmental changes.展开更多
Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the...Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.展开更多
The article"Secondary diabetes due to different etiologies:Four case reports"by Song et al,published in the World Journal of Clinical Cases,delves into the identi-fication of rare causes of secondary diabete...The article"Secondary diabetes due to different etiologies:Four case reports"by Song et al,published in the World Journal of Clinical Cases,delves into the identi-fication of rare causes of secondary diabetes and emphasizes the necessity for healthcare professionals to recognize these conditions.Failure to do so can result in treatment delays and compromised patient outcomes.The article discusses spe-cific types of diabetes,including maturity onset of diabetes in young,pancreas-related diseases,endocrinopathies,drug-induced diabetes,infections,and con-genital genetic syndromes associated with diabetes mellitus.Case summaries highlight how patients with secondary diabetes,stemming from conditions such as Williams-Beuren syndrome and pituitary adenoma,often exhibit distinct characteristics overlooked in clinical practice.The authors stress the importance of a holistic diagnostic approach and advocate for proactive management through early intervention,including genetic tests and antibody detection.Increased awa-reness and education are crucial for timely identification and proper management,ultimately improving patient well-being.These findings prompt a call to action for healthcare professionals to consider rare causes of secondary diabetes,facili-tating better glycemic control and overall patient care.展开更多
The mechanical properties of secondary cells are crucial to the safety and reliability of battery packs,which can fail due to extrusion and vibration in a vehicle crash.To analyze the structural response of the second...The mechanical properties of secondary cells are crucial to the safety and reliability of battery packs,which can fail due to extrusion and vibration in a vehicle crash.To analyze the structural response of the secondary cell and its other dynamic behaviors,the experiment and some numerical simulations were carried out based on single reference impact testing.Then,an equivalent constitutive relationship of the secondary cell was proposed to reveal the dynamic properties and used to guide the safety estimation of the battery pack.As the input parameter to the finite element model,the equivalent constitutive relationship,including but not limited to the elastic modulus and stain-stress curve,determines the simulation precision of the battery packs.Compared to the experimental results of the natural frequency of the battery pack,the simulation error is below 2%when the elastic modulus of the secondary cell in the battery pack has been verified.展开更多
Two-dimensional(2D)precursor molecules-based surface treatment on three-dimensional(3D)lead halide perovskite(PVSK)has achieved huge successes,the in-depth understanding of the modification mechanism remains an urgent...Two-dimensional(2D)precursor molecules-based surface treatment on three-dimensional(3D)lead halide perovskite(PVSK)has achieved huge successes,the in-depth understanding of the modification mechanism remains an urgent need.Here the effect of alkyl-chain length on the reaction dynamics between alkylammonium salts(XI)and 3D PVSK matrix is studied,through examination of surface morphological and crystallographic properties of the 3D PVSK matrix.It is observed that the average crystallite size of 3D PVSK increases as XI is either spin-coated on 3D PVSK or penetrated through carbon-electrode(during the“in-situ healing”process).Secondary growth is observed for 3D PVSK,which is related to ion-exchanging reactions.Prolonging alkyl-chain length favors the secondary growth.Besides,the formation dynamics of 2D PVSK are studied.Adding alkyl-chain length increases the yields.The observations are thoroughly discussed with respect to the steric-hindrance effect held by alky-chains of XI molecule.The improved crystallization of 3D PVSK and increased yields of 2D PVSK help accelerate charge extraction and reduce recombination across the interface between PVSK and carbon-electrode(CE).Tuning alkyl-chain length of XI molecules,and the mass ratio between XI molecules and carbon black could mitigate the“in-situ healing”effect.Power conversion efficiency(PCE)of the carbonelectrode-based hole-conductor-free planar perovskite solar cells has been upgraded from 14% to 17%,and further upgraded to 20.4% by utilizing relatively thick CEs.Thanks to the hydrophobicity of long alkyl-chains owned by XI molecules,prolonged stability has been achieved on unsealed devices at the high-moisture environment(RH≈85%),meanwhile,shelf-stability up to 6400 h has been achieved.This study deepens the understanding of the 2D precursor-basing modification strategies.展开更多
基金Project supported by the National Natural Science Foundation of China(No.32160108)the Science and Technology Special Fund of Hainan Province(No.ZDYF2024SHFZ116)+2 种基金the Specific Research Fund of the Innovation Center for Academicians of Hainan Province(No.YSPTZX202309)the Scientific Research Project of Hainan Higher Education Institutions(No.Hnky2022ZD-6)the Hainan Normal University National College Student Innovation Training Program(No.202411658006)。
文摘new heterocyclic dipeptide with a highly functionalized 1,2-oxazadecaline core,named trichodermamide H(1),and three known analogues,along with three known polyketides,were isolated from the fermentation extract of the mangrovederived fungus Penicillium janthinellum XLN32122.The structure of 1 was elucidated on the basis of extensive 1D and 2D NMR spectra data analysis,HR-ESI-MS,electronic circular dichroism(ECD)calculations.Trichodermamide B(3)exhibited better inhibitory effect on nitric oxide(NO)production in lipopolysaccharide(LPS)induced RAW 264.7 cells with an IC_(50)value of(13.13±0.005)μmol/L than that of the positive control dexamethasone[IC_(50)=(136.84±1.33)μmol/L].Compound 3 exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus(MRSA)with an IC_(50)value of 12.5μg/mL,while the positive control vancomycin showed an IC_(50)value of 1.563μg/mL.
基金supported by the World Bank Group through the Regional Centre of Excellence on Sustainable Cities in Africa(CERViDA-DOUNEDON),grant numbers 6512-TG and 5360-TG.
文摘Although progress has been made nationally in terms of drinking water coverage,access remains a significant challenge in Togo’s secondary cities,particularly in Noèpéand Kovié.These areas are experiencing rapid urbanization and sustained population growth,which is putting increasing pressure on often dilapidated infrastructure.This study aims to examine the institutional,regulatory and organizational mechanisms that shape water governance in Noèpéand Kovié,to identify the main obstacles and potential pathways towards equitable and sustainable access to drinking water.The research combined a literature review with qualitative fieldwork,including 67 semi-structured interviews and focus groups with institutional actors,municipal authorities and community association.Thematic analysis was used to triangulate institutional discourse,policy documents and community perspectives.The findings reveal that governance is hindered by institutional fragmentation,weak inter-institutional coordination,compounded by centralized governance.Community-based models,although widespread,suffer from lack of professionalization,financial fragility,weak community participation and conflicts interest.Infrastructure deficits,dependence on ad hoc external funding,and limited regulation exacerbate service inequalities.To address these challenges,this study concludes that water governance in secondary cities must be adapted to institutional and regulatory frameworks while taking local specifics into account.Strengthening institutional and community capacities,updating stakeholder mapping,developing participatory governance mechanisms and establishing shared governance mechanisms are essential.Local master plan aligned with urban planning strategies are recommended to anticipate demographic pressures and climate variability.Such reforms would help to ensure sustainable access to drinking water.
基金Supported by the National Natural Science Foundation of China(No.82070964,No.82571210)Shaanxi Science Fund for Distinguished Young Scholars(No.2022JC-60)+3 种基金the International Scientific and Technological Cooperation Projects(No.2024GH-YBXM-20)the Open Research Funds of the State Key Laboratory of Ophthalmology(No.83000-32030002)Education Department of Shaanxi Provincial Government for Youth Innovation Team Research Program Project(No.23JP151,No.23JP150)General Projects of Hospital-level Research Topics in the Second Affiliated Hospital of Xi’an Medical University(No.22KY0111).
文摘AIM:To investigate the etiology and clinical characteristics of hospitalized secondary glaucoma(SG)patients in northwestern China.METHODS:A cross-sectional study was conducted involving SG patients hospitalized between July 2024 and January 2025.Clinical data were collected,including medical history,best-corrected visual acuity(BCVA),intraocular pressure(IOP),slit-lamp examination,gonioscopic findings,and fundus examination.Demographic characteristics,etiological factors,and treatment modalities were analyzed.RESULTS:A total of 67 patients(82 eyes)were enrolled,aged 7 to 90y.Males accounted for 54.0%(36/67),and 22.4%(15/67)of patients had bilateral involvement.The predominant etiologies of SG were neovascular glaucoma(NVG;25.4%),traumatic glaucoma(23.9%),uveitic glaucoma(20.9%),and lens-induced glaucoma(14.9%),collectively accounting for 85.1%of all cases.The peak age-specific incidence occurred in the 50-59 years age group(32.8%,22/67),while NVG was prevalent across the 40-79 years age range.IOP of the 82 affected eyes was stratified into five severity tiers:22-29 mm Hg(15 eyes,18.3%),30-39 mm Hg(14 eyes,17.1%),40-49 mm Hg(13 eyes,15.9%),50-59 mm Hg(20 eyes,24.4%),and≥60 mm Hg(20 eyes,24.4%).The overall mean IOP was 45.2±12.3 mm Hg,indicating a significant pathological elevation.Surgical intervention was required in 46.3%of cases,predominantly for NVG,lensinduced glaucoma,and traumatic glaucoma—conditions prone to rapid IOP elevation.The etiologies with the highest surgical intervention rates were malignant glaucoma,pigmentary glaucoma,lens-induced glaucoma,and NVG.In contrast,uveitic glaucoma cases were primarily managed with targeted anti-inflammatory therapy,which effectively controlled IOP in the early disease stages and potentially obviated the need for surgery.CONCLUSION:This study identifies NVG,traumatic glaucoma,uveitic glaucoma,and lens-induced glaucoma as the four leading etiologies of SG in Northwestern China.These findings emphasize the critical need for targeted prevention strategies and evidence-based health education programs among high-risk populations.Implementation of such initiatives will improve early detection,enable ophthalmologists to deliver timely therapeutic interventions,and ultimately reduce preventable vision loss in this region.
基金supported by Qingdao Natural Science Foundation(No. 23-2-1-224-zyyd-jch)。
文摘Although the concentration of fine particulate matter(PM_(2.5))is reducing continuously,the proportion of secondary organic aerosols(SOA)in PM_(2.5) and the O_(3) levels are increasing.This is causing severe complex atmospheric pollution in North China.It is essential to identify and quantify the driving factors of SOA and O_(3),including the various pollution sources and meteorological factors.PM_(2.5) and volatile organic compounds(VOCs)samples were collected simultaneously in three cities in Shandong Province during different pollution scenarios from 2021 to 2023.Then,the carbonaceous aerosol and 99 VOC species were analyzed.Random forest(RF)combined with positive matrix factorization and an observation-based model(OBM)were used to quantify the key drivers of SOA and O_(3).Aromatic hydrocarbons were the main contributors to secondary organic aerosol potential(74.3%-89.9%),whereas alkenes contributed the most to the ozone formation potential(27.0%-62.3%).The RF modeling identified temperature and NOx as the dominant drivers of ozone formation.These accounted for 47.8%and 17.4%,respectively.Temperature showed a positive correlation with O_(3) because an increase in temperature can promote ozone formation.NOx had a significant negative correlation with O_(3),which was consistent with the conclusions from the sensitivity analysis of the OBM.The dominant contributors to SOA were vehicle emissions,solvent use,and industrial emissions.These accounted for 43.9%,18.2%,and 10.5%,respectively.An evident positive correlation existed between these emission sources and SOA.
基金supported by the World Health Organization Global Youth Tobacco Survey(WPDHP1206671)the Global Health Capacity Building and Tobacco Control Project:Tobacco Epidemic Monitoring and Comprehensive Tobacco Control Intervention。
文摘Adolescent smoking constitutes a critical public health challenge as early initiation increases the risk of premature mortality and smoking-related chronic diseases due to longer exposure and higher cumulative tobacco use^([1]).Adolescents are especially prone to developing persistent smoking habits,with many adult smokers having started before the age of 18.In China,16.7%of secondary school students have tried smoking and 4.7%are current smokers,highlighting the critical need for targeted tobacco control interventions among the youth.
基金supported by the Chinese Research Academy of Envi-ronmental Sciences(No.2024YSKY-57)the National Key Research and Development Program of China(No.2017YFC0212501)Xinjiang Uygur Autonomous Region Environmental Monitoring Central Station(No.HYZB-2022-0320).
文摘Atmospheric oxidation capacity(AOC)refers to the oxidation capacity of atmospheric chemical processes for major pollutants.A comprehensive observation campaign was conducted on a typical PM_(2.5)pollution event in Urumqi,Northwest China,from January 15 to February 15,2024.Four typical cases representing PM_(2.5)levels from non-polluted to heavily polluted periods were selected to estimate AOC,OH reactivity,their relationship with secondary components,and the HO_(x)budget in PM_(2.5)using the Framework for 0-D Atmospheric Modeling model.Aromatics and alkanes contributed 54%-79%and 18%-46%of secondary organic aerosols(SOA)formation,respectively.The sulfur oxidation ratio(SOR)and nitrogen oxidation ratio(NOR)increased with rising PM_(2.5)levels.As AOC increased,SOR showed the same trend,while NOR and SOA decreased slightly,and ammonia oxidation ratio values remained almost unchanged.OH radicals were the primary oxidants during the daytime,whereas NO_(3)played a dominant role at nighttime.CO(24%-51%),NO2(27%-34%),and alkenes(7%-12%)were the dominant contributors to OH reactivity.The HO_(2)+NO reaction pathway contributes 67%-84%to the production of OH,while Others(including carbonyl compounds photolysis,the permutation reactions of RO2,etc.),RO_(2)+NO and OH+CO reaction pathways were the main pathways for HO2 production.A comprehensive understanding of the interactions among AOC,SOA,and radical cycling is crucial for formulating effective air quality management strategies aimed at mitigating secondary pollution under diverse atmospheric conditions.
文摘This study investigates the well-being of primary and secondary school teachers in Macao and the development of teacher community building within local schools.Drawing on semi-structured interviews with ten teachers from diverse educational backgrounds,a reflexive thematic analysis identified six interrelated themes:(a)long working hours and hidden labor erode wellbeing,(b)lack of structural support,stress managed individually,(c)teacher communities remain formalistic,low collaboration efficacy,(d)opaque decision-making undermines participation and trust,(e)leadership style and empathy shape support and trust,and(f)stability and fairness of systems sustain teacher wellbeing.The findings reveal that teachers’well-being is shaped by the interplay between job demands,institutional support,and relational trust within schools.While personal coping strategies provide temporary relief,structural limitations and formalized teacher communities hinder sustainable development.The study extends the Job Demands-Resources and organizational justice frameworks by situating teacher well-being within the specific sociocultural and institutional context of Macao.It highlights the importance of empathetic leadership,transparent governance,and equitable workload systems for fostering both teacher well-being and community cohesion in Macao educational settings.
基金supported by the State Grid Southwest Branch Project“Research on Defect Diagnosis and Early Warning Technology of Relay Protection and Safety Automation Devices Based on Multi-Source Heterogeneous Defect Data”.
文摘The reliable operation of power grid secondary equipment is an important guarantee for the safety and stability of the power system.However,various defects could be produced in the secondary equipment during longtermoperation.The complex relationship between the defect phenomenon andmulti-layer causes and the probabilistic influence of secondary equipment cannot be described through knowledge extraction and fusion technology by existing methods,which limits the real-time and accuracy of defect identification.Therefore,a defect recognition method based on the Bayesian network and knowledge graph fusion is proposed.The defect data of secondary equipment is transformed into the structured knowledge graph through knowledge extraction and fusion technology.The knowledge graph of power grid secondary equipment is mapped to the Bayesian network framework,combined with historical defect data,and introduced Noisy-OR nodes.The prior and conditional probabilities of the Bayesian network are then reasonably assigned to build a model that reflects the probability dependence between defect phenomena and potential causes in power grid secondary equipment.Defect identification of power grid secondary equipment is achieved by defect subgraph search based on the knowledge graph,and defect inference based on the Bayesian network.Practical application cases prove this method’s effectiveness in identifying secondary equipment defect causes,improving identification accuracy and efficiency.
基金jointly supported by the National Natural Science Foundation of China[grant numbers U2342202,42175005,and 42175016]the Qing Lan Project[grant number R2023Q06]。
文摘This study investigates the width of the secondary eyewall(SE)immediately following its formation in tropical cyclones with surface environmental winds aligned and counter-aligned with environmental vertical wind shear(VWS),using idealized numerical experiments.Results reveal that the SE develops greater radial extent when surface winds align with VWS compared to counter-aligned conditions.In alignment configurations,shear-enhanced surface winds on the right flank amplify surface enthalpy fluxes,thereby elevating boundary-layer entropy within the downshear outer-core region.Subsequently,more vigorous outer rainbands develop,inducing marked acceleration of tangential winds in the outer core preceding SE formation.The resultant radial expansion of supergradient winds near the boundary-layer top triggers widespread convective activity immediately beyond the inner core.Progressive axisymmetrization of this convective forcing ultimately generates an expansive SE structure.
基金supported by High Level Talents Research Initiation Fund of West Anhui University(WGKQ2022025)Quality Engineering Project of Anhui Province(2024zybj032)+1 种基金Quality Engineering Project of West Anhui University(wxxy2024011)Development of Big Data Integration and Analysis Platform for Traditional Chinese Medicine Genomics(0045025050).
文摘1 Plant SecondaryMetabolism and Functional Biology Progress Plants have long been recognized as biochemical powerhouses,producing a vast array of compounds through their secondary metabolic pathways[1].Although historically referred to as‘secondary’due to their perceived non-essential role in basic plant survival,it is now understood that these metabolites are integral to plant growth,development and adaptation to environmental challenges.Secondary metabolites,such as alkaloids,terpenoids,phenolics and flavonoids,serve as critical mediators of plant-environment interactions,conferring resistance to biotic and abiotic stressors[2].Beyond their ecological functions,these compounds are invaluable to humans,supporting industries ranging from pharmaceuticals and nutrition to agrochemicals and chemical additives.
基金supported by grants from the Biological Breeding-National Science and Technology Major Project(Grant No.2023ZD0406803)the National Key Research and Development Program(Grant No.2021YFD2200204)+2 种基金the National Science Foundation of China(Grant No.32071791 and 32271835)the Chongqing Youth Top Talent Program(Grant No.CQYC201905028)Fundamental Research Funds for the Central Universities(Grant No.XDJK2020B036).
文摘The secondary cell wall(SCW)is essential for plant growth and development in vascular plants,and its biosynthesis is mainly controlled by a complex hierarchical regulatory network involving multiple transcription factors(TFs)at the transcription level.However,TFs that specifically regulate secondary xylem have not been widely reported.In this study,we described a poplar KNOTTED1-like homeobox(KNOX)TF PtoKNAT3a1,which was mainly expressed in the expanding xylem cells of stems.PtoKNAT3a1 overexpression caused fiber SCW thickening and increased all measured SCW compositions by upregulating the expression of SCW-biosynthetic genes and-associated TFs,but had no effect on the vessels of SCW.The opposite phenotype was observed in the PtoKNAT3a1-knockout lines.Hence,we further demonstrated that Pto-KNAT3a1 could physically interact with the NAC master switches PtoWND2A/3A to enhance the expression of downstream MYB TFs and SCW biosynthetic genes(including PtoMYB20,PtoMYB21,PtoMYB90,PtoCoMT2,PtoGT43B and PtoCesA8).Meanwhile,the studies also demonstrate that the KNAT3 has functional differentiation in xylem development.Taken together,these data suggest that the KNAT3a1-WND2A/3A module positively regulates fiber development of the secondary xylem in poplar via the WND2A/3A-mediated hierarchical regulatory network,and supplies useful information for fiber SCW formation.The research not only deepens the understanding of the hierarchical regulatory network affecting SCW formation but also supplies genetic resources and molecular targets for plant fiber utilization.
基金Supported by Shanxi Provincial Key Research and Development Plan Project,No.2020ZDLSF01-02Doctor Foundation of the Second Affiliated Hospital of Xi’an Medical University,No.X2Y-R11.
文摘Intracerebral hemorrhage(ICH)is a common severe emergency in neurosurgery,causing tremendous economic pressure on families and society and devastating effects on patients both physically and psychologically,especially among patients with poor functional outcomes.ICH is often accompanied by decreased consciousness and limb dysfunction.This seriously affects patients’ability to live independently.Although rapid advances in neurosurgery have greatly improved patient survival,there remains insufficient evidence that surgical treatment significantly improves long-term outcomes.With in-depth pathophysiological studies after ICH,increasing evidence has shown that secondary injury after ICH is related to long-term prognosis and that the key to secondary injury is various immune-mediated neuroinflammatory reactions after ICH.In basic and clinical studies of various systemic inflammatory diseases,triggering receptor expressed on myeloid cells 1/2(TREM-1/2),and the TREM receptor family is closely related to the inflammatory response.Various inflammatory diseases can be upregulated and downregulated through receptor intervention.How the TREM receptor functions after ICH,the types of results from intervention,and whether the outcomes can improve secondary brain injury and the long-term prognosis of patients are unknown.An analysis of relevant research results from basic and clinical trials revealed that the inhibition of TREM-1 and the activation of TREM-2 can alleviate the neuroinflammatory immune response,significantly improve the long-term prognosis of neurological function in patients with cerebral hemorrhage,and thus improve the ability of patients to live independently.
基金supported by the National Natural Science Foundation of China(No.52072217)the National Key Research and Development Program of China(No.2022YFB3807700)+2 种基金the Joint Funds of the Hubei Natural Science Foundation Innovation and Development(No.2022CFD034)Hubei Natural Science Foundation Innovation Group Project(No.2022CFA020)the Major Technological Innovation Project of Hubei Science and Technology Department(No.2019AAA164).
文摘With the rapid development of new energy and the high proportion of new energy connected to the grid,energy storage has become the leading technology driving significant adjustments in the global energy landscape.Electrochemical energy storage,as the most popular and promising energy storage method,has received extensive attention.Currently,the most widely used energy storage method is metal-ion secondary batteries,whose performance mainly depends on the cathode material.Prussian blue analogues(PBAs)have a unique open framework structures that allow quick and reversible insertion/extraction of metal ions such as Na^(+),K^(+),Zn^(2+),Li^(+)etc.,thus attracting widespread attention.The advantages of simple synthesis process,abundant resources,and low cost also distinguish it from its counterparts.Unfortunately,the crystal water and structural defects in the PBAs lattice that is generated during the synthesis process,as well as the low Na content,significantly affect their electrochemical performance.This paper focuses on PBAs’synthesis methods,crystal structure,modification strategies,and their potential applications as cathode materials for various metal ion secondary batteries and looks forward to their future development direction.
文摘The number of secondary feathers varies among orders of birds with some orders exhibiting a positive relationship with ulna length,whereas in other orders secondary number is invariant.This difference has implications for scaling of the width of the feather vane within orders.In those species where the number of secondary remiges is invariant with ulna length,vane width should scale isometrically with ulna size to maintain an aerodynamic flight surface.Where feather count increases with increasing ulna length then vane width should exhibit negative allometry.Vane length should also correlate with ulna length,irrespective of the number of feathers.Data were compiled from an online library of images for the vane length and the width of the vane at 50%of the vane length for the fifth secondary feather for 209 bird species from 24 different orders.The results supported the hypotheses that vane width is a function of ulna size,and the number of secondary feathers as associated with different orders.Vane length was unaffected by the number of secondaries but varied between orders.The results suggest that birds have solved the problem of maintaining the aerodynamic surface of the proximal wing in two ways.Hence as ulna length increases the first solution involves more feathers that exhibit negative allometry for vane width,or in the second where feather count doesn't change,the vane width simply scales isometrically.The implications for the mechanical properties of the vane,and how it affects wing function,have not yet been explored in a range of birds.
基金funded by the National Natural Science Foundation of China(Grant No.32271872).
文摘Over the past decades,the expansion of natu-ral secondary forests has played a crucial role in offsetting the loss of primary forests and combating climate change.Despite this,there is a gap in our understanding of how tree species’growth and mortality patterns vary with eleva-tion in these secondary forests.In this study,we analyzed data from two censuses(spanning a five-year interval)conducted in both evergreen broadleaved forests(EBF)and temperate coniferous forests(TCF),which have been recovering for half a century,across elevation gradients in a subtropical mountain region,Mount Wuyi,China.The results indicated that the relative growth rate(RGR)of EBF(0.028±0.001 cm·cm^(-1)·a^(-1))and the mortality rate(MR)(20.03%±1.70%)were 27.3%and 16.4%higher,respec-tively,than those of TCF.Interestingly,the trade-off between RGR and MR in EBF weakened as elevation increased,a trend not observed in TCF.Conversely,TCF consistently showed a stronger trade-off between RGR and MR compared to EBF.Generalized linear mixed models revealed that ele-vation influences RGR both directly and indirectly through its interactions with slope,crown competition index(CCI),and tree canopy height(CH).However,tree mortality did not show a significant correlation with elevation.Additionally,DBH significantly influenced both tree growth and mortal-ity,whereas and CH and CCI had opposite effects on tree growth between EBF and TCF.Our study underscores the importance of elevation in shaping the population dynamics and the biomass carbon sink balance of mountain forests.These insights enhance our understanding of tree species’life strategies,enabling more accurate predictions of forest dynamics and their response to environmental changes.
文摘Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.
文摘The article"Secondary diabetes due to different etiologies:Four case reports"by Song et al,published in the World Journal of Clinical Cases,delves into the identi-fication of rare causes of secondary diabetes and emphasizes the necessity for healthcare professionals to recognize these conditions.Failure to do so can result in treatment delays and compromised patient outcomes.The article discusses spe-cific types of diabetes,including maturity onset of diabetes in young,pancreas-related diseases,endocrinopathies,drug-induced diabetes,infections,and con-genital genetic syndromes associated with diabetes mellitus.Case summaries highlight how patients with secondary diabetes,stemming from conditions such as Williams-Beuren syndrome and pituitary adenoma,often exhibit distinct characteristics overlooked in clinical practice.The authors stress the importance of a holistic diagnostic approach and advocate for proactive management through early intervention,including genetic tests and antibody detection.Increased awa-reness and education are crucial for timely identification and proper management,ultimately improving patient well-being.These findings prompt a call to action for healthcare professionals to consider rare causes of secondary diabetes,facili-tating better glycemic control and overall patient care.
基金supported by the 2019 Postdoctoral Research Project funded by Hefei Municipal Bureau of Human Resources and Social Security and the National key R&D Program of China(2017YFB0102101).
文摘The mechanical properties of secondary cells are crucial to the safety and reliability of battery packs,which can fail due to extrusion and vibration in a vehicle crash.To analyze the structural response of the secondary cell and its other dynamic behaviors,the experiment and some numerical simulations were carried out based on single reference impact testing.Then,an equivalent constitutive relationship of the secondary cell was proposed to reveal the dynamic properties and used to guide the safety estimation of the battery pack.As the input parameter to the finite element model,the equivalent constitutive relationship,including but not limited to the elastic modulus and stain-stress curve,determines the simulation precision of the battery packs.Compared to the experimental results of the natural frequency of the battery pack,the simulation error is below 2%when the elastic modulus of the secondary cell in the battery pack has been verified.
基金financial support of the National Natural Science Foundation of China(NSFC,No.62374185)the Key Scientific Research Project of Education Department of Hunan Province(No.22A0005)the financial support from the Fundamental Research Funds for the Central South University(No.2024ZZTS0478)。
文摘Two-dimensional(2D)precursor molecules-based surface treatment on three-dimensional(3D)lead halide perovskite(PVSK)has achieved huge successes,the in-depth understanding of the modification mechanism remains an urgent need.Here the effect of alkyl-chain length on the reaction dynamics between alkylammonium salts(XI)and 3D PVSK matrix is studied,through examination of surface morphological and crystallographic properties of the 3D PVSK matrix.It is observed that the average crystallite size of 3D PVSK increases as XI is either spin-coated on 3D PVSK or penetrated through carbon-electrode(during the“in-situ healing”process).Secondary growth is observed for 3D PVSK,which is related to ion-exchanging reactions.Prolonging alkyl-chain length favors the secondary growth.Besides,the formation dynamics of 2D PVSK are studied.Adding alkyl-chain length increases the yields.The observations are thoroughly discussed with respect to the steric-hindrance effect held by alky-chains of XI molecule.The improved crystallization of 3D PVSK and increased yields of 2D PVSK help accelerate charge extraction and reduce recombination across the interface between PVSK and carbon-electrode(CE).Tuning alkyl-chain length of XI molecules,and the mass ratio between XI molecules and carbon black could mitigate the“in-situ healing”effect.Power conversion efficiency(PCE)of the carbonelectrode-based hole-conductor-free planar perovskite solar cells has been upgraded from 14% to 17%,and further upgraded to 20.4% by utilizing relatively thick CEs.Thanks to the hydrophobicity of long alkyl-chains owned by XI molecules,prolonged stability has been achieved on unsealed devices at the high-moisture environment(RH≈85%),meanwhile,shelf-stability up to 6400 h has been achieved.This study deepens the understanding of the 2D precursor-basing modification strategies.
