Alzheimer's disease,a progressively degenerative neurological disorder,is the most common cause of dementia in the elderly.While its precise etiology remains unclear,researchers have identified diverse pathologica...Alzheimer's disease,a progressively degenerative neurological disorder,is the most common cause of dementia in the elderly.While its precise etiology remains unclear,researchers have identified diverse pathological characteristics and molecular pathways associated with its progression.Advances in scientific research have increasingly highlighted the crucial role of non-coding RNAs in the progression of Alzheimer's disease.These non-coding RNAs regulate several biological processes critical to the advancement of the disease,offering promising potential as therapeutic targets and diagnostic biomarkers.Therefore,this review aims to investigate the underlying mechanisms of Alzheimer's disease onset,with a particular focus on microRNAs,long non-coding RNAs,and circular RNAs associated with the disease.The review elucidates the potential pathogenic processes of Alzheimer's disease and provides a detailed description of the synthesis mechanisms of the three aforementioned non-coding RNAs.It comprehensively summarizes the various non-coding RNAs that have been identified to play key regulatory roles in Alzheimer's disease,as well as how these noncoding RNAs influence the disease's progression by regulating gene expression and protein functions.For example,miR-9 targets the UBE4B gene,promoting autophagy-mediated degradation of Tau protein,thereby reducing Tau accumulation and delaying Alzheimer's disease progression.Conversely,the long non-coding RNA BACE1-AS stabilizes BACE1 mRNA,promoting the generation of amyloid-βand accelerating Alzheimer's disease development.Additionally,circular RNAs play significant roles in regulating neuroinflammatory responses.By integrating insights from these regulatory mechanisms,there is potential to discover new therapeutic targets and potential biomarkers for early detection and management of Alzheimer's disease.This review aims to enhance the understanding of the relationship between Alzheimer's disease and non-coding RNAs,potentially paving the way for early detection and novel treatment strategies.展开更多
The Si Tian project,designed to utilize 60 telescopes distributed across multiple sites in China,is a next-generation timedomain survey initiative.As a pathfinder for the Si Tian project,the Mini-Si Tian(MST)has been ...The Si Tian project,designed to utilize 60 telescopes distributed across multiple sites in China,is a next-generation timedomain survey initiative.As a pathfinder for the Si Tian project,the Mini-Si Tian(MST)has been proposed and implemented to test the Si Tian’s brain and data pipeline,and to evaluate the feasibility of its technology and science cases.Mounted at the Xinglong Observatory,the MST project comprises three 30 cm telescopes and has been operated since 2022 November.Each telescope of the MST possesses a large field of view,covering 2°.29×1°.53 FOV,and is equipped withg',r'andi'filters,respectively.Acting as the pioneer of the forthcoming Si Tian project,the MST is dedicated to the discovery of variable stars,transients,and outburst events,and has already obtained some interesting scientific results.In this paper,we will summarize the first-two-year operation of the MST project.展开更多
For the diagnostics and health management of lithium-ion batteries,numerous models have been developed to understand their degradation characteristics.These models typically fall into two categories:data-driven models...For the diagnostics and health management of lithium-ion batteries,numerous models have been developed to understand their degradation characteristics.These models typically fall into two categories:data-driven models and physical models,each offering unique advantages but also facing limitations.Physics-informed neural networks(PINNs)provide a robust framework to integrate data-driven models with physical principles,ensuring consistency with underlying physics while enabling generalization across diverse operational conditions.This study introduces a PINN-based approach to reconstruct open circuit voltage(OCV)curves and estimate key ageing parameters at both the cell and electrode levels.These parameters include available capacity,electrode capacities,and lithium inventory capacity.The proposed method integrates OCV reconstruction models as functional components into convolutional neural networks(CNNs)and is validated using a public dataset.The results reveal that the estimated ageing parameters closely align with those obtained through offline OCV tests,with errors in reconstructed OCV curves remaining within 15 mV.This demonstrates the ability of the method to deliver fast and accurate degradation diagnostics at the electrode level,advancing the potential for precise and efficient battery health management.展开更多
Recombinant human growth hormone(rhGH)has been widely used for the treatment of disorders associated with GH deficiency and multiple clinical indications[1].Accurate determination of biological activity is essential i...Recombinant human growth hormone(rhGH)has been widely used for the treatment of disorders associated with GH deficiency and multiple clinical indications[1].Accurate determination of biological activity is essential in the development,registration,and quality control of rhGH pharmaceutical products[2].However,the existing in vivo bioassay procedure based on somatropin-induced weight gain in rats is complicated,and the use of a rat cell line-based approach(Nb2-11 bioassay),which measures the production of adenosine triphosphate(ATP)as a direct indicator of cell growth,has a low mechanism of action(MOA)relevance.Therefore,novel rhGH bioassays are still needed.To this end,we developed a reporter gene assay(RGA)based on the GH/insulin-like growth factor-1(IGF-1)axis.展开更多
实验室安全建设是实验室高效有序运行的保障。大学生作为基础教学实验室运行的主力,他们的安全素养直接影响着实验室的安全状况。在实验教学过程中构建注重安全素养培养的“实验室管理人员、教师、学生——全员、全时三位一体实验教学...实验室安全建设是实验室高效有序运行的保障。大学生作为基础教学实验室运行的主力,他们的安全素养直接影响着实验室的安全状况。在实验教学过程中构建注重安全素养培养的“实验室管理人员、教师、学生——全员、全时三位一体实验教学模式”,并在分析化学实验教学中进行了具体实践。新的实验教学模式加强了实验室管理员、教师与学生之间的沟通,通过COOP与7S实验教学方案,使学生在学习的同时沉浸式参与实验环境维护及建设、根植安全理念。利用Partial Eta Squared(η2)检验和多元Logistic回归模型分析发现,实验过程操作规范性和操作区有序度对学生安全素养影响明显。实践证明,该模式有助于培养学生良好的实验习惯和安全素养,增加学生在实验室中的责任感和获得感,实现管教增质、教学相长、安全铸魂的教学目标,使实验室人员可以把安全时刻掌握在自己手中,实验室安全运行水平有效提升。展开更多
Organic electrodes are considered competitive candidates for the next-generation high-performance energy storage devices owing to their advantages of structural flexibility and abundant resources.However,solubility an...Organic electrodes are considered competitive candidates for the next-generation high-performance energy storage devices owing to their advantages of structural flexibility and abundant resources.However,solubility and low electronic conductivity have been major obstacles to the practical application.To address these challenges,the structural design and interfacial regulation of organic electrodes are crucial to the performance enhancement.Herein,we report on aπ-conjugated polymer cathode material of poly(3,4,9,10-perylenetetracarboxylic diimide)(PPI)for metal ion batteries,and the performance optimization is achieved by matching suitable conductive carbons and liquid electrolytes.Ultimately,the carbon nanotubes(CNTs)with weight content of 25%and 1 M NaPF6 in ethylene carbonate/diethyl carbonate electrolyte are introduced to assemble the batteries,and the discharge specific capacity,cycling stability and rate performance are enhanced effectively.The PPI-CNTjjNa battery displays high specific capacities of 146.4 and 117 mAh g^(-1) at current densities of 0.1 C and 5 C,respectively.Furthermore,PPI-CNTjjNa battery demonstrates excellent long-term cycling stability of 5000 cycles with low 0.007 mAh g^(-1)capacity decay per cycle at 1C due to the thin and uniform cathode electrolyte interphase.Moreover,the PPI-CNTjjNa battery presents good cycling stability at high temperatures of 60℃,and retains a capacity of 132.5 mAh g^(-1) after 300 cycles with a high capacity retention rate of 96.9%.Besides,PPI-CNT displays good electrochemical performance and compatibility in lithium-ion and potassium-ion batteries.This work provides an alternative optimization strategy for organic electrodes applied in long-lifetime metal ion batteries.展开更多
Carbon-based electromagnetic wave(EMW)absorbing materials attached with metal sulfides famous for good dielectric properties are favored by researchers,which can form heterogeneous interfaces and thus provide suppleme...Carbon-based electromagnetic wave(EMW)absorbing materials attached with metal sulfides famous for good dielectric properties are favored by researchers,which can form heterogeneous interfaces and thus provide supplementary loss mechanisms to make up for the deficiencies of a single material in energy attenuation.Here,Co_(9)S_(8)/Co@coral-like carbon nanofibers(CNFs)/porous carbon hybrids are successfully fabricated by hydrothermal and chemical vapor deposition.The samples have exceptional EMW absorb-ing properties,with a minimum reflection loss of-57.48 dB at a thickness of 2.94 mm and an effective absorption bandwidth of up to 6.10 GHz at only 2.20 mm.The interlocking structure formed by Co@coral-like CNFs,interfacial polarization generated by heterostructure of Co_(9)S_(8),abundant defects and large specific surface area resulted from porous properties are important factors in attaining magnetic-dielectric balance and excellent absorption performance.Different matrixes are selected instead of paraffin to investigate the effect of matrix materials on EMW absorbing capacity.Besides,the EMW attenuation potential for practical applications is also demonstrated by radar cross-section simulations,electric field intensity distribution and power loss density.This work provides a novel strategy for designing outstanding EMW absorbers with unique microstructures using facile and low-cost synthetic routes.展开更多
Wound healing in diabetic patients presents significant challenges due to heightened risks of bacterial infection,elevated glucose levels,and insufficient angiogenesis.Nanozymes are widely employed for wound healing,b...Wound healing in diabetic patients presents significant challenges due to heightened risks of bacterial infection,elevated glucose levels,and insufficient angiogenesis.Nanozymes are widely employed for wound healing,but most current nanozyme systems exhibit only moderate activity limited by incompatible reaction microenvironments including p H and hydrogen peroxide(H_(2)O_(2))concentration.Herein,a glucoseactivated nanozyme hydrogel was developed using bovine serum albumin(BSA)-modified gold nanoparticles(Au NPs)attached to a two-dimensional(2D)metal-organic framework(MOF)(Cu-TCPP(Fe)@Au@BSA)by an in situ growth method.The Au NPs function as a glucose oxidase(GOx)-like enzyme,converting glucose to gluconic acid and H_(2)O_(2),triggering the peroxidase(POD)-like activity of Cu-TCPP(Fe)to produce hydroxyl radicals(·OH),effectively eliminating bacteria.Additionally,the modification of BSA reduces the Au NP size,enhancing enzyme activity.Both in vitro and in vivo tests demonstrate that this nanozyme hydrogel can be activated by the microenvironment to lower blood glucose,eliminate bacterial infections,and promote epithelial formation and collagen deposition,thus accelerating diabetic wound healing effectively.The multifunctional nanozyme hydrogel dressing developed in this study presents a promising therapeutic approach to enhance diabetic wound healing.展开更多
The Yangchuling porphyry W-Mo deposit(YPWD),located in the Jiangnan porphyryskarn tungsten ore belt,is one of the most important and large-scale porphyry W-Mo deposits in South China.While previous zircon U-Pb and mol...The Yangchuling porphyry W-Mo deposit(YPWD),located in the Jiangnan porphyryskarn tungsten ore belt,is one of the most important and large-scale porphyry W-Mo deposits in South China.While previous zircon U-Pb and molybdenite Re-Os data suggest that Yangchuling WMo ore bodies formed almost simultaneously with granodiorite and monzogranitic porphyry at~150–144 Ma,their post emplacement history remains poorly understood,making their preservation status at depth uncertain.In this paper,new zircon and apatite(U-Th)/He and apatite fission track(ZHe,AHe and AFT,respectively)data of one hornfels and five intrusive rocks from a 1000-meter borehole are presented.These,together with new inverse thermal history models and previous geochronological data,help elucidate the post-diagenetic exhumation history and preservation status of the Yangchuling porphyry W-Mo deposit.In general,ZHe and AHe ages decrease gradually from the near surface downwards and have relatively little intra-sample variation,ranging from 133 to 73Ma and 67 to 25 Ma,respectively.All four granodiorites yield similar AFT ages that range from 63 to 55 Ma with mean track lengths varying from 12.2±0.7 to 12.6±0.5μm.Thermal history modelling indicates that the Yangchuling ore district experienced slow,monotonic cooling since the Cretaceous.Age-depth relationships are interpreted as recording~3.7±0.8 km of Cretaceous-recent exhumation in response to regional extension throughout South China thought to have been driven by subduction retreat of the Paleo-Pacific Plate.Comparison of estimated net exhumation and previous metallogenic depth of~4–5 km suggests that W-Mo ore bodies could still exist at depths of up to~1.3±0.8 km relative to Earth surface in the YPWD region.Preservation of the YPWD is attributed to the limited amount of regional denudation during the Late Cretaceous and Cenozoic.展开更多
Chronic diabetic wounds result from a disrupted microenvironment where oxidative stress,impaired angiogenesis,and persistent infection create a vicious cycle that delays healing.Unfortunately,existing treatments often...Chronic diabetic wounds result from a disrupted microenvironment where oxidative stress,impaired angiogenesis,and persistent infection create a vicious cycle that delays healing.Unfortunately,existing treatments often fail to address these interrelated issues,resulting in suboptimal healing.Here,we propose a base-tip dual-component hydrogel microneedle(MN)system(GBEVs-pVEGF/AgNPs@MNs),consisting of a tip loaded with plant-bacterial hybrid extracellular vesicles(GBEVs-pVEGF)and a base containing silver nanoparticles(AgNPs).Upon penetrating the necrotic tissue of diabetic wounds,our multifunctional MNs could effectively deliver GBEVs-pVEGF,thereby alleviating oxidative stress,promoting cell migration,and facilitating angiogenesis.Additionally,the physical barrier formed by the basal layer synergistically mitigates persistent bacterial infections during wound healing in conjunction with the antimicrobial agent AgNPs.This multifunctional MN system,integrating antioxidant,angiogenic,and antimicrobial properties,effectively restores the disrupted wound microenvironment,offering significant potential for accelerating diabetic wound healing.展开更多
The impact of aerosols on clouds,which remains one of the largest aspects of uncertainty in current weather forecasting and climate change research,can be influenced by various factors,such as the underlying surface t...The impact of aerosols on clouds,which remains one of the largest aspects of uncertainty in current weather forecasting and climate change research,can be influenced by various factors,such as the underlying surface type,cloud type,cloud phase,and aerosol type.To explore the impact of different underlying surfaces on the effect of aerosols on cloud development,this study focused on the Yangtze River Delta(YRD)and its offshore regions(YRD sea)for a comparative analysis based on multi-source satellite data,while also considering the variations in cloud type and cloud phase.The results show lower cloud-top height and depth of single-layer clouds over the ocean than land,and higher liquid cloud in spring over the ocean.Aerosols are found to enhance the cumulus cloud depth through microphysical effects,which is particularly evident over the ocean.Aerosols are also found to decrease the cloud droplet effective radius in the ocean region and during the mature stage of cloud development in the land region,while opposite results are found during the early stage of cloud development in the land region.The quantitative results indicate that the indirect effect is positive(0.05)in the land region at relatively high cloud water path,which is smaller than that in the ocean region(0.11).The findings deepen our understanding of the influence aerosols on cloud development and the mechanisms involved,which could then be applied to improve the ability to simulate cloud-associated weather processes.展开更多
Electrochemical impedance spectroscopy(EIS)offers valuable insights into the dynamic behaviors of lithium-ion batteries,making it a powerful and non-invasive tool for evaluating battery health.However,EIS falls short ...Electrochemical impedance spectroscopy(EIS)offers valuable insights into the dynamic behaviors of lithium-ion batteries,making it a powerful and non-invasive tool for evaluating battery health.However,EIS falls short in quantitatively determining the degree of specific degradation modes,which are essential for improving battery lifespan.This study introduces a novel approach employing deep neural networks enhanced by an attention mechanism to identify the degree of degradation modes.The proposed method can automatically determine the most relevant frequency ranges for each degradation mode,which can link impedance characteristics to battery degradation.To overcome the limitation of scarce labeled experimental data,simulation results derived from mechanistic models are incorporated into the model.Validation results demonstrate that the proposed method could achieve root mean square errors below 3%for estimating loss of lithium inventory and loss of active material of the positive electrode,and below 4%for estimating loss of active material of the negative electrode while requiring only 25%of early-stage experimental degradation data.By integrating simulation results,the proposed method achieves a reduction in maximum estimation error ranging from 42.92%to 66.30%across different temperatures and operating conditions compared to the baseline model trained solely on experimental data.展开更多
Bimodal pressure sensors capable of simultaneously detecting static and dynamic forces are essential to medical detection and bio-robotics.However,conventional pressure sensors typically integrate multiple operating m...Bimodal pressure sensors capable of simultaneously detecting static and dynamic forces are essential to medical detection and bio-robotics.However,conventional pressure sensors typically integrate multiple operating mechanisms to achieve bimodal detection,leading to complex device architectures and challenges in signal decoupling.In this work,we address these limitations by leveraging the unique piezotronic effect of Y-ion-doped ZnO to develop a bimodal piezotronic sensor(BPS)with a simplified structure and enhanced sensitivity.Through a combination of finite element simulations and experimental validation,we demonstrate that the BPS can effectively monitor both dynamic and static forces,achieving an on/off ratio of 1029,a gauge factor of 23,439 and a static force response duration of up to 600 s,significantly outperforming the performance of conventional piezoelectric sensors.As a proof-of-concept,the BPS demonstrates the continuous monitoring of Achilles tendon behavior under mixed dynamic and static loading conditions.Aided by deep learning algorithms,the system achieves 96%accuracy in identifying Achilles tendon movement patterns,thus enabling warnings for dangerous movements.This work provides a viable strategy for bimodal force monitoring,highlighting its potential in wearable electronics.展开更多
Acetaldehyde plays a significant role in atmospheric photochemical reactions and ozone formation.Previous studies have shown that acetaldehyde may rapidly be generated over short periods and impact ozone production,ye...Acetaldehyde plays a significant role in atmospheric photochemical reactions and ozone formation.Previous studies have shown that acetaldehyde may rapidly be generated over short periods and impact ozone production,yet the underlyingmechanism remains unclear.To better elucidate thesemechanisms,a field campaign was conducted in Dongying,a typical petrochemical city in China.The observed acetaldehyde concentration averaged 3.0±1.6 ppbv,with a peak around 09:00 local time.The diurnal variations of acetaldehyde were categorized into two types,with Category 1 exhibiting relatively high values and increasing sharply in concentration between 07:00 and 09:00 a.m.(refer to morning peak episode,MPE),and the remaining classified as Category 2.Category 1 was similar to previous studies at heavily polluted sites but differed fromcleaner locations.Using an observation-based chemical box model,we found that acetaldehyde contributed an average of 10.2%to the net ozone production rate.Combined with a positive matrix factorizationmodel,we identified secondary formation as the dominant source of acetaldehyde(45.0%),and the daytime production rate of acetaldehyde in Category 1 was significantly higher than that in Category 2.Cis-2-butene and trans-2-butene were identified as key precursors for the rapid acetaldehyde formation during the MEP,with the petroleum industry being their primary source.Volatile organic compounds(VOCs)from petroleum industry contributed over 60%to acetaldehyde formation during the morning peak.Our findings underscore the urgent need for targeted VOCs management strategies in petroleum sector tomitigate both carbonyl and ozone formation.展开更多
Net primary productivity(NPP)is the net accumulation of organic matter by vegetation through photosynthesis and serves as a key indicator for exploring vegetation responses to climate change.Considering the remote and...Net primary productivity(NPP)is the net accumulation of organic matter by vegetation through photosynthesis and serves as a key indicator for exploring vegetation responses to climate change.Considering the remote and local impacts of soil heat capacities on vegetation growth through pathways of atmospheric circulation and land–atmosphere interaction,this paper develops a statistical prediction model for NPP from April to June(AMJ)across the middle-to-high latitudes of Eurasia.The model introduces two physically meaningful predictors:the snow water equivalent(SWE)from February to March(FM)over central Europe and the FM local soil temperature(ST).The positive phase of FM SWE triggers anomalous eastward-propagating Rossby waves,leading to an anomalous low-pressure system and cooling in the middle-to-high latitudes of Eurasia.This effect persists into spring through snow feedback to the atmosphere and affects subsequent NPP changes.The ST is closely related to the AMJ temperature and precipitation.With positive ST anomalies,the AMJ temperature and precipitation exhibit an east–west dipole anomaly distribution in this region.The single-factor prediction scheme using ST as the predictor is much better than using SWE as the predictor.Independent validation results from 2009 to 2014 demonstrate that the ST scheme alone has good predictive performance for the spatial distribution and interannual variability of NPP.The predictive skills of the multi-factor prediction schemes can be improved by about 13%if the ST predictor is included.The findings confirm that local ST is a predictor that must be included for NPP prediction.展开更多
The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for ...The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for MICP technology.In this study,the uniformity of the saturated calcareous sand treated with MICP was in-vestigated through one-dimensional calcareous sand column tests and model tests.The coefficient of variation was employed in one-dimensional sand column tests to investigate the impact of injection rate,cementation solution concentration,and number of injection cycles on the uniformity of the MICP treatment.Additionally,model tests were conducted to investigate the impact of injection pressure and methods on the treatment range and uniformity under three-dimensional seepage conditions.Test results demonstrate that the reinforcement strength and uniformity are significantly influenced by the injection rate of the cementation solution,with a rate of 3 mL/min,yielding a favorable treatment effect.Excessive concentration of the cementation solution can lead to significant non-uniformity and a reduction in the compressive strength of MICP-treated samples.Conversely,excessively low concentrations may result in decreased bonding efficiency.Among the four considered con-centrations,0.5 mol/L and 1 mol/L exhibit superior reinforcing effects.The morphological development of calcareous sandy foundation reinforcement is associated with the spatial distribution pattern of the bacterial solution,exhibiting a relatively larger reinforcement area in proximity to the lower region of the model and a gradually decreasing range towards the upper part.Under three-dimensional seepage conditions,in addition to the non-uniform radial cementation along the injection pipe,there is also vertical heterogeneity of cementation along the length of the injection pipe due to gravitational effects,resulting in preferential deposition of calcium carbonate at the lower section,The application of injection pressure and a double-pipe circulation injection method can mitigate the accumulation of bacterial solution and cementation solution at the bottom,thereby improving the reinforcement range and uniformity.展开更多
Eutrophic shallow lakes are generally considered as a contributor to the emission of nitrous oxide(N_(2)O),while regional and global estimates have remained imprecise.This due to a lack of data and insufficient unders...Eutrophic shallow lakes are generally considered as a contributor to the emission of nitrous oxide(N_(2)O),while regional and global estimates have remained imprecise.This due to a lack of data and insufficient understanding of the multiple contributing factors.This study characterized the spatiotemporal variability in N_(2)O concentrations and N_(2)O diffusive fluxes and the contributing factors in LakeWuliangsuhai,a typical shallow eutrophic and seasonally frozen lake in Inner Mongolia with cold and arid climate.Dissolved N_(2)O concentrations of the lake exhibited a range of 4.5 to 101.2 nmol/L,displaying significant spatiotemporal variations.The lowest and highest concentrations were measured in summer and winter,respectively.The spatial distribution of N_(2)Ofluxwas consistent with that of N_(2)O concentrations.Additionally,the hotspots of N_(2)O emissions were detected within close to the main inflow of lake.The wide spatial and temporal variation in N_(2)O emissions indicate the complexity and its relative importance of factors influencing emissions.N_(2)O emissions in different lake zones and seasons were regulated by diverse factors.Factors influencing the spatial and temporal distribution of N_(2)O concentrations and fluxes were identified as WT,WD,DO,Chl-a,SD and COD.Interestingly,the same factor demonstrated opposing effects on N_(2)O emission in various seasons or zones.This research improves our understanding of N_(2)O emissions in shallow eutrophic lakes in cold and arid areas.展开更多
With the gradual reduction in high-quality iron ore resources,the global steel industry faces long-term challenges.For example,the continuous increase in the Al_(2)O_(3) content of iron ore has led to a decrease in th...With the gradual reduction in high-quality iron ore resources,the global steel industry faces long-term challenges.For example,the continuous increase in the Al_(2)O_(3) content of iron ore has led to a decrease in the metallurgical performance of sinter and fluctuations in slag properties.Considering calcium ferrite(CF)and composite CF(silico-ferrite of calcium and aluminum,SFCA)play a crucial role as a binding phase in high-alkalinity sinter and exhibit excellent physical strength and metallurgical performance,we propose incorporating excess Al_(2)O_(3) into SFCA to form a new binding phase with excellent properties for high-quality sinter preparation.In the synthesis of high-Al_(2)O_(3) SFCA,two high-Al_(2)O_(3) phases were identified as types A(Al_(1.2)Ca_(2.8)Fe_(8.7)O_(2)0Si_(0.8))and B(Ca_(4)Al_(4.18)Fe_(1.82)Si_(6)O_(26)).Results show that type A SFCA sample had a higher cell density(4.13 g/cm^(3))and longer Fe-O bond length(2.2193Å)than type B(3.46 g/cm^(3) and 1.9415Å),with a significantly greater lattice oxygen concentration(7.86%vs.1.85%),which demonstrates advantages in strength and reducibility.Type A SFCA sample contained a lower proportion of silicates,was predominantly composed of SFCA,and exhibited minimal porosity.Melting point and viscosity simulation tests indicate that type A SFCA sample formed a liquid phase at 880°C with a viscosity range of 0-0.35 Pa·s,which is notably lower than that of type B SFCA sample(1220°C and 0-20 Pa·s).This finding suggests that type A SFCA sample has a low initial melting temperature and viscosity,which facilitates increasing liquid-phase generation and improving flow properties.Such a condition enhances the adhesion to surrounding ore particles.Compressive strength tests reveal that type A SFCA sample(36.83-42.48 MPa)considerably outperformed type B SFCA sample(5.98-12.79 MPa)and traditional sinter(5.02-13.68 MPa).In addition,at 900°C,type A SFCA sample achieved a final reducibility of 0.89,which surpassed that of type B SFCA sample(0.83).In summary,type A SFCA sample demonstrates superior structural,thermophysical,and metallurgical properties,which highlights its promising potential for industrial applications.展开更多
文摘Alzheimer's disease,a progressively degenerative neurological disorder,is the most common cause of dementia in the elderly.While its precise etiology remains unclear,researchers have identified diverse pathological characteristics and molecular pathways associated with its progression.Advances in scientific research have increasingly highlighted the crucial role of non-coding RNAs in the progression of Alzheimer's disease.These non-coding RNAs regulate several biological processes critical to the advancement of the disease,offering promising potential as therapeutic targets and diagnostic biomarkers.Therefore,this review aims to investigate the underlying mechanisms of Alzheimer's disease onset,with a particular focus on microRNAs,long non-coding RNAs,and circular RNAs associated with the disease.The review elucidates the potential pathogenic processes of Alzheimer's disease and provides a detailed description of the synthesis mechanisms of the three aforementioned non-coding RNAs.It comprehensively summarizes the various non-coding RNAs that have been identified to play key regulatory roles in Alzheimer's disease,as well as how these noncoding RNAs influence the disease's progression by regulating gene expression and protein functions.For example,miR-9 targets the UBE4B gene,promoting autophagy-mediated degradation of Tau protein,thereby reducing Tau accumulation and delaying Alzheimer's disease progression.Conversely,the long non-coding RNA BACE1-AS stabilizes BACE1 mRNA,promoting the generation of amyloid-βand accelerating Alzheimer's disease development.Additionally,circular RNAs play significant roles in regulating neuroinflammatory responses.By integrating insights from these regulatory mechanisms,there is potential to discover new therapeutic targets and potential biomarkers for early detection and management of Alzheimer's disease.This review aims to enhance the understanding of the relationship between Alzheimer's disease and non-coding RNAs,potentially paving the way for early detection and novel treatment strategies.
基金supported by the National Key R&D Program of China(grant No.2023YFA1608304 and No.2023YFA1608300)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0550100 and XDB0550000)the National Natural Science Foundation of China(NSFC,grant Nos.12090041,12090040,11903054,12422303,and 12261141690)。
文摘The Si Tian project,designed to utilize 60 telescopes distributed across multiple sites in China,is a next-generation timedomain survey initiative.As a pathfinder for the Si Tian project,the Mini-Si Tian(MST)has been proposed and implemented to test the Si Tian’s brain and data pipeline,and to evaluate the feasibility of its technology and science cases.Mounted at the Xinglong Observatory,the MST project comprises three 30 cm telescopes and has been operated since 2022 November.Each telescope of the MST possesses a large field of view,covering 2°.29×1°.53 FOV,and is equipped withg',r'andi'filters,respectively.Acting as the pioneer of the forthcoming Si Tian project,the MST is dedicated to the discovery of variable stars,transients,and outburst events,and has already obtained some interesting scientific results.In this paper,we will summarize the first-two-year operation of the MST project.
基金supported by the Beijing Natural Science Foundation(Grant No.L223013)。
文摘For the diagnostics and health management of lithium-ion batteries,numerous models have been developed to understand their degradation characteristics.These models typically fall into two categories:data-driven models and physical models,each offering unique advantages but also facing limitations.Physics-informed neural networks(PINNs)provide a robust framework to integrate data-driven models with physical principles,ensuring consistency with underlying physics while enabling generalization across diverse operational conditions.This study introduces a PINN-based approach to reconstruct open circuit voltage(OCV)curves and estimate key ageing parameters at both the cell and electrode levels.These parameters include available capacity,electrode capacities,and lithium inventory capacity.The proposed method integrates OCV reconstruction models as functional components into convolutional neural networks(CNNs)and is validated using a public dataset.The results reveal that the estimated ageing parameters closely align with those obtained through offline OCV tests,with errors in reconstructed OCV curves remaining within 15 mV.This demonstrates the ability of the method to deliver fast and accurate degradation diagnostics at the electrode level,advancing the potential for precise and efficient battery health management.
基金supported by the first batch of grants from the State Key Laboratory of Drug Regulatory Science,China(Grant No.:2023SKLDRS0108).
文摘Recombinant human growth hormone(rhGH)has been widely used for the treatment of disorders associated with GH deficiency and multiple clinical indications[1].Accurate determination of biological activity is essential in the development,registration,and quality control of rhGH pharmaceutical products[2].However,the existing in vivo bioassay procedure based on somatropin-induced weight gain in rats is complicated,and the use of a rat cell line-based approach(Nb2-11 bioassay),which measures the production of adenosine triphosphate(ATP)as a direct indicator of cell growth,has a low mechanism of action(MOA)relevance.Therefore,novel rhGH bioassays are still needed.To this end,we developed a reporter gene assay(RGA)based on the GH/insulin-like growth factor-1(IGF-1)axis.
文摘实验室安全建设是实验室高效有序运行的保障。大学生作为基础教学实验室运行的主力,他们的安全素养直接影响着实验室的安全状况。在实验教学过程中构建注重安全素养培养的“实验室管理人员、教师、学生——全员、全时三位一体实验教学模式”,并在分析化学实验教学中进行了具体实践。新的实验教学模式加强了实验室管理员、教师与学生之间的沟通,通过COOP与7S实验教学方案,使学生在学习的同时沉浸式参与实验环境维护及建设、根植安全理念。利用Partial Eta Squared(η2)检验和多元Logistic回归模型分析发现,实验过程操作规范性和操作区有序度对学生安全素养影响明显。实践证明,该模式有助于培养学生良好的实验习惯和安全素养,增加学生在实验室中的责任感和获得感,实现管教增质、教学相长、安全铸魂的教学目标,使实验室人员可以把安全时刻掌握在自己手中,实验室安全运行水平有效提升。
基金supported by Open Foundation of Shanghai Jiao Tong University Shaoxing Research Institute of Renewable Energy and Molecular Engineering(Grant No.JDSX2023008)Joint Fund of Scientific and Technological Research and Development Program of Henan Province(222301420009)the funding of Zhengzhou University.
文摘Organic electrodes are considered competitive candidates for the next-generation high-performance energy storage devices owing to their advantages of structural flexibility and abundant resources.However,solubility and low electronic conductivity have been major obstacles to the practical application.To address these challenges,the structural design and interfacial regulation of organic electrodes are crucial to the performance enhancement.Herein,we report on aπ-conjugated polymer cathode material of poly(3,4,9,10-perylenetetracarboxylic diimide)(PPI)for metal ion batteries,and the performance optimization is achieved by matching suitable conductive carbons and liquid electrolytes.Ultimately,the carbon nanotubes(CNTs)with weight content of 25%and 1 M NaPF6 in ethylene carbonate/diethyl carbonate electrolyte are introduced to assemble the batteries,and the discharge specific capacity,cycling stability and rate performance are enhanced effectively.The PPI-CNTjjNa battery displays high specific capacities of 146.4 and 117 mAh g^(-1) at current densities of 0.1 C and 5 C,respectively.Furthermore,PPI-CNTjjNa battery demonstrates excellent long-term cycling stability of 5000 cycles with low 0.007 mAh g^(-1)capacity decay per cycle at 1C due to the thin and uniform cathode electrolyte interphase.Moreover,the PPI-CNTjjNa battery presents good cycling stability at high temperatures of 60℃,and retains a capacity of 132.5 mAh g^(-1) after 300 cycles with a high capacity retention rate of 96.9%.Besides,PPI-CNT displays good electrochemical performance and compatibility in lithium-ion and potassium-ion batteries.This work provides an alternative optimization strategy for organic electrodes applied in long-lifetime metal ion batteries.
基金financially supported by the Natural Science Foundation of Shandong Province(Nos.ZR2021ME194,2022TSGC2448,and 2023TSGC0545)the Key Technology Research and Development Program of Shandong Province(No.2021ZLGX01).
文摘Carbon-based electromagnetic wave(EMW)absorbing materials attached with metal sulfides famous for good dielectric properties are favored by researchers,which can form heterogeneous interfaces and thus provide supplementary loss mechanisms to make up for the deficiencies of a single material in energy attenuation.Here,Co_(9)S_(8)/Co@coral-like carbon nanofibers(CNFs)/porous carbon hybrids are successfully fabricated by hydrothermal and chemical vapor deposition.The samples have exceptional EMW absorb-ing properties,with a minimum reflection loss of-57.48 dB at a thickness of 2.94 mm and an effective absorption bandwidth of up to 6.10 GHz at only 2.20 mm.The interlocking structure formed by Co@coral-like CNFs,interfacial polarization generated by heterostructure of Co_(9)S_(8),abundant defects and large specific surface area resulted from porous properties are important factors in attaining magnetic-dielectric balance and excellent absorption performance.Different matrixes are selected instead of paraffin to investigate the effect of matrix materials on EMW absorbing capacity.Besides,the EMW attenuation potential for practical applications is also demonstrated by radar cross-section simulations,electric field intensity distribution and power loss density.This work provides a novel strategy for designing outstanding EMW absorbers with unique microstructures using facile and low-cost synthetic routes.
基金supported by the National Natural Science Foundation of China Project(No.22208321)the China Postdoctoral Science Foundation Project(No.2022M720130)+1 种基金the Key Scientific Research Project of Henan Province High Education Institutions(No.24A350018)the Natural Science Foundation of Henan Province-Outstanding Youth Foundation(No.232300421058)。
文摘Wound healing in diabetic patients presents significant challenges due to heightened risks of bacterial infection,elevated glucose levels,and insufficient angiogenesis.Nanozymes are widely employed for wound healing,but most current nanozyme systems exhibit only moderate activity limited by incompatible reaction microenvironments including p H and hydrogen peroxide(H_(2)O_(2))concentration.Herein,a glucoseactivated nanozyme hydrogel was developed using bovine serum albumin(BSA)-modified gold nanoparticles(Au NPs)attached to a two-dimensional(2D)metal-organic framework(MOF)(Cu-TCPP(Fe)@Au@BSA)by an in situ growth method.The Au NPs function as a glucose oxidase(GOx)-like enzyme,converting glucose to gluconic acid and H_(2)O_(2),triggering the peroxidase(POD)-like activity of Cu-TCPP(Fe)to produce hydroxyl radicals(·OH),effectively eliminating bacteria.Additionally,the modification of BSA reduces the Au NP size,enhancing enzyme activity.Both in vitro and in vivo tests demonstrate that this nanozyme hydrogel can be activated by the microenvironment to lower blood glucose,eliminate bacterial infections,and promote epithelial formation and collagen deposition,thus accelerating diabetic wound healing effectively.The multifunctional nanozyme hydrogel dressing developed in this study presents a promising therapeutic approach to enhance diabetic wound healing.
基金supported by the National Natural Science Foundation of China(Nos.42162013,42002095)the Foundation of State Key Laboratory of Nuclear Resources and Environment(Nos.2022NRE34,NRE2021-01)+1 种基金Jiangxi Provincial Natural Science Foundation(Nos.20242BAB26048,20242BAB25178)Fund of National Key Laboratory of Science and Technology on Remote Sensing Information and imagery Analysis,Beijing Research Institute of Uranium Geology(No.6142A01210405)。
文摘The Yangchuling porphyry W-Mo deposit(YPWD),located in the Jiangnan porphyryskarn tungsten ore belt,is one of the most important and large-scale porphyry W-Mo deposits in South China.While previous zircon U-Pb and molybdenite Re-Os data suggest that Yangchuling WMo ore bodies formed almost simultaneously with granodiorite and monzogranitic porphyry at~150–144 Ma,their post emplacement history remains poorly understood,making their preservation status at depth uncertain.In this paper,new zircon and apatite(U-Th)/He and apatite fission track(ZHe,AHe and AFT,respectively)data of one hornfels and five intrusive rocks from a 1000-meter borehole are presented.These,together with new inverse thermal history models and previous geochronological data,help elucidate the post-diagenetic exhumation history and preservation status of the Yangchuling porphyry W-Mo deposit.In general,ZHe and AHe ages decrease gradually from the near surface downwards and have relatively little intra-sample variation,ranging from 133 to 73Ma and 67 to 25 Ma,respectively.All four granodiorites yield similar AFT ages that range from 63 to 55 Ma with mean track lengths varying from 12.2±0.7 to 12.6±0.5μm.Thermal history modelling indicates that the Yangchuling ore district experienced slow,monotonic cooling since the Cretaceous.Age-depth relationships are interpreted as recording~3.7±0.8 km of Cretaceous-recent exhumation in response to regional extension throughout South China thought to have been driven by subduction retreat of the Paleo-Pacific Plate.Comparison of estimated net exhumation and previous metallogenic depth of~4–5 km suggests that W-Mo ore bodies could still exist at depths of up to~1.3±0.8 km relative to Earth surface in the YPWD region.Preservation of the YPWD is attributed to the limited amount of regional denudation during the Late Cretaceous and Cenozoic.
基金support from the National Natural Science Foundation of China(No.82472444).
文摘Chronic diabetic wounds result from a disrupted microenvironment where oxidative stress,impaired angiogenesis,and persistent infection create a vicious cycle that delays healing.Unfortunately,existing treatments often fail to address these interrelated issues,resulting in suboptimal healing.Here,we propose a base-tip dual-component hydrogel microneedle(MN)system(GBEVs-pVEGF/AgNPs@MNs),consisting of a tip loaded with plant-bacterial hybrid extracellular vesicles(GBEVs-pVEGF)and a base containing silver nanoparticles(AgNPs).Upon penetrating the necrotic tissue of diabetic wounds,our multifunctional MNs could effectively deliver GBEVs-pVEGF,thereby alleviating oxidative stress,promoting cell migration,and facilitating angiogenesis.Additionally,the physical barrier formed by the basal layer synergistically mitigates persistent bacterial infections during wound healing in conjunction with the antimicrobial agent AgNPs.This multifunctional MN system,integrating antioxidant,angiogenic,and antimicrobial properties,effectively restores the disrupted wound microenvironment,offering significant potential for accelerating diabetic wound healing.
基金supported by the National Natural Science Foundation of China(Grant No.42230601).
文摘The impact of aerosols on clouds,which remains one of the largest aspects of uncertainty in current weather forecasting and climate change research,can be influenced by various factors,such as the underlying surface type,cloud type,cloud phase,and aerosol type.To explore the impact of different underlying surfaces on the effect of aerosols on cloud development,this study focused on the Yangtze River Delta(YRD)and its offshore regions(YRD sea)for a comparative analysis based on multi-source satellite data,while also considering the variations in cloud type and cloud phase.The results show lower cloud-top height and depth of single-layer clouds over the ocean than land,and higher liquid cloud in spring over the ocean.Aerosols are found to enhance the cumulus cloud depth through microphysical effects,which is particularly evident over the ocean.Aerosols are also found to decrease the cloud droplet effective radius in the ocean region and during the mature stage of cloud development in the land region,while opposite results are found during the early stage of cloud development in the land region.The quantitative results indicate that the indirect effect is positive(0.05)in the land region at relatively high cloud water path,which is smaller than that in the ocean region(0.11).The findings deepen our understanding of the influence aerosols on cloud development and the mechanisms involved,which could then be applied to improve the ability to simulate cloud-associated weather processes.
基金supported by the National Key R&D Program of China(2024YFB2505003).
文摘Electrochemical impedance spectroscopy(EIS)offers valuable insights into the dynamic behaviors of lithium-ion batteries,making it a powerful and non-invasive tool for evaluating battery health.However,EIS falls short in quantitatively determining the degree of specific degradation modes,which are essential for improving battery lifespan.This study introduces a novel approach employing deep neural networks enhanced by an attention mechanism to identify the degree of degradation modes.The proposed method can automatically determine the most relevant frequency ranges for each degradation mode,which can link impedance characteristics to battery degradation.To overcome the limitation of scarce labeled experimental data,simulation results derived from mechanistic models are incorporated into the model.Validation results demonstrate that the proposed method could achieve root mean square errors below 3%for estimating loss of lithium inventory and loss of active material of the positive electrode,and below 4%for estimating loss of active material of the negative electrode while requiring only 25%of early-stage experimental degradation data.By integrating simulation results,the proposed method achieves a reduction in maximum estimation error ranging from 42.92%to 66.30%across different temperatures and operating conditions compared to the baseline model trained solely on experimental data.
基金financially supported by the National Natural Science Foundation of China(No.U2330120)the Natural Science Foundation of Sichuan Province of China(No.2023NSFSC0313)the Basic Research Cultivation Project of Southwest Jiaotong University(No.2682023KJ024)。
文摘Bimodal pressure sensors capable of simultaneously detecting static and dynamic forces are essential to medical detection and bio-robotics.However,conventional pressure sensors typically integrate multiple operating mechanisms to achieve bimodal detection,leading to complex device architectures and challenges in signal decoupling.In this work,we address these limitations by leveraging the unique piezotronic effect of Y-ion-doped ZnO to develop a bimodal piezotronic sensor(BPS)with a simplified structure and enhanced sensitivity.Through a combination of finite element simulations and experimental validation,we demonstrate that the BPS can effectively monitor both dynamic and static forces,achieving an on/off ratio of 1029,a gauge factor of 23,439 and a static force response duration of up to 600 s,significantly outperforming the performance of conventional piezoelectric sensors.As a proof-of-concept,the BPS demonstrates the continuous monitoring of Achilles tendon behavior under mixed dynamic and static loading conditions.Aided by deep learning algorithms,the system achieves 96%accuracy in identifying Achilles tendon movement patterns,thus enabling warnings for dangerous movements.This work provides a viable strategy for bimodal force monitoring,highlighting its potential in wearable electronics.
基金supported by the National Key Research and Development Program of the Ministry of Science of Technology of China(No.2022YFC3701101)the National Natural Science Foundation of China(No.42105106)+2 种基金China Postdoctoral Science Foundation(No.2021M691921)the Ministry of Ecology and Environment of the People’s Republic of China(No.DQGG202121)Dongying Ecological and Environmental Bureau(No.2021DFKY-0779).
文摘Acetaldehyde plays a significant role in atmospheric photochemical reactions and ozone formation.Previous studies have shown that acetaldehyde may rapidly be generated over short periods and impact ozone production,yet the underlyingmechanism remains unclear.To better elucidate thesemechanisms,a field campaign was conducted in Dongying,a typical petrochemical city in China.The observed acetaldehyde concentration averaged 3.0±1.6 ppbv,with a peak around 09:00 local time.The diurnal variations of acetaldehyde were categorized into two types,with Category 1 exhibiting relatively high values and increasing sharply in concentration between 07:00 and 09:00 a.m.(refer to morning peak episode,MPE),and the remaining classified as Category 2.Category 1 was similar to previous studies at heavily polluted sites but differed fromcleaner locations.Using an observation-based chemical box model,we found that acetaldehyde contributed an average of 10.2%to the net ozone production rate.Combined with a positive matrix factorizationmodel,we identified secondary formation as the dominant source of acetaldehyde(45.0%),and the daytime production rate of acetaldehyde in Category 1 was significantly higher than that in Category 2.Cis-2-butene and trans-2-butene were identified as key precursors for the rapid acetaldehyde formation during the MEP,with the petroleum industry being their primary source.Volatile organic compounds(VOCs)from petroleum industry contributed over 60%to acetaldehyde formation during the morning peak.Our findings underscore the urgent need for targeted VOCs management strategies in petroleum sector tomitigate both carbonyl and ozone formation.
基金funded by the National Natural Science Foundation of China[grant numbers 42075115 and 41991285]the Joint Open Project of KLME&CIC-FEMD[grant number KLME201901]。
文摘Net primary productivity(NPP)is the net accumulation of organic matter by vegetation through photosynthesis and serves as a key indicator for exploring vegetation responses to climate change.Considering the remote and local impacts of soil heat capacities on vegetation growth through pathways of atmospheric circulation and land–atmosphere interaction,this paper develops a statistical prediction model for NPP from April to June(AMJ)across the middle-to-high latitudes of Eurasia.The model introduces two physically meaningful predictors:the snow water equivalent(SWE)from February to March(FM)over central Europe and the FM local soil temperature(ST).The positive phase of FM SWE triggers anomalous eastward-propagating Rossby waves,leading to an anomalous low-pressure system and cooling in the middle-to-high latitudes of Eurasia.This effect persists into spring through snow feedback to the atmosphere and affects subsequent NPP changes.The ST is closely related to the AMJ temperature and precipitation.With positive ST anomalies,the AMJ temperature and precipitation exhibit an east–west dipole anomaly distribution in this region.The single-factor prediction scheme using ST as the predictor is much better than using SWE as the predictor.Independent validation results from 2009 to 2014 demonstrate that the ST scheme alone has good predictive performance for the spatial distribution and interannual variability of NPP.The predictive skills of the multi-factor prediction schemes can be improved by about 13%if the ST predictor is included.The findings confirm that local ST is a predictor that must be included for NPP prediction.
基金support of Natural Science Foundation of China(Grant No.52108324,No.52008207,and No.52108298)for conducting this study.
文摘The mineralization process of microbial-induced calcium carbonate precipitation(MICP)is influenced by many factors,and the uniformity of the calcium carbonate precipitation has become the main focus and challenge for MICP technology.In this study,the uniformity of the saturated calcareous sand treated with MICP was in-vestigated through one-dimensional calcareous sand column tests and model tests.The coefficient of variation was employed in one-dimensional sand column tests to investigate the impact of injection rate,cementation solution concentration,and number of injection cycles on the uniformity of the MICP treatment.Additionally,model tests were conducted to investigate the impact of injection pressure and methods on the treatment range and uniformity under three-dimensional seepage conditions.Test results demonstrate that the reinforcement strength and uniformity are significantly influenced by the injection rate of the cementation solution,with a rate of 3 mL/min,yielding a favorable treatment effect.Excessive concentration of the cementation solution can lead to significant non-uniformity and a reduction in the compressive strength of MICP-treated samples.Conversely,excessively low concentrations may result in decreased bonding efficiency.Among the four considered con-centrations,0.5 mol/L and 1 mol/L exhibit superior reinforcing effects.The morphological development of calcareous sandy foundation reinforcement is associated with the spatial distribution pattern of the bacterial solution,exhibiting a relatively larger reinforcement area in proximity to the lower region of the model and a gradually decreasing range towards the upper part.Under three-dimensional seepage conditions,in addition to the non-uniform radial cementation along the injection pipe,there is also vertical heterogeneity of cementation along the length of the injection pipe due to gravitational effects,resulting in preferential deposition of calcium carbonate at the lower section,The application of injection pressure and a double-pipe circulation injection method can mitigate the accumulation of bacterial solution and cementation solution at the bottom,thereby improving the reinforcement range and uniformity.
基金supported by the National Natural Science Foundation of China(Nos.52260028,52060022,52260029,and 52160021)the National Key Research and Development Program of China(Nos.2017YFE0114800 and 2019YFC0409200)+1 种基金Inner Mongolia Autonomous Region Science and Technology Plan(No.2021GG0089)personal grant to Guohua Li by China Scholarship Council(CSC).
文摘Eutrophic shallow lakes are generally considered as a contributor to the emission of nitrous oxide(N_(2)O),while regional and global estimates have remained imprecise.This due to a lack of data and insufficient understanding of the multiple contributing factors.This study characterized the spatiotemporal variability in N_(2)O concentrations and N_(2)O diffusive fluxes and the contributing factors in LakeWuliangsuhai,a typical shallow eutrophic and seasonally frozen lake in Inner Mongolia with cold and arid climate.Dissolved N_(2)O concentrations of the lake exhibited a range of 4.5 to 101.2 nmol/L,displaying significant spatiotemporal variations.The lowest and highest concentrations were measured in summer and winter,respectively.The spatial distribution of N_(2)Ofluxwas consistent with that of N_(2)O concentrations.Additionally,the hotspots of N_(2)O emissions were detected within close to the main inflow of lake.The wide spatial and temporal variation in N_(2)O emissions indicate the complexity and its relative importance of factors influencing emissions.N_(2)O emissions in different lake zones and seasons were regulated by diverse factors.Factors influencing the spatial and temporal distribution of N_(2)O concentrations and fluxes were identified as WT,WD,DO,Chl-a,SD and COD.Interestingly,the same factor demonstrated opposing effects on N_(2)O emission in various seasons or zones.This research improves our understanding of N_(2)O emissions in shallow eutrophic lakes in cold and arid areas.
基金financially supported by the National Natural Science Foundation of China(Nos.52204331 and 52374315)the Major Industrial Innovation Plan of the Anhui Provincial Development and Reform Commission,China(No.AHZDCYCX-LSDT2023-01).
文摘With the gradual reduction in high-quality iron ore resources,the global steel industry faces long-term challenges.For example,the continuous increase in the Al_(2)O_(3) content of iron ore has led to a decrease in the metallurgical performance of sinter and fluctuations in slag properties.Considering calcium ferrite(CF)and composite CF(silico-ferrite of calcium and aluminum,SFCA)play a crucial role as a binding phase in high-alkalinity sinter and exhibit excellent physical strength and metallurgical performance,we propose incorporating excess Al_(2)O_(3) into SFCA to form a new binding phase with excellent properties for high-quality sinter preparation.In the synthesis of high-Al_(2)O_(3) SFCA,two high-Al_(2)O_(3) phases were identified as types A(Al_(1.2)Ca_(2.8)Fe_(8.7)O_(2)0Si_(0.8))and B(Ca_(4)Al_(4.18)Fe_(1.82)Si_(6)O_(26)).Results show that type A SFCA sample had a higher cell density(4.13 g/cm^(3))and longer Fe-O bond length(2.2193Å)than type B(3.46 g/cm^(3) and 1.9415Å),with a significantly greater lattice oxygen concentration(7.86%vs.1.85%),which demonstrates advantages in strength and reducibility.Type A SFCA sample contained a lower proportion of silicates,was predominantly composed of SFCA,and exhibited minimal porosity.Melting point and viscosity simulation tests indicate that type A SFCA sample formed a liquid phase at 880°C with a viscosity range of 0-0.35 Pa·s,which is notably lower than that of type B SFCA sample(1220°C and 0-20 Pa·s).This finding suggests that type A SFCA sample has a low initial melting temperature and viscosity,which facilitates increasing liquid-phase generation and improving flow properties.Such a condition enhances the adhesion to surrounding ore particles.Compressive strength tests reveal that type A SFCA sample(36.83-42.48 MPa)considerably outperformed type B SFCA sample(5.98-12.79 MPa)and traditional sinter(5.02-13.68 MPa).In addition,at 900°C,type A SFCA sample achieved a final reducibility of 0.89,which surpassed that of type B SFCA sample(0.83).In summary,type A SFCA sample demonstrates superior structural,thermophysical,and metallurgical properties,which highlights its promising potential for industrial applications.