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
In this paper,we consider the fourth-order parabolic equation with p(x)Laplacian and variable exponent source ut+∆^(2)u−div(|■u|^(p(x)−2■u))=|u|^(q(x))−1u.By applying potential well method,we obtain global existence...In this paper,we consider the fourth-order parabolic equation with p(x)Laplacian and variable exponent source ut+∆^(2)u−div(|■u|^(p(x)−2■u))=|u|^(q(x))−1u.By applying potential well method,we obtain global existence,asymptotic behavior and blow-up of solutions with initial energy J(u_(0))≤d.Moreover,we estimate the upper bound of the blow-up time for J(u_(0))≤0.展开更多
The development of materials with excellent microwave absorption(MWA)and electromagnetic interference(EMI)shielding performances has currently received attention.Herein,mesophase pitch-based carbon foam(MPCF)with 3D i...The development of materials with excellent microwave absorption(MWA)and electromagnetic interference(EMI)shielding performances has currently received attention.Herein,mesophase pitch-based carbon foam(MPCF)with 3D interconnected pore structure was prepared through the high pressure pyrolysis of mesophase coal tar pitch.It is found that the 3D interconnected cellular pores of MPCF facilitate multiple reflections of electromagnetic waves,which results in the minimum reflection loss(RLmin)value of MPCF reaches-37.84 dB with the effective absorption bandwidth(EAB)of 5.44 GHz at a thickness of 2.70 mm,and the total average electromagnetic shielding effectiveness(SE_(T))under 3.00 mm thickness achieves 26.52 dB in X-band.Subsequently,MPCF is activated by KOH to obtain activated carbon foam(A-MPCF).The average SE_(T)of A-MPCF achieves 103.00 dB for abundant nanopores on the pore cell walls,which leads to a transition from the multiple reflections of electromagnetic waves on the walls to diffuse reflection.Unfortunately,the reflection coefficient(R)of A-MPCF increases from 0.78 to 0.90.To reduce the R value,Fe_(3)O_(4)/A-MPCF was fabricated via the in situ growth of nano Fe_(3)O_(4)on A-MPCF.Consequently,the R value of Fe_(3)O_(4)/A-MPCF was reduced from 0.90 to 0.74,whereas the MWA performance was only slightly decreased.This work proposes a simple strategy for simultaneously adjusting MWA and EMI shielding performances of materials.展开更多
To evaluate their performance,we constructed organic solar cells using PTB7/Y6 and PTB7-b-PNDI active layers,which were deposited on PET substrates coated with PEDOT:PSS.The ternary solar cells demonstrated an excelle...To evaluate their performance,we constructed organic solar cells using PTB7/Y6 and PTB7-b-PNDI active layers,which were deposited on PET substrates coated with PEDOT:PSS.The ternary solar cells demonstrated an excellent power conversion efficiency after being stretched by 38%.The stretchable organic solar cells were spin-coated on the flexible substrate.The electrodes were formed via liquid metal dropcoating.Solar cell devices based on PET/PH1000/PEDOT:PSS and PTB7:Y6:5% BCP active layer materials show better stretchability than the normal solar cells.The PTB7:Y6:5% BCP-based stretchable organic solar cell achieves a high PCE of 12.3%,and a PCE of 7.8% after stretching.Incorporating block copolymer additives improves the mechanical properties of organic solar cells,thereby enabling superior stretchability.展开更多
According to the characteristics of mpox transmission,we establish a class of S1S2EIQR mpox infectious disease models with individual consciousness influence,and obtain the basic reproduction number of the model by us...According to the characteristics of mpox transmission,we establish a class of S1S2EIQR mpox infectious disease models with individual consciousness influence,and obtain the basic reproduction number of the model by using the next generation matrix method.The existence of the endemic equilibrium is demonstrated,and the global asymptotic stability of the disease-free equilibrium is obtained when R0≤1.When R0>1,the disease-free equilibrium is unstable and the endemic equilibrium is globally asymptotically stable.The data of mpox cases from Beijing are collected to simulating the epidemic trends of mpox in the next few months.The results show that increasing the isolation ratio of infected patients,increasing the cure rate of infected patients,and increasing the rate of unconscious to conscious transfer could reduce the cumulative number of mpox infections.展开更多
Low-dimensional(LD)halide perovskites have attracted considerable attention due to their distinctive structures and exceptional optoelectronic properties,including high absorption coefficients,extended charge carrier ...Low-dimensional(LD)halide perovskites have attracted considerable attention due to their distinctive structures and exceptional optoelectronic properties,including high absorption coefficients,extended charge carrier diffusion lengths,suppressed non-radiative recombination rates,and intense photoluminescence.A key advantage of LD perovskites is the tunability of their optical and electronic properties through the precise optimization of their structural arrangements and dimensionality.This review systematically examines recent progress in the synthesis and optoelectronic characterizations of LD perovskites,focusing on their structural,optical,and photophysical properties that underpin their versatility in diverse applications.The review further summarizes advancements in LD perovskite-based devices,including resistive memory,artificial synapses,photodetectors,light-emitting diodes,and solar cells.Finally,the challenges associated with stability,scalability,and integration,as well as future prospects,are discussed,emphasizing the potential of LD perovskites to drive breakthroughs in device efficiency and industrial applicability.展开更多
In this study,with the aim of achieving a high signal-to-noise ratio(SNR)in an electron-bombarded complementary metal-oxide-semiconductor(EBCMOS)imaging chip,we analyzed the sources of noise using principles from low-...In this study,with the aim of achieving a high signal-to-noise ratio(SNR)in an electron-bombarded complementary metal-oxide-semiconductor(EBCMOS)imaging chip,we analyzed the sources of noise using principles from low-light-level imaging and semiconductor theory,and established a physical computational model that relates the electron-multiplication layer to the noise characteristics of an EBCMOS chip in a uniformly doped structure with a P-type substrate.We conducted theoretical calculations to analyze the effects on noise characteristics of the passivation layer material and thickness,P-substrate doping concentration,P-substrate thickness,incident electron energy,and substrate temperature.By comparing the characteristics of pixel noise,dark current,multiplication electron numbers,and SNR under various structures,we simulated optimized structural parameters of the device.Our simulation results showed that the noise characteristics of the device could be optimized using an Al_(2)O_(3)passivation thickness of 15 nm and substrate temperature of 260 K,and by decreasing the doping concentration and thickness of the P-type substrate and increasing the incident electron energy.The optimized SNR were 252 e/e.And the substantial impact of dark current noise,primarily governed by interfacial defects,on the overall noise characteristics of the device.This research offers theoretical support to develop EBCMOS imaging chips with high gain and SNR.展开更多
Using a recognition model of atmospheric gravity waves(AGWs),we identified 519 AGW events from the OH airglow images observed at the Dandong and Lhasa stations from 2015 to 2017.The 317 AGW events detected at the Dand...Using a recognition model of atmospheric gravity waves(AGWs),we identified 519 AGW events from the OH airglow images observed at the Dandong and Lhasa stations from 2015 to 2017.The 317 AGW events detected at the Dandong station have wavelengths ranging from 30 to 60 km,periods from 14 to 20 min,horizontal speeds from 30 to 60 m/s,and relative intensities from 0.4%to 0.6%,respectively.The parameters of 202 events recorded at the Lhasa station mainly vary within 15-35 km in horizontal wavelength,4-6 min in period,40-100 m/s in horizontal velocity,and 0.1%-0.3%in relative intensity.The occurrence rate peaks in winter and summer at Dandong and the peak in summer are absent at Lhasa because of the lack of convective weather.The seasonal propagation directions of the waves are influenced by both the wind field-filtering effect and the distribution of wave sources.In spring,because of the southeastward background wind field,fewer southeastward events are observed at the Dandong station.The situation at the Lhasa station is similar.In summer,both the Lhasa and Dandong stations are dominated by northeastward AGWs,which can be attributed to the southwestward wind.In autumn,ray-tracing results show that the events at Dandong mainly originate from wind shear,whereas the events at the Lhasa station are triggered by convective weather.The location of the wave sources determines the trend of the propagation directions at the Dandong and Lhasa stations in autumn.In winter,because of the eastward wind,more events are propagating to the southwest at the Dandong station.展开更多
This study addresses the energy-intensive challenge of small-scale biogas upgrading by optimizing a chemical absorption process employing methyl diethanolamine(MDEA).Focusing on a typical distributed application of 30...This study addresses the energy-intensive challenge of small-scale biogas upgrading by optimizing a chemical absorption process employing methyl diethanolamine(MDEA).Focusing on a typical distributed application of 300 Nm^(3)/d,we developed an integrated simulation-optimization framework using Aspen HYSYS 14.0 to systematically evaluate the effects of critical operating parameters—absorption pressure,MDEA concentration,flow rate,temperature,number of trays,and reboiler duty—on methane purity and energy consumption.The key finding is the identification of an optimal parameter set:absorption pressure of 1200 kPa,MDEA concentration of 20mol%,lean flow rate of 2.5 kmol/h,temperature of 298.15 K,20 absorber trays,10 regenerator trays,and a reboiler duty of 4 kW,which enabled the product gas to achieve a high CH4 concentration of 97mol%,compliant with pipeline standards.A detailed energy consumption analysis revealed that the reboiler is the most energy-intensive unit,accounting for 75.40%of the total 5.29 kW energy consumption,followed by the gas compressor(23.38%).The specific energy consumption for CH4 recovery and the Energy Consumption Index(ECI)were quantified at 0.8852 kWh/kg CH_(4)and 6.82,respectively.This work provides a validated optimization strategy and critical energy breakdown,offering practical guidance for enhancing the technical and economic viability of small-scale,centralized biogas purification systems.展开更多
A design idea for single-component metamaterial plates is proposed to achieve the thermal stability of flexural wave bandgap by the perforated and pre-curved patterns.The band structure analysis suggests that perforat...A design idea for single-component metamaterial plates is proposed to achieve the thermal stability of flexural wave bandgap by the perforated and pre-curved patterns.The band structure analysis suggests that perforation can release part of the in-plane thermal expansion to weaken the softening effect of thermal stress.Introducing precurved components to the perforated structure will stop the decrement of the bandgap frequency in thermal environment,and even make the frequency higher with appropriate structural parameters.The bending stiffness of the heated plate is enhanced by the thermal deflection induced stiffening effect of the pre-curved components.The segmented pre-curved component presents a strong ability to resist the thermal influence on the flexural wave bandgap.A simplified model is established for the local structure of the precurved component.The theoretical calculations explain the thermally induced frequency increment of the bandgap and the discrepancy in the thermal response between the two pre-curved models.The transmittance of flexural wave validates the effectiveness of the proposed design.展开更多
A new multi-detector array named HALIMA(Hybrid Array for LIfetime MeAsurement)has been developed at Lanzhou for nuclear structure studies in fission.The array comprises eight BGO-shielded High-Purity Germanium detecto...A new multi-detector array named HALIMA(Hybrid Array for LIfetime MeAsurement)has been developed at Lanzhou for nuclear structure studies in fission.The array comprises eight BGO-shielded High-Purity Germanium detectors and twenty fast Ce-doped Lanthanum Bromide[LaBr_(3)(Ce)]detectors shielded with CsI(Tl).HALIMA is further complemented by two ancillary detector systems:fission fragment(FF)detectors and β detectors.This configuration enables precise sub-nanosecond lifetime measurements using the fourfold FF/β-Ge-LaBr_(3)(Ce)-LaBr_(3)(Ce)coincidence technique.The performance and specifications of the detectors,associated electronics,and the data acquisition system are presented in detail.The advantage of FF selectivity is emphasized,which significantly enhances sensitivity to specific fission channels.Using this approach,the lifetimes of the nuclear excited states populated in the spontaneous fission of^(252)Cf were measured,showing good agreement with the established literature values.展开更多
Text,as a fundamental carrier of human language and culture,exhibits high structural and semantic complexity.Its systematic analysis is essential for understanding linguistic patterns and cultural transmission.A Dream...Text,as a fundamental carrier of human language and culture,exhibits high structural and semantic complexity.Its systematic analysis is essential for understanding linguistic patterns and cultural transmission.A Dream of Red Mansions and All Men Are Brothers,two masterpieces of Chinese classical literature,have long been central to debates regarding the authorship of their later chapters.Previous studies,often based on word-frequency statistics,function word distributions,entropy measures,and complex network analyses,have provided valuable insights into stylistic differences;however,they remain limited in capturing cross-scale structural features.To address this gap,we apply a multi-scale structural complexity approach based on character-frequency time series to analyze the structural evolution of both novels under various segmentation strategies.Our results reveal significant differences in peak complexity positions,overall complexity levels,and intra-textual variations between the two works,which are closely linked to changes in authorship and stylistic patterns.This study not only provides new quantitative evidence for resolving authorship disputes in classical literature but also demonstrates,from the perspective of structural complexity,the profound depth and unique charm of Chinese literary expression,highlighting the richness of Chinese language and culture.Moreover,it emphasizes the potential of structural complexity analysis as a versatile tool for textual analysis and style attribution.展开更多
A deep-undercooling rapid-solidification technique combining cyclic superheating and molten glass purification was employed to successfully prepare Cu60Ni40 and Cu65Ni35 alloys at various undercooling levels.Furthermo...A deep-undercooling rapid-solidification technique combining cyclic superheating and molten glass purification was employed to successfully prepare Cu60Ni40 and Cu65Ni35 alloys at various undercooling levels.Furthermore,through precise compositional regulation by adjusting the Cu content and introducing Co,the Cu60Ni35Co5 alloy was obtained.The morphological evolution of the solidification front and the variation in solidification rate with undercooling were systematically investigated.By combining metallographic analysis,the BCT model,electron backscatter diffraction(EBSD),and transmission electron microscopy(TEM),the microstructural evolution and grain refinement mechanisms of the undercooled alloys were revealed.This work aims to establish the intrinsic relationship among undercooling,solidification behavior,and microstructure,thereby provides both experimental and theoretical foundations for a deeper understanding of the deep undercooling solidification mechanism and microstructural control.展开更多
Aqueous zinc(Zn)-ion batteries hold great promise as renewable energy storage system for carbon-neutral energy transition.However,Zn anodes suffer from poor Zn plating/stripping reversibility due to Zn dendrite growth...Aqueous zinc(Zn)-ion batteries hold great promise as renewable energy storage system for carbon-neutral energy transition.However,Zn anodes suffer from poor Zn plating/stripping reversibility due to Zn dendrite growth and side reactions.Existing Zn interfacial modification strategies based on single-component or homogeneous structure are insufficient to address these issues comprehensively.Herein,we rationally designed an organic-inorganic hybrid interfacial layer with rigid-to-soft graded structure for dendrite-free and stable Zn anodes.A liquid plasma-assisted oxidation technology is developed to rapidly construct a porous ZnO inner framework in situ.This ZnO layer offers high interfacial energy,mechanical robustness,and an open structure that facilitates ion transport while firmly anchoring a subsequently coated soft polymer layer.The resulting architecture presents a structurally graded and functionally complementary interface,enabling effective dendrite suppression,continuous Zn ion transport,and enhanced corrosion resistance.As a result,a long cycling stability of more than 6000 h can be achieved at 1 mA cm^(-2)for 1 mAh cm^(-2)in symmetric cells.When used as anodes for zinc-iodine full battery,the hybrid interlayer can effectively prevent the Zn anodes from the corrosion by polyiodine,enabling stable cycling and negligible capacity decay(~0.02‰per cycle)for over 10,000 cycles at 2.0 A g^(-1).This work demonstrates a promising interfacial design strategy and introduces a novel liquid plasma-assisted oxidation route for fabricating high-performance Zn anodes towards next-generation aqueous batteries.展开更多
Recent advances in geoscience have underscored the critical role of abiogenic processes in petroleum formation,especially the formation and polymerization of methane.However,whether a direct carbon-H_(2) reaction can ...Recent advances in geoscience have underscored the critical role of abiogenic processes in petroleum formation,especially the formation and polymerization of methane.However,whether a direct carbon-H_(2) reaction can produce C_(2+)hydrocarbons(e.g.,ethane and propane)beyond methane remains an open question.Here,we demonstrate the direct synthesis of ethane and propane via reactions between amorphous carbon and H_(2) under upper mantle conditions(2-10 GPa and 800-1200℃).A systematic investigation reveals that increasing structural disorder in carbon precursors,from graphite to glassy carbon-Ⅱ and carbon black,enhances the production of C_(2)-C_(3) hydrocarbons.Through integrated X-ray diffraction and reverse Monte Carlo simulations,we establish that the continuous random atomic network structures in amorphous carbon enable one-step synthesis of heavy hydrocarbons with H_(2).These models establish a direct link between atomic-scale carbon structures and the one-step synthesis of C_(2+) hydrocarbons under H_(2)-rich,high-pressure,and high-temperature conditions—potentially revealing an efficient mechanism for the abiotic production of C_(2+) hydrocarbons in the upper mantle.展开更多
Superconducting elect rides have attracted growing attention for their potential to achieve high superconducting transition temperatures(T_(C))under pressure.However,many known elect rides are chemically reactive and ...Superconducting elect rides have attracted growing attention for their potential to achieve high superconducting transition temperatures(T_(C))under pressure.However,many known elect rides are chemically reactive and unstable,making high-quality single-crystal growth,characterization,and measurements difficult,and most do not exhibit superconductivity at ambient pressure.In contrast,La_(3) In stands out for its ambient-pressure superconductivity(T_(C)∼9.4 K)and the availability of high-quality single crystals.Here,we investigate its low-energy electronic structure using angle-resolved photoemission spectroscopy and first-principles calculations.The bands near the Fermi energy(E_(F))are mainly derived from La 5d and In 5p orbitals.A saddle point is directly observed at the Brillouin zone(BZ)boundary,while a three-dimensional Van Hove singularity crosses E_(F) at the BZ corner.First-principles calculations further reveal topological Dirac surface states within the bulk energy gap above E_(F).The coexistence of a high density of states and in-gap topological surface states near𝐸F suggests that La3In offers a promising platform for tuning superconductivity and exploring possible topological superconducting phases through doping or external pressure.展开更多
The intracontinental subduction of a>200-km-long section of the Tajik-Tarim lithosphere beneath the Pamir Mountains is proposed to explain nearly 30 km of shortening in the Tajik fold-thrust belt and the Pamir upli...The intracontinental subduction of a>200-km-long section of the Tajik-Tarim lithosphere beneath the Pamir Mountains is proposed to explain nearly 30 km of shortening in the Tajik fold-thrust belt and the Pamir uplift.Seismic imaging revealed that the upper slab was scraped and that the lower slab had subducted to a depth of>150 km.These features constitute the tectonic complexity of the Pamirs,as well as the thermal subduction mechanism involved,which remains poorly understood.Hence,in this study,high-resolution three-dimensional(3D)kinematic modeling is applied to investigate the thermal structure and geometry of the subducting slab beneath the Pamirs.The modeled slab configuration reveals distinct along-strike variations,with a steeply dipping slab beneath the southern Pamirs,a more gently inclined slab beneath the northern Pamirs,and apparent upper slab termination at shallow depths beneath the Pamirs.The thermal field reveals a cold slab core after delamination,with temperatures ranging from 400℃to 800℃,enveloped by a hotter mantle reaching~1400℃.The occurrence of intermediate-depth earthquakes aligns primarily with colder slab regions,particularly near the slab tear-off below the southwestern Pamirs,indicating a strong correlation between slab temperature and seismicity.In contrast,the northern Pamirs exhibit reduced seismicity at depth,which is likely associated with thermal weakening and delamination.The central Pamirs show a significant thermal anomaly caused by a concave slab,where the coldest crust does not descend deeply,further suggesting crustal detachment or mechanical failure.The lateral asymmetry in slab temperature possibly explains the mechanism of lateral tearing and differential slab-mantle coupling.展开更多
Motivated by the recent discovery of superconductivity in the kagome metal CsCr_(3)Sb_(5) under pressure,we theoretically investigate the superconducting pairing symmetry and the impact of spin–orbit coupling(SOC)in ...Motivated by the recent discovery of superconductivity in the kagome metal CsCr_(3)Sb_(5) under pressure,we theoretically investigate the superconducting pairing symmetry and the impact of spin–orbit coupling(SOC)in this system.By employing an effective four-orbital tight-binding model and solving the linearized gap equation within the random phase approximation,we find that the large inter-orbital spin fluctuations enhanced by Hund’s coupling promote a superconducting gap function with E_(2g)symmetry.The inclusion of SOC further stabilizes this gap symmetry.Our analysis also reveals that the d_(x^(2)-y^(2))orbital plays the dominant role in forming the superconducting pairs.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 NSFC(No.12101482)the Natural Science Foundation of Shaanxi Province,China(No.2018JQ1052)。
文摘In this paper,we consider the fourth-order parabolic equation with p(x)Laplacian and variable exponent source ut+∆^(2)u−div(|■u|^(p(x)−2■u))=|u|^(q(x))−1u.By applying potential well method,we obtain global existence,asymptotic behavior and blow-up of solutions with initial energy J(u_(0))≤d.Moreover,we estimate the upper bound of the blow-up time for J(u_(0))≤0.
基金Supported by the National Natural Science Foundation of China(22378181).
文摘The development of materials with excellent microwave absorption(MWA)and electromagnetic interference(EMI)shielding performances has currently received attention.Herein,mesophase pitch-based carbon foam(MPCF)with 3D interconnected pore structure was prepared through the high pressure pyrolysis of mesophase coal tar pitch.It is found that the 3D interconnected cellular pores of MPCF facilitate multiple reflections of electromagnetic waves,which results in the minimum reflection loss(RLmin)value of MPCF reaches-37.84 dB with the effective absorption bandwidth(EAB)of 5.44 GHz at a thickness of 2.70 mm,and the total average electromagnetic shielding effectiveness(SE_(T))under 3.00 mm thickness achieves 26.52 dB in X-band.Subsequently,MPCF is activated by KOH to obtain activated carbon foam(A-MPCF).The average SE_(T)of A-MPCF achieves 103.00 dB for abundant nanopores on the pore cell walls,which leads to a transition from the multiple reflections of electromagnetic waves on the walls to diffuse reflection.Unfortunately,the reflection coefficient(R)of A-MPCF increases from 0.78 to 0.90.To reduce the R value,Fe_(3)O_(4)/A-MPCF was fabricated via the in situ growth of nano Fe_(3)O_(4)on A-MPCF.Consequently,the R value of Fe_(3)O_(4)/A-MPCF was reduced from 0.90 to 0.74,whereas the MWA performance was only slightly decreased.This work proposes a simple strategy for simultaneously adjusting MWA and EMI shielding performances of materials.
基金Funded by the Natural Science Foundation of Fujian Province (No. 2019J01716)the Fujian Provincial Department of Science and Technology (No.2019L3008)。
文摘To evaluate their performance,we constructed organic solar cells using PTB7/Y6 and PTB7-b-PNDI active layers,which were deposited on PET substrates coated with PEDOT:PSS.The ternary solar cells demonstrated an excellent power conversion efficiency after being stretched by 38%.The stretchable organic solar cells were spin-coated on the flexible substrate.The electrodes were formed via liquid metal dropcoating.Solar cell devices based on PET/PH1000/PEDOT:PSS and PTB7:Y6:5% BCP active layer materials show better stretchability than the normal solar cells.The PTB7:Y6:5% BCP-based stretchable organic solar cell achieves a high PCE of 12.3%,and a PCE of 7.8% after stretching.Incorporating block copolymer additives improves the mechanical properties of organic solar cells,thereby enabling superior stretchability.
基金National Science Basic Research Plan in Shaanxi Province of China(Grant No.2025JCYBMS-004).
文摘According to the characteristics of mpox transmission,we establish a class of S1S2EIQR mpox infectious disease models with individual consciousness influence,and obtain the basic reproduction number of the model by using the next generation matrix method.The existence of the endemic equilibrium is demonstrated,and the global asymptotic stability of the disease-free equilibrium is obtained when R0≤1.When R0>1,the disease-free equilibrium is unstable and the endemic equilibrium is globally asymptotically stable.The data of mpox cases from Beijing are collected to simulating the epidemic trends of mpox in the next few months.The results show that increasing the isolation ratio of infected patients,increasing the cure rate of infected patients,and increasing the rate of unconscious to conscious transfer could reduce the cumulative number of mpox infections.
基金funding from FCT(Fundagao para a Ciencia e Tecnologia,I.P.)under the projects LA/P/0037/2020,UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures,Nanomodelling and Nanofabrication-i3Nby the projects FlexSolar(PTDC/CTM-REF/1008/2020),and SpaceFlex(2022.01610.PTDC,DOI:10.54499/2022.01610.PTDC)+1 种基金supported by the project M-ECO2-Industrial Cluster for advanced biofuel production,Ref.C644930471-00000041,R2U Technologies and Befunding from the European Union via the project X-STREAM(Horizon EU,ERC CoG,No 101124803)the support of a fellowship from the"la Caixa"Foundation(ID 100010434)。
文摘Low-dimensional(LD)halide perovskites have attracted considerable attention due to their distinctive structures and exceptional optoelectronic properties,including high absorption coefficients,extended charge carrier diffusion lengths,suppressed non-radiative recombination rates,and intense photoluminescence.A key advantage of LD perovskites is the tunability of their optical and electronic properties through the precise optimization of their structural arrangements and dimensionality.This review systematically examines recent progress in the synthesis and optoelectronic characterizations of LD perovskites,focusing on their structural,optical,and photophysical properties that underpin their versatility in diverse applications.The review further summarizes advancements in LD perovskite-based devices,including resistive memory,artificial synapses,photodetectors,light-emitting diodes,and solar cells.Finally,the challenges associated with stability,scalability,and integration,as well as future prospects,are discussed,emphasizing the potential of LD perovskites to drive breakthroughs in device efficiency and industrial applicability.
文摘In this study,with the aim of achieving a high signal-to-noise ratio(SNR)in an electron-bombarded complementary metal-oxide-semiconductor(EBCMOS)imaging chip,we analyzed the sources of noise using principles from low-light-level imaging and semiconductor theory,and established a physical computational model that relates the electron-multiplication layer to the noise characteristics of an EBCMOS chip in a uniformly doped structure with a P-type substrate.We conducted theoretical calculations to analyze the effects on noise characteristics of the passivation layer material and thickness,P-substrate doping concentration,P-substrate thickness,incident electron energy,and substrate temperature.By comparing the characteristics of pixel noise,dark current,multiplication electron numbers,and SNR under various structures,we simulated optimized structural parameters of the device.Our simulation results showed that the noise characteristics of the device could be optimized using an Al_(2)O_(3)passivation thickness of 15 nm and substrate temperature of 260 K,and by decreasing the doping concentration and thickness of the P-type substrate and increasing the incident electron energy.The optimized SNR were 252 e/e.And the substantial impact of dark current noise,primarily governed by interfacial defects,on the overall noise characteristics of the device.This research offers theoretical support to develop EBCMOS imaging chips with high gain and SNR.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFF0711402)the Specialized Research Fund for State Key Laboratories。
文摘Using a recognition model of atmospheric gravity waves(AGWs),we identified 519 AGW events from the OH airglow images observed at the Dandong and Lhasa stations from 2015 to 2017.The 317 AGW events detected at the Dandong station have wavelengths ranging from 30 to 60 km,periods from 14 to 20 min,horizontal speeds from 30 to 60 m/s,and relative intensities from 0.4%to 0.6%,respectively.The parameters of 202 events recorded at the Lhasa station mainly vary within 15-35 km in horizontal wavelength,4-6 min in period,40-100 m/s in horizontal velocity,and 0.1%-0.3%in relative intensity.The occurrence rate peaks in winter and summer at Dandong and the peak in summer are absent at Lhasa because of the lack of convective weather.The seasonal propagation directions of the waves are influenced by both the wind field-filtering effect and the distribution of wave sources.In spring,because of the southeastward background wind field,fewer southeastward events are observed at the Dandong station.The situation at the Lhasa station is similar.In summer,both the Lhasa and Dandong stations are dominated by northeastward AGWs,which can be attributed to the southwestward wind.In autumn,ray-tracing results show that the events at Dandong mainly originate from wind shear,whereas the events at the Lhasa station are triggered by convective weather.The location of the wave sources determines the trend of the propagation directions at the Dandong and Lhasa stations in autumn.In winter,because of the eastward wind,more events are propagating to the southwest at the Dandong station.
基金funded by Shenzhen Science and Technology Program,grant number No.ZDSYS20230626091400001No.KCXST20221021111609024No.KCXFZ20240903093459001.
文摘This study addresses the energy-intensive challenge of small-scale biogas upgrading by optimizing a chemical absorption process employing methyl diethanolamine(MDEA).Focusing on a typical distributed application of 300 Nm^(3)/d,we developed an integrated simulation-optimization framework using Aspen HYSYS 14.0 to systematically evaluate the effects of critical operating parameters—absorption pressure,MDEA concentration,flow rate,temperature,number of trays,and reboiler duty—on methane purity and energy consumption.The key finding is the identification of an optimal parameter set:absorption pressure of 1200 kPa,MDEA concentration of 20mol%,lean flow rate of 2.5 kmol/h,temperature of 298.15 K,20 absorber trays,10 regenerator trays,and a reboiler duty of 4 kW,which enabled the product gas to achieve a high CH4 concentration of 97mol%,compliant with pipeline standards.A detailed energy consumption analysis revealed that the reboiler is the most energy-intensive unit,accounting for 75.40%of the total 5.29 kW energy consumption,followed by the gas compressor(23.38%).The specific energy consumption for CH4 recovery and the Energy Consumption Index(ECI)were quantified at 0.8852 kWh/kg CH_(4)and 6.82,respectively.This work provides a validated optimization strategy and critical energy breakdown,offering practical guidance for enhancing the technical and economic viability of small-scale,centralized biogas purification systems.
基金Project supported by the National Natural Science Foundation of China(Nos.12102321 and 52192633)the Natural Science Basic Research Plan in Shaanxi Province of China(No.2025JCYBMS-050)。
文摘A design idea for single-component metamaterial plates is proposed to achieve the thermal stability of flexural wave bandgap by the perforated and pre-curved patterns.The band structure analysis suggests that perforation can release part of the in-plane thermal expansion to weaken the softening effect of thermal stress.Introducing precurved components to the perforated structure will stop the decrement of the bandgap frequency in thermal environment,and even make the frequency higher with appropriate structural parameters.The bending stiffness of the heated plate is enhanced by the thermal deflection induced stiffening effect of the pre-curved components.The segmented pre-curved component presents a strong ability to resist the thermal influence on the flexural wave bandgap.A simplified model is established for the local structure of the precurved component.The theoretical calculations explain the thermally induced frequency increment of the bandgap and the discrepancy in the thermal response between the two pre-curved models.The transmittance of flexural wave validates the effectiveness of the proposed design.
基金supported by the National Natural Science Foundation of China(Nos.12275321,12121005,12475129,and 12335009)the Natural Science Foundation of Guangdong Province,China(No.2025A1515012112)+6 种基金the International Atomic Energy Agency Coordinated Research Project F41034(No.28649)the computational resources from Sun Yat-sen University the National Supercomputer Center in Guangzhouthe Open Project of Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology(No.NLK2023-08)the Central Government Guidance Funds for Local Scientific and Technological Development,China(No.Guike ZY22096024)the Guangdong Major Project of Basic and Applied Basic Research(No.2021B0301030006)Young Scientists Fund of the National Natural Science Foundation of China(No.12405144)the National Key Research and Development Program(MOST 2022YFA1602304).
文摘A new multi-detector array named HALIMA(Hybrid Array for LIfetime MeAsurement)has been developed at Lanzhou for nuclear structure studies in fission.The array comprises eight BGO-shielded High-Purity Germanium detectors and twenty fast Ce-doped Lanthanum Bromide[LaBr_(3)(Ce)]detectors shielded with CsI(Tl).HALIMA is further complemented by two ancillary detector systems:fission fragment(FF)detectors and β detectors.This configuration enables precise sub-nanosecond lifetime measurements using the fourfold FF/β-Ge-LaBr_(3)(Ce)-LaBr_(3)(Ce)coincidence technique.The performance and specifications of the detectors,associated electronics,and the data acquisition system are presented in detail.The advantage of FF selectivity is emphasized,which significantly enhances sensitivity to specific fission channels.Using this approach,the lifetimes of the nuclear excited states populated in the spontaneous fission of^(252)Cf were measured,showing good agreement with the established literature values.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12275179,11875042,and12150410309)the Natural Science Foundation of Shanghai(Grant No.21ZR1443900)。
文摘Text,as a fundamental carrier of human language and culture,exhibits high structural and semantic complexity.Its systematic analysis is essential for understanding linguistic patterns and cultural transmission.A Dream of Red Mansions and All Men Are Brothers,two masterpieces of Chinese classical literature,have long been central to debates regarding the authorship of their later chapters.Previous studies,often based on word-frequency statistics,function word distributions,entropy measures,and complex network analyses,have provided valuable insights into stylistic differences;however,they remain limited in capturing cross-scale structural features.To address this gap,we apply a multi-scale structural complexity approach based on character-frequency time series to analyze the structural evolution of both novels under various segmentation strategies.Our results reveal significant differences in peak complexity positions,overall complexity levels,and intra-textual variations between the two works,which are closely linked to changes in authorship and stylistic patterns.This study not only provides new quantitative evidence for resolving authorship disputes in classical literature but also demonstrates,from the perspective of structural complexity,the profound depth and unique charm of Chinese literary expression,highlighting the richness of Chinese language and culture.Moreover,it emphasizes the potential of structural complexity analysis as a versatile tool for textual analysis and style attribution.
基金Funded by the Central Government-Guided Local Development Fund Project(No.YDZJSX2025D042)the Key R&D Program of Shanxi Province(No.202202150401018)+1 种基金the Basic Research Program of Shanxi Province(No.202503021211112)the State Key Laboratory of CAD/CG of Zhejiang University(No.A2325)。
文摘A deep-undercooling rapid-solidification technique combining cyclic superheating and molten glass purification was employed to successfully prepare Cu60Ni40 and Cu65Ni35 alloys at various undercooling levels.Furthermore,through precise compositional regulation by adjusting the Cu content and introducing Co,the Cu60Ni35Co5 alloy was obtained.The morphological evolution of the solidification front and the variation in solidification rate with undercooling were systematically investigated.By combining metallographic analysis,the BCT model,electron backscatter diffraction(EBSD),and transmission electron microscopy(TEM),the microstructural evolution and grain refinement mechanisms of the undercooled alloys were revealed.This work aims to establish the intrinsic relationship among undercooling,solidification behavior,and microstructure,thereby provides both experimental and theoretical foundations for a deeper understanding of the deep undercooling solidification mechanism and microstructural control.
基金support from the Australian Research Council Discovery Program(DP220103416,DP240102177)Australian Research Council Future Fellowships(FT200100730,FT210100804).
文摘Aqueous zinc(Zn)-ion batteries hold great promise as renewable energy storage system for carbon-neutral energy transition.However,Zn anodes suffer from poor Zn plating/stripping reversibility due to Zn dendrite growth and side reactions.Existing Zn interfacial modification strategies based on single-component or homogeneous structure are insufficient to address these issues comprehensively.Herein,we rationally designed an organic-inorganic hybrid interfacial layer with rigid-to-soft graded structure for dendrite-free and stable Zn anodes.A liquid plasma-assisted oxidation technology is developed to rapidly construct a porous ZnO inner framework in situ.This ZnO layer offers high interfacial energy,mechanical robustness,and an open structure that facilitates ion transport while firmly anchoring a subsequently coated soft polymer layer.The resulting architecture presents a structurally graded and functionally complementary interface,enabling effective dendrite suppression,continuous Zn ion transport,and enhanced corrosion resistance.As a result,a long cycling stability of more than 6000 h can be achieved at 1 mA cm^(-2)for 1 mAh cm^(-2)in symmetric cells.When used as anodes for zinc-iodine full battery,the hybrid interlayer can effectively prevent the Zn anodes from the corrosion by polyiodine,enabling stable cycling and negligible capacity decay(~0.02‰per cycle)for over 10,000 cycles at 2.0 A g^(-1).This work demonstrates a promising interfacial design strategy and introduces a novel liquid plasma-assisted oxidation route for fabricating high-performance Zn anodes towards next-generation aqueous batteries.
基金mainly supported by the Natural Science Foundation of China (Grant Nos. 52288102, 52090020, and 52372261)the Natural Science Foundation of Hebei Province (Grant No. E202403045)+1 种基金the S&T Program of Hebei (Grant No. 225A1102D)the Ministry of Education Chang Jiang Scholar Professor Program (Grant No. T2022241)
文摘Recent advances in geoscience have underscored the critical role of abiogenic processes in petroleum formation,especially the formation and polymerization of methane.However,whether a direct carbon-H_(2) reaction can produce C_(2+)hydrocarbons(e.g.,ethane and propane)beyond methane remains an open question.Here,we demonstrate the direct synthesis of ethane and propane via reactions between amorphous carbon and H_(2) under upper mantle conditions(2-10 GPa and 800-1200℃).A systematic investigation reveals that increasing structural disorder in carbon precursors,from graphite to glassy carbon-Ⅱ and carbon black,enhances the production of C_(2)-C_(3) hydrocarbons.Through integrated X-ray diffraction and reverse Monte Carlo simulations,we establish that the continuous random atomic network structures in amorphous carbon enable one-step synthesis of heavy hydrocarbons with H_(2).These models establish a direct link between atomic-scale carbon structures and the one-step synthesis of C_(2+) hydrocarbons under H_(2)-rich,high-pressure,and high-temperature conditions—potentially revealing an efficient mechanism for the abiotic production of C_(2+) hydrocarbons in the upper mantle.
基金supported by the National Natural Science Foundation of China(Grant Nos.12222413,12174443,12274459,and 12404266)the National Key R&D Program of China(Grant Nos.2023YFA1406500,2022YFA1403800,and 2022YFA1403103)+3 种基金the Natural Science Foundation of Shanghai (Grant No.23ZR1482200)the Natural Science Foundation of Ningbo (Grant No.2024J019)the Science Research Project of Hebei Education Department (Grant No.BJ2025060)the funding of Ningbo Yongjiang Talent Program。
文摘Superconducting elect rides have attracted growing attention for their potential to achieve high superconducting transition temperatures(T_(C))under pressure.However,many known elect rides are chemically reactive and unstable,making high-quality single-crystal growth,characterization,and measurements difficult,and most do not exhibit superconductivity at ambient pressure.In contrast,La_(3) In stands out for its ambient-pressure superconductivity(T_(C)∼9.4 K)and the availability of high-quality single crystals.Here,we investigate its low-energy electronic structure using angle-resolved photoemission spectroscopy and first-principles calculations.The bands near the Fermi energy(E_(F))are mainly derived from La 5d and In 5p orbitals.A saddle point is directly observed at the Brillouin zone(BZ)boundary,while a three-dimensional Van Hove singularity crosses E_(F) at the BZ corner.First-principles calculations further reveal topological Dirac surface states within the bulk energy gap above E_(F).The coexistence of a high density of states and in-gap topological surface states near𝐸F suggests that La3In offers a promising platform for tuning superconductivity and exploring possible topological superconducting phases through doping or external pressure.
基金the Chinese Academy of Sciences Pioneer Hundred Talents Program and the Second Tibetan Plateau Scientific Expedition and Research Program(Grant No.2019QZKK0708)supported by a MEXT(Ministry of Education,Culture,Sports,Science and Technology)KAKENHI(Grants-in-Aid for Scientific Research)grant(Grant No.21H05203)Kobe University Strategic International Collaborative Research Grant(Type B Fostering Joint Research).
文摘The intracontinental subduction of a>200-km-long section of the Tajik-Tarim lithosphere beneath the Pamir Mountains is proposed to explain nearly 30 km of shortening in the Tajik fold-thrust belt and the Pamir uplift.Seismic imaging revealed that the upper slab was scraped and that the lower slab had subducted to a depth of>150 km.These features constitute the tectonic complexity of the Pamirs,as well as the thermal subduction mechanism involved,which remains poorly understood.Hence,in this study,high-resolution three-dimensional(3D)kinematic modeling is applied to investigate the thermal structure and geometry of the subducting slab beneath the Pamirs.The modeled slab configuration reveals distinct along-strike variations,with a steeply dipping slab beneath the southern Pamirs,a more gently inclined slab beneath the northern Pamirs,and apparent upper slab termination at shallow depths beneath the Pamirs.The thermal field reveals a cold slab core after delamination,with temperatures ranging from 400℃to 800℃,enveloped by a hotter mantle reaching~1400℃.The occurrence of intermediate-depth earthquakes aligns primarily with colder slab regions,particularly near the slab tear-off below the southwestern Pamirs,indicating a strong correlation between slab temperature and seismicity.In contrast,the northern Pamirs exhibit reduced seismicity at depth,which is likely associated with thermal weakening and delamination.The central Pamirs show a significant thermal anomaly caused by a concave slab,where the coldest crust does not descend deeply,further suggesting crustal detachment or mechanical failure.The lateral asymmetry in slab temperature possibly explains the mechanism of lateral tearing and differential slab-mantle coupling.
基金supported by the National Key Research and Development of China(Grant Nos.2024YFA1408104 and 2021YFA1400400)the National Natural Science Foundation of China(Grant Nos.12374137,12434005,12074175,92165205,12004191,and 12550405)the Natural Science Foundation of Jiangsu Province(Grant No.BK20233001)。
文摘Motivated by the recent discovery of superconductivity in the kagome metal CsCr_(3)Sb_(5) under pressure,we theoretically investigate the superconducting pairing symmetry and the impact of spin–orbit coupling(SOC)in this system.By employing an effective four-orbital tight-binding model and solving the linearized gap equation within the random phase approximation,we find that the large inter-orbital spin fluctuations enhanced by Hund’s coupling promote a superconducting gap function with E_(2g)symmetry.The inclusion of SOC further stabilizes this gap symmetry.Our analysis also reveals that the d_(x^(2)-y^(2))orbital plays the dominant role in forming the superconducting pairs.
