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Numerical investigation of the concentric annulus flow around a cylindrical body with contrasted effecting factors 被引量:8
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作者 张雪兰 孙西欢 +3 位作者 李永业 郗夏楠 郭飞 郑利剑 《Journal of Hydrodynamics》 SCIE EI CSCD 2015年第2期273-285,共13页
This paper studies the wall-bounded flow around a cylindrical at a high Reynolds numbers body in a determined computational domain, with simulations of the 3-D, turbulent concentric annulus flow in a straight pipe. Nu... This paper studies the wall-bounded flow around a cylindrical at a high Reynolds numbers body in a determined computational domain, with simulations of the 3-D, turbulent concentric annulus flow in a straight pipe. Numerical results show that a reversing zone, appearing as a tongue zone with nested velocities higher than the surrounding area, exists behind the cylindrical body. The annulus space is a region of high velocity and low pressure. The zero velocity, of combined the X- velocity and the Y- velocity, exists in the cross sections and no vortex shedding is formed behind the attaching cylinders. Among all investigated effecting factors, the diameters of the attaching and the main cylinders affect the wake feature behind the cylindrical body while the main cylinder length does not affect the distribution tendency of the flow field. The diameters of the main cylinder and the pipe affect the pressure values and the distribution tendencies on the main cylinder surface. Obviously, the increase of the pipe diameter reduces the drag coefficient of the cylindrical body and the increase of the diameter of the main cylinder increases the drag coefficient greatly. The numerical investigation of the concentric annulus flow provides foundations for further improvements of the intricate flow studies. 展开更多
关键词 numerical investigation concentric annulus turbulent flow contrasted effecting factors hydraulic characteristics
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Material removal mechanism of SiC_(f)/SiC composites during ultrasonic-assisted scratching with vertical vibration 被引量:1
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作者 Zhigang DONG Guoqing YUAN +3 位作者 Yichuan RAN Haiqi SUN Jiansong SUN Yan BAO 《Chinese Journal of Aeronautics》 2026年第1期584-600,共17页
Ultrasonic-Assisted Grinding(UAG)is a novel manufacturing technology that shows promising promise for use in processing Ceramic Matrix Composites(CMCs).Nevertheless,analyzing the material removal process of CMCs with ... Ultrasonic-Assisted Grinding(UAG)is a novel manufacturing technology that shows promising promise for use in processing Ceramic Matrix Composites(CMCs).Nevertheless,analyzing the material removal process of CMCs with multidirectional structure during UAG is challenging,impeding the progress and improvement of the UAG process.This work examined the impact of ultrasonic vibration on the dynamic mechanical characteristics during processing.Additionally,we experimentally elucidated the material removal mechanism of CMCs during the scratching process under the influence of vertical vibration.The results indicate that the introduction of ultrasonic vibration causes a strain rate effect,resulting in a modification of the material removal mechanism,subsequently impacting the processing quality.Ultrasonic vibration increases the dynamic strength and brittleness of the fibers in CMCs,leading to more cracks at fracture,which changes from the original bending fracture to shear fracture.In addition,ultrasonic vibration can effectively inhibit the impact of scratching depth and anisotropy on the removal mechanism of CMCs,resulting in a more uniform surface of CMCs after processing. 展开更多
关键词 Ceramic-matrix composites Ultrasonic assisted scratching(UAS) Strain rate effect Dynamic mechanical property Material removal mechanism
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Amino‑modified F‑containing silica slag for the construction of multi‑functional interlayer and the inhibitory effect on the polysulfide shuttle effect in lithium‑sulfur batteries
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作者 LIAO Yuxin SHEN Xianheng +4 位作者 CHEN Li TIAN Yujia LUO Zhihong CHEN Xiaoli SHAO Jiaojing 《无机化学学报》 北大核心 2026年第2期375-386,共12页
Herein,3‑aminopropyltriethoxysilane(APTES)was used to modify F‑containing silica slag(SS)by simple grafting and served as a multifunctional barrier layer.The amino group(—NH2)in the amino‑modified SS(NH2‑SS)forms lig... Herein,3‑aminopropyltriethoxysilane(APTES)was used to modify F‑containing silica slag(SS)by simple grafting and served as a multifunctional barrier layer.The amino group(—NH2)in the amino‑modified SS(NH2‑SS)forms ligand bonds or hydrogen bonds with sulfur ions in lithium polysulfides(LiPSs),thus inhibiting the shuttle effect.Electrochemical analyses demonstrated that lithium‑sulfur(Li‑S)batteries employing the NH2‑SS interlayer exhibited discharge specific capacities of 1048 and 789 mAh·g^(-1) at 0.2C and 2C,respectively,and even at 4C,the initial discharge specific capacity remained at 590 mAh·g^(-1),outperforming the Li‑S battery with unmodified SS as the interlayer. 展开更多
关键词 SILICA INTERLAYER shuttle effect lithium‑sulfur batteries
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Evaluation of Low-Damping Properties Induced by Plastic Deformation and Heat Treatment in Co-Ni-Cr-Mo-Based Alloy
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作者 Wang Hao Tong Haotian +2 位作者 Tadashi Fujieda Takemi Chiba Akihiko Chiba 《稀有金属材料与工程》 北大核心 2026年第3期573-580,共8页
The strength and damping properties of Co-Ni-Cr-Mo-based alloys with 0.5wt%Nb addition after various plastic deformation and heat treatment processes were investigated.Through Vickers hardness tests,free resonance You... The strength and damping properties of Co-Ni-Cr-Mo-based alloys with 0.5wt%Nb addition after various plastic deformation and heat treatment processes were investigated.Through Vickers hardness tests,free resonance Young's modulus measurements,and microstructure analysis,the effects of dislocation density,vacancy formation,and recrystallization on the alloy performance were clarified.Results indicate that increasing the rolling reduction enhances damping property due to higher dislocation density,whereas aging below the recrystallization temperature reduces damping property via dislocation pinning by the Suzuki effect.Recrystallization heat treatment restores the original structure and damping level.This alloy possesses tensile strength of approximately 1500 MPa and logarithmic decrement valueδ^(-1) in the range of 2×10^(-4)–3×10^(-4),demonstrating superior mechanical properties compared with the Ti-based alloys,which makes it an excellent candidate material for ultrasonic tools and medical applications. 展开更多
关键词 Co-Ni-Cr-Mo-based alloy low-damping properties Suzuki effect plastic deformation
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In-Flight Heating Process of Cerium Oxide Powders in Radio Frequency Thermal Plasma Considering Thermal Resistance Effect
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作者 Su Yi Liu Ruizhe +3 位作者 Ahmad Hilal Zhao Peng Jin Xingyue Zhu Hailong 《稀有金属材料与工程》 北大核心 2026年第3期581-594,共14页
The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF... The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF)argon plasma,and the temperatures were measured using a DPV-2000 monitor.A model combining the electromagnetism,thermal flow,and heat transfer characteristics of powder during in-flight heating in argon plasma was proposed.The melting processes of CeO_(2)powders of different diameters,with and without thermal resistance effect,were investigated.Results show that the heating process of CeO_(2)powder particles consists of three main stages,one of which is relevant to a dimensionless parameter known as the Biot number.When the Biot value≥0.1,thermal resistance increases significantly,especially for the larger powders.The predicted temperature of the particles at the outlet(1800–2880 K)is in good agreement with the experimental result. 展开更多
关键词 RF thermal plasma thermal resistance effect heating process Biot number
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A carbon sponge supporting a MoS_(2)-Mo_(2)C heterostructure as the Li_(2)S host for high-performance lithium sulfur batteries
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作者 Ji Yuanxiao Zhang Weiye +7 位作者 Xue Jiarui Zhang Jiyuan Ge Yunping Zhu Nan Jiang Ruibin Lei Zhibin Liu Zonghuai Sun Jie 《新型炭材料(中英文)》 北大核心 2026年第1期109-126,共18页
Despite their high theoretical capacity and energy density,lithiumsulfur(Li–S)batteries still face challenges such as soluble lithium polysulfides(LiPSs)shuttling and sluggish redox kinetics.In this work,we used a no... Despite their high theoretical capacity and energy density,lithiumsulfur(Li–S)batteries still face challenges such as soluble lithium polysulfides(LiPSs)shuttling and sluggish redox kinetics.In this work,we used a novel MoS_(2)-Mo_(2)C heterostructure anchored on a carbon sponge(CS)as a Li_(2)S host to solve these problems.A simple hydrothermal process following carbothermal reduction was used to construct the MoS_(2)-Mo_(2)C heterostructure,enabling control of the phases and integration of MoS_(2) and Mo_(2)C.Structural characterization confirmed the coherent interface of the heterostructure with a precise orientation relationship between the two phases and their uniform distribution.An evaluation of the adsorption and catalytic performance of the material showed that it has an exceptional LiPSs adsorption capacity with faster conversion from Li_(2)S_(4) to Li_(2)S_(2).Density functional theory calculations further confirmed these results.As a result,the cathode had a high initial discharge capacity of 693 mAh g^(−1) at 0.2 C and achieved stable cycling at 2 C for 500 cycles with a low decay rate of 0.107%per cycle.The heterostructure design,coupled with the macroporous CS framework,effectively prevented the shuttling and increased sulfur utilization,offering a promising way to produce practical high-energydensity Li–S batteries. 展开更多
关键词 Lithium-sulfur batteries HETEROSTRUCTURE Carbon sponge Li_(2)S host Shuttle effect
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Silver chloride/chitosan‑based chloramine nanohybrid with excellent antibacterial activity:Design and structure characterization as well as Ag^(+)‑Cl^(-)synergistic antibacterial effect
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作者 ZHANG Xinzhe XU Jiarong +4 位作者 GAO Mochou LIU Yage ZHAO Yanbao CUI Jingzeng ZOU Xueyan 《无机化学学报》 北大核心 2026年第2期428-438,共11页
Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticle... Chitosan(CTS)was grafted onto the surface of amino‑functionalized silver chloride silicon dioxide(AgCl@SiO_(2)‑NH_(2))cores to obtain AgCl@SiO_(2)/CTS hybrid nanoparticles.The as‑obtained AgCl@SiO_(2)/CTS nanoparticles were chlorinated by NaClO solution to get AgCl@SiO_(2)/CTS‑based chloramine nano‑hybrid materials,denoted as AgCl@SiO_(2)/CTS‑Cl.A transmission electron microscope was used to observe the morphology of the as‑prepared samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.At the same time,an X‑ray diffractometer and an infrared spectroscope were utilized to characterize their crystal and chemical structures.Besides,ζpotentials were measured to elucidate the surface modification of AgCl nanoparticles by—NH_(2),the antibacterial mechanism of AgCl@SiO_(2)/CTS‑Cl was investigated by scanning electron microscopy,and Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were used as the to‑be‑tested strains to evaluate the antimicrobial activity of samples AgCl@SiO_(2)/CTS and AgCl@SiO_(2)/CTS‑Cl.Findings demonstrate that sample AgCl@SiO_(2)/CTS exhibits a chain‑like structure ascribed to the interaction between—NH_(2),and each AgCl@SiO_(2)/CTS hybrid nanoparticle contains several AgCl cores.In the meantime,sample AgCl@SiO_(2)/CTS‑Cl exhibits excellent antibacterial activity against E.coli and S.aureus,which is attributed to the synergistic antibacterial effect of Ag^(+)and Cl^(-).Sample AgCl@SiO_(2)/CTS‑Cl with a dosage of 640.00μg·mL^(-1) could completely kill the two kinds of tested bacteria in 12 h of incubation;it retains a high antibacterial efficiency even after 10 cycles of antibacterial tests. 展开更多
关键词 AgCl@SiO_(2)/CTS‑Cl hybrid nanoparticle synergistic effect antibacterial activity
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Theoretical study on the thermally activated delayed fluorescence,and efficiency roll‑off characteristics of a series of blue and blue‑green Ir(Ⅲ)complexes
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作者 QIN Zhengkun BAO Lixin +4 位作者 ZHANG Yunkai CUI Lin WANG Jinyu WANG Yuhao SONG Mingxing 《无机化学学报》 北大核心 2026年第2期365-374,共10页
A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescenc... A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine. 展开更多
关键词 organic light‑emitting diodes Ir(Ⅲ)complex time‑dependent density functional theory thermal activation delayed fluorescence property efficiency roll‑off effect
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Comparing clinical performance of two-rod levonorgestrel implants across brands:A three-year multicenter randomized clinical trial on Sinoplant and Indoplant
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作者 Djaswadi Dasuki Hendy Hendarto +11 位作者 Delfi Lutan Muhammad N.Rahman Muhammad O.Prabudi Indra G.Munthe Jimmy Y.Annas Shinta Prawitasari Muhammad Lutfi Sarrah Ayuandari Endah Rahmawati Arif Tunjungseto Adi Ariffianto Irfan Haris 《Asian pacific Journal of Reproduction》 2026年第1期2-10,共9页
Objective:To compare the effectiveness,safety,acceptability,and confounding factors of the two-rod levonorgestrel implants between the Indoplant and Sinoplant implant brands.Methods:The study was a double-blind,random... Objective:To compare the effectiveness,safety,acceptability,and confounding factors of the two-rod levonorgestrel implants between the Indoplant and Sinoplant implant brands.Methods:The study was a double-blind,randomized controlled trial at three different centers in Indonesia.A total of 531 participants that met inclusion and exclusion criteria were randomized into two groups,with 264 participants in the Sinoplant group and 267 participants in the Indoplant group.At each center,participants were divided into two groups for Sinoplant and Indoplant.The participants were followed up for 36 months.Four parameters were evaluated:implant effectiveness,safety,acceptability,and confounding factors.Results:A total of 531 eligible participants were enrolled in this study.Both Sinoplant and Indoplant showed 100%efficacy in preventing pregnancy,with no significant differences in side effects.24.22%of the Sinoplant group and 22.18%of the Indoplant group reported weight changes.8.60%of the Sinoplant group and 9.73%of the Indoplant group reported menstrual changes,and 1.17%of the both groups experienced intermenstrual bleeding.Implant acceptability was 96.61%,with 3.39%dropout rates.Confounding factors such as age,parity,and contraceptive history did not significantly differ between the two groups.Conclusions:Sinoplant and Indoplant did not differ significantly in contraceptive effectiveness,safety,acceptability,and confounding factors. 展开更多
关键词 CONTRACEPTIVES IMPLANTS LEVONORGESTREL Effectiveness ACCEPTABILITY Side effects
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Broadband ground motion simulation and analysis of a near-fault 3D basin-mountain coupling site based on the hybrid method
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作者 Liu Zhongxian Tang Kang +2 位作者 Li Chengcheng Yuan Xiaoming Zhang Hai 《Earthquake Engineering and Engineering Vibration》 2026年第1期87-110,共24页
This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SE... This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SEM),which is used to simulate low-frequency ground motion(f<1 Hz)by incorporating an innovative efficient discontinuous Galerkin(DG)method for grid division to accurately model basin sedimentary layers at reduced costs.It also introduces a comprehensive hybrid source model for high-frequency random scattering and a nonlinear analysis module for basin sedimentary layers.Deterministic outcomes are combined with modified three-dimensional stochastic finite fault method(3D-EXSIM)simulations of high-frequency ground motion(f>1 Hz).A fourth-order Butterworth filter with zero phase shift is employed for time-domain filtering of low-and high-frequency time series at a crossover frequency of 1 Hz,merging the low and high-frequency ground motions into a broadband time series.Taking an Ms 6.8 Luding earthquake,as an example,this hybrid method was used for a rapid and efficient simulation analysis of broadband ground motion in the region.The accuracy and efficiency of this hybrid method were verified through comparisons with actually observed station data and empirical attenuation curves.Deterministic method simulation results revealed the effects of mountainous topography,basin effects,nonlinear effects within the basin’s sedimentary layers,and a coupling interaction between the basin and the mountains.The findings are consistent with similar studies,showing that near-fault sedimentary basins significantly focus and amplify strong ground motion,and the soil’s nonlinear behavior in the basin influences ground motion to varying extents at different distances from the fault.The mountainous topography impacts the basin’s response to ground motion,leading to barrier effects.This research provides a scientific foundation for seismic zoning,urban planning,and seismic design in nearfault mountain basin regions. 展开更多
关键词 hybrid ground motion simulation method spectral element method three-dimensional stochastic finite fault method near-fault basin-mountain coupling effect basin effect nonlinear effect
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Electronically Conductive Metal−Organic Framework With Photoelectric and Photothermal Effect as a Stable Cathode for High-Temperature Photo-Assisted Zn/Sn-Air Battery
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作者 Jiangchang Chen Chuntao Yang +2 位作者 Yao Dong Ya Han Yingjian 《Carbon Energy》 2026年第1期105-114,共10页
Rechargeable Zn/Sn-air batteries have received considerable attention as promising energy storage devices.However,the electrochemical performance of these batteries is significantly constrained by the sluggish electro... Rechargeable Zn/Sn-air batteries have received considerable attention as promising energy storage devices.However,the electrochemical performance of these batteries is significantly constrained by the sluggish electrocatalytic reaction kinetics at the cathode.The integration of light energy into Zn/Sn-air batteries is a promising strategy for enhancing their performance.However,the photothermal and photoelectric effects generate heat in the battery under prolonged solar irradiation,leading to air cathode instability.This paper presents the first design and synthesis of Ni_(2)-1,5-diamino-4,8-dihydroxyanthraquinone(Ni_(2)DDA),an electronically conductiveπ-d conjugated metal-organic framework(MOF).Ni_(2)DDA exhibits both photoelectric and photothermal effects,with an optical band gap of~1.14 eV.Under illumination,Ni_(2)DDA achieves excellent oxygen evolution reaction performance(with an overpotential of 245 mV vs.reversible hydrogen electrode at 10 mA cm^(−2))and photothermal stability.These properties result from the synergy between the photoelectric and photothermal effects of Ni_(2)DDA.Upon integration into Zn/Sn-air batteries,Ni_(2)DDA ensures excellent cycling stability under light and exhibits remarkable performance in high-temperature environments up to 80℃.This study experimentally confirms the stable operation of photo-assisted Zn/Sn-air batteries under high-temperature conditions for the first time and provides novel insights into the application of electronically conductive MOFs in photoelectrocatalysis and photothermal catalysis. 展开更多
关键词 electronically conductive MOFs high temperatures photo-assisted Zn/Sn-air batteries photoelectric effects photothermal effects
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Impact of Green Finance on Agricultural Green Development in Henan Province
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作者 Lefeng LIN Yi SHEN +1 位作者 Cheng MA Sihai ZHANG 《Asian Agricultural Research》 2026年第1期14-17,24,共5页
Against the backdrop of China s accelerated green development and its pursuit of the"dual carbon"goals,green finance,as a crucial instrument for the rational allocation of resources,plays a significant role ... Against the backdrop of China s accelerated green development and its pursuit of the"dual carbon"goals,green finance,as a crucial instrument for the rational allocation of resources,plays a significant role in promoting agricultural green transformation.Taking Henan Province as a case study,this research employs panel data from 18 prefecture-level cities spanning 2014 to 2023,utilizing dynamic panel models and mediating effect models for empirical analysis.The findings reveal that green finance indirectly fosters agricultural green development by driving agricultural technological progress.This promoting effect is significant,with the mediating effect accounting for 3.67%.Based on these results,policy recommendations are proposed:expanding the coverage of green finance and constructing a diversified product system;comprehensively promoting agricultural technological innovation and mechanization development;and coordinating and integrating green financial resources to facilitate agricultural green transformation tailored to local conditions. 展开更多
关键词 Green FINANCE AGRICULTURAL green DEVELOPMENT Mediating EFFECT
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Kibble–Zurek Meets Tricriticality:Breakdown of Adiabatic-Impulse and New Scaling Forms
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作者 Chengshu Li 《Chinese Physics Letters》 2026年第1期1-2,共2页
The Kibble-Zurek (KZ) effect offers an overarching description of dynamical scaling behavior near a critical point.[1,2] Originally proposed in a classical setup,the KZ effect has been generalized to quantum phase tra... The Kibble-Zurek (KZ) effect offers an overarching description of dynamical scaling behavior near a critical point.[1,2] Originally proposed in a classical setup,the KZ effect has been generalized to quantum phase transitions[3-5] and is actively explored on quantum simulation platforms.[6-9] Exploring how the KZ effect fares across different criticalities has proven to be a rewarding pursuit,significantly enriching our understanding of nonequilibrium quantum dynamics.[3-5,10-23] 展开更多
关键词 quantum phase transitions dynamical scaling behavior kz effect kibble zurek effect tricriticality quantum simulation platforms nonequilibrium quantum dynamics critical point
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Genome editing in horticultural crops:augmenting trait development and stress resilience
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作者 Hamza Sohail Iqra Noor +4 位作者 Hammad Hussain Lili Zhang Xuewen Xu Xuehao Chen Xiaodong Yang 《Horticultural Plant Journal》 2026年第1期1-18,共18页
Horticultural crops are important for global nutrition,health,and economic security but are increasingly challenged by climate change and environmental stresses.The advent of CRISPR/Cas9(Clustered Regularly Interspace... Horticultural crops are important for global nutrition,health,and economic security but are increasingly challenged by climate change and environmental stresses.The advent of CRISPR/Cas9(Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-Associated Protein 9)has revolutionized precision breeding by enabling targeted gene modifications that enhance yield,disease resistance,and stress tolerance.This review summarizes recent advancements in the application of CRISPR/Cas9 across fruit,vegetable,and ornamental crops,highlighting key achievements in enhancing crop quality,shelf life,and resilience.It also explores the potential of base and prime editing technologies,which offer greater precision and reduced risk of unintended mutations.Despite these advancements,the practical use of genome editing in horticulture faces persistent challenges,including inefficient delivery systems,off-target effects,and the limited regeneration capacity of many species.Furthermore,regulatory ambiguity,ethical considerations,and public skepticism continue to shape the global acceptance and commercialization of genome-edited crops.Integrating CRISPR-based tools into mainstream horticultural breeding programs offers a pathway for the development of climate-resilient,high-quality crops and for sustainable agricultural development in the face of global challenges. 展开更多
关键词 Breeding CRISPR MUTAGENESIS Off-target effects TRANSGENE
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Effects of Ecological Ditch and Wetland in Reducing Farmland Drainage Pollutants in Hetao Irrigation District
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作者 Zhen HU Qiong LIAO +4 位作者 Xu LI Wei QIAO Xiang ZENG Yongbing HUANG Wei REN 《Asian Agricultural Research》 2026年第1期25-32,共8页
[Objectives]To explore the control mode of farmland drainage pollutants and investigate the effects of ecological ditch and wetland on reducing farmland drainage pollutants in Hetao Irrigation District.[Methods]Based ... [Objectives]To explore the control mode of farmland drainage pollutants and investigate the effects of ecological ditch and wetland on reducing farmland drainage pollutants in Hetao Irrigation District.[Methods]Based on the demonstration construction project of the ecological ditch-constructed wetland system in the Hetao Irrigation District,an experimental study was conducted from July to September 2023 to investigate the interception and purification effects of ecological ditches,constructed wetlands,and the combined ecological ditch-constructed wetland system on farmland drainage pollutants.Key water quality parameters measured included total nitrogen(TN)concentration and total phosphorus(TP)concentration.[Results]Different treatment modes of ecological ditches and constructed wetlands have a certain removal effect on nitrogen and phosphorus pollutants in water bodies.The ecological ditches treated with Astragalus laxmannii,Melilotus officinalis,Medicago sativa,bio-ball substrate,and bio-sheet substrate showed reduction efficiencies for TN and TP of 21.09% and 23.84%,12.06% and 26.67%,20.08% and 34.15%,23.65% and 20.56%,and 19.92% and 25.83%,respectively.The emergent plant area showed reduction efficiencies of 24.28%for TN and 17.89%for TP,while the submerged plant area achieved a reduction efficiency of 10.21%for both TN and TP.Among the different treatment modes,the ecological ditch with M.sativa performed better in TP removal,whereas the bio-ball substrate treatment mode showed higher effectiveness in TN removal.In addition,the emergent plant area exhibited better TP removal performance,while the submerged plant area was more effective in TN removal.The combined system of ecological ditch and constructed wetland achieved removal rates of 37.55% for TN and 11.47% for TP.It effectively facilitates the step-by-step interception and adsorption purification of pollutants,thereby showing significant removal and purification effects on nitrogen and phosphorus contaminants.This contributes to mitigating agricultural non-point source pollution.[Conclusions]The combined ecological ditch-constructed wetland system serves dual functions of agricultural drainage and pollutant interception and purification.It reduces the pollution load of farmland drainage on receiving water bodies to some extent and mitigates agricultural non-point source pollution.Therefore,it is a relatively suitable technology for managing agricultural non-point source pollution in the Hetao Irrigation District. 展开更多
关键词 Ecological DITCH CONSTRUCTED WETLAND POLLUTANT Purification effect HETAO Irrigation District
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A review of phytonutrients and human anti-aging mechanism
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作者 Yun-Chao Feng Jian-Heng Zheng +8 位作者 Lu Ren Yi-Sha Shen Ya-Xin Dong Sheng Ji Dan Han Ying-Yi Luo Li-Qiang Wang Zong-Hui Cui Ying Qing 《Life Research》 2026年第1期17-34,共18页
Aging is a complex biological process characterized by nine hallmarks,including genomic instability,mitochondrial dysfunction,and chronic inflammation,which collectively drive the progression of age-related chronic no... Aging is a complex biological process characterized by nine hallmarks,including genomic instability,mitochondrial dysfunction,and chronic inflammation,which collectively drive the progression of age-related chronic non-communicable diseases.Phytonutrients,a class of bioactive secondary metabolites abundant in plants,have emerged as a promising research focus for intervening in the aging process due to their multifaceted biological activities.This review systematically elaborates on the molecular mechanisms,key signaling pathways,specifically SIRT1,Nrf2/ARE,and AMPK/mTOR,and the synergistic anti-aging effects of four typical phytonutrient categories:polyphenols(e.g.,resveratrol,quercetin),carotenoids(e.g.,lycopene,astaxanthin),sulfur compounds(e.g.,α-lipoic acid,ergothioneine),and phytoestrogens(e.g.,soybean isoflavones).The evidence indicates that these compounds combat aging through a multidimensional network involving direct antioxidant actions,free radical scavenging,metal chelation,promotion of autophagy,and modulation of inflammatory and epigenetic pathways.Crucially,the review highlights that synergistic interactions between different phytonutrients can significantly enhance their efficacy beyond the effect of any single compound.The aim is to consolidate the anti-aging evidence of phytonutrients and address the current translational challenges,such as bioavailability and a lack of robust human trials,thereby providing a comprehensive theoretical framework for developing effective,diet-centered strategies to promote healthy aging and reduce the global burden of non-communicable diseases. 展开更多
关键词 phytonutrients ANTI-AGING POLYPHENOLS carotenoids synergistic effects
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KTaO_(3)-Based Editable Superconducting Diode
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作者 Yishuai Wang Wenze Pan +1 位作者 Meng Zhang Yanwu Xie 《Chinese Physics Letters》 2026年第1期297-321,共25页
Superconducting diodes,which enable dissipationless supercurrent flow in one direction while blocking it in the reverse direction,are emerging as pivotal components for superconducting electronics.The development of e... Superconducting diodes,which enable dissipationless supercurrent flow in one direction while blocking it in the reverse direction,are emerging as pivotal components for superconducting electronics.The development of editable superconducting diodes could unlock transformative applications,including dynamically reconfigurable quantum circuits that adapt to operational requirements.Here,we report the first observation of the superconducting diode effect(SDE)in LaAlO_(3)/KTaO_(3) heterostructures—a two-dimensional oxide interface superconductor with exceptional tunability.We observe a strong SDE in Hall-bar(or strip-shaped)devices under perpendicular magnetic fields(<15 Oe),with efficiencies above 40%and rectification signals exceeding 10 mV.Through conductive atomic force microscope lithography,we demonstrate reversible nanoscale editing of the SDE’s polarity and efficiency by locally modifying the superconducting channel edges.This approach enables multiple nonvolatile configurations within a single device,realizing an editable superconducting diode.Our work establishes LaAlO_(3)/KTaO_(3) as a platform for vortex-based nonreciprocal transport and provides a pathway toward designer quantum circuits with on-demand functionalities. 展开更多
关键词 superconducting diodeswhich dissipationless supercurrent flow superconducting diode effect superconducting diode effect sde superconducting electronicsthe editable superconducting diodes dynamically reconfigurable quantum circuits superconducting diodes
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Exploring the optimal nitrogen threshold for global grassland restoration
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作者 Qi Zhang Fu Chen +12 位作者 Zhanbin Luo Jun Fan Yanfeng Zhu Jing Ma Yongjun Yang Xi-en Long Alejandro Gonzalez-Ollauri Miao Gan Weihong Guo Yuxiang Ma Qiaoling Wang Shenglu Zhou Mingan Shao 《Geography and Sustainability》 2026年第1期66-81,共16页
Amid accelerating global land degradation,establishing high-efficiency ecological restoration principles and frameworks is crucial.Here,we explore the application of threshold effects in the ecological restoration pro... Amid accelerating global land degradation,establishing high-efficiency ecological restoration principles and frameworks is crucial.Here,we explore the application of threshold effects in the ecological restoration process based on field experiments and globally available experimental data from 173 sites.Combining data integration analysis and meta-analysis,we collectively verified the universality of threshold effects in grasslands.The global grasslands’average nitrogen application threshold is 3.78 g·m^(-2)·yr^(−1),while the threshold value of degraded grassland(3.65 g·m^(-2)·yr^(−1))is lower than that of nondegraded grassland(5.90 g·m^(-2)·yr^(−1)).The low nitrogen-driven thresholds are affected by degradation status,climate(precipitation and temperature),and other site conditions,but not fertilization forms.Independent experiments further demonstrated that an increase in soil moisture content can lead to the disappearance of nitrogen threshold effects,revealing that ecological threshold effects are influenced by ecosystem stress factors.Following the significant increase in plant biomass triggered by the nitrogen threshold,the ecosystem undergoes systemic improvement.Soil organic carbon,urease activity,soil microbial diversity,and other soil properties are significantly enhanced.Soil nitrogen cycle-related microbial communities and soil physicochemical attributes are significantly activated.The results indicate that a threshold response pattern may develop before nitrogen saturation is reached,and low nitrogen input can boost productivity and improve the plant-soil-microbe system.Our findings reveal a nonprogressive path of restoration in degraded ecosystems,and thus,restoration based on threshold effects can offer an efficient and safe solution to combat ecological degradation. 展开更多
关键词 Ecological restoration Thresholds effect GRASSLAND NITROGEN META-ANALYSIS
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Calenduloside E produced by Bifidobacterium animalis B960 increases glibenclamide efficacy and alleviates drug-induced adverse effects in a type 2 diabetes model
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作者 Siyuan Shen Liting Lu +4 位作者 Haiyang Tu Shuaiming Jiang Zeng Zhang Zhe Han Jiachao Zhang 《Science Bulletin》 2026年第3期520-524,共5页
Concerns about the long-term safety and efficacy of glibenclamide(GLIB),a type 2 diabetes mellitus(T2DM)treatment,have been reported[1].Recent evidence indicates the gut microbiota composition significantly affects ho... Concerns about the long-term safety and efficacy of glibenclamide(GLIB),a type 2 diabetes mellitus(T2DM)treatment,have been reported[1].Recent evidence indicates the gut microbiota composition significantly affects host glucose metabolism and drugbioavailability,increasingthe efficacy of T2DM therapy[2].In this context,probiotic-drug coadministration,an emerging adjunct approach for treating metabolic diseases,improves therapeutic outcomes and ameliorates side effects[3]. 展开更多
关键词 treating metabolic diseasesimproves type diabetes mellitus t dm treatmenthave bifidobacterium animalis B adjunct approach calenduloside E glibenclamide efficacy ameliorates side effects drug induced adverse effects
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