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Dynamics of the perturbed Calogero-Moser system:well-posedness,stability and blow up
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作者 LIU Qianle WANG Zhong ZHU Weipeng 《中山大学学报(自然科学版)(中英文)》 北大核心 2026年第1期157-168,共12页
We investigate a class of non-integrable two-particle Calogero-Moser systems modulated by a power-law external potential.The local well-posedness of the Cauchy problem is established under the strict initial separatio... We investigate a class of non-integrable two-particle Calogero-Moser systems modulated by a power-law external potential.The local well-posedness of the Cauchy problem is established under the strict initial separation condition for the particles.For suitably prepared initial configurations,local solutions can be extended globally via energy conservation;conversely,negative energy conditions induce(in)finite-time blowup.The linear(in)stability of stationary solutions is analyzed,with their energy serving as a threshold.Numerical investigations employ a fourth-order Runge-Kutta scheme with adaptive step-size control.Simulations demonstrate that the trajectories either converge to steady states or exhibit blowup,depending on the power exponent α and initial conditions.Increasingαaccelerates the convergence rate and dampens oscillatory dynamics,promoting a transition from periodic behavior to static equilibrium. 展开更多
关键词 Calogero-Moser system WELL-POSEDNESS blow up STABILITY
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Systematic evaluation of reference gene stability across tissues and sexes in cuttlefish(Sepiella japonica)
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作者 LI Shuang GU Min +5 位作者 YE Xiaowen YE Bin LIU Siyu YU Jia ZHOU Xu CHI Changfeng 《水产学报》 北大核心 2026年第2期26-49,共24页
Quantitative real-time PCR(qPCR)is widely used for gene expression analysis,but its accuracy critically depends on stable internal reference genes for normalization.In marine invertebrates,especially non-model taxa su... Quantitative real-time PCR(qPCR)is widely used for gene expression analysis,but its accuracy critically depends on stable internal reference genes for normalization.In marine invertebrates,especially non-model taxa such as cephalopods,systematic evaluation of reference genes is limited,leading to potential bias.The cuttlefish Sepiella japonica is ecologically and economically important in China,yet previous molecular studies have often relied on single unvalidated reference genes,which may compromise data reliability.This study aimed to systematically evaluate the stability of five commonly used reference genes(18S,ef-1α,ef-1γ,gapdh,andβ-actin)across multiple tissues and sexes of S.japonica,and to identify the most suitable reference genes and optimal number for qPCR normalization.Fifteen to sixteen tissue types were collected from ten healthy adults(five males and five females).Total RNA was extracted,reverse-transcribed,and analyzed by qPCR.Gene stability was assessed using four algorithms(geNorm,NormFinder,BestKeeper,andΔCt)integrated with RefFinder,and the optimal gene number was determined using geNorm pairwise variation(V_(n/n+1)<0.15).Four transcriptome-derived genes(creld2,cd109,acy1,and miox)were used for validation.The C_(t)values of the five genes ranged from 15.47 to 20.83.β-actin and gapdh showed pronounced variability in expression stability among tissues and sexes,indicating their limited suitability for normalization.18S exhibited the highest expression(mean C_(t):15.47-16.29)and lowest variability but displayed sex-biased expression,whereas ef-1αand ef-1γremained consistently stable across most tissues in both sexes,with ef-1αbeing the most robust and showing no sex-related bias.Although specific rankings varied among tissues and sexes,the comprehensive results indicated that ef-1αand ef-1γpossessed the highest overall stability,followed by 18S,whileβ-actin and gapdh were the least stable.The final comprehensive rankings were ef-1γ>ef-1α>18S>gapdh>β-actin(male)and ef-1α>ef-1γ>18S>gapdh>β-actin(female).geNorm analysis(V2/3<0.15)indicated that two genes,mainly ef-1αand ef-1γ,were generally sufficient for reliable normalization in most tissues.Validation confirmed that normalization using the stable ef-1αand ef-1γaccurately reflected the expression differences among tissues,whereasβ-actin and gapdh can bias or confound statistical analyses.ef-1αand ef-1γare identified as the most reliable reference gene combination for qPCR analysis in S.japonica,while 18S can serve as an auxiliary gene for within-sex comparisons.The use ofβ-actin or gapdh alone is not recommended.This study establishes a systematic framework for selecting reliable reference genes in S.japonica,thereby facilitating robust qPCR normalization and providing a foundation for future gene expression research in S.japonica and other cephalopods. 展开更多
关键词 Sepiella japonica reference genes qPCR expression stability RefFinder
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Preparation of Ultrafine Copper Powders by Ethanol Solvothermal Method and Properties Study
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作者 XU Yite ZHANG Xiang +6 位作者 HE Junpeng WANG Keke CAO Lei ZHU Qian LIU Baixiong LIU Jianfeng XIONG Shixian 《有色金属(中英文)》 北大核心 2026年第1期31-39,共9页
The present work provides a facile and efficient method for producing ultrafine copper powders.Ultrafine copper powders were synthesized through a solvothermal method,utilizing ethanol both as a solvent and a reducing... The present work provides a facile and efficient method for producing ultrafine copper powders.Ultrafine copper powders were synthesized through a solvothermal method,utilizing ethanol both as a solvent and a reducing agent.Specifically,by exploiting the weak reducing property of ethanol,the copper precursor is first converted to copper oxide and then further reduced to cuprous oxide and pure copper.Such a method can effectively control the morphology and particle size of the copper powder,reduce particle aggregation,and enhance oxidation resistance.It is cost-effective and produces fewer toxic by-products.Spherical copper particles with an average particle size of about 180 nm were obtained.The initial oxidation temperature is approximately 150℃,and the resulting copper powders can be stored stably under ambient conditions for at least 5 months,demonstrating excellent oxidation resistance and thermal stability. 展开更多
关键词 alcohol-solvent heat ultrafine copper powder oxidation resistance thermal stability
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Ecological Dynamics of a Logistic Population Model with Impulsive Age-selective Harvesting
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作者 DAI Xiangjun JIAO Jianjun 《应用数学》 北大核心 2026年第1期72-79,共8页
In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asy... In this paper,we establish and study a single-species logistic model with impulsive age-selective harvesting.First,we prove the ultimate boundedness of the solutions of the system.Then,we obtain conditions for the asymptotic stability of the trivial solution and the positive periodic solution.Finally,numerical simulations are presented to validate our results.Our results show that age-selective harvesting is more conducive to sustainable population survival than non-age-selective harvesting. 展开更多
关键词 The logistic population model Selective harvesting Asymptotic stability EXTINCTION
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Manganese‑doped poly(1,5‑diaminonaphthalene)based high‑performance supercapacitors
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作者 XU Mengying LI Wen +5 位作者 MEI Junzhong ZHANG Cheng Palanisamy Kannan LU Lei ZHANG Lianpeng WANG Peng 《无机化学学报》 北大核心 2026年第2期387-397,共11页
Herein,manganese(Mn)‑doped poly(1,5‑diaminonaphthalene)(PN)electrode material(Mn@PN)was synthesized via chemical oxidative polymerization.The material′s distinctive vesicular architecture enables rapid ion transport ... Herein,manganese(Mn)‑doped poly(1,5‑diaminonaphthalene)(PN)electrode material(Mn@PN)was synthesized via chemical oxidative polymerization.The material′s distinctive vesicular architecture enables rapid ion transport while maintaining the structural stability of the electrode under continuous charge‑discharge cycles.Electrochemical characterization under a three‑electrode system revealed exceptional rate capability:Mn@PN delivered an ultrahigh specific capacitance of 10318 F·g^(-1) at a low current density of 3 A·g^(-1) and retained 9415 F·g^(-1)(91.2%retention compared to the value at 3 A·g^(-1))even at an ultrahigh current density of 50 A·g^(-1).Moreover,the material exhibited 97.4%capacitance retention after 9000 cycles at 30 A·g^(-1),corresponding with a low capacitance decay rate of 0.003‰per cycle,significantly outperforming conventional conductive polymers like polyaniline(PANI).An asymmetric supercapacitor assembled with Mn@PN as the positive electrode(Mn@PN||AC)achieved an energy density of 328 Wh·kg^(-1) at 15 A·g^(-1) and retained 80.7%of its initial specific capacitance after 4000 cycles at 20 A·g^(-1). 展开更多
关键词 poly(1 5‑diaminonaphthalene) transition metal long‑cycle stability SUPERCAPACITOR
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U.K.Prime Minister’s China Visit Signals a Pragmatic Turn in Bilateral Relations
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作者 JOHN QUELCH 《China Today》 2026年第3期20-22,共3页
British Prime Minister Keir Starmer’s visit to China underscores economic cooperation and strategic stability amid global uncertainties.U.K.Prime Minister Keir Starmer’s visit to China in January marks a significant... British Prime Minister Keir Starmer’s visit to China underscores economic cooperation and strategic stability amid global uncertainties.U.K.Prime Minister Keir Starmer’s visit to China in January marks a significant shift of Britain toward a more pragmatic and stability-oriented approach in Sino-British relations.After years of political tensions and limited high-level engagement,this trip underscores London’s intent to rebuild ties based on mutual economic and strategic interests. 展开更多
关键词 economic cooperation economic cooperation strategic stability bilateral relations UK strategic stability China rebuild ties political tensions
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Underscoring the polyimide-linkage in covalent organic frameworks and related applications
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作者 Qi Li Minqiao Liang +5 位作者 Huifen Zhuang Zhengyang Chen Yuxiang Jiang Xiaofei Chen Yifa Chen Ya-Qian Lan 《Chinese Chemical Letters》 2026年第2期6-18,共13页
Polyimide-linkage covalent organic frameworks(PI-COFs),as a subclass of the COFs material family,featuring the unique combination of excellent thermal stability of polyimide,tunable pore sizes,as well as high crystall... Polyimide-linkage covalent organic frameworks(PI-COFs),as a subclass of the COFs material family,featuring the unique combination of excellent thermal stability of polyimide,tunable pore sizes,as well as high crystallinity and surface area of COFs,are expected to be a novel type of promising crystalline porous material with potential applications in adsorption and separation,catalysis,chemical sensing,and energy storage.Therefore,it is increasingly important to summarize polyimide-linkage in COFs and related applications and provide in-depth insight to accelerate future development.In this review,we offer a comprehensive overview of recent advancements in PI-COFs,emphasizing their synthesis methods,design principles and applications.Finally,our brief outlooks on the current challenges and future developments of PI-COFs are provided.Overall,this review aims to guide the recent and future development of PI-COFs. 展开更多
关键词 Covalent organic frameworks Polyimide-linkage Heteroatomic sites Chemical stability Thermal stability
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Hydrothermal conversion from hydrogarnet to hydroandradite based on alumina recovery from red mud
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作者 Hong-fei WU Xiao-lin PAN +3 位作者 Ji-long LIU Feng QIU Tun HE Hai-yan YU 《Transactions of Nonferrous Metals Society of China》 2026年第1期309-322,共14页
To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM ... To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM methods,and a novel hydrothermal process based on the conversion principle was finally proposed.The crystal structure simulation shows that the HA with varied silicon saturation coefficients is more stable than HG,and the HA with a high iron substitution coefficient is more difficult to be converted from HG.The(110)plane of Fe_(2)O_(3) is easier to combine with HG to form HA,and the binding energy is 81.93 kJ/mol.The effects of raw material ratio,solution concentration and hydrothermal parameters on the conversion from HG to HA were revealed,and the optimal conditions for the alumina recovery were obtained.The recovery efficiencies of alumina and Na_(2)O from the RM are 63.06%and 97.34%,respectively,and the Na_(2)O content in the treated RM is only 0.13%. 展开更多
关键词 HYDROGARNET hydroandradite structural stability hydrothermal conversion red mud
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Time-dependent ground stability of inclined backfilled stope characterized by creep behavior
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作者 Ruofan Wang Yujie Zhu +3 位作者 Lang Liu Mengbo Zhu Baoxu Yan Hao Cui 《International Journal of Minerals,Metallurgy and Materials》 2026年第2期479-491,共13页
Backfill is routinely adopted as a ground support measure for underground mines.However,ground stability enhancement by backfill has received limited research attention.This is likely to be because of the conventional... Backfill is routinely adopted as a ground support measure for underground mines.However,ground stability enhancement by backfill has received limited research attention.This is likely to be because of the conventional assumption that the fill material exhibits a significantly lower stiffness than the host rocks.Significantly,a recent pioneering work revealed the time-dependent ground stability around a backfilled stope with vertical walls through numerical modeling.In practice,underground stopes typically exhibit a higher or lower degree of inclination.This alters the stress state in peripheral rocks and may induce severe instability and dilution,particularly in stope-hanging walls.Hence,it is imperative to analyze the time-dependent ground stability of inclined backfilled stopes for backfill structure design.Therefore,comprehensive numerical simulations were performed using FLAC3D to address this knowledge deficiency by incorporating a coupled analysis of the backfill consolidation behavior and long-term creep deformation in surrounding rocks.The ground stability was evaluated based on the confinement effectiveness,strength-stress ratio,stress path relative to the yield surface,and time-dependent stress redistribution in the rocks.A parametric study revealed that the inclination angle of the backfilled stope reduced the confinement effectiveness in the host rocks when the wall creep was minor.This exacerbated the rock mass sloughing potential.However,a backfilled stope with a shallower dip angle achieved superior ground stability enhancement when the creep deformation was substantial,by applying a more significant compression on the backfill and effectively mobilizing its passive support performance during consolidation.Additional simulations were conducted to analyze the effects of stope height and width,mine depth,mechanical properties of rocks,backfill compressibility,and filling gap on the time-dependent stress redistribution and stability around the inclined backfilled stope. 展开更多
关键词 inclined backfilled stope ground stability time-dependency creep CONSOLIDATION
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Colour Changes of Wood Veneer as a Function of Heat Treatment
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作者 Hikaru Kobori Emilia-Adela Manea Salca +3 位作者 Tetsuya Inagaki Shigehiko Suzuki Sahriyanti Saad Aujchariya Chotikhun 《Journal of Renewable Materials》 2026年第2期50-64,共15页
Heat treatment is applied towood to improve various properties of thematerial.Thepresent study focuses on the colour changes of wood veneer samples due to heat treatment.Native wood species fromJapan and Europe,such a... Heat treatment is applied towood to improve various properties of thematerial.Thepresent study focuses on the colour changes of wood veneer samples due to heat treatment.Native wood species fromJapan and Europe,such as Japanese oak(Quercus mongolica var.crispula),field maple(Acer campestre)and Scots pine(Pinus sylvestris)were used in the experiments.A laboratory-type oven was used to apply the heat at a temperature of 190○C,in the presence of oxygen,for different periods,gradually increasing from 5 to 40 min.The CIELab system(a colour space defined by the International Commission on Illumination)and Near Infrared Spectroscopy(NIR)were employed to evaluate the colour modifications on the samples.As expected,the heat treatment affected the colour of the samples.The lightness index decreased across the three wood species during the treatment.The chroma coordinates changed for pine and maple,while little change occurred in Japanese oak.The overall total colour differences reached their maximum at the final 40-min interval for all wood types.Based on the NIR evaluation,it was found that drastic thermal denaturation of cellulose was unlikely to occur,and the changes in the intermolecular interaction of water affected the colour of the specimens.The data and information of this study could be useful for industrial applications where the veneer of such species is desired.Such heat-treated veneers can be considered as value-added products in furniture manufacturing as well as restoration of furniture units where such veneer is used as an overlay. 展开更多
关键词 Colour stability Japanese oak MAPLE PINE heat treatment
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Innovative Strategies to Overcome Stability Challenges of Single‑Atom Nanozymes
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作者 Rong Guo Qiuzheng Du +3 位作者 Yaping He Haoan Wu Yu Zhang Ziwei Jing 《Nano-Micro Letters》 2026年第3期725-756,共32页
Single-atom nanozymes(SAzymes)exhibit exceptional catalytic efficiency due to their maximized atom utilization and precisely modulated metalcarrier interactions,which have attracted significant attention in the biomed... Single-atom nanozymes(SAzymes)exhibit exceptional catalytic efficiency due to their maximized atom utilization and precisely modulated metalcarrier interactions,which have attracted significant attention in the biomedical field.However,stability issues may impede the clinical translation of SAzymes.This review provides a comprehensive overview of the applications of SAzymes in various biomedical fields,including disease diagnosis(e.g.,biosensors and diagnostic imaging),antitumor therapy(e.g.,photothermal therapy,photodynamic therapy,sonodynamic therapy,and immunotherapy),antimicrobial therapy,and anti-oxidative stress therapy.More importantly,the existing challenges of SAzymes are discussed,such as metal atom clustering and active site loss,ligand bond breakage at high temperature,insufficient environment tolerance,biosecurity risks,and limited catalytic long-term stability.Finally,several innovative strategies to address these stability concerns are proposed—synthesis process optimization(space-limited strategy,coordination site design,bimetallic synergistic strategy,defect engineering strategy,atom stripping-capture),surface modification,and dynamic responsive design—that collectively pave the way for robust,clinically viable SAzymes. 展开更多
关键词 Single-atom nanozymes Clinical translation Stability issues Innovative strategies BIOCOMPATIBILITY
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Nature-Inspired Redox Shuttle with Regenerable Antioxidant for Efficient All-Perovskite Tandem Solar Cells
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作者 Rui Meng Liming Du +12 位作者 Can Li Zhi Wan Jishan Shi Yueying Zhang Wenfeng Liu Chongyang Zhi Chunmei Jia Lili Tan Chuanxiao Xiao Xian-Zong Wang Lin Song Xingyu Gao Zhen Li 《Nano-Micro Letters》 2026年第5期590-606,共17页
Pb-Sn mixed perovskite solar cells(PSCs)are crucial components for realizing efficient all-perovskite tandem devices.However,their efficiency and stability are severely limited by oxidative degradation(Sn^(4+)formatio... Pb-Sn mixed perovskite solar cells(PSCs)are crucial components for realizing efficient all-perovskite tandem devices.However,their efficiency and stability are severely limited by oxidative degradation(Sn^(4+)formation)and metallic defects(Sn^(0)/Pb^(0)).In addition,the rapid and uncontrolled Sn^(2+)nucleation kinetics result in nonuniform crystallization.Herein,we introduce a natural redox shuttle glutathione(GSH)in Pb-Sn mixed PSCs,achieving regenerable antioxidation and crystallization regulation simultaneously.The reversible redox reactions between GSH and glutathione disulfide(GSSG)enable the self-healing of Sn^(4+)and Sn^(0)/Pb^(0)impurities,creating a regenerable antioxidation protective shell at the perovskite interfaces.Meanwhile,the strong coordination between GSH and perovskite regulates the crystallization process,optimizing the nucleation and crystallization kinetics.Furthermore,the GSH incorporation creates a high-quality charge separation junction at the perovskite/hole transport layer,facilitating carrier separation and extraction.The optimized Pb-Sn PSCs exhibit impressive power conversion efficiencies(PCEs)of up to 23.71%.The champion all-perovskite tandem PSCs with GSH achieve a PCE of 28.49%and retain 90%of the initial PCE after 560 h of continuous illumination.This work establishes a new nature-inspired redox shuttling strategy and elucidates its working mechanism,advancing the development of efficient and stable all-perovskite tandem solar cells. 展开更多
关键词 Pb-Sn perovskite Redox shuttle Crystallization regulation All-perovskite tandem Stability
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Process analysis of nuclear hydrogen production via intermediate temperature SOEC electrolysis
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作者 Qing Shao Yue Lu +7 位作者 Dun Jin Ling-Hong Luo Xiu-Lin Wang Hui-Chao Yao Ruo-Yun Dai Cheng-Zhi Guan Guo-Ping Xiao Jian-Qiang Wang 《Nuclear Science and Techniques》 2026年第2期122-133,共12页
When the operating temperature of a solid oxide electrolysis cell(SOEC)is lower than the outlet temperature of a nuclear reactor,the reactor can be directly coupled with the SOEC as a high-temperature heat source.Howe... When the operating temperature of a solid oxide electrolysis cell(SOEC)is lower than the outlet temperature of a nuclear reactor,the reactor can be directly coupled with the SOEC as a high-temperature heat source.However,the key to the efficiency and return on investment of this hybrid energy system lies in the expected lifetime of the SOEC.This study assessed Ni-YSZ|YSZ|GDC|LSC fuel electrode support cells’long-term stability during electrolysis at 650℃with a current density of−0.5Acm^(−2)over 1818 h.The average voltage degradation rate of 2.63%kh^(−1)unfolded in two phases:an initial rapid decay(90 to 1120 h at 3.58%kh^(−1))and a stable decay(1120 to 1818 h at 2.14%kh^(−1)),emphasizing SOECs’probability coupling with nuclear reactors at 650℃.Post-1818-hour electrolysis revealed nickel particle formation associated with Ni(OH)_(x)diffusion and re-deposition,alongside a strontium-containing layer causing interface cracking.Despite minimal strontium segregation in the EDS,XPS data indicated surface segregation of Sr.This study provides crucial insights into prolonged SOEC operation,highlighting both its potential and challenges. 展开更多
关键词 Nuclear hydrogen production SOEC STABILITY Intermediate temperature
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Global Stability of Traveling Wavefronts for a Belousov-Zhabotinsky Model with Mixed Nonlocal and Degenerate Diffusions
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作者 Yuting YANG Guobao ZHANG 《Journal of Mathematical Research with Applications》 2026年第1期87-102,共16页
In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocal... In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocally diffusive species and degenerately diffusive species.We prove that the traveling wavefronts are exponentially stable,when the initial perturbation around the traveling waves decays exponentially as x→-∞,but in other locations,the initial data can be arbitrarily large.The adopted methods are the weighted energy with the comparison principle and squeezing technique. 展开更多
关键词 Belousov-Zhabotinsky model nonlocal diffusion stability comparison principle weighted energy
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Stability analysis of soft-hard interbedded anti-inclined rock slope under rainfall based on deformation compatibility
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作者 GUO Jianjun WU Zhenwei +2 位作者 CAO Heng ZHANG Wei WANG Junjie 《Journal of Mountain Science》 2026年第1期380-393,共14页
Rock slope instability is a prevalent geological hazard that imposes significant adverse impacts on engineering activities.Although existing studies have focused on homogeneous rock slopes,the theoretical models for q... Rock slope instability is a prevalent geological hazard that imposes significant adverse impacts on engineering activities.Although existing studies have focused on homogeneous rock slopes,the theoretical models for quantifying the stability of softhard interbedded anti-inclined slopes remain underdeveloped,primarily due to the complex force transfer mechanisms involved.This study proposed a novel theoretical model for the stability analysis of soft-hard interbedded anti-inclined slopes under rainfall conditions.The framework models stratified rock layers as layered cantilever beams with material heterogeneity.Based on the principle of deformation compatibility,it comprehensively accounted for interlayer force transfer and strength degradation resulting from differential deformations among rock layers.Furthermore,it integrated the critical instability length induced by the self-weight of rock layers to determine the fracture depth.The proposed method was validated against engineering case studies and physical model tests,with error falling within an acceptable range.Compared to existing theoretical methods,the proposed method provided a more realistic representation of the slope's stress field.The analysis results demonstrate that rainfall not only reduces the inclination angle of the failure surface but also leads to an approximate 30%decrease in the safety factor.The proposed theoretical model is particularly useful for quickly calculating the stability of soft-hard interbedded anti-inclined rock slope under rainfall conditions,compared to complex and time-consuming numerical simulation calculations. 展开更多
关键词 Soft-hard interbedded Anti-inclined slope RAINFALL Stability analysis Theoretical method
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How different thinning can improve carbon sequestration,carbon stock and mechanical stability in peri-urban mixed forest stands:a study case in Mediterranean environment
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作者 Ugo Chiavetta Paolo Cantiani 《Journal of Forestry Research》 2026年第1期138-151,共14页
Peri-urban plantations in the Mediterranean are often degraded due to human inactivity and climate change,leading to a loss of ecosystem services and biodiversity.This study investigates the impact of different thinni... Peri-urban plantations in the Mediterranean are often degraded due to human inactivity and climate change,leading to a loss of ecosystem services and biodiversity.This study investigates the impact of different thinning practices on carbon sequestration and tree stability in a degraded periurban plantation in the Italian Apennines,six years after thinning.Three treatments were compared:(a)moderate thinning from below(-25%biomass),representing the typical practice;(b)intense selective thinning(-35%biomass),representing an innovative approach;and(c)no management as the control.Growth projections were used to estimate carbon recovery for these treatments,based on site-specific models calibrated with real data.The results show that both thinning approaches increased carbon sequestration over time,with the innovative thinning achieving a 7%higher annual carbon sequestration rate than traditional thinning and 8%more than the control.Estimated payback times were9 years for recovering the harvested volume in both thinning approaches,10 years for innovative thinning to surpass traditional thinning,17 years for innovative thinning to surpass the control,and 24 years for traditional thinning to surpass the control.Additionally,tree mechanical stability improved significantly in both thinning treatments after two years,with further increases observed in the innovative thinning group after six years.These results suggest that selective thinning can accelerate forest recovery and carbon sequestration,especially in areas with high stem density,where it can reduce the negative impacts of tree mortality and deadwood accumulation.However,careful planning is required to mitigate potential short-term stability is sues,particularly in challenging environments(e.g.,windy conditions,steep slopes).Forest management strategies should therefore aim to balance growth,carbon storage,and tree stability,considering both long-term sustainability and local environmental conditions.The findings are particularly relevant for current climate change mitigation strategies,emphasizing that thinning should be carefully tailored to forest type and conditions to maximize benefits in carbon credit generation and sustainable forest management practices. 展开更多
关键词 Peri-urban plantations Carbon sequestration THINNING Payback time Tree mechanical stability
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Numerical study of material contrast effect on damage and instability in wellbores under repeated drill string impacts
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作者 Hadi Haghgouei Anders Nermoen Alexandre Lavrov 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期831-860,共30页
Drill string vibration during drilling plays a vital and potentially decisive role in maintaining wellbore stability,as repeated impacts may lead to fatigue and borehole collapse.While drilling through geological laye... Drill string vibration during drilling plays a vital and potentially decisive role in maintaining wellbore stability,as repeated impacts may lead to fatigue and borehole collapse.While drilling through geological layers,a material contrast may act as a localization point for wellbore damage.The hypothesis tested in this paper is that wellbore instability is focused on the boundary between the layers and that mechanical contrasts accelerate the wellbore collapse.In this study,an elastic-plastic damage model was employed to investigate the effects of repeated mechanical impacts on wellbore stability.A 2-dimensional(2D)model of a wellbore surrounded by contrasting materials was developed,and the accumulated damage caused by repeated lateral impacts was monitored.It was found that damage develops not only around the wall of the wellbore but also along the material boundaries.A sensitivity analysis was carried out to identify the impact of contrasts in both elastic(Young's modulus and Poisson's ratio)and plastic(cohesion,friction angle,and dilation angle)parameters between layers.Four damage patterns were identifiedin the simulated models.The results also suggested that the number of impacts required to reach the critical damage was highly affected by the contrast in elastic parameters,while cohesion and friction angle contrasts had a lesser effect.Additionally,increasing the contrast in the dilation angle localized the damage,thus reducing the number of impacts required to trigger wellbore failure. 展开更多
关键词 Wellbore stability Material contrast Geological layer DRILLING Drill string Fatigue Cyclic load
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Prioritized Na^(+)Adsorption-Driven Cationic Electrostatic Repulsion Enables Highly Reversible Zinc Anodes at Low Temperatures
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作者 Guanchong Mao Pan Xu +4 位作者 Xin Liu Xingyu Zhao Zexiang Shen Dongliang Chao Minghua Chen 《Nano-Micro Letters》 2026年第2期306-319,共14页
Aqueous zinc metal batteries(AZMBs)are promising candidates for renewable energy storage,yet their practical deployment in subzero environments remains challenging due to electrolyte freezing and dendritic growth.Alth... Aqueous zinc metal batteries(AZMBs)are promising candidates for renewable energy storage,yet their practical deployment in subzero environments remains challenging due to electrolyte freezing and dendritic growth.Although organic additives can enhance the antifreeze properties of electrolytes,their weak polarity diminishes ionic conductivity,and their flammability poses safety concerns,undermining the inherent advantages of aqueous systems.Herein,we present a cost-effective and highly stable Na_(2)SO_(4)additive introduced into a Zn(ClO_(4))2-based electrolyte to create an organic-free antifreeze electrolyte.Through Raman spectroscopy,in situ optical microscopy,densityfunctional theory computations,and molecular dynamics simulations,we demonstrate that Na+ions improve low-temperature electrolyte performance and mitigate dendrite formation by regulating uniform Zn^(2+)deposition through preferential adsorption and electrostatic interactions.As a result,the Zn||Zn cells using this electrolyte achieve a remarkable cycling life of 360 h at-40℃ with 61% depth of discharge,and the Zn||PANI cells retained an ultrahigh capacity retention of 91%even after 8000 charge/discharge cycles at-40℃.This work proposes a cost-effective and practical approach for enhancing the long-term operational stability of AZMBs in low-temperature environments. 展开更多
关键词 Low-temperature resistant Organic-free additive Aqueous batteries High stability
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Stableδ-FA(Cs)PbI_(3)intermediate enables fabrication of large-area perovskite solar modules in ambient air
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作者 Chenyang Duan Ke Xiao +12 位作者 Yinke Wang Ye Liu Yameen Ahmed Zhentao Pang Wenjun Zhan Hongfei Sun Han Gao Haowen Luo Yuhong Zhang Xin Luo Yu Deng Makhsud I.Saidaminov Hairen Tan 《Science China Materials》 2026年第3期1456-1463,共8页
Fabrication of large-area perovskite solar modules under ambient air conditions remains a critical challenge due to air sensitivity of perovskite intermediate phases during crystallization.Here,we introduce 2-iodoimid... Fabrication of large-area perovskite solar modules under ambient air conditions remains a critical challenge due to air sensitivity of perovskite intermediate phases during crystallization.Here,we introduce 2-iodoimidazole(IIZ)into the perovskite precursor,enabling the formation of an air-stable pureδ-phase intermediate,which,upon annealing,fully transforms into a highly orientedα-phase perovskite film with reduced defects and variability.Leveraging this approach,we achieve a stabilized power conversion efficiency of 20.9%for 927.5 cm^(2)perovskite solar modules with high reproducibility.The encapsulated modules meet stringent international photovoltaic testing standards(IEC61215:2021),demonstrating excellent stability under continuous operation,thermal cycling(-40 to 85℃)and damp heat(85℃ and 85%relative humidity). 展开更多
关键词 perovskite solar modules intermediate phases ambient fabrication scalable fabrication stability
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Modeling Hepatitis B and Alcohol Effects on Liver Cirrhosis Progression
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作者 Zia Ur Rahman Nigar Ali +4 位作者 Dragan Pamucar Imtiaz Ahmad Haci Mehmet Baskonus Naseer Ul Haq Zeeshan Ali 《Computer Modeling in Engineering & Sciences》 2026年第1期954-988,共35页
Hepatitis B Virus(HBV)infection and heavy alcohol consumption are the two primary pathogenic causes of liver cirrhosis.In this paper,we proposed a deterministic mathematical model and a logistic equation to investigat... Hepatitis B Virus(HBV)infection and heavy alcohol consumption are the two primary pathogenic causes of liver cirrhosis.In this paper,we proposed a deterministic mathematical model and a logistic equation to investigate the dynamics of liver cirrhosis progression as well as to explain the implications of variations in alcohol consumption on chronic hepatitis B patients,respectively.The intricate interactions between liver cirrhosis,recovery,and treatment dynamics are captured by the model.This study aims to show that alcohol consumption by Hepatitis B-infected individuals accelerates liver cirrhosis progression while treatment of acutely infected individuals reduces it.We proved that a unique solution of the proposed model exists,which is positive and bounded.Using the next-generation matrix approach,two basic reproductive numbers R_(A_(0))and R_(A_(max))are calculated to identify future recurrence.The equilibrium points are calculated,and both equilibria are proved locally and globally asymptotically stable when R_(0)is below and above one,respectively.It is shown that bifurcation exists at R_(0)=1 and a detailed proof for forward bifurcation is given.Furthermore,we performed the sensitivity analysis of the model parameters on R_(0).For the confirmation of analytical work,we performed numerical simulations,and the results indicate that the treatment and the inhibitory effects reduce the risk of developing liver cirrhosis in individuals,while heavy alcohol consumption accelerates markedly the liver cirrhosis progression in patients with chronic hepatitis B. 展开更多
关键词 Liver cirrhosis deterministic model saturated incidence rate STABILITY forward bifurcation
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