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Estimates for p-adic fractional integral operator with rough kernels on grand p-adic Herz-type spaces
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作者 XIA Xiaoxi ZHOU Jiang 《中山大学学报(自然科学版)(中英文)》 北大核心 2026年第2期153-159,共7页
The goal of this paper is to establish the boundedness of the p-adic fractional integral operator with rough kernel I_(β,Ω′)^(p)and its commutators generated by b∈Λ_(γ)(Q_(p)^(n))(0<γ<1)and the I_(β,Ω′... The goal of this paper is to establish the boundedness of the p-adic fractional integral operator with rough kernel I_(β,Ω′)^(p)and its commutators generated by b∈Λ_(γ)(Q_(p)^(n))(0<γ<1)and the I_(β,Ω′)^(p) on grand p-adic Herz spaces. 展开更多
关键词 Lipschitz spaces grand p-adic Herz spaces p-adic fractional integral operator COMMUTATORS
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Lipschitz Estimates for the Commutators of Fractional Hardy and Hardy-Littlewood-Pólya Operators on Grand p-adic Variable Herz Spaces
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作者 常云鹏 武江龙 《数学进展》 北大核心 2026年第2期419-430,共12页
In this article,we prove the boundedness for commutators of fractional Hardy and Hardy-Littlewood-Pólya operators on grand p-adic variable Herz spaces,where the symbols of the commutators belong to Lipschitz spaces.
关键词 p-adic field fractional Hardy operator Hardy-Littlewood-Pólya operator grand variable Herz space commutator
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VOF-Based Simulation of Turbulent Air-Water Flow over Gravel Beds in Open Channels
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作者 Abdullah Abdullah Ghulam Mohi Ud Din +2 位作者 Tipu Sultan Muhammad Aleem Muhammad Shareef Shazil 《Fluid Dynamics & Materials Processing》 2026年第3期18-35,共18页
Turbulent flow over gravel beds in open channels is a fundamental yet complex problem in hydraulic engineering,as flow behavior is highly sensitive to channel geometry and bed roughness.In this study,the Volume of Flu... Turbulent flow over gravel beds in open channels is a fundamental yet complex problem in hydraulic engineering,as flow behavior is highly sensitive to channel geometry and bed roughness.In this study,the Volume of Fluid(VOF)method coupled with the standard k-εturbulence model is employed to simulate air-water interactions over gravel beds,with open boundary conditions capturing realistic channel-atmosphere interactions.Numerical simulations are performed to examine how channel design influences the relationship between the friction factor(f)and the Reynolds number(RN).Velocity and VOF contours indicate peak flow near the inlet,with a maximum velocity of 0.64 m/s.The simulations show strong agreement with theoretical predictions,yielding a correlation coefficient of 0.99 for RN,while f and Chezy’s coefficient(C)reach 0.75 and 0.71,respectively.Comparison with experimental measurements shows deviations of approximately 17% for RN,25% for f,and 12% for C.Moreover,further analysis confirms an inverse linear relationship between f and RN,in accordance with classical models such as Bazin’s curves,the Colebrook equation,and Moody’s approximation.Overall,the results demonstrate that the proposed numerical framework reliably captures flow dynamics over gravel beds,offering a robust tool for hydraulic design and performance assessment of open channels. 展开更多
关键词 Friction factor Reynolds number gravel bed open channel vof modelling
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Fractional calculus approach to RT-IN enzymatic competition in modulating HIV replication dynamics
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作者 Tushar Ghosh Oluwole Daniel Makinde +1 位作者 WANG Shu Priti Kumar Roy 《Applied Mathematics(A Journal of Chinese Universities)》 2026年第1期225-254,共30页
HIV infection continues to pose a significant global health challenge,with subSaharan Africa bearing a disproportionate burden.The replication cycle of HIV is fundamentally driven by intricate molecular interactions.T... HIV infection continues to pose a significant global health challenge,with subSaharan Africa bearing a disproportionate burden.The replication cycle of HIV is fundamentally driven by intricate molecular interactions.This study investigates the competitive biochemical interplay between reverse transcriptase(RT)and integrase(IN)enzymes,employing a fractional calculus framework to model their mutual inhibitory effects.Through the application of fixed-point theory and Picard stability analysis,the existence,uniqueness,and stability of the fractional-order system are rigorously established.The role of RT-IN enzymatic competition in influencing HIV replication dynamics is elucidated through global sensitivity analysis using Latin Hypercube Sampling.Furthermore,the model incorporates memory-dependent characteristics by examining three distinct fractional operators,namely,the Caputo,Caputo-Fabrizio,and Atangana-Baleanu operators in the Caputo sense,thereby elucidating their respective influences on system behavior.The Atangana-Baleanu operator,in particular,demonstrates an enhanced capacity to capture the complex,synergistic processes underpinning HIV progression.This research provides a critical nexus between molecular virology and applied mathematics,offering foundational insights for the advancement of more precise and targeted therapeutic strategies against HIV. 展开更多
关键词 HIV biochemical interaction physical interaction fractional calculus Sumudu transformation LHS PRCC
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A Fractional-Order Study for Bicomplex Haemorrhagic Infection in Several Populations Conditions
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作者 Muhammad Farman Muhammad Hashir Zubair +2 位作者 Hua Li Kottakkaran Sooppy Nisar Mohamad Hafez 《Computer Modeling in Engineering & Sciences》 2026年第1期926-953,共28页
Lassa Fever(LF)is a viral hemorrhagic illness transmitted via rodents and is endemic in West Africa,causing thousands of deaths annually.This study develops a dynamic model of Lassa virus transmission,capturing the pr... Lassa Fever(LF)is a viral hemorrhagic illness transmitted via rodents and is endemic in West Africa,causing thousands of deaths annually.This study develops a dynamic model of Lassa virus transmission,capturing the progression of the disease through susceptible,exposed,infected,and recovered populations.The focus is on simulating this model using the fractional Caputo derivative,allowing both qualitative and quantitative analyses of boundedness,positivity,and solution uniqueness.Fixed-point theory and Lipschitz conditions are employed to confirm the existence and uniqueness of solutions,while Lyapunov functions establish the global stability of both disease-free and endemic equilibria.The study further examines the role of the Caputo operator by solving the generalized power-law kernel via a two-step Lagrange polynomial method.This approach offers practical advantages in handling additional data points in integral forms,though Newton polynomial-based schemes are generally more accurate and can outperform Lagrange-based Adams-Bashforth methods.Graphical simulations validate the proposed numerical approach for different fractional orders(ν)and illustrate the influence of model parameters on disease dynamics.Results indicate that increasing the fractional order accelerates the decline of Lassa fever in both human and rodent populations.Moreover,fractional-order modeling provides more nuanced insights than traditional integer-order models,suggesting potential improvements for medical intervention strategies.The study demonstrates that carefully chosen fractional orders can optimize convergence and enhance the predictive capacity of Lassa fever models,offering a promising direction for future research in epidemiological modeling. 展开更多
关键词 Lassa fever mathematical model caputo fractional operator lyapunov stability
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CT-derived fractional flow reserve combined with atherosclerotic extent to determine long-term outcomes in diabetic patients with coronary artery disease
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作者 Zhi-Qiang WANG Zhen-Nan LI +1 位作者 Zhi-Hui HOU Bin LU 《Journal of Geriatric Cardiology》 2026年第1期27-35,共9页
Background There is still limited data on predictive value of coronary computed tomography angiography(CCTA)–derived fractional flow reserve(CT-FFR) for long term outcomes. We examined the long-term prognostic value ... Background There is still limited data on predictive value of coronary computed tomography angiography(CCTA)–derived fractional flow reserve(CT-FFR) for long term outcomes. We examined the long-term prognostic value of CT-FFR combined with CCTA–defined atherosclerotic extent in diabetic patients with coronary artery disease(CAD).Methods A retrospective pooled analysis of individual patient data was performed. Deep-learning-based vessel-specific CTFFR was calculated. All patients enrolled were followed-up for at least 5 years. Predictive abilities for major adverse cardiac events(MACE) were compared among three models(model 1), constructed using clinical variables;model 2, model 1+CCTA–derived atherosclerotic extent(Leiden risk score);and model 3, model 2+CT-FFR.Results A total of 480 diabetic patients [median age, 61(55–66) years;52.9% men] were included. During a median follow-up time of 2197(2126–2355) days, 55 patients(11.5%) experienced MACE. In multivariate-adjusted Cox models, Leiden risk score(HR: 1.06;95% CI: 1.01–1.11;P = 0.013) and CT-FFR ≤ 0.80(HR: 6.54;95% CI: 3.18–13.45;P < 0.001) were the independent predictors. The discriminant ability was higher in model 2 than in model 1(C-index, 0.75 vs. 0.63;P < 0.001) and was further promoted by adding CT-FFR to model 3(C-index, 0.81 vs. 0.75;P = 0.002). Net reclassification improvement(NRI) was 0.19(P = 0.009) for model 2 beyond model 1. Of note, adding CT-FFR to model 3 also exhibited significantly improved reclassification compared with model 2(NRI = 0.14;P = 0.011).Conclusion In diabetic patients with CAD, CT-FFR provides robust and incremental prognostic information for predicting longterm outcomes. The combined model exhibits improved prediction abilities, which is beneficial for risk stratification. 展开更多
关键词 fractional flow reserve ct ffr coronary artery disease cad methods tomography angiography ccta derived coronary artery disease atherosclerotic extent fractional flow reserve diabetic patients coronary computed tomography angiography
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Molecular composition of water soluble fraction of petroleum products and crude oils:Insights into groundwater contamination potential and environmental forensics
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作者 Wang Yu Yuruo Wan +3 位作者 Wei Zhou Jiayi An Liting Tian Jie Ma 《Journal of Environmental Sciences》 2026年第1期437-444,共8页
Petroleum leakage is a major groundwater contamination source,with chemical composition of water soluble fractions(WSFs)from diverse oil sources significantly impacting groundwater quality and source identification.Th... Petroleum leakage is a major groundwater contamination source,with chemical composition of water soluble fractions(WSFs)from diverse oil sources significantly impacting groundwater quality and source identification.The aim of this study was to assess impact of 15 diverse oils on groundwater quality and environmental forensics based on oil-water equilibrium experiments.Our results indicate that contamination of groundwater by gasoline and naphtha is primarily attributed to volatile hydrocarbons,while pollution from diesel,kerosene,and crude oil is predominantly from non-hydrocarbons.Rapid determination of the extent of non-hydrocarbon pollution in WSFs was achieved through a new quantitative index.Gasoline and naphtha exhibited the highest groundwater contamination potential while kerosene and light crude oils were also likely to cause groundwater contamina-tion.Although volatile hydrocarbons in the WSFs of diesel and jet fuel do not easily exceed current regulatory standards,unregulated non-hydrocarbons may pose a more severe contamination risk to groundwater.Notably,the presence of significant benzene and toluene,hydrogenation and alkylation products(e.g.,C4-C5 alkylben-zenes,alkylindenes,alkyltetralins,and dihydro-indenes),cycloalkanes in WSFs can effectively be utilized for preliminary source identification of light distillates,middle distillates,and crude oils,respectively. 展开更多
关键词 Petroleum hydrocarbons Water soluble fraction Contaminated sites Groundwater contamination Source identification
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Prediction of lithium content in typical mountainous clay in Xinjiang,China using fractional derivatives and feature extraction
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作者 JIANG Guo CUI Shichao +6 位作者 CHEN Xi CHEN Xi WANG Jinlin CHEN Tao ZHOU Shuguang ZHANG Zhengfeng XU Xiaozhi 《Journal of Mountain Science》 2026年第2期545-558,共14页
Lithium(Li)is an‘emerging'environmental pollutant,especially in soil,which is a great concern because it can endanger human health through the food chain.Compared with traditional chemical analyses,hyperspectral ... Lithium(Li)is an‘emerging'environmental pollutant,especially in soil,which is a great concern because it can endanger human health through the food chain.Compared with traditional chemical analyses,hyperspectral techniques have achieved many exciting results in soil metal monitoring due to their advantages of being fast and non-destructive.However,insufficient attention has been paid to lithium in soil,and the feasibility of its estimation using hyperspectral techniques needs to be investigated.We studied 97 soil samples from claytype lithium mines in the Ertanggou area of the East Tianshan Mountains of Xinjiang to explore the effects of spectral resolution,fractional order derivatives(FOD),and characteristic band selection on the estimation accuracy of clay Li content,to obtain a fast and effective method for estimating clay Li content.Finally,we developed a new method for rapid and nondestructive estimation of soil lithium content.We have obtained some important results from the study.Spectral resolution exerts a significant impact on model performance,and its reduction usually leads to a decline in model performance.For the full band,the models constructed with low-order derivatives were superior to those with high-order derivatives,and the best model was obtained at the 0.4-order derivative(coefficient of determination(R^(2))and relative predictive deviation(RPD)of 0.777 and 2.118,respectively).In the characteristic bands,the lower order is sensitive to the visible-near-infrared range,and the higher order is sensitive to the short-wave infrared range,and the model constructed with the higher-order derivatives outperforms the lower-order derivatives.In this study,the combination of FOD and Random Forest(RF)can significantly improve the model performance,with R^(2),Relative Root Mean Squared Error(RRMSE),and RPD being 0.849,1.526,and 2.574,respectively.Therefore,this research provides a theoretical basis and technical reference for imaging hyperspectral exploration of anomalous areas of clay-type Li resources. 展开更多
关键词 Hyperspectral remote sensing fractional order Derivatives Random Forest LITHIUM Soil pollutant
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Land use type shapes carbon pathways in Tibetan alpine ecosystems:Characterization of ^(13)C abundance in aggregates and density fractions
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作者 Xin Wan Dangjun Wang +7 位作者 Junya Li Shuaiwen Zhang Linyang Li Minghui He Zhiguo Li Hao Jiang Peng Chen Yi Liu 《Journal of Integrative Agriculture》 2026年第2期448-459,共12页
Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In ... Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In this study,the effect of land use type on carbon storage and fractionation was quantified based on organic carbon and its^(13)C abundance at the microscale of soil aggregates and density fractions in Tibetan alpine ecosystems.The sequence of soil aggregate destruction in the land use types of plantation(13.1%)<shrubland(32.7%)<grassland(47.9%)<farmland(61.8%)shows that plantations strengthen the soil structure.Plantation land had a greater contribution of light fraction organic carbon(28.3%)but a lower contribution of mineral-associated organic carbon(40.6%)to the carbon stock compared to farmland(13.5 and 70.3%).Interestingly,plantation land enhanced the aggregational differentiation of organic carbon and^(13)C in each density fraction,whereas no such phenomenon existed in the soil organic carbon.Carbon isotope analyses revealed that carbon transfer in the plantation land occurred from the light fraction in macroaggregates(–24.9‰)to the mineral-associated fraction in microaggregates(–19.9‰).When compared to the other three land use types,the low transferability of carbon in aggregates and density fractions in plantation land provides a stable carbon pool for the Tibetan Plateau.This study shows that plantations can mitigate global climate change by slowing carbon transfer and increasing carbon storage at the microscale of aggregates and density fractions in alpine regions. 展开更多
关键词 land use type soil aggregate density fractions carbon transfer Tibetan Plateau
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Global Optimization Algorithm for Minimizing Linear Fractional Programming
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作者 ZHAO Peng SHEN Pei-ping ZHONG Zhe-wei 《Chinese Quarterly Journal of Mathematics》 2026年第1期50-59,共10页
In this paper,we study a class of Linear Fractional Programming on a nonempty bounded set,called the Problem(LFP),and design a branch and bound algorithm to find the global optimal solution of the problem(LFP).First,w... In this paper,we study a class of Linear Fractional Programming on a nonempty bounded set,called the Problem(LFP),and design a branch and bound algorithm to find the global optimal solution of the problem(LFP).First,we convert the problem(LFP)to the equivalent problem(EP2).Secondly,by applying the linear relaxation technique to the problem(EP2),the linear relaxation programming problem(LRP2Y)was obtained.Then,the overall framework of the algorithm is given,and the convergence and complexity of the algorithm are analyzed.Finally,experimental results are listed to illustrate the effectiveness of the algorithm. 展开更多
关键词 Global optimization Linear fractional Programming Branch and bound algorithm Linear relaxation
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POHOZAEV MINIMIZERS FOR FRACTIONAL CHOQUARD EQUATIONS WITH MASS-SUPERCRITICAL NONLINEARITY
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作者 Liju WU Jiankang XIA 《Acta Mathematica Scientia》 2026年第1期164-188,共25页
We investigate the constrained fractional Choquard equation■where m>0,N>2s with s∈(0,1)being the order of the fractional Laplacian operator and I_(α)forα∈(0,N)denotes the Riesz potential.The parameterμ∈ℝa... We investigate the constrained fractional Choquard equation■where m>0,N>2s with s∈(0,1)being the order of the fractional Laplacian operator and I_(α)forα∈(0,N)denotes the Riesz potential.The parameterμ∈ℝappears as a Lagrange multiplier.By imposing general mass-supercritical conditions on F,we confirm the existence of normalized solutions that characterize the global minimizer on the Pohozaev manifold.Our proof does not depend on the assumption that all weak solutions satisfy the Pohozaev identity,a challenge that remains unsolved for this doubly nonlocal equation. 展开更多
关键词 nonlinear fractional Choquard equation double nonlocality super-critical mass normalized solutions Pohozaev minimizer
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Tribological Properties and Wear Mechanisms of SiCp/6092Al Composites with Different Volume Fractions
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作者 WANG Dongliang DOU Jianming +2 位作者 ZHANG Jilin YI Xiangbin MA Furong 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期323-332,共10页
SiCp-reinforced 6092Al composites with volume fractions of 25%and 60%were prepared using a powder metallurgy method.Their friction and wear characteristics were analyzed using a reciprocating friction and wear testing... SiCp-reinforced 6092Al composites with volume fractions of 25%and 60%were prepared using a powder metallurgy method.Their friction and wear characteristics were analyzed using a reciprocating friction and wear testing machine under loads of 20 to 50 N against YG6 cemented carbide.The experimental results show that the friction coefficients of all samples increase with increasing load.The 25vol%composite exhibits the lowest friction coefficient(0.1669-0.2716),while the 60vol%composite exhibits the highest(0.3237-0.3990),with the 6092 aluminum alloy falling between the two.The wear volume and specific wear rate also increase with load,but the composites with a higher Si C content demonstrate smaller increments,with the 60vol%composite exhibiting superior wear resistance.Under a 30 N load,the wear scars of the 60vol%composite show a significant increase in the contents of elements such as C,Co,W,and O,indicating more severe wear of the counterpart material.Scanning electron microscopy(SEM)reveals wear mechanisms including adhesive wear,two-body sliding and three-body rolling wear of particles,and delamination. 展开更多
关键词 SiCp/6092Al composites wear mechanisms different volume fractions tribological properties
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Developments in the applications of density functional theory to fractional quantum Hall systems
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作者 Yi Yang Yayun Hu Zi-Xiang Hu 《Communications in Theoretical Physics》 2026年第2期220-230,共11页
The fractional quantum Hall effect remains a captivating area in condensed matter physics,characterized by strongly correlated topological order,which manifests as fractionalized excitations and anyonic statistics.Num... The fractional quantum Hall effect remains a captivating area in condensed matter physics,characterized by strongly correlated topological order,which manifests as fractionalized excitations and anyonic statistics.Numerical simulations,such as exact diagonalization,density matrix renormalization groups,matrix product states,and Monte Carlo methods are essential for examining the properties of strongly correlated systems.Recently,density functional theory has been employed in this field within the framework of composite fermion theory.This paper systematically evaluates how density functional theory approaches have addressed fundamental challenges in fractional quantum Hall systems,including ground state and low-energy excitations.Special attention is given to the insights provided by density functional theory regarding composite fermion behavior,edge effects,and the nature of fractional charge and magnetoroton excitations.The discussion critically examines both the advantages and limitations of these approaches,while highlighting the productive interplay between numerical simulations and theoretical models.Future directions are explored,particularly the promising potential of time-dependent density functional theory for modeling non-equilibrium dynamics in quantum Hall systems. 展开更多
关键词 composite fermions fractional quantum Hall effect density functional theory low-lying excitations topological physics
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A Deterministic and Stochastic Fractional-Order Model for Computer Virus Propagation with Caputo-Fabrizio Derivative:Analysis,Numerics,and Dynamics
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作者 Najat Almutairi Mohammed Messaoudi +1 位作者 Faisal Muteb K.Almalki Sayed Saber 《Computer Modeling in Engineering & Sciences》 2026年第3期806-843,共38页
This paper introduces a novel fractional-order model based on the Caputo-Fabrizio(CF)derivative for analyzing computer virus propagation in networked environments.The model partitions the computer population into four... This paper introduces a novel fractional-order model based on the Caputo-Fabrizio(CF)derivative for analyzing computer virus propagation in networked environments.The model partitions the computer population into four compartments:susceptible,latently infected,breaking-out,and antivirus-capable systems.By employing the CF derivative—which uses a nonsingular exponential kernel—the framework effectively captures memory-dependent and nonlocal characteristics intrinsic to cyber systems,aspects inadequately represented by traditional integer-order models.Under Lipschitz continuity and boundedness assumptions,the existence and uniqueness of solutions are rigorously established via fixed-point theory.We develop a tailored two-step Adams-Bashforth numerical scheme for the CF framework and prove its second-order accuracy.Extensive numerical simulations across various fractional orders reveal that memory effects significantly influence virus transmission and control dynamics;smaller fractional orders produce more pronounced memory effects,delaying both infection spread and antivirus activation.Further theoretical analysis,including Hyers-Ulam stability and sensitivity assessments,reinforces the model’s robustness and identifies key parameters governing virus dynamics.The study also extends the framework to incorporate stochastic effects through a stochastic CF formulation.These results underscore fractional-order modeling as a powerful analytical tool for developing robust and effective cybersecurity strategies. 展开更多
关键词 Caputo-Fabrizio derivative fractional-order computer virus model stochastic fractional dynamics Adams-Bashforth scheme Hyers-Ulam stability sensitivity analysis cyber-epidemiology memory effects nonsingular kernel
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The Immunomodulatory,Anti-Tumor,and Metabolic Regulatory Effects of Fraction D of Polysaccharide from Grifola frondosa:Clinical Experiments and Mechanistic Insights
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作者 Nurfarih Hanna Mohd Zarif Fikri Bin Mohd +1 位作者 Muhammad Nabil Fikri Bin Mohd Nurfarazuna Binti Mohd Fadrol 《Proceedings of Anticancer Research》 2026年第1期84-93,共10页
Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical eff... Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical effects and mechanisms in immune enhancement,adjunctive anti-tumor activity,and regulation of glucose/lipid metabolism.Three clinical trials were conducted.In an immune study,120 healthy volunteers(CD4+T cell count 500–1000 cells/μL)received 150 mg/day GFP-D for 8 weeks,resulting in significant increases in CD4+T cells(from 632±95 to 812±108 cells/μL,28.5%increase,within the physiological activation range),CD4+/CD8+ratio,NK cell activity,IL-2,and IFN-γ(all P<0.001 vs.placebo).An anti-tumor study with 80 advanced cancer patients(stratified by age,tumor stage,and histotype)showed that adding 1000 mg/day GFP-D to chemotherapy improved objective response rate(52.5%vs.30.0%,P=0.036,95%CI:1.02–3.87),one-year progression-free survival(55.8%vs.33.3%,P=0.022),and preserved immune parameters versus chemotherapy alone.A metabolic study in 90 type 2 diabetes patients found that 400 mg/day GFP-D for 12 weeks significantly lowered fasting glucose,HbA1c,total cholesterol,triglycerides,and LDL-C,while raising HDL-C(from 1.0±0.2 to 1.2±0.2 mmol/L,20%increase,supported by increased AMPK phosphorylation).Mechanistically,immune enhancement involves macrophage/dendritic cell activation via Dectin-1/TLR4 receptors(confirmed by increased receptor expression and downstream signaling molecules),promoting cytokine-driven T/NK cell responses.Anti-tumor effects stem from immunomodulation,direct induction of cancer cell apoptosis(via mitochondrial/caspase pathways,verified by increased Bax/Bcl-2 ratio and caspase-3 activation),and angiogenesis inhibition by downregulating VEGF.Metabolic benefits are linked to AMPK pathway activation in liver/muscle(confirmed by increased p-AMPK/AMPK ratio),enhancing glucose uptake and inhibiting gluconeogenesis/lipogenesis,alongside modulation of gut microbiota(increased Bifidobacterium and Lactobacillus abundance).All trials reported no severe adverse events related to GFP-D;liver/kidney function parameters(ALT,AST,creatinine,urea nitrogen)remained within normal ranges throughout the intervention.Collectively,GFP-D emerges as a multi-functional bioactive agent with substantial therapeutic potential. 展开更多
关键词 Grifola frondosa Maitake polysaccharide fraction D Immune modulation Adjunctive cancer therapy Glycemic control Lipid metabolism Clinical trial Mechanism of action
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基于VOF-DPM的不同供油压力下扩口式离心喷嘴雾化特性研究
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作者 霍尧 王博涵 《机械管理开发》 2026年第1期9-15,共7页
为揭示供油压力对扩口式离心喷嘴雾化特性的影响规律与内在机理,采用VOF-DPM耦合模型,对喷嘴在0.2~2.0 MPa不同供油压力下的内部流场、出口液膜厚度、雾化锥角及索太尔平均直径(SMD)进行了系统性的数值模拟研究。结果表明:喷嘴内部空气... 为揭示供油压力对扩口式离心喷嘴雾化特性的影响规律与内在机理,采用VOF-DPM耦合模型,对喷嘴在0.2~2.0 MPa不同供油压力下的内部流场、出口液膜厚度、雾化锥角及索太尔平均直径(SMD)进行了系统性的数值模拟研究。结果表明:喷嘴内部空气芯的稳定性是决定雾化形态的关键;供油压力的升高同时增强了燃油的轴向动量与内部离心效应。更强的离心作用使得出口液膜厚度随压力升高而单调减小,从142μm降至114μm,然而由于燃油轴向动量的增幅更为显著,导致喷雾机理从离心主导向轴向主导转变。受此影响,雾化锥角随压力升高而单调减小,从约65°降至55°。更薄的液膜有利于破碎,因此SMD随压力升高而减小,雾化质量得到改善。研究揭示了供油压力对喷嘴雾化特性的调控机制,为喷嘴设计优化与燃烧系统调控提供了理论依据。 展开更多
关键词 扩口式离心喷嘴 vof-DPM模型 雾化特性 供油压力 索太尔平均直径 空气芯
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A_(α)-Spectral Conditions for(a,b,k)-Factor-Critical Graphs and Fractional ID-[a,b]-Factor-Critical Covered Graphs
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作者 Yonglei CHEN Fei WEN 《Journal of Mathematical Research with Applications》 2026年第1期1-12,共12页
In this paper,we first give a sufficient condition for a graph being fractional ID-[a,b]-factor-critical covered in terms of its independence number and minimum degree,which partially answers the problem posed by Sizh... In this paper,we first give a sufficient condition for a graph being fractional ID-[a,b]-factor-critical covered in terms of its independence number and minimum degree,which partially answers the problem posed by Sizhong Zhou,Hongxia Liu and Yang Xu(2022).Then,an A_(α)-spectral condition is given to ensure that G is a fractional ID-[a,b]-factor-critical covered graph and an(a,b,k)-factor-critical graph,respectively.In fact,(a,b,k)-factor-critical graph is a graph which has an[a,b]-factor for k=0.Thus,these above results extend the results of Jia Wei and Shenggui Zhang(2023)and Ao Fan,Ruifang Liu and Guoyan Ao(2023)in some sense. 展开更多
关键词 A_(α)-spectral radius (a b k)-factor fractional(g f)-factor ID-factor-critical graph independence number
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基于DES模型及VOF方法的泄洪消能结构水流脉动特性分析 被引量:1
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作者 侯春尧 张洪毅 +5 位作者 胡长浩 刘璐瑶 刘康 谢辉 李永龙 王皓冉 《科学技术与工程》 北大核心 2025年第18期7770-7777,共8页
强烈的水流脉动是造成消力池等水工结构损伤的重要原因之一,因此明晰水工结构中的水流脉动特性对保障工程安全运行至关重要。基于DES模型及VOF方法建立了亭子口水电站消力池水工模型的精细数值模型,模拟结果与实验结果一致性较好。基于... 强烈的水流脉动是造成消力池等水工结构损伤的重要原因之一,因此明晰水工结构中的水流脉动特性对保障工程安全运行至关重要。基于DES模型及VOF方法建立了亭子口水电站消力池水工模型的精细数值模型,模拟结果与实验结果一致性较好。基于数值模拟结果分析了消力池中压力波动、脉动流速、涡量、以及紊动能的分布变化情况。结果表明消力池中压力波动沿水流方向表现出双峰分布特点,且在水流冲击区脉动量占比超过10%;展向和流向脉动流速在消力池中占主导地位,垂向脉动较弱,在水舌碰撞区域底板中心线处的展向脉动流速迅速减小;底板中心线和表孔中心线上流向和垂向的涡量具有小时均值、大脉动值的特点,跌坎引起的横轴旋涡对展向涡量分布有较大影响。紊动能能谱分析的结果显示消力池中水流脉动主要由大量1Hz以下的低频脉动组成,表明消力池中的紊流波动主要由大尺度和低频的涡流控制。研究结果有助于加深对消力池等泄洪消能结构水流特性的认知,为其设计及安全评估提供了一定参考。 展开更多
关键词 消力池 数值模拟 脉动特性 DES模型 vof方法
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基于VOF模型的真空引水罐内流动特性 被引量:1
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作者 王欢 赵睿杰 +2 位作者 李红 杨帆 潘绪伟 《排灌机械工程学报》 北大核心 2025年第1期74-79,共6页
为解决真空引水罐出口气体流出问题,探究罐内气液两相流动机理,基于RNG k-ε湍流模型和VOF模型对真空引水罐进行计算,对不同初始状态下真空引水罐内的气液两相交界面形态、出口管气体流出量以及出口管内流动状态进行分析,讨论了真空引... 为解决真空引水罐出口气体流出问题,探究罐内气液两相流动机理,基于RNG k-ε湍流模型和VOF模型对真空引水罐进行计算,对不同初始状态下真空引水罐内的气液两相交界面形态、出口管气体流出量以及出口管内流动状态进行分析,讨论了真空引水罐内初始状态对罐内流场的影响,总结了罐内水位对内部流场及出口管的作用关系.结果显示:当初始水位远高于进水管时会大幅优化真空引水罐内流场;与原初始水位相比,罐内气液两相交界面的交互作用减少;气体流出量体积分数峰值从最初的6.916%降至0.106%,平均值从3.442%降至0.027%;出口管流态得到明显改善,顶部低压区域减少.研究结果表明初始水位的变化会影响真空引水罐内流场特性、气体流出量及出口管流态,为深入认识真空引水罐内部流动及真空引水罐的设计提供了数据支撑. 展开更多
关键词 引水罐 流体体积模型 罐内水位 罐内流场 出口流态
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基于VOF方法的码头群桩结构流固耦合动力响应数值模拟 被引量:1
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作者 张其一 孟祥飞 +1 位作者 陈凯 郭东起 《水运工程》 2025年第2期178-183,231,共7页
高桩结构是一种港口海岸码头广泛应用的结构形式,其在波浪作用下的结构动力响应是保证码头稳定运行的关键因素。使用ABAQUS软件建立码头三维模型、STAR-CCM+软件建立波浪水槽,采用k-ε湍流模型和流体体积(VOF)运动界面追踪方法模拟波浪... 高桩结构是一种港口海岸码头广泛应用的结构形式,其在波浪作用下的结构动力响应是保证码头稳定运行的关键因素。使用ABAQUS软件建立码头三维模型、STAR-CCM+软件建立波浪水槽,采用k-ε湍流模型和流体体积(VOF)运动界面追踪方法模拟波浪,实现码头群桩结构和波浪之间双向耦合的模拟。由于桩距与桩直径的比值大于4,不需要考虑桩间相互影响,对比模型试验误差低于5%精度可以满足要求。结果表明,码头群桩在波高为0.3、0.4、0.5 m下的最大受力和位移均能满足规范要求,桩顶处位移最大为0.66 mm;最大应力产生在群桩前排桩底,为152.4 kPa,桩底区域混凝土易发生失稳破坏,实际工程中应格外关注。 展开更多
关键词 群桩结构 vof方法 双向耦合 结构动力响应
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