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Fluorescent coordination polymers based on anthracene-and pyrene-derivative ligands
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作者 XI Jiming TENG Yukang +1 位作者 ZHANG Rui LU Zhenzhong 《无机化学学报》 北大核心 2025年第5期847-854,共8页
We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),campho... We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),camphoric acid(H_(2)cpa)].In[Cd(dip)(cda)]·4H_(2)O}_(n)(1),the Cd^(2+)ions,acting as tetrahedral nodes,are linked by dipand cda^(2-)ligands with four Cd^(2+)ions into five-fold interpenetrating network array of topology of dia.In{[Cd(dip)(cpa)]·4H_(2)O}_(n)(2),the Cd^(2+)ions,acting as a 4-connector,are linked by cpa^(2-)and dip ligands into a 3D framework ofcds topology.In{[Ni(dia)_(2)Cl_(2)]·DMF}_(n)(3),the Ni^(2+)ion is linked by four dia ligands into a layer structure,and 1Dchannels of a cross-section of 1.35 nm×0.96 nm are formed.In{[Cd(dia)_(2)(H_(2)O)_(2)](NO_(3))_(2)·2DMSO}n(4),the dia ligandsconnected Cd^(2+)ions into a 2D layer,and 1D channels are formed between adjacent layers with a cross-section of0.87 nm×0.43 nm.In[Zn(dip)Cl_(2)]_(n)(5),the Zn^(2+)ion is linked by dip ligands into an infinite 1D chain.The infrared,thermal gravimetric,and fluorescent emission data were collected and analyzed for these coordination polymers.CCDC:2356055,1;2440075,2;2356057,3;2356057,4;2356059,5. 展开更多
关键词 coordination polymer anthracene derivatives pyrene derivatives FLUORESCENCE
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4-Dimethylamino-pyridine(DMAP)-Promoted[5+1]Annulation of Isoquinolinium Zwitterions withα-Bromophenones:An Efficient Approach to Hydrogenated 1,4-Thiazino[2,3-a]isoquinoline Tricyclic Derivatives
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作者 Cai Yanan Meng Xiangtai 《有机化学》 北大核心 2025年第9期3429-3440,共12页
An efficient strategy for construction of tricyclic thiazino[3,4-a]isoquinolines has been achieved via 4-dimethylamino-pyridine(DMAP)promoted[5+1]annulation of simple and readily available isoquinoline 1,4-zwitterion ... An efficient strategy for construction of tricyclic thiazino[3,4-a]isoquinolines has been achieved via 4-dimethylamino-pyridine(DMAP)promoted[5+1]annulation of simple and readily available isoquinoline 1,4-zwitterion withα-bromoketone.This protocol showed good substrate compatibility as an array of structurally and electronically diverse thiazino[3,4-a]isoquinolines prepared efficiently in moderate to good yields.It is particularly emphasized that although this reaction exhibits moderate stereoselectivity,the two diastereomers can be separated by column chromatography,providing an important molecular diversity foundation for the screening and structural optimization of subsequent drug lead compounds,as well as a simple and efficient method for constructing complex nitrogen-containing and sulfur-containing heterocyclic compounds.It has potential application value in the fields of medicinal chemistry and organic synthesis. 展开更多
关键词 [5+1]annulation isoquinoline derivative 1 4-thiazine derivative
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Co-regulation effect of solvation and interface of pyridine derivative enabling highly reversible zinc anode 被引量:1
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作者 Binrui Xu Guangbin Wang +3 位作者 Yong Liu Quanan Li Fengzhang Ren Jianmin Ma 《Journal of Materials Science & Technology》 2025年第1期1-9,共9页
The poor reversibility and stability of Zn anodes greatly restrict the practical application of aqueous Zn-ion batteries(AZIBs),resulting from the uncontrollable dendrite growth and H_(2)O-induced side reactions durin... The poor reversibility and stability of Zn anodes greatly restrict the practical application of aqueous Zn-ion batteries(AZIBs),resulting from the uncontrollable dendrite growth and H_(2)O-induced side reactions during cycling.Electrolyte additive modification is considered one of the most effective and simplest methods for solving the aforementioned problems.Herein,the pyridine derivatives(PD)including 2,4-dihydroxypyridine(2,4-DHP),2,3-dihydroxypyridine(2,3-DHP),and 2-hydroxypyrdine(2-DHP),were em-ployed as novel electrolyte additives in ZnSO_(4)electrolyte.Both density functional theory calculation and experimental findings demonstrated that the incorporation of PD additives into the electrolyte effectively modulates the solvation structure of hydrated Zn ions,thereby suppressing side reactions in AZIBs.Ad-ditionally,the adsorption of PD molecules on the zinc anode surface contributed to uniform Zn deposi-tion and dendrite growth inhibition.Consequently,a 2,4-DHP-modified Zn/Zn symmetrical cell achieved an extremely long cyclic stability up to 5650 h at 1 mA cm^(-2).Furthermore,the Zn/NH_(4)V_(4)O_(10)full cell with 2,4-DHP-containing electrolyte exhibited an outstanding initial capacity of 204 mAh g^(-1),with a no-table capacity retention of 79%after 1000 cycles at 5 A g^(-1).Hence,this study expands the selection of electrolyte additives for AZIBs,and the working mechanism of PD additives provides new insights for electrolyte modification enabling highly reversible zinc anode. 展开更多
关键词 Zn anode Pyridine derivative Electrolyte additive Solvation regulation Interface modification
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Profiles,exposure assessment and expanded screening of PAHs and their derivatives in one petroleum refinery facility of China 被引量:1
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作者 Ning Wang Fengjiao Jiang +1 位作者 Lin Xu Yaqi Cai 《Journal of Environmental Sciences》 2025年第1期550-560,共11页
This study investigated environmental distribution and human exposure of polycyclic aromatic hydrocarbons(PAHs)and their derivatives in one Chinese petroleum refinery facility.It was found that,following with high con... This study investigated environmental distribution and human exposure of polycyclic aromatic hydrocarbons(PAHs)and their derivatives in one Chinese petroleum refinery facility.It was found that,following with high concentrations of 16 EPA PAHs(∑Parent-PAHs)in smelting subarea of studied petroleum refinery facility,total derivatives of PAHs[named as XPAHs,including nitro PAHs(NPAHs),chlorinated PAHs(Cl-PAHs),and brominated PAHs(Br-PAHs)]in gas(mean=1.57×10^(4)ng/m^(3)),total suspended particulate(TSP)(mean=4.33×10^(3) ng/m^(3))and soil(mean=4.37×10^(3) ng/g)in this subarea had 1.76-6.19 times higher levels than those from other subareas of this facility,surrounding residential areas and reference areas,indicating that petroleum refining processes would lead apparent derivation of PAHs.Especially,compared with those in residential and reference areas,gas samples in the petrochemical areas had higher∑NPAH/∑PAHs(mean=2.18),but lower∑Cl-PAH/∑PAHs(mean=1.43×10^(-1))and∑Br-PAH/∑PAHs ratios(mean=7.49×10^(-2)),indicating the richer nitrification of PAHs than chlorination during petrochemical process.The occupational exposure to PAHs and XPAHs in this petroleum refinery facility were 24-343 times higher than non-occupational exposure,and the ILCR(1.04×10^(-4))for petrochemical workers was considered to be potential high risk.Furthermore,one expanded high-resolution screening through GC Orbitrap/MS was performed for soils from petrochemical area,and another 35 PAHs were found,including alkyl-PAHs,phenyl-PAHs and other species,indicat-ing that profiles and risks of PAHs analogs in petrochemical areas deserve further expanded investigation. 展开更多
关键词 Polycyclic aromatic hydrocarbons(PAHs) derivativeS Petroleum refinery Human exposure Non-targeted screening
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Curvularin derivatives from hydrothermal vent sediment fungus Penicillium sp.HL-50 guided by molecular networking and their antiinflammatory activity 被引量:1
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作者 Chunxue Yu Zixuan Xia +6 位作者 Zhipeng Xu Xiyang Tang Wenjuan Ding Jihua Wei Danmei Tian Bin Wu Jinshan Tang 《Chinese Journal of Natural Medicines》 2025年第1期119-128,共10页
Guided by molecular networking,nine novel curvularin derivatives(1-9)and 16 known analogs(10-25)were isolated from the hydrothermal vent sediment fungus Penicillium sp.HL-50.Notably,compounds 5-7 represented a hybrid ... Guided by molecular networking,nine novel curvularin derivatives(1-9)and 16 known analogs(10-25)were isolated from the hydrothermal vent sediment fungus Penicillium sp.HL-50.Notably,compounds 5-7 represented a hybrid of curvularin and purine.The structures and absolute configurations of compounds 1-9 were elucidated via nuclear magnetic resonance(NMR)spectroscopy,X-ray diffraction,electronic circular dichroism(ECD)calculations,^(13)C NMR calculation,modified Mosher's method,and chemical derivatization.Investigation of anti-inflammatory activities revealed that compounds 7-9,11,12,14,15,and 18 exhibited significant suppressive effects against lipopolysaccharide(LPS)-induced nitric oxide(NO)production in murine macrophage RAW264.7 cells,with IC_(50)values ranging from 0.44 to 4.40μmol·L^(-1).Furthermore,these bioactive compounds were found to suppress the expression of inflammation-related proteins,including inducible NO synthase(i NOS),cyclooxygenase-2(COX-2),NLR family pyrin domain-containing protein 3(NLRP3),and nuclear factor kappa-B(NF-κB).Additional studies demonstrated that the novel compound 7 possessed potent antiinflammatory activity by inhibiting the transcription of inflammation-related genes,downregulating the expression of inflammation-related proteins,and inhibiting the release of inflammatory cytokines,indicating its potential application in the treatment of inflammatory diseases. 展开更多
关键词 Penicillium sp.HL-50 Curvularin derivatives Molecular networking Anti-inflammatory activity
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Design,Synthesis,and Activity Assessment of Fudosteine Derivatives for Chronic Respiratory Disorders
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作者 Sun Maoru Gui Tengyao +2 位作者 Chen Congdi Yang Hongjun Li Xuefeng 《有机化学》 北大核心 2025年第7期2566-2576,共11页
Chronic obstructive pulmonary disease(COPD)has garnered increased attention as a result of its persistent symptoms,which undermine patientsʼquality of life.Fudosteine has substantial advantages in the treatment of COP... Chronic obstructive pulmonary disease(COPD)has garnered increased attention as a result of its persistent symptoms,which undermine patientsʼquality of life.Fudosteine has substantial advantages in the treatment of COPD due to its high efficacy and low adverse effects.In this study,Fudosteine sulfonamide derivatives Series I and amine derivatives Series II were designed and synthesized,and their biological activities were evaluated.The results showed that compound 6f had outstanding anti-inflammatory action with an IC_(50) of 1.08 mmol/L,and a higher antioxidant capacity than the lead molecule.At the same time,molecular docking investigations have revealed that compound 6f establishes hydrogen bonds and hydrophobic contacts with the MUC5AC protein.Furthermore,derivative 1f inhibited PDE4A1 enzyme activity five times more than Fudosteine.2,2-Diphenyl-1-picrylhydrazyl(DPPH)free radical scavenging tests demonstrated that all examined substances had higher antioxidant activity than Fudosteine.This study established a solid foundation for further research into COPD drug therapy. 展开更多
关键词 FUDOSTEINE chronic obstructive pulmonary disease(COPD) amine derivatives MUC5AC
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Advances in selective hydrogenation ofα,β‑unsaturated aldehydes/ketones catalyzed by metal‑organic frameworks and their derivatives:A review
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作者 YANG Jiaxuan DENG Chenfa +7 位作者 LIU Jingyang XU Chenzexi CHEN Hongxin ZHU Yahui LI Ying WANG Shuhua ZHOU Rongping CHEN Chao 《无机化学学报》 北大核心 2025年第10期1973-2010,共38页
The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively red... The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively reduce C=C or C=O bonds while preserving other functional groups within the molecule.This approach serves as a critical strategy for the directional synthesis of high-value molecules.However,achieving such selectivity remains challenging due to the thermodynamic equilibrium and kinetic competition between C=O and C=C bonds inα,β-unsaturated systems.Consequently,constructing precisely targeted catalytic systems is essential to overcome these limitations,offering both fundamental scientific significance and industrial application potential.Metal-organic frameworks(MOFs)and their derivatives have emerged as innovative platforms for designing such systems,owing to their programmable topology,tunable pore microenvironments,spatially controllable active sites,and modifiable electronic structures.This review systematically summarizes the research progress of MOF-based catalysts for selec-tive hydrogenation ofα,β-unsaturated aldehydes/ketones in the last decade,with emphasis on the design strategy,conformational relationship,and catalytic mechanism,aiming to provide new ideas for the design of targeted catalyt-ic systems for the selective hydrogenation ofα,β-unsaturated aldehydes/ketones. 展开更多
关键词 α β-unsaturated aldehydes/ketones metal-organic frameworks derivativeS selective hydrogenation catalytic mechanism hydrogenation path
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Novel Bipolar Hosts for Solution-processable Green Phosphorescent OLEDs Based on Tetrasubstituted Carbazole Derivatives
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作者 HUANG Hong ZHANG Youming +2 位作者 HUA Tao LI Nengquan XIE Guohua 《发光学报》 北大核心 2025年第11期1971-1979,共9页
Two tetrasubstituted carbazole derivatives TBICz and TOXDCz have been designed and synthesized,which possess the twist skeletons and exhibit excellent thermal and morphological stabilities.Utilizing these novel compou... Two tetrasubstituted carbazole derivatives TBICz and TOXDCz have been designed and synthesized,which possess the twist skeletons and exhibit excellent thermal and morphological stabilities.Utilizing these novel compounds as host material,high efficiency solution-processed green phosphorescent organic light-emitting diodes(PhOLEDs)have been achieved.The high triplet energies of TBICz and TOXDCz ensure efficient energy transfer from the host to the phosphor and triplet exciton confinement on the phosphor.Solution-processable green phospho⁃rescent devices employing Ir(ppy)3 as vip and the two tetrasubstituted carbazole derivatives as hosts exhibit high ef⁃ficiencies.The best EL performance is achieved for the TBICz-based device,with a maximum current efficiency of 27.3 cd/A,a maximum power efficiency of 15.9 lm/W,and a maximum external quantum efficiency of 7.8%,which provides more host material options for solution-processed OLEDs. 展开更多
关键词 tetrasubstituted carbazole derivatives green phosphorescent organic light-emitting diodes solution-pro⁃cessed bipolar host
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DCNN Based Finger Knuckle Print Recognition Using C-ROI Morphological Segmentation and Derivative Line Extraction
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作者 Sathiya L Palanisamy V 《China Communications》 2025年第11期144-160,共17页
One of the evolving hand biometric features considered so far is finger knuckle printing,because of its ability towards unique identification of individuals.Despite many attempts have been made in this area of researc... One of the evolving hand biometric features considered so far is finger knuckle printing,because of its ability towards unique identification of individuals.Despite many attempts have been made in this area of research,the accuracy of the recognition model remains a major issue.To overcome this problem,a novel biometric-based method,named fingerknuckle-print(FKP),has been developed for individual verification.The proposed system carries key steps such as preprocessing,segmentation,feature extraction and classification.Initially input FKP image is fed into the preprocessing stage where colour images are converted to gray scale image for augmenting the system performance.Afterwards,segmentation process is carried out with the help of CROI(Circular Region of Interest)and Morphological operation.Then,feature extraction stage is carried out using Gabor-Derivative line approach for extracting intrinsic features.Finally,DCNN(Deep Convolutional Neural Network)is trained for the processed knuckle images to recognize imposter and genuine individuals.Extensive experiments on standard FKP database demonstrates that the proposed method attains considerable improvement compared with state-of-the-art methods.The overall accuracy attained for the proposed methodology is 95.6%which is achieved better than the existing techniques. 展开更多
关键词 ACCURACY deep convolutional neural network derivative line method gabor filter morphological segmentation sensitivity
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On Nonlinear Analysis for Multi-term Delay Fractional Differential Equations Under Hilfer Derivative
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作者 Dildar Ahmad Amjad Ali +2 位作者 Kamal Shah Bahaaeldin Abdalla Thabet Abdeljawad 《Communications on Applied Mathematics and Computation》 2025年第4期1516-1539,共24页
In this manuscript,a class of multi-term delay fractional differential equations(FDEs)under the Hilfer derivative is considered.Some newly updated results are established under boundary conditions.For the required res... In this manuscript,a class of multi-term delay fractional differential equations(FDEs)under the Hilfer derivative is considered.Some newly updated results are established under boundary conditions.For the required results,we utilize the fixed point theory and tools of the nonlinear functional analysis.Further keeping in mind the importance of stability results,we develop some adequate results about the said aspect.The Hyers-Ulam(H-U)-type concept is used to derive the required stability for the solution of the considered problem.Finally,by appropriate test problems,we justify our findings. 展开更多
关键词 Hilfer derivative Multi-term Existence results STABILITY
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Prediction of Frozen Soil Deformation Characteristics Using Fractional Derivative Creep Model
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作者 Zhiheng Tian 《Journal of Architectural Research and Development》 2025年第5期50-56,共7页
To investigate the temperature susceptibility and nonlinear memory effects of artificially frozen soil creep behavior,this study conducted uniaxial step-loading creep tests under controlled temperatures ranging from-1... To investigate the temperature susceptibility and nonlinear memory effects of artificially frozen soil creep behavior,this study conducted uniaxial step-loading creep tests under controlled temperatures ranging from-10℃to-20℃.The transient creep characteristics and steady-state creep rates of artificially frozen soils were systematically examined with respect to variations in temperature and stress.Experimental results demonstrate that decreasing temperatures lead to a decaying trend in the steady-state creep rate of silty frozen soil,confirming that low-temperature environments significantly inhibit plastic flow while enhancing material stiffness.Based on fractional calculus theory,a fractional derivative creep model was established.By incorporating temperature dependencies,the model was further improved to account for both stress and temperature effects.The model predictions align closely with experimental data,achieving over 91%agreement(standard deviation±1.8%),and effectively capture the stress-strain behavior of artificially frozen soil under varying thermal conditions.This research provides a reliable theoretical foundation for studying deformation characteristics in cold-regions engineering. 展开更多
关键词 Frozen soil Fractional derivative Creep deformation Constitutive model
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Uncovering Hidden Spin of Scalar Fields with Higher-Order Derivative Lagrangian:On the Wave Spin in Drifted and Dissipative Fields
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作者 Shuo Xin Mengxiang Xie Jie Ren 《Chinese Physics Letters》 2025年第6期70-77,共8页
Scalar fields should have no spin angular momentum according to conventional textbook understandings inclassical field theory.Yet,recent studies demonstrate the undoubted existence of wave spin endowed by acousticand ... Scalar fields should have no spin angular momentum according to conventional textbook understandings inclassical field theory.Yet,recent studies demonstrate the undoubted existence of wave spin endowed by acousticand elastic longitudinal waves,which are of irrotational curl-free nature without vorticity and can be describedby scalar fields.Moreover,the conventional theory cannot even answer the question of whether wave spin existsin dissipative fields,given the ubiquitous dissipation in reality.Here,to resolve the seeming paradox and answerthe challenging question,we uncover the origin of wave spin in scalar fields beyond traditional formalism byclarifying that the presence of higher-order derivatives in scalar field Lagrangians can give rise to non-vanishingwave spin.For“spinless”scalar fields of only first-order derivatives,we can make the hidden wave spin emergeby revealing a latent field that leads to the original field through a time derivative,thus giving higher-order termsin Lagrangian.Based on the standard Noether theorem approach,we exemplify the wave spin for unconventionaldrifted acoustic fields,and even for dissipative media,in scalar fields with higher-order derivative Lagrangian.The results would prompt people to build more comprehensive and fundamental understandings of structuralwave spin in classical fields. 展开更多
关键词 higher order derivative Lagrangian hidden spin acousticand elastic longitudinal waveswhich acoustic waves wave spin spin angular momentum scalar fields
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Analysis of a Laplace Spectral Method for Time-Fractional Advection-Diffusion Equations Incorporating the Atangana-Baleanu Derivative
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作者 Kamran Farman Ali Shah +3 位作者 Kallekh Afef J.F.Gómez-Aguilar Salma Aljawi Ioan-Lucian Popa 《Computer Modeling in Engineering & Sciences》 2025年第6期3433-3462,共30页
In this article,we develop the Laplace transform(LT)based Chebyshev spectral collocation method(CSCM)to approximate the time fractional advection-diffusion equation,incorporating the Atangana-Baleanu Caputo(ABC)deriva... In this article,we develop the Laplace transform(LT)based Chebyshev spectral collocation method(CSCM)to approximate the time fractional advection-diffusion equation,incorporating the Atangana-Baleanu Caputo(ABC)derivative.The advection-diffusion equation,which governs the transport of mass,heat,or energy through combined advection and diffusion processes,is central to modeling physical systems with nonlocal behavior.Our numerical scheme employs the LT to transform the time-dependent time-fractional PDEs into a time-independent PDE in LT domain,eliminating the need for classical time-stepping methods that often suffer from stability constraints.For spatial discretization,we employ the CSCM,where the solution is approximated using Lagrange interpolation polynomial based on the Chebyshev collocation nodes,achieving exponential convergence that outperforms the algebraic convergence rates of finite difference and finite element methods.Finally,the solution is reverted to the time domain using contour integration technique.We also establish the existence and uniqueness of the solution for the proposed problem.The performance,efficiency,and accuracy of the proposed method are validated through various fractional advection-diffusion problems.The computed results demonstrate that the proposed method has less computational cost and is highly accurate. 展开更多
关键词 Laplace transform spectral method existence theory fractional derivative with non-singular kernel contour integration methods
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Approximate Controllability of Neutral Partial Differential System with Hilfer Fractional Derivative and not Instantaneous Impulses Effects
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作者 Bo ZHU Baoyan HAN 《Journal of Mathematical Research with Applications》 2025年第5期637-648,共12页
In this article,we study the approximate controllability of neutral partial differential equations with Hilfer fractional derivative and not instantaneous impulses effects.By using the Sadovskii's fixed point theo... In this article,we study the approximate controllability of neutral partial differential equations with Hilfer fractional derivative and not instantaneous impulses effects.By using the Sadovskii's fixed point theorem,fractional calculus and resolvent operator functions,we prove the approximate controllability of the considered system. 展开更多
关键词 approximate controllability Hilfer fractional derivative not instantaneous impulses resolvent operator functions
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Quantum Geometric Tensor for Mixed States Based on the Covariant Derivative
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作者 Qianyi Wang Ben Wang +1 位作者 Jun Wang Lijian Zhang 《Chinese Physics Letters》 2025年第7期171-181,共11页
The quantum geometric tensor(QGT)is a fundamental quantity for characterizing the geometric properties of quantum states and plays an essential role in elucidating various physical phenomena.The traditional QGT,defned... The quantum geometric tensor(QGT)is a fundamental quantity for characterizing the geometric properties of quantum states and plays an essential role in elucidating various physical phenomena.The traditional QGT,defned only for pure states,has limited applicability in realistic scenarios where mixed states are common.To address this limitation,we generalize the defnition of the QGT to mixed states using the purifcation bundle and the covariant derivative.Notably,our proposed defnition reduces to the traditional QGT when mixed states approach pure states.In our framework,the real and imaginary parts of this generalized QGT correspond to the Bures metric and the mean gauge curvature,respectively,endowing it with a broad range of potential applications.Additionally,using our proposed mixed-state QGT,we derive the geodesic equation applicable to mixed states.This work establishes a unifed framework for the geometric analysis of both pure and mixed states,thereby deepening our understanding of the geometric properties of quantum states. 展开更多
关键词 characterizing geometric properties quantum states purifcation bundle elucidating various physical phenomenathe covariant derivative Bures metric quantum geometric tensor qgt quantum geometric tensor mixed states
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Mathematical Model of the Monkeypox Virus Disease via ABC Fractional Order Derivative
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作者 Rajagopalan Ramaswamy Gunaseelan Mani +1 位作者 Deepak Kumar Ozgur Ege 《Computer Modeling in Engineering & Sciences》 2025年第5期1843-1894,共52页
The Department of Economic and Social Affairs of the United Nations has released seventeen goals for sustainable development and SDG No.3 is“Good Health and Well-being”,which mainly emphasizes the strategies to be a... The Department of Economic and Social Affairs of the United Nations has released seventeen goals for sustainable development and SDG No.3 is“Good Health and Well-being”,which mainly emphasizes the strategies to be adopted for maintaining a healthy life.The Monkeypox Virus disease was first reported in 1970.Since then,various health initiatives have been taken,including by the WHO.In the present work,we attempt a fractional model of Monkeypox virus disease,which we feel is crucial for a better understanding of this disease.We use the recently introduced ABC fractional derivative to closely examine the Monkeypox virus disease model.The evaluation of this model determines the existence of two equilibrium states.These two stable points exist within the model and include a disease-free equilibrium and endemic equilibrium.The disease-free equilibrium has undergone proof to demonstrate its stability properties.The system remains stable locally and globally whenever the effective reproduction number remains below one.The effective reproduction number becoming greater than unity makes the endemic equilibrium more stable both globally and locally than unity.To comprehensively study the model’s solutions,we employ the Picard-Lindelof approach to investigate their existence and uniqueness.We investigate the Ulam-Hyers and UlamHyers Rassias stability of the fractional order nonlinear framework for the Monkeypox virus disease model.Furthermore,the approximate solutions of the ABC fractional order Monkeypox virus disease model are obtained with the help of a numerical technique combining the Lagrange polynomial interpolation and fundamental theorem of fractional calculus with the ABC fractional derivative. 展开更多
关键词 ABC fractional derivative monkeypox virus disease existence and uniqueness fixed point theory
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Some regularity properties of scattering data for the derivative nonlinear Schrödinger equation
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作者 Weifang Weng Zhenya Yan 《Communications in Theoretical Physics》 2025年第5期1-20,共20页
In this paper,we present some properties of scattering data for the derivative nonlinear Schrödinger equation in H^(S)(R)(s≥1/2)starting from the Lax pair.We show that the reciprocal of the transmission coeffici... In this paper,we present some properties of scattering data for the derivative nonlinear Schrödinger equation in H^(S)(R)(s≥1/2)starting from the Lax pair.We show that the reciprocal of the transmission coefficient can be expressed as the sum of some iterative integrals,and its logarithm can be written as the sum of some connected iterative integrals.We provide the asymptotic properties of the first few iterative integrals of the reciprocal of the transmission coefficient.Moreover,we provide some regularity properties of the reciprocal of the transmission coefficient related to scattering data in H^(S)(R). 展开更多
关键词 derivative nonlinear Schrödinger equation modified Zakharov-Shabat spectral problem scattering data inverse scattering transform ASYMPTOTICS
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Simulation-Based Novel Hybrid Proportional Derivative/H-Infinity Controller Design for Improved Trajectory Tracking of a Two-Link Robot Arm
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作者 BANKOLE Adesola Temitope IGBONOBA Ezekiel Endurance Chukwuemeke 《Journal of Shanghai Jiaotong university(Science)》 2025年第6期1179-1187,共9页
A hybrid control strategy integrating proportional derivative(PD)and the H-infinity control methodology is proposed for a serial two-link robotic manipulator with the goal of improving the tracking performance of the ... A hybrid control strategy integrating proportional derivative(PD)and the H-infinity control methodology is proposed for a serial two-link robotic manipulator with the goal of improving the tracking performance of the robot arm.The H-infinity controller has the ability to achieve a high performance and robustness in the presence of disturbances and uncertainties,while the PD controller is effective in stabilizing the manipulator.Simulation results using Matlab and Simulink show that the proposed hybrid controller,which integrates the advantages of both PD and H-infinity controllers,has the lowest rise time for the second link,the lowest settling time for the two links,the lowest peak time for both links,and the fastest decay of the error response.In addition,the hybrid control scheme also has the lowest mean square error value,with a 53.3%improvement over the H-infinity controller and a 91.8%improvement over the PD controller,indicating an improved trajectory tracking performance when compared with pure PD and pure H-infinity controllers,respectively.It was also found that the hybrid controller has the lowest integral absolute error,integral square error,integral time absolute error,and integral time square error for the second link,while the error values for the first link are satisfactory,showing a superior performance of the hybrid controller above the PD and H-infinity controllers,respectively. 展开更多
关键词 robot arm trajectory tracking proportional derivative(PD)control H-infinity control hybrid PD/H-infinity control
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Vibralactone derivatives isolated from co-cultures of the basidiomycetes Stereum hirsutum and Boreostereum vibrans
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作者 Jinjuan Wei Zhe-Xi Li +3 位作者 Gao-Ke Peng Xinyang Li He-Ping Chen Ji-Kai Liu 《Natural Products and Bioprospecting》 2025年第2期176-185,共10页
The basidiomycetes Stereum hirsutum and Boreostereum vibrans are two fungi of the same genus.In this study,chemical investigation on the co-cultures of the two congeneric fungi led to the isolation of eleven new vibra... The basidiomycetes Stereum hirsutum and Boreostereum vibrans are two fungi of the same genus.In this study,chemical investigation on the co-cultures of the two congeneric fungi led to the isolation of eleven new vibralactone derivatives,hirsutavibrins A-K(1-11).The structures of 1-11 were elucidated by extensive NMR and HRESIMS spectroscopic analysis,and computational methods.Hirsutavibrins A(1)and B(2)showed weak cytotoxicity against the human lung cancer cell line A549.Hirsutavibrin D(4)showed moderate anti-nitric oxide activity in murine monocytic RAW 264.7 macrophages.This work not only expands the members of vibralactone derivatives with variable configurations but also opens a new avenue for fungal co-culturing study between congeneric fungi. 展开更多
关键词 Stereum hirsutum Boreostereum vibrans BASIDIOMYCETES CO-CULTURE Vibralactone derivatives
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Numerical Treatments for a Crossover Cholera Mathematical Model Combining Different Fractional Derivatives Based on Nonsingular and Singular Kernels
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作者 Seham M.AL-Mekhlafi Kamal R.Raslan +2 位作者 Khalid K.Ali Sadam.H.Alssad Nehaya R.Alsenaideh 《Computer Modeling in Engineering & Sciences》 2025年第5期1927-1953,共27页
This study introduces a novel mathematical model to describe the progression of cholera by integrating fractional derivatives with both singular and non-singular kernels alongside stochastic differential equations ove... This study introduces a novel mathematical model to describe the progression of cholera by integrating fractional derivatives with both singular and non-singular kernels alongside stochastic differential equations over four distinct time intervals.The model incorporates three key fractional derivatives:the Caputo-Fabrizio fractional derivative with a non-singular kernel,the Caputo proportional constant fractional derivative with a singular kernel,and the Atangana-Baleanu fractional derivative with a non-singular kernel.We analyze the stability of the core model and apply various numerical methods to approximate the proposed crossover model.To achieve this,the approximation of Caputo proportional constant fractional derivative with Grünwald-Letnikov nonstandard finite difference method is used for the deterministic model with a singular kernel,while the Toufik-Atangana method is employed for models involving a non-singular Mittag-Leffler kernel.Additionally,the integral Caputo-Fabrizio approximation and a two-step Lagrange polynomial are utilized to approximate the model with a non-singular exponential decay kernel.For the stochastic component,the Milstein method is implemented to approximate the stochastic differential equations.The stability and effectiveness of the proposed model and methodologies are validated through numerical simulations and comparisons with real-world cholera data from Yemen.The results confirm the reliability and practical applicability of the model,providing strong theoretical and empirical support for the approach. 展开更多
关键词 Cholera crossover model Caputo proportional constant fractional derivative Caputo-Fabrizio
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