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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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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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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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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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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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Comprehensive review of synthesis strategies and performance enhancement of metal-organic frameworks and their derivatives for photocatalytic applications
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作者 Huihua Luo Lianqing Yu +5 位作者 Chong Liu Nannan Chen Kehui Xue Wendi Liu Haifeng Zhu Yaping Zhang 《Journal of Energy Chemistry》 2025年第4期408-439,共32页
Energy conversion and environmental pollution present significant challenges that necessitate the development of materials with optimal characteristics for effective applications in solar energy-driven photocatalysis.... Energy conversion and environmental pollution present significant challenges that necessitate the development of materials with optimal characteristics for effective applications in solar energy-driven photocatalysis.Metal-organic frameworks(MOFs)serve as excellent platforms for the development of various MOF-derived materials,which have garnered extensive attention due to their unique structural features,high crystallinity,large surface areas,diverse morphologies,adjustable dimensions,tunable textural characteristics,and inherent catalytic activity.However,the sluggish charge kinetics and poor stability of MOFs and MOF-derived photocatalysts restrict their photocatalytic activity,thereby limiting their applications in the field of photocatalysis.Consequently,substantial research efforts have been directed toward maximizing the advantages of these intriguing materials while addressing their shortcomings.This review provides a comprehensive summary and analysis of various synthesis strategies of MOFs and their derivatives.Effective modification strategies to enhance the performance of these novel materials are also summarized.This review systematically explores the current advancements in the application of MOFs and their derivatives for photocatalytic water splitting,photocatalytic CO_(2)reduction,and environmental water pollution treatment.Finally,it discusses the challenges and future prospects of MOFs and MOF-derived materials in photocatalytic applications.Researchers should systematically optimize synthetic strategies and functionalize MOFs and their derivatives to enhance their application in energy conversion and environmental pollution control,thereby underscoring their extensive potential.Future research will increasingly concentrate on the intelligent design and functionalization of MOFs to attain superior catalytic performance and tackle the urgent energy and environmental challenges confronting the world. 展开更多
关键词 Metal-organic frameworks derivativeS Energy convention Environmental pollution
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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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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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Design,synthesis and biological evaluation of buthutin derivatives as cardioprotective agents
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作者 Yuan Liu Fa-Qi Wang +6 位作者 Xin-Hao Hua Shu-Han Yang Li-Ning Wang Yun-Sheng Xu Chen-Yue Shao Xiang-Bo Gou Yu-Ming Liu 《Natural Products and Bioprospecting》 2025年第2期25-38,共14页
Natural products are the important sources in cardiovascular drug development.In this study,twenty-nine buthutin derivatives were designed,synthesized,and evaluated for their NHE-1 inhibition and protective effects on... Natural products are the important sources in cardiovascular drug development.In this study,twenty-nine buthutin derivatives were designed,synthesized,and evaluated for their NHE-1 inhibition and protective effects on cardiomyo-cyte injury.The structure of the newly synthesized compounds had been confirmed by 1H-NMR,13C-NMR,and HR-ESI-MS spectra.Among all target compounds at 1μM,compounds 9d,9f,9k,9m,and 9n,with a protection ratio exceeding 30%,exerted stronger protective effects on H9c2 cardiomyocyte than positive control dexrazoxane and buthutin A.Meanwhile,compounds 9k,9m,and 9o showed the significant NHE-1 inhibitory activities on H9c2 cardiomyocyte,all with a dpHi/min value less than 0.23.What is more,compounds 9k,9m,9o and buthutin A all exhibited the specificity on NHE-1 inhibition.Molecular modelling studies suggested the ability of compounds 9m and 9o to establish interactions with three hydrogen bonds to Asp267 and Glu346 of NHE-1,but also the ability with much lower CDOCKER energies than positive control cariporide and buthutin A.The structure-activity relationship(SAR)studies suggested that the presences of amide group,four-carbon linker,and para hydroxyl benzene ring were advantageous pharmacophores for above two pharmacological actions.This research would open new avenues for developing amide-guanidine-based cardioprotective agents. 展开更多
关键词 Buthus martensii Amide-guanidine derivatives Cardioprotective agents NHE-1
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Synthesis of 5-hydroxymethylfurfural and its oxidation derivatives by immobilized catalysts:An efficient green sustainable technology
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作者 Yao Chen Jun Ge 《Chinese Journal of Catalysis》 2025年第4期5-24,共20页
5-Hydroxymethylfurfural(HMF)and its oxidation derivatives have emerged as a bridge between biomass resources and the future energy industry.These renewable biomass resources can be transformed into a variety of value-... 5-Hydroxymethylfurfural(HMF)and its oxidation derivatives have emerged as a bridge between biomass resources and the future energy industry.These renewable biomass resources can be transformed into a variety of value-added chemicals,thereby addressing the challenges posed by diminishing fossil fuel reserves and environmental concerns.The immobilization of catalysts represents an innovative method for the sustainable and efficient synthesis of HMF and its oxidation derivatives.This method not only enhances the yield and selectivity of the products but also allows for the optimization of the catalytic performance of immobilized catalysts through the strategic design of their supports.In this review,we provide an overview of the recent advancements in the technology of immobilized catalyst and its application in the synthesis of HMF and its oxidation derivatives,with a particular focus on the preparation and catalytic characteristics of these immobilized catalysts.Furthermore,we discuss potential future directions for the development of immobilized catalysts,including the preparation of high-performance immobilized catalysts,the exploration of their growth and catalytic mechanisms,and the economic implications of raw material utilization.This area of research presents both significant promise and considerable challenges. 展开更多
关键词 5-HYDROXYMETHYLFURFURAL Oxidized derivatives IMMOBILIZATION Immobilized catalyst Catalytic property
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Extraction,Utilization,Functional Modification,and Application of Cellulose and Its Derivatives
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作者 Wohua He Fangji Wu Haoqun Hong 《Journal of Renewable Materials》 2025年第9期1707-1763,共57页
Under the background of the current energy crisis and environmental pollution,the development of green and sustainable materials has become particularly urgent.As one of the most abundant natural polymers on earth,cel... Under the background of the current energy crisis and environmental pollution,the development of green and sustainable materials has become particularly urgent.As one of the most abundant natural polymers on earth,cellulose has attracted wide attention due to its green recycling,sustainable development,degradability,and low cost.Therefore,cellulose and its derivatives were used as the starting point for comprehensive analysis.First,the basic structural properties of cellulose were discussed,and then the extraction and utilization methods of cellulose were reviewed,including Sodium Hydroxide based solvent system,N,N-Dimethylacetamide/Lithium Chloride System,N-Methylmorpholine-N-Oxide(NMMO)system,ionic liquids(ILs)system,and deep eutectic solvent(DES)system.Then,the functional modification techniques of cellulose are introduced,including nano-modification,small molecule modification,and macromolecular modification.Finally,the potential applications of cellulose in the fields of reinforcement materials,self-healing materials,radioactive cooling,nanogenerators,and biomedicine were discussed.At the end of this paper,the challenges and future development direction of cellulose materials are prospectively analyzed,aiming at providing guidance and inspiration for the research and application in related fields. 展开更多
关键词 Cellulose and derivatives extraction and utilization functional modification APPLICATIONS
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Catalytic production of high-energy-density spiro polycyclic jet fuel with biomass derivatives
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作者 Wen-Jing Zhang Yan-Cheng Hu +3 位作者 Yan-Hong Tan Jia Li Ning Li Jing-Pei Cao 《Journal of Energy Chemistry》 2025年第2期760-768,I0016,共10页
High-energy-density(HED)fuel(e.g.widely used JP-10 and RJ-4),featuring compact 3D polycyclic structure with high strain,is of critical importance for volume-limited military aircraft,since their high density and combu... High-energy-density(HED)fuel(e.g.widely used JP-10 and RJ-4),featuring compact 3D polycyclic structure with high strain,is of critical importance for volume-limited military aircraft,since their high density and combustion heat can provide more propulsion energy.To reduce the reliance on petroleum source,it is highly desirable to develop renewable alternatives for the production of strained polycyclic HED fuel,but which remains a big challenge because of the inaccessibility caused by the high strain,We herein demonstrate a three-step catalytic route towards highly strained C_(17)and C_(18)spirofuel with biomass feedstocks.The process includes catalytic aldol condensation of renewable cyclohexanone/cyclopentanone with benzaldehyde,catalytic spiro Diels-Alder(D-A)reaction of aldol adduct with isoprene,and catalytic hydrodeoxygenation.The key spiro D-A reaction is enabled by the catalysis of heterogeneous Lewis acidic ionic liquid.The chloroaluminate IL,formed by benign urea and AICl3,exhibits good catalytic performance and reusability for this step.An eventual hydrodeoxygenation(HDO)over Pd/C and H-Y produces strained tricyclic spirofuel with density>0.93 g/mL,combustion heat>41 MJ/L and freezing point<-40℃,which are better than the properties of tactical fuel RJ-4.Therefore,it is anticipated that the as-prepared renewable fuels have the potential to replace traditional petroleum-derived HED fuels. 展开更多
关键词 Biomass derivatives High-energy-density Spiro polycyclic fuel Cycloaddition Lewis acidic ionic liquid
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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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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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Withanolide derivatives from Physalis angulata var.villosa and their cytotoxic activities
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作者 Peng Wang Jue Yang +5 位作者 Yu Zhang Jun jin Meijun Chen Xiaojiang Hao Chunmao Yuan Ping Yi 《Chinese Journal of Natural Medicines》 2025年第6期762-768,共7页
A comprehensive phytochemical investigation of the leaves and twigs of Physalis angulata.var.villosa resulted in the isolation of 23 withanolide derivatives,including one novel 13,20-γ-lactone withanolide derivative(... A comprehensive phytochemical investigation of the leaves and twigs of Physalis angulata.var.villosa resulted in the isolation of 23 withanolide derivatives,including one novel 13,20-γ-lactone withanolide derivative(1)and three new withanolide derivatives(2-4).Architecturally,physalinin A(1)represents the first identified type B withanolide featuring a 13,20-γ-lactone moiety.The molecular structures of all isolates were elucidated using an integrated approach combining nuclear magnetic resonance(NMR)spectroscopy,mass spectrometry(MS),infrared(IR)spectroscopy,and quantum chemical calculations to confirm structural assignments.The antiproliferative activities of all isolated withanolides were evaluated against four human cancer cell lines(HEL,HCT-116,Colo320DM,and MDA-MB-231).Among them,eight derivatives(2,5–8,14,15,and 23)exhibited significant inhibitory effects,with half-maximal inhibitory concentration(IC50)values of 0.18±0.03 to 17.02±0.21μmol·L-1.Structureactivity relationship(SAR)analysis suggested that the presence of an epoxide ring enhances anticancer activity,potentially through increased reactivity or specific interactions with molecular targets involved in cancer progression.These findings underscore the pharmacological potential of withanolides as promising lead compounds for the development of novel anticancer therapeutics. 展开更多
关键词 Physalis angulata var.villosa Withanolide derivatives Isolation and identification ANTI-CANCER
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Amino acid derivatives as regulatory molecules:Mechanisms in plant growth and stress tolerance
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作者 Ning Ouyang Wenjuan Hu +1 位作者 Jieqiong Meng Bo Wang 《The Crop Journal》 2025年第3期668-680,共13页
Plants produce many amino acid derivatives(AADs).Some have been used by humans as medicines and nutrients,but many also act as phytochemical signals in plant growth and stress tolerance.The fluctuating ecological envi... Plants produce many amino acid derivatives(AADs).Some have been used by humans as medicines and nutrients,but many also act as phytochemical signals in plant growth and stress tolerance.The fluctuating ecological environment poses a constant challenge to plant growth and development,and also presents significant obstacles to agricultural productivity.Plant AADs hold substantial potential for agricultural applications to increase plant resilience against diverse biological and environmental pressures.In this review,we present recent advances in elucidating the biological roles of plant AADs in plant growth and stress tolerance and outline strategies for discovering novel AADs and their regulatory networks in crops.The review aims to gain new insights into the functional properties of AADs in regulating plant growth and stress responses,which provides a valuable foundation for developing innovative AADbased strategies to improve crop performance and resilience facing the ever-changing environment in the future. 展开更多
关键词 Amino acid derivatives Plant stress tolerance Crop resilience Phytochemical signaling Agricultural biotechnology
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Design and synthesis of novel saponin-triazole derivatives in the regulation of adipogenesis
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作者 Yongsheng Fang Zhiyun Zhu +7 位作者 Chun Xie Dazhen Xia Huimin Zhao Zihui Wang Qian Lu Caimei Zhang Wenyong Xiong Xiaodong Yang 《Chinese Journal of Natural Medicines》 2025年第8期920-931,共12页
Saponins associated with Panax notoginseng(P.notoginseng)demonstrate significant therapeutic efficacy across multiple diseases.However,certain high-yield saponins face limited clinical applications due to their reduce... Saponins associated with Panax notoginseng(P.notoginseng)demonstrate significant therapeutic efficacy across multiple diseases.However,certain high-yield saponins face limited clinical applications due to their reduced pharmacological efficacy.This study synthesized and evaluated 36 saponin-1,2,3-triazole derivatives of ginsenosides Rg1/Rb1 and notoginsenoside R1 for anti-adipogenesis activity in vitro.The research revealed that the ginsenosides Rg1-1,2,3-triazole derivative a17 demonstrates superior adipogenesis inhibitory effects.Structure-activity relationships(SARs)analysis indicates that incorporating an amidyl-substituted 1,2,3-triazole into the saponin side chain via Click reaction enhances anti-adipogenesis activity.Additionally,several other derivatives exhibit general adipogenesis inhibition.Compound a17 demonstrated enhanced potency compared to the parent ginsenoside Rg1.Mechanistic investigations revealed that a17 exhibits dose-dependent inhibition of adipogenesis in vitro,accompanied by decreased expression of preadipocytes.Peroxisome proliferator-activated receptorγ(PPARγ),fatty acid synthase(FAS),and fatty acid binding protein 4(FABP4)adipogenesis regulators.These findings establish the ginsenoside Rg1-1,2,3-triazole derivative a17 as a promising adipocyte differentiation inhibitor and potential therapeutic agent for obesity and associated metabolic disorders.This research provides a foundation for developing effective therapeutic approaches for various metabolic syndromes. 展开更多
关键词 Panax notoginseng Saponin-triazole derivatives Adipocyte differentiation and maturation Lipid metabolism Structure-activity relationships
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Goji berry-derived phenylpropionyl phenylethylamine derivatives protect against ethanol-induced hepatic damage
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作者 Zhengqun Zhou Zhaodi Che +7 位作者 Jiancong Mai Rui Zhang Zhihui Luo Yifang Li Kwokfai So Jia Xiao Xinsheng Yao Hao Gao 《Food Science and Human Wellness》 2025年第3期1139-1147,共9页
Goji berry is a famous edible and medicinal substance around the world.In this research,15 phenylpropionyl phenylethylamine derivatives(1-15),in cluding one new compound(1),were separated and identified from g oji ber... Goji berry is a famous edible and medicinal substance around the world.In this research,15 phenylpropionyl phenylethylamine derivatives(1-15),in cluding one new compound(1),were separated and identified from g oji berry.All isolates were elucidated via ex tensive nuclear magnetic resonance spectral analyses and chemical techniques.Six known isolates were first obtained from Lycium genus.Six isolates were effectively split in to double chromatographic peaks accompanied by the basically identical areas,indicating they belong to racemates.The oxygen radical absorbance capacity(ORAC)experiment indicated that all isolates displayed a capacity of scavenging free radicals,and most of them exhibited higher ORAC than epigallocatechingallate.In ethanol/palmitic acid-established in vitro hepatocyte injury model,four phenylpropionyl phenylethylamine derivatives(1,2,9,and 15)significantly alleviated hepatocyte injury,among which compound 1 exerted the strongest protective activity.Notably,the hepatoprotective effect of compound 1 was further confirmed in ethanol-established liver damage mouse model,reflected by the reduction of lipid accumulation and the attenuation of pathological alteration.Combined with the in vitro results,the in vivo observations suggested that compound 1 suppressed cell apoptosis and the outburst of inflammation.Our findings provided first-hand evidence proving that goji berry-derived phenylpropionyl phenylethylamine derivatives hold a potential in treating alcoholic liver disease. 展开更多
关键词 Goji berry Lycium barbarum Phenylpropionyl phenylethylamine derivatives Antioxidant activity He patoprotective effect
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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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