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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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Higher-order optimality conditions for multiobjective optimization through a new type of directional derivatives
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作者 HUANG Zheng-gang 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期543-557,共15页
This paper deals with extensions of higher-order optimality conditions for scalar optimization to multiobjective optimization.A type of directional derivatives for a multiobjective function is proposed,and with this n... This paper deals with extensions of higher-order optimality conditions for scalar optimization to multiobjective optimization.A type of directional derivatives for a multiobjective function is proposed,and with this notion characterizations of strict local minima of order k for a multiobjective optimization problem with a nonempty set constraint are established,generalizing the corresponding scalar case obtained by Studniarski[3].Also necessary not sufficient and sufficient not necessary optimality conditions for this minima are derived based on our directional derivatives,which are generalizations of some existing scalar results and equivalent to some existing multiobjective ones.Many examples are given to illustrate them there. 展开更多
关键词 strict local minima of order k multiobjective optimization higher-order optimality conditions higher-order directional derivatives
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Extended Dissipaton Theory for Higher-Order Bath Couplings and Application to Non-Condon Spectroscopy with Anharmonicity
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作者 Zi-Fan Zhu Yu Su +2 位作者 Yao Wang Rui-Xue Xu YiJing Yan 《Chinese Journal of Chemical Physics》 2026年第1期67-72,I0043,共7页
In this work,we develop an extended dissipaton theory that generalizes the environmental couplings beyond the conventional linear and quadratic forms,enabling the treatment of ar-bitrary order of bath couplings.Ap-ply... In this work,we develop an extended dissipaton theory that generalizes the environmental couplings beyond the conventional linear and quadratic forms,enabling the treatment of ar-bitrary order of bath couplings.Ap-plying this theoretical framework to the condensed-phase non-Condon spectroscopy,we demonstrate the in-terplay of anharmonicity,non-Con-don and solvent effects on optical spectra,where the higher-order cou-plings arise from the anharmonicity of nuclear potential surface of the excited state.Precise simulations are carried out with high efficiency on linear absorption spectra involving the above mentioned correlated effects.We exhibit how an anharmonic potential modulates the vibronic feature,offering insights into the role of nonlinear environmental couplings in spectroscopic signatures and exemplifying the success of the extended dissipaton formalism as an exact and efficient method for higher-or-der bath couplings. 展开更多
关键词 Quantum dissipation higher-order nonlinear bath couplings Anharmonic and non-Gaussian bath Non-Condon spectroscopy
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Research progress of 3-n-butylphthalide and its derivatives in combating cerebral ischemia
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作者 Hongwei Zheng Yangyang Jiang +7 位作者 Kai Wang Xiao Liu Zihan Jia Xing Su Yanan Zhang Yihua Zhang Zhangjian Huang Yong Ling 《Chinese Journal of Natural Medicines》 2026年第1期13-22,共10页
Ischemic stroke(IS)presents a major threat to human life and health due to its high disability and mortality rates.3-n-Butylphthalide(NBP),derived from celery seeds of the Apiaceae family native to the Mediterranean r... Ischemic stroke(IS)presents a major threat to human life and health due to its high disability and mortality rates.3-n-Butylphthalide(NBP),derived from celery seeds of the Apiaceae family native to the Mediterranean region,was first introduced in China for acute IS treatment in 2004.NBP demonstrates multiple therapeutic actions,including reconstruction of microcirculation in the cerebral ischemia area,inhibition of platelet aggregation,reduction of cerebral infarction volume,maintenance of blood-brain barrier(BBB)integrity,and enhancement of cerebral blood perfusion.However,its overall efficacy remains moderate,limited by poor water solubility and low bioavailability,which constrains its clinical application.To address these limitations,researchers have actively pursued the development of NBP derivatives and analogs,achieving notable progress.These efforts,including substituent introduction,ring opening derivatization,esterification,and atom substitution,have generated diverse NBP derivatives.Several of these derivatives have advanced to clinical studies.Specifically,potassium 2-(1-hydroxypentyl)-benzoate(PHPB),brozopentyl sodium(BZP),and XY-03-EA(ZONK1103)have reached phase II clinical trials,while(S)-2-(1-acetoxypentyl)benzoic acid L-arginine salt(AAPB)has received clinical trial approval for 2024.This review examines the structural modification and optimization of NBP over the past two decades from a medicinal chemistry perspective,aiming to facilitate the development of superior derivatives and advance cerebral ischemia treatment. 展开更多
关键词 Ischemic stroke 3-N-BUTYLPHTHALIDE derivativeS Structural modification Cerebral ischemia
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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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Electrochromic Devices with High Stability from Colorless to Green Conversion Based on Viologen Derivatives
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作者 PENG Yuyi QIAN Chao +3 位作者 WANG Peng GUO Xu JIANG Chuanyu LIU Ping 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期258-267,共10页
Two viologen derivatives containing fluorine substituent(F)with an asymmetric structures,1,1'-bis(4-(trifluoromethyl)phenyl)-[4,4'-bipyridine]dihexafluorophosphate(DFPV)and 1-benzyl-1'-(4-(trifluoromethyl)... Two viologen derivatives containing fluorine substituent(F)with an asymmetric structures,1,1'-bis(4-(trifluoromethyl)phenyl)-[4,4'-bipyridine]dihexafluorophosphate(DFPV)and 1-benzyl-1'-(4-(trifluoromethyl)phenyl)-[4,4'-bipyridine]di-hexafluorophosphate(Bn-FPV),were synthesized.These viologen derivatives as active materials were used to assemble both flexible and rigid electrochromic devices(ECDs).ECDs based on DFPV exhibited reversible color change from colorless to deep green and ECDs based on Bn-FPV exhibited reversible color change from colorless to blue-green within applied voltage.It was found that the devices based on DFPV showed cycle stability,which could still maintain more than 90% after 1000 cycles.In addition,the modulation rate of the device to the solar irradiance is also calculated to characterize its application potential in smart windows.Among them,the rigid device(R-DFPV)based on the DFPV has a large solar irradiance modulation rate of 54.66%,which has the potential to be used as smart windows. 展开更多
关键词 viologen derivatives electrochromic material flexible electrochromic devices rigid electrochromic device smart windows
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A NIR and ratiometric fluorescent probe for quantitative detection of SO_(2) derivatives in Chinese medicinal materials and bioimaging in vivo
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作者 Meitong Wu Ke Wu +7 位作者 Shumin Feng Li Xu Mi Lei Jianmei Chen Shuang Li Mian Qin Dahui Liu Guoqiang Feng 《Chinese Chemical Letters》 2026年第1期434-439,共6页
Sulfur dioxide(SO_(2)) and its derivatives have been recognized as harmful environmental pollutants.However,they are often produced during the processing of traditional Chinese medicines,potentially compromising the q... Sulfur dioxide(SO_(2)) and its derivatives have been recognized as harmful environmental pollutants.However,they are often produced during the processing of traditional Chinese medicines,potentially compromising the quality of these medicinal materials and contributing to various health issues.Due to a lack of effective monitoring and imaging tools,the physiological effects of excessive SO_(2) residues in traditional Chinese medicine remain unclear.Therefore,developing a rapid and effective tool for detecting SO_(2) is crucial for understanding its metabolic pathways and effects in vivo.In this study,we developed a near infrared(NIR) and ratiometric fluorescent probe,NIR-RS,which exhibits high sensitivity,selectivity,and rapid response for SO_(2) detection.Notably,NIR-RS accurately quantifies SO_(2) contents in Pinelliae rhizoma(P.rhizoma) samples,with recovery rates from 98.46 % to 102.40 %,and relative standard deviations(RSDs)< 5.0 %.For bioimaging applications,NIR-RS has low cytotoxicity and good mitochondrial-targeting ability,making it suitable for imaging exogenous and endogenous SO_(2) in mitochondria.Additionally,NIR-RS was successfully applied to image SO_(2) content of P.rhizoma samples within cells,revealing that high SO_(2) residue elevated mitochondria adenosine triphosphate(ATP) content,these findings reveal that P.rhizoma with excessive SO_(2) can affect the organism's growth mechanisms through alterations in ATP pathways.In vivo,SO_(2) was found to predominantly accumulate in the liver following gavage with P.rhizoma solution,with accumulation levels increasing in proportion to SO_(2) residue concentration.High SO_(2) concentrations in P.rhizoma can cause pulmonary fibrosis and gastric mucosal damage.This work provides a valuable tool for regulating SO_(2) content in P.rhizoma and may help researcher better understand the metabolism of SO_(2) derivatives and explore their physiological roles in biological systems. 展开更多
关键词 Fluorescent probe SO_(2)derivatives metabolism Quantitative analysis Pinelliae rhizoma Fluorescent imaging
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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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Pyrazino[2,3-f][1,10]phenanthroline Derivatives as Photoredox Catalysts for Photoinduced Organocatalyzed Atom Transfer Radical Polymerization(O-ATRP)at ppm-Level Loading
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作者 Wen-Zhe Xu Wan-Chao Hu +1 位作者 Bei Liu Chang-Li Lü 《Chinese Journal of Polymer Science》 2026年第3期664-674,I0009,共12页
Organocatalyzed atom transfer radical polymerization(O-ATRP)is a pivotal technique for the synthesis of polymers with well-defined structures that are devoid of metallic residues.A major challenge in this area is the ... Organocatalyzed atom transfer radical polymerization(O-ATRP)is a pivotal technique for the synthesis of polymers with well-defined structures that are devoid of metallic residues.A major challenge in this area is the reduction of catalyst loading while maintaining precise control over polymer architecture and properties.Herein,we systematically evaluate the efficacy of six pyrazino[2,3-f][1,10]phenanthroline(pyzPhen)-based photoredox catalysts in photoinduced O-ATRP.Experimental results indicate that the introduction of various substituents markedly influences the photophysical properties and redox behavior of the catalysts,thereby resulting in differing catalytic efficiencies in the O-ATRP of methyl methacrylate(MMA).Following additional optimization,two highly efficient O-ATRP photocatalysts capable of exhibiting thermally activated delayed fluorescence(TADF)were successfully identified.Under visible light irradiation,TADF catalysts effectively mediated the controlled polymerization of MMA at a low loading level of 50 ppm,particularly when used in conjunction with the initiator DBMM.The catalytic systems demonstrate excellent temporal control,broad monomer applicability,and favorable compatibility with various initiators and solvent systems.This work offers new insights into the development of efficient,low-catalyst-loading,metal-free ATRP systems. 展开更多
关键词 Organocatalyzedatom transfer radical polymerization(O-ATRP) Photoredox catalysts Pyrazino[2 3-f][1 10]phenanthroline derivatives Thermally activated delayed fluorescence(TADF) Low catalyst loading
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Optimality conditions in set optimization employing higher-order radial derivatives
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作者 YU Guo-lin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第2期225-236,共12页
There are two approaches of defining the solutions of a set-valued optimization problem: vector criterion and set criterion. This note is devoted to higher-order optimality conditions using both criteria of solutions... There are two approaches of defining the solutions of a set-valued optimization problem: vector criterion and set criterion. This note is devoted to higher-order optimality conditions using both criteria of solutions for a constrained set-valued optimization problem in terms of higher-order radial derivatives. In the case of vector criterion, some optimality conditions are derived for isolated (weak) minimizers. With set criterion, necessary and sufficient optimality conditions are established for minimal solutions relative to lower set-order relation. 展开更多
关键词 higher-order radial derivative optimality conditions set-valued optimization vector criterion set criterion.
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Dynamics analysis of higher-order soliton solutions for the coupled mixed derivative nonlinear Schrodinger equation
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作者 Ni Song Yuxiang Lei Dongxing Cao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第5期159-165,I0004,共8页
In this paper,the dynamics of the higher-order soliton solutions for the coupled mixed derivative nonlinear Schrodinger equation¨are investigated via generalized Darboux transformation.Given a pair of linearly in... In this paper,the dynamics of the higher-order soliton solutions for the coupled mixed derivative nonlinear Schrodinger equation¨are investigated via generalized Darboux transformation.Given a pair of linearly independent solutions of the Lax pair,the oneto three-soliton solutions are obtained via algebraic iteration.Furthermore,two and three solitons are respectively displayed via numerical simulation.Moreover,the dynamics of solitons are illustrated with corresponding evolution plots,such as elastic collisions,inelastic collisions,and bound states.It is found that there are some novel phenomena of interactions among solitons,which may provide a theoretical basis for studying optical solitons in experiments. 展开更多
关键词 Coupled mixed derivative nonlinear Schrodinger equation Generalized Darboux transformation SOLITON Inelastic colli-osions Bound states
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Novel Bipolar Hosts for Solution-processable Green Phosphorescent OLEDs Based on Tetrasubstituted Carbazole Derivatives 被引量:2
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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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Optimal Synchronization of Higher-Order Dynamical Networks 被引量:2
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作者 Guanrong CHEN 《Artificial Intelligence Science and Engineering》 2025年第1期31-36,共6页
This article briefly reviews the topic of complex network synchronization,with its graph-theoretic criterion,showing that the homogeneous and symmetrical network structures are essential for optimal synchronization.Fu... This article briefly reviews the topic of complex network synchronization,with its graph-theoretic criterion,showing that the homogeneous and symmetrical network structures are essential for optimal synchronization.Furthermore,it briefly reviews the notion of higher-order network topologies and shows their promising potential in application to evaluating the optimality of network synchronizability. 展开更多
关键词 complex network SYNCHRONIZATION optimal synchronizability SIMPLEX higher-order topology
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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:2
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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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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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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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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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A New Technique for Constructing Higher-order Iterative Methods to Solve Nonlinear Systems
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作者 XIAO Xiaoyong 《应用数学》 北大核心 2025年第3期762-774,共13页
In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introduc... In this paper,a new technique is introduced to construct higher-order iterative methods for solving nonlinear systems.The order of convergence of some iterative methods can be improved by three at the cost of introducing only one additional evaluation of the function in each step.Furthermore,some new efficient methods with a higher-order of convergence are obtained by using only a single matrix inversion in each iteration.Analyses of convergence properties and computational efficiency of these new methods are made and testified by several numerical problems.By comparison,the new schemes are more efficient than the corresponding existing ones,particularly for large problem sizes. 展开更多
关键词 Systems of nonlinear equation Order of convergence higher-order method Extended Newton iteration Computational efficiency
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One-Pot Transition-Metal-Free Synthesis of Carboline Derivatives via Dual C-N Bond Formation
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作者 Xie Guiling Mopuri Sudhakar Reddy +2 位作者 Li Jie Yang Yuanyong Chen Tie-Gen 《有机化学》 北大核心 2025年第10期3824-3837,共14页
A transition-metal-free strategy for the synthesis of carboline derivatives via sequential dual C—N bond formation in a one-pot reaction is reported.Using 2,2'-dihalogenated pyridyl biaryls and primary amines as ... A transition-metal-free strategy for the synthesis of carboline derivatives via sequential dual C—N bond formation in a one-pot reaction is reported.Using 2,2'-dihalogenated pyridyl biaryls and primary amines as starting materials,this method efficiently constructs a series ofα-,β-,γ-andδ-carbolines under alkaline conditions.The reaction proceeds smoothly in the presence of lithium tert-butoxide(t-BuOLi)or cesium carbonate(Cs_(2)CO_(3))without requiring transition metal catalysts,demonstrating good functional group tolerance.This approach enables gram-scale synthesis and has been successfully applied to the preparation of the organic material 2,6-CbPy,achieving high conversion efficiency. 展开更多
关键词 carboline derivatives primary amines transition-metal-free dual C-N bond formation one-pot reaction
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