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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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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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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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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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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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FTIR Spectroscopic Study of Thioanisole and its Two Halogenated Derivatives
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作者 Jiaqi Xin Jianzhi Xu +5 位作者 Ya-Ke Li Jianbao Zhao Brant EBillinghurst Hong Gao Ziqiu Chen Gao-Lei Hou 《Chinese Journal of Chemical Physics》 2025年第5期587-596,I0005-I0028,I0147,I0148,共36页
The rovibrational spectra of thioanisole(TA)and its halogenated derivatives,3-fluorothioanisole(3FTA)and 3-chlorothioanisole(3ClTA),were measured using synchrotron-based Fourier transform infrared spectroscopy(FTIR)at... The rovibrational spectra of thioanisole(TA)and its halogenated derivatives,3-fluorothioanisole(3FTA)and 3-chlorothioanisole(3ClTA),were measured using synchrotron-based Fourier transform infrared spectroscopy(FTIR)at the Canadian Light Source.Combined with density functional theory calculations,the stable structures and vibrational modes of TA,3FTA,and 3ClTA in their vibrational states were analyzed.The theoretical vibrational mode frequencies were corrected by simulating the rotational structure of a vibrational band.The contributions of the cis-and trans-isomers of 3FTA and 3ClTA to the FTIR spectra at 298 K were estimated using the Boltzmann distribution,revealing their coexistence in the experimental spectra.The results indicate that both fluorine and chlorine substitution significantly affect the vibrational modes,particularly in the benzene ring.Compared to TA,the FTIR spectra of 3FTA and 3ClTA show changes in the frequencies and intensities of some vibrational modes,with halogen substitution causing specific modes to shift to higher wavenumbers.A comparison of the FTIR spectra of TA,3FTA,and 3ClTA highlights the influence of halogen substitution on vibrational properties,emphasizing how the type and position of the substituent affect frequency shifts and spectral intensities.These findings provide deeper insights into how halogenation alters vibrational spectra,which is crucial for further spectral analysis and molecular structure determination. 展开更多
关键词 Fourier transform infrared spectroscopy THIOANISOLE Halogenated derivatives
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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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Validation Analysis of Gas Chromatography Method for Determining 8 Benzene Derivatives in Fixed Pollution Source Exhaust Gas
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作者 Wenshuai XU Juan LI Ziyan LIN 《Meteorological and Environmental Research》 2025年第4期37-39,42,共4页
Benzene derivatives are volatile organic compounds commonly present in the atmospheric environment,which are toxic and complex in composition.They have become a key regulatory object in China s atmospheric environment... Benzene derivatives are volatile organic compounds commonly present in the atmospheric environment,which are toxic and complex in composition.They have become a key regulatory object in China s atmospheric environment management.In this paper,Shimadzu Nexis GC-2030 gas chromatography was used to simultaneously detect eight benzene derivatives.According to the Environmental Monitoring—Technical Guideline on Drawing and Revising Analytical Method Standards(HJ 168-2010),the monitoring methods for benzene,toluene,ethylbenzene,p-xylene,m-xylene,isopropylbenzene,o-xylene,and styrene in the Stationary Source Emission—Determination of Benzene and Its Analogies—Bags Sampling/Direct Injection—Gas Chromatography(HJ 1261-2022)are verified,and their linear relationships,detection limits,precision and accuracy are analyzed. 展开更多
关键词 Benzene derivatives Fixed pollution source exhaust gas Method validation
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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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