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Soil colloids can significantly enhance spreading of polybromodiphenyl ethers in groundwater by serving as an effective carrier 被引量:1
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作者 Lin Duan Min Li +1 位作者 Jiameng Liu Wei Chen 《Journal of Environmental Sciences》 2025年第1期93-100,共8页
Polybromodiphenyl ethers(PBDEs),the widely used flame retardants,are common contaminants in surface soils at e-waste recycling sites.The association of PBDEs with soil colloids has been observed,indicating the potenti... Polybromodiphenyl ethers(PBDEs),the widely used flame retardants,are common contaminants in surface soils at e-waste recycling sites.The association of PBDEs with soil colloids has been observed,indicating the potential risk to groundwater due to colloid-facilitated transport.However,the extent to which soil colloidsmay enhance the spreading of PBDEs in groundwater is largely unknown.Herein,we report the co-transport of decabromodiphenyl ester(BDE-209)and soil colloids in saturated porous media.The colloids released froma soil sample collected at an e-waste recycling site in Tianjin,China,contain high concentration of PBDEs,with BDE-209 being the most abundant conger(320±30 mg/kg).The colloids exhibit relatively high mobility in saturated sand columns,under conditions commonly observed in groundwater environments.Notably,under all the tested conditions(i.e.,varying flow velocity,pH,ionic species and ionic strength),the mass of eluted BDE-209 correlates linearly with that of eluted soil colloids,even though the mobility of the colloids varies markedly depending on the specific hydrodynamic and solution chemistry conditions involved.Additionally,the mass of BDE-209 retained in the columns also correlates strongly with themass of retained colloids.Apparently,the PBDEs remain bound to soil colloids during transport in porous media.Findings in this study indicate that soil colloidsmay significantly promote the transport of PBDEs in groundwater by serving as an effective carrier.This might be the reason why the highly insoluble and adsorptive PBDEs are found in groundwater at some PBDE-contaminated sites. 展开更多
关键词 Polybromodiphenyl ethers Soil colloids E-waste recycling sites GROUNDWATER Facilitated transport
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Study on Gold Self-Relay Catalytic Annulation/Nucleophilic Substitu-tion of 1,3-Enyne Acetates with Cyclic Ether Acetals
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作者 Zhang Congyu Chen Xiaoqi +3 位作者 Meng Fantao Wang Haiying Hao Wen-Juan Jiang Bo 《有机化学》 北大核心 2025年第6期2199-2207,共9页
A new gold self-relay catalytic annulation/nucleophilic substitution cascade of 1,3-enyne acetates with cyclic ether acetals is reported,enabling highly diastereoselective access to cyclic etherified cyclopentenones w... A new gold self-relay catalytic annulation/nucleophilic substitution cascade of 1,3-enyne acetates with cyclic ether acetals is reported,enabling highly diastereoselective access to cyclic etherified cyclopentenones with cyclic quaternary centers in moderate to good yields and>19∶1 dr.This catalysis enables the direct construction of two types of carboncyclic skeletons by adjusting the olefin types of 1,3-enyne acetates.When 1,3-enyne acetates bearing a cyclic alkene unit were used,5~6 fused bicarbocyclic products were diastereoselectively synthesized,whereas the reaction of acyclic 1,3-enyne acetates resulted in five-memebered carbocyclic framework.Notably,cyclic ether acetals are commonly used as protecting groups in traditional multistep organic syntheses,and in this reaction,such reagents serve as electrophilic cyclic ether precursors,achieving new uses for old reagents.The current method demonstrates good functional group compatibility,a broad substrate scope and high diastereoselectivity,providing a new synthetic strategy toward functionalized cyclopentenones. 展开更多
关键词 gold self-relay catalysis Nazarov cyclization nucleophilic substitution 1 3-enyne acetates cyclic ether acetals
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The synthesis of alcohol ether esters through the catalytic hydrogenation of diethyl oxalate in the Cu-Al systems induced by Al_(2)O_(3) properties
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作者 Peng Wu Lina Ma +3 位作者 Yu Zheng Li Luo Lihong Su Juntian Li 《日用化学工业(中英文)》 北大核心 2025年第9期1100-1111,共12页
The structure-performance relationship of Cu/Al_(2)O_(3) catalysts in the hydrogenation of diethyl oxalate(DEO)for the synthesis of alcohol ether esters has been investigated by various characterization techniques inc... The structure-performance relationship of Cu/Al_(2)O_(3) catalysts in the hydrogenation of diethyl oxalate(DEO)for the synthesis of alcohol ether esters has been investigated by various characterization techniques including XRD,XPS,N2O titration,and 27Al MAS-NMR.The results showed that when the crystal configurations of Al_(2)O_(3) were the same,increasing the specific surface area could effectively refine the size of copper nanoparticles(Cu NPs),and ultimately improve the conversion of DEO.Meanwhile,the smaller size ofγ-Al_(2)O_(3)(HSAl and SBAl)loaded Cu NPs promotes the reaction towards the deep hydrogenation to produce ethanol(EtOH)and ethylene glycol(EG).Besides,the larger size of Cu NPs on the surface of amorphous Al_(2)O_(3)(HTAl and SolAl)resulted in a lower conversion rate,where ethyl glycolate(Egly)is the main product.Despite there are differences in Al^(3+)ionic coordination in Al_(2)O_(3) with different crystal structures,the experimental data showed that the differences in Al^(3+)ionic coordination did not significantly affect the catalytic performance in the hydrogenation reaction.The formation of alcohol-ether ester chemicals is critically dependent on the interactions between Cu sites and acidic sites.Among them,EG and EtOH were dehydrated to form 2-ethoxyethanol via the SN2 mechanism,while Egly and EtOH were reacted to form ethyl ethoxyacetate(EEA)via the SN2 mechanism.This study provides a theoretical basis for the optimization of the coal-based glycol processes to achieve a diversified product portfolio. 展开更多
关键词 oxalate hydrogenation alcohol ether esters Cu-Al catalyst SN2 mechanism
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Discovery of diphenyl ethers as novel inhibitors of insect trehalase via virtual screening and biological assays
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作者 Xi Jiang Wenda Li +6 位作者 Qiong Lu Yi Ding Mingjia Gao Shanru He Wei Liu Yong Zhou Tian Liu 《Advanced Agrochem》 2025年第4期342-348,共7页
Trehalase hydrolyzes trehalose to glucose to provide energy for insects or building blocks for chitin synthesis.Because trehalase is critical to insects but not to humans,it has long been considered a promising target... Trehalase hydrolyzes trehalose to glucose to provide energy for insects or building blocks for chitin synthesis.Because trehalase is critical to insects but not to humans,it has long been considered a promising target for green insecticides.However,the known trehalase inhibitors are mainly sugar derivatives with poor druggability.In this study,the trehalase from Ostrinia furnacalis(OfTreh)was expressed and characterized.By integrative computational strategies,diphenyl ether herbicides were discovered as the first non-carbohydrate inhibitors of insect trehalases.Bifenox and its more stable derivative,chlomethoxyfen,inhibited Of Treh with Ki values of 56 and 43μM,respectively.The oral administration of bifenox or chlomethoxyfen to locusts resulted in the inhibition of trehalose hydrolysis in vivo,leading to a mortality rate of 66%and server locomotion disorder in the survivors.This study not only established a platform for the development of insecticides targeting trehalase but also discovered a new mechanism for diphenyl ethers to kill insects as trehalase inhibitors. 展开更多
关键词 TREHALASE INHIBITOR Virtual screening INSECTICIDE Diphenyl ethers
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Enhanced selective oxidation of dimethyl ether to formaldehyde by MoO_(3)-Fe_(2)(MoO_(4))_(3) interaction over iron-molybdate catalysts
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作者 Yafei Liang Yuji Qi +6 位作者 Mingli Bi Zhen Shi Junju Mu Shushuang Li Jian Zhang Yehong Wang Feng Wang 《Journal of Energy Chemistry》 2025年第7期832-841,共10页
The efficient catalytic conversion of fossil-based low-carbon small molecules to oxygen-containing chemicals is an attractive research topic in the fields of energy and chemical engineering.The selective oxidation of ... The efficient catalytic conversion of fossil-based low-carbon small molecules to oxygen-containing chemicals is an attractive research topic in the fields of energy and chemical engineering.The selective oxidation of dimethyl ether(DME),which is derived from fossil resources,represents a promising approach to producing high-concentration formaldehyde with low energy consumption.However,there is still a lack of catalysts achieving satisfactory conversion of DME with high selectivity for formaldehyde under mild conditions.In this work,an efficient iron-molybdate(FeMo)catalyst was developed for the selective oxidation of DME to formaldehyde.The DME conversion of 84% was achieved with a superior formaldehyde selectivity(77%)at 300℃,a performance that is superior to all previously reported results.In an approximately 550 h continuous reaction,the catalyst maintained a conversion of 64% and a formaldehyde selectivity of 79%.Combined X-ray diffraction(XRD),Transmission electron microscope(TEM),Ultraviolet-visible spectroscopy(UV-Vis),Hydrogen temperature-programmed reduction(H_(2)-TPR),Fourier transform infrared(FT-IR)analyses,along with density functional theory(DFT)calculations,demonstrated that the excellent FeMo catalyst was composed of active Fe_(2)(MoO_(4))_(3)and MoO_(3)phases,and there was an interaction between them,which contributed to the efficient DME dissociation and smooth hydrogen spillover,leading to a superior DME conversion.With the support of DME/O_(2)pulse experiments,in-situ Raman,in-situ Dimethyl ether infrared spectroscopy(DME-IR)and DFT calculation results,a Mars-van Krevelen(MvK)reaction mechanism was proposed:DME was dissociated on the interface between Fe_(2)(MoO_(4))_(3)and MoO_(3)phases to form active methoxy species firstly,and it dehydrogenated to give hydrogen species;the generated hydrogen species smoothly spilled over from Fe_(2)(MoO_(4))_(3)to MoO_(3)enhanced by the interaction between Fe_(2)(MoO_(4))_(3)and MoO_(3);then the hydrogen species was consumed by MoO_(3),leading to a reduction of MoO_(3),and finally,the reduced MoO_(3)was re-oxidized by O_(2),returning to the initial state.These findings offer valuable insights not only for the development of efficient FeMo catalysts but also for elucidating the reaction mechanism involved in the oxidation of DME to formaldehyde,contributing to the optimized utilization of DME derived from fossil resources. 展开更多
关键词 Dimethyl ether Selective oxidation FeMo catalyst FORMALDEHYDE INTERACTION
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Research progress on lithium isotopes separation by chemical exchange with crown ethers decorated materials
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作者 Yi Fang Rui Ha +3 位作者 Jun Sun Xue Liu Xiang Dong Ding Wei Qun Shi 《Green Energy & Environment》 2025年第3期441-451,共11页
The separation of lithium isotopes (^(6)Li and ^(7)Li) is of great importance for the nuclear industry.The lithium amalgam method is the only lithium isotopes separation process in industry,and the extensive use of me... The separation of lithium isotopes (^(6)Li and ^(7)Li) is of great importance for the nuclear industry.The lithium amalgam method is the only lithium isotopes separation process in industry,and the extensive use of mercury has raised concerns about its potential environmental hazards,which have prompted the search for more efficient and environmentally friendly alternatives.Crown ethers can bind lithium ions highly selectively and separate lithium isotopes effectively.A chemical exchange-based lithium isotopes separation method using crown ether decorated materials could be a viable and cost-effective alternative to the lithium amalgam method.In this review,we provide a systematic summary of the recent advances in lithium isotopes separation using crown ethers decorated materials. 展开更多
关键词 Lithium isotopes SEPARATION Crown ether Chemical exchange
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Metal/H^(+)sites modulation in the decatungstate+Pd/C catalytic system for photocatalytic generation of furfuryl ethyl ether
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作者 Zheng Li Ying Zeng +2 位作者 Yuanyuan Dong Hongjin Lv Guo-Yu Yang 《Chinese Journal of Catalysis》 2025年第8期137-146,共10页
Furfuryl ethyl ether(FEE)is considered as one of the most important candidates for biofuels due to its high-octane number.However,it is still challenging to produce FEE via the biomass-based route under mild condition... Furfuryl ethyl ether(FEE)is considered as one of the most important candidates for biofuels due to its high-octane number.However,it is still challenging to produce FEE via the biomass-based route under mild conditions.Here,we developed a photoinduced catalytic transfer hydrogenation(CTH)process for the efficient production of FEE through the reduction etherification of furfural(FF)using Na_(4)W_(10)O_(32)(NaDT),Pd/C,and ethanol as the hydrogen atom transfer(HAT)catalyst,hydrogenation catalyst,and the H donor,respectively.Notably,the introduction of brominated benzene(PhBr)as an additive significantly promoted the yield of FEE to 92.7%.A series of experiments and characterization results indicated that the attachment and detachment of Br atoms on Pd/C catalyst surface effectively regulate the balance between H^(+)sites and Pd sites in the NaDT+Pd/C catalytic system.The balance facilitates the preferential acetalization of FF catalyzed by H^(+)sites,followed by hydrogenation to efficiently produce FEE catalyzed by Pd sites.This photoinduced CTH process exhibits good stability and recyclability as well as universality for the transformation of various organic substrates under mild conditions. 展开更多
关键词 Furfuryl ether DECATUNGSTATE Photocatalysis Catalytic transfer hydrogenation Biomass valorization
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Kinetic and process analysis of continuous catalytic distillation for high-purity propylene glycol monomethyl ether acetate production
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作者 Qinglian Wang Dingbang Zhao +5 位作者 Huaifang Li Xin Gao Weifeng Shen Chen Yang Changshen Ye Ting Qiu 《Chinese Journal of Chemical Engineering》 2025年第10期200-210,共11页
The production of high-purity propylene glycol monomethyl ether acetate(PMA)through the transesterification of propylene glycol monomethyl ether(PM)and methyl acetate(MeOAc)is traditionally catalyzed by sodium methoxi... The production of high-purity propylene glycol monomethyl ether acetate(PMA)through the transesterification of propylene glycol monomethyl ether(PM)and methyl acetate(MeOAc)is traditionally catalyzed by sodium methoxide.However,the practical application of this method is significantly hindered by the inherent limitations of sodium methoxide,such as its high sensitivity to moisture and propensity for solid precipitation,which impede its effective use in continuous processes.This work proposed a continuous catalytic distillation(CD)process utilizing Amberlyst 15 cation exchange resin as the catalyst.A comprehensive series of reaction kinetic and CD experiments were conducted to evaluate the performance of the proposed process.The results demonstrate that under the optimal operating conditions,namely an ester-to-ether molar ratio of 6:1,a refluxratio of 5:1,a total feed rate of 0.92 g‧min^(-1),and an evaporation rate of 266.47 m^(3)‧m^(-2)‧h^(-1),the conversion rate of PM achieves 99.95%,and the PMA yield is 97.31%.Based on these findings,a process flowsheet for a continuous CD process tailored for the production of electronic-grade PMA is presented.This design incorporates light and heavy removal steps to ensure the production of PMA with a purity of 99.99%.Additionally,the process utilizes pressure swing distillation to recover MeOAc,thereby enhancing the overall efficiencyand sustainability of the production process.The proposed continuous CD process offers a highly efficient,cost-effective,and environmentally sustainable solution for the production of electronic-grade PMA. 展开更多
关键词 Propylene glycol monomethyl ether acetate Reactive distillation CATALYST KINETIC Electronic-grade
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Regulating electric double layer in non-fluorinated ether electrolyte enables high-voltage and low-temperature lithium metal batteries
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作者 Renfei Zhao Yuanhang Gao +7 位作者 Zuosu Qin Yuelin Li Tao Zhang Anqiang Pan Ning Zhang Renzhi Ma Xiaohe Liu Gen Chen 《Advanced Powder Materials》 2025年第3期110-119,共10页
The poor oxidation stability of ether-based solvents has long been a major challenge limiting their practical application.To enhance the oxidative stability of ether-based electrolytes,the physicochemical properties o... The poor oxidation stability of ether-based solvents has long been a major challenge limiting their practical application.To enhance the oxidative stability of ether-based electrolytes,the physicochemical properties of various glycol dimethyl ethers are screened,and diglyme(G2)is selected as the sole solvent for the electrolyte.Lithium bis(fluorosulfonyl)imide(LiFSI),a highly dissociative salt,is used as the primary salt;while lithium nitrate(LiNO_(3))and lithium difluorophosphate(LiDFP),which have small ionic sizes and strong binding energies,are added as secondary salts.The resulting electrolyte can modulate the electric double layer structure by NO_(3)^(-) and DFP^(-) on the cathode side,leading to an increased Liþconcentration that is originally repelled by the cathode.Additionally,the oxidation stability of the electrolyte is improved and the formed electrode-electrolyte interphase is more uniform and stable,thereby enhancing the electrochemical performance of the cells.As a result,cells assembled with a total of 1 M ternary lithium salts in G2 solvent can operate at high voltage of 4.4 V.The LijjNCM811 cells maintain 80.2%capacity retention after 270 cycles at room temperature,with an average Coulombic efficiency of 99.5%,and exhibit 88.4%capacity retention after 200 cycles at -30℃. 展开更多
关键词 Lithium metal battery ether electrolyte Electric double layer High voltage LOW-TEMPERATURE
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The Development of Zeolite-Based Catalysts for CO_(2) Hydrogenation to Dimethyl Ether
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作者 Zhongyi Xue Wenfu Yan 《Carbon and Hydrogen》 2025年第1期43-51,共9页
The use of fossil fuels significantly contributes to excess CO_(2) emissions.Catalytic hydrogenation of CO_(2) to dimethyl ether(DME)is an effective method for CO_(2) recycling,offering both environmental and economic... The use of fossil fuels significantly contributes to excess CO_(2) emissions.Catalytic hydrogenation of CO_(2) to dimethyl ether(DME)is an effective method for CO_(2) recycling,offering both environmental and economic benefits.Zeolites,known for their efficiency as solid catalysts,are widely utilized in the chemical industries.Bifunctional catalysts based on zeolites have gained attention for their applications in CO_(2) hydrogenation to DME.This review discusses key factors affecting the catalytic performance of zeolites,including topologies,Si/Al ratio,crystal size,and the proximity of metallic species to the zeolite catalysts.Although bifunctional catalytic systems enhance the conversion of CO_(2) to DME,they also lead to high CO selectivity at elevated temperatures,which can limit both DME yield and selectivity.We present recent advancements in the development of bifunctional catalysts for the direct hydrogenation of CO_(2) to DME,providing insights for designing optimized catalysts for tandem reaction systems. 展开更多
关键词 CATALYSTS CO_(2)hydrogenation dimethyl ether ZEOLITE
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Cyclic ethers-based solid electrolyte derived from in situ ring-opening polymerization strategy
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作者 Wubin Du Yong Wu +7 位作者 Hao Cheng Ran Bu Kang Shen Yuanzhong Tan Zhijun Wu Hongge Pan Yifan Wang Yingying Lu 《Green Energy & Environment》 2025年第7期1359-1376,共18页
Although solid-state polymer electrolytes(SPEs)are expected to solve the safety hazards and limited energy density in the energy storage systems,they still encounter an inferior electrode/electrolyte interface when pr... Although solid-state polymer electrolytes(SPEs)are expected to solve the safety hazards and limited energy density in the energy storage systems,they still encounter an inferior electrode/electrolyte interface when prepared in an ex situ manner.Recently,in situ polymerization of SPEs favor high interfacial infiltrability,improved interface contact,and reduced interface resistance,owing to the formation of a"superconformal"interface between electrode and electrolyte.Especially,in situ strategies employing ring-opening polymerization(ROP)are emerging as dazzling stars,further enabling moderate polymerization conditions,controllable molecular structure,and reduced interfacial side reaction.As the main monomers that can be in situ polymerized via the ROP strategy,cyclic ethers have been used to construct the CE-SPEs with many merits,including good battery electrochemical performances and a simple assembly process.Here,as a systematic summarization of the existing reports,this review focuses on the polymerization mechanism of ROP,the design principles of CE-SPEs electrolytes,and the recent application of in situ CE-SPEs.In particular,this review thoroughly discusses the selection of different cyclic monomers,initiators and various modification approaches in in situ fabricating CE-SPEs.Ending with offering future challenges and perspectives,this review envisions shedding light on the profound understanding and scientific guidance for further development of high-performance in situ CE-SPEs. 展开更多
关键词 Cyclic ethers Solid-state polymer electrolytes Ring-opening polymerization In situ polymerization
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Enhanced leaching of ionic rare earth ore facilitated by sodium alcohol ether carboxylate surfactant
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作者 Pengyu Lan Xianping Luo +2 位作者 Yongbing Zhang Peidi Luo Xuekun Tang 《Journal of Rare Earths》 2025年第12期2789-2798,I0007,共11页
Surfactant sodium alcohol ether carboxylate(AEC-9Na)was added to the magnesium sulfate solution in order to enhance the leaching efficiency of ionic rare earth ore,and the mechanism of action for AEC-9Na was elucidate... Surfactant sodium alcohol ether carboxylate(AEC-9Na)was added to the magnesium sulfate solution in order to enhance the leaching efficiency of ionic rare earth ore,and the mechanism of action for AEC-9Na was elucidated.Under optimal conditions,the addition of AEC-9Na with a mass fraction of 0.03% can enhance the leaching rate by 5.2% and reduce the leaching cycle.Kinetic analysis demonstrates that the leaching process follows the model of internal diffusion control.The analysis of the mass transfer process reveals that the addition of AEC-9Na results in a decrease in the height equivalent to a theoretical plate(HETP)and an improvement in mass transfer efficiency.The addition of AEC-9Na can reduce the thickness of the water layer adsorbed on particles during leaching,which in turn reduces hydration and facilitates penetration of the leaching solution into ore body pores.This improves mass transfer concentration differences during leaching,and facilitates desorption of rare earth ions.Periodic density functional theory(DFT)calculations show that the adsorption of AEC-9Na onto the surface of kaolinite(001)enhances the hydrophilicity of the mineral surface and improves its permeability efficiency.Simultaneously,AEC-9Na forms complexes with hydrated rare earth ions on the kaolinite(001)surface,thereby reducing their adsorption strength on clay minerals.This promotes the exchange and desorption process of magnesium ions to hydrated rare earth ions,ultimately enhancing the mass transfer process for leaching rare earth elements. 展开更多
关键词 Ionic rare earth ore Sodium alcohol ether carboxylate SURFACTANT Mass transfer SEEPAGE
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A highly dispersed Pd/CeO_(2)catalyst for boosting C-O bond cleavage of diphenyl ether
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作者 Shiyu Xie Yongjie Xi +9 位作者 Jin Xie Jiaxu Wei Qingyi Liu Yuchen Yang Hailong Lin Yuxin Bai Tingting Wang Pingru Su Zelong Li Yu Tang 《Journal of Rare Earths》 2025年第5期962-970,共9页
Heterogeneous precious metal catalysts are prone to agglomeration during preparation,requiring high usage with consequently high costs.Maximizing the efficiency of precious-metal utilization is of great significance i... Heterogeneous precious metal catalysts are prone to agglomeration during preparation,requiring high usage with consequently high costs.Maximizing the efficiency of precious-metal utilization is of great significance in the design of supported precious metal catalysts.Herein,2,2'-bipyridyl-5,5'-dicarboxylic acid was used as the ligand in constructing the UiO-67-Ce-BPyDC framework with Ce^(4+)coordination.This framework enables precise adsorption and coordination of Pd2+at the nitrogen sites of pyridine,promoting high dispersion of the Pd species at a single site,thereby facilitating controlled palladium loading.This precursor was used to fabricate supported Pd-based catalysts on CeO_(2)(Pd-N/CeO_(2)-P)via pyrolysis.Notably,because the Pd species are homogeneously distributed on CeO_(2)with strong interactions,Pd-N/CeO_(2)-P exhibits remarkable efficiency in cleaving the C-O bonds of diphenyl ether(DPE)to produce cyclohexanol,with a selectivity of 72.1%.The origin of the high selectivity of cyclohexanol is further elucidated using theoretical calculations;that is,DPE undergoes not only hydrogenolysis on Pd-N/CeO_(2)-P,but also hydrolysis to produce more cyclohexanol.This study not only demonstrates a successful strategy for designing highly dispersed metal catalysts,but also underscores the importance of such tailored catalysts in the advancement of sustainable lignin depolymerization technologies. 展开更多
关键词 Metal-organic frameworks Pd-N/CeO_(2)-P catalyst Diphenyl ether C-O bond cleavage Lignin model compound Rare earths
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Catalytic asymmetric inverse-electron-demand Diels-Alder reaction of 2-pyrones with aryl enol ethers
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作者 Fangqing Zhang Yu Wang +3 位作者 Zhenda Tan Yangbin Liu Lijuan Song Xiaoming Feng 《Chinese Chemical Letters》 2025年第7期364-370,共7页
Chiral aryl cyclohex-3-en ether scaffold is widely present in bioactive natural products and drugs.The exploitation of efficient and enantioselective methods for the construction of aryl cyclohex-3-en ether scaffold i... Chiral aryl cyclohex-3-en ether scaffold is widely present in bioactive natural products and drugs.The exploitation of efficient and enantioselective methods for the construction of aryl cyclohex-3-en ether scaffold is significant.Herein we disclose a chiral N,N’-dioxide/Lewis acid complex-catalyzed asymmetric inverse-electron-demand Diels-Alder(IEDDA)reaction using electron-deficient 3-carboalkoxyl-2-pyrones and less electron-enriched aryl enol ethers as reactants.A wide range of non-and 1,2-disubstituted acyclic aryl enol ethers are applicable to deliver diverse chiral bridged bicyclic lactones in high yields and stereoselectivities(up to 96%yield,>20:1 dr,97:3 er).The bridged bicyclic lactone core can be easily converted into chiral aryl cyclohex-3-en ether scaffold.Notably,DFT calculations revealed a stepwise and endo mechanism to explain the high enantioselectivity controlled by the cooperative effect of the steric factors and the dispersion interactions between ligands and enol ethers. 展开更多
关键词 Asymmetric IEDDA reaction Aryl cyclohex-3-en ether scaffold 2-Pyrone Chiral Lewis acid complex Chiral bridged bicyclic lactones
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Highly efficientcleavage of C—O bonds in diphenyl ether over Ni-S_(2)O_(8)^(2-)/ZrO_(2) solid super acid catalysts
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作者 Xiaoyan Zhao Xin Hu +5 位作者 Chuang Zhang Wei Jiang Jingpei Cao Zuxing Huan Yue Wang Changrui Tan 《Chinese Journal of Chemical Engineering》 2025年第10期34-44,共11页
Catalytic aryl ether C—O bonds hydrogenolysis was an important route to convert lignite into high valueadded chemicals.Solid super acid 10%Ni-S_(2)O_(8)^(2-)=ZrO_(2) catalysts were successfully synthesized and evalua... Catalytic aryl ether C—O bonds hydrogenolysis was an important route to convert lignite into high valueadded chemicals.Solid super acid 10%Ni-S_(2)O_(8)^(2-)=ZrO_(2) catalysts were successfully synthesized and evaluated their performance in catalytic hydrolysis of lignite derivatives.The excellent performance of 10%Ni-S_(2)O_(8)^(2-)=ZrO_(2) stems from the synergistic interaction between metallic and acidic sites.Specifically,the acidic sites generated by S_(2)O_(8)^(2-) facilitate the adsorption of O atoms in the substrate,whereas the metal sites optimize the process of hydrogen adsorption and activation and promote the generation of hydrogen radicals,which further enhances the ability to break C—O bonds.Thus,10%Ni-S_(2)O_(8)^(2-)=ZrO_(2) exhibits more significantcatalytic activity compared to 10%Ni-ZrO_(2) prepared from pure ZrO_(2) as a support.Characterization results showed that the 10%Ni-S_(2)O_(8)^(2-)=ZrO_(2) catalyst prepared by sodium borohydride reduction method presented a uniform pore structure,which effectively promoted the dispersion of metal Ni on the catalyst surface.Complete conversion of diphenyl ether(DPE)can be achieved under relatively mild conditions,and excellent hydrogenolysis activity is also demonstrated for other lignite derivatives containing C—O bonds.The possible reaction mechanism of DPE hydrogenolysis in the H_(2)-isopropanol system was investigated.This work represents a significantstep forward in the design of highly efficientsolid super acid catalysts. 展开更多
关键词 Hydrogenation Diphenyl ether C―O cleavage Chemical reaction Ni-S_(2)O_(8)^(2-)=ZrO_(2) Catalyst
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Chinese agarwood petroleum ether extract suppressed gastric cancer progression via up-regulation of DNA damage-induced G_(0)/G_(1)phase arrest and HO-1-mediated ferroptosis
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作者 Lishan Ouyang Xuejiao Wei +8 位作者 Fei Wang HuimingHuang Xinyu Qiu Zhuguo Wang Peng Tan Yufeng Gao Ruoxin Zhang Jun Li Zhongdong Hu 《Chinese Journal of Natural Medicines》 2025年第10期1210-1220,共11页
Gastric cancer(GC)is characterized by high morbidity and mortality rates.Chinese agarwood comprises the resin-containing wood of Aquilaria sinensis(Lour.)Gilg.,traditionally utilized for treating asthma,cardiac ischem... Gastric cancer(GC)is characterized by high morbidity and mortality rates.Chinese agarwood comprises the resin-containing wood of Aquilaria sinensis(Lour.)Gilg.,traditionally utilized for treating asthma,cardiac ischemia,and tumors.However,comprehensive research regarding its anti-GC effects and underlying mechanisms remains limited.In this study,Chinese agarwood petroleum ether extract(CAPEE)demonstrated potent cytotoxicity against human GC cells,with half maximal inhibitory concentration(IC_(50))values for AGS,HGC27,and MGC803 cells of 2.89,2.46,and 2.37μg·mL^(−1),respectively,at 48 h.CAPEE significantly induced apoptosis in these GC cells,with B-cell lymphoma-2(BCL-2)associated X protein(BAX)/BCL-2 antagonist killer 1(BAK)likely mediating CAPEE-induced apoptosis.Furthermore,CAPEE induced G_(0)/G_(1)phase cell cycle arrest in human GC cells via activation of the deoxyribonucleic acid(DNA)damage-p21-cyclin D1/cyclin-dependent kinase 4(CDK4)signaling axis,and increased Fe^(2+),lipid peroxides and reactive oxygen species(ROS)levels,thereby inducing ferroptosis.Ribonucleic acid(RNA)sequencing,real-time quantitative polymerase chain reaction(RT-qPCR),and Western blotting analyses revealed CAPEE-mediated upregulation of heme oxygenase-1(HO-1)in human GC cells.RNA interference studies demonstrated that HO-1 knockdown reduced CAPEE sensitivity and inhibited CAPEE-induced ferroptosis in human GC cells.Additionally,CAPEE administration exhibited robust in vivo anti-GC activity without significant toxicity in nude mice while inhibiting tumor cell growth and promoting apoptosis in tumor tissues.These findings indicate that CAPEE suppresses human GC cell growth through upregulation of the DNA damage-p21-cyclin D1/CDK4 signaling axis and HO-1-mediated ferroptosis,suggesting its potential as a candidate drug for GC treatment. 展开更多
关键词 Chinese agarwood petroleum ether extract(CAPEE) Gastric cancer G_(0)/G_(1)phase arrest Ferroptosis DNA damage-p21-Cyclin D1/CDK4 signaling axis HO-1
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人类ether-à-go-go相关基因在药物诱导性长QT间期综合征发生发展中的作用
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作者 唐闻 廉姜芳 宋勇飞 《实用心电与临床诊疗》 2025年第2期272-277,共6页
人类ether-à-go-go相关基因(human ether-à-go-go related gene,hERG)亚家族H成员2(KCNH2)所编码的快速激活延迟整流钾离子通道,是许多药物心脏毒性的靶标。药物诱导性长QT间期综合征(drug-induced long QT syndrome,diLQTS)... 人类ether-à-go-go相关基因(human ether-à-go-go related gene,hERG)亚家族H成员2(KCNH2)所编码的快速激活延迟整流钾离子通道,是许多药物心脏毒性的靶标。药物诱导性长QT间期综合征(drug-induced long QT syndrome,diLQTS)是由各类抗心律失常药、抗生素、抗组胺药、抗精神病药和血管扩张药等一个或多个脱靶相互作用而诱导的QT间期延长的病理状态。男性校正后的QT间期(QTc)>450 ms、女性QTc>460 ms是diLQTS心电图的临床表征之一。这种获得性长QT间期综合征容易诱发尖端扭转型室性心动过速,继而进展为心室颤动甚至心脏性猝死。本文从化学结构、心电图学、生物学、电生理学和分子生物学这几方面,综述hERG在diLQTS发生发展中的作用。 展开更多
关键词 人类ether-à-go-go相关基因 药物诱导 长QT间期综合征 QT间期
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Review on extraction and separation of valuable metal ions from aqueous solution by crown ether
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作者 Jie Liu Xin Zhang +5 位作者 Xingjie Lu Qianting Li Zhixiao Xue Qiulu Zhang Guizhi Wu Wenxiang Xia 《Chinese Journal of Chemical Engineering》 2025年第9期217-227,共11页
In recent years,with the rapid developme nt of the econo my and society,pollution of valuable metal ions in wastewater has become a major challenge to environmental sustainability.In order to solve the pollution cause... In recent years,with the rapid developme nt of the econo my and society,pollution of valuable metal ions in wastewater has become a major challenge to environmental sustainability.In order to solve the pollution caused by metal ions,researchers have conducted continuous re searches and explored various re mediation methods.Crown ether has attracted great attention because of its ionic radius and cavity size matching well with metal ions,which makes it have the ability to selectively complex metal ions.This unique property enables the directed removal and recovery of metal ions and makes crown ethers increasingly popular in extraction and separation processes.In this paper,the research progress of crown ethers in the extraction and separation of valuable metal ions was reviewed,with emphasis on the principles,extraction systems and the key factors affecting the extraction process.This study can provide some technical support for the application of separation and extraction of valuable metal ions by crown ether. 展开更多
关键词 Review on extraction and separation of valuable metal ions from aqueous solution by crown ether
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沉默Ether à go-go 1基因调控VEGF/PI3K/AKT抑制骨肉瘤增殖和血管生成的研究 被引量:9
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作者 吴进 刘庆军 +3 位作者 曾文容 吴采荣 戴立林 陈志达 《肿瘤预防与治疗》 2016年第4期193-198,共6页
目的:检测沉默Ether à go-go 1(Eag1)基因对骨肉瘤增殖和血管生成的影响及其可能的调控机制。方法:构建抑制Eag1表达的短发卡RNA(short hair RNA,shRNA)重组腺病毒载体Ad5-Eag1-shRNA并感染骨肉瘤细胞株。采用实时定量聚合酶链反应... 目的:检测沉默Ether à go-go 1(Eag1)基因对骨肉瘤增殖和血管生成的影响及其可能的调控机制。方法:构建抑制Eag1表达的短发卡RNA(short hair RNA,shRNA)重组腺病毒载体Ad5-Eag1-shRNA并感染骨肉瘤细胞株。采用实时定量聚合酶链反应(real-time polymerase chain reaction,Real-time PCR)和蛋白印迹技术(Western blot analysis,WB)检测Ad5-Eag1-shRNA的感染效能。采用CCK-8法和裸鼠成瘤实验检测感染前后骨肉瘤细胞增殖和裸鼠骨肉瘤体积的变化。采用免疫组化技术和WB技术分别检测感染前后裸鼠肿瘤组织中微血管密度(microvessel density,MVD)和血管内皮生长因子(vascular endothelial growth factor,VEGF)表达的变化。采用WB技术检测感染前后骨肉瘤细胞中VEGF、磷脂酰肌醇3-激酶(phosphoinositide 3-kinase,PI3K)和蛋白激酶B(protein kinase B,AKT)的表达变化。结果:构建的重组腺病毒载体Ad5-Eag1-shRNA具有良好的感染效能。感染Ad5-Eag1-shRNA可沉默骨肉瘤中Eag1的表达并能有效地抑制骨肉瘤细胞增殖和裸鼠骨肉瘤生长(均P<0.001),同时下调裸鼠骨肉瘤组织中MVD密度和VEGF的表达(均P<0.001)。感染Ad5-Eag1-shRNA可下调骨肉瘤细胞中VEGF的表达(P<0.05)并抑制PI3K和AKT的磷酸化(均P<0.001)。结论:沉默Eag1可能通过调控VEGF/PI3K/AKT信号通路抑制骨肉瘤增殖和血管生成。 展开更多
关键词 ether à go-go 1基因 血管内皮生长因子 骨肉瘤 细胞增殖 血管生成
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Synthesis of Methyl Acetate by Dimethyl Ether Carbonylation over Cu/HMOR: Effect of Catalyst Preparation Method 被引量:4
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作者 张雪 李宇萍 +5 位作者 仇松柏 王铁军 定明月 张琦 马隆龙 于玉肖 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第1期77-82,I0004,共7页
Dimethyl ether carbonylation to methyl acetate was comparatively investigated over mor- denite supported copper (Cu/HMOR) catalysts prepared by different methods including evaporation, urea hydrolysis, incipient wet... Dimethyl ether carbonylation to methyl acetate was comparatively investigated over mor- denite supported copper (Cu/HMOR) catalysts prepared by different methods including evaporation, urea hydrolysis, incipient wetness impregnation and ion-exchange. The results showed that Cu/HMOR prepared via iron-exchange method exhibited the highest catalytic activity due to the synergistic effect of active-site metal and acidic molecular sieve support. Conversion of 95.3% and methyl acetate selectivity of 94.9% were achieved under conditions of 210℃, 1.5 MPa, and GSHV of 4883 h-1. The catalysts were characterized by nitrogen absorption, X-ray diffraction, NH3 temperature program desorption, and CO temperature program desorption techniques. It was found that Cu/HMOR prepared by ion-exchange method possessed high surface area, moderate strong acid centers, and CO adsorption centers, which improved catalytic performance for the reaction of CO insertion to dimethyl ether. 展开更多
关键词 Biomass energy Methyl acetate Dimethyl ether CARBONYLATION HMOR cat-alyst
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