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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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Interfacial engineering through lead binding using crown ethers in perovskite solar cells 被引量:1
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作者 Sun-Ju Kim YeonJu Kim +8 位作者 Ramesh Kumar Chitumalla Gayoung Ham Thanh-Danh Nguyen Joonkyung Jang Hyojung Cha Jovana Milić Jun-Ho Yum Kevin Sivula Ji-Youn Seo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期263-270,共8页
In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative solutions.This study pioneers an ... In the domain of perovskite solar cells(PSCs),the imperative to reconcile impressive photovoltaic performance with lead-related issue and environmental stability has driven innovative solutions.This study pioneers an approach that not only rectifies lead leakage but also places paramount importance on the attainment of rigorous interfacial passivation.Crown ethers,notably benzo-18-crown-6-ether(B18C6),were strategically integrated at the perovskite-hole transport material interface.Crown ethers exhibit a dual role:efficiently sequestering and immobilizing Pb^(2+)ions through host-vip complexation and simultaneously establishing a robust interfacial passivation layer.Selected crown ether candidates,guided by density functional theory(DFT)calculations,demonstrated proficiency in binding Pb2+ions and optimizing interfacial energetics.Photovoltaic devices incorporating these materials achieved exceptional power conversion efficiency(PCE),notably 21.7%for B18C6,underscoring their efficacy in lead binding and interfacial passivation.Analytical techniques,including time-of-flight secondary ion mass spectrometry(ToF-SIMS),ultraviolet photoelectron spectroscopy(UPS),time-resolved photoluminescence(TRPL),and transient absorption spectroscopy(TAS),unequivocally affirmed Pb^(2+)ion capture and suppression of non-radiative recombination.Notably,these PSCs maintained efficiency even after enduring 300 h of exposure to 85%relative humidity.This research underscores the transformative potential of crown ethers,simultaneously addressing lead binding and stringent interfacial passivation for sustainable PSCs poised to commercialize and advance renewable energy applications. 展开更多
关键词 Perovskite solar cells Interfacial passivation crown ether materials Stability
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Crown aldoxime ethers:Their synthesis,structure,acid-catalyzed/photo-induced isomerization and adjustable vip binding
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作者 Yulin Mao Jingyu Ma +3 位作者 Jiecheng Ji Yuliang Wang Wanhua Wu Cheng Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第11期318-322,共5页
A series of novel crown aldoxime ethers were synthesized,demonstrating notable thermal and hydrolysis stability.The showcased acid-catalyzed and photo-induced cis/trans isomerization,which enables orthogonal control o... A series of novel crown aldoxime ethers were synthesized,demonstrating notable thermal and hydrolysis stability.The showcased acid-catalyzed and photo-induced cis/trans isomerization,which enables orthogonal control over both vip complexation and the chiroptical effects of these crown aldoxime ethers,manifesting a regulation of complexation through isomerization at binding heteroatoms. 展开更多
关键词 crown aldoxime ether Cis/trans isomerization PHOTOISOMERIZATION Chiroptical induction Orthogonal control
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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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An optimization framework for hot-rolled strip crown control based on model-driven digital twin 被引量:1
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作者 Fen-jia Wang Chao Liu +6 位作者 An-rui He Yong Song Jian Shao Chi-huan Yao Yi Qiang Hong-yan Liu Bo Ma 《Journal of Iron and Steel Research International》 2025年第7期1920-1939,共20页
Accurate crown control is paramount for ensuring the quality of hot-rolled strip products.Given the multitude of influencing parameters and the intricate coupling and genetic relationships among them,the conventional ... Accurate crown control is paramount for ensuring the quality of hot-rolled strip products.Given the multitude of influencing parameters and the intricate coupling and genetic relationships among them,the conventional crown control method is no longer sufficient to meet the precision requirements of schedule-free rolling.To address this limitation,an optimization framework for hot-rolled strip crown control was developed based on model-driven digital twin(MDDT).This framework enhances the strip crown control precision by facilitating collaborative operations among physical entities,virtual models,and functional application layers.In virtual modeling,a data-driven approach that integrates the extreme gradient boosting and the improved Harris hawk optimization algorithm was firstly proposed to fit the relationship between key process parameters and strip crown,and a global-local collaborative training strategy was proposed to enhance the model adaptability to diverse working conditions.Subsequently,the influence of crucial process factors on the virtual model was examined through model responses.Furthermore,a novel optimization mode for crown control based on MDDT was established by aligning and reconstructing both the physical and virtual models,thereby enhancing the crown control precision.Finally,data trials were conducted to validate the effectiveness of the proposed framework.The results indicated that the proposed method exhibited satisfactory performance and could be effectively utilized to improve the crown control precision. 展开更多
关键词 Hot-rolled strip crown control Machine learning Digital twin Extreme gradient boosting
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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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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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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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Corrigendum to“Crown saturation and intrasexual dominance:Evidence of a negatively correlated handicap in male Saffron Finches”[Avian Res.16(2025)100241]
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作者 Camilo Ernesto Espinosa James Montoya Lerma +1 位作者 Hector Fabio Rivera-Gutierrez Lorena Cruz-Bernate 《Avian Research》 2025年第2期301-301,共1页
The authors regret that the declaration of Acknowledgement as below is missing in the paper:AcknowledgementWe are grateful to the Department of Biology and Postgraduate Sciences-Biology of the Universidad del Valle,Ca... The authors regret that the declaration of Acknowledgement as below is missing in the paper:AcknowledgementWe are grateful to the Department of Biology and Postgraduate Sciences-Biology of the Universidad del Valle,Cali-Colombia for their support of the project;to Wilmar Torres MSc.for his statistical advice;to the biologist Helen Burnham MSc.for the translation of the document;to Isabel Castro and all the members of the Ornithology and Animal Behaviour Laboratory-OYCA of Universidad del Valle for their invaluable support in the field.We sincerely thank the anonymous re-viewers for their invaluable feedback and contributions to our manuscript. 展开更多
关键词 intrasexual dominance HANDICAP declaration acknowledgement crown saturation saffron finches ACKNOWLEDGEMENT
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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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Nonlinear multilevel seemingly unrelated height-diameter and crown length mixed-effects models for the southern Transylvanian forests,Romania
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作者 Albert Ciceu Stefan Leca +1 位作者 Ovidiu Badea Lauri Mehtatalo 《Forest Ecosystems》 2025年第4期630-641,共12页
In this study,we used an extensive sampling network established in central Romania to develop tree height and crown length models.Our analysis included more than 18,000 tree measurements from five different species.In... In this study,we used an extensive sampling network established in central Romania to develop tree height and crown length models.Our analysis included more than 18,000 tree measurements from five different species.Instead of building univariate models for each response variable,we employed a multivariate approach using seemingly unrelated mixed-effects models.These models incorporated variables related to species mixture,tree and stand size,competition,and stand structure.With the inclusion of additional variables in the multivariate seemingly unrelated mixed-effects models,the accuracy of the height prediction models improved by over 10% for all species,whereas the improvement in the crown length models was considerably smaller.Our findings indicate that trees in mixed stands tend to have shorter heights but longer crowns than those in pure stands.We also observed that trees in homogeneous stand structures have shorter crown lengths than those in heterogeneous stands.By employing a multivariate mixed-effects modelling framework,we were able to perform cross-model random-effect predictions,leading to a significant increase in accuracy when both responses were used to calibrate the model.In contrast,the improvement in accuracy was marginal when only height was used for calibration.We demonstrate how multivariate mixed-effects models can be effectively used to develop multi-response allometric models that can be easily calibrated with a limited number of observations while simultaneously achieving better-aligned projections. 展开更多
关键词 Multivariate model Cross-model calibration crown allometry Multilevel model Mixed stands Heterogeneous stand structure
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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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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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Exciton dynamics and random lasing in surface-passivated CdSe/CdSeS core/crown nanoplatelets
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作者 Huan Liu Puning Wang Rui Chen 《Chinese Physics B》 2025年第9期179-184,共6页
CdSe nanoplatelets(NPLs)are promising candidates for on-chip light sources,yet their performance is hindered by surface defects and inefficient optical gain.Herein,we demonstrate that CdSeS crown passivation significa... CdSe nanoplatelets(NPLs)are promising candidates for on-chip light sources,yet their performance is hindered by surface defects and inefficient optical gain.Herein,we demonstrate that CdSeS crown passivation significantly enhances the photophysical property of CdSe NPLs.Laser spectroscopy techniques reveal suppressed electronic and hole trapping at lateral surfaces,leading to a 4.2-fold increase in photoluminescence quantum yield and a shortened emission lifetime from13.5 to 4.8 ns.In addition,amplified spontaneous emission is achieved under nanosecond pulse pumping,with thresholds of0.75 to 0.16 mJ/cm^(2)for CdSe and CdSe/CdSeS NPLs,respectively.By integrating CdSe/CdSeS NPLs with high-refractiveindex SiO2scatters,coherent random lasing is realized at a threshold of 0.21 mJ/cm^(2).These findings highlight the critical role of lateral surface passivation in optimizing optical gain and pave the way for low-cost,multifunctional nanophotonic devices. 展开更多
关键词 CdSe nanoplatelets core/crown heterostructures surface passivation amplified spontaneous emission random lasing
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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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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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Preparation of Copolymer of Salen-crown Ether Complexes and its Catalytic Activation for Molecular Oxygen 被引量:2
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作者 Rong Min WANG Xiao Dong LI Yu Feng HE 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第2期265-268,共4页
A new stable salen Schiff base cobalt and crown ether sodium complex (SalCo-NaB18C6) was prepared through copolymerization. This copolymer complex was applied to catalytic oxidation of hydrocarbon compound with mole... A new stable salen Schiff base cobalt and crown ether sodium complex (SalCo-NaB18C6) was prepared through copolymerization. This copolymer complex was applied to catalytic oxidation of hydrocarbon compound with molecular oxygen without reductant, which was shown the higher activity and selectivity for ketone, and reused effectively. 展开更多
关键词 Copolymeric complexes CYCLOHEXENE CATALYSIS salen Schiff base crown ether.
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Cross-Linked Crown Ether-SE-54 as Stationary Phase for Open-Tubular Column Gas Chromatography
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作者 朱荣萍 傅若农 +4 位作者 葛继龙 王宏菊 朱济亚 黄载福 张斌 《Journal of Beijing Institute of Technology》 EI CAS 1992年第2期87-93,共7页
The cross-linking of crown ether-SE-54 in fused-silica capillary columns were initiated by dicumyl peroxide(DCUP),azo-bis-isobutyronitrile (AIBN)and ozone(O_3).Parameters of evaluation such as polarity,selectivity, ph... The cross-linking of crown ether-SE-54 in fused-silica capillary columns were initiated by dicumyl peroxide(DCUP),azo-bis-isobutyronitrile (AIBN)and ozone(O_3).Parameters of evaluation such as polarity,selectivity, phase transition temperature and thermal stability were studied and compared with those of poly(crown ether)stationary phase. 展开更多
关键词 gas chromatography crosslinking/capillary gas chromatography crown ether poly(crown ether)
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