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Eco-friendly and facile nanomanufacturing of amorphous Co-Ce-Fe trimetallic molybdates composites for accelerated anodic oxygen evolution in alkaline water electrolysis: Evaluation of active sites performance
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作者 Jiejie Feng Liling Wei +1 位作者 Huayi Li Jianquan Shen 《Green Energy & Environment》 2025年第5期1027-1038,共12页
Currently,endeavors to scale up the production of amorphous catalysts are still impeded by intricate synthesis conditions.Here,we have prepared a series of metal-based molybdate via one-step coprecipitation method.Aft... Currently,endeavors to scale up the production of amorphous catalysts are still impeded by intricate synthesis conditions.Here,we have prepared a series of metal-based molybdate via one-step coprecipitation method.After ingredient optimization,amorphous Co_(2)CeFe_(2)-MoO_(4) was identified as exhibiting the highest intrinsic activity among its counterparts.Modulation of electron structure enables Co_(2)CeFe_(2)-MoO_(4) to balance the adsorption behavior towards reactive intermediates.Ultimately,the obtained Co_(2)CeFe_(2)-MoO_(4) molybdate demonstrated a captivating OER performance,showcasing a low overpotential of 230 mV at 10 mA cm^(-2).Moreover,the alkaline electrolyzer employing the Co_(2)CeFe_(2)-MoO_(4) anode exhibited a low cell voltage of 1.50 V for water splitting and underwent an acceptable attenuation of 4.99% after 165 h of continuous operation,demonstrating its favorable catalytic activity and durability.This work provides a facile and eco-friendly synthesis pathway for crafting cost-effective and durable earth-abundant OER electrocatalysts tailored for water splitting to produce clean hydrogen. 展开更多
关键词 Oxygen evolution reaction Coprecipitation synthesis Ternary metal molybdates High intrinsic activity Water splitting
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Enhancing hydrogen storage performance of magnesium hydride with Ni cluster-loaded MXene-Nb_(2)CT_(x)(T_(x)=F,O)
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作者 Hui Liang Peng-Fei Zhang +1 位作者 Yuan Wang Jie Zheng 《Rare Metals》 2025年第7期4712-4723,共12页
The robust Mg-H bonds present in magnesium hydride(MgH_(2))hinder the dissociation of hydrogen molecules on MgH_(2),leading to suboptimal thermo dynamic and kinetic properties.Transition metals such as nickel(Ni)and N... The robust Mg-H bonds present in magnesium hydride(MgH_(2))hinder the dissociation of hydrogen molecules on MgH_(2),leading to suboptimal thermo dynamic and kinetic properties.Transition metals such as nickel(Ni)and Nb exhibit superior hydrogen absorption energies as compared to Mg.By integrating two-dimensional Nb_(n)C_(n-1)T_(x)-MXene(with a large specific surface area and strong hydrogen absorption capacity provided by Nb)with Ni clusters,we developed an effective catalyst for hydrogen adsorption in MgH_(2).This study focused on the synthesis of an efficient MXene-Nb_(2)CT_(x)composite containing nano Ni cluster to enhance the hydrogenation and dehydrogenation processes of the Mg/MgH_(2)system.The Txend groups(-F,-O)were found to interact with Ni to create Ni-F or Ni-O bonds,which subsequently engage with adjacent Ni atoms to form Ni-Ni bonds.This interaction facilitates the loading of Ni clusters onto Nb_(2)CT_(x)and mitigates the inhibitory effects of-F or-O on hydrogen adsorption and desorption in the Mg-based system.Consequently,Nb_(2)C and Ni operate synergistic ally to enhance hydrogen dissociation and weaken Mg-H bonds.Theoretical simulations revealed that the inclusion of the Nb_(2)C/Ni catalyst in an elongation of Mg-H bonds enhancehydrogen dissociation and weaken Mg-H bonds.Theoretical simulations revealed that the inclusion of the Nb_(2)C/Ni catalyst in an elongation of Mg-H bonds facilitate hydrogen molecule dissociation on the Nb_(2)C/Ni composite.Hydrogen storage performance assesments demonstrated that the Nb_(2)C/Ni catalyst efficiently catalyzed hydrogen absorption and desorption;specifically,the hydrogenation/dehydrogenation capacity of Nb_(2)C/Ni@MgH_(2)reachedca.5.0 wt%at 100℃,while at 200℃,the capacities for hydrogenation and dehydrogenation reached 7.0 wt%and6.0 wt%,respectively,within 6 min. 展开更多
关键词 Nb_(2)CT_(x)-MXene Ni clusters onto Nb_(2)CT_(x) Catalyzed hydrogen absorption and desorption Mg-H bonds Hydrogen molecule dissociation
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Experimental Lifetime Measurements of C_(2)in the High-lying(2-4)^(3)Δ_(g) States
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作者 Di Li Liying Ma +2 位作者 Pan Jiang Min Cheng Hong Gao 《Chinese Journal of Chemical Physics》 2025年第5期565-574,I0002-I0004,I0147,共14页
The dicarbon(C_(2))molecule is an important molecular species observed in many carbon-containing gaseous environments.The spectroscopic and dissociative studies of C_(2)have attracted great attention for a long time f... The dicarbon(C_(2))molecule is an important molecular species observed in many carbon-containing gaseous environments.The spectroscopic and dissociative studies of C_(2)have attracted great attention for a long time for understanding its electronic characters as well as the evolution and cycling of carbon in the universe.In this study,the lifetimes of C_(2)populated at the three high-lying electronic states of(2-4)^(3)Δ_(g) in the vacuum ultraviolet(VUV)region have been experimentally measured using a time-of-flight mass spectrometer and the VUV-pump-UV-probe photoionization scheme.The measurements showed that all the rovibronic levels in the 2(g)^(3)Δ_(g) state exhibit shorter lifetimes than the dynamical limit of the experimental method,consistent with the theoretically predicted radiative lifetimes.Dependence of the lifetime on the vibrational level was observed in the 3^(3)Δ_(g) state,and a marginal rotational dependence was noticed in the vʹ=1 vibrational level.For the 4^(3)Δ_(g) state,the rotationally resolved lifetimes in the vʹ=1 vibrational level were found to be slightly longer than those in the vʹ=0 and 2 vibrational levels.Such a complicated dependence of the lifetime on the rovibronic level makes further experimental and theoretical investigations highly desired for understanding the dynamics in the high-lying excited states of C_(2). 展开更多
关键词 Dicarbon LIFETIME PUMP-PROBE DISSOCIATION
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Unraveling post-growth mechanisms of monolayer CsPbBr3 nanocubes:Laser-enhanced transformations and cathodoluminescence-electron microscopy correlations
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作者 Mingxing Li Xiaoge Wang +5 位作者 Xiaofan Cao Zhiqun He Chunjun Liang Mingxing Chen Jing Ju Fangtian You 《Journal of Energy Chemistry》 2025年第1期146-156,共11页
Lead-halide perovskite nanoparticles(LHP NPs) are highly promising materials for next-generation displays and solid-state lighting due to their exceptional optical properties. However, their inherent instability prese... Lead-halide perovskite nanoparticles(LHP NPs) are highly promising materials for next-generation displays and solid-state lighting due to their exceptional optical properties. However, their inherent instability presents a significant challenge. Recent advances have demonstrated that optoelectronic devices based on monolayer nanoparticle films exhibit both high luminescence efficiency and long-term stability.Our research demonstrates that mobility limitations and anisotropic alignments in CsPbBr3nanocube monolayer films are key to their stabilization, hindering spontaneous growth through face-to-face fusion and resulting in the formation of connecting necks in a diagonal direction. Introducing laser irradiation confirmed this by significantly accelerating nanocubes growth, increasing mobility, and enhancing local structural ordering, leading to larger and more regularly shaped nanosheets. Fourier transform infrared spectroscopy and energy dispersive spectroscopy line-scan analyses indicated that laser irradiation did not disrupt the ligand structure. Transmission electron microscopy and correlative cathodoluminescence electron microscopy revealed the effects of post-growth and heterogeneous structures, including enhanced luminescence and inhomogeneous intensity in the nanosheets. These findings deepen the understanding of the post-growth mechanism of monolayer nanoparticles and the structure-emission correlation and highlight the unique role of laser irradiation in directing the formation of well-defined and regular nanostructures. 展开更多
关键词 CsPbBr3 nanocubes Post-growth mechanism Heterogeneous structure Single-particle spectroscopy Laser irradiation
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Geometric Structures and Electronic Properties of Co_(2)Ge_(10)^(-/0):Anion Photoelectron Spectroscopy and Quantum Chemistry Calculations
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作者 Wen-Shuai Dai Xi-Long Li +2 位作者 Hong-Guang Xu Xi-Ling Xu Wei-Jun Zheng 《Chinese Journal of Chemical Physics》 2025年第5期683-690,I0109-I0119,I0149,共20页
The structure and electronic properties of Co_(2)Ge_(10)^(-)anion and its neutral counterpart were investigated by anion photoelectron spectroscopy and theoretical calculations.The experimental vertical detachment ene... The structure and electronic properties of Co_(2)Ge_(10)^(-)anion and its neutral counterpart were investigated by anion photoelectron spectroscopy and theoretical calculations.The experimental vertical detachment energy of Co_(2)Ge_(10)^(-)was measured to be 2.86±0.08 eV.The lowest-energy isomer of Co_(2)Ge_(10)^(-)is in a doublet state and has a cage-like structure with Cs symmetry,which can be constructed by a tetragonal bipyramid on top of a pentagonal bipyramid and these two bipyramid structures share a common Co atom.The most stable structure of neutral Co_(2)Ge_(10)resembles its anionic counterpart and it is in a triplet state.The natural population analysis showed that the inner Co atom of both the anionic and neutral Co_(2)Ge_(10)acquires negative charge from the neighboring Ge atoms.The outer Co atom has a larger spin moment than the inner Co atom,indicating that the magnetic moments of Co_(2)Ge_(10)^(-/0)are mainly contributed by the outer Co atom.Analyses of the density of states and molecular orbitals indicated that there are a few highly delocalized molecular orbitals in Co_(2)Ge_(10)^(-),which are mainly contributed by Ge 4s atomic orbitals. 展开更多
关键词 Semiconductor clusters PHOTOELECTRON Density functional theory Geometric structures
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Janus-type BN-embedded perylene diimides via a“shuffling”strategy:Regioselective functionalizable building block towards high-performance n-type organic semiconductors
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作者 Kexiang Zhao Zongrui Wang +4 位作者 Qi-Yuan Wan Jing-Cai Zeng Li Ding Jie-Yu Wang Jian Pei 《Chinese Chemical Letters》 2025年第6期417-422,共6页
Regioselevtive functionalization of perylene diimides(PDIs)at bay area often requires multistep synthesis and strenuous recrystallization.Direct bromination of perylene diimides only afford the 1,6 and 1,7-regioisomer... Regioselevtive functionalization of perylene diimides(PDIs)at bay area often requires multistep synthesis and strenuous recrystallization.Direct bromination of perylene diimides only afford the 1,6 and 1,7-regioisomers.More importantly,the 1,6-dibromo regioisomers could only be separated by preparative HPLC.Herein,we report a promising strategy for constructing Janus backbone of BN-doped perylene diimide derivatives.This Janus-type configuration results in the unique regioselective functionalization of BN-JPDIs,which yields exclusively the 1,6-regioisomers.Further investigation shows that the Janus-type configuration leads to a net dipole moment of 1.94 D and intramolecular charge transfer,which causes substantial changes on the optoelectronic properties.Moreover,the single crystal organic field-effect transistors based on BN-JPDIs exhibit electron mobilities up to 0.57 cm^(2)V^(-1)s^(-1),showcasing their potential as versatile building block towards high-performance n-type organic semiconductors. 展开更多
关键词 BN heterocycles Perylene diimides Regioselective functionalization Intramolecular charge transfer N-type organic semiconductors
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Promoting stability of sub-3 nm In_(2)S_(3)nanoparticles via sulfur anchoring for CO_(2)electroreduction to formate
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作者 Fanrong Chen Jiaju Fu +4 位作者 Liang Ding Xiaoying Lu Zhe Jiang Xiaoling Zhang Jin-Song Hu 《Chinese Journal of Catalysis》 2025年第4期138-145,共8页
The p-block metal(In,Sn,Bi,etc.)-based electrocatalysts have exhibited excellent activity in the electrocatalytic CO_(2)reduction(ECR)to formate.However,the rapid decrease in catalytic activity caused by catalyst reco... The p-block metal(In,Sn,Bi,etc.)-based electrocatalysts have exhibited excellent activity in the electrocatalytic CO_(2)reduction(ECR)to formate.However,the rapid decrease in catalytic activity caused by catalyst reconstruction and agglomeration under ECR conditions significantly restricts their practical applications.Herein,we developed a sulfur anchoring strategy to stabilize the high-density sub-3 nm In_(2)S_(3)nanoparticles on sulfur-doped porous carbon substrates(i-In_(2)S_(3)/S-C)for formate production.Systematic characterizations evidenced that the as-prepared catalyst exhibited a strong metal sulfide-support interaction(MSSI),which effectively regulated the electronic states of In_(2)S_(3),achieving a high formate Faradaic efficiency of 91%at−0.95 V vs.RHE.More importantly,the sulfur anchoring effectively immobilized the sub-3 nm In_(2)S_(3)nanoparticles to prevent them from agglomeration.It enabled the catalysts to exhibit much higher durability than the In_(2)S_(3)samples without sulfur anchoring,demonstrating that the strong MSSI and fast charge transfer on the catalytic interface could significantly promote the structural stability of In_(2)S_(3)catalysts.These results provide a viable approach for developing efficient and stable electrocatalysts for CO_(2)reduction. 展开更多
关键词 Electrochemical CO_(2)reduction Strong metal sulfide-support interaction In_(2)S_(3)nanoparticles STABILITY FORMATE
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The Influence of Heterogeneous Processes on the Physicochemical Properties of Atmospheric Aerosols
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作者 Maofa GE Shengrui TONG +7 位作者 Lin DU Lingyan WU Ting LEI Kun LI Minglan XU Narcisse T.TSONA Wenqian ZHANG Hailiang ZHANG 《Advances in Atmospheric Sciences》 2025年第4期623-640,共18页
With the rapid development of the world economy,complex air pollution has increasingly become a serious threat;for example,with haze events occurring frequently in various regions of the globe.Recent evidence has indi... With the rapid development of the world economy,complex air pollution has increasingly become a serious threat;for example,with haze events occurring frequently in various regions of the globe.Recent evidence has indicated that secondary aerosols play an important role in haze formation,and that heterogeneous processes are among the main forces driving their explosive growth.In this regard,this paper reviews recent advances in the understanding of the impact of heterogeneous processes on haze chemistry,including the impact on NO_(2)chemistry,marine aerosols,and the hygroscopicity and optical properties of atmospheric aerosols.It is distinguished from past reviews on this topic by focusing mainly on new insights from the past five years.We summarize the main findings of the impacts of heterogeneous processes on NO_(2)chemistry,marine aerosols,and the physicochemical properties of atmospheric aerosols,and propose several future research directions. 展开更多
关键词 heterogeneous chemistry ATMOSPHERE AEROSOLS physicochemical properties
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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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Dicyandiamide-Driven Tailoring of the n-Value Distribution and Interface Dynamics for High-Performance ACI 2D Perovskite Solar Cells
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作者 Ge Chen Yunlong Gan +8 位作者 Shiheng Wang Xueru Liu Jing Yang Sihui Peng Yingjie Zhao Pengwei Li Asliddin Komilov Yanlin Song Yiqiang Zhang 《Nano-Micro Letters》 2025年第12期257-270,共14页
Organic-inorganic hybrid perovskite solar cells achieve remarkable efficiencies(>26%)yet face stability challenges.Quasi-2D alternating-cation-interlayer perovskites offer enhanced stability through hydrophobic spa... Organic-inorganic hybrid perovskite solar cells achieve remarkable efficiencies(>26%)yet face stability challenges.Quasi-2D alternating-cation-interlayer perovskites offer enhanced stability through hydrophobic spacer cations but suffer from vertical phase segregation and buried interface defects.Herein,we introduce dicyanodiamide(DCD)to simultaneously address these dual limitations in GA(MA)_(n)Pb_(n)I_(3n+1)perovskites.The guanidine group in DCD passivates undercoordinated Pb^(2+)and MA^(+)vacancies at the perovskite/TiO_(2)interface,while cyano groups eliminate oxygen vacancies in TiO_(2)via Ti^(4+)-CN coordination,reducing interfacial trap density by 73%with respect to the control sample.In addition,DCD regulates crystallization kinetics,suppressing low-n-phase aggregation and promoting vertical alignment of high-n phases,which benefit for carrier transport.This dual-functional modification enhances charge transport and stabilizes energy-level alignment.The optimized devices achieve a record power conversion efficiency of 21.54%(vs.19.05%control)and retain 94%initial efficiency after 1200 h,outperforming unmodified counterparts(84%retention).Combining defect passivation with phase homogenization,this work establishes a molecular bridge strategy to decouple stability-efficiency trade-offs in low-dimensional perovskites,providing a universal framework for interface engineering in high-performance optoelectronics. 展开更多
关键词 Alternating-cation-interlayer 2D perovskite solar cell Phase modulation Buried interface Interface dynamics
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2D hexagonal tessellations sustained by Br…Br/H contacts:From regular to semiregular to k-uniform tilings
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作者 Junjie Duan Dan Chen +3 位作者 Long Chen Shuying Li Ting Chen Dong Wang 《Chinese Chemical Letters》 2025年第3期458-462,共5页
Achieving seamless tiling through the self-assembly of organic species has long fascinated scientists for its potential applications across various fields.However,constructing periodic nanostructures with high-order t... Achieving seamless tiling through the self-assembly of organic species has long fascinated scientists for its potential applications across various fields.However,constructing periodic nanostructures with high-order tessellation remains challenging,particularly in achieving precise control at the supramolecular level.In this study,we present the successful creation of multiple seamless 2D tessellations on Au(111)surface using versatile hexagonal tiles derived from a singular molecular unit,namely 2,6,10-tribromotricycloquinazoline.Through scanning tunneling microscopy imaging,seven distinct 2D tessellations,ranging from regular to semiregular to k-uniform tilings,are unveiled at the molecular level.Density functional theory calculations provide a theoretical basis for the formation of these complex 2D tessellation,highlighting the important role of the variability of Br···Br/H contacts in facilitating complex seamless 2D tessellations on surface.This work opens avenues for exploring possibilities in constructing intricate tiling patterns with diverse applications. 展开更多
关键词 2D tessellation Molecular self-assembly Scanning tunneling microscopy Noncovalent interactions
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Suppression of light-induced phase segregation in all-inorganic wide-bandgap perovskite solar cells via molecular interaction design
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作者 Jing Yang Yunlong Gan +5 位作者 Mengqi Han Shiheng Wang Pengwei Li Yiqiang Zhang Gang Li Yanlin Song 《Journal of Energy Chemistry》 2025年第9期550-557,I0015,共9页
Wide-bandgap mixed-halide perovskites,particularly CsPbIBr_(2),hold great promise for multi-junction solar cells due to their well-matched bandgap and all-inorganic material system.However,their inherent susceptibilit... Wide-bandgap mixed-halide perovskites,particularly CsPbIBr_(2),hold great promise for multi-junction solar cells due to their well-matched bandgap and all-inorganic material system.However,their inherent susceptibility to light-induced phase segregation(LIPS)limits efficiency and stability.In this work,we investigate the effect of three organic additives-4-cyclopentene-1,3-dione(CPD),maleimide(HPD),and 3,4-dibromo-1H-pyrrole-2,5(2H,5H)-dione(BrPD)-on LIPS in wide-bandgap CsPbIBr_(2)perovskite films.The additives form various chemical interactions,including coordination bonds,hydrogen bonds,and ionic bonds,with I^(-)and undercoordinated Pb^(2+)ions,among which BrPD has the strongest interaction.This interaction regulates crystallization and improves film morphology.The BrPD-modified films have the largest grain size and the highest light stability,suppressing LIPS,enhancing carrier transfer,and improving device performance.BrPD-modified CsPbIBr_(2)-based solar cells achieve a power conversion efficiency(PCE)of 11.34%,outperforming the control(8.96%)and other additives.Moreover,BrPDmodified devices show excellent stability,retaining 94%of their initial PCE after 60 min of continuous light exposure.This work highlights the potential of strategically selected organic additives to enhance the stability and performance of perovskite solar cells,offering valuable insights for the design of high-efficiency and long-lasting perovskite-based optoelectronic devices. 展开更多
关键词 Wide-bandgap perovskite Light-induced phase segregation PHOTOSTABILITY CsPbIBr_(2)all-inorganic perovskite Molecular interactions
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Malignant ascites enhance γδT cell cytotoxicity toward ovarian cancer via chemokine-mediated recruitment
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作者 Zhanqun Yang Ying Liu +8 位作者 Mengzhu Zheng Hui Li Ruoyao Cui Pan Wang Tianhui He Hongyan Guo Yinglin Zhou Jian Lin Long Chen 《Cancer Biology & Medicine》 2025年第6期639-643,共5页
Ovarian cancer remains a leading cause of gynecological cancer mortality1,and patients with advanced stage ovarian cancer frequently develop malignant ascites that foster immunosuppressive microenvironments and therap... Ovarian cancer remains a leading cause of gynecological cancer mortality1,and patients with advanced stage ovarian cancer frequently develop malignant ascites that foster immunosuppressive microenvironments and therapeutic resistance2,3.Although ascites have traditionally been considered detrimental,we report a paradoxical role in which they enhance the cytotoxicity ofγδT cells—a unique T cell subset that can be allogenically transferred for cancer treatment4,5—toward ovarian cancer. 展开更多
关键词 therapeutic resistance malignant ascites ovarian cancer enhance cytotoxicity immunosuppressive microenvironments t cell subset T cells CYTOTOXICITY
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Dynamic nuclear polarization and chemically induced hyperpolarization:Progress,mechanisms,and opportunities
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作者 Danhua Dai Yangping Liu +1 位作者 Xiao He Jiafei Mao 《Magnetic Resonance Letters》 2025年第3期23-49,共27页
Nuclear magnetic resonance(NMR)spectroscopy is a powerful and broadly used spectroscopic technique for characterizing molecular structures and dynamics.Yet the power of NMR is restricted by its inherently low sensitiv... Nuclear magnetic resonance(NMR)spectroscopy is a powerful and broadly used spectroscopic technique for characterizing molecular structures and dynamics.Yet the power of NMR is restricted by its inherently low sensitivity due to the weak polarization of nuclear spins under conventional experiment conditions.Dynamic nuclear polarization(DNP)and chemically induced dynamic nuclear polarization(CIDNP)have been emerging as powerful in-situ hyperpolarization methods to boost NMR sensitivity.This review provides a brief overview of DNP mechanisms in the context of both solid-state and liquidstate.We delve into the molecular features of different polarizing agents and their impacts on DNP applications,which are now steadily progressing towards modern NMR magnetic field strengths and ambient temperatures.Furthermore,the progress of CIDNP,particularly photo-CIDNP as a potential alternative hyperpolarization technique of DNP,in studying protein dynamics and chemical reaction mechanisms,will be covered.This review also highlights the chemical diversity and experimental strategies crucial for these hyperpolarization techniques,showcasing their transformative role in NMR spectroscopy. 展开更多
关键词 Dynamic nuclear polarization(DNP) NMR spectroscopy Chemically induced dynamic nuclear polarization(CIDNP) RADICAL Cross effect Solid effect Overhauser effect
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Inconsistent capacity of potential HONO sources to enhance secondary pollutants:Evidence from WRF-Chem modeling
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作者 Jingwei Zhang Haiyan Ran +13 位作者 Yu Qu Chaofan Lian Weigang Wang Yusheng Zhang Feixue Zheng Xiaolong Fan Dawei Lu Chao Yan Kaspar RDaellenbach Zhiqiang Ma Yongchun Liu Maofa Ge Markku Kulmala Junling An 《Journal of Environmental Sciences》 2025年第12期812-830,共19页
Nitrous acid(HONO)is a crucial source of OH radicals in the troposphere,significantly enhancing secondary pollutants like secondary organic aerosols(SOA)and peroxyacetyl nitrates(PAN).While prior research has examined... Nitrous acid(HONO)is a crucial source of OH radicals in the troposphere,significantly enhancing secondary pollutants like secondary organic aerosols(SOA)and peroxyacetyl nitrates(PAN).While prior research has examined HONO sources and their total impacts on secondary pollution,the specific enhancement capacity of each individual HONO source remains underexplored.This study uses observational data from 2015 to 2018 for HONO,SOA,and PAN across six sites in China,combined with WRF-Chem model adding six potential HONO sources to evaluate their capacity:traffic emissions(E_traffic),soil emissions(E_soil),indoor-outdoor exchange(E_indoor),nitrate photolysis(P_nit),and NO_(2) heterogeneous reactions on aerosol and ground surfaces(Het_a,Het_g).The simulated HONO contributions near the ground in urban Beijing were:12%from NO+OH(default source),10%-20%from E_traffic,1%-12%from P_nit,2%-10%from Het_a,and 50%-70% from Het_g.For SOA and PAN,we calculated incremental contributions enhanced by each HONO source and derived enhancement ratios(ERs)normalized against HONO’s contribution:~7 for P_nit,~2 for Het_a,~0.9 for Het_g,~0.8 for E_soil,~0.3 for E_traffic,and~0.1 for E_indoor.HONO sources’capacity to enhance secondary pollutants varies,being larger for aerosol-related sources.Vertical analysis on HONO concentration,spatial distribution,RO_(x) radical cycling rates,and OH enhancements revealed that aerosol-related HONO sources,especially P_nit,contribute more to secondary pollution.Future research should focus more on assessing real-world impacts of HONO sources,besides identifying their budgets.Additionally,uptake coefficient(γ)and nitrate photolysis frequency(J_(nitrate))critically affect HONO and secondary pollutant formation,necessitating further investigations. 展开更多
关键词 Nitrous acid WRF-Chem Secondary organic aerosols Peroxyacetyl nitrate Atmospheric oxidation capacity Vertical profiles
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Recent progress on surface chemistryⅡ:Property and characterization
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作者 Xin Li Zhen Xu +63 位作者 Donglei Bu Jinming Cai Huamei Chen Qi Chen Ting Chen Fang Cheng Lifeng Chi Wenjie Dong Zhenchao Dong Shixuan Du Qitang Fan Xing Fan Qiang Fu Song Gao Jing Guo Weijun Guo Yang He Shimin Hou Ying Jiang Huihui Kong Baojun Li Dengyuan Li Jie Li Qing Li Ruoning Li Shuying Li Yuxuan Lin Mengxi Liu Peinian Liu Yanyan Liu Jingtao Lü Chuanxu Ma Haoyang Pan JinLiang Pan Minghu Pan Xiaohui Qiu Ziyong Shen Qiang Sun Shijing Tan Bing Wang Dong Wang Li Wang Lili Wang Tao Wang Xiang Wang Xingyue Wang Xueyan Wang Yansong Wang Yu Wang Kai Wu Wei Xu Na Xue Linghao Yan Fan Yang Zhiyong Yang Chi Zhang Xue Zhang Yang Zhang Yao Zhang Xiong Zhou Junfa Zhu Yajie Zhang Feixue Gao Yongfeng Wang 《Chinese Chemical Letters》 2025年第1期8-57,共50页
Surface with well-defined components and structures possesses unique electronic,magnetic,optical and chemical properties.As a result,surface chemistry research plays a crucial role in various fields such as catalysis,... Surface with well-defined components and structures possesses unique electronic,magnetic,optical and chemical properties.As a result,surface chemistry research plays a crucial role in various fields such as catalysis,energy,materials,quantum,and microelectronics.Surface science mainly investigates the correspondence between surface property and functionality.Scanning probe microscopy(SPM)techniques are important tools to characterize surface properties because of the capability of atomic-scale imaging,spectroscopy and manipulation at the single-atom level.In this review,we summarize recent advances in surface electronic,magnetic and optical properties characterized mainly by SPM-based methods.We focus on elucidating theπ-magnetism in graphene-based nanostructures,construction of spin qubits on surfaces,topology properties of surface organic structures,STM-based light emission,tip-enhanced Raman spectroscopy and integration of machine learning in SPM studies. 展开更多
关键词 Surface chemistry Scanning probe microscopy π-Magnetism Spin qubits Tip-enhanced Raman spectroscopy
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树枝化对聚芴类分子发光行为的影响 被引量:2
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作者 吴义室 黎静 +5 位作者 艾希成 付亚琴 周建军 李林 薄志山 张建平 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2007年第10期1925-1928,共4页
运用稳态吸收、稳态荧光光谱及皮秒时间分辨荧光光谱等手段,研究了树枝化对聚芴分子的光谱动力学行为的影响.在1×10-5mol/L四氢呋喃溶液中,非树枝化聚芴和不同代数的树枝化聚芴的稳态吸收和稳态荧光光谱基本一致,表明树枝化不影响... 运用稳态吸收、稳态荧光光谱及皮秒时间分辨荧光光谱等手段,研究了树枝化对聚芴分子的光谱动力学行为的影响.在1×10-5mol/L四氢呋喃溶液中,非树枝化聚芴和不同代数的树枝化聚芴的稳态吸收和稳态荧光光谱基本一致,表明树枝化不影响聚芴基团的本征电子性质;在薄膜状态下,紧密排列的聚芴分子表现出明显的链间聚集行为.不同代数树枝化聚芴的时间分辨荧光动力学研究结果表明,溶液状态下的发光为单指数衰减行为,而薄膜状态下的发光为多指数衰减行为,且其发光寿命随树枝化代数增加而增长,表明树枝化基团抑制了邻近的聚芴分子之间能量传递所致的激发态能量耗散. 展开更多
关键词 聚芴 树枝化 能量传递 时间分辨荧光
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微纳米结构导电聚合物合成方法研究进展 被引量:1
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作者 王纲 高彩艳 +1 位作者 王新 陈光明 《高分子通报》 CAS CSCD 北大核心 2014年第10期1-12,共12页
具有纳微米结构的导电聚合物作为一种重要的新型有机功能材料,近年来已迅速发展成为有机聚合物材料科学领域的主要研究热点之一。本文从化学法和电化学法两种主要的可控合成方法角度,详细综述了具有不同形貌及尺寸微纳米结构的导电聚合... 具有纳微米结构的导电聚合物作为一种重要的新型有机功能材料,近年来已迅速发展成为有机聚合物材料科学领域的主要研究热点之一。本文从化学法和电化学法两种主要的可控合成方法角度,详细综述了具有不同形貌及尺寸微纳米结构的导电聚合物的合成方法与合成过程的研究进展。在这两种合成方法中,又进一步分为硬模板法、软模板法和无模板自组装法三个重要方面。另外,讨论了目前文献中对这些方法得到的微纳米结构导电聚合物的形成机理。 展开更多
关键词 导电聚合物 微纳米结构 合成
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Development Trends and Priority Research Fields of Electrochemical Discipline in the 15th Five Year Plan Period
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作者 Lin Zhuang Wen-Bin Cai +36 位作者 Heng-Xing Ji Qing Li Gong-Wei Wang Sen Xin Qing Zhao Fang-Yi Cheng Yu-Guo Guo Lan-Qun Mao Yang Tian Fei Wu Li-Min Zhang Yan Xiang Jin-Song Hu Rui Cao Li Xiao Hua-Bing Tao Wei Xing Dong-Ping Zhan Hong-Gang Liao Mei-Ling Xiao Bin Ren Zhang-Quan Peng Rui Wen Xiang Wang Yue-Feng Song Hou-Fu Lv Bao-Yu Xia Guo-Xiong Wang Jun Cheng Zhi-Pan Liu Min Zhou Bing Huang Cun-Pu Li Yu-Qin Zou Shuang-Yin Wang Hai-Bo Lin Zi-Dong Wei 《电化学(中英文)》 北大核心 2025年第10期84-115,共32页
In fulfillment of the national science-and-technology development agenda, the Department of Chemical Sciences of the National Natural Science Foundation of China (NSFC) convened the Strategic Symposium on the Fifteent... In fulfillment of the national science-and-technology development agenda, the Department of Chemical Sciences of the National Natural Science Foundation of China (NSFC) convened the Strategic Symposium on the Fifteenth FiveYear (20262030) Development Plan for Electrochemistry held in Xiamen on 29 August, 2025-the culminating year of the Fourteenth Five-Year (2021-2025) Development Plan. More than forty leading experts in the field of electrochemistry participated with spanning nine thematic fronts: Interfacial Electrocatalysis, Interfacial Electrochemistry for Energy Storage, Bioelectrochemistry, Electrochemistry of Hydrogen Energy, Electrochemical Micro-/Nano-Manufacturing, Operando Electrochemical Characterization, Electro-Thermal Coupling Catalysis, Theoretical and Computational Electrochemistry,and Electrochemical Synthesis. The forum assembled China's foremost electrochemical expertise to blueprint high-quality disciplinary growth for the coming five-year period, thereby serving overarching national strategic needs and sharpening the international competitiveness of Chinese electrochemistry.This paper is presented to highlight the strategic needs and priority areas for the next five years (2026-2030) based on this symposium. The development status of basic research and applied basic research in China's electrochemistry field is systematically reviewed. The in-depth analyses of the existing problems and key challenges in the research and development of electrochemistry related fields are outlined, and the frontier research areas and development trends in the next 5-10 years by integrating national major strategic needs are discussed, which will further promote the academic community to reach a clearer consensus. The proposed strategic roadmap is intended to accelerate a sharpened community consensus, propel the discipline toward high-quality advancement, and furnish a critical reference for building China into a world-leading science and technology power. 展开更多
关键词 energy storage ELECTROCHEMISTRY strategic symposium chemical sciences interfacial electrocatalysis hydrogen energy BIOELECTROCHEMISTRY electrochemical micro nano manufacturing
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3-(噻吩-2-基)-β-内酰胺的合成及其立体化学 被引量:2
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作者 李伯男 梁勇 +3 位作者 焦雷 胡立博 杜大明 许家喜 《化学学报》 SCIE CAS CSCD 北大核心 2007年第16期1643-1648,共6页
Staudinger反应是合成β-内酰胺类化合物最重要的方法之一.3-(噻吩-2-基)-β-内酰胺是一类重要的β-内酰胺类衍生物.发展了一种从1-(噻吩-2-基)-4,4,4-三氟-1,3-丁二酮和对甲苯磺酰叠氮方便地制备1-(噻吩-2-基)-2-重氮基乙酮的新方法,利... Staudinger反应是合成β-内酰胺类化合物最重要的方法之一.3-(噻吩-2-基)-β-内酰胺是一类重要的β-内酰胺类衍生物.发展了一种从1-(噻吩-2-基)-4,4,4-三氟-1,3-丁二酮和对甲苯磺酰叠氮方便地制备1-(噻吩-2-基)-2-重氮基乙酮的新方法,利用1-(噻吩-2-基)-2-重氮基乙酮加热分解生成的噻吩-2-基烯酮参与的Staudinger反应合成了一系列3-(噻吩-2-基)-β-内酰胺衍生物,并研究了噻吩-2-基烯酮参与的Staudinger反应的立体选择性.实验结果表明噻吩-2-基烯酮是比苯基烯酮更富电子的Moore烯酮,其电子性质介于对甲氧基苯基烯酮和对甲基苯基烯酮之间. 展开更多
关键词 Β-内酰胺 Staudinger反应 立体选择性 重氮酮 烯酮
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