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71.
Oxygen anion redox reaction provides a high theoretical capacity for Li-rich manganese-based cathodes.However, irreversible surface oxygen release often results in further oxygen loss and exacerbates the decomposition of the electrolyte, which could reduce the capacity contribution from the anionic redox and produce more acidic substances to corrode the surface of the material. In this paper, the surface oxygen release is suppressed by moderating oxygen anion redox activity via constructing chem...  相似文献   
72.
Despite the existence of plentiful photocatalyst heterojunctions, their separation efficiency and charge flow precision remain low on account of lacking interfacial modulation. Herein, through a defect-induced heterojunction constructing strategy, Ni4Mo alloys were in-situ grown on the unsaturated coordinated sulfur atoms of sulfur vacancies-rich ZCS(Sv-ZCS) via interfacial Ni-S covalent bonds. The experimental and theoretical results reveal that these unsaturated sulfur atoms induced...  相似文献   
73.
The electrochemical hydrogenation of HMF to BHMF is an elegant alternative to the conventio nal thermocatalytic route for the production of high-value-added chemicals from biomass resources.In virtue of the wide potential window with promising Faradic efficiency(FE) towards BHMF,Cu-based electrode has been in the center of investigation.However,its structure-activity relationship remains ambiguous and its intrinsic catalytic activity is still unsatisfactory.In this work,we develop a two-step oxi...  相似文献   
74.
The development of potential transition-metal carbide/nitride heterojunctions is hindered by overall understanding and precise modulation for heterointerface effects.Herein,we demonstrate that Mo2C/Mo2N heterojunction with the precisely regulated high-quality interface can achieve marvelous rate performance and energy output via enlarging the interface-effect range and maximizing "accelerated charge" amount The heterointerface mechanism improving properties is synergistical...  相似文献   
75.
The development of efficient metal-zeolite bifunctional catalysts for catalytic fast pyrolysis(CFP) of biomass waste is highly desirable for bioenergy and renewable biofuel production.However,conventional metal-loaded zeolites often suffer from metal sintering during pyrolysis and are thus inactivated.In this study,single-site Ga-functionalized hollow ZSM-5(GaOx@HS-Z5) was synthesized via an impregnationdissolution-recrystallization strategy without H2 reduction.The Ga atom...  相似文献   
76.
Colorimetric sensing strategies as a powerful point-of-care testing(POCT) tool have attracted significant interest in various chem/biosensing applications.Taking the excellent bare-eye-detectable signaling feature,nanozymes-based colorimetric sensors enable more potential applications and have been a new forefront in the colorimetric POCT analysis toward different target analytes.However,the low catalytic activity of nanozymes in most cases limits their practical application.Recent efforts demonstrate that the aggregation-induced nanozymes provide a general means to modulate nanozymes activity and enhance colorimetric sensing performances of some nanozymes-based colorimetric sensors.But there are few reports are explored to discuss and review such aggregation-induced nanozymes and their colorimetric sensing applications.To highlight the advances and progress in aggregation-induced nanozymes based colorimetric assays,we herein summary the fundamentals,classify and applications of this newlydeveloping field,focusing on the aggregation-induced activity enhancement of nanozymes(AIAEnanozymes) with a significant "signal-on" feature and aggregation-induced activity inhibition of nanozymes(AIAI-nanozymes) with a dramatical "signal-of" characteristics.Finally,we also propose the current challenges and the future prospects on both AIAE-nanozymes and AIAI-nanozymes.  相似文献   
77.
Two different skeletons of heterocyclic compounds,quinoline and quinazolinone analogs could be obtained by a novel one-pot synthesis from substituted 3-amino-1 H-benzo[f]chromene-2-carbonitrile derivatives and cyclohexanone in DMF in the catalyst of anhydrous zinc chloride under reflux.A plausible mechanism was proposed.  相似文献   
78.
In order to find new urea cytokinins, a series of novel fluorinated heteroaromatic ureas have been designed and synthesized. The crystal structure of 3g was further determined by single crystal X-ray diffraction to obtain the structural feature of this class of urea compounds. The preliminary bioassay showed that some title compounds have good cytokinin activity.  相似文献   
79.
A high active novel TiO2/AC composite photocatalyst was prepared and used for phenol degradation. It was much more active than P-25 and exhibiting good decantability, less deactivation after several runs and less sensitive to pH change. Diffuse reflectance spectra (DRS) revealed that the electronic change in TiO2 did not occur by the addition of AC. Results of SEM and XRD suggested that better TiO2 distribution can be achieved when optimal AC content was adopted. The performance of the prepared TiO2/5AC catalyst revealed great practical potential in wastewater treatment field.  相似文献   
80.
Aiphanol was isolated from the seeds of Aiphanes aculeate Willd. (Arecaceae) collected in Peru and was reported to exhibit significant inhibitory activities against cyclooxyge- nases-1 and -2. The structure of aiphanol was elucidated by spectroscopic methods as an unprecedented stilbenolignan skeleton in which a stilbene moiety is linked to a phenylpropane unit through a dioxane bridge1. In our previous works the synthetic approach to 1,4-benzodioxane lignans were achieved2. Since aiphanol…  相似文献   
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