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Constructing Pr-doped CoOOH catalytic sites for efficient electrooxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第1期 234-244页

作者： Botao Fan Hao Zhang Bang Gu Feng qiu qiue Cao Wenhao Fang School of Chemical Science and Technology Yunnan University National Center for International Research on Photoelectric and Energy materials School of Materials and Energy Yunnan University

Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high current ***,a Pr-doped Co（OH）2hexagonal sheet （Pr/Co=1/9,in mole） is synthesized by electrodeposition as highly performant catalyst for 5-hydroxymethylfurfural （HmF） oxidation reaction（HmFOR） to produce 2,5-furandicarboxylic acid （FDCA）.This novel and low-cost catalyst possesses a rather low onset potential of 1.05 V （***） and requires only 1.10 V （***） to reach a current density of 10 mA cm-2for HmFOR,significantly outperforming Co（OH）2benchmark (i.e.,210 mV higher to reach10 m A cm-2).The origin of Pr promotion effect as well as the evolution of CoOOH catalytic sites and HmFOR process has been deeply elucidated by physical characterizations,kinetic experiments,in situ electrochemical techniques,and theoretical *** unique Pr-ameliorated CoOOH active centers enable 100%conversion of HmF,99.6%selectivity of FDCA,and 99.7%Faraday efficiency,with a superior cycling durability toward *** can be one of the most outstanding results for Co-based HmFOR catalysts to date in the *** this work can help open up new horizons for constructing novel and efficient Co-based electrocatalysts by the utilization of lanthanide elements.

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Raman Scattering Study of PbSe Grown on(111)BaF_(2) Substrate

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Chinese Physics Letters 2000年第8期17卷 606-608页

作者： YANG Ai-ling WU Hui-Zhen LI Zhi-Feng qiu Dong-Jiang CHANG Yong LI Jian-Feng P.J.mcCann x.m.Fang Department of Information Science and Electronic Engineering Department of Physics Zhejiang UniversityHangzhou 310028 Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083 The University of Oklahoma NormanOklahoma73019-23USA

PbSe films were grown on(111)-oriented BaF_(2)substrates by using molecular beam *** resolution x-ray diffraction characterization showed good crystalline quality of PbSe *** longitudinal optical phonon at 135cm^(-1)and transverse optical phonon at 47.6cm-1 were observed by Raman scattering *** Raman tensor calculation demonstrates that both transverse-optical and longitudinal-optical(LO)phonons in PbSe crystal are Raman active on(111)-oriented surface,Furthermore,2LO phonon at about 270cm^(-1)and polaron at about 800cm^(-1)in PbSe,were also *** observed Raman frequencies are in good agreement with theoretical calculations using point ion model.

关键词： scattering transverse phonon

Carbon materials toward efficient potassium storage:Rational design,performance evaluation and potassium storage mechanism

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Green Energy & Environment 2023年第1期8卷 115-140页

作者： Daping qiu Yanglong Hou Beijing Key Laboratory for magnetoelectric materials and Devices Beijing Innovation Centre for Engineering Science and Advanced TechnologySchool of Materials Science and EngineeringPeking UniversityBeijing100871China

Potassium-ion batteries(PIBs)are potential“Beyond Li-ion Batteries”candidates for their resource advantage and low standard electrode *** date,the research on PIBs is in its early stages,the most urgent task is to develop high-performance electrode materials and reveal their potassium storage *** PIBs anode materials,carbon with tunable microstructure,excellent electrochemical activity,nontoxicity and low price is considered as one of the most promising anode materials for *** some breakthrough works have emerged,the overall electrochemical performance of the reported carbon anode is still far away from practical ***,we carry out a comprehensive overview of PIBs carbon anode in terms of three aspects of rational design of structure,performance evaluation criteria and characterization of potassium storage ***,the regulation mechanism of key structural features of carbon anode on its potassium storage performance and the representative structural regulation strategies are ***,in view of the undefined performance evaluation criteria of PIBs carbon anode,a reference principle for evaluating the potassium storage performance of carbon anode is ***,the advanced characterization techniques for the potassium storage mechanism of carbon anode are *** review aims to provide guidance for the development of practical PIBs anode.

关键词： Potassium-ion batteries Carbon anode Structural engineering Performance evaluation Potassium storage mechanism

Consumer Entry: Impact on Expert's Pricing and Overcharging Behavior

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Journal of Systems Science and Systems Engineering 2021年第2期30卷 236-250页

作者： Qijun qiu Li Jiang School of management Science and Engineering Nanjing University of Information Science&TechnologyNcinjing 210044China Faculty of Business The Hong Kong Polytechnic UniversityHong Kong SARChina

In a credence goods market,a consumer(he)is unaware of his true need,w hich can be either intense or minor.A n expert(she)designs a menu that either charges a u n iform price to both services,termed pooling pricing,or varies charges according to service types,termed differential *** the menu offered by the expert and anticipating her behavior in serving consumers,a consumer weighs the expected u tility of service provision against the cost incurred in transportation to decide w hether to visit the expert,termed entry *** arrival of a consumer,the expert discerns his true need and recommends a service along w ith the associated *** the lia b ility assumption,the expert provides a service to satisfy the consumer's ***,the consumer is unable to discern the nature of the service actually *** can induce the expert w ho adopts differential pricing to recommend intense service to a consumer w ith m inor need,termed *** investigate the effects of consumers'entry decision on the expert's optim al pricing strategy and the occurrence of overcharging,and study the robustness of the main results to practical features.

关键词： Credence goods consumer entry overcharging pricing competition

Effects of Zr/mo addition on He bubble formation in Y_(2)O_(3)-added W alloys

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Tungsten 2022年第3期4卷 203-211页

作者： qiu xu m.miyamoto Lai-ma Luo Institute for Integrated Radiation and Nuclear Science Kyoto UniversityOsaka590-0494Japan Shimane University Shimane690-8504Japan School of materials Science and Engineering Hefei University of TechnologyHefei230031China

To improve the mechanical properties of the Y_(2)O_(3)-added W alloy,mo and Zr were independently added to a sample of W-Y_(2)O_(3).In this study,the effects of minor additions of elemental mo and Zr on He bubble formation in the Y_(2)O_(3)added W alloys were investigated at 773 K,973 K,and 1173 K,where the maximum irradiation fluence of the samples using 5 keV He ions was 1.8×10^(21) He m^(−2).He bubbles were observed at all temperatures for both alloys;however,the irradiation fluences at which He bubbles could be observed differed at each *** increase in irradiation temperature,the He irradiation fluence for which the formation of He bubbles could be observed *** the relatively low temperature of 773 K,the void swelling in the W-mo-Y_(2)O_(3)and W-Zr-Y_(2)O_(3)alloys was slightly lower than that of W-Y_(2)O_(3)***,at high temperature of 973 K and 1173 K,the He irradiation resistances of both W-mo-Y_(2)O_(3)and W-Zr-Y_(2)O_(3)were worse than that of W-Y_(2)O_(3).The addition of Zr enhanced the interaction between vacancies and He,enhancing the formation of He ***,the addition of mo coarsened the Y_(2)O_(3)particles,reducing the suppression of vacancy cluster formation due to the dispersion of Y_(2)O_(3)*** is,therefore,necessary to fully consider mechanical properties and T-retention in addition to the irradiation resistance of He to select an alloy as the plasma-facing material for fusion applications.

关键词： W-Y_(2)O_(3)alloy He bubble mo Zr

Removal of Cd(Ⅱ)from dilute aqueous solutions by complexation–ultrafiltration using rotating disk membrane and the shear stability of PAA–Cd complex

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Chinese Journal of Chemical Engineering 2019年第3期27卷 519-527页

作者： Liang Chen Yunren qiu School of Chemistry and Chemical Engineering Central South University

Removal of cadmium(Ⅱ) ions from dilute aqueous solutions by complexation–ultrafiltration using rotating disk membrane was investigated. Polyacrylic acid sodium(PAAS) was used as complexation agent, as key factors of complexation, pH and the mass ratio of PAAS to Cd^(2+)(P/m) were studied, and the optimum complexation–ultrafiltration conditions were obtained. The effects of rotating speed(n) on the stability of PAA–Cd complex was studied with two kinds of rotating disk, disk Ⅰ(without vane) and disk Ⅱ(with six rectangular vanes) at a certain range of rotating speed. Both of the rejection could reach 99.7% when n was lower than 2370 r·min^(-1) and 1320 r·min^(-1), for disk I and disk Ⅱ, respectively. However, when rotating speed exceeds a certain value,the critical rotating speed(n_c), the rejection of Cd(Ⅱ) decreases greatly. The distribution of form of cadmium on the membrane was established by the membrane partition model, and the critical shear rate(γ_c), the smallest shear rate at which the PAA–Cd complex begins to dissociate, was calculated based on the membrane partition model and mass balance. The critical shear rates(γ_c) of PAA–Cd complex were 5.9 × 10~4 s^(-1), 1.01 × 10~5 s^(-1),and 1.31 × 10~5 s^(-1) at pH = 5.0, 5.5, and 6.0, respectively. In addition, the regeneration of PAAS was achieved by shear induced dissociation and ultrafiltration.

关键词： Complexation-ultrafiltration membrane Regeneration Shear stability Critical shear rate Shear induced dissociation

An Analyses of Internal magnetic Field in moment Actuator

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Chinese Physics Letters 1995年第7期12卷 442-445页

作者： qiu Shuye B.m.Gibbs Department of Physics Shantou universityShantou 51506 Acoustics Research Unit Liverpool UniversityP.O.BOX 147Liverpool L693BXU.K.

A medium size moment actuator is *** consists of two parallel identical magnetostrictive *** biases with parallel and series magnetic paths,respectively,are *** for a branch of the parallel magnetic paths is *** coefficients from electrical to mechanical energy for three prototype moment actuators with different magnetic paths are measured to support the analyses for the internal magnetic field of the actuator in theory.

关键词： theory. magnetic Internal

Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第01期 157-162页

作者： Rong-De He Yun-Lei Luo qiu-Quan Pan Qi-Wei Yao xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–m. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

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Revisiting the mass–Size Relation of Structures in molecular Clouds

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Research in Astronomy and Astrophysics 2022年第7期22卷 118-127页

作者： Yuchen xing Keping qiu School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210023China

We revisit the mass–size relation of molecular cloud structures based on the column density map of the Cygnus-x molecular cloud *** extract 135 column density peaks in Cygnus-x and analyze the column density distributions around these *** averaged column density profiles,N(R),around all the peaks can be well fitted with broken power-laws,which are described by an inner power-law index n,outer power-law index m,and the radius RTP and column density NTP at the transition *** then explore the m–R relation with different samples of cloud structures by varying the N(R)parameters and the column density threshold,N0,which determines the boundary of a cloud *** find that only when N0 has a wide range of values,the m–R relation may largely probe the density distribution,and the fitted power-law index of the m–R relation is related to the power-law index of N(R).On the contrary,with a constant N0,the m–R relation has no direct connection with the density distribution;in this case,the fitted power-law index of the m–R relation is equal to 2(when N_(0)≥N_(TP) and n has a narrow range of values),larger than 2(when N_(0)≥N_(TP) and n has a wide range of values),or slightly less than 2(when N_(0)

关键词： methods:analytical methods:data analysis ISm:clouds ISm:structure