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chinese Journal of Chemistry 2024年第9期42卷 973-979页

作者： Ziwei Deng Zhiyi Sun Yaqiong Li Jiajing pei Wenxing chen Energy&Catalysis Center Schoolof Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 00049China

Energy transformation is imminent,and hydrogen energy is one of the important new energy sources.One of the keys to increasing the rate of hydrogen evolution during electrolysis is the use of high-performance catalysts for oxygen evolution reactions(OER).Single-atom alloys(SAAs)have garnered significant attention because they partially reduce costs and combine the advantages of both single-atom catalysts(SACs)and alloy catalysts.Herein,an efficient pyrolysis strategy based on a mixing and drying process is designed to anchor ultra-small Co cluster particles,combined with Ru single atoms dispersed on nitrogen-doped ultra-thin carbon nanosheets(Ru_(1)Co SAA/NC).The prepared electrocatalyst exhibits superior OER activity and superb stability,demonstrating an overpotential of 238 mV for OER with a current density of 10 mA·cm^(-2) in 0.5 mol/L H_(2)SO_(4).And we also utilized in-situ XAS to detect the oxidation state of Ru sites during OER.All in all,this method achieves cost reductions and efficiency improvements through the design of SAAs,offering new prospects for the structural transformation of clean energy.

关键词： Oxygen evolution reaction Single alloy catalyst Ultra-thin carbon nanosheets Electrocatalyst Pyrolysis RuiCo SAA/NC

Role of adaptation measures in addressing heatwave exposure in china

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Advances in Climate Change Research 2024年第1期15卷 148-157页

作者： Qin-Mei HAN Qing-chen CHAO Shao SUN pei-Jun SHI National Climate Centre China Meteorological AdministrationBeijing 100081China State Key Laboratoryof Severe Weather chinese Academy of Meteorological Sciences Beijing 0o08lChina Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China

Heatwave exposure has increased dramatically because of climate warming and population growth,along with their interactive effects.However,effective adaptation measures can reduce these impacts.Nonetheless,the dynamic changes,regional inequality in adaptive capacity and their potential contributions to reducing exposure in the future remain unclear.This study quantifies the impact of adaptive capacity and underscores regional variations in heatwave magnitudes,population exposure and adaptation levels in china.We projected the future adaptive capacity using air-conditioner penetration,factoring in climate cooling requirements and individuals'purchasing power.Utilising population and gross domestic product(GDP)data from four Shared Socioeconomic Pathways(SSP1,SSP2,SSP3 and SSP5)and daily temperature data from four SSP-based emission scenarios(SSP1-2.6,SSP2-4.5,SSP3-7.0 and SSP5-8.5),we estimated heatwave duration,population exposure and avoided impacts through adaptation across china and its sub-regions.Results show a substantial increase in heatwave duration in Southwest and Southern china,especially under the SSP5-8.5 scenario,with a projection of 163.2±36.7 d during 2081-2100.Under the SSP3|SSP3-7.0 scenario,total exposure reaches 156.4±76.8 billion person d per year,which is the highest among all scenarios and 23 times greater than that in 1986-2005 without adaptation.Upon considering adaptation measures,a noteworthy reduction in population exposure is observed,especially in the SSP3|SSP3-7.0 and SSP5JSSP5-8.5 scenarios,with reductions of(62.6±3.9)%and(65.8±5.1)%,respectively,compared with the scenario without adaptation during 2081-2100.Remarkable regional disparities in avoided impacts are also evident,with variations of up to 50%across different regions.The implementation of effective and environmentally friendly adaptation measures can notably address climate change,thereby alleviating the profound threats posed to human well-being.

关键词： Heatwaves Population exposure Adaptation Future projection china

Theoretical screening of cooperative N-bridged dual-atom sites for efficient electrocatalytic nitrogen reduction with remolding insight

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Nano Research 2024年第4期17卷 3413-3422页

作者： Huimei chen Yan Yang chi Jiao Zhiwen Zhuo Junjie Mao Yan Liu Key Laboratory of Functional Molecular Solids Ministry of EducationCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China

The electrocatalytic nitrogen reduction reaction(e-NRR)is a promising alternative method for the Haber–Bosch process.However,it still faces many challenges in searching for high activity,stability,and selectivity catalysts and ascertaining the catalytic mechanism with complete insight.Here,a series of graphene-based N-bridged dual-atom catalysts(M1-N-M2/NC)are systematically investigated via first-principle calculation and a high-throughput screening strategy.The result unveils that N_(2) adsorption on M1-N-M2/NC in bridge-on adsorption mode can effectively break the scaling relationship on single-atom catalysts(SACs).Moreover,V-N-Ru/NC and V-N-Os/NC are systematically screened out as promising e-NRR catalysts,with extremely low limiting potentials of-0.20 and-0.18 V,respectively.Furthermore,the adsorption site competition between*N_(2) and*H,as well as the competitive twin reactions of hydrogen evolution reaction(HER)on intermediates(N_(n)H_(m))during the e-NRR process,is systematically evaluated to form a remodeling insight for the reactions in mechanism,and the e-NRR of new proposed dual-atom catalysts(DACs)is strategically optimized for its high-efficiency performance potential via our remolding insight in e-NRR mechanism.This work provides new ideas and insights for the design and mechanism of e-NRR catalysts and an effective strategy for rapidly screening highly efficient e-NRR catalysts.

关键词： nitrogen reduction dual-atom catalysts high-throughput screening hydrogen evolution reaction density functional theory calculations

Nd:YAG water mist laser treatment for giant gestational gingival tumor: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1974-1979页

作者： Hong-Yu chen Jun-Ji Xu Xiu-Lin Chang pei Wu Department of Stomatology Women and Children's Hospital Affiliated to Ningbo UniversityNingbo 315012Zhejiang ProvinceChina

BACKGROUND This case of gestational gingival tumor is huge and extremely rare in clinical practice.As the growth location of this gingival tumor is in the upper anterior tooth area,it seriously affects the pregnant woman's speech and food,causing great pain to the patient.The use of Nd:YGA water mist laser to remove the gingival tumor resulted in minimal intraoperative bleeding,minimal adverse reactions,and good postoperative healing,which is worthy of clinical promotion and application.CASE SUMMARY The patient,a pregnant woman,reported a large lump in her mouth on the first day of postpartum treatment.Based on medical history and clinical examination,the diagnosis was diagnosed as gestational gingival tumor.Postoperative pathological biopsy also confirmed this diagnosis.The use of Nd:YAG water mist laser to remove the tumor resulted in minimal intraoperative bleeding,clear surgical field of view,short surgical time,and good postoperative healing.CONCLUSION In comparison to traditional surgery,Nd:YAG water mist laser surgery is minimally invasive,minimizes cell damage,reduces bleeding,ensures a clear field of vision,and virtually eliminates postoperative edema,carbonization,and the risk of cross infection.It has unique advantages in oral soft tissue surgery for pregnant patients.Therefore,the clinical application of Nd:YAG water mist laser for the treatment of gestational gingival tumors is an ideal choice.

关键词： Gestational gingival tumor Nd:YAG water mist laser Granulomatous gingival tumor Minimally invasive dentistry Pregnancy related diseases Oral soft tissue surgery Case report

Enhanced mechanical property by introducing bimodal grains structures in Cu-Ta alloys fabricated by mechanical alloying

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Journal of Materials Science & Technology 2024年第5期172卷 104-112页

作者： Ningyu Li Yongqin Chang Mingyang Li Yuxiang chen Xinrui Luo Shichao pei Fan Yang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi’an Rare Metal Materials Institute Co.Ltd Xi’an 710016China

Dispersion-strengthened copper alloys can achieve ultra-high strength,but usually at the expense of duc-tility.In this study,a strategy for overcoming strength-ductility tradeoffof Cu alloys is realized through the introduction of bimodal grains structures.Cu-Ta alloys with only 0.5 at.%Ta content were successfully prepared by mechanical alloying combined with spark plasm sintering.The samples prepared by one-step and two-step ball milling methods are named as Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ),respectively.The microstructural characterizations revealed that ultra-fine equiaxed grains with uniformly dispersed Ta precipitates were obtained in the Cu-Ta alloys.High strength of 377 MPa for yield strength together with elongation of∼8%was obtained in Cu-Ta(Ⅰ).Bimodal grains structures composed of fine-grain zones and coarse-grain zones were successfully introduced into Cu-Ta(Ⅱ)by a two-step ball milling approach,and both yield strength(463 MPa)and elongation(∼15%)were significantly synergistic enhanced.The hardness values of both Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)were almost kept nearly constant with the increase of annealing time,and the softening temperatures of Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)are 1018 and 1013℃,reaching 93.9%and 93.5%T m of pure Cu(1083℃),respectively.It reveals that the Cu-0.5 at.%Ta alloys exhibit excellent thermal stability and exceptional softening resistance.Ta nanoclusters with semi-coherent structures play an essential role in enhancing the strength and microstructural stability of alloys.Bimodal structures are beneficial to the activation of back stress strengthening and the initiation and propagation of microcracks,thus obtaining the extraordinary combination of strength and elongation.This study provides a new way to fabricate dispersion-strengthened Cu alloys with high strength,high elongation,excellent thermal stability and softening resistance,which have potential application value in the field of the future fusion reactor.

关键词： Cu-Ta alloy Mechanical alloying Ta precipitates Bimodal structures Mechanical property

Synergetic optimization operation method for distribution network based on SOP and PV

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Global Energy Interconnection 2024年第2期7卷 130-141页

作者： Lei chen Ning Zhang Xingfang Yang Wei pei Zhenxing Zhao Yinan Zhu Hao Xiao State Grid Shijiazhuang Electric Power Company Shijiazhuang 130100P.R.China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190P.R.China IEEE Power and Energy Society New YorkUSA

The integration of distributed generation brings in new challenges for the operation of distribution networks,including out-of-limit voltage and power flow control.Soft open points(SOP)are new power electronic devices that can flexibly control active and reactive power flows.With the exception of active power output,photovoltaic(PV)devices can provide reactive power compensation through an inverter.Thus,a synergetic optimization operation method for SOP and PV in a distribution network is proposed.A synergetic optimization model was developed.The voltage deviation,network loss,and ratio of photovoltaic abandonment were selected as the objective functions.The PV model was improved by considering the three reactive power output modes of the PV inverter.Both the load fluctuation and loss of the SOP were considered.Three multi-objective optimization algorithms were used,and a compromise optimal solution was calculated.Case studies were conducted using an IEEE 33-node system.The simulation results indicated that the SOP and PVs complemented each other in terms of active power transmission and reactive power compensation.Synergetic optimization improves power control capability and flexibility,providing better power quality and PV consumption rate.

关键词： Synergetic optimization Soft open point(SOP) Photovoltaic(PV) Distribution network

Organic interfacial engineering of gold nanowires for selective glycerol electrooxidation

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chinese Chemical Letters 2024年第3期35卷 502-507页

作者： Zhe Wang Qingling Hong Boqiang Miao Tianjiao Wang Yu Ding Pujun Jin pei chen Yu chen Key Laboratory of Macromolecular Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid Chemistry(Ministry of Education)Shaanxi Key Laboratory for Advanced Energy DevicesSchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an 710062China

The selective electrochemical conversion of glycerol into value-added products is a green and sustainable strategy for the biomass utilization.In this work,Au nanowires(Au-NW)modified with polyethyleneimine(pei)molecule(Au-NW@pei)is obtained by an up-bottom post-modification approach.Physical characterization,molecular dynamics simulation and density functional theory demonstrate that the loose-packed pei monolayer firmly and uniformly distribute on the Au-NW surface due to the strong Au-N interaction.Electrochemical experiments and product analysis display that pei modification significantly enhance the electro-activity of Au-NW for the glycerol electro-oxidation reaction(GEOR)due to the electronic effect.Meanwhile,the steric hindrance and electrostatic effect of pei layer make the optimizing adsorption of intermediates possible.Therefore,the selectivity of C3 product glyceric acid over Au-NW@pei is increased by nearly 20%.The work thus indicates that the rational design of metal-organic interface can effectively elevate the electro-activity and selectivity of Au nanostructures,which may have wide application in biomass development.

关键词： Glycerol electrooxidation reaction Organic interface engineering Gold-based nanomaterials Electrocatalysis Selectivity

Synthesis and potential osteogenic applications of Wnt3a-loaded ZIF-8 nanoparticles

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chinese Chemical Letters 2024年第3期35卷 399-405页

作者： Hengfei Wang Song chen Zihan He Junyu chen Zhou Zhu Qianbing Wan Jian Wang Xibo pei State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesDepartment of ProsthodonticsWest China Hospital of StomatologySichuan UniversityChengdu 610041China Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher EducationStomatological Hospital of Chongqing Medical UniversityChongqing 400016China

The Wnt signaling pathway plays a critical role in bone homeostasis,and the related protein therapy strategies have been reported to have great potential in osseointegration;however,they face formidable challenges such as complex external environments and unavoidable protein denaturation.In this work,we report a novel approach combining the synthesis of metal–organic frameworks(MOFs)and protein encapsulation in a one-pot process based on zeolitic imidazolate framework-8(ZIF-8)and Wnt3a protein,with improved biomechanical behavior and enhanced protein biological response.This combination was designed to enhance the Wnt3a protein function through the improved chemical stability provided by the ZIF-8 crystals.Additionally,the zinc ions contained in the ZIF-8 crystals induced bone homeostasis,further favoring the osteogenesis.The results showed that the Wnt3a protein-loaded ZIF-8 crystals served as efficient drug delivery vehicles to promote osteogenesis,preventing protein denaturation.In particular,Wnt3a-loaded ZIF-8 nanoparticles(Wnt3a@ZIF-8 NPs)had higher efficacy on bone marrow mesenchymal stem cells(BMSCs)than ZIF-8 NPs or Wnt3a proteins,contributing to the osteogenesis through ZIF-8 crystals and intracellular Wnt3a proteins released from Wnt3a@ZIF-8 NPs.Furthermore,polymerase chain reaction(PCR)analysis showed that the osteogenic pathways were upregulated.Overall,the present one-pot process can open up new avenues to develop signaling protein-delivery systems for applications in protein therapy strategies.

关键词： Metal–organic frameworks Nanoparticle Drug release Osteogenesis Bone defects

Efficient and stable PtFe alloy catalyst for electrocatalytic methanol oxidation with high resistance to CO

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Journal of Energy Chemistry 2024年第3期90卷 327-336,I0008页

作者： Qian Yang Sifan Zhang Fengshun Wu Lihua Zhu Guang Li Mingzhi chen An pei Yingliang Feng Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry College of Chemistry and Chemical EngineeringFaculty of Materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou 341000JiangxiChina College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005FujianChina

Direct methanol fuel cells(DMFC) are widely considered to be an ideal green energy conversion device but their widespread applications are limited by the high price of the Pt-based catalysts and the instability in terms of surface CO toxicity in long-term operation.Herein,the PtFe alloy nanoparticles(NPs) with small particle size(~4.12 nm) supported on carbon black catalysts with different Pt/Fe atomic ratios(Pt_(1)Fe_(2)/C,Pt_(3)Fe_(4)/C,Pt_(1)Fe_(1)/C,and Pt_(2)Fe_(1)/C) are successfully prepared for enhanced anti-CO poisoning during methanol oxidation reaction(MOR).The optimal atomic ratio of Pt/Fe for the MOR is 1:2,and the mass activity of Pt_(1)Fe_(2)/C(5.40 A mg_(Pt)^(-1)) is 13.5 times higher than that of conventional commercial Pt/C(Pt/C-JM)(0.40 A mg_(Pt)^(-1)).The introduction of Fe into the Pt lattice forms the PtFe alloy phase,and the electron density of Pt is reduced after forming the PtFe alloy.In-situ Fourier transform infrared results indicate that the addition of oxyphilic metal Fe has reduced the adsorption of reactant molecules on Pt during the MOR.The doping of Fe atoms helps to desorb toxic intermediates and regenerate Pt active sites,promoting the cleavage of C-O bonds with good selectivity of CO_(2)(58.1%).Moreover,the Pt_(1)Fe_(2)/C catalyst exhibits higher CO tolerance,methanol electrooxidation activity,and long-term stability than other Pt_(x)Fe_(y)/C catalysts.

关键词： Alloy catalyst PtFe Methanol oxidation In-situ FTIR CO resistance

Unraveling the mechanism of potassium metal capacitor for highly efficient charge storage

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Science china Chemistry 2024年第5期67卷 1578-1588页

作者： Qianqian Yao pei Tang Kunyao Peng Zhenyuan Miao Yuecong chen Qingyun Dou Xingbin Yan Department of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China South china Academy of Advanced Optoelectronics South China Normal UniversityGuangzhou 510006China

Although hybrid metal ion capacitors(MICs) are highly desired to achieve both high power density of supercapacitors and high energy density of rechargeable batteries, the mismatch problem of electrochemical kinetics of negative and positive electrodes in MICs hampers the realization of this goal. Here, a new hybrid capacitor concept-potassium metal capacitor(PMC) is proposed for the first time, where potassium metal and commercial activated carbon(AC) without any modification are applied as negative and positive electrodes, respectively, and the electrolyte is the same as that of non-aqueous potassium ion batteries. The simplest PMC prototype exhibits a good combination of high energy density(184.9 Wh kg^(-1)) and power density(12.4 kW kg^(-1)), which benefits from the synergistic effect of potassium metal and AC electrode. The former experiences fast potassium plating/striping during charging and discharging, and the later possesses complex multiple charge behaviors driven by low potential of potassium metal. Specifically, below open-circuit voltage, transportation of solvated cations in AC pores plays an important role;beyond this voltage, synergy actions of cations and anions, including adsorption/desorption of solvated cations and anions, and ions exchange between them, dominate the capacitance contribution. This work enriches the types of MICs, and deepens the understanding of the energy storage mechanism of non-aqueous hybrid metal capacitors.

关键词： hybrid capacitor potassium metal activated carbon charge storage mechanism