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Different effect of li^(+),Na^(+),K^(+)-doping on crystal structure and electrical property of Sr_(0.6)Ba_(0.4)Nb_(2.O_(6)

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Journal of Materiomics 2024年第5期10卷 1071-1079页

作者： Jian guo Xinrui Yang Yulong Yang Shuting Pang Shan-Tao zhang {2. Yang National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences&Jiangsu Key Laboratory of Artificial Functional Materials&Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210023China Nanjing University(Suzhou)High-tech Institute Suzhou Industrial Park215123China School of Physics Nanjing UniversityNanjing210093China Functional Materials and Acousto-Optic Instruments Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin150080China

Ferroelectric Sr_(0.6)Ba_(0.4)Nb_(2.O_(6)(SBN)shows typical unfilled tetragonal tungsten bronze structure where 1/6 A sites and all C sites are *** presence of such structural vacancy provides the possibility to further modulate the crystal structure and electrical *** this work,alkali ions(li^(+),Na^(+),K^(+))doped SBN ceramics have been fabricated via solid-solution reaction *** general,each doping promotes the crystal structure evolves from unfilled toward filled tungsten ***,the different doping ion radius causes the differences in occupying initial structural vacancies,resulting in significantly different electrical properties,li^(+)doping enhances relaxor characteristic whereas Na+and K^(+)doping lead to normal ferroelectric behavior,accompanying an increase in Curie temperature(TC)from 36℃ of SBN to 40,2.2.148℃ of li^(+),Na^(+)and K^(+)doping,*** from improved relaxor degree and high density,the li^(+)doped SBN displays a good energy storage *** the ratio of Sr/Ba and(Sr+Ba)/Nb has not been changed,this work presents direct evidence for the effect of structural vacancy on crystal structure and properties,as well as inspiration for further work on unfilled tungsten bronze.

关键词： Sr_(0.6)Ba_(0.4)Nb_(2.O_(6) oxides Structural vacant Alkali ions doping

Pd cluster decorated free standing flexible cathode for high performance li-oxygen batteries

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Nano Research 2024年第4期17卷 2678-2686页

作者： liang guo guoliang zhang Ruonan Yang Dongmei zhang Xiuqi zhang Han Yu Xia li Feng Dang Key Laboratory for liquid-Solid Structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

As a promising candidate for the next generation energy storage system,rechargeable lithium-oxygen batteries(LOBs)still face substantial challenges caused by insulating discharge products that preclude their practical *** highly efficient cathode catalysts capable of facilitating formation/decomposition of discharge products is considered as an essential approach towards high performance ***,Pd decorated Te nanowires(Pd@Te NWs)were synthesized as advanced catalyst in LOBs to maximize Pd utilization and achieve synergistic effect,in which Pd clusters were uniformly grown on Te substrate though regulating the Pd:Te ***,Pd@Te nanowires assembled into an interpenetrating network-like structure by vacuum filtration and employed as flexible cathode,enabling LOBs achieved an ultralong 190 cycles stability and a superior specific capacity of 3.35 mAh·cm^(-2..Experimental studies and density functional theory(DFT)calculations reveal the excellent catalytic ability of Pd@Te and synergistic catalytic mechanism of Pd and Te,in which uniform electron distribution,extensive electron exchange,and large adsorption distance between Pd cluster and discharge products promote homogeneous adsorption/desorption of discharge products,while the high adsorption energy of Te substrate for li species reduces the initial dynamical energy barrier during discharging *** current work provides viable strategy to design composite catalysts for flexible cathode of LOBs with synergistic catalytic effects.

关键词： flexible lithium-oxygen batteries Pd@Te synergistic catalysis cathode catalysts density functional theory(DFT)calculation

Spatio-temporal evolution and topographic gradient effect of land use and ecosystem service value in the Lhasa River Basin

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Journal of Mountain Science 2024年第6期21卷 2059-2074页

作者： ZHOU Jianwei FENG bin WU Hua XU Tong CHEN linna ZHAO Xinyong {2. Qiyun li Jiatong zhang Chenguang ZHU Kangcheng KONG Yuzhong School of Ecology and Environment Tibet UniversityLhasa 850000China School of Engineering Tibet UniversityLhasa 850000China Joint Laboratory of Plateau Surface Remote Sensing Tibet UniversityLhasa 850000China

The Lhasa River Basin forms an essential human settlement area in the southern part of the Qinghai-Tibet *** study employed ecosystem service value(ESV)evaluation model,terrain gradient grading,and Geodetector to analyze land use and ESV in the Lhasa River Basin from 1985 to *** findings reveal that:(1)From 1985 to 2.2.,grassland was the dominant land *** was a trend of grassland reduction and the expansion of other land types.(2.ESV has increased over the research period(with a total increase of 0.84%),with higher values in the southeast and lower values in the *** contributed the most to ESV,and climate regulation and hydrological regulation were the ecosystem services that contribute the most to ESV.(3)Natural factors like NDVI and altitude,as well as economic factors like population density and distance from roads,influenced the spatial differentiation of ESV,the explanatory power of NDVI reached up to *** interaction between factors had a greater impact than individual *** research results can provide theoretical support for national spatial planning and ecological environment protection in the Lhasa River Basin and other similar areas.

关键词： Ecosystem services value Land use Terrain gradient effect Lhasa River Basin Driving factors

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Photochromic radical states in 3D covalent organic frameworks with zyg topology for enhanced photocatalysis

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National Science Review 2024年第7期11卷 177-188页

作者： Tian-Tian Ma guo-zhang Huang Xiao-Han Wang Yan {2.ang Run-Han {2. bin Wang Su-Juan Yao Jia-Peng {2.ao Shun-{2. {2. Yong Yan Ya-Qian Lan School of Chemistry South China Normal University Department of Chemistry Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology

Covalent-organic frameworks（COFs） with photoinduced donor-acceptor（D-A） radical pairs show enhanced photocatalytic activity in principle. However, achieving long-lived charge separation in COFs proves challenging due to the rapid charge recombination. Here, we develop a novel strategy by combining[6 + 4] nodes to construct zyg-type 3D COFs, first reported in COF chemistry. This structure type exhibits a fused Olympic-rings-like shape, which provides a platform for stabilizing the photoinduced D-A radical pairs. The zyg-type COFs containing catalytically active moieties such as triphenylamine and phenothiazine（PTZ） show superior photocatalytic production rates of hydrogen peroxide（H2.2.. Significantly, the photochromic radical states of these COFs show up to 400% enhancement in photocatalytic activity compared to the parent states, achieving a remarkable H2.2.ynthesis rate of 332. μmol g-1h-1, which makes the PTZ-COF one of the best crystalline porous photocatalysts in H2.2.roduction. This work will shed light on the synthesis of efficient 3D COF photocatalysts built on topologies that can facilitate photogenerating D-A radical pairs for enhanced photocatalysis.

关键词： 3D covalent-organic frameworks photochromic radical states donor and acceptor hydrogen peroxide photocatalysis

A deoxidation thermodynamic model for 304 stainless steel considering multiple-components coupled reactions

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Journal of Iron and Steel Research International 2024年第1期31卷 74-91页

作者： Yan Yan Guang-hao Shang li-ping zhang Shao-ying li Han-jie guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Henan Jinhui Stainless Steel Industry Group Co. Ltd.Xuchang461500HenanChina Changge Jinhui Recycling Metal R&D Co. Ltd.Xuchang461500HenanChina

A thermodynamic model for predicting the equilibrium oxygens of 304 stainless steel was developed based on the theory of slag-steel equilibrium,the law of mass conservation,and the ion and molecule coexistence *** the developed model,the Fe-Cr-Mn-Si-Al-S-O-melts reaction system and CaO-MgO-CaF_(2.-FeO-MnO-Al_(2.O_(3)-SiO_(2.-Cr2._(3)slags were *** oxygen contents calculated by the model are in good agreement with experimental results and reference *** equilibrium oxygen contents in 304 stainless steel mainly decrease with increasing binary basicity(w(CaO)/w(SiO_(2.),where w(i)is the mass percentage of component i)and decreasing *** binary basicity at 2.0 while maintaining temperatures lower than 182. K will keep the oxygen contents in the 304 stainless steel lower than 15×10^(-6).The equilibrium oxygen contents may also be decreased with increasing content of MgO in slags,which is more significant at lower binary ***,a small amount of FeO,MnO,and Al_(2.O_(3)(about 0-2.5 wt.%)in slags has little effect on equilibrium oxygen ***,it is found that the[C]-[O]reaction may occur during refining process but will not significantly affect the equilibrium oxygen contents.

关键词： Complex deoxidation Thermodynamic model Ion and molecule coexistence theory 304 stainless steel Slag-steel reaction

The co-transport of Cd(Ⅱ) and nZnO in saturated soil packed column:effects of ionic strength and pH

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Acta Geochimica 2024年第1期43卷 97-109页

作者： Min liao guo {2. Yixin Luo Yuhao zhang Kangyou Hu Xiongxiong Lu Xiaomei Xie College of Environmental and Resource Science Zhejiang UniversityYuhangtang Road No.866Hangzhou 310058China zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition Yuhangtang Road No.866Hangzhou 310058China National Demonstration center for Experimental Environmental and Resources Education(zhejiang University) Yuhangtang Road No.866Hangzhou 310058China

The rapid development and widespread use of ZnO nanoparticles(nZnO) in various industries have raised concerns about their potential environmental ***,understanding the fate and role of nZnO in the natural environment is crucial for mitigating their hazardous effects on the environment and human *** purpose of the present study was to provide scientific support for understanding and eliminating the joint risk of nanoparticle and heavy metal pollution in the soil environment by revealing the co-transport characteristics of Cd(Ⅱ) and ZnO nanoparticles(nZnO) in soil under different ionic strength(IS) and *** impacts of different IS and pH on the co-transport of Cd(Ⅱ) and nZnO in a2. cm long with an inner diameter of 2.5 cm acrylic column packed with 10 cm high soil samples were investigated in the present *** the above system,a500 μg L^(-1) Cd(Ⅱ) loaded nZnO suspension pulse with varying IS or pH was introduced into the soil column for leaching over 5 PVs,followed up by 5 PVs background solutions without *** IS was 1,10,or 50 mM NaCl,with pH6,or the pH was 6,7 or 8 with 1 mM ***,Sedimentation experiments for nZnO,adsorption of Cd(Ⅱ) on soil,and nZnO,DLVO theory calculation for the same background condition were *** presence of nZnO significantly increased the mobility of Cd(Ⅱ) as a result of its strong adsorption capacity for nZnO-associated Cd(Ⅱ).However,with the increase of IS,the co-transport of nZnO and Cd(Ⅱ) was decreased and the retention of nZnO in the soil column due to more nZnO attended to aggregate and sediment during the transport and the decrease in the adsorption capacity of nZnO for Cd(Ⅱ) by competition of Na^(+).When pH was 6,7,and 8,the co-transport of nZnO and Cd(Ⅱ) increased with higher pH due to the lower electrostatic attraction between nZnO and soil under higher ***,the DLVO theory was fitted to describe the above co-transport process of nZnO and Cd(Ⅱ).More attention should be paid to

关键词： ZnO Nanoparticles Cadimium Soil Co-transport

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Tetrahedral framework nucleic acids/hyaluronic acidmethacrylic anhydride hybrid hydrogel with antimicrobial and anti-inflammatory properties for infected wound healing

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International Journal of Oral Science 2024年第3期16卷 436-447页

作者： Cai Qi Qiang Sun Dexuan Xiao Mei zhang Shaojingya Gao bin {2. Yunfeng lin State Key Laboratory of Oral Diseases&National center for Stomatology&National Clinical Research center for Oral Diseases&West china Hospital of Stomatology Sichuan UniversityChengduChina Sichuan Provincial Engineering Research center of Oral Biomaterials ChengduChina Department of Stomatology The First Medical CentreChinese PLA General HospitalBeijingChina

Bacterial resistance and excessive inflammation are common issues that hinder wound *** peptides(AMPs)offer a promising and versatile antibacterial option compared to traditional antibiotics,with additional anti-inflammatory ***,the applications of AMPs are limited by their antimicrobial effects and stability against bacterial *** are regarded as a promising drug delivery platform that could enhance the antibacterial properties and stability of ***,in this study,a composite hydrogel(HAMA/t-GL13K)was prepared via the photocross-linking method,in which tFNAs carry *** hydrogel was injectable,biocompatible,and could be instantly *** exhibited broad-spectrum antibacterial and anti-inflammatory properties by inhibiting the expression of inflammatory factors and scavenging ***,the hydrogel inhibited bacterial infection,shortened the wound healing time of skin defects in infected skin full-thickness defect wound models and reduced *** constructed HAMA/tFNA-AMPs hydrogels exhibit the potential for clinical use in treating microbial infections and promoting wound healing.

关键词： properties. hydrogel anhydride

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Simultaneously enhancing the strength and ductility of as-extruded AlN/AZ91 composites via nano-precipitation and pyramidal slip

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Journal of Materials Science & Technology 2024年第5期172卷 240-254页

作者： bin zhang Yunxia Sun Tuo {2.ang Yunzhen {2. Tian {2. Jingchao Wang Ruiru Cai Chang{2.n Yang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

Age hardening is often used to optimize the mechanical properties of as-deformed Mg-based materials in industry,whereas the improvement of strength is usually accompanied by the significant loss of ductility,which hinders the application of Mg-based materials in structural *** the present work,high strength-ductility synergy(the yield strength of 2.3±9 MPa,ultimate tensile strength of 398±7 MPa and elongation to fracture of 34%±1%)was realized in as-extruded AlN/AZ91 composites after optimiz-ing aging *** characterization shows that AlN particles induced a large number of geometrically necessary dislocations around the AlN/Mg interface during extrusion,which decreased the nucleation barrier and provided more heterogeneous nucleation sites forγ-Mg 17 Al 12.continuous ***,95%of residual dislocations in as-extruded AlN/AZ91 composites were annihilated dur-ing peak-aging,suppressing the growth and coarsening of continuous ***,high density of nano-sizedγ-Mg 17 Al 12.continuous precipitates was produced in as-extruded AlN/AZ91 composites af-ter *** tension,gliding dislocations bypassed sphericalγ-Mg 17 Al 12.nano-precipitates by Orowan looping rather than cutting mechanism,which induced a strong block on dislocation *** high yield strength was mainly attributed to the high density of non-shearableγ-Mg 17 Al 12.nano-precipitates with spherical morphology,which was different from other Mg-Al-based *** results of texture evolution and slip trace analysis demonstrated that the suppression of extension twinning and less basal slip was due to the enhanced activity of pyramidalc+aslip in as-extruded AlN/AZ91 com-posites after peak-aging during the room temperature tension,meanwhile,the dislocation density of as-extruded AlN/AZ91 composites was significantly decreased during peak-aging,then higher elongation to fracture was achieved.

关键词： Magnesium matrix composites Mechanical properties Precipitation Deformation mechanisms Non-basal slip

When quantum dots meet blue phase liquid crystal elastomers:visualized full-color and mechanically-switchable circularly polarized luminescence

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light(Science & Applications) 2024年第6期13卷 1210-1220页

作者： Shan li Yuqi Tang Qingyan Fan Ziyuan li Xinfang {2. Jingxia Wang Jinbao guo Quan li Key Laboratory of Carbon Fibers and Functional Polymers Ministry of Educationand College of Materials Science and EngineeringBeijing University of Chemical Technology100029BeijingChina Institute of Advanced Materials and School of Chemistry and Chemical Engineering Southeast UniversityNanjing211189China Materials Science Graduate Program Kent State UniversityKentOH44242USA CAS Key Laboratory of Bio-Inspired Materials and Interfacial sciences Technical Institute of Physics and ChemistryChinese Academy of Sciences100190BeijingChina

Polymer-based circularly polarized luminescence(CPL)materials with the advantage of diversified structure,easy fabrication,high thermal stability,and tunable properties have garnered considerable ***,adequate and precise tuning over CPL in polymer-based materials remains challenging due to the difficulty in regulating chiral ***,visualized full-color CPL is achieved by doping red,green,and blue quantum dots(QDs)into reconfigurable blue phase liquid crystal elastomers(BPLCEs).In contrast to the CPL signal observed in cholesteric liquid crystal elastomers(CLCEs),the chiral 3D cubic superstructure of BPLCEs induces an opposite CPL ***,this effect is entirely independent of photonic bandgaps(PBGs)and results in a high glum value,even without matching between PBGs and the emission bands of ***,the lattice structure of the BPLCEs can be reversibly switched via mechanical stretching force,inducing on-off switching of the CPL signals,and these variations can be further fixed using dynamic disulfide bonds in the ***,the smart polymer-based CPL systems using the BPLCEs for anti-counterfeiting and information encryption have been demonstrated,suggesting the great potential of the BPLCEs-based CPL active materials.

关键词： circular quantum crystal