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Selenate oxyanion-intercalated NiFeOOH for stable water oxidation via lattice oxygen oxidation m.c.anism

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Journal of Energy chemistry 2025年第2期101卷 676-684页

作者： Yijie zhang Weiyi zhang Xiaowen zhang Jinping Li Guang Liu Shanxi Key Laboratory of Gas Energy Efficient and clean Utilization College of Chemical Engineering and Technology Taiyuan University of Technology Shanxi Research Institute of Huai Rou Laboratory

Transition metal-based compounds can serve as pre-catalysts to obtain genuine oxygen evolution reaction（OER） electrocatalysts in the form of oxyhydroxides through electrochem.c.l ***,the role and existence form of leached oxygen anions are still ***,we selected iron selenite-wrapped hydrated nickel molybdate（denoted as NimoO/FeSeO） as a pre-catalyst to study the oxyanion *** is surprising to find that SeO2-exists in the catalyst in the form of intercalation,which is different from previous studies that suggest that anions are doped with residual elements after electrochem.c.l activation,or adsorbed on the catalyst *** experiment and theoretical calculations show that the existence of SeO42-intercalation effectively adjusts the electronic structure of NiFeOOH,promotes intramolecular electron transfer and O-O release,and thus lowers the reaction energy *** expected,the synthesized NiFeOOH-SeO only needs 202 and 285 mV to attain 100 and 1000 mA cm-2in 1 m ***,the anion exchange membrane water electrolyzer（AEmWE） consisting of NiFeOOHSeO anode and Pt/c cathode can reach 1 A cm-2at 1.70 V and no significant attenuation within 300 *** findings provide insights into the m.c.anism,by which the intercalated oxyanions enhance the OER performance of NiFeOOH,thereby facilitating large-scale hydrogen production through AEmWE.

关键词： Anion exchange membrane electrolyzer Industrial current densities Lattice oxygen oxidation Oxyanion intercalation Water splitting

Adsorption of typical NDmA precursors by superfine powdered activated carbon:critical role of particle size reduction

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Journal of Environmental Sciences 2025年第1期147卷 101-113页

作者： Ying Wang Zhichen zhang Zhihang Yin Jun Wang Xiaojian zhang chao chen State Key Joint Laboratory of Environmental Simulation and Pollution control School of EnvironmentTsinghua UniversityBeijing 100084China Research Institute for Environmental Innovation(Suzhou) TsinghuaSuzhou 215163China

control of N-nitrosodimethylamine(NDmA)in drinking water could be achieved by removing its precursors as one practical ***,superfine powdered activated carbons with a diameter of about 1μm(SPAcs)were successfully prepared by grinding powdered activated carbon(PAc,D50=24.3μm)and applied to remove model NDmA precursors,***(RAN)and nizatidine(NIZ).Results fromgrain diameter experiments demonstrated that the absorption velocity increased dramatically with decreasing particle size,and the maximum increase in k2 was 26.8-folds for RAN and 33.4-folds for ***,kinetic experiments explained that rapid absorption could be attributed to the acceleration of intraparticle diffusion due to the shortening of the diffusion ***,performance comparison experiments suggested that the removal of RAN and NIZ(c_(0)=0.5 mg/L)could reach 61.3%and 60%,respectively,within 5 min,when the dosage of SAPc-1.1(D_(50)=1.1μm)was merely 5 mg/L,while PAc-24.3 could only eliminate 17.5%and 18.6%.The adsorption isotherm was well defined by Langmuir isotherm model,indicating that the adsorption of RAN/NIZ was a monolayer coverage *** adsorption of RAN or NIZ by SAPc-1.1 and PAc-24.3 was strongly pH dependent,and high adsorption capacity could be observed under the condition of pH>pk_(a)+*** coexistence of hum.c.acid(HA)had no significant effect on the adsorption performance because RAN/NIZ may be coupled with HA and removed *** coexistence of anions had little effect on the adsorption *** study is expected to provide an alternative strategy for drinking water safety triggered by NDmA.

关键词： Adsorption NDmA Kinetics Superfine powdered activated carbon Intraparticle diffusion Drinking water

The moment map for the variety of associative algebras

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Science china mathematics 2025年第2期68卷 253-270页

作者： Hui zhang Zaili Yan School of mathematics Southeast UniversityNanjing 210096China School of mathematics and Statistics Ningbo UniversityNingbo 315211China

We consider the moment map m:PV_(n)→iu(n)for the action of GL(n)on V_(n)=■^(2)(c^(n))^(∗)■c^(n),and study the critical points of the functional Fn=||m||2:PV_(n)→***,we prove that[μ]∈PV_(n) is a critical point if and only if mμ=cμI+Dμfor some cμ∈R and Dμ∈Der(μ),where m([μ])=mμ||μ||*** we show that any algebraμadmits a Nikolayevsky derivationϕμwhich is unique up to automorphism,and if moreover,[μ]is a critical point of Fn,thenϕμ=−1 cμDμ.Secondly,we characterize the maxima and minima of the functional Fn:A_(n)→R,where A_(n) denotes the projectivization of the algebraic varieties of all the n-dimensional associative ***,for an arbitrary critical point[μ]of Fn:A_(n)→R,we obtain a description of the algebraic structure ofμ.Finally,we classify the critical points of Fn:A_(n)→R for n=2 and n=3,respectively.

关键词： moment map variety of associative algebras critical point

3D Printed chitosan Bioink Loaded with chrysin for Repairing Bone Defects

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chem.c.l Research in chinese Universities 2025年第1期41卷 155-164页

作者： zhang Hao TANG Wenshuo SUI Xin LI Lingfeng zhang Hongpu LI Yuran zhang Xueyi LIU Zhihui WANG Bowei Hospital of Stomatology Jilin UniversityChangchun130021P.R.China Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling Changchun130021P.R.China The Second Hospital of Jilin University Changchun130041P.R.China

This study aimed to investigate the potential of chrysin(c)to induce osteogenic differentiation of rat bone marrow mesenchymal stem.c.lls(Bm.c.)in ***(cS)was dissolved by repeated freeze-thawing of alkali/urea solutions,followed by co-printing of nano-hydroxyapatite(HAP)powders with different concentrations of c solutions(5,10,and 20µmol/L)compounded into cS *** rheological properties were modified with acetic acid/gelatin solution to construct c-cS-HAP(c-cS-H)composite scaffolds by extrusion printing *** characterization showed that the four groups of scaffolds had regularly interconnected porous structures with pore diameters of about 450–600µm,and the novel bioink exhibited shear-thinning properties,with the viscosity of the material decreasing in the shear rates range of 0.01–1000 s^(−1) and thus good *** osteogenic differentiation ability of Bm.c. was confirmed by the ccK-8 test,alkaline phosphatase(ALP)test,Alizarin Red staining(ARS)test,osteogenesis-related genes OcN,ALP,Runx 2,and bone morphogenetic protein-2(BmP-2)test,which showed a significant promotion of the osteogenic differentiation ability of Bm.c. with the increase of the content of *** above results indicate the potential of c-cS-H composite scaffolds in osteogenesis.

关键词： chrysin chitosan Bioscaffold 3D printing Hydroxyapatite

Evaluating the accuracy of earth rotation parameters based on the BDS observations

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Geodesy and Geodynam.c. 2025年第1期16卷 87-98页

作者： chenxiang Wang Pengfei zhang Tengxu zhang Ziyu Shen Jizhang Sang Wenbin Shen School of Geodesy and Geomatics Wuhan University Time and Frequency Geodesy center Wuhan University School of Resource Environmental Science and Engineering Hubei University of Science and Technology

The Bei Dou satellite system(BDS) has progressed with the full operationalization of the secondgeneration regional system(BDS-2) and the third-generation global system(BDS-3). This technology plays a crucial role in determining Earth Rotation Parameters(ERPs). In this study, we determine the ERPs based on the observations of BDS-2, BDS-3 and BDS-2+BDS-3, with the time spanning from August18, 2022, to August 18, 2023. The IERS EOP 20c04 series is used as a reference to evaluate the accuracy of the ERP estimates. We analyze the impact of different numbers of reference stations, polyhedron volumes, observation arc lengths, satellite types, and satellite systems on solving ERPs using BDS-2 and BDS-3 observation data provided by the International GNSS Service(IGS) stations. When selecting a specific satellite type, it is necessary to choose an appropriate observation arc length based on different numbers of reference stations while maximizing the volume of the formed polyhedron to achieve optimal efficiency and accuracy in parameter estimation. When both the number of reference stations and observation arc length are fixed, higher precision of the ERPs can be achieved using observations from mEO than mEO + IGSO and mEO + IGSO + GEO. moreover, when considering only IGSO and mEO satellites as options for analysis purposes, BDS-3 provides higher accuracy compared to BDS-2. In summary, when using BDS for ERP estimation and mEO satellite observations with the same observation arc length,selecting stations from reference stations with larger polyhedral volumes can significantly improve the efficiency and accuracy of parameter estimation.

关键词： Earth rotation parameters Polyhedron volume Observation arc length BDS-2 BDS-3

Effects of carbon content on the m.c.ostructure and tensile properties of a low-density steel

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International Journal of minerals,metallurgy and materials 2025年第2期32卷 391-401页

作者： Yongxuan Shang mingyu Fan Shuyong Jiang Zhongwu zhang Key Laboratory of Superlight materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China State Key Laboratory of metal material for marine Equipment and Application Iron&Steel Research Institute of Ansteel Group CorporationAnshan 114009China

carbon can change the phase components of low-density steels and influence the m.c.anical *** this study,a new method to control the carbon content and avoid the formation ofδ-ferrite by decarburization treatment was *** m.c.ostructural changes and m.c.anical characteristics with carbon content induced by decarburization were systematically ***-Jaoul(c-J)analysis was employed to examine the work hardening characteristics during the tensile *** decarburization by heat treatments,the carbon content within the austenite phase decreased,while mn and Al were almost unchanged;this made the steel with full austenite transform into the austenite and ferrite dual ***,(Ti,V)c carbides existed in both matrix phase and the mole fraction almost the *** addition,the formation of other carbides *** loss induced a decrease in strength due to the weakening of the carbon solid *** the steel with the single austinite,the deformation mode of austenite was the dislocation planar glide,resulting in the formation of *** the dual-phase steel,the deformation occurred by the dislocation planar glide of austenite first,with the increase in strain,the cross slip of ferrite took place,forming dislocation cells in *** the late stage of deformation,the work hardening of austinite increased rapidly,while that of ferrite increased slightly.

关键词： low-density steels carbon content decarburization strengthening m.c.anisms work hardening behavior

Atom.c.lly dispersed cu-based metal-organic framework directly for alkaline polymer electrolyte fuel cells

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chinese chem.c.l Letters 2025年第2期36卷 579-585页

作者： Wenbiao zhang Bolong Yang Zhonghua Xiang State Key Laboratory of Organic-Inorganic composites Beijing University of Chemical Technology Sungrow Hydrogen Sci.&Tech.co. Ltd.

Atom.c.lly dispersed cu-based single-metal-site catalysts （cu-N-c） have emerged as a frontier for electrocatalytic oxygen reduction reactions （ORR） because they can effectively optimize the D-band center of the cu active site and provide appropriate adsorption/desorption energy for oxygen-containing ***-organic frameworks （mOFs） show excellent prospects in many fields because of their structural regularity and designability,but their direct use for electrocatalysis has been rarely reported due to the low intrinsic ***,a mOF material （cu-TcNQ） with highly regular single-atom.c.pper active centers was successfully prepared using a solution chem.c.l reaction ***,cu-TcNQ and graphene oxide （GO） were directly self-assembled to form a cu-TcNQ/GO composite,which improved the conductivity of the catalyst while maintained the atom.c.lly precise *** resistivity of the cu-TcNQ/GO decreased by three orders of magnitude （1663.6–2.7 W/cm） compared with pure *** half-wave potential was as high as 0.92 V in 0.1 mol/L KOH,even better than that of commercial 20%Pt/*** alkaline polymer electrolyte fuel cells （APEFcs）,the open-circuit voltage and power density of cu-TcNQ/GO electrode reached 0.95 V and 320 m W/cm2,respectively,which suggests that cu-TcNQ/GO has a good potential for application as a cathode ORR catalyst.

关键词： Alkaline polymer electrolyte fuel cells cu-TcNQ/GO metal-organic frameworks Oxygen reduction reaction Single-metal-site catalysts

Hard rock tunnel boring m.c.ine penetration test as an indicator of chipping process efficiency

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Journal of Rock m.c.anics and Geotechnical Engineering 2017年第4期9卷 611-622页

作者： m.c. Villeneuve Department of Geological Sciences University of Canterbury Christchurch 8140 New Zealand

The transition from grinding to chipping can be observed in tunnel boring m.c.ine(TBm) penetration test data by plotting the penetration rate(distance/revolution) against the net cutter thrust(force per cutter) over the full range of penetration rates in the *** penetration test data to the geological and geom.c.anical characteristics of rock masses through which a penetration test is conducted provides the ability to reveal the efficiency of the chipping process in response to changing geological *** test data can also be used to identify stress-induced tunnel face *** research shows that the strength of the rock is an important parameter for controlling how m.c. net cutter thrust is required to transition from grinding to *** also shows that the geological characteristics of a rock will determine how efficient chipping occurs once it has *** particular,geological characteristics that lead to efficient fracture propagation,such as fabric and m.c. contents,will lead to efficient *** findings will enable a better correlation between TBm performance and geological conditions for use in TBm design,as a basis for contractual payments where penetration rate dominates the excavation cycle and in further academ.c.investigations into the TBm excavation process.

关键词： Penetration rate Grinding chipping Geological characteristics Face stability

concurrently Boosting Activity and Stability of Oxygen Reduction Reaction catalysts via Judiciously crafting Fe-mn Dual Atoms for Fuel cells

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Nano-m.c.o Letters 2025年第4期17卷 275-289页

作者： Lei zhang Yuchen Dong Lubing Li Yuchuan Shi Yan zhang Liting Wei chung-Li Dong Zhiqun Lin Jinzhan Su International Research center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an 710049People’s Republic of China Department of Physics Tamkang UniversityNew Taipei CityTaiwan 25137People’s Republic of China Department of chem.c.l and Biomolecular Engineering National University of SingaporeEngineering Drive 4Singapore 117585Singapore

The ability to unlock the interplay between the activity and stability of oxygen reduction reaction(ORR)represents an important endeavor toward creating robust ORR catalysts for efficient fuel ***,we report an effective strategy to concurrent enhance the activity and stability of ORR catalysts via constructing atom.c.lly dispersed Fe-mn dualmetal sites on N-doped carbon(denoted(Femn-DA)-N-c)for both anion-exchange membrane fuel cells(AEm.c.and proton exchange membrane fuel cells(PEm.c..The(Femn-DA)-N-c catalysts possess ample dual-metal atoms consisting of adjacent Fe-N_(4)and mn-N_(4)sites on the carbon surface,yielded via a facile doping-adsorption-pyrolysis *** introduction of mn carries several advantageous attributes:increasing the number of active sites,effectively anchoring Fe due to effective electron transfer to mn(revealed by X-ray absorption spectroscopy and density-functional theory(DFT),thus preventing the aggregation of Fe),and effectively circumventing the occurrence of Fenton reaction,thus reducing the consumption of ***(Femn-DA)-N-c catalysts showcase half-wave potentials of 0.92 and 0.82 V in 0.1 m KOH and 0.1 m HclO_(4),respectively,as well as outstanding *** manifested by DFT calculations,the introduction of mn affects the electronic structure of Fe,down-shifts the d-band Fe active center,accelerates the desorption of OH groups,and creates higher limiting *** AEm.c.and PEm.c.with(Femn-DA)-N-c as the cathode catalyst display high power densities of 1060 and 746 mW cm^(-2),respectively,underscoring their promising potential for practical *** study highlights the robustness of designing Fe-containing dual-atom ORR catalysts to promote both activity and stability for energy conversion and storage materials and devices.

关键词： Doping-adsorption-pyrolysis Dual-atom.c.talysts Oxygen reduction reaction Fuel cells