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correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： peng li Meifeng cai Shengjun Miao yuan li yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in china were adopted,a newly defined characteristic parameter c_(ERp)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationsh.p.with *** is no remarkable correlation between the elastic modulus,poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationsh.p.between the rock quality designation(RQD)and *** maximum horizontal stress σ_(h) is a function of rock properties,showing a certain linear relationsh.p.with the c_(ERp)at the same *** addition,the overall change trend of σ_(h) determined by the established fuzzy identification method is to increase with the increase of c_(ERp).The fuzzy identification method also demonstrates a relatively detailed local relationsh.p.betweenσ_h and c_(ERp),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2p for lithium-sulfur batteries

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Journal of Energy chemistry 2025年第1期100卷 760-769页

作者： lin peng yu Bai hang li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of chemical power Source and Green catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

lithium-sulfur （li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2p by concurrently introducing B-doped atoms and p vacancies in Ni2p （Vp-B-Ni2p）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and p vacancies in Ni2p causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （lipSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and p vacancies in Ni2p selectively promotes li2S dissolution and nucleation ***,the li-S batteries with Vp-B-Ni2p-separators present outstanding rate ability of 777 m A h g-1at 5 c and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： lithium sulfur batteries

fluorinated poly(p-triphenylene isatin) anion exchange membranes based on hydrophilic hydroxyl side chain modulation for fuel cells

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Journal of Energy chemistry 2025年第1期100卷 702-709页

作者： Yiman Gu Yanchao Zhang Zhanyu li Yijia Lei Baozeng Sun Xiaoyu yu Zhe Wang college of chemistry and life Science Changchun University of Technology college of chemical Engineering Changchun University of Technology School of Materials Science and Engineering Changchun University of Technology Key Laboratory of Advanced functional polymer Membrane Materials of Jilin province

The development of alkaline fuel cells is moving forward at an accelerated pace,and the application of ether-free bonded polymers to anion exchange membranes （AEMs） has been widely ***,the question of the“trade-off”between AEM ionic conductivity and dimensional stability remains *** strategy of inducing microphase separation to improve the performance of AEM has attracted much attention recently,but the design of optimal molecular structures is still being ***,this work introduced different ratios of 3-bromo-1,1,1-trifluoroacetone （x=40,50,and 60） into the main chain of poly（p-terphenylene isatin）.Because fluorinated groups have excellent hydrophobicity,hydrophilic hydroxyl-containing side chains are introduced to jointly adjust the formation of phase separation *** results show that pTI-pTf50-NOh AEM with the appropriate fluorinated group ratio has the best ionic conductivity and alkali stability under the combined effect of *** has an ionic conductivity of 133.83 mS cm-1at 80°*** addition,the Oh-conductivity remains at 89%of the initial value at 80°c and 3 M KOh for 1056 h of *** cell polarization curve based on pTI-pTf50-NOh shows a power density of 734.76 mW cm-2at a current density of 1807.7 mA cm-2.

关键词： potassium hydroxide

palladium installed copper-organic.f.amework for c–c coupling reactions

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Science china chemistry 2025年

作者： yu-Mei Wang Mei-Xia Tao Kai-Ming Mo Xu chen Shu-hua Zhong Elena S Shubina Guo-hong Ning Dan li college of chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.N.Nesmeyanov Institute of Organoelement compounds Russian Academy of Sciences

The formation of c–c bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic.f.ameworks(cMOfs) based on copper cyclic trinuclear units(cu-cTUs). By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical c–c coupling reactions, including c–h arylation and Sonogashira cross-coupling. The resulting JNM-7-pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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Double heterogeneous structures induced excellent strength-ductility synergy in Ni_(40)co_(30)cr_(20)Al_(5)Ti_(5) medium-entropy alloy

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Journal of Materials Science & Technology 2024年第14期181卷 176-188页

作者： A.X.li X.S.liu R.li S.B.yu M.h.Jiang J.S.Zhang c.N.che D.huang p.f.yu G.li State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

The application of single-phase face-centered cubic.f.c)medium entropy alloys(MEAs)in the engi-neering industry is often hindered by the challenge of insufficient *** this study,a novel non-equiatomic ratio Ni_(40)co_(30)cr_(20)Al_(5)Ti_(5)MEA was successfully *** the well-designed mechan-ical heat treatment processing,we introduced a heterogeneous grain structure comprising 67.4%fine grain and 32.6%coarse ***,heterogeneous size L12 phases consisting of 18.7%submicron precip-itates and 11.7%nano-sized precipitates,were incorporated into the *** tests conducted at room temperature revealed that the double heterogeneous structure alloy demonstrated remarkable strength–ductility *** exhibited a yield strength of 1200 Mpa,an ultimate tensile strength of 1560 Mpa and a total elongation of 33.6%.The exceptional strength of the alloy can be primarily attributed to heteroge-neous deformation induced strengthening,grain boundary strengthening and precipitation *** excellent ductility is mainly attributed to the high-density stacking faults and Lomer–cottrell *** study not only contributes to the clarification of the strengthening and deformation mechanism of double heterogeneous structure alloys but also provides an effective strategy for the development of high.p.rformance alloys with high strength and ductility.

关键词： Medium entropy alloy Double heterogeneous structure hDI strengthening Remarkable tensile properties

The Kirkendall effect on erosion resistance of chrome-coated 25cr3Mo2WNiV and 30SiMn2MoV gun barrel steels

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Journal of Materials Science & Technology 2024年第10期177卷 246-255页

作者： c.h.Dou p.f.Jin c.Z.Wang J.J.li c.Zhang J.f.huang c.Zhang Key Laboratory for Advanced Materials processing State State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China National Joint Engineering Research center for Abrasion control and Molding of Metal Materials School of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang 471003China

This study aimed to investigate the erosion behavior and mechanism of a newly developed 25cr3Mo2WNiV steel with a chrome coating using promoted ignition combustion *** erosion threshold pressure and temperature of the chrome-coated 25cr3Mo2WNiV steel were determined to be 0.2 Mpa and 254.3 K higher than those of traditional chrome-coated 30SiMn2MoV ***,Kirkendall voids and inter-diffusion between the cr coating and matrix were first observed before *** improved erosion resistance of the chrome-coated 25cr3Mo2WNiV steel was attributed to the suppression of the Kirkendall effect,which minimized heat generation at the cr/matrix interface by pre-venting oxygen diffusion and reducing oxygen affinity.

关键词： Erosion resistance Kirkendall effect cr coating Gun steel

constructing Donor–Acceptor‑linked c.f. Electrolytes to Regulate Electron Density and Accelerate the li^(+)Migration in Quasi‑Solid‑State Battery

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Nano-Micro Letters 2025年第1期17卷 456-471页

作者： Genfu Zhao hang Ma conghui Zhang Yongxin Yang Shuyuan yu haiye Zhu Yongjiang Sun hong Guo School of Materials and Energy International Joint Research Center for Advanced Energy Materials of Yunnan ProvinceYunnan UniversityKunming 650091People’s Republic of China yunnan yuntianhua co. LtdR&D CenterKunming 650228People’s Republic of China Southwest United Graduate School Kunming 650091People’s Republic of China

Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective li^(+)transportation and conduction in solid-state li metal *** study reports a high.p.rformance solid-state electrolyte thorough D–A-linked covalent organic.f.ameworks(c.f.)based on intramolecular charge transfer *** other reported c.f.ased solid-state electrolyte,the developed concept with D–A-linked c.f. not only achieves electronic modulation to promote highly-selective li^(+)migration and inhibit li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state li metal *** introduced strong electronegativity f-based ligand in c.f.electrolyte results in highlyselective li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in li metal symmetric cell and high-capacity retention in li/lifepO_(4)cell(90.8%for 300 cycles at 5c)than substituted c-and N-based *** is ascribed to outstanding D–A interaction between donor porphyrin and acceptor f atoms,which effectively expedites electron transferring from porphyrin to f-based ligand and enhances li^(+)***,we anticipate that this work creates insight into the strategy for accelerating li^(+)conduction in high.p.rformance solid-state li metal batteries through D–A system.

关键词： Electronic modulation engineering Donor-acceptor-linked covalent organic.f.ameworks Quasi-solid-state li metal battery

Excellent strength-ductility combination in co_(36)cr_(15)fe_(18)Ni_(18)Al_(8)Ti_(4)Mo_(1)multi-principal element alloys by dual-morphology B2 precipitates strengthening

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Journal of Materials Science & Technology 2023年第3期134卷 60-66页

作者： X.S.liu R.li X.f.fan Q.Q.liu X.Tong A.X.li S.Xu h.Yang S.B.yu M.h.Jiang c.huo p.f.yu M.T.Dove G.li State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China college of computer Science Sichuan UniversityChengdu 610065China School of physical and chemical Sciences Queen Mary University of LondonMile End RoadLondon E14NSUnited Kingdom School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China

precipitation strengthening provides one of the most widely-used mechanisms for strengthen-ing multi-principal-element alloys(MpEAs).here,we report dual-morphology B2 precipitates in co_(36)cr_(15)fe_(18)Ni_(18)Al_(8)Ti_(4)Mo_(1)MpEA obtained by thermo-mechanical *** microscopy charac-terization reveals that the dual-morphology B2 precipitates are either recrystallized B2 particles formed at the grain boundaries or triple junctions with recrystallization process,or rod-like within the non-recrystallized fcc *** dual-morphology B2 precipitates enhance the yield strength and ultimate tensile strength up to 1120 Mpa and 1480 Mpa,*** work suggests the mechanical proper-ties of the alloy can be optimized by B2 precipitation strengthening to meet the needs of engineering applications.

关键词： Multi-principal element alloys B2 precipitates heterogeneous nucleation precipitation strengthening

Effect of scanning strategy on grain structure and crystallographic texture of Inconel 718 processed by selective laser melting

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Journal of Materials Science & Technology 2018年第10期34卷 1799-1804页

作者： h.Y. Wan Z.J. Zhou c.p. li G.f. chen G.p. Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China Materials & Manufacturing Qualification Group Corporate Technology Siemens Ltd. Beijing 100102 China

Two types of scanning strategies were adopted to study the effect of scanning strategy on grain structure and crystallographic texture of selective laser melted （SLM） Inconel 718. The results show that bidirec-tional scanning without and with a 90°-rotation for every layer produced the bimodal grain structure and the directional columnar grain structure, respectively. controlling the heat flux direction between the successive layers via scanning strategy enabled the formation of such different grain structures. fur-thermore, when the 90°-rotation was applied, the competitive grain growth mechanism became more pronounced and the strong cube texture developed.

关键词： Selective laser melting Additive manufacturing Scanning strategy Texture Grain structure