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Attaining synergetic equilibrium of electrical conductivity and tensile strength in GQDs@GN/Cu composites through multi-scale intragranular and intergranular reinforcements

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Rare Metals 2024年第1期43卷 366-379页

作者： Shuang-Yin Zhang Liang liu Rui bao Jian-hong Yi Sheng-Da Guo Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and TechnologyKunming 650093China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

The configuration and quality of reinforcements, as well as the robustness of interfacial bonding,holding a critical significance in determining the concurrence between electrical conductivity and mechanical strength in metal matrix composites. In this study, citric acid was employed as the precursor for synthesizing multiscale carbon nanomaterials(graphene quantum dots and graphene, abbreviated as GQDs and GN). The GQDs@GN/Cu composites were fabricated through a segmented ball milling process in conjunction with subsequent spark plasma sintering(SPS). The intragranular GQDs and intergranular GQDs@GN had synergistically reinforced Cu composites through Orowan strengthening, load transfer strengthening and refinement strengthening. Furthermore,the robust interface bonding between GQDs@GN and Cu effectively mitigated interfacial impedance stemming from electron-boundary scattering. The yield strength and ultimate tensile strength of the GQDs@GN/Cu composites were recorded as 270 and 314 MPa, respectively, representing an improvement of 92 and 28% over pure Cu, while maintaining electrical conductivity at a level comparable to that of pure Cu. This study advances the understanding of the possibility of realizing a synergistic compatibility between electrical conductivity and mechanical strength in Cu composites.

关键词： Cu matrix composites Interface bonding Mechanical property Graphene quantum dots(GQDs) Electrical conductivity

深空探测航天器推进系统永磁自锁式电磁阀设计及仿真

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阀门 2024年第4期 391-399,437页

作者：谢黄骏张明杨修东刘红宝魏东臧辉上海宇航系统工程研究所上海201109 宇航系统低温动力技术联合实验室上海201109

给出了一种应用于地月运输航天器的先导式高压、大流量永磁自锁式电磁阀(以下简称“自锁阀”)设计方案,对该自锁阀的电磁铁磁路设计进行了理论推导。对磁路中导磁材料铁钴钒软磁合金开展了不同热处理状态下的材料级试验,结果表明,两轮次... 详细信息

给出了一种应用于地月运输航天器的先导式高压、大流量永磁自锁式电磁阀(以下简称“自锁阀”)设计方案,对该自锁阀的电磁铁磁路设计进行了理论推导。对磁路中导磁材料铁钴钒软磁合金开展了不同热处理状态下的材料级试验,结果表明,两轮次880℃热处理条件可使材料获得较好的磁性能,其饱和磁感应强度达2.25 T以上,矫顽力低于150 A/m。根据使用工况对永磁体材料及O胶圈材料进行了选型和分析。采用有限元方法进行了磁回路静态及动态仿真,结果表明,-55~70℃工况下,永磁体对衔铁产生的静磁吸力在167~208 N之间,通电24 V条件下衔铁在70 ms内可完成全程动作。采用零维模型搭建主阀部分流通性能仿真系统,结果表明,来流压强为35 MPa氦气时,氦气流量0~350 g/s条件下,自锁阀主阀流阻低于0.35 MPa。

关键词：自锁阀推进系统软磁合金有限元仿真动态特性

New process for treating boron-bearing iron ore by flash reduction coupled with magnetic separation

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 473-484页

作者： Qipeng bao Lei Guo hong Yong Sohn Haibin Zuo Feng liu Yongliang Gao Zhancheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Department of Materials Science&Engineering University of UtahUtah 84112USA China ENFI Engineering Corporation Beijing 100038China

Boron is an important industrial raw material often sourced from minerals containing different compounds that cocrystallize,which makes it difficult to separate the mineral phases through conventional *** study proposed a new treatment called flash reduction-melting separation(FRMS)for boron-bearing iron *** this method,the concentrates were first flash-reduced at the temperature under which the particles melt,and the slag and the reduced iron phases disengaged at the particle *** reduc-tion and melting effects were achieved above 1550℃.The B_(2)O_(3) content in the separated slag was over 18wt%,and the B content in the iron was less than 0.03wt%.The proposed FRMS method was tested to investigate the effects of factors such as ore particle size and tem-perature on the reduction and melting steps with and without pre-reducing the raw *** mineral phase transformation and morphology evolution in the ore particles during FRMS were also comprehensively analyzed.

关键词： ludwigite boron-bearing iron concentrate flash reduction melting separation boron

Strong-coupling superconductivity with Tc above 70 K in Be-decorated monolayer T-graphene

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 99-105页

作者： liu Yang Peng-Fei liu Hao-Dong liu Ya-Ping Li Na Jiao hong-Yan Lu bao-Tian Wang Ping Zhang School of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Institute of Applied Physics and Computational Mathematics Beijing 100088China

Using first-principles calculations,we predict a new type of two-dimensional(2D)beryllium(Be)-decorated T-graphene named BeC_(2),where Be atoms are inserted into C–C bonds linking the carbon tetrarings of *** band structure shows that BeC_(2)is metallic,thus,the possible phonon-mediated superconductivity is explored based on the Eliashberg *** calculated electron-phonon coupling(EPC)constantλis up to 4.07,and the corresponding superconducting critical temperature(Tc)is 72.1 K,approaching the liquid nitrogen *** reason for the high Tc is the strong *** it is proved to be an anisotropic single-gap superconductor by analyzing the superconducting gap?kof BeC_(2).The electronic susceptibility calculation shows strong nesting effect in BeC_(2).Since rare 2D superconductors show such a strong EPC constantλwhich originates from the coupling between electrons in C-pzorbital and in-plane vibrations of Be and C atoms,the predicted BeC_(2)provides a new platform for investigating strong EPC 2D superconductor.

关键词： two-dimensional carbon-based superconductor electron-phonon coupling strong coupling high superconducting critical temperature

Risk Factors of Depression Screened by Two-Sample Mendelian Randomization Analysis:A Systematic Review

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Biomedical and Environmental Sciences 2024年第1期37卷 85-95页

作者： WANG Han Lin XUE Yan Feng CUI bao Qiu liu hong SHEN Xin Xin Shandong Provincial Research Center for Bioinformatic Engineering and Technique School of Life SciencesShandong University of TechnologyZibo 255049ShandongChina Shanxi Province Cancer Hospital/Shanxi Hospital Affiliated to Cancer Hospital Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical UniversityTaiyuan 030013ShanxiChina State Key Laboratory of Infectious Disease Prevention and Control National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China

Objective This study explored the potentially modifiable factors for depression and major depressive disorder(MDD)from the MR-Base database and further evaluated the associations between drug targets with *** We analyzed two-sample of Mendelian randomization(2SMR)using genetic variant depression(n=113,154)and MDD(n=208,811)from Genome-Wide Association Studies(GWAS).Separate calculations were performed with modifiable risk factors from MR-Base for 1,001 *** MR analysis was performed by screening drug targets with MDD in the DrugBank database to explore the therapeutic targets for *** variance weighted(IVW),fixed-effect inverse variance weighted(FE-IVW),MR-Egger,weighted median,and weighted mode were used for complementary *** The potential causal relationship between modifiable risk factors and depression contained 459 results for depression and 424 for ***,the associations between drug targets and MDD showed that SLC6A4,GRIN2A,GRIN2C,SCN10A,and IL1B expression are associated with an increased risk of *** contrast,ADRB1,CHRNA3,HTR3A,GSTP1,and GABRG2 genes are candidate protective factors against *** This study identified the risk factors causally associated with depression and MDD,and estimated 10 drug targets with significant impact on MDD,providing essential information for formulating strategies to prevent and treat depression.

关键词： Risk factors Drug targets Depression Major depressive disorder Two-sample Mendelian randomization

Remaining Useful Life Prediction Method for Multi-Component System Considering Maintenance:Subsea Christmas Tree System as A Case Study

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China Ocean Engineering 2024年第2期38卷 198-209页

作者： WU Qi-bing CAI bao-ping FAN hong-yan WANG Guan-nan RAO Xi GE Weifeng SHAO Xiao-yan liu Yong-hong CNOOC Safety Technology Services Co. Ltd.Tianjin 300456China College of Mechanical and Electronic Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Safety&Environmental Protection BranchTianjin 300456China

Maintenance is an important technical measure to maintain and restore the performance status of equipment and ensure the safety of the production process in industrial production,and is an indispensable part of prediction and health ***,most of the existing remaining useful life(RUL)prediction methods assume that there is no maintenance or only perfect maintenance during the whole life cycle;thus,the predicted RUL value of the system is obviously lower than its actual operating *** complex environment of the system further increases the difficulty of maintenance,and its maintenance nodes and maintenance degree are limited by the construction period and working conditions,which increases the difficulty of RUL *** RUL prediction method for a multi-omponent system based on the Wiener process considering maintenance is *** performance degradation model of components is established by a dynamic Bayesian network as the initial model,which solves the uncertainty of insufficient data *** on the experience of experts,the degree of degradation is divided according to Poisson process simulation random failure,and different maintenance strategies are used to estimate a variety of condition maintenance *** example of a subsea tree system is given to verify the effectiveness of the proposed method.

关键词： remaining useful life Wiener process dynamic Bayesian networks maintenance subsea Christmas tree system

A novel fused bi-macrocyclic host for sensitive detection of Cr_(2)O_(7)^(2-)based on enrichment effect

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Chinese Chemical Letters 2024年第7期35卷 291-295页

作者： Ting-Ting Huang Jin-Fa Chen Juan liu Tai-bao Wei hong Yao Bingbing Shi Qi Lin Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China Key Laboratory of Environment-Friendly Composite Materials of the State Ethnic Affairs Commission Gansu Provincial Biomass Function Composites Engineering Research CenterCollege of Chemical EngineeringNorthwest Minzu University(Northwest University for Nationalities)Lanzhou 730000China

Improving the highly selective and sensitive binding of chemosensor to target guest is always very *** order to solve this issue,herein,the enrichment effect was introduced into the design of chemosensor molecule.A novel bi-fused-macrocyclic host molecule BPN1 was synthesized by bridging a pillar[5]arene and a naphthalene diimide(NDI)group through hydrogen-bond-rich *** the BPN1,the naphthalimide side ring is outside the cavity of the pillar[5]*** addition,Cr(VI)greatly threat human health and the environment due to its severe toxicity,and it is very important to develop effective chemosensor for sensitive and selective detection of Cr_(2)O_(7)^(2-)or its ion *** this paper,the novel bi-fused-macrocyclic host molecule BPN1 can recognize Cr_(2)O_(7)^(2-)with high selectivity and *** mechanism of BPN1 recognition of Cr_(2)O_(7)^(2-)was studied through experiments and density functional theory(DFT),the results show that BPN1 could supply enrichment effect to bind Cr_(2)O_(7)^(2-)through multiple weak interactions such as hydrogen bonds and anion-π,and achieve highly sensitive and selective detection of Cr_(2)O_(7)^(2-).It is a significant and feasible strategy for improve high selectivity and sensitivity of host to specific objects by using the enrichment effect of fused bi-macrocyclic.

关键词： Pillararene Bi-macrocyclic Detection of Cr_(2)O_(7)^(2−) DFT The enrichment effect

A highly sensitive fluorescent probe RN-NA reveals peroxynitrite as a novel biomarker for primary open angle glaucoma

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 219-227页

作者： Bo Qin Yuan Lei Luo bao You-Jia Zhang Ke-Yin liu Yu-hong Chen Department of Ophthalmology&Visual Science Eye&ENT HospitalShanghai Medical CollegeFudan UniversityShanghai 200031China Key Laboratory of Myopia NHFPC(Fudan University)Shanghai Key Laboratory of Visual Impairment and Restoration(Fudan University)Shanghai 200031China State Key Laboratory of Biobased Material and Green Papermaking Key Laboratory of Pulp&Paper Science and Technology of Shandong Province/Ministry of EducationQilu University of TechnologyShandong Academy of SciencesJinan 250353Shandong ProvinceChina

AIM:To directly quantify peroxynitrite(ONOO-)using a highly sensitive fluorescence resonance energy transfer probe RN-NA,investigate the association between ONOOand primary open angle glaucoma(POAG),and clarify whether RN-NA could be used as a potential tool for POAG ***:Plasma and aqueous humor(AH)samples were collected from POAG patients(n=100,age:59.70±6.87y)and age-related cataract(ARC)patients(n=100,age:61.15±4.60y)admitted to our ***,RN-NA was used to detect ONOO-in plasma and AH samples,and the relationship between ONOO-level and POAG was analyzed using binary logistic ***,Pearson correlation analysis was applied to characterize the correlation of the levels of ONOO-with the patients’age,intraocular pressure(IOP),and mean deviation of visual field *** ONOO-scavenger MnTMPyP was employed to treat the 3-morpholinosyndnomine(SIN-1)-induced ocular hypertension in mice(n=7,6-8wk).Finally,the IOP and ONOO-in both eyes were measured 30min after the last drug ***:ONOO-levels of AH and plasma were significantly higher in the POAG group than in the ARC group(P<0.01).Additionally,ONOO-levels were closely correlated with POAG in a binary logistic regression analysis[odds ratio(OR)=1.008,95%confidence interval(CI):1.002-1.013,P<0.01 for AH;OR=1.004,95%CI:1.002-1.006,P<0.001 for plasma].Pearson correlation analysis showed that ONOO-levels in AH or plasma were positively associated with visual field defects(R=0.51,P<0.01 for AH;R=0.45,P<0.001 for plasma),and ONOO-levels in plasma and AH were correlated in the POAG group(R=0.69,P<0.001).However,administering MnTMPyP to mouse eyes reversed the elevated IOP caused by SIN-1(P<0.05).CONCLUSION:ONOO-levels in AH and plasma,detected by RN-NA,are significantly related to POAG and positively correlated with visual field defects in POAG ***,ONOO-is a potential biomarker of POAG,especially advanced ***,anti-nitration compounds may be novel ocular hypotens

关键词： peroxynitrite fluorescent probe RN-NA primary open angle glaucoma 3-morpholinosyndnomine

Fast and Adaptive Multi-Agent Planning under Collaborative Temporal Logic Tasks via Poset Products

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Research 2024年第2期2024卷 81-94页

作者： Zesen liu Meng Guo Weimin bao Zhongkui Li Deparment of Mechanics and Engineering Science College of EngineeringPeking UniversityBejing 0081 China Science and Technology Commission of China Aerospace Science and Technology Corporation Beijing 100048China

Efficient coordination and planning is essential for large-scale multi-agent systems that collaborate in a shared dynamic environment. Heuristic search methods or learning-based approaches often lack the guarantee on correctness and performance. Moreover, when the collaborative tasks contain both spatial and temporal requirements, e.g., as linear temporal logic (LTL) formulas, formal methods provide a verifiable framework for task planning. However, since the planning complexity grows exponentially with the number of agents and the length of the task formula, existing studies are mostly limited to small artificial cases. To address this issue, a new planning paradigm is proposed in this work for system-wide temporal task formulas that are released online and continually. It avoids two common bottlenecks in the traditional methods, i.e., (a) the direct translation of the complete task formula to the associated B點hi automaton and (b) the synchronized product between the B點hi automaton and the transition models of all agents. Instead, an adaptive planning algorithm is proposed, which computes the product of relaxed partially ordered sets (R-posets) on-the-fly and assigns these subtasks to the agents subject to the ordering constraints. It is shown that the first valid plan can be derived with a polynomial time and memory complexity with respect to the system size and the formula length. Our method can take into account task formulas with a length of more than 400 and a fleet with more than 400 agents, while most existing methods fail at the formula length of 25 within a reasonable duration. The proposed method is validated on large fleets of service robots in both simulation and hardware experiments.

关键词： hardware service system