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Manipulating mechanical properties of graphene/Al composites by an in-situ synthesized hybrid reinforcement strategy

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Journal of Materials Science & Technology 2022年第28期123卷 13-25页

作者： Lizhuang Yang bowen pu Xiang Zhang Junwei Sha Chunnian He Naiqin Zhao School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Key Laboratory of Advanced Ceramics and Machining Technology Ministry of EducationTianjin UniversityTianjin 300072China

The structural deterioration caused by the relatively weak out-of-plane bending stiffness and the chemically-active edge area of graphene limits its outperformance in strengthening for Al matrix composites(AMCs).Introducing one-dimensional(1D)carbon nanotubes(CNTs)to graphene/metal system is one of the promised strategies to complement the weakness of 2D graphene and make full use of the outstanding intrinsic properties of the both *** date,such synergistic strengthening and toughening mechanisms are largely *** this study,AMCs reinforced by a novel hybrid reinforcement,i.e.,graphene nanosheets decorated with Cu nanoparticles and CNTs(Cu@GNS-CNTs),are fabricated by an in-situ synthesis *** combined contrast experiments validated that the organically integrated reinforcing structure promotes the intrinsic load bearing capacity of GNS and the strain hardening capability of the Al matrix *** a result,the composites achieved excellent tensile strength and uniform elongation with almost no *** strengthening mechanism originated primarily from the hybrid reinforcement exhibits superior load-transfer,fracture inhibition and dislocation storage capability by controlling the interface reaction to construct an effective interface structure without damaging the *** work identifies a promising structural modification strategy for 2D materials and provides mechanistic insights into the synergistic strengthening effect of graphene/CNTs hybrid reinforcement.

关键词： Metal-matrix composites(MMCs) Mechanical properties Graphene Synergistic strengthening Interface

ZL702A铝合金双硬度峰值时效行为与微观组织分析

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热加工工艺 2024年第16期53卷 30-34页

作者：肖璐蒲博闻宋跃文杨晨帆王韬周海涛中北大学材料科学与工程学院山西太原030051 中国北方发动机研究所(天津) 天津300400 太原重型机械集团有限公司山西太原030024

将经490℃×4 h+500℃×6 h+520℃×8 h固溶、室温水介质淬火后的ZL702A铝合金在160、170℃两个温度下进行不同时间的时效处理,结合显微硬度法和透射电镜显微组织分析,研究ZL702A铝合金时效硬化行为与析出相演化规律之间的关联性。结果... 详细信息

将经490℃×4 h+500℃×6 h+520℃×8 h固溶、室温水介质淬火后的ZL702A铝合金在160、170℃两个温度下进行不同时间的时效处理,结合显微硬度法和透射电镜显微组织分析,研究ZL702A铝合金时效硬化行为与析出相演化规律之间的关联性。结果表明,ZL702A在160和170℃时效温度下的时效硬化曲线均表现出双硬度峰值的时效行为。这种时效强化现象归因于合金GP区向θ"、θ'、θ相的转变和Q'相粗化的共同作用。在160℃时效12 h对应的第一硬度峰值期,合金的硬度为114 HV,此时析出相对位错运动产生最大的阻碍作用,合金得到最理想的时效强化效果。

关键词：时效强化 ZL702A铝合金析出序列双硬度峰

基于水动力数值计算的小流域设计洪水模拟研究

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水电与抽水蓄能 2024年第4期10卷 14-19页

作者：王盼程龙蒲博文郭上渲歧雅菲中国电建集团西北勘测设计研究院有限公司陕西省西安市710065

基于水动力数值模拟方法,选择广州市花都区新街河流域作为研究区域,设计洪水计算分为天然和城市两类下垫面来考虑。采用MIKE11构建一维河道水动力模型,MIKE Urban构建管网水流模型,MIKE FLOOD耦合一维水动力模型与管网水流模型,推求新... 详细信息

基于水动力数值模拟方法,选择广州市花都区新街河流域作为研究区域,设计洪水计算分为天然和城市两类下垫面来考虑。采用MIKE11构建一维河道水动力模型,MIKE Urban构建管网水流模型,MIKE FLOOD耦合一维水动力模型与管网水流模型,推求新街河流域不同河道断面处的典型频率设计洪水。将耦合模型计算的设计洪水成果与传统水文分析方法计算的设计洪水成果进行对比,分析考虑了城市管网后流域洪水计算发生的变化;根据研究结果,对比综合单位线法和城市洪水耦合模型两种方法的计算结果,整体来说耦合模型计算的设计洪水成果偏大,符合一般地区城市化后洪水过程洪峰增大的变化规律;部分河涌耦合模型的设计洪水成果偏小,与径流在复杂的城市管网中的流动滞时、管径过流能力不足等原因有关。

关键词：水动力数值计算 MIKE 耦合模型城市设计洪水

Si-Assisted Solidification Path and Microstructure Control of 7075 Aluminum Alloy with Improved Mechanical Properties by Selective Laser Melting

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Acta Metallurgica Sinica(English Letters) 2022年第9期35卷 1424-1438页

作者： Junwei Sha Meixian Li Lizhuang Yang Xudong Rong bowen pu Dongdong Zhao Simi Sui Xiang Zhang Chunnian He Jianglin Lan Naiqin Zhao School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials Tianjin UniversityTianjin300350China Collaborative Innovation Center of Chemical Science and Engineering Tianjin300350China Key Laboratory of Advanced Ceramics and Machining Technology Ministry of EducationTianjin300350China Central Iron and Steel Research Institute(CISRI) Beijing100081China

The construction and application of traditional high-strength 7075 aluminum alloy(Al7075) through selective laser melting(SLM) are currently restricted by the serious hot cracking phenomenon. To address this critical issue, in this study, Si is employed to assist the SLM printing of high-strength Al7075. The laser energy density during SLM is optimized, and the eff ects of Si element on solidification path, relative density, microstructure and mechanical properties of Al7075 alloy are studied systematically. With the modified solidification path, laser energy density, and the dense microstructure with refined grain size and semi-continuous precipitates network at grain boundaries, which consists of fine Si, β-MgSi, Q-phase and θ-AlCu, the hot cracking phenomenon and mechanical properties are eff ectively improved. As a result, the tensile strength of the SLM-processed Si-modified Al7075 can reach 486 ± 3 MPa, with a high relative density of ~ 99.4%, a yield strength of 291 ± 8 MPa, fracture elongation of(6.4 ± 0.4)% and hardness of 162 ± 2(HV) at the laser energy density of 112.5 J/mm~3. The main strengthening mechanism with Si modification is demonstrated to be the synergetic enhancement of grain refinement, solution strengthening, load transfer, and dislocation strengthening. This work will inspire more new design of high-strength alloys through SLM.

关键词： Selective laser melting(SLM) 7075 aluminum alloy High-strength alloy Microstructure control Solidification path

Unravelling the nature of the active species as well as the Mn doping effect over gamma-Al_(2)O_(3) catalyst for eliminating AsH_(3) and PH_(3)

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Journal of Environmental Sciences 2024年第2期136卷 213-225页

作者： bowen Xu Jiaxin Qu Xueqian Wang Langlang Wang Yu pu Ping Ning Yibing Xie Yixing Ma Qiang Ma Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China School of Architecture and Civil Engineering Chengdu UniversityChengdu 610106China

To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by CuO-Al_(2)O_(3)in a reducing atmosphere under micro-oxygen conditions,Cu-Mn modifiedγ-Al_(2)O_(3)catalysts were *** characteristics of the catalysts showed that Mn reduced the crystallinity of the active CuO component,increased the number of oxygen vacancies and acidic sites on the catalyst surface,enhanced the mobility of surface oxygen,and the interaction between copper and manganese promoted the redox cycling ability of the catalysts and improved their oxidation performance,which increased the conversion frequency(TOF)by 2.54×10^(-2)to 3.07×10^(-2)sec^(-1).On the other hand,the introduction of Mn reduced the production of phosphate and As_(2)O_(3)on the catalyst surface by30.96%and 44.9%,which reduced the coverage and inerting of the active sites by phosphate and As_(2)O_(3),resulting in an 8 hr(6 hr)improvement in the stability of PH_(3)(AsH_(3))removal.

关键词： AsH_(3)-PH_(3)removal Oxygen activation Mn doping Stability enhancement

Application status and research progress of CO2 fracturing fluid in petroleum engineering: A brief review

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Petroleum 2024年第1期10卷 1-10页

作者： Jinzhou Zhao Tong Wu Wanfen pu Du Daijun Qingyuan Chen bowen Chen Jintao Li Yitao Huang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Shale Gas Research Institute of PetroChina Southwest Oil & Gas Field Company

This paper comprehensively reviews the application and research progress of CO2fracturing fluids in China, highlights the existing issues and puts forward suggestions for future development. Three types of fracturing fluid systems containing CO2, namely, CO2dry fracturing fluid, CO2energized fracturing fluid,and CO2foam fracturing fluid, are categorized based on the mass ratio and process difference between CO2, water, and treatment agents. Field applications in China reveal several problem to be resolved:（1）The application scope of CO2fracturing fluids is restricted to depleted reservoirs, re-fracturing of old wells, and medium-deep reservoirs with low formation pressure coefficients;（2） different types of CO2fracturing fluids require different processes and ground supporting equipment;（3） optimization of CO2compatibility, functionality, temperature and salt tolerance, as well as the cost of treatment agents is necessitated;（4） existing CO2fracturing fluid system fail to perform well with low friction, low filtration,and high sand-carrying capacity.（5） there lacks a targeted industry standard for evaluation of performance of CO2fracturing fluid system and treatment agents. Therefore, in order to meet the goals of CCUS-EOR, CCUS-EGR, or integration of fracturing, displacement and burial by CO2, efforts should be made in the aspects that followed, including in-depth investigation of the mechanism of CO2fracturing fluids, the adaptability and compatibility between existing equipment, different CO2fracturing fluid systems and processes, and construction of treatment agents, low-density proppants and highperformance systems of recyclability and industrial-grade. In addition, optimization of CO2fracturing fluid system based fracturing design is also crucial taking such related factors such as overall reservoir geological conditions, petrophysical properties, CO2transportation, and well site layout into consideration.

关键词： Reservoir reconstruction CO 2 fracturing fluid Fracturing fluid system Fracturing displacement burial integration

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多维度碳纳米相增强铝基复合材料研究进展

金属学报 2019年第1期55卷 1-15页

作者：赵乃勤刘兴海蒲博闻天津大学材料科学与工程学院天津300350

以铝基复合材料为代表的金属基复合材料,具有高的比强度、比模量及优异的导热、导电性能,在航空航天、汽车制造、机械电子及其它民用领域具有广泛的应用前景。近年来,碳纳米相作为复合材料的增强体凭借其优异的力学性能和物理性能以及... 详细信息

以铝基复合材料为代表的金属基复合材料,具有高的比强度、比模量及优异的导热、导电性能,在航空航天、汽车制造、机械电子及其它民用领域具有广泛的应用前景。近年来,碳纳米相作为复合材料的增强体凭借其优异的力学性能和物理性能以及自身结构特点,引起人们极大关注而成为铝基复合材料研究领域的新热点。本文从不同维度结构的碳纳米相(零维碳纳米洋葱、一维碳纳米管、二维石墨烯等)为增强相的角度,概述了这些碳纳米相增强铝基复合材料的制备方法及其在力学性能方面的研究进展,阐述了从单一相增强到多元多维度混杂增强的铝基复合材料在力学性能方面的优势,旨在阐明通过碳纳米相的结构设计和空间构筑实现高强韧性铝基复合材料的设计思路,并展望了高强韧轻金属基复合材料未来的研究趋势。

关键词：碳纳米材料铝基复合材料制备方法力学性能多维度

pu-erh tea partly improved liver cholesterol metabolism disorders in colitis mice via the gut-liver axis

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Food Science and Human Wellness 2024年

作者： Shanshan Hu Zhiyuan Lin Sibo Zhao bowen Zhang Liyong Luo Liang Zeng Chongqing Key Laboratory of Speciality Food Co-Built by Sichuan and Chongqing， Southwest University College of Food Science， Southwest University

pu-erh tea has been shown to reduce gut inflammation in DSS-induced mice. Also， we found abnormal liver cholesterol metabolism in dextran sulfate sodium (DSS)-induced mice. However， it’s not clear how pu-erh tea improves DSS-induced impaired liver cholesterol metabolism. Here， we established the DSS-induced model and clarified that DSS exacerbated gut inflammation accompanied by disorders of liver cholesterol metabolism. pu-erh tea reshaped gut microbes， limited gut oxidative stress and inflammation (NOX2/ROS/MyD88/NF-κB， 24.97%-52.89%)， reduced gut bile acid reabsorption (up-regulation of FXR/FGF15， 24.53%-55.91%)， and promoted liver bile acid synthesis (up-regulation of PPARα/CYP7A1， 34.65%-79.14%)， thereby partly restoring liver cholesterol metabolism (regulated FXR/SHP/SREBPs， 53.19%-95.40%). Altered bile acid metabolic profiles (increased chenodeoxycholic acid， ursodeoxycholic acid， lithocholic acid， etc.) may also improve liver cholesterol metabolism by altering gut and liver inflammation. Thus， gut microbial reshaping and altered bile acid metabolism may be key targets of pu-erh tea for improving DSS-induced liver cholesterol metabolism disorders via the gut-gut microbe-bile acid-liver axis.

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基于CPS的建筑环境下异构无线网络的选择算法

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科技广场 2015年第7期 111-116页

作者：溥博文马斌陈劲超沈阳建筑大学信息与控制工程学院辽宁沈阳110168

由于CPS是一个异构的分布式系统,由多种异构的网络通信构成。多种网络融合的研究是CPS网络进一步发展的重要任务。在建筑环境下,CPS为满足用户需求,提高通信服务质量(Qo S),需要选择一个最佳接入网络,否则会产生降低服务质量的不良后果... 详细信息

由于CPS是一个异构的分布式系统,由多种异构的网络通信构成。多种网络融合的研究是CPS网络进一步发展的重要任务。在建筑环境下,CPS为满足用户需求,提高通信服务质量(Qo S),需要选择一个最佳接入网络,否则会产生降低服务质量的不良后果。最佳接入网络的选择受几个因素的影响,面对传统算法考虑参数单一问题。本文提出一种利用层次分析,计算权重再进行加权平均计算决策的异构无线网络选择算法。通过仿真结果证明,利用改进的异构网络融合算法可以提高网络吞吐量,提升服务质量。

关键词：建筑环境 CPS 异构无线网络异构性 Qo S