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Journal of Materials Science & Technology 2019年第12期35卷 2840-2850页

作者： junfeng gu Ji Zou Peiyan Ma Hao Wang Jinyong Zhang Weimin Wang Zhengyi Fu State Key Laboratory of Advanced Technology for Materials Synthesis and Processing.Wuhan University of Technology Wuhan430070China School of Metallurgy and Materials University of BirminghamB152TTBirminghamUK School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan.430070China

Carbide boronizing is a promising approach to obtain fine grained boron carbide based ceramics with improved mechanical properties. In this work, reaction process, microstructural characteristics and mechanical properties of BxC-TaB2(x = 3.7, 4.9, 7.1) ceramics were comprehensively investigated via this method. Dense BxC-TaB2 ceramics with refined microstructure were obtained from submicro tantalum carbide and boron powder mixtures at 1800℃/50 MPa/5 min by spark plasma sintering. The stoichiometry of boron carbide was determined from lattice parameters and Raman shift. It was found that uniformly distributed TaB2 grains in the BxC matrix is favor of the densification process and restricting grain ***, planar defects with high density were observed from the as-formed B7.1 C grains and transient stress was considered to contribute to the densification involved with plastic deformation. Microstructural observations indicate the dissolution of oxygen in the TaB2 lattice and most of the B7.1 C/TaB2 phase boundaries were clean. Owing to the highly faulted structure and finer grain size, as-obtained BxC-TaB2 ceramics exhibit high Vickers hardness(33.3–34.4 GPa at 9.8 N) and relatively high flexural strength ranging from 440 to 502 MPa.

关键词： Boron carbide Reaction sintering Densification Microstructure Mechanical properties

Braided river and distribution patterns of sand bodies of Jurassic Badaowan formation in Block T13 of Junggar basin

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Mining Science and Technology 2010年第3期20卷 446-452页

作者： SUN Xiaofang JIN Zhenkui WANG Zhaofeng HUANG Xiaoping gu junfeng Faculty of Information & Resource China University of Petroleum Beijing 102249 China Exploration and Exploitation Institute of Xinjiang Oilfield Company Karamayi 834003 China

In order to determine the planar and volume distribution of sand bodies of the Jurassic Badaowan formation in Block T13 of Junggar basin,we used analysis of field outcrop and 3D seismic data,which play an essential role in areas of sparse well *** describe sedimentary facies characteristics,sand body planforms,width and connectivity patterns of sand bodies,and vertical associations and successions by acoustic impedance inversion technology and sedimentological *** of our study show braided fluvial strata deposits in the Jurassic Badaowan *** sand body is approximately lenticular in *** width of each sand body falls in the range 100～800 m,with most between 200 and 400 *** sand bodies vary in thickness from 4 to 13 m,with most below 9 *** width/thickness ratios lie in the range 20～*** connectivity of braided fluvial channel sand bodies is controlled by changes of accommodation *** fining-upward sedimentary cycle of base-level rise is recognized in Badaowan formation,representing an upward rise of base *** connectivity of sand bodies was found to be greatest in the early stage of base-level rise,becoming progressively worse with increasing base-level rise.

关键词： Block T13 Badaowan formation braided river sand body distribution patterns

Self-supported high-entropy alloy electrocatalyst for highly efficient H_(2) evolution in acid condition

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Journal of Materiomics 2020年第4期6卷 736-742页

作者： Peiyan Ma Mingming Zhao Long Zhang Heng Wang junfeng gu Yuchen Sun Wei Ji Zhengyi Fu School of Chemistry Chemical Engineering and Life scienceWuhan University of TechnologyWuhan CityHubei ProvincePR China State Key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan CityHubei ProvincePR China Engineering Research Center of Environmental Materials and Membrane Technology School of Materials Science and EngineeringWuhan Institute of TechnologyWuhan CityHubei ProvincePR China

Developing non-precious catalysts as Pt substitutes for electrochemical hydrogen evolution reaction(HER)with superior stability in acidic electrolyte is of critical importance for large-scale,low-cost hydrogen production from ***,we report a CoCrFeNiAl high-entropy alloy(HEA)electrocatalyst with self-supported structure synthesized by mechanical alloying and spark plasma sintering(SPS)*** HEA after HF treatment and in situ electrochemical activation for 4000 cycles of cyclic voltammetry(HF-HEAa2)presents favourable activity with overpotential of 73 mV to reach a current density of 10 mA cm^(2) and a Tafel slope of 39.7 mV dec*** alloy effect of Al/Cr with Co/Fe/Ni at atomic level,high-temperature crystallization,as well as consolidation by SPS endow CoCrFeNiAl HEA with high stability in 0.5 M H2SO4 *** superior performance of HF-HEAa2 is related with the presence of metal hydroxides/oxides groups on HEA.

关键词： loy Hydrogen evolution reaction Electrocatalysts Acidic electrolyte Stability

Depositional characteristics and petroleum geological significance of wetland

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Petroleum Science 2009年第4期6卷 347-353页

作者： Jin Zhenkui gu junfeng Su Nina Wang Zhaofeng Huang Xiaoping State Key Laboratory of Hydrocarbon Resources and Exploration China University of PetroleumBeijing 102249China Research Institute of Petroleum Exploration and Development Xinjiang Oilfield CompanyPetroChinaKaramayXinjiang 834000China

Wetland is a new type of sedimentary facies proposed for the first time in this paper. It is a type of sedimentary environment, transitional between land facies and water (sea or lake) facies. In this paper, wetland is redefined as “a type of sedimentary environments whose ground surface is flat and wet throughout the year, which may be covered with very shallow water (less than 2 m deep), and is covered with lush plant growth”. Wetland is reclassified into two types, swamp wetland (swamp in brief) and wet plain wetland (wet plain in brief). Swamp deposits are coal, while wet plain deposits are dark colored mudstones or silty mudstones rich in plant fossils and carbon debris. The deposits of wet plain are different from those of lake and floodplain in the abundance of plant fossils, color, resistivity well logging curve, and other sedimentary characteristics. In boreholes, resistivity logging can be used to distinguish between wet plain mudstones and lake mudstones. Understanding the sedimentary characteristics of wet plain wetland can help to identify wet plain deposits which were formerly classified as floodplain or lake deposits. This will help to reconstruct the palaeogeography and to understand the history of basin and climate evolution accurately, and is especially important in evaluation of the hydrocarbon generating potential of a basin. With the Jurassic Sangonghe Formation of the Yanqi Basin as an example, the identification characteristics of wetland are described.

关键词： Wetland wet plain Yanqi Basin Sangonghe Formation of Jurassic braided river delta

静电纺丝制备高强度聚偏氟乙烯锂离子电池隔膜

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高分子材料科学与工程 2019年第3期35卷 148-155页

作者：龚文正谷俊峰阮诗伦申长雨大连理工大学材料科学与工程学院大连理工大学工程力学系工业装备结构分析国家重点实验室辽宁大连116024

静电纺丝聚偏氟乙烯(PVDF)纤维膜具有比表面积大、孔隙率高和电解液润湿性好等优点,但聚合物纤维仅靠简单的搭接形成膜,相互之间的黏接力较弱,因而静电纺丝纤维膜难以满足隔膜在锂离子电池装配过程中的受力要求。文中通过增大静电纺丝... 详细信息

静电纺丝聚偏氟乙烯(PVDF)纤维膜具有比表面积大、孔隙率高和电解液润湿性好等优点,但聚合物纤维仅靠简单的搭接形成膜,相互之间的黏接力较弱,因而静电纺丝纤维膜难以满足隔膜在锂离子电池装配过程中的受力要求。文中通过增大静电纺丝接收装置的转速来提高PVDF纤维的取向度,使得纤维膜沿纤维取向方向的力学强度有效增强,然后在PVDF熔点温度以下将取向纤维膜90°交叉叠加后进行热压处理,得到纵、横2个方向拉伸强度均达到15.6 MPa的新型锂离子电池隔膜;交流阻抗测试表明热压处理后的PVDF取向膜离子电导率达到1.52 mS/cm,远高于商业PP隔膜,同时隔膜与锂电极之间的界面电阻也小于PP隔膜;充放电循环测试表明,使用热压PVDF取向膜装配的锂离子电池在0.2 C倍率循环50次之后,放电容量仍能达到140.1 mA·h/g,同时电池还展现出良好的大倍率放电性能。

关键词：静电纺丝聚偏氟乙烯锂离子电池隔膜力学性能

Dense and pure high-entropy metal diboride ceramics sintered from self-synthesized powders via boro/carbothermal reduction approach

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Science China Materials 2019年第12期62卷 1898-1909页

作者： junfeng gu Ji Zou Shi-Kuan Sun Hao Wang Su-Yang Yu Jinyong Zhang Weimin Wangand Zhengyi Fu State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China School of Metallurgy and Materials University of BirminghamBirmingham B152TTUnited Kingdom Department of Materials Science and Engineering University of SheffieldSheffield SI 3JDUnited Kingdom

Equimolar quinary diboride powders,with nominal composition of(Ti0.2 Hf0.2 Zr0.2 Nb0.2 Ta0.2)B2,were synthesized by boro/carbothermal reduction(BCTR)of oxide mixtures(MOx,M=Ti,Hf,Zr,Nb and Ta)using B4 C as source of B and C in *** adjusting the B4 C/MOxratios,diboride mixtures without detectable MOxwere obtained at 1600℃,while high-entropy diboride(HEB)powders with particle size of<1μm was obtained at 1800℃.The phase,morphology and solid solution evolution process of the HEB powders during the BCTR process were comprehensively *** X-ray diffraction pattern indicated the powders synthesized at 1800℃ were in a single-phase Al B2 structure,elemental mappings showed that(Ta,Ti)-rich and(Zr,Nb)-rich solid solution coexisted in the HEB *** distribution of niobium and zirconium atoms in HEB was unable to reach uniform until the HEB powders were spark plasma sintered at 2000°C.(Ti0.2 Hf0.2 Zr0.2 Nb0.2 Ta0.2)B2 ceramics with a relative density of 97.9%were obtained after spark plasma sintering the HEB powders at 2050℃ under 50 *** grain growth was found in this composition when the sintering temperature was increased from 2000 to 2050℃,and the averaged grain size increased from 6.67 to 41.2μ*** ceramics sintered at 2000℃ had a Vickers hardness of 22.44±0.56 GPa(under a load of 1 kg),a Young’s modulus of^500 GPa and a fracture toughness of 2.83±0.15 MPa m1/*** is the first report for obtaining high density HEB ceramics without residual oxide phase,benefiting from the high quality HEB powders obtained.

关键词： ultra-high temperature ceramics high-entropy borides solid solution rapid grain growth powder synthesis

Hydroxylated high-entropy alloy as highly efficient catalyst for electrochemical oxygen evolution reaction

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Science China Materials 2020年第12期63卷 2613-2619页

作者： Peiyan Ma Shichao Zhang Mutian Zhang junfeng gu Long Zhang Yuchen Sun Wei Ji Zhengyi Fu School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070China State Key Lab of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Oxygen evolution reaction(OER),a half reaction involved in electrochemical water splitting,CO2 reduction,and metal–air batteries,restricts the efficiency of these energy conversion systems due to sluggish reaction kinetics[1,2].To accelerate OER,highly efficient electrocatalysts are ***,large-scale applications of the normally used OER catalysts(***2 and IrO2)are hampered by their instability and low *** is highly desirable to develop earth-abundant catalysts with low cost,high activity and long-term ***(Ni,Fe)(oxy)hydroxides(Co(Ni)-(O)OH)have emerged as promising OER catalysts in recent years[3].

关键词： Tafel斜率高熵合金电催化剂电化学活性羟基化超电势电化学活化高效催化剂

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AVO技术在气藏预测中的应用

科技导报 2009年第6期27卷 43-47页

作者：顾军锋金振奎中国石油大学(北京)资源与信息学院北京102249

AVO技术以弹性理论为基础,对地震反射振幅随炮检距的变化特征进行研究,以达到利用地震反射振幅信息检测油气的目的。分析了AVO反演的技术流程,对无实测横波资料的井采用优化Xu-White模型进行横波预测,并对叠前地震资料利用蓝色滤波技术... 详细信息

AVO技术以弹性理论为基础,对地震反射振幅随炮检距的变化特征进行研究,以达到利用地震反射振幅信息检测油气的目的。分析了AVO反演的技术流程,对无实测横波资料的井采用优化Xu-White模型进行横波预测,并对叠前地震资料利用蓝色滤波技术进行拓频处理。叠前AVO反演方法选择同步反演法,同时反演得到纵波阻抗、横波阻抗及密度数据体,在此基础上提取出各种弹性参数,结合区域地质和测井解释气层标准,达到岩性及气层预测的目的。通过将该技术在中国东部某区块的应用,证明所预测的气层厚度与测井解释结果的相对误差小于4%,预测精度较高。

关键词： AVO技术优化Xu—White模型蓝色滤波同步反演气层预测

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云计算环境下网络安全技术的应用现状及对策

移动信息 2024年第3期46卷 124-126页

作者：顾军峰中国电信上海分公司上海201199

随着云计算技术的发展,许多新的安全挑战也随之而来,其中包括病毒攻击和DDoS攻击。为了确保云计算技术的安全和稳定性,必须加强技术水平和服务质量,以减少安全事件的发生概率。文中旨在深入探讨云计算环境下的网络安全技术应用现状及其... 详细信息

随着云计算技术的发展,许多新的安全挑战也随之而来,其中包括病毒攻击和DDoS攻击。为了确保云计算技术的安全和稳定性,必须加强技术水平和服务质量,以减少安全事件的发生概率。文中旨在深入探讨云计算环境下的网络安全技术应用现状及其存在的风险,并提出相对应的防范策略,为提升中国云计算机环境下网络的可信度和安全性提出有效的参考。

关键词：云计算环境网络安全技术现状和策略

熔融沉积3D打印材料粘接强度及模量预测研究

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化工学报 2019年第7期70卷 2727-2736,F0004页

作者：张黎王新宇李征谷俊峰阮诗伦申长雨大连理工大学工程力学系辽宁大连116024 俄亥俄州立大学化学及生物分子工程系美国俄亥俄州43210-1350 大连理工大学工业装备结构分析国家重点实验室辽宁大连116024

主要介绍了一种用于预测熔融沉积模型(FDM)层间粘接强度的扩散修复模型。根据流变数据确定温度相关扩散模型,基于一维瞬态热分析预测FDM部件层间的扩散。将温度历史上的扩散系数对时间积分得到界面分子总扩散,进而得到层间粘接强度预测... 详细信息

主要介绍了一种用于预测熔融沉积模型(FDM)层间粘接强度的扩散修复模型。根据流变数据确定温度相关扩散模型,基于一维瞬态热分析预测FDM部件层间的扩散。将温度历史上的扩散系数对时间积分得到界面分子总扩散,进而得到层间粘接强度预测模型。结果表明:不同打印条件下预测结果与测得的粘合强度结果的吻合度较好,且该模型经修正后也适用于FDM部件弹性模量的预测。通过三点弯曲实验与数值模拟的结果对比,验证了粘接强度及模量预测模型的可用性。因此,可以作为FDM打印件承载性能预测的有效模型。

关键词：聚合物熔融沉积成型层间粘接性能预测扩散数值模拟