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Journal of Systems Science & Complexity 2022年第1期35卷 159-178页

作者： XING Ruitao XIAO Min zhang yuezhong QIU Jianlong College of Automation and College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210003China School of Automation and Electrical Engineering Linyi UniversityLinyi 276000China

Up till the present moment,researchers have always featured the single-ring neural *** investigations,however,disregard the link between rings in neural *** paper highlights a high-dimensional double-ring neural network model with multiple time *** neural network has two rings of a shared node,where one ring has n neurons and the other has m+1 *** utilizing the sum of time delays as the bifurcation parameter,the method of Coates’flow graph is applied to obtain the relevant characteristic *** stability of the neural network model with bicyclic structure is discussed by dissecting the characteristic equation,and the critical value of Hopf bifurcation is *** effect of the sum of time delays and the number of neurons on the stability of the model is *** validity of the theory can be verified by numerical simulations.

关键词： Coates’flow graph high-dimensional Hopf bifurcation stability

Microstructures,corrosion behavior and mechanical properties of as-cast Mg-6Zn-2X(Fe/Cu/Ni)alloys for plugging tool applications

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 697-711页

作者： Baosheng Liu Jiali Wei Shaohua zhang yuezhong zhang Pengpeng Wu Daqing Fang Guorui Ma School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Intelligent Equipment Research and Development Center Zhuhai Institute of Advanced Technology Chinese Academy of SciencesZhuhai 519080China Advanced Materials Research Institute Zhuhai Dingmei Medical Technology Co.Ltd.Zhuhai 519000China

Mg-6Zn-2X(Fe/Cu/Ni)alloys were prepared through semi-continuous casting,with the aim of identifying a degradable magnesium(Mg)alloy suitable for use in fracturing balls.A comparative analysis was conducted to assess the impacts of adding Cu and Ni,which result in finer grains and the formation of galvanic corrosion *** electronic microscopy examination revealed that precipitated phases concentrated at grain boundaries,forming a semi-continuous network structure that facilitated corrosion penetration in Mg-6Zn-2Cu and Mg-6Zn-2Ni *** corrosion was observed in Mg-6Zn-2Fe,while galvanic corrosion was identified as the primary mechanism in Mg-6Zn-2Cu and Mg-6Zn-2Ni *** the tests,the Mg-6Zn-2Ni alloy exhibited the highest corrosion rate(approximately 932.9 mm/a)due to its significant potential *** testing showed that Mg-6Zn-2Ni alloy possessed suitable ultimate compressive strength,making it a potential candidate material for degradable fracturing balls,effectively addressing the challenges of balancing strength and degradation rate in fracturing applications.

关键词： magnesium alloys microstructure micro-galvanic corrosion mechanical properties

Cenozoic Stratigraphy Deformation History in the Central and Eastern of Qaidam Basin by the Balance Section Restoration and its Implication

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Acta Geologica Sinica(English Edition) 2009年第2期83卷 359-371页

作者： LIU Dongliang FANG Xiaomin GAO Junping WANG Yadong zhang Weilin MIAO Yunfa LIU Yongqian zhang yuezhong Center of Basin Resources and Environment Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Graduate School Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Western China＇s Environmental Systems Ministry of Education of China College of Resources and Environment Lanzhou University Lanzhou 730000 China Research Institute of Petroleum Exploration and Development PetroChina Qinghai Oilfield Company Dunhuang Gansu 736202 China

The Qaidam Basin, located in the northern margin of the Qinghai-Tibet Plateau, is a large Mesozoic-Cenozoic basin, and bears huge thick Cenozoic strata. The geologic events of the Indian- Eurasian plate-plate collision since -55 Ma have been well recorded. Based on the latest progress in high-resolution stratigraphy, a technique of balanced section was applied to six pieces of northeast- southwest geologic seismic profiles in the central and eastern of the Qaidam Basin to reconstruct the crustal shortening deformation history during the Cenozoic collision. The results show that the Qaidam Basin began to shorten deformation nearly synchronous to the early collision, manifesting as a weak compression, the deformation increased significantly during the Middle and Late Eocene, and then weakened slightly and began to accelerate rapidly since the Late Miocene, especially since the Quaternary, reflecting this powerful compressional deformation and rapid uplift of the northern Tibetan Plateau around the Qaidam Basin.

关键词： balance section shortening deformation history Qaidam Basin uplift of the TibetanPlateau

Effects of Cu on Microstructure and Corrosion Behaviour of Hot-Rolled Mg-3Zn-1Y Alloys

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稀有金属材料与工程 2024年第10期53卷 2794-2804页

作者： zhang yuezhong Chen Xiaoting Shen Jing Wu Pengpeng zhang Shaohua Liu Baosheng College of Chemical Engineering and Technology Taiyuan University of Science and TechnologyTaiyuan 030024China College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China

The microstructure and corrosion behaviour of hot-rolled Mg-3Zn-1Y-xCu alloys(x=0,1,3,5,wt%)were *** show that all Mg-3Zn-1Y-xCu alloys mainly consist ofα-Mg matrix and Mg_(3)Zn_(6)Y *** addition of Cu element promotes the formation of MgZnCu phase,and the amount of MgZnCu phase is increased with the increase in Cu *** and immersion test results show that the corrosion resistance of Mg-3Zn-1Y-xCu alloys is deteriorated after Cu addition,which can be attributed to the influence of the microstructure of alloys and the properties of the formed corrosion product *** MgZnCu phase with high electrochemical potential accelerates the micro-galvanic corrosion as strong cathodic sites,and the decreased protection effect of the corrosion product film results from the variation in PBR value of the related compounds.

关键词： corrosion behaviour magnesium alloy microstructure MgZnCu phase corrosion product

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一种高精度的BDS/INS紧耦合测姿算法

电讯技术 2017年第2期57卷 151-156页

作者：蒋青张跃仲重庆邮电大学移动通信技术重庆市重点实验室重庆400065

针对"北斗"卫星姿态测量系统在测姿过程中测姿精度和稳定性不高的问题,提出了"北斗"卫星导航系统(BDS)/惯性导航系统(INS)紧耦合姿态测量算法。该算法首先利用BDS观测量设计了BDS系统测姿误差模型;然后以INS状态误差方程为滤波系统状态... 详细信息

针对"北斗"卫星姿态测量系统在测姿过程中测姿精度和稳定性不高的问题,提出了"北斗"卫星导航系统(BDS)/惯性导航系统(INS)紧耦合姿态测量算法。该算法首先利用BDS观测量设计了BDS系统测姿误差模型;然后以INS状态误差方程为滤波系统状态方程,以载波相位为主要观测量设计了扩展卡尔曼滤波器,利用滤波器的输出实现对惯性导航测姿系统的辅助校正;最后采用静态测试、动态测试和遮挡测试验证该算法。该系统可以有效提高BDS测姿精度与输出频率,并且在静态条件下航向角测量精度可以达到0.15°。

关键词： “北斗”导航系统惯性导航系统组合姿态测量载波相位扩展卡尔曼滤波

超亲水-水下超疏油ZnCo_(2)O_(4)-不锈钢的制备及油水分离性能研究

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表面技术 2024年第16期53卷 198-207页

作者：张跃忠沈静张少华武鹏鹏刘宝胜太原科技大学太原030024

目的通过简易的方法制备耐久性的油水分离材料。方法采用水热-退火方法在不锈钢网(SSM)基底上制备了ZnCo_(2)O_(4)纳米针状阵列(ZnCo_(2)O_(4)-SSM)。利用扫描电镜、X射线衍射仪、傅里叶变换红外光谱仪、X射线光电子能谱和接触角测量仪... 详细信息

目的通过简易的方法制备耐久性的油水分离材料。方法采用水热-退火方法在不锈钢网(SSM)基底上制备了ZnCo_(2)O_(4)纳米针状阵列(ZnCo_(2)O_(4)-SSM)。利用扫描电镜、X射线衍射仪、傅里叶变换红外光谱仪、X射线光电子能谱和接触角测量仪对油水分离材料的表面形貌、组分和表面润湿性进行了表征和研究。结果ZnCo_(2)O_(4)-SSM空气中水的接触角为0°,水下油的接触角≥155°,显示了超亲水-水下超疏油的特殊润湿性。ZnCo_(2)O_(4)-SSM呈现出优异的抗油污性能和重力驱动油水分离性能。对油-水混合物的分离效率大于99.8%,通量为3861~6114 L/(m^(2)·h),对水包油乳液的分离效率大于99.5%,通量为231~322 L/(m^(2)·h)。ZnCo_(2)O_(4)-SSM具有循环使用稳定性,在连续分离煤油-水混合物30次后,分离效率仍然能够达到99.8%以上。更重要的是,ZnCo_(2)O_(4)-SSM显示了优秀的长期稳定性、机械耐久性和强腐蚀环境耐久性(强酸,pH=1;强碱,pH=14;高盐,3.5%(质量分数)NaCl溶液)。结论ZnCo_(2)O_(4)-SSM以不锈钢网为载体,弥补了机械强度差的缺点。ZnCo_(2)O_(4)-SSM以高化学稳定的ZnCo_(2)O_(4)作为微纳米结构,提高了分离材料的耐久性。因此,ZnCo_(2)O_(4)-SSM制备方法简单,在工业含油污水的分离中具有很好的潜在应用前景。

关键词：油水分离不锈钢网 ZnCo_(2)O_(4) 耐久性润湿性

维普期刊数据库博看期刊

Mn添加对挤压态Mg-Zn-Y-Nd合金微观组织和腐蚀行为的影响

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稀有金属材料与工程 2021年第1期50卷 49-55页

作者：刘宝胜王亚宁张跃忠候利锋卫英慧太原科技大学材料科学与工程学院山西太原030024 太原理工大学材料科学与工程学院山西太原030024

通过光学显微镜,配备能量色散谱仪的扫描电子显微镜,X射线衍射仪,浸泡法和电化学测试的方法研究了Mn的添加对挤压Mg-Zn-Y-Nd合金在3.5%(质量分数)NaCl溶液中的微观组织和腐蚀行为的影响。结果表明,在研究的Mg-Zn-Y-Nd合金中添加Mn可以诱... 详细信息

通过光学显微镜,配备能量色散谱仪的扫描电子显微镜,X射线衍射仪,浸泡法和电化学测试的方法研究了Mn的添加对挤压Mg-Zn-Y-Nd合金在3.5%(质量分数)NaCl溶液中的微观组织和腐蚀行为的影响。结果表明,在研究的Mg-Zn-Y-Nd合金中添加Mn可以诱导Mg3Y2Zn3(I相)沉淀,可以抑制热挤压过程中动态再结晶(DRX)晶粒的粗化。同时,添加了Mn也可以提高合金的耐腐蚀性。不含Mn的Mg-5.6Zn-1Y-0.4Nd合金与含锰1.0%的Mg-5.6Zn-1Y-0.4Nd合金腐蚀速率分别为18.78和9.89 mm·a^(-1)。而耐腐蚀性的提高主要归因于腐蚀产物层保护性的增强。

关键词： Mg-Zn-Y-Nd合金 Mn含量微观组织动态再结晶耐腐蚀性

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论现代语境中的西方大学变迁

理工高教研究 2005年第2期24卷 30-31,42页

作者：张跃忠苏州大学

大学变迁存在着路径依赖,本文从现代性的特征出发,从教学内容的变革、学术自由的演进和竞争的理性化三个方面入手,理解教育的现代性和现代大学的特质,以此诠释大学变迁的动因和路径。

关键词：语境西方国家大学教学内容学术自由

改良Karlsson手术治疗陈旧性跟腓韧带损伤效果的回顾分析

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中华医学杂志 2019年第11期99卷 818-822页

作者：赵峰胡跃林江东焦晨张跃钟北京大学第三医院运动医学研究所北京100191 航天中心医院骨科北京100049

目的通过随访评价改良Karlsson手术(锚钉法)治疗陈旧性跟腓韧带断裂的治疗效果及其影响因素。方法对2010年8月至2014年5月北京大学第三医院运动医学研究所手术治疗的24例跟腓韧带断裂的患者资料进行回顾性分析,所有病例均使用改良Karls... 详细信息

目的通过随访评价改良Karlsson手术(锚钉法)治疗陈旧性跟腓韧带断裂的治疗效果及其影响因素。方法对2010年8月至2014年5月北京大学第三医院运动医学研究所手术治疗的24例跟腓韧带断裂的患者资料进行回顾性分析,所有病例均使用改良Karlsson手术(锚钉法)解剖修复跟腓韧带。其中男14例,女10例。平均年龄(30±9)岁。体质指数(BMI)平均(25±5)kg/m^2。随访并分析术前和术后疼痛视觉模拟评分(VAS评分)、美国足踝外科协会评分(AOFAS评分)、Tegner膝关节运动评分、踝关节稳定性及活动度等。手术前后正态分布数据比较应用配对设计的t检验。结果术后平均随访(41±13)个月。与术前相比,末次随访时VAS评分明显下降[0(0,7)比5(0,8),Z=4.13,P=0.000],AOFAS评分明显提高[(94±10)分比(70±14)分,t=8.94,P<0.05],Tegner评分明显提高[(4.7±1.5)分比(2.8±1.3)分,t=6.87,P<0.05],均明显改善。AOFAS评分优19例,良4例,中1例,优良率95.8%;其中20例(83.3%)患者对术后恢复效果满意。术后再次扭伤5例(20.8%),踝关节活动度受限3例(12.5%)。结论采用改良Karlsson手术(锚钉法)治疗陈旧性跟腓韧带断裂可恢复踝关节的稳定性,是慢性踝关节外侧不稳定的有效治疗方法。

关键词：跟腓韧带断裂改良Karlsson手术慢性踝关节不稳

高中语文学习任务群的出场语境、价值意蕴和实践策略

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江苏教育研究 2020年第10期 54-57页

作者：张跃忠太仓市教育局江苏苏州215400

学习任务群教学是高中语文课程教学的新样态,聚焦培育语文核心素养,发挥了育人的综合功能。学习任务群出场语境是对学习主体的自我唤醒和立德树人的时代回应,体现了整体化的教学思维和语用教学的评价导向,需要在核心知识与问题预设,情... 详细信息

学习任务群教学是高中语文课程教学的新样态,聚焦培育语文核心素养,发挥了育人的综合功能。学习任务群出场语境是对学习主体的自我唤醒和立德树人的时代回应,体现了整体化的教学思维和语用教学的评价导向,需要在核心知识与问题预设,情境创设和思维提升上实现路径突破。

关键词：高中语文学习任务群核心素养项目化学习