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Acta Metallurgica Sinica(English Letters) 2009年第1期22卷 13-21页

作者： Dashan SUI Zhenshan cui National Die ＆ Mould CAD Engineering Research Center Shanghai Jiaotong UniversityShanghai 200030 China

The inverse heat conduction method is one of methods to identify the casting simulation parameters. A new inverse method was presented according to the Tikhonov regularization theory. One appropriate regularized functional was established, and the functional was solved by the sensitivity coefficient and Newtonaphson iteration method. Moreover, the orthogonal experimental design was used to estimate the appropriate initial value and variation domain of each variable to decrease the number of iteration and improve the identification accuracy and efficiency. It illustrated a detailed case of AlSiTMg sand mold casting and the temperature measurement experiment was done. The physical properties of sand mold and the interracial heat transfer coefficient were identified at the meantime. The results indicated that the new regularization method was efficient in overcoming the ill-posedness of the inverse heat conduction problem and improving the stability and accuracy of the solutions.

关键词： Orthogonal experimental design Regularization method Parameters identification Numerical simulation

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声波式机械天线的谐振频率调控方法

国防科技大学学报 2024年第4期46卷 96-103页

作者：崔勇李良亚王琛黄玉平袁志鸿陶云飞北京航空航天大学自动化科学与电气工程学院北京100191 北京精密机电控制设备研究所北京100076

声波式机械天线作为机械天线的重要类型之一,其谐振频率与固有频率高度耦合,而目前声波式机械天线受到材料尺寸限制,谐振频率较高,无法满足甚低频或更低频段的需求。为调控声波式机械天线的谐振频率,对声波式机械天线进行了振动建模,提... 详细信息

声波式机械天线作为机械天线的重要类型之一,其谐振频率与固有频率高度耦合,而目前声波式机械天线受到材料尺寸限制,谐振频率较高,无法满足甚低频或更低频段的需求。为调控声波式机械天线的谐振频率,对声波式机械天线进行了振动建模,提出了增加单边固定约束、增加自由端质量和去除天线部分材料三种方法,并通过有限元仿真对所提方法进行了验证。结果表明,三种方法均能有效调控声波式机械天线的谐振频率,且与解析模型具有良好的一致性。通过应力分布研究了三种调控谐振频率方法对天线辐射的电场强度或磁场强度的影响,对声波式机械天线的设计具有重要参考意义。

关键词：声波式机械天线甚低频固有频率有限元磁电复合材料

17-4PH不锈钢激光气体渗氮层显微组织与摩擦学性能

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表面技术 2024年第7期53卷 57-63页

作者：刘礼邵磊孙岩茹崔梓烁李克伟李文生山东科技大学材料科学与工程学院山东青岛266590 西北师范大学物理与电子工程学院兰州730070

目的提高17-4PH马氏体沉淀硬化不锈钢的表面硬度及耐磨性。方法采用光纤激光器对17-4PH不锈钢进行激光气体氮化,采用不同激光功率在其表面制备渗氮层。利用光学显微镜(OM)、电子扫描显微镜(SEM)和X射线衍射仪(XRD)等设备分析渗氮层的显... 详细信息

目的提高17-4PH马氏体沉淀硬化不锈钢的表面硬度及耐磨性。方法采用光纤激光器对17-4PH不锈钢进行激光气体氮化,采用不同激光功率在其表面制备渗氮层。利用光学显微镜(OM)、电子扫描显微镜(SEM)和X射线衍射仪(XRD)等设备分析渗氮层的显微组织和相组成;借助显微硬度仪测试渗氮层截面深度方向的硬度;采用多功能摩擦磨损试验机测试基体、渗氮层的摩擦学性能,并通过SEM分析磨痕形貌,揭示基体与渗氮层的磨损机制。结果在渗氮前样品组织为回火马氏体,经激光渗氮后样品表面形成了由板条马氏体组成的熔化区和回火马氏体组成的热影响区构成的渗氮层。经渗氮后,样品的硬度均得到提高。在激光功率3000 W下,渗氮层的表面硬度最高,达到了415HV0.2,约是基体硬度的1.2倍,渗氮层的硬度随着深度的增加呈下降趋势,在深度为2.6mm处其硬度与基体一致。在回火马氏体向板条马氏体转变的相变强化,以及氮原子(以固溶方式进入基体)的固溶强化作用下,提高了渗氮层的硬度。经渗氮后,样品的摩擦因数均高于基体,但渗氮后其磨损量相较于基体有所减少,在激光功率3000W下,其磨损体积最小,相较于基体减少了62%。在激光功率2500W下马氏体转变不完全,在激光功率3500W下渗氮层出现了裂纹,都降低了渗氮层的硬度,其耐磨性也随之减小,且都略低于在3000W下。磨损机制由渗氮前的以黏着磨损为主,转变为渗氮后的以磨粒磨损为主。结论在17-4PH马氏体沉淀硬化不锈钢表面进行激光渗氮后,其表面硬度和耐磨性均得到提高,在激光功率3000W下制备的渗氮层具有较高的表面硬度和优异的耐磨性。

关键词：激光气体渗氮 17-4PH马氏体沉淀硬化不锈钢显微组织表面硬度摩擦学性能

飞灰含碳在线测量在660 MW机组锅炉燃烧中应用

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冶金能源 2024年第1期43卷 54-56页

作者：张超柳宁绳鹏鹏崔小军陕西德源府谷能源有限公司

针对失重法飞灰测碳装置在取样及测量方面的不足,利用防堵耐磨等技术提高飞灰测碳装置的测量精度和取样稳定性,并将装置应用于660 MW机组锅炉智慧燃烧系统中,通过精准飞灰含碳测量反映炉内燃烧状态,确保燃烧优化控制模型预测的正确性。... 详细信息

针对失重法飞灰测碳装置在取样及测量方面的不足,利用防堵耐磨等技术提高飞灰测碳装置的测量精度和取样稳定性,并将装置应用于660 MW机组锅炉智慧燃烧系统中,通过精准飞灰含碳测量反映炉内燃烧状态,确保燃烧优化控制模型预测的正确性。研究结果表明,飞灰含碳实际值与预测值误差保持在较小范围内,最大误差不超过0.015%。优化燃烧系统后的现场运行结果表明,飞灰含碳量均值由2.1%降到1.5%,锅炉效率平均提高0.21%。

关键词：飞灰含碳在线测量技术防堵耐磨智慧燃烧

Segregation in squeeze casting 6061 aluminum alloy wheel spokes and its formation mechanism

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China Foundry 2021年第1期18卷 45-51页

作者： Fan-bo Meng Hong-jun Huang Xiao-guang Yuan Xue-jian Lin Ze-wen cui Xian-lei Hu School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China School of Materials Science and Engineering Liaoning Technology UniversityFuxin123000China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110004China

Segregation can seriously damage the mechanical properties of the aluminum alloys.6061 aluminum alloy wheel spokes were prepared by squeeze *** investigate the formation mechanism of segregation,the microstructure of the alloy was observed using scanning electron microscopy,energy dispersive spectrometry,X-ray diffraction and electron microprobe analysis *** Gibbs energy of each phase during solidification was calculated by JMat *** show that the segregation phases in the R-joint of the wheel spokes are mainly composed of Mg_(2)Si,β-Al Fe Si and Al_(5)Cu_(2)Mg_(8)Si_(6)*** the solidification of the 6061 aluminum alloy wheels,Mg_(2)Si andα-Al Fe Si phases precipitate in the mushy zone at *** the decrease of temperature,α-Al Fe Si transforms intoβ-Al Fe Si,while Al_(5)Cu_(2)Mg_(8)Si_(6)precipitates from the solid-state aluminum alloy after *** at the R-joint of wheel spokes is mainly caused by insufficient cooling,so the cooling during alloy solidification should be enhanced to avoid segregation.

关键词： 6061 aluminum wheels segregation squeeze casting Mg_(2)Si Al FeSi Al_(5)Cu_(2)Mg_(8)Si_(6)

Effect of ultrasonic melt treatment on degassing of Mg-6Zn-1Ca alloy

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China Foundry 2015年第1期12卷 15-19页

作者： Zheng Jia wen-ming Zhang Fu Yang Zhi-qiang Zhang Qi-chi Le Jian-zhong cui College of Mechanical Engineering Shenyang University Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern University

The effect of ultrasonic power and treatment time on degassing of Mg-6Zn-1Ca alloy was studied in this paper. The degassing effect was characterized by measuring densities of ingots. The results show that proper ultrasonic treatment can remove hydrogen from the melt of the Mg-6Zn-1Ca alloy. The ultrasonic degassing effect is closely related to the ultrasonic power density and treatment time. The degassing efficiency increases with an increase in ultrasonic power density when the melt is treated at 690 °C for 120 s, reaching its highest value at 1.2 W·cm-3. When the power density is 1.2 W·cm-3, with an increase in ultrasonic treatment time, the degassing efficiency increases at first, reaches its peak value at 120 s, then decreases as the ultrasonic treatment is further prolonged. In this experiment, the optimum degassing effect with an efficiency of 67.5 % is obtained by ultrasonic treatment with the power density of 1.2 W·cm-3 for 120 s. The maximum density of ingot can be increased from 1.8069 g·cm-3 to 1.8146 g·cm-3(increased by 0.43%).

关键词： ultrasonic treatment degassing efficiency Mg-6Zn-1Ca alloy cavitation

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Chinese Medical Journal 2021年第2期134卷 178-184页

作者： Jing-Yi Liu Yi-Cheng Zhu Li-Xin Zhou Yan-Ping Wei Chen-Hui Mao Li-Ying cui Bin peng Ming Yao Department of Neurology Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China

Background:Homozygous or compound heterozygous mutations in high temperature requirement serine peptidase A1(HTRA1)gene are responsible for cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy(CARASIL).Recently,increasing evidence has shown that heterozygous HTRA1 mutations are also associated with cerebral small vessel disease(CSVD)with an autosomal dominant pattern of *** study was aimed to analyze the genetic and clinical characteristics of HTRA1-related autosomal dominant ***:We presented three new Chinese cases of familial CSVD with heterozygous HTRA1 mutations and reviewed all clinical case reports and articles on HTRA1-related autosomal dominant CSVD included in PUBMED by the end of March 1,*** probands with genetic diagnosis reported to date were also *** genetic and clinical characteristics of HTRA1-related autosomal dominant CSVD were summarized and analyzed by comparing with ***:Forty-four HTRA1-related autosomal dominant CSVD probands and 22 CARASIL probands were *** with typical CARASIL,HTRA1-related autosomal dominant probands has a higher proportion of vascular risk factors(P<0.001),a later onset age(P<0.001),and a relatively slower clinical *** and spondylosis can be observed,but less than those in the typical ***-five heterozygous mutations in HTRA1 were reported,most of which were missense *** acids located close to amino acids 250-300 were most frequently affected,followed by these located near 150∼*** amino acids 250∼300 were also the most frequently affected region in CARASIL patients,fewer mutations precede the 200th amino acids were detected,especially in the Kazal-type serine protease ***:HTRA1-related autosomal dominant CSVD is present as a mild phenotype of *** trend of regional concentration of mutation sites may be related to the concentration of key sites in these re

关键词： CARASIL Cerebral small vessel disease Heterozygous mutation HTRA1

Application of headed studs in steel fiber reinforced cementitious composite slab of steel beam-column connection

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Earthquake Engineering and Engineering Vibration 2012年第1期11卷 11-21页

作者： Yao cui Masayoshi Nakashima Center for Urban Earthquake Engineering Tokyo Institute of Technology Japan Disaster Prevention Research Institute Kyoto University Gokashyo Uji Kyoto Japan

Steel fiber reinforced cementitous composites （SFRCC） is a promising material with high strength in both compression and tension compared with normal concrete. The ductility is also greatly improved because of 6% volume portion of straight steel fibers. A steel beam-column connection with Steel fiber reinforced cementitous composites （SFRCC） slab diaphragms is proposed to overcome the damage caused by the weld. The push-out test results suggested that the application of SFRCC promises larger shear forces transferred through headed studs allocated in a small area in the slab. Finite element models were developed to simulate the behavior of headed studs. The failure mechanism of the grouped arrangement is fiarther discussed based on a series of parametric analysis. In the proposed connection, the SFRCC slab is designed as an exterior diaphragm to transfer the beam flange load to the column face. The headed studs are densely arranged on the beam flange to connect the SFRCC slab diaphragms and steel beams. The seismic performance and failure mechanism of the SFRCC slab diaphragm beam-column connection were investigated based on the cyclic loading test. Beam hinge mechanism was achieved at the end of the SFRCC slab diaphragm by using sufficient studs and appropriate rebars in the SFRCC slab.

关键词： multi-directional transmitting artificial boundary viscous-spring artificial boundary saturated soilfoundation Biot's equations

Multi-objective optimization in quantum parameter estimation

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Science China(Physics,Mechanics & Astronomy) 2018年第4期61卷 30-35页

作者： BeiLi Gong Wei cui School of Automation Science and Engineering South China University of Technology

We investigate quantum parameter estimation based on linear and Kerr-type nonlinear controls in an open quantum system, and consider the dissipation rate as an unknown parameter. We show that while the precision of parameter estimation is improved,it usually introduces a significant deformation to the system state. Moreover, we propose a multi-objective model to optimize the two conflicting objectives:(1) maximizing the Fisher information, improving the parameter estimation precision, and(2)minimizing the deformation of the system state, which maintains its fidelity. Finally, simulations of a simplified ε-constrained model demonstrate the feasibility of the Hamiltonian control in improving the precision of the quantum parameter estimation.

关键词： quantum parameter estimation Fisher information multi-objective optimization

铜换热表面MgO颗粒与碳酸钙混合污垢沉积特性的分子动力学模拟

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中国电机工程学报 2024年第6期44卷 2310-2318,I0019页

作者：孙金泽崔晓松徐志明贾玉婷王景涛东北电力大学能源与动力工程学院吉林省吉林市132012

为探究MgO颗粒与碳酸钙混合污垢在换热表面沉积特性与机理,该文采用分子动力学模拟方法分析MgO颗粒和碳酸钙混合体系在铜换热表面的沉积过程,并通过改变碳酸钙浓度讨论浓度对混合污垢沉积特性的影响规律。结果表明,在混合污垢沉积过程中... 详细信息

为探究MgO颗粒与碳酸钙混合污垢在换热表面沉积特性与机理,该文采用分子动力学模拟方法分析MgO颗粒和碳酸钙混合体系在铜换热表面的沉积过程,并通过改变碳酸钙浓度讨论浓度对混合污垢沉积特性的影响规律。结果表明,在混合污垢沉积过程中,碳酸钙团簇在颗粒与换热表面间起到连接作用,形成稳固的沉积状态。此外,MgO颗粒对离子缔合形成团簇过程中的动力学特性和结构特性有所影响。随着碳酸钙浓度由0.26 mol/L升至1.1 mol/L,换热表面直接吸附的碳酸钙团簇数量变多,MgO颗粒更容易通过碳酸钙团簇的相互作用沉积在换热表面。MgO颗粒促进了碳酸钙的缔合过程,碳酸钙促进了混合团簇的沉积,进而形成初始沉积阶段的混合污垢。

关键词：碳酸钙 MgO颗粒铜换热表面混合污垢沉积特性分子动力学模拟