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Structural reliability analysis and reliability-based design optimization: Recent advances

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Science China(Physics,Mechanics & Astronomy) 2013年第9期56卷 1611-1618页

作者： QIU ZhiPing HUANG Ren wang xiaojun QI WuChao Institute of Solid Mechanics Beihang University College of Aerospace Engineering Shenyang Aerospace University

We review recent research activities on structural reliability analysis,reliability-based design optimization(RBDO) and applications in complex engineering structural *** novel uncertainty propagation methods and reliability models,which are the basis of the reliability assessment,are *** addition,recent developments on reliability evaluation and sensitivity analysis are highlighted as well as implementation strategies for RBDO.

关键词： uncertainty propagation reliability assessment reliability-based design optimization hybrid reliability

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自适应调零天线动态性能影响因素研究

信息化研究 2024年第3期50卷 8-15页

作者：安国臣刘若凡王晓君河北科技大学信息科学与工程学院石家庄050018

本文针对卫星导航接收机的功率倒置(PI)算法在动态环境下受到最优权值处理速度的制约,导致动态抗干扰性能下降这一个问题,通过建立动态仿真环境,以七阵元均匀圆阵作为天线布阵的仿真模型,研究了不同权值更新速率对动态抗干扰性能的影响... 详细信息

本文针对卫星导航接收机的功率倒置(PI)算法在动态环境下受到最优权值处理速度的制约,导致动态抗干扰性能下降这一个问题,通过建立动态仿真环境,以七阵元均匀圆阵作为天线布阵的仿真模型,研究了不同权值更新速率对动态抗干扰性能的影响,证明了权值更新速率的提升对动态抗干扰性能也有相应的提高。并且分析了在不同快拍数以及不同时域抽头数对动态抗干扰性能的影响,证明了可以通过适当选择快拍数和时域抽头数来提高权值更新速率。本研究为建立更加完善的工程实现方案提供了理论依据,对存在类似需求的空时自适应调零天线抗干扰系统具有一定的参考价值。

关键词：功率倒置算法最优权值权值更新速率快拍数时域抽头数动态抗干扰性能

Host cell restriction factors of equine infectious anemia virus

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Virologica Sinica 2023年第4期38卷 485-496页

作者： Xue-Feng wang Xiangmin Zhang Weiwei Ma Jiwei Li xiaojun wang State Key Laboratory for Animal Disease Control and Prevention Harbin Veterinary Research Institute of Chinese Academy of Agricultural SciencesHarbin 150069China

Equine infectious anemia virus(EIAV)is a member of the lentivirus genus in the Retroviridae family and is considered an animal model for HIV/AIDS *** attenuated EIAV vaccine,which was successfully developed in the 1970s by classical serial passage techniques,is the first and only lentivirus vaccine that has been widely used to *** factors are cellular proteins that provide an early line of defense against viral replication and spread by interfering with various critical steps in the viral replication ***,viruses have evolved specific mechanisms to overcome these host barriers through *** battle between the viruses and restriction factors is actually a natural part of the viral replication process,which has been well studied in human immunodeficiency virus type 1(HIV-1).EIAV has the simplest genome composition of all lentiviruses,making it an intriguing subject for understanding how the virus employs its limited viral proteins to overcome restriction *** this review,we summarize the current literature on the interactions between equine restriction factors and *** features of equine restriction factors and the mechanisms by which the EIAV counteract the restriction suggest that lentiviruses employ diverse strategies to counteract innate immune *** addition,we present our insights on whether restriction factors induce alterations in the phenotype of the attenuated EIAV vaccine.

关键词： Equine infectious anemia virus(EIAV) Restriction factor Lentivirus

Self-lubricate and anisotropic wear behavior of AZ91D magnesium alloy reinforced with ternary Ti_2AlC MAX phases

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Journal of Materials Science & Technology 2019年第3期35卷 275-284页

作者： Wenbo Yu Deqiang Chen Liang Tian Hongbin Zhao xiaojun wang Center of Materials Science and Engineering School of Mechanical and Electronic Control Engineering Beijing Jiaotong University National United Engineering Laboratory for Advanced Bearing Tribology Henan University of Science and Technology Department of Materials Science and Engineering University of Michigan State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous Metals School of Materials Science and Engineering Harbin Institute of Technology

The dry sliding wear behavior of Ti_2AlC reinforced AZ91 magnesium composites was investigated at sliding velocity of 0.5 m/s under loads of 10, 20, 40 and 80 N using pin-on-disk configuration against a Cr15 steel disc. Wear rates and friction coefficients were registered during wear tests. Worn tracks and wear debris were examined by scanning electron microscopy, energy dispersive X-ray spectrometry and transmission electron microscopy in order to obtain the wear mechanisms of the studied materials. The main mechanisms were characterized as the magnesium matrix oxidation and self-lubrication of Ti_2AlC MAX phase. In all conditions, the composites exhibit superior wear resistance and self-lubricated ability than the AZ91 Mg alloy. In addition, the anisotropic mechanisms in tribological properties of textured Ti_2AlC-Mg composites were confirmed and discussed.

关键词： Ti2AlC Dry sliding wear Magnesium alloy Self-lubricate ability

基于改进TD3算法的智能通信干扰决策方法研究

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信息化研究 2024年第1期50卷 13-17,23页

作者：安国臣毕胜王晓君河北科技大学信息科学与工程学院石家庄050091

本文对通信对抗中干扰决策方法展开研究,旨在解决人为手动干扰决策带来的对抗方式单一、极易被敌军发现、干扰效率不佳等问题。随着科技的发展,各种电子技术层出不穷,这就导致电子战争中的环境变得越来越复杂,为了应对这种复杂的环境,... 详细信息

本文对通信对抗中干扰决策方法展开研究,旨在解决人为手动干扰决策带来的对抗方式单一、极易被敌军发现、干扰效率不佳等问题。随着科技的发展,各种电子技术层出不穷,这就导致电子战争中的环境变得越来越复杂,为了应对这种复杂的环境,并达到预期的干扰效果,本文提出一种基于改进双延迟深度确定性策略梯度算法(TD3)的智能通信干扰决策方法,以解决通信干扰过程中的干扰决策问题。TD3算法不仅能够应对连续动作空间而且具有高稳定性的特点。另外,改进的TD3算法使学习的过程更加迅速,算法的结果也更加收敛。仿真结果表明,基于该算法的改进,通信干扰成功率比原算法提升了28%。

关键词：通信干扰深度强化学习 TD3 干扰决策

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中试沸石曝气生物滤池用于低氨氮废水亚硝化

环境科学学报 2024年第1期44卷 175-183页

作者：章裕黄林祥汪晓军李嘉懿周松伟陈振国华南理工大学环境与能源学院广州510006 佛山市化尔铵生物科技有限公司佛山528300

为了避免稀土矿开采山体残留的氨氮形成持续的氮污染,亟需低碳节能地处理此类低浓度氨氮废水.本研究构建了以沸石为基质的30 m^(3)沸石曝气生物滤池(ZB AF)反应器,探究ZBAF实现低浓度氨氮稀土矿山尾水稳定亚硝化的可能性.从氮转化性能... 详细信息

为了避免稀土矿开采山体残留的氨氮形成持续的氮污染,亟需低碳节能地处理此类低浓度氨氮废水.本研究构建了以沸石为基质的30 m^(3)沸石曝气生物滤池(ZB AF)反应器,探究ZBAF实现低浓度氨氮稀土矿山尾水稳定亚硝化的可能性.从氮转化性能、抗冲击能力和微生物群落变化等角度,解析了ZBAF的亚硝化性能.结果表明:ZBAF经历5个周期快速启动,利用沸石对氨氮的吸附解吸特性及pH调控方法,提高了游离氨(FA)浓度,在维持氨氧化菌(AOB)活性的同时持续抑制亚硝酸盐氧化菌(NOB),反应器出水亚硝酸氮积累率可维持在90%以上,实现了长期稳定亚硝化.反应器最大亚硝氮产率(NPR_(max))可达0.33 kg·m^(-3)·d^(-1),得益于沸石吸附足量氨氮,曝气解吸的最大亚硝氮转换浓度ρ(NO_(2)^(-)-N)为330.41 mg·L^(-1).此外,破坏性实验表明,系统能在崩溃后快速恢复.高通量测序结果显示,反应器启动后,NOB被逐步淘汰,AOB的功能微生物亚硝基单胞菌(Nitrosomonas)相对丰度达到16.6%,分子生态网络分析显示Nitrosomonas是网络中的关键物种.本研究可为低浓度氨氮废水稳定亚硝化的工程化应用推广提供借鉴.

关键词：沸石曝气生物滤池(ZBAF) 低浓度氨氮亚硝化游离氨(FA) 高通量测序

Decoratable hybrid-film-patch stabilized Pickering emulsions and their catalytic applications

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Nano Research 2015年第8期8卷 2603-2610页

作者： Shenghua Ma Yinan wang Kunpeng Jiang xiaojun Han State Key Laboratory of Urban Water Resource and Environment School of Chemical Engineering and Technology Harbin Institute ofTechnology Harbin 150001 China

We demonstrated a method to fabricate functional hybrid film patches that were used to form Pickering emulsions （PEs）. The hybrid patches were made of carbon nanotubes, Fe3O4 nanoparticles, octadecyltrimethoxysilane, and poly（diallyldimethylammonium chloride）. The aqueous phase of the hybridpatch stabilized PEs can be easily separated by applying a magnetic field. The hybrid-film-patch stabilized PEs are extremely stable and lasted for eight months at room temperature. Furthermore, they are easily ruptured by adding ethanol, and regenerated by vortexing the patches in aqueous/oil mixtures, enabling the inner hydrophilic side of the patches to be easily modified with metal nanoparticles. As an example, palladium nanoparticles were embedded into the surface of the hybrid patches using an in situ reduction method. The Pd functionalized patch formed PEs showed an excellent catalytic performance for the hydrogenation of acetone with a yield of 99.5%. The same batch of Pd functionalized patches was recycled 13 times without loss of the catalytic activity. The hybrid-patch formed PEs have a great potential in the catalytic field.

关键词： Pickering emulsion hybrid film patches catalysis carbon nanotubes Fe3O4 nanoparticles

Crystallization kinetics of (Ni_(0.75)Fe_(0.25)_(78-x)Nb_xSi_(10)B_(12)(x=0,5)amorphous alloys

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Rare Metals 2006年第4期25卷 342-348页

作者： CHEN Xueding WEI Hengdou wang xiaojun State Key Laboratory of Advanced New Non-ferrous Materials l.anzhou University of Technology l.anzhou 730050 China

Amorphous ribbons of （Ni0.75Fe0.25）78-xNbxSi10B12 （x = 0, 5） were prepared by a single roller melt-spinning technique in air atmosphere. The crystallization kinetics of the alloys were investigated by means of continuous heating, and the activation energies of the alloys were calculated using Kissinger plot method and Ozawa plot method on the basis of differential thermal analysis data. The crystallization products were analyzed by X-ray diffraction. After the （Ni0.75Fe0.25）78Si10B12 amorphous alloy was annealed at the temperatures 715 and 745 K, a single phase of γ-（Fe, Ni） solid solution with grain sizes of about 10.3 and 18.5 nm, respectively, precipitates in the amorphous matrix. The crystallized phases are γ-（Fe, Ni） solid solution, Fe2Si, Ni2Si, and Fe3B after annealing at 765 K. The （Ni0.75Fe0.25）73NbsSi10 B12 amorphous alloy was annealed at 720, 750, and 800 K; and the crystallization phases, γ（Fe, Ni） solid solution, （Fe, Ni）23B6. Ni31Si12 and Nb2NiB0.16 form simultaneously.

关键词： amorphous materials thermal analysis crystallization kinetics activation energy

CPE增容TPU/PVC共混弹性体及相形态

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工程塑料应用 2024年第6期52卷 170-175页

作者：张青海陈汝盼欧阳娜王小君林松柏黎明职业大学新材料与鞋服工程学院福建泉州362000

为提高热塑性聚氨酯弹性体(TPU)与聚氯乙烯(PVC)的相容性,以氯化聚乙烯(CPE)为增容剂,经双螺杆挤出机熔融共混制备TPU/PVC共混型热塑性弹性体,测试了不同CPE用量的共混弹性体的拉伸强度、断裂伸长率和硬度等力学性能,以及动态流变性能... 详细信息

为提高热塑性聚氨酯弹性体(TPU)与聚氯乙烯(PVC)的相容性,以氯化聚乙烯(CPE)为增容剂,经双螺杆挤出机熔融共混制备TPU/PVC共混型热塑性弹性体,测试了不同CPE用量的共混弹性体的拉伸强度、断裂伸长率和硬度等力学性能,以及动态流变性能、动态力学性能和热稳定性。通过扫描电子显微镜(SEM)对共混弹性体的相态结构进行研究。结果表明,当TPU/PVC质量比为70/30时,共混弹性体综合力学性能最佳,拉伸强度为19.92 MPa,断裂伸长率为972%。随着CPE用量的增加,TPU/PVC共混弹性体的拉伸强度、断裂伸长率、硬度等均先增大后减小;CPE用量为6份时,TPU/PVC共混弹性体拉伸强度达到最大,为23.73 MPa,相较未加CPE时提高19.1%。加入CPE的共混弹性体复数黏度和储能模量均呈下降趋势。此外,CPE的加入还能有效提升弹性体高温热稳定性,TPU和PVC两种组分的损耗因子峰内移靠近,共混弹性体液氮脆断面的SEM照片显示PVC相筹明显变小且更为均匀,以上说明CPE对共混弹性体的增塑、增容作用明显,且CPE用量为6份时增容效果最佳。

关键词：塑性聚氨酯弹性体聚氯乙烯增容剂相态结构力学性能