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China Foundry 2024年第5期21卷 577-587页

作者： Wei-li Peng jian-hua zhao Cheng Gu Ya-jun Wang College of Materials Science and Engineering Chongqing UniversityChongqing 400045China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

The properties of the magnetic mold in magnetic mold casting directly determine the quality of the final cast *** this study,the magnetic mold properties in magnetic mold casting,were studied utilizing a coupled electromagnetic-structural method through numerical *** study investigated key factors including equivalent stress,the distribution of tensile and compressive stresses,and the area ratio of tensile *** compared molds made entirely of magnetic materials with those made partially of magnetic *** results indicate that as current increases from 4 A to 8 A,both the initial magnetic mold and the material-replaced magnetic mold initially show an increasing trend in equivalent stress,tensile-compressive stress,and the area ratio of tensile stress,peaking at 6 A before *** material replacement,the area ratio of tensile stress at 6 A decreases to 19.84%,representing a reduction of 29.72%.Magnetic molds comprising a combination of magnetic and non-magnetic materials exhibit sufficient strength and a reduced area ratio of tensile stress compared to those made entirely from magnetic *** study provides valuable insights for optimizing magnetic mold casting processes and offers practical guidance for advancing the application of magnetic molds.

关键词： magnetic mold casting coupled electromagnetic-structural method numerical simulation stress analysis

The RNA-binding domain of DCL3 is required for long-distance RNAi signaling

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aBIOTECH 2024年第1期5卷 17-28页

作者： Jie Li Bo-Sen Zhang hua-Wei Wu Cheng-Lan Liu Hui-Shan Guo jian-hua zhao State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic Interactions University of the Chinese Academy of SciencesBeijing 100049China Qilu Zhongke Academy of Modern Microbiology Technology Jinan 250022China

Small RNA(sRNA)-mediated RNA silencing(also known as RNA interference,or RNAi)is a conserved mechanism in eukaryotes that includes RNA degradation,DNA methylation,heterochromatin formation and protein translation *** plants,sRNAs can move either cell-to-cell or systemically,thereby acting as mobile silencing signals to trigger noncell autonomous ***,whether and what proteins are also involved in noncell autonomous silencing have not been *** this study,we utilized a previously reported inducible RNAi plant,PDSi,which can induce systemic silencing of the endogenous PDS gene,and we demonstrated that DCL3 is involved in systemic PDS silencing through its RNA binding *** confirmed that the C-terminus of DCL3,including the predicted RNA-binding domain,is capable of binding short *** affecting RNA binding,but not processing activity,reduced systemic PDS silencing,indicating that DCL3 binding to RNAs is required for the induction of systemic *** mosaic virus infection assays showed that the RNA-binding activity of DCL3 is required for antiviral RNAi in systemically noninoculated *** findings demonstrate that DCL3 acts as a signaling agent involved in noncell autonomous silencing and an antiviral effect in addition to its previously known function in the generation of 24-nucleotide sRNAs.

关键词： RNAi signaling DCL3 RBD RNAs Cucumber mosaic virus

Current-Induced Magnetization Switching Behavior in Perpendicular Magnetized L1_(0)-MnAl/B2-CoGa Bilayer

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Chinese Physics Letters 2024年第5期41卷 138-143页

作者：孙宏利韩荣坤秦红蕊赵旭鹏谢志成魏大海赵建华 State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100190China International School of Microelectronics Dongguan University of TechnologyDongguan 523808China

Rare-earth-free Mn-based binary alloy L1_(0)-MnAl with bulk perpendicular magnetic anisotropy(PMA) holds promise for high-performance magnetic random access memory(MRAM) devices driven by spin-orbit torque(SOT). However, the lattice-mismatch issue makes it challenging to place conventional spin current sources, such as heavy metals, between L1_(0)-MnAl layers and substrates. In this work, we propose a solution by using the B2-CoGa alloy as the spin current source. The lattice-matching enables high-quality epitaxial growth of 2-nm-thick L1_(0)-MnAl on B2-CoGa, and the L1_(0)-MnAl exhibits a large PMA constant of 1.04 × 10^(6)J/m^(3). Subsequently, the considerable spin Hall effect in B2-CoGa enables the achievement of SOT-induced deterministic magnetization switching. Moreover, we quantitatively determine the SOT efficiency in the bilayer. Furthermore, we design an L1_(0)-MnAl/B2-CoGa/Co_(2)MnGa structure to achieve field-free magnetic switching. Our results provide valuable insights for achieving high-performance SOT-MRAM devices based on L1_(0)-MnAl alloy.

关键词： alloy enable holds

Publisher Correction: The RNA-binding domain of DCL3 is required for long-distance RNAi signaling

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aBIOTECH 2024年第1期5卷 114-114页

Correction to:aBIOTECH https://***/10.1007/s42994-023-00124-6 The copyright holder for this article was incorrectly given as‘Agricultural Information Institute,Chinese Academy of Agricultural Sciences’but should have been‘The Authors’This article was originally published with the incorrect licence;it should have been:Open Access This article is licensed under a Creative Commons Attribution 4.0 International License,which permits use,sharing,adaptation.

关键词： DCL Open Creative Access Publisher

增材制造钛基金字塔点阵结构对镁/钛双金属复合材料界面强化的优化

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Transactions of Nonferrous Metals Society of China 2024年第3期34卷 846-860页

作者：吴远兵赵建华彭韦力辜诚程进王亚军重庆大学材料科学与工程学院重庆400045 重庆大学国家镁合金工程研究中心重庆400044

采用超声辅助固-液复合铸造的方法,通过在界面处采用增材制造的钛基金字塔型点阵材料制备镁/钛异种双金属复合材料。采用正交法对点阵结构参数进行优化。结果表明,优化后的点阵结构参数为:杆直径(d)1 mm,杆长与杆直径比(l/d)3,上节点和... 详细信息

采用超声辅助固-液复合铸造的方法,通过在界面处采用增材制造的钛基金字塔型点阵材料制备镁/钛异种双金属复合材料。采用正交法对点阵结构参数进行优化。结果表明,优化后的点阵结构参数为:杆直径(d)1 mm,杆长与杆直径比(l/d)3,上节点和下节点直径与杆直径比(d_(1)/d,d_(2)/d)均为2.5,其中l/dd是影响接头失效强度的最显著因素,最优点阵结构参数下镁/钛双金属接头的失效强度为77.3 MPa。实验结果和有限元分析表明:随着点阵结构长径比的增加,镁/钛双金属接头的失效强度先增加后减小,当长径比为3时,失效强度达到最大。

关键词：镁/钛双金属复合材料金字塔点阵结构优化增材制造失效强度有限元分析

Finns-Kingdom RNA Silencing in Plant-Fungal Pathogen Interactions

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Molecular Plant 2018年第2期11卷 235-244页

作者： Chenlei hua jian-hua zhao Hui-Shan Guo State Key Laboratory of Plant Genomics Institute of Microbiology Chinese Academy of Sciences 100101 Beijing China College of Life Science University of the Chinese Academy of Sciences 100049 Beijing China

Fungal pathogens represent a major group of plant invaders that are the causative agents of many notorious plant diseases. Large quantities of RNAs, especially small RNAs involved in gene silencing, have been found to transmit bidirectionally between fungal pathogens and their hosts. Although host-induced gene silencing （HIGS） technology has been developed and applied to protect crops from fungal infections, the mechanisms of RNA transmission, especially small RNAs regulating trans- kingdom RNA silencing in plant immunity, are largely unknown. In this review, we summarize and discuss recent important findings regarding trans-kingdom sRNAs and RNA silencing in plant-fungal pathogen interactions compared with the well-known RNAi mechanisms in plants and fungi. We focus on the interactions between plant and fungal pathogens with broad hosts, represented by the vascular pathogen Verticillium dahliae and non-vascular pathogen Botrytis cinerea, and discuss the known instances of natural RNAi transmission between fungal pathogens and host plants. Given that HIGS has been developed and recently applied in controlling Verticillium wilt diseases, we propose an ideal research system exploiting plant vasculature-Verticillium interaction to further study trans-kingdom RNA silencing.

关键词： fungal pathogens HIGS microRNA trans-kingdom RNAi small RNA Verticillium dahliae

RNA silencing:From discovery and elucidation to application and perspectives

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Journal of Integrative Plant Biology 2022年第2期64卷 476-498页

作者： jian-hua zhao Hui-Shan Guo State Key Laboratory of Plant Genomics Institute of Microbiologythe Chinese Academy of SciencesBeijing100101 China CAS Center for Excellence in Biotic Interactions University of the Chinese Academy of SciencesBeijing100049 China

RNA silencing(or RNA interference,RNAi)is a conserved mechanism for regulating gene expression in *** discovery of natural trans-kingdom RNAi indicated that small RNAs act as signaling molecules and enable communication between organisms in different *** phenomenon and potential mechanisms of trans-kingdom RNAi are among the most exciting research *** better understand trans-kingdom RNAi,we review the history of the discovery and elucidation of RNAi *** on canonical RNAi mechanisms,we summarize the major points of divergence around RNAi pathways in the main eukaryotes’kingdoms,including plants,animals,and *** review the representative incidents associated with the mechanisms and applications of trans-kingdom RNAi in crop protection,and discuss the critical factors that should be considered to develop successful trans-kingdom RNAi-based crop protection strategies.

关键词： crop protection gene expression RNA silencing small RNAs trans-kingdom RNAi

Influence of Self-excited Vibrating Cavity Structure on Droplet Diameter Characteristics of Twin-fluid Nozzle

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 192-201页

作者： Bo Chen Dian-Rong Gao Shao-Feng Wu jian-hua zhao School of Mechanical Engineering Yanshan University School of Mechanical Engineering Hangzhou Dianzi University State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University

It is a great challenge to find effective atomizing technology for reducing industrial pollution; the twin-fluid atomizing nozzle has drawn great attention in this field recently. Current studies on twin-fluid nozzles mainly focus on droplet breakup and single droplet characteristics. Research relating to the influences of structural parameters on the droplet diameter characteristics in the flow field is scarcely available. In this paper, the influence of a self-excited vibrating cavity structure on droplet diameter characteristics was investigated. Twin-fluid atomizing tests were performed by a self-built open atomizing test bench, which was based on a phase Doppler particle analyzer(PDPA). The atomizing flow field of the twin-fluid nozzle with a self-excited vibrating cavity and its absence were tested and analyzed. Then the atomizing flow field of the twin-fluid nozzle with different self-excited vibrating cavity structures was *** experimental results show that the structural parameters of the self-excited vibrating cavity had a great effect on the breakup of large droplets. The Sauter mean diameter(SMD) increased with the increase of orifice diameter or orifice depth. Moreover, a smaller orifice diameter or orifice depth was beneficial to enhancing the turbulence around the outlet of nozzle and decreasing the SMD. The atomizing performance was better when the orifice diameter was2.0 mm or the orifice depth was 1.5 mm. Furthermore, the SMD increased first and then decreased with the increase of the distance between the nozzle outlet and self-excited vibrating cavity, and the SMD of more than half the atomizing flow field was under 35 μm when the distance was 5.0 mm. In addition, with the increase of axial and radial distance from the nozzle outlet, the SMD and arithmetic mean diameter(AMD) tend to increase. The research results provide some design parameters for the twin-fluid nozzle, and the experimental results could serve as a beneficial suppleme

关键词： Atomizing nozzle Twin-fluid Sauter mean diameter Arithmetic mean diameter Self-excited vibrating cavity Phase Doppler particle analyzer

Macro-and Microstructure Evolution of 5CrNiMo Steel Ingots during Electroslag Remelting Process

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Journal of Iron and Steel Research International 2014年第7期21卷 644-652页

作者： Lei RAO jian-hua zhao Zhan-xi zhao Gang DING Mao-peng GENG College of Mechanical and Electronic Engineering Hohai University Xinya Special Steel Forging Co. Ltd. College of Mechanical and Electronic Engineering Nanchang University

A comprehensive mathematical model was established and used to simulate the macro and microstructure evolution during the production process of 5CrNiMo steel ingot by electroslag remelting （ESR） method. Along the ingot height, the macrostructure distribution characteristics changed from vertical, fine columnar grains to tilted, coarse columnar grains, and this transformation process occurred at the very beginning of ESR. In the cross section of the ingot, there were three grain morphology regions and two grain type transition regions from the outside to the center of the ingot. These regions were the fine columnar grain region, columnar competitive growth transition re gion, coarse columnar grain region, columnar to equiaxed grain transition （CET） region, and coarse equiaxed grain region. The influence of the remelting rate on the macrostructure and mlcrostructure was investigated using a series of experiments and simulations. The results showed that a low remelting rate could produce a small grain growth angle （GGA） ; the average secondary dendrite arm spacing （SDAS） firstly decreased and then increased as the remelting rate increased. An excessively high or low remelting rate can increase the GGA and average SDAS in ingots. Thus, the remelting rate should be controlled within a suitable range to reduce composition microsegregation and microshrinkage in the ingot to produce an ESR ingot with satisfactory hot forging performance.

关键词： electroslag remelting macrostructure microstructure remelting rate secondary dendrite arm spacing

Effect of HEA/Al composite interlayer on microstructure and mechanical property of Ti/Mg bimetal composite by solid-liquid compound casting

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China Foundry 2023年第1期20卷 1-11页

作者： Jin Cheng jian-hua zhao Chun Wang Jing-jing Shangguan Cheng Gu Ya-jun Wang College of Materials Science and Engineering Chongqing UniversityChongqing 400045China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China Beijing Power Machinery Research Institute Beijing 100074China

In this study,HEA/AI composite interlayer was used to fabricate Ti/Mg bimetal composites by solidliquid compound casting *** Al layer was prepared on the surface of TC4 alloy by hot dipping,and the FeCoNiCr HEA layer was prepared by magnetron sputtering onto the Al *** influence of the HEA layer thickness and pouring temperature on interface evolution was investigated based on SEM observation and thermodynamic *** indicate that the sluggish diffusion effect of HEA can effectively inhibit the interfacial diffusion between Al and Mg,which is conducive to the formation of solid solution,especially when the thickness of HEA is 800 *** the increase of casting temperature from 720 ℃ to 730 ℃,740℃,and 750 ℃,α-Al(Mg),α-Al(Mg)+Al3Mg2,Al3Mg2+Al12Mg17,and Al12Mg17+δ-Mg are formed at the interface of Ti/Mg bimetal,*** the thickness of the HEA layer is 800 nm and the pouring temperature is 720 ℃,the bonding strength of the Ti/Mg bimetal can reach the maximum of 93.6 MPa.

关键词： Ti/Mg bimetal composite microstructure solid-liquid compound casting HEA/Al composite interlayer mechanical property