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| 1 | Convex shaping process simulation during counter-rotating electrochemical machining by using the finite element method显示文摘In counter-rotating electrochemical machining(CRECM), a revolving cathode tool with hollow windows of various shapes is used to fabricate convex structures on a revolving part. During this process, the anode workpiece and the cathode tool rotate relative to each other at the same rotation speed. In contrast to the conventional schemes of ECM machining with linear motion of a block tool electrode, this scheme of ECM is unique, and has not been adequately studied yet. In this paper, the finite element method(FEM) is used to simulate the anode shaping process during CRECM, and the simulation process which involves a meshing model, a moving boundary,and a simulation algorithm is described. The simulated anode profiles of the convex structure at different processing times show that the CRECM process can be used to fabricate convex structures of various shapes with different heights. Besides, the variation of the inter-electrode gap indicates that this process can also reach a relative equilibrium state like that in conventional ECM. A rectangular convex and a circular convex are successfully fabricated on revolving parts. The experimental results indicate relatively good agreement with the simulation results. The proposed simulation process is valid for convex shaping prediction and feasibility studies as well. | Wang Dengyong Zhu Zengwei Wang Hongrui Zhu Di | 2016 | Chinese Journal of Aeronautics2016，29，2： | 8 |
| 2 | Effects of Shielding Coatings on the Anode Shaping Process during Counter-rotating Electrochemical Machining显示文摘Electrochemical machining(ECM) has been widely used in the aerospace, automotive, defense and medical industries for its many advantages over traditional machining methods. However, the machining accuracy in ECM is to a great extent limited by the stray corrosion of the unwanted material removal. Many attempts have been made to improve the ECM accuracy, such as the use of a pulse power, passivating electrolytes and auxiliary electrodes. However, they are sometimes insufficient for the reduction of the stray removal and have their limitations in many cases. To solve the stray corrosion problem in CRECM, insulating and conductive coatings are respectively used. The different implement processes of the two kinds of coatings are introduced. The effects of the two kinds of shielding coatings on the anode shaping process are investigated. Numerical simulations and experiments are conducted for the comparison of the two coatings. The simulation and experimental results show that both the two kinds of coatings are valid for the reduction of stray corrosion on the top surface of the convex structure. However, for insulating coating, the convex sidewall becomes concave when the height of the convex structure is over 1.26 mm. In addition, it is easy to peel off by the high-speed electrolyte. In contrast, the conductive coating has a strong adhesion, and can be well reserved during the whole machining process. The convex structure fabricated by using a conductive iron coating layer presents a favorable sidewall profile. It is concluded that the conductive coating is more effective for the improvement of the machining quality in CRECM. The proposed shielding coatings can also be employed to reduce the stray corrosion in other schemes of ECM. | WANG Dengyong ZHU Zengwei WANG Ningfeng ZHU Di | 2016 | Chinese Journal of Mechanical Engineering2016，29，5： | 6 |
| 3 | The pulsed high magnetic field facility and scientific research at Wuhan National High Magnetic Field Center显示文摘Wuhan National High Magnetic Field Center(WHMFC)at Huazhong University of Science and Technology is one of the top-class research centers in the world,which can offer pulsed fields up to 90.6 T with different field waveforms for scientific research and has passed the final evaluation of the Chinese government in 2014.This paper will give a brief introduction of the facility and the development status of pulsed magnetic fields research at WHMFC.In addition,it will describe the application development of pulsed magnetic fields in both scientific and industrial research. | Xiaotao Han Tao Peng Hongfa Ding Tonghai Ding Zengwei Zhu Zhengcai Xia Junfeng Wang Junbo Han Zhongwen Ouyang Zhenxing Wang Yibo Han Houxiu Xiao Quanliang Cao Yiliang Lv Yuan Pan Liang Li | 2017 | Matter and Radiation at Extremes2017，2，6： | 5 |
| 4 | Abrasive-assisted Nickel Electroforming Process with Moving Cathode显示文摘In traditional electroforming process for revolving parts with complex profiles, the drawbacks on surface of deposits, such as pinholes and nodules, will lead to varying physical and mechanical properties on different parts of electroformed components. To solve the problem,compositely moving cathode is employed in abrasive-assisted electroforming of revolving parts with complicated profiles. The cathode translates and rotates simultaneously to achieve uniform friction effect on deposits without drawbacks. The influences of current density and translation speed on the microstructure and properties of the electroformed nickel layers are investigated. It is found that abrasive-assisted electroforming with compound cathode motion can effectively remove the pinholes and nodules,positively affect the crystal nucleation, and refine the grains of layer. The increase of current density will lead to coarse microstructure and lower micro hardness, from 325 HV down to 189 HV. While, faster translational linear speed produces better surface quality and higher micro hardness, from 236 HV up to 283 HV. The weld-ability of the electroformed layers are also studied through the metallurgical analysis of welded joints between nickel layer and 304 stainless steel. The electrodeposited nickel layer shows fine performance in welding. The novel compound motion of cathode promotes the mechanical properties and refines the microstructure of deposited layer. | Jianhua REN Zengwei ZHU Chunqiu XIA Ningsong QU Di ZHU | 2017 | Chinese Journal of Mechanical Engineering2017，30，2： | 4 |
| 5 | Mechanical electrodeposition of bright nanocrystalline nickel显示文摘A new mechanical electrodeposition technology was proposed, and nanocrystalline nickel deposit with bright and smooth surface was prepared in the bath without any additive agents. Unlike traditional methods, the novel technology employed dynamical hard particles to continuously polish the cathode surface and disturb the nearby solution during electrodepositing. Experimental results showed that the polishing effect of hard particles can effectively prevent the hydrogen bubbles and impurities from adhering on the deposit surface and avoid the production of pits, pinholes and nodules. Furthermore, comparing with the deposit prepared by traditional methods, the one prepared by the novel technology was substantially refined with grain size ranging from 30 to 80 nm. Every diffraction peak's intensity of the deposit was reduced, the preferential orientation degree of (200) decreased and those of (111) and (220) increased. The microhardness notably increased. The magnetic properties were also changed with decreased saturation magnetization and increased coercive force. It was also found that variation of current density and cathode rotational speed could affect the structure and properties of the nickel deposits prepared by this technology. | ZHU ZengWei ZHU Di QU NingSong | 2008 | Science China(Technological Sciences)2008，51，7： | 3 |
| 6 | Effects of process parameters on mechanical properties of abrasive-assisted electroformed nickel显示文摘A cathode mandrel with translational and rotational motion, which was supposed to obtain uniform friction effect on surface, was employed in abrasive-assisted electroforming for revolving parts with complex profile. The effects of current density, translational speed and rotational speed on the deposit properties were studied by orthogonal test. The tensile strength,elongation and micro hardness value were measured to find out how the factors affected the properties. The optimized results show that changes of current density affect the tensile strength of nickel layer most, while translational speed has the most remarkable influences on both elongation and micro hardness. The low rotational speed affects the properties least. In this experiment, a smooth nickel layer with tensile strength 581 MPa, elongation 17% and micro hardness 248 HV is obtained by the orthogonal test. | Ren Jianhua Zhu Zengwei Zhu Di | 2016 | Chinese Journal of Aeronautics2016，29，4： | 2 |
| 7 | 血停跳液对复杂型先天性心脏病心肌保护作用的研究显示文摘在52例复杂先天性心脏病心内矫正术中,应用血停跳液(BCP)加强心肌保护,与晶体停跳液(CCP)比较。记录转流前和再灌注10min时心肌ATP、环磷酰胺(CP)含量及术前,术后6、12、24、48、72h内肌酸磷酸激酶(CPK)、肌-脑混合肌酸磷酸激酶同工酶(CK-MB)、天门冬氨酸氨基转移酶(AST)、乳酸脱氢酶(LDH)变化。结果显示:BCP组心肌ATP、CP贮备较CCP组增加;术后72h内,BCP组CK-MB值低于CCP组。其峰值只是CCP组的55.2%(P<0.05)。血停跳液能增加心肌能量储备,提高心肌抗缺血的能力,减轻心肌损伤的程度。BCP心肌保护的效果优于CCP. | zhu Ping Wang Zengwei (Zhujiang Hospita1 , First Military Medical University, Guangzhou 5l0282) | 1995 | 解放军医学杂志1995，20，6： | 1 |
| 8 | Abrasive polishing assisted nickel electroforming process显示文摘 | Zhu Di Zhu Zengwei Qu Ningsong | 2006 | CIRP Annals-Manufacturing Technology2006，55，1： | 1 |
| 9 | Abrasive Polishing assisted nickel electroforming process 显示文摘 | Zhu Di Zhu Zengwei | 2006 | CIRP Annals-Manufacturing Technology2006，55，1： | 1 |
| 10 | Electrodeposition of bright nickel coating under perturbation of hard particles显示文摘 | Zengwei Zhu Di Zhu Ningsong Qu Weining Lei | 2006 | Materials and Design2006，，6： | 1 |
| 11 | Improved observation of colonized roots reveals the regulation of arbuscule development and senescence by drought stress in the arbuscular mycorrhizae of citrus显示文摘Citrus is the typical mycorrhizal fruit tree species establishing symbiosis with arbuscular mycorrhizal (AM) fungi. However, arbuscule development and senescence in colonized citrus roots, especially in response to drought stress, remain unclear, which is mainly due to the difficulty in clearing and staining lignified roots with the conventional method. Here, we improved the observation of colonized roots of citrus plants with the sectioning method, which enabled the clear observation of AM fungal structures. Furthermore, we investigated the effects of one week of drought stress on arbuscule development and senescence with the sectioning method. Microscopy observations indicated that drought stress significantly decreased mycorrhizal colonization (F%and M%) although it did not affect plant growth performance. Fluorescence probes (WGA 488 and/or Nile red) revealed that drought stress inhibited arbuscule development by increasing the percentage of arbuscules at the early stage and decreasing the percentages of arbuscules at the midterm and mature stages. Meanwhile, drought stress accelerated arbuscule senescence, which was characterized by the increased accumulation of neutral lipids. Overall, the sectioning method developed in this study enables the in-depth investigation of arbuscule status, and drought stress can inhibit arbuscule development but accelerate arbuscule senescence in the colonized roots of citrus plants. This study paves the way to elaborately dissecting the arbuscule dynamics in the roots of fruit tree species in response to diverse abiotic stresses. | Xilong Yin Wei Zhang Zengwei Feng Guangda Feng Honghui Zhu Qing Yao | 2024 | Horticultural Plant Journal2024，10，2： | 0 |
| 12 | Electrochemical machining of a convex strips structure on a revolving part by using site directed power interruption显示文摘Revolving parts with complex surface structures are widely used in machinery and mechanical equipment. The ECM process provides its adequacy to cut hard materials with different shapes, and its applications are widely increased, due to its outstanding advantages. In this paper, a new method for machining a convex strips structure on a cylinder by using site directed power interruption(SDPI) in the ECM process is presented. A variable correction value of the power-off time was defined and optimized to obtain the ideal interval for better machining accuracy and stability.The electric field distribution and the simulated convex profiles show that the stray current density can be reduced effectively by using the proposed method. The correction value has an important influence on the machining accuracy. A suitable correction value in the range of 0.6–1.2 s can effectively improve the machining accuracy of the convex strips structure. Experiments were also conducted to verify the proposed method. Results have confirmed that the stray corrosion on the convex strips surface is significantly reduced and the machining accuracy of convex strips structure is remarkably improved by using the proposed method with a suitable correction value in the ECM process. Finally, a convex strip with a height of 2 mm on a thin-wall revolving part was also produced successfully using a correction value of 0.9. | Yongcheng GE Zengwei ZHU Di ZHU Dengyong WANG | 2018 | Chinese Journal of Aeronautics2018，31，10： | 0 |
| 13 | Experimental observation of multiple topological nodal structure in LaSb_(2)显示文摘Unconventional fermions in the immensely studied topological semimetals are the source for rich exotic topological properties.Here,using symmetry analysis and first-principles calculations,we propose the coexistence of multiple topological nodal structure in LaSb_(2),including topological nodal surfaces,nodal lines and in particular eightfold degenerate nodal points,which have been scarcely observed in a single material.Further,utilizing angle-resolved photoemission spectroscopy,we confirm the existence of nodal surfaces and eightfold degenerate nodal points in LaSb_(2).The intriguing multiple topological nodal structure might play a crucial role in giving rise to the large linear magnetoresistance.Our work renews the insights into the exotic topological phenomena in LaSb_(2). | Yuxi Qiao Fuyi Wang Huaiqiang Wang Zicheng Tao Zhicheng Jiang Zhengtai Liu Soohyun Cho Fayuan Zhang Qingkai Meng Wei Xia Yichen Yang Zhe Huang Jishan Liu Zhonghao Liu Zengwei Zhu Shan Qiao Yanfeng Guo Haijun Zhang Dawei Shen | 2024 | Science China(Physics,Mechanics & Astronomy)2024，67，4： | 0 |
| 14 | Pressure-tuning domain-wall chirality in noncentrosymmetric magnetic Weyl semimetal CeAlGe显示文摘Topological magnetic Weyl semimetals have been proposed to host controllable chiral domain walls which bear a great prospect in device applications. To exploit them in applications, it is important to have a proper way to tune and manipulate these domain walls. One possible means is through magnetoelastic coupling. The involvement of rare earth in the lately proposed RAl X(R =rare earth, X = Si and Ge) family magnetic Weyl semimetals may provide such a platform. Here we present the transport and thermodynamic properties of Ce Al Ge under hydrostatic pressure. We find that pressure enhances the antiferromagnetic exchange in Ce Al Ge but essentially retains its magnetic structure. A large topological Hall effect with a pronounced loop shape is observed within the magnetically ordered state, and it splits into two regions under pressure. Such an unusual electromagnetic response is inferred to be a consequence of chiral magnetic domain walls. The unprecedented concomitance of its evolution under pressure and the reentrance of antiferromagnetic order strongly suggest the capability of switching on/off this electromagnetic response in noncentrosymmetric magnetic Weyl semimetals via magnetoelastic coupling. | Xiaobo He Yuke Li Hai Zeng Zengwei Zhu Shiyong Tan Yongjun Zhang Chao Cao Yongkang Luo | 2023 | Science China(Physics,Mechanics & Astronomy)2023，66，3： | 0 |
| 15 | Surface superconductivity in the type Ⅱ Weyl semimetal TaIrTe4显示文摘The search for unconventional superconductivity in Weyl semimetal materials is currently an exciting pursuit,since such superconducting phases could potentially be topologically non-trivial and host exotic Majorana modes.The layered material TaIrTe4 is a newly predicted time-reversal invariant type II Weyl semimetal with the minimum number of Weyl points.Here,we report the discovery of surface superconductivity in Weyl semimetal TaIrTe4.Our scanning tunneling microscopy/spectroscopy(STM/STS)visualizes Fermi arc surface states of TaIrTe4 that are consistent with the previous angle-resolved photoemission spectroscopy results.By a systematic study based on STS at ultralow temperature,we observe uniform superconducting gaps on the sample surface.The superconductivity is further confirmed by electrical transport measurements at ultralow temperature,with an onset transition temperature(Tc)up to 1.54 K being observed.The normalized upper critical field h?(T/Tc)behavior and the stability of the superconductivity against the ferromagnet indicate that the discovered superconductivity is unconventional with the p-wave pairing.The systematic STS,and thickness-and angular-dependent transport measurements reveal that the detected superconductivity is quasi-1D and occurs in the surface states.The discovery of the surface superconductivity in TaIrTe4 provides a new novel platform to explore topological superconductivity and Majorana modes. | Ying Xing Zhibin Shao Jun Ge Jiawei Luo Jinhua Wang Zengwei Zhu Jun Liu Yong Wang Zhiying Zhao Jiaqiang Yan David Mandrus Binghai Yan Xiong-Jun Liu Minghu Pan Jian Wang | 2020 | National Science Review2020，7，3： | 0 |
| 16 | Strong Pauli paramagnetic effect in the upper critical field of KCa2Fe4As4F2显示文摘Recently, 12442 system of Fe-based superconductors has attracted considerable attention owing to its unique double-Fe As-layer structure. A steep increase in the in-plane upper critical field with cooling has been observed near the superconducting transition temperature, Tc, in KCa2Fe4As4F2 single crystals. Herein, we report a high-field investigation on upper critical field of this material over a wide temperature range, and both out-of-plane(H∥c, Hc2c) and in-plane(H∥ab, Hc2ab ) directions have been measured.A sublinear temperature-dependent behavior is observed for the out-of-plane Hc2c , whereas strong convex curvature with cooling is observed for the in-plane Hc2ab . Such behaviors could not be described by the conventional Werthamer-Helfand-Hohenberg(WHH) model. The data analysis based on the WHH model by considering the spin aspects reveals a large Maki parameter α=9,indicating that the in-plane upper critical field is affected by a very strong Pauli paramagnetic effect. | Teng Wang Chi Zhang LiangCai Xu JinHua Wang Shan Jiang ZengWei Zhu ZhaoSheng Wang JiaNan Chu JiaXin Feng LingLing Wang Wei Li Tao Hu XiaoSong Liu Gang Mu | 2020 | Science China(Physics,Mechanics & Astronomy)2020，63，2： | 0 |
| 17 | La_(2)Rh_(3+δ)Sb_(4):a new ternary superconducting rhodium-antimonide显示文摘Rhodium-containing compounds offer a fertile playground to explore novel materials with superconductivity(SC)and other fantastic electronic correlation effects.A new ternary rhodium-antimonide La_(2)Rh_(3)+δSb_(4)(δ≈1/8)has been synthesized by a Bi-flux method.It crystallizes in the orthorhombic La_(2)Rh_(3+δ)Sb_(4)-like structure,with the space group Pnma(No.62).The crystalline structure appears as stacking the two-dimensional RhSb_(4)-and RhSb_(5)-polyhedra networks along b axis,and the La atoms embed in the cavities of these networks.Band structure calculations confirm it as a multi-band metal with a van-Hove singularity like feature at the Fermi level,whose density of states are mainly of Rh-4d and Sb-5p characters.The calculations also imply that the redundant Rh acts as charge dopant.SC is observed in this material with onset transition at Ton c≈0.8 K.Ultra-low temperature magnetic susceptibility and specific heat measurements suggest that it is an s-wave type-II superconductor.Our work may also imply that the broad Ln_(2)Tm_(3+δ)Sb_(4)(Ln=rare earth,Tm=Rh,Ir)family may host new material bases where new superconductors,quantum magnetism and other electronic correlation effects could be found. | Kangqiao Cheng Wei Xie Shuo Zou Huanpeng Bu Jin-Ke Bao Zengwei Zhu Hanjie Guo Chao Cao Yongkang Luo | 2022 | Materials Futures2022，1，4： | 0 |
| 18 | Magnetic-field-induced metal-insulator quantum phase transition in CaFeAsF near the quantum limit显示文摘The quantum limit, where only the lowest Landau level is occupied by electrons, can be achieved under a high magnetic field when the Landau level splitting is comparable with the Fermi energy. The rather small Fermi pockets and Fermi energy in CaFeAsF reported recently make this compound a good candidate for investigating the electrical transport near the quantum limit.Here, we report high-field experiments up to 65 T on a single-crystalline CaFeAsF, which shows a metal-insulator quantum phase transition tuned by the out-of-plane magnetic field. The obtained critical exponent zν through the finite-size scaling analysis is very close to 4/3. This transition is closely associated with the evolution of electronic states approaching the quantum limit.The resistivity behaviors as a function of field and temperature were evaluated based on Adams-Holstein theory(A-H theory).Moreover, the in-plane component of the field, which does not affect the transport behavior in the classical region, suppressed the magnetoresistance near the quantum limit. | YongHui Ma Gang Mu Tao Hu ZengWei Zhu ZhuoJun Li Wei Li QiuCheng Ji Xuan Zhang LingLing Wang XiaoMing Xie | 2018 | Science China(Physics,Mechanics & Astronomy)2018，61，12： | 0 |
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