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Ion beam figuring of continuous phase plates based on the frequency filtering process

Mingjin XU,Yifan DAI,Xuhui XIE,Lin ZHOU,Shengyi LI,Wenqiang PENG

《机械工程前沿(英文)》 2017年 第12卷 第1期   页码 110-115 doi: 10.1007/s11465-017-0430-5

摘要:

Ion beam figuring (IBF) technology is an effective technique for fabricating continuous phase plates (CPPs) with small feature structures. This study proposes a multi-pass IBF approach with different beam diameters based on the frequency filtering method to improve the machining accuracy and efficiency of CPPs during IBF. We present the selection principle of the frequency filtering method, which incorporates different removal functions that maximize material removal over the topographical frequencies being imprinted. Large removal functions are used early in the fabrication to figure the surface profile with low frequency. Small removal functions are used to perform final topographical correction with higher frequency and larger surface gradient. A high-precision surface can be obtained as long as the filtering frequency is suitably selected. This method maximizes the high removal efficiency of the large removal function and the high corrective capability of the small removal function. Consequently, the fast convergence of the machining accuracy and efficiency can be achieved.

关键词: ion beam figuring (IBF)     continuous phase plates (CPPs)     machining accuracy     machining efficiency     frequency filtering process    

纳米测量仪器和纳米加工技术

姚骏恩

《中国工程科学》 2003年 第5卷 第1期   页码 33-37

摘要:

纳米科技是当今国际上的一个热点。文章对纳米科技作了简要介绍, 纳米测量和加工是纳米科技中的一个不可缺少的重要组成部分。叙述了发展纳米测量和纳米加工技术的两个主要途径:一是发展传统技术,主要是电子显微术以及最近发展起来的聚焦离子束(FIB)- 电子束数控加工中心;二是创造新的测量仪器,建立新原理和新方法,介绍了国内外电子显微镜和扫描探针显微镜这两类纳米测量分析仪器的发展、应用和生产现状。指出我国电子显微仪器和扫描探针显微镜的开发和生产面临困境,应尽快建立和加强自己的电子显微仪器和扫描探针显微镜等纳米测量和纳米加工设备制造产业,并列入国家科技发展规划。

关键词: 纳米科技     纳米测量     电子显微镜     扫描探针显微镜     聚焦离子束-电子束装置     仪器生产    

Recent advances in micro- and nano-machining technologies

Shang GAO, Han HUANG

《机械工程前沿(英文)》 2017年 第12卷 第1期   页码 18-32 doi: 10.1007/s11465-017-0410-9

摘要:

Device miniaturization is an emerging advanced technology in the 21st century. The miniaturization of devices in different fields requires production of micro- and nano-scale components. The features of these components range from the sub-micron to a few hundred microns with high tolerance to many engineering materials. These fields mainly include optics, electronics, medicine, bio-technology, communications, and avionics. This paper reviewed the recent advances in micro- and nano-machining technologies, including micro-cutting, micro-electrical-discharge machining, laser micro-machining, and focused ion beam machining. The four machining technologies were also compared in terms of machining efficiency, workpiece materials being machined, minimum feature size, maximum aspect ratio, and surface finish.

关键词: micro machining     cutting     electro discharge machining (EDM)     laser machining     focused ion beam (FIB)    

两种典型结构强流自箍缩二极管技术研究

杨海亮,邱爱慈,孙剑锋,高屹,苏兆锋,李静雅,孙凤举,梁天学,尹佳辉,丛培天,黄建军,任书庆

《中国工程科学》 2009年 第11卷 第11期   页码 70-78

摘要:

主要介绍了箍缩聚焦二极管和自箍缩离子束二极管的研究进展。重点介绍了近几年发展的阳极杆箍缩聚焦二极管的理论模拟和实验结果,在“闪光二号”加速器和2 MV脉冲功率驱动源上进行了阳极杆箍缩二极管实验,二极管输出电压1.8~2.1 MV,电流40~60 kA,脉宽(FWHM)50~60 ns,1 m处的脉冲X剂量约20~30 mGy,焦斑直径约1 mm,X射线最高能量1.8 MeV。在“闪光二号”加速器上开展了高功率离子束的产生和应用研究,给出了自箍缩反射离子束二极管的结构和工作原理,实验获得的离子束峰值电流~160 kA,离子的峰值能量~500 keV,开展了利用高功率质子束轰击19F靶产生6~7 MeV准单能脉冲γ射线,模拟X射线热—力学效应等应用基础研究。

关键词: 阳极杆箍缩二极管     离子束二极管     X射线     高功率离子束     箍缩     聚焦    

Advancing ion-exchange membranes to ion-selective membranes: principles, status, and opportunities

《环境科学与工程前沿(英文)》 2023年 第17卷 第2期 doi: 10.1007/s11783-023-1625-0

摘要:

● IEM ion/ion selectivities of charge, valence, & specific ion are critically assessed.

关键词: Ion-exchange membranes     Selectivity     Separations    

Scaling up of cluster beam deposition technology for catalysis application

《化学科学与工程前沿(英文)》 2021年 第15卷 第6期   页码 1360-1379 doi: 10.1007/s11705-021-2101-7

摘要: Many research works have demonstrated that the combination of atomically precise cluster deposition and theoretical calculations is able to address fundamental aspects of size-effects, cluster-support interactions, and reaction mechanisms of cluster materials. Although the wet chemistry method has been widely used to synthesize nanoparticles, the gas-phase synthesis and size-selected strategy was the only method to prepare supported metal clusters with precise numbers of atoms for a long time. However, the low throughput of the physical synthesis method has severely constrained its wider adoption for catalysis applications. In this review, we introduce the latest progress on three types of cluster source which have the most promising potential for scale-up, including sputtering gas aggregation source, pulsed microplasma cluster source, and matrix assembly cluster source. While the sputtering gas aggregation source is leading ahead with a production rate of ~20 mg·h–1, the pulsed microplasma source has the smallest physical dimensions which makes it possible to compact multiple such devices into a small volume for multiplied production rate. The matrix assembly source has the shortest development history, but already show an impressive deposition rate of ~10 mg·h–1. At the end of the review, the possible routes for further throughput scale-up are envisaged.

关键词: nanoparticle     cluster     cluster beam deposition     magnetron sputtering     heterogeneous catalysis    

Alumina modified sodium vanadate cathode for aqueous zinc-ion batteries

《能源前沿(英文)》   页码 775-781 doi: 10.1007/s11708-023-0902-8

摘要: Aqueous zinc-ion batteries (ZIBs) have great prospects for widespread application in massive scale energy storage. By virtue of the multivalent state, open frame structure and high theoretical specific capacity, vanadium (V)-based compounds are a kind of the most developmental potential cathode materials for ZIBs. However, the slow kinetics caused by low conductivity and the capacity degradation caused by material dissolution still need to be addressed for large-scale applications. Therefore, sodium vanadate Na2V6O16·3H2O (NVO) was chosen as a model material, and was modified with alumina coating through simple mixing and stirring methods. After Al2O3 coating modification, the rate capability and long-cycle stability of Zn//NVO@Al2O3 battery have been significantly improved. The discharge specific capacity of NVO@Al2O3 reach up to 228 mAh/g (at 4 A/g), with a capacity reservation rate of approximately 68% after 1000 cycles, and the Coulombic efficiency (CE) is close to 100%. As a comparison, the capacity reservation rate of Zn//NVO battery is only 27.7%. Its superior electrochemical performance is mainly attributed to the Al2O3 coating layer, which can increase zinc-ion conductivity of the material surface, and to some extent inhibit the dissolution of NVO, making the structure stable and improving the cyclic stability of the material. This paper offers new prospects for the development of cathode coating materials for ZIBs.

关键词: cathodes     aqueous zinc-ion batteries     sodium vanadate     alumina     coating    

Processing parameter optimization of fiber laser beam welding using an ensemble of metamodels and MOABC

《机械工程前沿(英文)》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0703-5

摘要: In fiber laser beam welding (LBW), the selection of optimal processing parameters is challenging and plays a key role in improving the bead geometry and welding quality. This study proposes a multi-objective optimization framework by combining an ensemble of metamodels (EMs) with the multi-objective artificial bee colony algorithm (MOABC) to identify the optimal welding parameters. An inverse proportional weighting method that considers the leave-one-out prediction error is presented to construct EM, which incorporates the competitive strengths of three metamodels. EM constructs the correlation between processing parameters (laser power, welding speed, and distance defocus) and bead geometries (bead width, depth of penetration, neck width, and neck depth) with average errors of 10.95%, 7.04%, 7.63%, and 8.62%, respectively. On the basis of EM, MOABC is employed to approximate the Pareto front, and verification experiments show that the relative errors are less than 14.67%. Furthermore, the main effect and the interaction effect of processing parameters on bead geometries are studied. Results demonstrate that the proposed EM-MOABC is effective in guiding actual fiber LBW applications.

关键词: laser beam welding     parameter optimization     metamodel     multi-objective    

Application of consistent geometric decomposition theorem to dynamic finite element of 3D composite beam

Iman FATTAHI, Hamid Reza MIRDAMADI, Hamid ABDOLLAHI

《结构与土木工程前沿(英文)》 2020年 第14卷 第3期   页码 675-689 doi: 10.1007/s11709-020-0625-4

摘要: Analyzing static and dynamic problems including composite structures has been of high significance in research efforts and industrial applications. In this article, equivalent single layer approach is utilized for dynamic finite element procedures of 3D composite beam as the building block of numerous composite structures. In this model, both displacement and strain fields are decomposed into cross-sectional and longitudinal components, called consistent geometric decomposition theorem. Then, the model is discretized using finite element procedures. Two local coordinate systems and a global one are defined to decouple mechanical degrees of freedom. Furthermore, from the viewpoint of consistent geometric decomposition theorem, the transformation and element mass matrices for those systems are introduced here for the first time. The same decomposition idea can be used for developing element stiffness matrix. Finally, comprehensive validations are conducted for the theory against experimental and numerical results in two case studies and for various conditions.

关键词: composite beam     dynamic finite element     degrees of freedom coupling     experimental validation     numerical validation    

Vanadium oxide cathode with synergistic engineering of calcium-ion intercalation and polyaniline coatingfor high performance zinc-ion batteries

《化学科学与工程前沿(英文)》 2023年 第17卷 第9期   页码 1244-1253 doi: 10.1007/s11705-022-2293-5

摘要: Vanadium oxides as cathode for zinc-ion batteries have attracted much attention because of their high theoretical capacity, flexible layered structure and abundant resources. However, cathodes are susceptible to the collapse of their layered structure and the dissolution of vanadium after repeated long cycles, which worsen their capacities and cycling stabilities. Herein, a synergistic engineering of calcium-ion intercalation and polyaniline coating was developed to achieve the superior electrochemical performance of vanadium pentoxide for zinc-ion batteries. The pre-intercalation of calcium-ion between vanadium pentoxide layers as pillars increase the crystal structure’s stability, while the polyaniline coating on the cathodes improves the conductivity and inhibits the dissolution of vanadium. This synergistic engineering enables that the battery system based-on the polyaniline coated calcium vanadate cathode to deliver a high capacity of 406.4 mAh·g−1 at 1 A·g−1, an ultralong cycle life over 6000 cycles at 10 A·g−1 with 93% capacity retention and high-rate capability. The vanadium oxide cathode with synergistic engineering of calcium-ion intercalation and polyaniline coating was verified to effectively improve the electrochemical performance of zinc-ion batteries.

关键词: zinc-ion battery     CaV8O20     polyaniline coating     synergistic engineering     high capacity     long durability    

Experimental and numerical analysis of beam to column joints in steel structures

Gholamreza ABDOLLAHZADEH, Seyed Mostafa SHABANIAN

《结构与土木工程前沿(英文)》 2018年 第12卷 第4期   页码 642-661 doi: 10.1007/s11709-017-0457-z

摘要: The behaviors such as extreme non-elastic response, constant changes in roughness and resistance, as well as formability under extreme loads such as earthquakes are the primary challenges in the modeling of beam-to-column connections. In this research, two modeling methods including mechanical and neural network methods have been presented in order to model the complex hysteresis behavior of beam-to-column connections with flange plate. First, the component-based mechanical model will be introduced in which every source of transformation has been shown only with geometrical and material properties. This is followed by the investigation of a neural network method for direct extraction of information out of experimental data. For the validation of behavioral curves as well as training of the neural network, the experiments were carried out on samples with real dimensions of beam-to-column connections with flange plate in the laboratory. At the end, the combinational modeling framework is presented. The comparisons reveal that the combinational modeling is able to display the complex narrowed hysteresis behavior of the beam-to-column connections with flange plate. This model has also been successfully employed for the prediction of the behavior of a newly designed connection.

关键词: beam to column connections     experiments     component method     neural network model     combinational modeling    

disrupting chemicals from water through urethane functionalization of microfiltration membranes via electron beam

《环境科学与工程前沿(英文)》 2023年 第18卷 第4期 doi: 10.1007/s11783-024-1805-6

摘要:

● Urethane functionalities created on PES membranes via electron beam irradiation.

关键词: Surface functionalization     Electron beam irradiation     Microfiltration     Endocrine disrupting chemicals    

Ion-imprinted silica gel and its dynamic membrane for nickel ion removal from wastewaters

Jiehui Zeng, Jianxian Zeng, Hu Zhou, Guoqing Liu, Zhengqiu Yuan, Jian Jian

《化学科学与工程前沿(英文)》 2020年 第14卷 第6期   页码 1018-1028 doi: 10.1007/s11705-020-1915-z

摘要: An ion-imprinted sorbent (IIP) was prepared by using Ni as template, 3-[2-(2-aminoethylamino) ethylamino] propyl-trimethoxysilane as functional monomer, and silica gel as carrier. The adsorption performance of IIP towards Ni was investigated. IIP showed a higher adsorption capacity than that of non-imprinted sorbent, and it also exhibited high selectivity for Ni in the presence of Cu and Zn ions. Then, IIP was used to form a dynamic membrane onto the surface of ceramic membrane for treatment of electroplating wastewater containing Ni . Compared with ceramic membrane, IIP dynamic membrane had much higher steady membrane flux, and also rejected Ni to obtain a lower concentration of Ni in the permeate fluid. Perhaps it is suitable for future practice applications.

关键词: ion-imprinted     nickel ion     dynamic membrane     adsorption    

软夹芯夹层梁最大弯曲正应力的计算

郝景新,刘文金,吴新凤

《中国工程科学》 2014年 第16卷 第4期   页码 92-95

摘要:

最大弯曲正应力是衡量夹层梁弯曲性能的重要参数之一,本文推导出了将软夹芯夹层梁等效成等 截面均质单层梁计算最大弯曲正应力的方法,并在此基础上进行三点弯曲试验的算例研究。结果表明:修正单层梁理论与层合梁理论计算的结果是一致的。当破坏载荷与夹层梁横截面的尺寸一定时,随着芯层与总厚度比的增加,修正单层梁理论计算的最大正应力值逐渐增加,而单层梁理论计算的结果为一恒定值。最大弯曲正应力修正公式的建立为夹层梁的工程应用提供理论基础。

关键词: 夹层梁     弯曲正应力     单层梁理论     弯曲特性    

Highly selective metal recovery from spent lithium-ion batteries through stoichiometric hydrogen ion

Weiguang Lv, Xiaohong Zheng, Li Li, Hongbin Cao, Yi Zhang, Renjie Chen, Hancheng Ou, Fei Kang, Zhi Sun

《化学科学与工程前沿(英文)》 2021年 第15卷 第5期   页码 1243-1256 doi: 10.1007/s11705-020-2029-3

摘要: Spent lithium-ion battery recycling has attracted significant attention because of its importance in regard to the environment and resource importance. Traditional hydrometallurgical methods usually leach all valuable metals and subsequently extract target meals to prepare corresponding materials. However, Li recovery in these processes requires lengthy operational procedures, and the recovery efficiency is low. In this research, we demonstrate a method to selectively recover lithium before the leaching of other elements by introducing a hydrothermal treatment. Approximately 90% of Li is leached from high-Ni layered oxide cathode powders, while consuming a nearly stoichiometric amount of hydrogen ions. With this selective recovery of Li, the transition metals remain as solid residue hydroxides or oxides. Furthermore, the extraction of Li is found to be highly dependent on the content of transition metals in the cathode materials. A high leaching selectivity of Li (>98%) and nearly 95% leaching efficiency of Li can be reached with LiNi Co Mn O . In this case, both the energy and material consumption during the proposed Li recovery is significantly decreased compared to traditional methods; furthermore, the proposed method makes full use of H to leach Li . This research is expected to provide new understanding for selectively recovering metal from secondary resources.

关键词: recycling     spent LIBs     selective recovery     hydrothermal treatment    

标题 作者 时间 类型 操作

Ion beam figuring of continuous phase plates based on the frequency filtering process

Mingjin XU,Yifan DAI,Xuhui XIE,Lin ZHOU,Shengyi LI,Wenqiang PENG

期刊论文

纳米测量仪器和纳米加工技术

姚骏恩

期刊论文

Recent advances in micro- and nano-machining technologies

Shang GAO, Han HUANG

期刊论文

两种典型结构强流自箍缩二极管技术研究

杨海亮,邱爱慈,孙剑锋,高屹,苏兆锋,李静雅,孙凤举,梁天学,尹佳辉,丛培天,黄建军,任书庆

期刊论文

Advancing ion-exchange membranes to ion-selective membranes: principles, status, and opportunities

期刊论文

Scaling up of cluster beam deposition technology for catalysis application

期刊论文

Alumina modified sodium vanadate cathode for aqueous zinc-ion batteries

期刊论文

Processing parameter optimization of fiber laser beam welding using an ensemble of metamodels and MOABC

期刊论文

Application of consistent geometric decomposition theorem to dynamic finite element of 3D composite beam

Iman FATTAHI, Hamid Reza MIRDAMADI, Hamid ABDOLLAHI

期刊论文

Vanadium oxide cathode with synergistic engineering of calcium-ion intercalation and polyaniline coatingfor high performance zinc-ion batteries

期刊论文

Experimental and numerical analysis of beam to column joints in steel structures

Gholamreza ABDOLLAHZADEH, Seyed Mostafa SHABANIAN

期刊论文

disrupting chemicals from water through urethane functionalization of microfiltration membranes via electron beam

期刊论文

Ion-imprinted silica gel and its dynamic membrane for nickel ion removal from wastewaters

Jiehui Zeng, Jianxian Zeng, Hu Zhou, Guoqing Liu, Zhengqiu Yuan, Jian Jian

期刊论文

软夹芯夹层梁最大弯曲正应力的计算

郝景新,刘文金,吴新凤

期刊论文

Highly selective metal recovery from spent lithium-ion batteries through stoichiometric hydrogen ion

Weiguang Lv, Xiaohong Zheng, Li Li, Hongbin Cao, Yi Zhang, Renjie Chen, Hancheng Ou, Fei Kang, Zhi Sun

期刊论文