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软磁复合材料硝酸钠钝化绝缘包覆新技术 Article

严密, 陈起明, 刘冬, 吴琛, 王健

《工程（英文）》 2023年第20卷第1期页码 134-142 doi: 10.1016/j.eng.2022.01.016

摘要：

本研究发明了制备FeSiAl软磁复合材料（SMC）的硝酸钠钝化绝缘包覆新技术。结合成分组成和显微结构分析，研究了不同pH条件下包覆层的生成规律，发现酸性NaNO₃溶液钝化形成的绝缘包覆层由Fe₂O₃、SiO₂、Al₂O₃和AlO(OH)组成。随着pH值升高，由于NO₃⁻的氧化能力减弱，Fe₂O₃转化为Fe₃O₄，而碱性NaNO₃溶液钝化形成Al₂O₃、AlO(OH)和SiO₂。进一步地，从热力学和动力学角度揭示了包覆层生长机理及其与FeSiAl SMC软磁性能的内在关联。通过调整钝化条件，可实现在50 kHz和100 mT测试条件下，有效磁导率为97.2、损耗为296.4 mW·cm⁻³的最优性能。

关键词：软磁复合材料表面钝化绝缘包覆技术生长机理磁性能

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Modeling and analysis of magnetic dipoles in weak magnetic field

WANG Zhaoxia, ZHANG Weimin, LIU Hongguang

《机械工程前沿（英文）》 2008年第3卷第2期页码 222-225 doi: 10.1007/s11465-008-0028-z

摘要： The magnetic leakage field distribution resulting from linear defects of a tube sample in the geomagnetic field is modeled according to the magnetic dipole theory. The formula to compute the normal component of the weak magnetic field is deduced based on the spatial distribution of the magnetic dipole. The shape and characteristics of the zero line (an important criterion for magnetic memory testing) of the normal field is analyzed under different longitudinal magnetizations. Results show that the characteristics of the zero line should be considered when the metal magnetic memory testing method is used to find and locate the defect.

关键词： geomagnetic theory important criterion magnetic leakage normal component

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graphene-based ternary nanocomposite for the magnetophotocatalytic reduction of CO2 with electrochemical performance

《化学科学与工程前沿（英文）》 2022年第16卷第10期页码 1438-1459 doi: 10.1007/s11705-022-2166-y

摘要： The development of CO₂ into hydrocarbon fuels has emerged as a green method that could help mitigate global warning. The novel structured photocatalyst is a promising material for use in a photocatalytic and magneto-electrochemical method that fosters the reduction of CO₂ by suppressing the recombination of electron−hole pairs and effectively transferring the electrons to the surface for the chemical reaction of CO₂ reduction. In our study, we have developed a novel-structured AgCuZnS₂–graphene–TiO₂ to analyze its catalytic activity toward the selective evolution of CO₂. The selectivity of each nanocomposite substantially enhanced the activity of the AgCuZnS₂–graphene–TiO₂ ternary nanocomposite due to the successful interaction, and the selectivity of the final product was improved to a value 3 times higher than that of the pure AgCuZnS₂ and 2 times higher than those of AgCuZnS₂–graphene and AgCuZnS₂–TiO₂ under ultra-violet (UV)-light (λ = 254 nm) irradiation in the photocatalytic process. The electrochemical CO₂ reduction test was also conducted to analyze the efficacy of the AgCuZnS₂–graphene–TiO₂ when used as a working electrode in laboratory electrochemical cells. The electrochemical process was conducted under different experimental conditions, such as various scan rates (mV·s^–1), under UV-light and with a 0.07 T magnetic-core. The evolution of CO₂ substantially improved under UV-light (λ = 254 nm) and with 0.07 T magnetic-core treatment; these improvements were attributed to the facts that the UV-light activated the electron-transfer pathway and the magnetic core controlled the pathway of electron-transmission/prevention to protect it from chaotic electron movement. Among all tested nanocomposites, AgCuZnS₂–graphene–TiO₂ absorbed the CO₂ most strongly and showed the best ability to transfer the electron to reduce the CO₂ to methanol. We believe that our newly-modeled ternary nanocomposite opens up new opportunities for the evolution of CO₂ to methanol through an electrochemical and photocatalytic process.

关键词： ternary nanocomposite photocatalytic electrochemical CO₂ reduction UV-light magnetic core

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Rare-earth separation based on the differences of ionic magnetic moment via quasi-liquid strategy

《化学科学与工程前沿（英文）》页码 1584-1594 doi: 10.1007/s11705-022-2189-4

摘要： The separation of rare earth elements is particularly difficult due to their similar physicochemical properties. Based on the tiny differences of ionic radius, solvent extraction has been developed as the “mass method” in industry with hundreds of stages, extremely intensive chemical consumption and large capital investments. The differences of the ionic magnetic moment among rare earths are greater than that of ionic radius. Herein, a novel method based on the large ionic magnetic moment differences of rare earth elements was proposed to promote the separation efficiency. Rare earths were firstly dissolved in the ionic liquid, then the ordering degree of them was improved with the Z-bond effect, and finally the magnetic moment differences between paramagnetic and diamagnetic rare earths in quasi-liquid system were enhanced. Taking the separation of Er/Y, Ho/Y and Er/Ho as examples, the results showed that Er(III) and Ho(III) containing ionic liquids had obvious magnetic response, while ionic liquids containing Y(III) had no response. The separation factors of Er/Y and Ho/Y were achieved at 9.0 and 28.82, respectively. Magnetic separation via quasi-liquid system strategy provides a possibility of the novel, green, and efficient method for rare earth separation.

关键词： rare earth element different magnetic moment magnetic separation ionic liquid

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Rotating magnetic beacons magnetic field strength size in SAGD

Bing TU, Desheng LI, Enhuai LIN, Bin LUO, Jian HE, Lezhi YE, Jiliang LIU, Yuezhong WANG

《机械工程前沿（英文）》 2010年第5卷第4期页码 446-449 doi: 10.1007/s11465-010-0113-y

摘要： Rotation magnetic beacons magnetic field strength is very important to drill parallel horizontal twin wells in steam assisted gravity drainage (SAGD). This paper analyzes a small magnet with a diameter of 25.4 mm. At each end, there is a length of 12.6 mm with permanent magnet, and in the middle, there is a length of 78 mm with magnetic materials. The magnetic field strength generated by the magnetic material of 1J12, 1J50, and 1J79 is analyzed, respectively. ANSOFT software is used to simulate the magnetic field strength generated by different magnetic materials above, which also be tested through experimental methods. The comparison of the simulation and experimental results show that experimental and simulation results are basically consistent, and the results can meet the specific requirements of engineering applications.

关键词： rotating magnetic beacons steam assisted gravity drainage (SAGD) ANSOFT

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Synthesis of magnetic carbonaceous acid derived from waste garlic peel for biodiesel production via esterification

《能源前沿（英文）》 doi: 10.1007/s11708-022-0836-6

摘要： Waste biomass-supported magnetic solid acids have particular advantages in catalyst separation. First, a novel magnetic carbonaceous catalyst was synthesized from waste garlic peel (GP) via in situ impregnation before conducting carbonization at 450–600°C and sulfonation at 105°C. The physical and chemical properties of the synthesized catalysts were characterized. It was found that the magnetism of the catalyst increased with the carbonization temperature. The optimized catalyst, carbonized at 600°C (C600-S), possessed an excellent magnetization value of 12.5 emu/g, with a specific surface area of 175.1 m²/g, a pore volume of 0.16 cm³/g, and an acidic property of 0.74 mmol/g -SO₃H density. By optimizing the esterification conditions to produce biodiesel, an oleic acid conversion of 94.5% was achieved at w(catalyst dosage) = 10% (w is mass fraction), a molar ratio of n(methanol): n(oleic acid) = 10: 1 (n is the amount of substance), and a reaction for 4 h at 90°C. Further, for catalyst regeneration, it was found that sulfuric acid treatment was more effective for improving the esterification activity than solvent washing, with which a conversion of more than 76% was achieved after the third run.

关键词： garlic peel (GP) magnetic carbonaceous acid esterification biodiesel

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Magnetostriction varieties and stress relief caused by pulsed magnetic field

Zhipeng CAI, Xinjie DUAN, Jian LIN, Haiyan ZHAO

《机械工程前沿（英文）》 2011年第6卷第3期页码 354-358 doi: 10.1007/s11465-011-0123-4

摘要：

Magnetostriction is investigated to evaluate the stress relief caused by pulsed magnetic field treatment, because this physical property is closely associated with residual stress. Magnetostriction of different stressed samples is measured in this paper. The stress variations caused by pulsed magnetic treatment are also compared. It is found that magnetostriction variations are closely associated with stress changes. Thermodynamic potential is used to find the relationship between them. Based on several assumptions, we find that the product of magnetostriction amplitude and stress magnitude is nearly a constant during magnetic field treatment, which is valuable for stress relief evaluation and optimizing processing parameters. This conclusion is testified by stress measurements, and the calculated values are in accordance with the experiment results.

关键词： magnetostriction pulsed magnetic field treatment stress relief

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Inexpensive synthesis of a high-performance Fe

Nadir Abbas, Godlisten N. Shao, Syed M. Imran, Muhammad S. Haider, Hee Taik Kim

《化学科学与工程前沿（英文）》 2016年第10卷第3期页码 405-416 doi: 10.1007/s11705-016-1579-x

摘要： A sol-gel technique has been developed for the synthesis of a magnetite-silica-titania (Fe O -SiO -TiO ) tertiary nanocomposite with improved photocatalytic properties based on the use of inexpensive titania and silica precursors. The exceptional photocatalytic activity of the resulting materials was demonstrated by using them to photocatalyze the degradation of methylene blue solution. The best formulation achieved 98% methylene blue degradation. An interesting feature of the present work was the ability to magnetically separate and reuse the catalyst. The efficiency of the catalyst remained high during two reuses. The synthesized nanomaterials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, ultra-violet-visible spectroscopy, diffuse reflectance spectroscopy, and thermogravimetric analysis. XRD analysis revealed the formation of multicrystalline systems of cubic magnetite and anatase titania crystals. SEM and TEM characterization revealed well-developed and homogeneously dispersed particles of size less than 15 nm. FTIR spectra confirmed the chemical interaction of titania and silica. It was further noticed that the optical properties of the prepared materials were dependent on the relative contents of their constituent metal oxides.

关键词： sol-gel photocatalysis magnetic recovery TiO₂ Fe₃O₄ SiO₂

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Synergistic scale inhibition of polyaspartic acid composite with magnetic field

LIU Zhenfa, WANG Yanji, GAO Yuhua, ZHANG Lihui

《化学科学与工程前沿（英文）》 2007年第1卷第3期页码 261-265 doi: 10.1007/s11705-007-0047-z

摘要： Polyaspartic acid (PASP) composite, a scale inhibitor, was prepared from PASP, itaconic acid–acrylic acid–acrylic ester (IA-AA-AE) terpolymer and 2-phosphonobutane- 1,2,4-tricarboxylic acid (PBTCA). The scale inhibition of PASP composite and the effect of its synergism with a magnetic field on scale inhibition were investigated. Calcium carbonate crystals in scale samples were characterized by means of SEM and XRD. The static and dynamic experiments show that the chelating function of PASP composite for Ca can be enhanced by synergism with a magnetic field. Under Ca 650 mg/L, HCO 1,300 mg/L and PASP composite 4 mg/L, the scale inhibition rate of PASP composite in magnetic water can increase by 10% in static state and by 20% in dynamic experiments. Scanning electron microscope (SEM) and X-ray diffraction (XRD) results show that calcite and aragonite can be completely transformed into vaterite by using PASP composite.

关键词： synergism magnetic PBTCA dynamic acid–acrylic acid–acrylic

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Continuous size fractionation of magnetic nanoparticles by using simulated moving bed chromatography

Carsten-Rene Arlt, Dominik Brekel, Stefan Neumann, David Rafaja, Matthias Franzreb

《化学科学与工程前沿（英文）》 2021年第15卷第5期页码 1346-1355 doi: 10.1007/s11705-021-2040-3

摘要： The size fractionation of magnetic nanoparticles is a technical problem, which until today can only be solved with great effort. Nevertheless, there is an important demand for nanoparticles with sharp size distributions, for example for medical technology or sensor technology. Using magnetic chromatography, we show a promising method for fractionation of magnetic nanoparticles with respect to their size and/or magnetic properties. This was achieved by passing magnetic nanoparticles through a packed bed of fine steel spheres with which they interact magnetically because single domain ferro-/ferrimagnetic nanoparticles show a spontaneous magnetization. Since the strength of this interaction is related to particle size, the principle is suitable for size fractionation. This concept was transferred into a continuous process in this work using a so-called simulated moving bed chromatography. Applying a suspension of magnetic nanoparticles within a size range from 20 to 120 nm, the process showed a separation sharpness of up to 0.52 with recovery rates of 100%. The continuous feed stream of magnetic nanoparticles could be fractionated with a space-time-yield of up to 5 mg/(L∙min). Due to the easy scalability of continuous chromatography, the process is a promising approach for the efficient fractionation of industrially relevant amounts of magnetic nanoparticles.

关键词： magnetic chromatography simulated moving bed chromatography magnetic nanoparticles size fractionation

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A new miniaturized engine based on thermomagnetic effect of magnetic fluids

Lujun ZHOU, Yimin XUAN, Qiang LI, Wenlei LIAN

《能源前沿（英文）》 2009年第3卷第2期页码 160-166 doi: 10.1007/s11708-009-0018-9

摘要： A new engine system, essentially consisting of a permanent NdFeB magnet, a kerosene-based magnetic fluid and a rotor, is proposed based on the thermomagnetic effect of a temperature-sensitive magnetic fluid. The rotor was driven by the thermal convection of the magnetic fluid in the presence of a homogeneous external magnetic field. A digital camera was used to record the rotation speed of the rotor to investigate the performance of the engine system under varying conditions such as heat load, heat sink temperature, and magnetic field distribution. The peak angle velocity obtained for the rotor was about 2.1 rad/min. The results illustrate that the rotation speed of the rotor increases as the input heat load increases, or as the heat sink temperature decreases. The performance of the motor is considerably influenced by the magnetic field imposed. Therefore, the performance of such an engine can be controlled conveniently by changing the external magnetic field and/or the temperature distribution in the fluid.

关键词： magnetic fluid thermomagnetic effect engine

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oxidation capacity of ammonia-oxidizing archaeon originated from wastewater: Utilizing low-density static magnetic

《环境科学与工程前沿（英文）》 2021年第15卷第5期 doi: 10.1007/s11783-020-1375-1

摘要：

• AOA’s ammonia oxidizing capacity was enhanced under moderate magnetic field.

关键词： Ammonia-oxidizing archaeon Ammonia oxidation Magnetic field Magnetotaxis Heredity

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Magnetic confinement fusion: a brief review

Chuanjun HUANG, Laifeng LI

《能源前沿（英文）》 2018年第12卷第2期页码 305-313 doi: 10.1007/s11708-018-0539-1

摘要： Fusion energy is considered to be the ultimate energy source, which does not contribute to climate change compared with conventional fossil fuel. It is massive compared with unconventional renewable energy and demonstrates fewer safety features compared with unconventional fission energy. During the past several decades, never-ceasing efforts have been made to peacefully utilize the fusion energy in various approaches, especially inertial confinement and magnetic confinement. In this paper, the main developments of magnetic confinement fusion with emphasis on confinement systems as well as challenges of materials related to superconducting magnet and plasma-facing components are reviewed. The scientific feasibility of magnetic confinement fusion has been demonstrated in JET, TFTR, JT-60, and EAST, which instigates the construction of the International Thermonuclear Experimental Reactor (ITER). A fusion roadmap to DEMO and commercial fusion power plant has been established and steady progresses have been made to achieve the ultimate energy source.

关键词： fusion energy magnetic confinement tokamak structural material superconducting magnet

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Fabrication of magnetic multi-template molecularly imprinted polymer composite for the selective and

《环境科学与工程前沿（英文）》 2021年第15卷第5期 doi: 10.1007/s11783-021-1395-5

摘要：

• Magnetic multi-template molecularly imprinted polymer composite was synthesized.

关键词： Tetracyclines Removal Adsorption Molecularly imprinted polymer Magnetic graphene oxide

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Application of metal magnetic memory test in failure analysis and safety evaluation of vessels

Yiliang ZHANG, Song YANG, Xuedong XU

《机械工程前沿（英文）》 2009年第4卷第1期页码 40-48 doi: 10.1007/s11465-009-0003-3

摘要： Metal magnetic memory test (MMMT), which is a new subject in the field of nondestructive examination, can determine regions of stress concentration by testing the distribution of the magnetic field of metal structures so as to effectively diagnose premature defects. MMMT and other test methods are applied in the study to put a propylene purifier of a temperature-jump accident and a leaked ammonia vessel through safety evaluation. Results are as follows: The margin of safety declines after the purifier is overburnt; several stress concentrations are observed within the overburnt area and the level of stress concentration rises after one-month operation; and overpressure operation of the purifier must be strictly avoided and carefully monitored during later operation. Cracks are observed on the ammonia vessel after one year’s service. Extremely high residual stress is the primary cause of cracks. After four years in service, the residual stresses existing in the area of the base metal and weld zone are still greater than 0.5 , which results in numerous cracks due to stress corrosion. From the MMMT result of the ammonia vessel’s defects, it can be seen that the derivative of magnetic density (d p/d ) is an important reference variable. Within the 31 leakage points, 67.7% of them whose dHp/dx values are more than 10, and 96.8% of them whose dHp/dx values are more than 8.

关键词： Metal magnetic memory test (MMMT) nondestructive testing (NDT) residual stress propylene purifier ammonia vessel

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标题作者时间类型操作

软磁复合材料硝酸钠钝化绝缘包覆新技术

严密, 陈起明, 刘冬, 吴琛, 王健

期刊论文

Modeling and analysis of magnetic dipoles in weak magnetic field

WANG Zhaoxia, ZHANG Weimin, LIU Hongguang

期刊论文

graphene-based ternary nanocomposite for the magnetophotocatalytic reduction of CO2 with electrochemical performance

期刊论文

Rare-earth separation based on the differences of ionic magnetic moment via quasi-liquid strategy

期刊论文

Rotating magnetic beacons magnetic field strength size in SAGD

Bing TU, Desheng LI, Enhuai LIN, Bin LUO, Jian HE, Lezhi YE, Jiliang LIU, Yuezhong WANG

期刊论文

Synthesis of magnetic carbonaceous acid derived from waste garlic peel for biodiesel production via esterification

期刊论文

Magnetostriction varieties and stress relief caused by pulsed magnetic field

Zhipeng CAI, Xinjie DUAN, Jian LIN, Haiyan ZHAO

期刊论文

Inexpensive synthesis of a high-performance Fe

Nadir Abbas, Godlisten N. Shao, Syed M. Imran, Muhammad S. Haider, Hee Taik Kim

期刊论文

Synergistic scale inhibition of polyaspartic acid composite with magnetic field

LIU Zhenfa, WANG Yanji, GAO Yuhua, ZHANG Lihui

期刊论文

Continuous size fractionation of magnetic nanoparticles by using simulated moving bed chromatography

Carsten-Rene Arlt, Dominik Brekel, Stefan Neumann, David Rafaja, Matthias Franzreb

期刊论文

A new miniaturized engine based on thermomagnetic effect of magnetic fluids

Lujun ZHOU, Yimin XUAN, Qiang LI, Wenlei LIAN

期刊论文

oxidation capacity of ammonia-oxidizing archaeon originated from wastewater: Utilizing low-density static magnetic

期刊论文

Magnetic confinement fusion: a brief review

Chuanjun HUANG, Laifeng LI

期刊论文

Fabrication of magnetic multi-template molecularly imprinted polymer composite for the selective and

期刊论文

Application of metal magnetic memory test in failure analysis and safety evaluation of vessels

Yiliang ZHANG, Song YANG, Xuedong XU

期刊论文

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