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Effect of crystallization on purity of volatile metallic magnesium prepared from a one-step multi-region condensation process under vacuum condition

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Journal of Magnesium and Alloys 2022年第11期10卷 3281-3287页

作者： Bin Yang Dong Liang neng xiong Yang Tian Baoqiang Xu Yongnian Dai The State Key Laboratory of Complex Non-ferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China National Engineering Laboratory for Vacuum Metallurgy Kunming University of Science and TechnologyKunming 650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China IME Institute of Process Metallurgy and Metal Recycling RWTH Aachen UniversityAachen 52056Germany

We hereby report a green and simple volatilization-condensation process to prepare high-purity magnesium in different crystal forms under vacuum condition. This method can be also used for the analysis of other metals, which can be separated by the same concept. In addition, Mg condensation is a very fast process, and the corresponding easy growth of the Mg crystals is promoted when the concentration of magnesium vapor is raised. From the view of crystallization, ultrafast crystal growth of high-purity magnesium is a barrier-free and orderly process. Interestingly, different condensed forms of Mg obtained via this ultrafast volatilization-condensation process are showing different purities. The distinct morphological formation of Mg in different condensed form is probably attributed to the differences of surface energy change of Mg during the condensation process.

关键词： Mg Purity Vacuum Condensation Crystallization

Comparative evaluation of energy and resource consumption for vacuum carbothermal reduction and Pidgeon process used in magnesium production

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Journal of Magnesium and Alloys 2022年第3期10卷 756-767页

作者： Yang Tian Lipeng Wang Bin Yang Yongnian Dai Baoqiang Xu Fei Wang neng xiong State Key Laboratory of Complex Nonferrous Metal Resources Clear Utilization Kunming University of Science and TechnologyKunmingPR China National Engineering Laboratory for Vacuum Metallurgy Kunming University of Science and TechnologyKunmingPR China Key Laboratory of Vacuum Metallurgy for Nonferrous Metal of Yunnan Province Kunming University of Science and TechnologyKunmingPR China School of Metallurgy and Energy Engineering Kunming University of Science and TechnologyKunmingPR China

With the fast development of the application of magnesium based alloys,the demand for primary magnesium is increasing dramatically all over the *** Pidgeon process is the most widely used process for producing magnesium in China,but suffers from problems such as high energy,resource consumption and environmental *** the process of vacuum carbothermal reduction to produce magnesium(VCTRM)has attracted more and more attention as its advantages,but it has not been well-practiced in industrial applications and there also is no comprehensive and quantitative analysis of this *** study quantified the flows of resource and energy for the Pidgeon process and the VCTRM process,then compared and analyzed these two processes with each other from three *** VCTRM process results in 63.14%and 69.16%lower of non-renewable mineral resources and energy consumptions when compared to the Pidgeon process,***,the low energy consumption(2.675 tce vs.8.681 tce)and material to magnesium ratio(2.953:1 vs.6.429:1)of the VCTRM process,which lead to lower greenhouse gas(GHG)emissions(8.777 t vs.26.337 t)and solid waste generation(0.522 t vs.5.465 t)with a decrease of 66.67%and 90.45%,*** indicate that the VCTRM process is a more environmentally friendly process for magnesium production with high efficiency but low cost and low pollution,and it shows a good potential to be industrialized in the future after solving the bottleneck problem of the reverse reaction.

关键词： Magnesium production Vacuum carbothermal reduction process Pidgeon process Energy and resource consumption Greenhouse gas emissions.

Experimental and computational investigation of transonic speed

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Chinese Journal of Aeronautics 2021年第1期34卷 32-43页

作者： Yang TAO neng xiong Xiaobing WANG Jun LIN Zhiyong LIU Shang MA Junqiang WU High Speed Aerodynamic Institute China Aerodynamics Research and Development CenterMianycmg 621000China

The influence of the wing-tip vortex of leading aircraft on energy savings,quantified by formation aerodynamic force fraction of the following aircraft,is studied at transonic speed for a matrix of leading aircraft’s vortex *** research model adopts the hybrid formation of medium and large *** leading aircraft is scaled by 2.1%,and the following aircraft is scaled by 1.4%.An aerodynamic benefit "map"is developed to determine the optimum location of the following aircraft relative to the leading aircraft wake and to compare with experimental results,thus validating the use of CFD for the formation flight at cruising *** response surface model of aerodynamic gain effect relative to formation parameters is established via numerical calculation and wind tunnel *** optimal formation parameters and the setting criteria of the study model are *** show that the wing-tip vortex of large aircraft significantly increases lift and reduces drag on the medium-sized aircraft following *** drag slightly increases with the flow direction *** the increase of flow direction distance,the peak area moves from 15%of wing-tip overlap to 20%of *** addition,the maximum drag decreases about 16%,and the maximum lift increases about 12%.The lift drag ratio of the optimal position is increased by 27%,which is twice as large as that of the same scale ratio aircraft *** show that the increase of lift is mainly caused by the increase of suction peak and suction range.

关键词： CFD Formation flight Surfing aircraft vortices Wake vortex Wind tunnel test

A Study on a Magnesium-Based Layered Composite Used as a Flame Retardant for Phenolic Epoxy Resins

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Fluid Dynamics & Materials Processing 2022年第3期18卷 549-561页

作者： Hongxiang Liu neng xiong Songli Wang Wei Zhang Bo Yong National Engineering Laboratory for Vacuum Metallurgy Key Laboratory of Nonferrous Metals Vacuum Metallurgy of Yunnan ProvinceKunming650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China

The effects of a magnesium-based layered composite on the flammability of a phenolic epoxy resin(EP)are *** order to produce the required composite material,first,magnesium hydroxide,aluminum salt and deionized water are mixed into a reactor according to a certain proportion to induce a hydrothermal reaction;then,the feed liquid is filtered out using a solid-liquid separation procedure;finally,the material is dried and *** order to evaluate its effects on the flammability of the EP,first,m-phenylenediamine is added to EP and vacuum defoamation is performed;then,EP is poured into a polytetrafluoroethylene mold,cooled to room temperature and demoulded;finally,the magnesium-based layered composite is added to EP,and its flame retardance is characterized by thermogravimetric analysis,limiting oxygen index and cone *** X-ray diffraction patterns show that the baseline of magnesium-based layered composite is stable and the front shape is sharp and symmetrical when the molar ratio of magnesium to aluminium is 3.2:1;with the addition of magnesium-based layered composite,the initial pyrolysis temperature of EP of 10%,15%and 30%magnesium-based layered composite decreases to 318.2°C,317.9°C and 357.1°C,*** the reaction,the amount of residual carbon increases to 0.1%,3.45%and 8.3%,and the limiting oxygen index increases by 28.3%,29.1%and 29.6%,*** maximum heat release rate of cone calorimeter decreases *** optimum molar ratio of Mg:Al for green synthesis is 3.2:1,and the NO_(3)-intercalated magnesium-based layered composite has the best flame retardance properties.

关键词： Phenolic epoxy resin layered composite green synthesis flame retardance anion intercalation

Coupling Enhancement of THz Metamaterials Source with Parallel Multiple Beams

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Chinese Journal of Electronics 2023年第4期32卷 678-682页

作者： ZHANG Kaichun FENG Yuming ZHAO Xiaoyan HU Jincheng xiong neng GUO Sidou TANG Lin LIU Diwei THz Center School of Electronic Science and Engineering University of Electronic Science and Technology of China

In this paper, we propose a terahertz radiation source over the R-band(220–325 GHz) based on metamaterials(MTMs) structure and parallel multiple beams. The effective permittivity and permeability of the slow-wave structure can be obtained through the S-parameter retrieval approach, using numerical simulation. Additionally, the electromagnetic properties of the MTMs structure are analyzed, including the dispersion and the coupling impedance. Furthermore, we simulate the beamwave interaction of the backward oscillator(BWO) with MTMs structure and parallel multiple beams by 3-D particle-in-cell code. It is observed that parallel multiple beams can highly enhance the beam-wave interaction and greatly enlarge the output power. These results indicate that the saturated(peak) output power is approximately63W with the efficiency of roughly 6% at the operating frequency of 231 GHz, under the beam voltage of 35 kV and total current of 30 mA(6-beam) respectively. Meanwhile, the BWO can generate power of 10–80 W in the tunable frequency of 220–240 GHz.

关键词： Couplings Simulation Voltage Terahertz radiation Metamaterials Scattering parameters Impedance

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钢筋粘结滑移弯矩-转角计算模型

工程力学 2019年第12期36卷 98-105页

作者：熊能顾冬生江南大学环境与土木工程学院江苏无锡214122 水利部堤防安全与病害防治工程技术研究中心河南郑州450003

纵筋在梁-柱或基础-柱界面处滑移将使侧向变形出现显著的增加。该文在现有二折线型钢筋粘结滑移弯矩-转角骨架曲线基础上,提出了屈服点以及破坏点滑移转角计算方法,可以用于预测滑移造成的侧向变形。根据与相互独立的五批共24个圆柱试... 详细信息

纵筋在梁-柱或基础-柱界面处滑移将使侧向变形出现显著的增加。该文在现有二折线型钢筋粘结滑移弯矩-转角骨架曲线基础上,提出了屈服点以及破坏点滑移转角计算方法,可以用于预测滑移造成的侧向变形。根据与相互独立的五批共24个圆柱试验结果对比,其计算结果具有较高的精度。在OpenSees软件中用基于力的纤维单元与粘结滑移弯矩-转角模型,对不同圆柱低周反复试验进行数值模拟,发现该模型计算结果与试验结果吻合很好。进一步,对圆柱在地震波作用下的振动台试验进行时程分析,柱顶位移和柱底滑移变形都能得到很好的预测。进行参数分析,结果表明极限点滑移量在总变形中的占比约为30%~40%,该占比随轴压比增加而减小,随体积配箍率减小而减小。

关键词： RC圆柱粘结滑移弯矩-转角混凝土柱变形 OpenSees

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三维无缝工程地质建模系统的研制

岩土力学 2009年第8期30卷 2385-2391页

作者：徐能雄田红中国地质大学工程技术学院北京100083

在边界表示法的基础上,提出了无缝工程地质模型的概念,实现了基于模型线框架的无缝工程地质建模方法,研制了无缝建模系统(ROCKModel)。该系统包括3个部分:原始数据转换工具、实体建模工具与辅助工具,涉及剖分、插值、曲面求交等8个基本... 详细信息

在边界表示法的基础上,提出了无缝工程地质模型的概念,实现了基于模型线框架的无缝工程地质建模方法,研制了无缝建模系统(ROCKModel)。该系统包括3个部分:原始数据转换工具、实体建模工具与辅助工具,涉及剖分、插值、曲面求交等8个基本功能模块。在基本功能模块的基础上,提出并实现了形态复杂曲面的创建、构建模型线框架、界面编辑与重构、块体搜索、岩体质量三维分级等关键技术。该系统能够实现复杂地质对象与工程对象的无缝建模与可视化,并为数值模拟软件直接提供几何模型。

关键词：三维地质建模无缝工程地质模型系统设计与研制线框架边界表示法

适于岩体结构三维建模的非连续地层界面整体重构

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岩土工程学报 2007年第9期29卷 1361-1366页

作者：徐能雄田红于沭中国地质大学工程技术学院北京100083

在岩体结构三维建模中,利用分区块方法重构被复杂断层系统切割的非连续地层界面时,插值与裁剪计算量巨大、过程烦琐,且无法反映断层两侧地层的相关性。针对该问题,提出了一种非连续地层界面整体重构方法。首先在不考虑断层影响的条件下... 详细信息

在岩体结构三维建模中,利用分区块方法重构被复杂断层系统切割的非连续地层界面时,插值与裁剪计算量巨大、过程烦琐,且无法反映断层两侧地层的相关性。针对该问题,提出了一种非连续地层界面整体重构方法。首先在不考虑断层影响的条件下进行整体插值形成初始地层界面,并根据断层信息形成断层面;然后求出所有断层面与初始地层界面的交线,并以这些交线作为约束,重新进行剖分与插值形成原始地层界面;再利用局部迭代求交计算实际断层交线;最后通过比较法确定断层影响范围,利用离散光滑插值方法(DSI)进行局部调值,实现非连续地层界面的整体重构。

关键词：岩体结构三维建模断层非连续地层界面整体重构离散光滑插值

千岛湖次生林优势种幼苗光合特性及其对群落演替的指示意义

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浙江大学学报（理学版） 2011年第5期38卷 570-578页

作者：金则新熊能台州学院生态研究所浙江临海317000

利用LCA-4型便携式全自动光合测定仪,于2009年8月下旬晴朗天气,对千岛湖次生林优势种马尾松(Pinus massoniana)、苦槠(Castanopsis sclerophylla)、石栎(Lithocarpus glabra)、青冈(Cyclobalanopsis glauca)幼苗在林窗、林下2种生境中的光合生理生态特性进行了研究.结果表明:(1)在林窗中马尾松光合日进程为"单峰"曲线,其他3种均为"双峰"曲线,有明显光合"午休"现象.在林下这4种幼苗的光合日进程均为"单峰"曲线,但曲线平缓,峰值不明显.在林窗中青冈的日均Pn显著低于其他3物种,而在林下马尾松的日均Pn显著低于其余3物种.4个优势种的日均Pn在2种生境中均差异显著.(2)LCP、LSP、Amax、Rd均是马尾松最高,苦槠次之,青冈、石栎较低;青冈、石栎的AQY显著高于马尾松和苦槠,苦槠的AQY也显著高于马尾松.(3)在林窗中,青冈Fm最高,与其他3种均差异显著;Fv/Fm为马尾松最高,显著高于其他3物种.这说明马尾松属强阳性树种,苦槠为阳性树种,青冈和石栎具有较强的耐荫性,随着进展演替,群落郁闭度的增大,马尾松、苦槠将逐渐退出群落,而青冈和石栎将成为群落演替顶极阶段的优势种.

关键词：千岛湖优势种幼苗光合特性荧光参数