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Fabrication and magnetic properties of NiFe-ZnO nano-granular films

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Rare Metals 2013年第3期32卷 269-272页

作者： xue-Yun Zhou Dong-sheng Yao Faculty of Science Jiujiang University Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology Tianjin University

Excellent soft magnetic and high frequency prop- erties were obtained successfully in the （Ni75Fe25）x（ZnO）1-x granular films fabricated on the glass substrate by RF magnetron oblique sputtering. The microstructure, mag- netic and high frequency properties were investigated systematically. High resolution transmission electron micrographs show that the film consists of fcc Ni75Fe25 particles uniformly embedded in an amorphous insulating matrix ZnO with particle size a few nanometers. The （Ni75Fe25）x（ZnO）1-x films exhibit excellent soft magnetic properties in a widex range from 0.50 to 0.80 with coer- civity not exceeding 5 × 10^-4 T, which is ascribed to the exchange coupling between magnetic particles. Especially for the sample with x = 0.64, coercivities in hard and easy axes are 5.0 ×10^-5 and 3.6 × 10^-4 T, respectively, and the electric resistivity ρ reaches 1,790 μΩ.cm. The dependence of complex permeability u = u′- ju″on frequency f shows that the real part u′ is more than 130 below 500 MHz, and the ferromagnetic resonance fre- quency fr reaches 1.32 GHz, implying the promising for high frequency application.

关键词： Soft magnetic property Nano-granular thinfilms High frequency application

Soil formation in bauxite residue: The most promising way to large-scale and ecological disposal

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Journal of Central South University 2019年第2期26卷 265-267页

作者： xue sheng-guo School of Metallurgy and Environment Central South University

Aluminum is an important basic raw material for national economic *** alumina industry has been expanding rapidly due to the increasing demand for *** residue is a highly alkaline solid by-product generated when alumi... 详细信息

关键词： bauxite residue promising way ecological disposal

Recovery of titanium and vanadium from titanium–vanadium slag obtained by direct reduction of titanomagnetite concentrates

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Rare Metals 2022年第5期41卷 1688-1696页

作者： xue-Jie Liu de-sheng Chen Jing-Long Chu Wei-Jing Wang Yong-Li Li Tao Qi National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemistry and Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

A process of NaOH molten salt roasting-water leaching to treat titanium-vanadium slag obtained by direct reduction of titanomagnetite concentrates was investigated.X-ray diffraction(XRD), scanning electron microscopy(SEM) equipped with energy dispersive spectroscopy(EDS), and thermogravimetry-differential scanning calorimetry(TG-DSC) techniques were used to characterize the samples. The results show that anosovite(Mg_(x)Ti_(3-x)O_(5))and clinopyroxene [Ca(Ti,MgAl)(SiAl)_(2)O_(6)] are the major phases of titanium-vanadium slag. In the NaOH molten salt roasting process, titanium is converted to intermediate product Na_(2)TiO_(3) and vanadium is converted to water-soluble vanadate. The response surface methodology(RSM) was used to optimize the roasting process conditions. NaOH to slag mass ratio(N/S) and roasting temperature are the main influential factors. Under the optimal roasting conditions,i.e., roasting temperature of 550℃, N/S of 1.20, and roasting time of 80 min, the conversions of titanium and vanadium are 96.5 % and 93.0 %, respectively. In the water leaching process, Na_(2)TiO_(3) is converted to amorphous structure of H_(2)TiO_(3) since Na^(+)is exchanged with H^(+). Up to 93.0 % vanadium is leached out under the optimal leaching conditions. Titanium and vanadium in the titanium-vanadium slag can be separated and then recovered.

关键词： Recovery Titanium-vanadium slag Roasting Water leaching Titanomagnetite concentrates

Local Influence Analysis for Semiparametric Reproductive Dispersion Nonlinear Models

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Acta Mathematicae Applicatae Sinica 2012年第1期28卷 75-90页

作者： xue-dong CHEN Nian-sheng TANG xue-ren WANG department of Statistics Yunnan UniversityKunming 650091China

The present paper proposes a semiparametric reproductive dispersion nonlinear model （SRDNM） which is an extension of the nonlinear reproductive dispersion models and the semiparameter regression models. Maximum penalized likelihood estimates （MPLEs） of unknown parameters and nonparametric functions in SRDNM are presented. Assessment of local influence for various perturbation schemes are investigated. Some local influence diagnostics are given. A simulation study and a real example are used to illustrate the proposed methodologies.

关键词： local influence analysis maximum penalized likelihood estimate nonlinear reproductive dispersionmodels semiparametric regression model

Pollen dispersal in traditional processing of buckwheat and its application in agricultural archaeology

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Science China Earth Sciences 2018年第12期61卷 1792-1803页

作者： Yang LIU xue SHANG Pengfei sheng Guoding SONG Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China department of Archaeology and Anthropology University of Chinese Academy of SciencesBeijing 100049China

Pollen, as an important index of the paleoenvironment and ancient human agricultural activities, is also one of the significant indicators for research on buckwheat agriculture. In order to test buckwheat pollen dispersal during each crop processing stage, we applied traditional processing simulation experiments of buckwheat crops in a modern village, to collect aerial pollen and perform statistical analysis. The result has shown that the distribution of buckwheat pollen in residential areas is closely related to human processing behaviour. Among all the processing procedures, pollen release rate is highest in the threshing and the sieving stages. The redistribution and burial of pollen during crop processing is an important reason for the prominent increase of crop pollen concentration in the cultural layer. Not only can it indicate the cultivation and processing behaviour of humans but also provide a basis for identifying the crop processing remains in archaeological sites and assessing the intensity of agricultural activities.

关键词： Buckwheat Crop processing Pollen dispersal Agricultural activities Agricultural archaeology

Optimized use of MgO flux in the agglomeration of high-chromium vanadium–titanium magnetite

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International Journal of Minerals,Metallurgy and Materials 2015年第4期22卷 371-380页

作者： Jue Tang Man-sheng Chu Xiang-xin xue School of Material and Metallurgy Northeastern University

The optimized use of MgO flux in the agglomeration of high-chromium vanadium-titanium magnetite was investigated system- atically through sinter and pellet experiments. MgO was added in the form of magnesite. When the content of MgO in the sinter was in- creased from 1.95wt% to 2.63wt%, the low-temperature reduction degradation index increased from 80.57% to 82.71%. When the content of MgO in the pellet was increased from 1.14wt% to 2.40wt%, the reduction swelling index decreased from 15.2% to 8.6%; however, the com- pressive strength of the oxidized pellet decreased dramatically and it was 1985 N with an MgO content of 1.14wt%. This compressive strength does not satisfy the requirements for blast-furnace production. When all of the aforementioned results were taken into account, the sinter with a high MgO content （2.63wt%） matching the pellet with a low MgO content （less than 1.14wt%） was the rational burden structure for smelting high-chromium vanadium-titanium magnetite in blast furnaces.

关键词： magnetite ore pellets magnesia agglomeration burden sintering

Receptivity of hypersonic boundary layer due to fast-slow acoustics interaction

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Acta Mechanica Sinica 2015年第6期31卷 899-909页

作者： Jun Gao Ji-sheng Luo xue-Song Wu department of Mechanics Tianjin University department of Mathematics Imperial College London

The objective of receptivity is to investigate the mechanisms by which external disturbances generate unsta- ble waves. In hypersonic boundary layers, a new receptivity process is revealed, which is that fast and slow acoustics through nonlinear interaction can excite the second mode near the lower-branch of the second mode. They can generate a sum-frequency disturbance though nonlinear interaction, which can excite the second mode. This receptivity process is generated by the nonlinear interaction and the nonparal- lel nature of the boundary layer. The receptivity coefficient is sensitive to the wavenumber difference between the sumfrequency disturbance and the lower-branch second mode. When the wavenumber difference is zero, the receptivity coefficient is maximum. The receptivity coefficient decreases with the increase of the wavenumber difference. It is also found that the evolution of the sum-frequency disturbance grows linearly in the beginning. It indicates that the forced term generated by the sum-frequency disturbance resonates with the second mode.

关键词： Hypersonic boundary layer · Receptivity·Nonlinear interaction · Acoustic

Pressure evolution in shock-compacted granular media

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Petroleum Science 2023年第6期20卷 3736-3751页

作者： Jia-Rui Li Jun-sheng Zeng Kun xue State Key Laboratory of Explosive Science and Technology Beijing Institute of TechnologyBeijing100081China Institute of Applied Physics and Computational Mathematics Beijing100094China

The pressure evolution associated with the transient shock-induced infiltration of gas flow through granular media consisting of mobile particles is numerically investigated using a coupled Eulerian–Lagrangian *** coupling between shock compaction and interstitial flow has been revealed.A distinctive two-stage diffusing pressure field with deflection occurring at the tail of the compaction front is found,with corresponding spikes in both gaseous velocity and temperature profiles emerging within the width of the compaction *** compaction front,together with the deflection pressure,reaches a steady state during the later *** analytical prediction of the steady deflection pressure that considers the contributions of porosity and the non-isothermal effect is *** isothermal single-phase method we developed,combining the porosity jump condition across the compaction front,shows consistent pressure evolution with the non-isothermal CMP-PIC one under weak shock strength and low column ***,the microscale mechanism governing the formation of not only pressure deflection but also gaseous velocity and temperature spikes within the width of the compaction front has been *** aforementioned evolutions of the flow field are shown to arise from the nozzling effects associated with the particle-scale variations in the volume fraction.

关键词： Shock compaction Pressure evolution Transport in porous media Transient gas infiltration Mobile granular column

Zeolite powder addition to improve the performance of submerged gravitation-filtration membrane bioreactor

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Journal of Environmental Sciences 2006年第2期18卷 242-247页

作者： HE sheng-bing xue Gang KONG Hai-nan School of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 China School of Environmental Science and Engineering.Donghua University Shanghai 200051 China

In this study, the effect of zeolite powder addition on submerged membrane bioreactor （SMBR） on membrane permeability, and the removals for COD, NH3-N, TN were investigated. Through the parallel operation of control and test systems, it was found that the zeolite powder addition could alleviate the ultra-filtration membrane fouling and enhance the membrane permeability. On the basis of experimental investigations, a concept of ＂protection coating layer＂ was proposed to illustrate the phenomenon of UF membrane fouling. In addition, the removal for COD in test system was more stable, a little higher compared to the control system. Due to the combination of nitrification and ion exchange, a more excellent removal for NH3-N in test system was obtained regardless of influent NH3-N loading rate. It was also found that a mean 25% higher TN removal took place in the test system, and ion exchange and simultaneous nitrification and de-nitrification were analyzed to be main factors. During the stable operation period, the SOURs of test zeolite powder added sludge and control activated sludge were measured to be 75 mgO2/（gMLVSS, h） and 24 mgO2/（gMLVSS, h） respectively, it meant that the zeolite powder addition could enhance the microorganism activity significantly.

关键词： submerged gravitation-filtration membrane bioreactor performance zeolite powder membrane fouling microorganism activity