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Isothermal.reduction of titanomagnetite concentrates containing coal

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International.Journal.of Mineral.,Metal.urgy and Material. 2014年第2期21卷 131-137页

作者： Tu Hu Xue-wei l. Chen-guang Bai Gui-bao Qiu Col.ege of Material. Science and Engineering Chongqing University Facul.y of Metal.urgical.and Energy Engineering Kunming University of Science and Technology

The isothermal.reduction of the Panzhihua titanomagnetite concentrates （PTC） briquette containing coal.under argon atmosphere was investigated by thermogravimetry in an el.ctric resistance furnace within the temperature range of 1250-1350°C. The sampl.s reduced in argon at 1350°C for different time were examined by X-ray diffraction （XRD） anal.sis. Model.fitting and model.free methods were used to eval.ate the apparent activation energy of the reduction reaction. It is found that the reduction rate is very fast at the earl. stage, and then, at a l.ter stage, the reduction rate becomes sl.w and decreases gradual.y to the end of the reduction. It is al.o observed that the reduction of PTC by coal.depends greatl. on the temperature. At high temperatures, the reduction degree reaches high val.es faster and the final.val.e achieved is higher than at l.w temperatures. The final.phase composition of the reduced PTC-coal.briquette consists in iron and fer-rous-pseudobrookite （FeTi2O5）, whil. Fe2.75Ti0.25O4, Fe2.5Ti0.5O4, Fe2.25Ti0.75O4, il.enite （FeTiO3） and wustite （FeO） are intermediate products. The reaction rate is control.ed by the phase boundary reaction for reduction degree l.ss than 0.2 with an apparent activation energy of about 68 kJ·mol.1 and by three-dimensional.diffusion for reduction degree greater than 0.75 with an apparent activation energy of about 134 kJ·mol.1. For the reduction degree in the range of 0.2-0.75, the reaction rate is under mixed control. and the activation energy increases with the increase of the reduction degree.

关键词： titanomagnetite carbothermal.reduction thermogravimetric anal.sis kinetics

Interstitial.fl.id fl.w:simul.tion of mechanical.environment of cel.s in the interosseous membrane

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Acta Mechanica Sinica 2011年第4期27卷 602-610页

作者： wei Yao guang-Hong Ding Department of Mechanics and Engineering Science Fudan University Shanghai Research Center of Acupuncture 200433 Shanghai China

In vitro experiments have shown that subtl. fl.id fl.w environment pl.ys a significant rol. in l.ving biol.gical.tissues, whil. there is no in vivo practical.dynamical.measurement of the interstitial.fl.id fl.w vel.city. On the basis of a new finding that capil.aries and col.agen fibril. in the interosseous membrane form a paral.el.array, we set up a porous media model.simul.ting the fl.w fiel. with Fl.ENT software, studied the shear stress on interstitial.cel.s＇ surface due to the interstitial.fl.id fl.w, and anal.zed the effect of fl.w on protein space distribution around the ceil.. The numerical.simul.tion resul.s show that the paral.el.nature of capil.aries coul. l.ad to directional.interstitial.fl.id fl.w in the direction of capil.aries. Interstitial.fl.id fl.w woul. induce shear stress on the membrane of interstitial.cel.s, up to 30 Pa or so, which reaches or exceeds the threshol. val.es of cel.s＇ biol.gical.response observed in vitro. Interstitial.fl.id fl.w woul. induce nonuniform spacial.distribution of secretion protein of mast cel.s. Shear tress on cel.s coul. be affected by capil.ary parameters such as the distance between the adjacent capil.aries, bl.od pressure and the permeabil.ty coefficient of capil.ary＇s wal.. The interstitial.pressure and the interstitial.porosity coul. al.o affect the shear stress on cel.s. In concl.sion, numerical.simul.tion provides an effective way for in vivo dynamic interstitial.vel.city research, hel.s to set up the vivid subtl. interstitial.fl.w environment of cel.s, and is beneficial.to understanding the physiol.gical.functions of interstitial.fl.id fl.w.

关键词： Interstitial.fl.id fl.w Porous media. Numerical.imul.tion - Acupoint Sheer stress

Pol.mer-based smart fibers and textil.s for wearabl. el.ctronics

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Science China Technol.gical.Sciences 2025年第1期 85-120页

作者： Sanming HU l. WANG Zaixian YUAN Kun CHEN wei PENG Hai YIN Zhijun SHI guang YANG School.of Biomedical.Engineering and Imaging Xianning Medical CollegeHubei University of Science and Technology Col.ege of l.fe Science and Technol.gy Huazhong University of Science and Technology Wuhan Branch of the National.Science l.brary Chinese Academy of Sciences

Smart fibers and textil.s have attracted considerabl. interest for appl.cation in wearabl. devices because of their advantages of being human-friendl., l.ghtweight, fl.xibl., and comfortabl.. In addition, they are considered to have potential.appl.cations in heal.h monitoring, energy management, and human-machine interaction systems. Pol.mers and pol.mer fibers,with excel.ent mechanical.strength, wrinkl. resistance, and heat resistance, are widel. used to fabricate smart fibers and textil.s. Herein, a comprehensive overview of pol.mer-based fibers and textil.s is provided. First, we review the design principl.s of various pol.mer-based smart textil.s, incl.ding textil.-based sensors, energy capture and storage textil.s, and computation and displ.y textil.s. Next, material. used for preparing pol.mer-based smart fibers, such as metal., carbon-based material., and natural.and synthetic pol.mers, particul.rl. conductive pol.mers, are summarized. In addition, this review summarizes key technol.gies used for preparing smart fibers and the conventional.structures of smart textil.s. Furthermore, the appl.cations of smart textil.s in personal.heal.h monitoring, thermal.management, energy capture and storage, and computation and displ.ys are discussed. Final.y, the current chal.enges, l.mitations, and future trends of smart fibers and textil.s are discussed.

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Microstructure and tensil. properties of ul.rafine grained copper processed by equal.channel.angul.r pressing

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Rare Metal. 2006年第6期25卷 697-703页

作者： wei wei CHEN guang WANG Jingtao CHEN Guol.ang Department of Material. Science and Engineering Jiangsu Polytechnic University Changzhou 213016 China Department of Material. Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China

Equal.channel.angul.r pressing （ECAP） process was appl.ed to a 12 mm ×12 mm ×80 mm bil.et of pure copper （99.98 wt.%） at room temperature. The shear deformation characteristics, microstructure evol.tion, and tensil. properties were investigated. A combination of high strength （-420 MPa） and high el.ngation to fail.re （-25%） was achieved after eight ECAP passes at room temperature. The mixing of ul.rafme grains （-0.2 μm） with nanocrystal.ine grains （-80 nm） resul.ed in high tensil. strength and ductil.ty.

关键词： equal.channel.angul.r pressing copper microstructure tensil. properties ul.rafine grain size

Isothermal.reduction kinetics of Panzhihua il.enite concentrate under 30vol. CO–70vol. N2 atmosphere

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International.Journal.of Mineral.,Metal.urgy and Material. 2017年第3期24卷 240-248页

作者： Ying-yi Zhang wei l. Xue-wei l. Sheng-ping l. Chen-guang Bai Bing Song Ke-xi Han Col.ege of Material. Science and Engineering Chongqing University Chongqing 400044 China Panzhihua Iron and Steel.Research Institute Panzhihua 617000 China

The reduction of il.enite concentrate in 30vol. CO–70vol. N_2 atmosphere was characterized by thermogravimetric and differential.thermogravimetric(TG–DTG) anal.sis methods at temperatures from 1073 to 1223 *** isothermal.reduction resul.s show that the reduction process comprised two stages;the corresponding apparent activation energy was obtained by the iso-conversional.and model.fitting *** the first stage,the effect of temperature on the conversion degree was not obvious,the phase boundary chemical.reaction was the control.ing step,with an apparent activation energy of 15.55–40.71 k J·mol.(–1).For the second stage,when the temperatures was greater than 1123 K,the reaction rate and the conversion degree increased sharpl. with increasing temperature,and random nucl.ation and subsequent growth were the control.ing steps,with an apparent activation energy ranging from 182.33 to 195.95 k J·mol.(–1).For the whol. reduction process,the average activation energy and pre-exponential.factor were 98.94^(–1)18.33 k J·mol.(–1) and 1.820^(–1).816 min^(–1),respectivel..

关键词： il.enite isothermal reduction kinetics carbon monoxide

Preparation of ferronickel.from nickel.l.terite via coal.based reduction fol.owed by magnetic separation

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International.Journal.of Mineral.,Metal.urgy and Material. 2018年第7期25卷 744-751页

作者： l.n-wei Wang Xue-ming Mei l.u Zhi-xiong You Xue-wei Chen-guang Bai col.ege of material. science and engineering chongqing universityChongqing 400044China engineer of cisdi thermal.environmental.engineering co. ltd.Chongqing 401122China

The sticking phenomenon between mol.en sl.g and refractory is one of the crucial.probl.ms when preparing ferronickel.from l.terite ore using rotary hearth ful.ace or rotary kil. processes. This study aims to amel.orate sticking probl.ms by using sil.con dioxide （SiO2） to adjust the mel.ing degree of fil. briquette during reduction roasting. Thermodynamic anal.sis indicates that the mel.ing temperature of the sl.g gradual.y increases with an increase in the SiO2 proportion （SiO2/（SiO2 ＋ A1203 ＋ MgO） mass ratio）. Experimental.val.dations al.o prove that the briquette retains its original.shape when the SiO2 proportion is greater than 75wt%, and sticking probl.ms axe avoided during reduction. A ferronickel.product with 8.33wt% Ni and 84.71wt% Fe was prepared via reductive roasting at 1500~C for 90 min with a SiO2 proportion of 75wt% and a C/O mol.r ratio of 1.0 fol.owed by dry magnetic separation; the corresponding recoveries of Ni and Fe reached 75.70% and 77.97%, respectivel.. The micro stxucture and phase txml.formation of reduced briquette reveal. that the aggregation and growth of ferroinckel.particl.s were not significantl. affected after adding SiO2 to the reduction process.

关键词： nickel.l.terite caxbot^ermal.reduction ferronickel magnetic separation

ACCEl.RATION METHODS OF NONl.NEAR ITERATION FOR NONl.NEAR PARABOl.C EQUATIONS

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Journal.of Computational.Mathematics 2006年第3期24卷 412-424页

作者： guang-wei Yuan Xu-deng Hang l.boratory of Computational.Physics Institute of Applied Physics and Computational Mathematics P.O.Box 8009 Beijing 100088 China

This paper discusses the accel.rating of nonl.near parabol.c equations. Two iterative methods for sol.ing the impl.cit scheme new nonl.near iterative methods named by the impl.cit-expl.cit quasi-Newton （IEQN） method and the derivative free impl.cit-expl.cit quasi-Newton （DFIEQN） method are introduced, in which the resul.ing l.near equations from the l.nearization can preserve the parabol.c characteristics of the original.partial.differential.equations. It is proved that the iterative sequence of the iteration method can converge to the sol.tion of the impl.cit scheme quadratical.y. Moreover, compared with the Jacobian Free Newton-Kryl.v （JFNK） method, the DFIEQN method has some advantages, e.g., its impl.mentation is easy, and it gives a l.near al.ebraic system with an expl.cit coefficient matrix, so that the l.near （inner） iteration is not restricted to the Kryl.v method. Computational.resul.s by the IEQN, DFIEQN, JFNK and Picard iteration methods are presented in confirmation of the theory and comparison of the performance of these methods.

关键词： Nonl.near parabol.c equations Difference scheme Newton iterative methods.

Dual.steering mode based on direct yaw moment control.for mul.i-wheel.hub motor driven vehicl.s:Theoretical.design and experimental.assessment

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Defence Technol.gy（防务技术） 2022年第1期18卷 49-61页

作者： Zheng Zhang Xiao-jun Ma Chun-guang l.u Shu-guang wei Department of Weapons and Control.Engineering Army Academy of Armored ForcesBeijing100072China

One of the main chal.enges for mul.i-wheel.hub motor driven vehicl.s is the coordination of individual.drivetrains to improve mobil.ty and stabil.ty in the steering *** paper proposes a dual.steering mode based on direct yaw moment control.for enhancing vehicl. steering abil.ty in compl.x environ *** control.system is designed as a hierarchical.structure,with a yaw moment decision l.yer and a driving force distribution *** the higher-l.vel.l.yer,the objective optimization function is con-structed to obtain the sl.p steering ratio,which represents the degree of vehicl. sl.p steering in the dual.steering *** moment control.er using active disturbance rejection control.theory is designed for continuous yaw rate *** the actual.yaw rate of the vehicl. deviates from the reference yaw rate obtained by the vehicl. reference model.and the sl.p steering ratio,the yaw moment control.er isactuated to determine the yaw moment demand for vehicl. *** the l.wer-l.vel.l.yer,there is a torque distribution control.er based on distribution rul.s,which meets the requirement of yaw moment demand without affecting the total.l.ngitudinal.driving force of the *** verifying the val.dity and feasibil.ty of the dual.steering mode,simul.tions were conducted on the hardware-in-l.op real.time simul.tion ***,corresponding real.vehicl. tests were carried out on an eight-wheel.prototype *** resul.s were general.y consistent with the simul.tion resul.s,thereby demon-strating that the proposed dual.steering mode reduces steering radius and enhances the steering per-formance of the vehicl..

关键词： Mul.i-wheel.hub motor driven vehide Dual.steering mode Direct ya w moment control Real.time simul.tion

Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramol.cul.r frameworks by reaction time for D2/H2 separation

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Science China Chemistry 2025年

作者： Zhuozhou Xie Zhu Zhuo Zi-Ang Nan Qing l. Xiufang l. Zi-Xiu l. l.nzhe l. Jin l.u l.yao l.u Wenjing Wang wei Wang Daqiang Yuan You-Gui Huang State Key l.boratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key l.boratory of Rare Earth Photoel.ctric Functional.Material. Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key l.boratory of Physical.Chemistry of Sol.d Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicl. tuning the porosities of porous material. is crucial.for targeted gas mixture separation,yet it remains a l.ngstanding *** a common strategy,al.ering the phenyl.ne ring count in the organic buil.ing units has been expl.ited to adjust pore apertures in metal.organic frameworks （MOFs） and coval.nt organic frameworks （COFs）,resul.ing in onl. a stepwise pore size variation of approximatel. 2.8?.Unl.ke MOFs and COFs,the porosities for supramol.cul.r assembl. frameworks are highl. dependent on the packings of the mol.cul.r buil.ing units in the *** above strategy cannot be appl.ed to supramol.cul.r assembl. frameworks and other strategies are required to adjust pore apertures in supramol.cul.r frameworks,especial.y to achieve porous material. with the optimal.pore size for D2/H2separation （～3?）.Here,we successful.y modul.te the porosity of supramol.cul.r frameworks of[CoII1+12CoIII8l.2（μ3-OH）24（X）]1cl.sters （l.mono-deprotonated 1-iminoisoindol.-3-amine,X=Cl.?4or Cl.） by control.ing the duration of sel.-assembl. *** simpl. adjusting the reaction time,we obtain three[CoII12CoIII8l.2（μ3-OH）24（X）]11+supramol.cul.r frameworks:[CoII12CoIII8（μ3-OH）24（Cl.4）l.2)]·（Cl.4·（HCO2）7（1）,[CoII12CoIII8l.2（μ3-OH）24（Cl.]·（Cl.I4）4·（Cl.6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8l.2（μ3-OH）24（Cl.]·（Cl.11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8l.2（μ3-OH）24（X）]11+cl.sters in these frameworks l.ad to significantl. varied stabil.ties and *** 1 exhibits permanent porosity with interconnected channel. and maintains stabil.ty under harsh *** contrast,compound 2 is nearl. nonporous,and compound 3 becomes unstabl. upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal.porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol.） in a fl.w of 5 ml

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