铁精矿内配生物质直接还原的研究

采用碳中性、清洁、可再生的生物质作为还原剂,对铁精矿内配生物质直接还原及其还原行为进行研究。研究结果表明：铁精矿内配生物质在直接还原前期快速产生CO、H₂、C_mH_n、CO₂、H₂O等,在反应罐内形成最高可达16 k Pa的压力,有利于生物质热解后在铁精矿颗粒表面及孔隙内沉积生物质炭及其原位气化,生成H₂和CO,并与铁氧化物还原反应构成耦合作用,显著促进了铁氧化物低温快速还原。与传统的未反应核模型不同,新生的金属铁向气流方向迁移和聚集,形成了纤维状的金属铁晶须。提高还原温度和延长还原时间能够加快铁晶须的迁移和生长,在还原温度为1 040℃和还原时间为50 min的条件下,海绵铁金属化率高达97.21%,铁晶须的宽度达4～10μm。     

同步还原焙烧法降低循环流化床固硫粉煤灰三氧化硫并回收铁精矿实验

以重庆安稳电厂高烧失量、高SO3和铁质量分数的循环流化床固硫粉煤灰为例,运用同步还原焙烧—湿法弱磁选铁精矿方法对粉煤灰进行协同降硫和选铁实验:以粉煤灰中未燃尽碳作还原剂而无须额外添加,在一次还原焙烧工序中同步实现了粉煤灰中SO3载体矿物无水石膏(Ca SO4)的分解以及赤铁矿(Fe2O3)的磁化;采用水淬法冷却,湿法弱磁选铁精矿,在水淬和湿法磁选阶段Ca SO4分解产物Ca S水化生成粉煤灰的有益组分Ca(OH)2;另一水化产物H2S气体亦予以回收利用。研究结果表明:循环流化床固硫粉煤灰经900℃下还原焙烧15 min,再经水淬快速冷却、湿法弱磁选铁精矿,可获得总铁回收率49.8%、品位52.9%的铁精矿;处理后的粉煤灰烧失量和SO3质量分数分别降至5.3%和1.32%,达到GB/T 1596—2005"用于水泥和混凝土中的粉煤灰"中的相应指标。     

流化床内生产碳化铁的动力学行为

在小型流化床内,利用COCO2H2的混合气体还原铁矿粉,用气体分析仪对尾气成分进行检测,并与初始气氛相比较,得出还原速度和产品组成随时间的变化规律;应用缩核模型,对流化床内的铁矿石还原的动力学行为进行了描述,确定了反应的速度控制步骤·当初始气氛为60%CO+20%CO2+20%H2时,在550～700℃范围内表观活化能为34.7kJ/mol;初始气氛为48%CO+32%CO2+20%H2时,在550～650℃范围内表观活化能为35.9kJ/mol·在此基础上得到影响铁矿石还原的动力学因素     

磨浮铜精矿流化床氧化动力学

本文采用SO_2气体吸收(电导电位自动记录)方法研究了磨浮铜精矿在800、900、1000℃下流化床氧化动力学,应用气-固多相反应理论和流化床两相模型建立了反应的数学模型,计算了气泡相和乳相中模型的各种参数和床层中O_2的浓度分布,研究表明:硫化亚铜矿的氧化反应主要在乳相中进行。反应速率主要由界面反应所控制,产物层中气体扩散的阻力较小,床层下部O_2的消耗比较迅速。     

铁精矿内配某生物质高温高压热解及其还原行为研究

以生物质为还原剂,在温度为1 040℃、压力为30 kPa下对铁精矿内配生物质热解气化及其还原行为进行研究。研究结果表明：初期热解产生了酚类等大分子碳氢氧化合物液相,并与铁精矿形成了焦油包裹体,显著迟滞了生物质挥发分的释放;外配水和铁精矿中的晶格氧促进了大分子碳氢氧化合物逐步氧化为酮类、酸类化合物,并最终转化为CO和H₂等还原性气体;铁精矿还原生成了铁晶须,部分形成了碳铁化合物,实现了铁氧化物的高效快速还原,入炉50 min时,金属化率达96.72%。     

含硼铁精矿选择性还原-选分新工艺的实验研究

针对现有含硼铁精矿硼铁分离工艺所存在的弊端,提出了含硼铁精矿选择性还原-选分新工艺,并通过热力学分析和实验室研究进行了验证.研究表明:对于辽宁凤城Fe和B2O3质量分数分别为5605%和386%的含硼铁精矿,最佳的选择性还原-选分工艺参数如下:配碳比08~10,还原温度1275~1300℃,还原时间不小于20min,还原煤粒度为-0075mm,分选时的磁场强度为50mT.得到的选分产物为高金属化率的金属铁粉,可进一步处理用于钢铁生产;选分尾矿为高品位的含硼资源,可作为硼工业的优质原料.     

FeO高温气—固还原动力学研究

在１１８０－１３３０℃，通过测定浮氏体颗粒在流化床中被ＣＯ还原的反应速度，并应用未反应核模型处理数据，得到还原反应速度方程和表观活化能，研究表明氧离子在还原后生成铁层中的固相扩散为还原过程的限制性环节，但是过程呈现明显的两段速度特征，在反应后期，由于生成铁相发生晶格转变，使氧离子在铁层中的扩散更为困难，帮反应的活化能增大，反应速度明显减慢。     

铁精矿冷固球团矿在工业性回转窑内的还原行为

研究了铁精矿冷固球团矿在工业性回转窑内的还原行为。研究结果表明：由于复合粘结剂集粘结、催化和还原诸功能于一体，使冷固球团矿按均质反应模型还原；铁氧化物催化作用及粘结剂的热致聚合效应，使还原反应前期固体桥键得到强化，在还原反应中期粘结剂促进金属桥键形成和长大，从而使冷固球团矿具有良好的还原性及还原过程中具有足够的机械强度，消除了低温还原粉化，是一种优质的直接还原炉料。     

FeO高温气－固还原动力学研究

在１１８０～１３３０℃，通过测定浮氏体颗粒在流化床中被ＣＯ还原的反应速度，并应用未反应核模型处理数据，得到还原反应速度方程和表观活化能．研究表明氧离子在还原后生成铁层中的团相扩散为还原过程的限制性环节，但是过程呈现明显的两段速度特征．在反应后期（ｆ＞６５％左右），由于生成铁相发生晶格转变，使氧离子在铁层中的扩散更为困难，故反应的活化能增大，反应速度明显减慢．通过扫描电镜（ＳＥＭ）对生成铁层结构变化的研究，也进一步证实了这一点．     

苯氧化制顺丁烯二酸酐的反应动力学

用V_2O_5为活性组分的SD固体催化剂,在等温积分反应器中研究了文题。实验在工业生产操作条件下进行,用氧化还原动力学模型进行参数估值,给出了苯氧化反应动力学参数,该参数可用于反应器模拟计算。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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