镇静钢铝含量控制

一般以铝作为钢的终脱氧济。对细晶粒钢要求钢中铝含量大于0.02％,对深冲铝镇静钢要求钢中铝含量在0.04～0.07％。传统的加铝方法是在出钢过程中将铝块随钢流加入钢包内,这种加铝方法缺点是:铝烧损大,回收率低,钢中残铝含量不稳定。 为了提高和稳定铝的回收率以满足不同钢种的要求,人们一直在探索新的加铝方法:如铝圈法、铝管法、铝弹法、铝线法等。其中铝线法由于操作方便、设备简单、收得率稳定,已广泛在工业生产中采用。     

铝炊具中铝向食品迁移规律的探讨

铝,过去认为是人体内的一种无害的非必需微量元素。几十年来,铝炊具的应用也非常普遍。但近几年来,铝对人体的毒性引起了人们的关注。我省铝业发达,饮食、空气、环境都可影响人体铝的摄入量。本文就日常生活中使用铝具的一些实际情况,采用铝一铍试剂Ⅲ极谱技术对铝具中铝向食品中的迁移规律进行了初步探讨。     

电弧喷涂铝及铝-锌涂层在动态腐蚀介质中的耐蚀性研究

对钢铁基体表面电弧喷涂铝及铝锌涂层进行了动态腐蚀实验 ,以失质量法计算了腐蚀速度 ,并探讨了腐蚀机理。采用SEM对铝及铝锌涂层腐蚀前后的外表形貌进行了观察 ,并对铝及铝锌涂层表面进行了能谱分析 ,采用电化学系统测试了涂层的自腐蚀电位。实验结果表明 ,在 3 %NaCl水溶液中铝涂层的耐蚀性优于铝锌涂层 ;其原因是铝涂层表面上氧化膜的自愈能力及自腐蚀电位高于铝锌涂层。研究还表明 ,铝及铝锌这些阳极涂层不仅能有效地保护它所覆盖的钢铁表面 ,还能保护暴露于腐蚀介质中的钢铁基体表面。在铝、铝锌涂层上刷涂有机涂料 ,有机涂料能渗透到金属涂层的孔隙中 ,将孔隙封闭。同时 ,有机涂层和金属涂层能构成复合涂层 ,其防腐效果更佳     

电弧喷涂铝及铝—锌涂层在动态腐蚀介质中的耐蚀性研究

对钢铁基体表面电弧喷涂铝及铝-锌涂层进行了动态腐蚀实验，以失质量法计算了腐蚀速度，并探讨了腐蚀机理。采用SEM对铝及铝—锌涂层腐蚀前后的外表形貌进行了观察，并对铝及铝—锌涂层表面进行了能谱分析，采用电化学系统测试了涂层的自腐蚀电位。实验结果表明，在3％NaCl水溶液中铝涂层的耐蚀性优于铝-锌涂层；其原因是铝涂层表面上氧化膜的自愈能力及自腐蚀电位高于铝-锌涂层。研究还表明，铝及铝—锌这些阳极涂层不仅能有效地保护它所覆盖的钢铁表面，还能保护暴露于腐蚀介质中的钢铁基体表面。在铝、铝—锌涂层上刷涂有机涂料，有机涂料能渗透到金属涂层的孔隙中，将孔隙封闭。同时，有机涂层和金属涂层能构成复合涂层，其防腐效果更佳。     

隐蔽剂在螯合滴定中的应用 Ⅷ.铝矾土和硅酸盐等钛铝铁的连续螯合滴定——以苦杏仁酸和氟化物为隐蔽剂

梁树权、翁吉生曾综述硅酸盐中铁铝钛的快速分析方法。有以过氧化氢络合钛在pH3.5以过量EDTA或DCTA络合铁铝钛后用铜溶液滴定多余的EDTA而得合量,前一文献在另两份溶液中分别比色测定铁和钛,后一文献则以氟化铵隐蔽钛和铝后滴定铁并以过氧化氢法比色测定钛;铝则均以减差法求得。任继平测定高铝耐火材料的铁铝钛时是先以磺基水杨酸为指示剂在pH1.5滴定铁,继加入过氧化氢和过量EDTA以络合钛和铝后,以锌溶液回滴而得钛铝合量,最后用比色法测定钛,铝又以减差法求得。这些方法都不能在同一溶液中测定铁铝钛且铝总是以减差法求得,误差都归于铝。为了消除钛干扰铝的滴定,蒲希比等提出以三乙醇胺隐蔽铁和铝,用氢氧化钠沉淀钛,分离后在沉淀中滴定钛,滤液中滴定铁和铝。以往由于缺乏只能隐蔽钛而不隐蔽铝的试剂,使连续给合滴定铁铝钛尚     

基于萘酚醛酰腙的铝离子荧光探针

铝不是生命必需元素,过量摄入铝会引起人体机能损伤,为了警惕铝污染和预防铝的过量摄入,非常有必要开发快速、方便的铝离子检测方法。通过缩合2-羟基-1-萘醛与呋喃-2-酰肼合成了一个铝离子荧光探针(NF),具有一定的应用前景。在pH=7.0的水溶液中,NF几乎没有荧光,加入铝离子后发出明亮的青色荧光。当加入其它常见金属离子时,探针的荧光光谱几乎没有变化,而且,当它们与铝离子共存时不影响对铝离子的荧光检测,因此,探针NF对铝离子具有高选择性荧光增强响应。质谱分析研究表明二者形成了2∶1的络合物,并据此提出了NF与铝离子的可能配位结构。     

羟基铝交联蒙脱土的红外光谱研究

本文用红外光谱研究了由不同铝离子浓度、不同羟铝比的羟基铝溶液交联而成的羟基铝交联蒙脱土。结果表明,交联剂的铝离子浓度及羟铝比对交联蒙脱土的红外光谱基本无影响,而焙烧温度则有显著的影响。分析比较经不同温度焙烧后的试样的红外光谱图,得出有关羟基铝交联蒙脱土热稳定性及结构变化的信息。     

工艺因素对硼铝稀土共渗层的影响研究

本文对工具钢进行硼铝共渗,硼铝共渗工艺参数对渗层厚度、金相组织及性能的影响进行了研究。试验研究采用了正交试验分析法。结果表明,对硼铝共渗影响的主要因素是加热温度和保温时间。经硼铝共渗机理分析,稀土在硼铝共渗过程中提高了硼和铝的活性,从而使表面含硼、铝量得到提高。     

一种基于MLP神经网络的铝电解槽出铝计算方法

铝电解槽出铝量计算往往根据人工经验制定,很难建立数学模型,针对于此,对影响出铝计算的参数进行了相关性分析,筛选出电解质水平、铝水平、槽温、分子比、出铝偏差影响出铝量的主要参数,构造基于多层感知机(Multi-Layer Perception,MLP)神经网络的单槽出铝预测模型,利用经验数据完成训练,基于残差检验法检验模型的预测性能。实验结果证明了本文方法的有效性。     

大跨越架空输电导线铝部应力分布试验

为了掌握大跨越架空输电导线铝部应力空间分布特性,以JLHA1/G6A-500/280型特强钢芯铝合金导线为研究对象,采用铝股丝表面激光刻槽,内嵌高灵敏、超大复用容量超弱光纤光栅,搭建了大跨越输电导线铝部应力试验平台,研究了不同张力条件下大跨越架空输电导线铝部应力分布规律,建立了大跨越导线实体有限元模型,分析了铝股应力分布特征,并验证了试验结果的正确性。结果表明：导线承受张力作用时,外层铝股和次外层铝股应力不同,外层铝股应力小于次外层铝股应力,导线同层铝股应力基本相同;铝股应力随导线张力的增大呈线性增大趋势,张力每增大1%,铝股应力增大约10%。不同导线张力作用时钢股和铝股应力均呈现环状分层特性,铝股平均应力小于钢股平均应力,铝部和钢股应力比约为3∶7;外层和次外层铝合金股丝应力沿圆周向分布不均匀,建议大跨越导线线型设计时考虑铝股丝分层特性。     

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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