基于冲天炉熔炼条件脱硫工艺的研究

在冲天炉熔炼过程中,为了获得低硫铁液,通常采用脱硫工艺措施。通过比较研究：炉内脱硫主要用于碱性炉衬的冲天炉,通过强化底焦燃烧的措施,提高炉温以及降低焦炭用量,提高炉渣的碱度,防止铁液的氧化等,都将减少铁液含硫量;而炉外脱硫用于酸性炉衬的冲天炉。混合脱硫剂炉外脱硫时,出铁温度、焦炭用量、熔化率、铁液中含硫量等技术指标明显高于单一脱硫荆。通过对冲天炉熔炼条件下的炉内与炉外脱硫工艺的研究,为铸造车间生产提供科学依据。     

铸造焦对提高合金铸铁件质量的作用

冲天炉是熔炼铸铁件的主要设备。当愈来愈多性能优良的合金铸铁从实验室走向生产应用的时候，人们关注到铁水的熔炼质量是关系成果转化的成败关键。从合金铸铁件生产工艺对熔炼质量提出的要求出发，以焦炭燃烧模型、链式反应为切入点［１］，提出：只有大力推广铸造焦的使用，才能加速实验室成果向生产应用的转化速率，才能得到生产条件下的优质合金铸铁件。     

热风条件下除湿送风的熔炼试验研究

在３００℃左右较高热风温度下对冲天炉熔炼的空气进行除湿送风，可进一步强化焦炭燃烧和传热过程，降低炉内的氧化性。试验表明，铁水温度提高１５～２５℃，熔化率提高１０％左右，炉渣氧化铁、合金元素烧损及焦耗进一步降低，为同时采用两种强化措施提供了依据。     

热风条件下除湿送风的熔炼试验研究

在３００℃左右较高热风温度下对冲天炉熔炼的空气进行除湿送风，可进一步强化焦炭燃烧和传热过程，降低炉内的氧化性。试验表明，铁水温度提高１５－２５℃，熔化率提高１０％左右，炉渣氧化铁，合金元素烧损及焦耗进一步降低，为同时采用两种强化措施提供了依据。     

铸造焦反应能力的研究

本文通过对冲天炉热交换过程的分析后指出,焦炭在炉内的作用不仅是作为燃料,更重要的是在铁水过热时所起的传热介质作用,尤其影响铁水过热效率的关键因素是冲天炉过热区内的焦炭表面燃烧温度。文中在进一步分析了冲天炉内燃烧特点后认为,确定反应能力是铸造焦的重要技术指标的依据是它直接影响了铁水的过热效率。文中最后指出,必须依据冲天炉实际工况制定出铸造焦反应能力的测试方法。     

冲天炉熔炼过程中终硫量的估算

本文给出了在一定生产条件下用冲天炉熔炼铸铁时估算铁水中终硫量的方法,并在生产中将估算值与实测值进行了比较,证明冲天炉熔炼铸铁过程中铁水的终硫量是可以较为准确地估算的,这对控制铸铁件质量具有重要意义。     

冲天炉熔炼过程参数变化及其检测方法

本文主要讨论了双排大间距冲天炉熔炼过程的特点及参数的变化特征,研究了各参数的检测方法,各参数的变化对冲天炉炉况的影响,以及如何根据参数的变化对冲天炉实施控制。根据冲天炉熔炼过程的特点选择检测参数,根据检测参数的变化判断冲天炉的熔炼情况和异常情况的产生,由此指导冲天炉的熔炼过程,提高了冲天炉的出炉铁水温度。     

冲天炉过热区热交换机理新探

本文通过模拟研究,得出了冲天炉过热区内对铁水的四种传热方式的传热系数。四种传热方式中,焦炭对铁水的接触传热与辐射传热共占85％左右,焦炭表面燃烧温度的高低对热交换有决定性的影响。焦炭表面温度与炉气温度有较大差别,它主要受焦炭性能影响,是衡量铸造用焦炭质量的一项不可替代的综合性指标。     

生物质燃烧特性与动力学分析

为丰富农林业生物质利用方式,通过热重分析法研究生物质在不同条件下的燃烧特性及其动力学特性。研究表明,不同生物质燃烧特性明显不同。稻壳经不同温度水洗后综合燃烧特性指数增加,最大燃烧速率提高6.0~7.6 %/min,燃烧活化能高于原样,且在一定范围内水洗温度越高,焦炭燃烧阶段活化能越小;提高升温速率,生物质的着火温度、燃尽温度、残余率、最大燃烧速率及综合燃烧特性指数提高;生物质的燃烧反应遵循一级反应动力学模型,相关系数达0.955以上,挥发分析出燃烧阶段活化能均大于焦炭燃烧阶段。该实验结果可为生物质在火力发电行业应用提供参考。     

焦炭固定床燃烧氮氧化物排放实验研究

为降低锅炉NO的排放,研究焦炭在固定床中燃烧时的氮氧化物排放特性,分析焦炭数量对NO排放的影响。在其他条件不变的情况下,取焦炭质量分别为0．5、1．0和2．0g的煤样进行燃烧实验。结果表明：焦炭燃烧NOx排放与燃烧过程密切相关,在固定床中有还原层存在时,NO排放处于低水平稳定状态。随着焦炭还原层的消失,NO转化率迅速增加。在设计层燃燃烧锅炉时。加大燃煤炉中焦炭层的厚度．可以降低锅炉NO的排放．焦炭层厚度增加4倍．NOx排放降低73．86％．     

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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