黑钨细泥高梯度磁选的研究

本文研究了细粒黑钨矿的高梯度磁捕集特性及其与石英的分离特性,并在此基础上对(?)岗仙钨矿黑钨细泥进行了高梯度磁选的研究。对原生钨细泥,当入选品位为0.43％(WO_3)时,获得了品位为21—24％(WO_3)的精矿,收率达73—77％;对于高锡钨细泥,当入选品位为35％(WO_3)含Sn_4％时,获得了品位为64％(WO_3),收率为90％,含Sn仅0.32％的精矿。     

90t转炉溅渣护炉水模试验研究

溅渣护炉技术是提高转炉炉龄的有效措施。通过水力学模型试验 ,探索溅渣护炉操作的最佳工艺参数。得出溅渣优化工艺参数如下 :顶枪夹角为 1 2°;顶枪枪位为 1 5 0 0～ 1 80 0mm ;顶吹气体流量大于 1 9860m3 /h;渣池初始深度为 65 0mm ;底吹气体流量为 3 1 2m3 /h。     

全面提高硬质合金质量(兰钨)

该课题的任务较多,我院承担了“兰钨相组成的定量分析方法,兰钨的制取及其氢还原的工艺基础理论研究”。具体包括下述三方面内容: 1.兰钨相组成的定量分析方法; 2.兰钨相组成与工艺参数的关系; 3.兰钨相组成对钨粉粒度的影响。 钨的兰色氧化物,简称兰钨,是钨冶金过程中的一种重要的中间产物。工业兰钨一般为多相物质的混合物。兰钨的相组成对其性质及后续产品的质量有显著影响。 制取含α-W和WO_2两相物质的标样。利用该标样,并借助于未知试样的含氧量数据,可以对含α-W、β-W和WO_2三相物质的未知试样进行X射线有标定量相分析。本研究还提供了制取铵钨青铜(ATB),ATB+W_(20)O_(58)等标样的方法。至此,可以对兰钨中的各相进行X射线有标定量相分析。     

关于转炉溅渣护炉技术的工艺参数优化探讨

溅渣护炉是转炉护炉技术的重大进步,这项技术能够大幅度提高转炉炉龄、降低耐火材料消耗,在我国有着了广阔的广应用前景。从转炉溅渣护炉的机理入手,介绍了溅渣护炉的工艺特点,探讨了炉渣成分的优化研究,分析了溅渣操作中枪位、时间等的控制,对溅渣护炉的工艺参数进行优化,以期更好地运用溅渣护炉技术。     

镍转炉溅渣护炉热态模拟

为将溅渣护炉技术应用于炼镍转炉,在实验室镁铬质坩埚中进行了热态模拟溅渣实验.结果表明:FeO-Fe2O3-SiO2-MgO渣系为镍转炉溅渣护炉的合理渣型,增加渣中MgO和Fe2O3含量可以明显提高炉渣熔化温度,相应渣中高熔点相铁镁橄榄石和磁铁矿显著增加,采用此类炉渣溅渣可在镁铬砖内壁形成高熔点的溅渣层;溅渣后坩埚内壁的溅渣层由反应层和挂渣层组成,其中反应层物相为镁铁固溶体和镁铬铁铝尖晶石,挂渣层主要由铁镁橄榄石和磁铁矿组成.溅渣时采用空气喷吹可增加渣中Fe2O3,适合作为溅渣气源.     

钨渣中有价金属综合回收工艺

对从钨渣中回收钽、铌的工艺进行了研究;采用苏打焙烧水浸与酸浸结合的湿法处理,经实验确定了最佳工艺条件:苏打用量为理论量的6.0倍,焙烧温度为850～950℃,焙烧时间为50 min.水浸液固比为6:1,时间为90 min;酸煮时HCl浓度为20％,浸出液固比为6:1,时间为60min.按照以上条件处理钨渣,可获得含Ta2O5+Nb2O5达15.89％(其中w(Ta2O5)为4.06%)的钽铌富集渣,钽铌回收率达79.46%.该工艺既可完善我国现行的钨冶金流程,充分利用自然资源,获得可直接应用的钽铌生产原料.又可减少大量钨渣堆存引起的环境污染问题.     

100t转炉溅渣护炉工艺研究

为某厂100 t顶吹转炉溅渣护炉提供最佳工艺参数,按照转炉相应比例设计水力模型并试验研究。根据试验结果,优化溅渣护炉工艺参数,相应调整溅渣氮气压力和枪位,提高了溅渣效果,溅渣后炉渣均匀涂覆到炉衬上,溅渣时间缩短到2.5~3 min,进一步提高了转炉炉龄,实现24 025炉的新记录。     

100t转炉溅渣护炉工艺研究

为某厂100 t顶吹转炉溅渣护炉提供最佳工艺参数,按照转炉相应比例设计水力模型并试验研究.根据试验结果,优化溅渣护炉工艺参数,相应调整溅渣氮气压力和抢位,提高了溅渣效果,溅渣后炉渣均匀涂覆到炉衬上,溅渣时间缩短到2.5～3 min,进一步提高了转炉炉龄,实现24025炉的新记录.     

转炉溅渣护炉工艺

介绍了转炉溅渣护炉工艺，并对影响溅渣护炉工艺的几个关键因素及其注意事项作了阐述。     

白钨精矿与黑白钨混合矿碱分解方法及设备

本发明采用碱分解钨矿物以提取钨,特点是:1.对原料的适应性广,能分解含WO~310—74％的各种钨矿原料,包括白钨精矿,黑钨精矿,低WO~3品位高杂质的黑白钨混合中矿(含钨细泥);2.流程短,能耗低,不需单独磨矿,碱用量低,无须回收过量NaOH,比国内外现工艺少1—3个工序;3.钨回收率高2—3％,当选冶结合直接分解重、浮粗选所得黑白钨     

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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