用亚硫酸钠从分银渣中浸出银

采用稀硝酸预处理亚硫酸钠浸出体系浸取分银渣中的银,研究预处理剂硝酸和浸出剂亚硫酸钠的质量浓度、浸出固液比、温度、时间以及体系pH值对银浸出率的影响。实验结果表明:在稀硝酸质量分数为2%,亚硫酸钠质量浓度为200 g/L,pH值控制在8,固液比为1:8,反应时间为2 h,温度为30℃的条件下,银的浸出率可达95%以上。该工艺具有操作简便、能耗低及环境友好等优点,对节能环保处理分银渣具有重要意义。     

某难处理多金属矿石综合浸出铀、铜、银试验研究

针对某难浸铀矿石,采用“氯化焙烧-硫酸浸出”工艺进行处理提取铀、铜、银。研究结果表明,最佳氯化焙烧实验条件为氯化钠用量6%,氯化焙烧温度 460 ℃,氯化焙烧时间2 h,焙烧液固比0.2∶1。对氯化焙烧后的矿样进行硫酸浸出,浸出条件为:硫酸浓度30 g/L、浸出时间30 min、浸出温度70 ℃、液固比2∶1,此时金属离子铀、铜、银的浸出率分别为铀85.08%、铜95.82%、银91.80%。     

镍钼矿提钼渣中镍的浸出工艺

在硫酸溶液中,使用常压氧化浸出法处理镍钼矿提钼渣以回收有价金属镍。考察搅拌速度、液固比、硫酸用量、氧化剂用量以及浸出时间对镍浸出过程的影响。试验结果表明:搅拌速度与液固比对浸出过程影响不明显;在未加入氧化剂时,主要发生镍氢氧化物简单的酸溶反应,而添加氧化剂后硫化物也被氧化浸出;此外,镍浸出率随浸出时间、温度及硫酸用量的增加而增大。最佳工艺条件如下:搅拌速度为500 r/min,液固比为4:1,氧化剂加入量为矿量的0.2倍,浸出温度为90℃,硫酸浓度为0.4 mol/L,浸出时间为8 h,镍浸出率可达95%左右。     

钢铁厂铁鳞硫酸的浸出过程

为制备高纯氧化铁,以钢铁厂铁鳞为原料,考察液固比、温度、时间和硫酸用量对铁浸出率的影响.研究确定硫酸浸出过程的工艺条件,分析浸出过程的动力学机理.确定硫酸浸出铁鳞的最佳工艺条件为:液固比3:1,温度100℃,时间6.0 h,硫酸用量为理论量的1.25倍.在此优化工艺条件下,铁鳞中Fe的平均浸出率为91.69%.动力学研究结果表明,铁鳞的硫酸浸出过程在动力学上属收缩核模型,即满足1/2(1-a1)-2/3-1/2=Kt,受化学反应的控制,反应活化能为70.40 kJ/mol.     

不锈钢酸洗污泥中重金属的浸出试验研究

采用无机酸作为浸出剂对不锈钢酸洗污泥中的重金属进行浸出,在相同条件下,各种酸的浸出效率顺序为：硫酸 >盐酸 >硝酸.讨论了硫酸浸出酸洗污泥时浸出时间、硫酸浓度、液固比和温度等条件对金属浸出率的影响.结果表明,硫酸浓度和液固比对镍铬的浸出率有较大的影响,而温度的影响较小.在液固比为6：1、温度为30℃、硫酸浓度为3 mol/L以及浸出时间为90 min的条件下,污泥中镍、铬、铁和锰的浸出率分别为99.3%,99.2%,99.8%和93.2%,残余污泥中镍铬含量符合排放标准.     

高锰钴土矿中钴的浸提工艺

研究了高锰钴土矿中钴的浸提工艺,在酸性条件下,以SO2作还原剂,通过单因素条件试验,得到最佳浸出工艺条件.最佳浸出工艺为:二氧化硫用量为200 mL/min,温度为60℃,液固比(L/S)为4∶1,浸出时间为4 h,浓硫酸溶液的体积比为:V(浓硫酸)∶V(水)=1∶200,该条件下钴的浸出率为:96.8%.     

用废旧电路板酸浸-电沉积法回收金属铜

为了既保障环保又达到最佳铜回收效果的目的,以废旧电路板经过初步破碎分离,得到铜金属富集产品为研究对象,采用硫酸-双氧水浸出结合电沉积工艺回收物料中的铜。考察了铜浸出率与硫酸质量浓度、双氧水用量、浸出时间、液固比之间的关系,进行最佳金属浸出条件实验。结果表明：硫酸物质的量浓度为3.5 mol/L、浸出时间3 h、双氧水用量为20 mL、液固比10∶1条件下,铜金属浸出率最高可达到97.58%。电沉积尾液循环用以浸出铜,铜离子循环质量浓度不低于18 g/L,平均电流效率高于97.60%。在沉积温度40℃,阴极材料为T2紫铜,电流密度小于800 A/m2时,电流效率可以保持在97%以上。实验中铜回收率达到了97.58%。     

用AC法从高锑低银类铅阳极泥中回收银和铅

用AC法处理高锑低银类铅阳极泥,其氯化浸出渣经转化脱氯、硅氟酸浸铅、氨水浸银和水合肼还原,得到含Ag大于95%的银粉,铅以硅氟酸铅溶液返回电解精炼.在V苏打溶液/m浸出渣=4mL/g,n苏打实=1.6n苏打理,转化时间为4h及温度为80℃的最佳转化条件下,铅、银、氯的平均转化率为91.42%;在V(H2SiF6)/m浸出渣=4mL/g,浸出时间为1h,温度为50～60℃的最佳浸铅条件下,硅氟酸浸铅率为85.74%～86.07%,硝酸浸铅率大于95%;在浸银过程中,银的浸出率约为94.0%,沉银率约为98.0%.在整个工艺中,银的直收率及总回收率分别为93.63%及98.80%,铅直收率为85.91%,总回收率98.99%.     

从电解锰渣中提取金属锰

选择A,B,C,D,E等5种不同结构的浸取助剂作为研究对象,研究了固液比、浸取温度、浸取时间、酸矿比、助剂用量等因素对电解锰渣中Mn²⁺浸出率的影响.结果表明：5种助剂中E的浸出效果最好.在固液比1∶3、酸矿比0.3∶1、浸出温度60 ℃、浸出时间90 min条件下,E为助剂（用量为0.6%）时Mn²⁺浸出率最高,达到52.8%.     

二次铝灰制备α-Al_2O_3工艺

探索了以二次铝灰为原料,通过低温碱性熔炼—浸出—晶种分解制备α--Al2O3工艺.研究了碱灰比、盐灰比、熔炼温度、熔炼时间、浸出温度、浸出时间和固液比等因素对铝及硅浸出率的影响.探讨了使用晶种分解法处理浸出液制取氧化铝的工艺的可行性.结果表明:优化制备条件为碱灰比1.3,盐灰比0.7,熔炼温度500℃,熔炼时间60 min,浸出温度60℃,浸出时间30 min,固液比1∶4;铝浸出率最高可达92.71%;晶种分解法处理浸出液的后续工艺可行有效.     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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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