硅钼蓝光度法测定水中可溶性硅的改进

采用SnCl2作为硅钼蓝光度法中的还原剂.在使用5 mL0.15 mol/L的H2SO4酸化、室温、20min显色时间的条件下SnCl2与硅杂多酸反应生成杂多蓝,并于测试波长820nm时表现出最大吸收峰.该方法还原稳定性好,操作简便,测试灵敏度高.     

硅钼黄光度法测定油田产出水中低聚硅

建立了一种硅钼黄光度法测定三元复合驱产出水中低聚硅（单硅及一、二聚硅）的方法,研究了复杂体系三元复合驱产出水中低聚硅的定量分析．在pH值为1～2,波长在400nm处测定,硅含量在0～250mg·L^-1范围内呈良好的线性关系．此硅钼黄光度法简单易行,测定范围宽,具有一定的实用价值．     

硅钼蓝光度法测定铅锰铁中硅的含量

试样经硝酸溶解后，在0．1-0．6mol／L的酸度下，使硅酸与钼酸形成黄色硅钼酸。然后加入草硫混酸消除磷的干扰，用硫酸亚铁铵将硅钼黄还原成硅钼蓝。通过采用配制与试样相同基体的办法，加入不同含量的硅标液来测定试样中硅的含量。     

碳化硼微粉中微量硅的测定研究

本文依照硅钼蓝法原理,以抗坏血酸为还原酸,柠檬酸调节酸度还原硅钼黄,探讨碳化硼微粉中微量硅含量的测定方法,考察研究操作中各步骤的最佳工艺及其对硅含量分析精确度的影响。结果表明：本方法分析精度高且重现性好,适合于碳化硼微粉中微量硅（质量分数：0.01%～5%）的测定。     

硅钼杂多酸-聚吡咯膜修饰电极的制备及其电化学性能的研究

用电化学方法将硅钼杂多酸催化剂固定在导电聚吡咯薄膜电极上,制得了具有表面功能的硅钼杂多酸掺杂的聚吡咯薄膜修饰电极,实验发现在0．5mol/L H2SO4或0．5mol/L KCl介质中制得的硅钼杂多酸的聚吡咯薄膜修饰电极具有较好的稳定性和催化性能,用扫描电镜（SEM）,SEM－能谱仪（EDS）和X射线光电子能谱（XPS)等手段对修饰电极进行了表征。     

溶胶—凝胶法合成12—硅钼酸盐及其结构研究

本文报导了用溶胶—凝胶法自生压力下水热合成12—硅钼酸盐,并成功培养出结晶完美的大单晶体。四圆x射线衍射研究结果证明,这种12—硅钼酸盐具有Keggin结构。晶体由SiMo_(12)O_(40)~(4-)杂多阴离子及NH_4~+(C_4H_9)_2N~+H_2和H_2O分子组成,杂多阴离子SiMo_(12)O_(40)~(4-)按晶体所属空间群对称性要求,在三维空间中排列成网状结构,正离子NH_4~+,(C_4H_9)_2N~+H_2及中性水分子则处于网状结构所具有的结构孔道中,以其正电荷及氢键形成能力连接杂多阴离子网状结构,首次将二正丁胺引入杂多酸骨架,且二正丁胺以质子化的形式存在于结构中。     

Mo离子注入硅和快速退火硅化钼的形成

用大束流密度的钼金属离子注入硅，由于原子间激烈碰撞和硅片的温升而得到了性能良好的硅化钼。实验中发现，当注量均为５×１０＾１７ｃｍ＾－２时，随束流密度的增加，硅化钼生长，其电阻率明显下降，当束流密度为０．５０Ａ．ｍ＾－２时，方块电阻Ｒ口最小，其值为９０Ω。Ｘ衍射分析表明，当束流密度为０．２５Ａ．ｍ＾－２时，硅化钼衍射峰很小，难于辨认，当用０．５０Ａ．ｍ＾－２注入时，３种结构的硅化钼明显出现，对０．２     

有机锆取代的硅钼杂多酸盐及其修饰电极的电化学性质

有机锆取代的硅钼杂多酸盐 (Bu₄N)₅［(CpZr)SiMo₁₁O₃₉］ (Cp=—C₅H₅)不溶于水而溶于乙腈中, 其在酸性乙腈中显示出3步氧化还原过程, 以超微电极循环伏安法和计时库仑法与常规循环伏安法并用的办法, 探讨了它的电氧化还原过程, 各步对应2个合并的单电子转移过程; 通过吸附作用将该硅钼杂多酸盐修饰到金电极表面以制成修饰电极, 考察了其在水介质中对IO₃^-, BrO₃^-和NO₂^-的催化还原作用.     

浅谈活性硅粉：可活性硅的测定

在没有标样的情况下,试样采取盐酸介质、硝酸介质比色法进行对比,且与氟硅酸钾容量法进行对比,结果表明活性硅粉——可活性硅的测定采用钼蓝光度法进行测定结果稳定、操作简单、快速,能满足分析要求。     

合成新材料钨酸钙,钛酸钙中微量硅的测定

本文对用硅钼蓝分光光度法测定钨酸钙、钛酸钙中微量硅时,对大量干扰无素钨、钛的分离及影响硅测定的因素进行试验,确定了测定条件。方法简便、准确、重现件好。     

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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