金属离子对牛胰岛素淀粉样纤维形成的作用

采用硫黄素（Thioflavin T,ThT）和8-苯氨基-1-萘磺酸（8-Anilinonaphthalene-1-sulfonic acid,ANS）荧光、圆二色谱和偏振光显微镜等方法研究了溶液中金属离子(Mg2+, Cu2+, Zn2+, Co2+, K+, Li+ 和 La3+) 对牛胰岛素淀粉样纤维形成的影响,结果表明,所有金属离子对胰岛素淀粉样纤维化均有促进作用,其作用大小次序为：La3+＞Mg2+＞Cu2+＞Zn2+＞Li+＞Co2+＞K+.这种作用与促进蛋白质疏水区暴露的作用是一致的.相关     

La_(0.5)Eu_(0.2)Sr_(0.3)MnO_3钙钛矿型锰氧化物的~(151)Eu穆斯堡尔效应

利用穆斯堡尔效应研究了A位La被Eu替代的锰氧化物La0.5Eu0.2Sr0.3MnO3和La0.4Eu0.3Sr0.3MnO3的磁性、导电性、磁电阻效应.一定比例的Eu掺杂能够使La0.7Sr0.3MnO3样品出现M-I转变.穆斯堡尔参数表明在250 K附近存在一种磁结构转变;高温区T＞260 K时,θD=120 K,低温区T＜360 K时,θD=260 K.     

稀土金属离子对梨形四膜虫(Tetrahymena pyriformis)的生长毒性

采用S1上海梨形四膜虫（Tetrahymenapyriformis）进行金属离子La3+.Sm3+.Y3+.Gd3+的24h和96h生长毒性试验．结果表明La3+,Sm3+．Y3+在低剂量下均表现出对四膜虫的刺激效应．但在高剂量时上述四种稀土金属离子都表现出抑制效应．而且随着浓度的升高．抑制作用增强．其毒性大小顺序为Gd3+＞Y3+＞Sm3+＞La3+,并且重稀土的毒性要高于中稀土．轻稀土的毒性．     

LCMO,LSMO单、双层薄膜的制备和电学性质

采用脉冲激光沉积法在Si衬底上沉积La1-xCaxMnO3,La1-xSrxMnO3(x=0.2,0.5,0.8)单钙钛矿锰氧化物单层膜和双层膜.采用LCR仪等分析测试手段研究了薄膜异质结的电流-电压特性.I-V特性曲线表明:单钙钛矿La1-xCaxMnO3/Si和La1-xSrxMnO3/Si均表现出了与传统p-n结相似的整流特性,但是La1-xCaxMnO3/Si的整流特性要明显优于La1-xSrxMnO3/Si,这可能是因为La1-xCaxMnO3同衬底晶格常数更为匹配且Sr掺杂引起的晶格畸变场势阱更深的缘故.在双层膜结构中可能是由于能带结构的原因,按La1-xSrxMnO3/La1-xCaxMnO3/Si顺序排列的异质结相当于p+-p-n结构,I-V特性明显类似传统的整流特性,而La1-xCaxMnO3/La1-xSrxMnO3/Si顺序的异质结相当于n-p-n型,整流特性不明显.     

稀土在农作物中吸收分布

通过对农作物中5个稀土元素(La、Ce、Nd、Y、Gd)的含量分布以及单一稀土的分布规律的研究.结果表明: 农作物吸收稀土的能力与土壤可给稀土量呈正相关,植物体各部位稀土含量分布一般为根＞叶＞茎＞果实;单一稀土在根部的分布特征是La＞Ce＞Nd＞Y＞Gd,在叶,茎,果实的分布特征是Ce＞La＞Nd＞Y＞Gd,说明轻稀土较重稀土易被植物吸收;植物在生长不同期吸收稀土的能力大小为:幼苗期＞分枝期＞成熟期.总之,稀土元素在植物中不易迁移,主要集中在根部,果实中含量甚微.     

固相反应合成La_(1-x)Sr_xMnO_3的机理

以La2O3,MnO2和SrCO3为原料,通过固相反应合成SOFC的阴极粉料LSM,利用XRD,TGA/DTA热分析仪等现代分析仪器研究了该材料的反应历程.结果发现,实验过程首先出现了La2SrOx相,并在350～1000℃的较大范围内一直存在,到800℃时才出现LaMnO3.通过分析研究,反应过程先是La2O3+SrCO3→La2SrOx+Co2,然后为La2O3+MnO2→LaMnO3,,最后发生La2SrOx和LaMnO3向La1-xSrxMnO3转化.这一结果与人们一致公认的反应历程,即先发生La2O3+MnO2→LaMnO3,然后是LaMnO3+SrCO3→La1-xSrxMnO3有较大差异.     

固相反应合成的机理La1-xSrxMnO3

以La2O3, MnO2和SrCO3为原料,通过固相反应合成SOFC的阴极粉料LSM,利用XRD,TGA/DTA热分析仪等现代分析仪器研究了该材料的反应历程.结果发现,实验过程首先出现了La2SrO相,并在350~1 000℃的较大范围内一直存在,到800℃时才出现LaMnO3.通过分析研究,反应过程先是La2O3+SrCO3→La2SrO+CO2,然后为La2O3+MnO2→LaMnO3,,最后发生La2SrO和LaMnO3向La1-xSrxMnO3转化.这一结果与人们一致公认的反应历程,即先发生La2O3+MnO2→LaMnO3 ,然后是LaMnO3+SrCO3→La1-xSrxMnO3有较大差异.     

络合溶胶-凝胶法制备La_(1-x)Zn_xCoO_3纳米晶及其对酸性黑10B的光催化降解

以柠檬酸为络合剂,采用络合溶胶-凝胶法合成La1-xZnxCoO3系列稀土复合氧化物纳米晶.通过TG-DTA,XRD,SEM等手段对凝胶的热分解机理,La1-xZnxCoO3的形成过程,纳米晶的物相结构,微观形貌,粒度大小等进行了研究.结果表明,前驱物在600℃焙烧时即可得到颗粒细小、组分均匀、钙钛矿型的La1-xZnxCoO3纳米晶.颗粒基本呈球形,粒径约为50nm,分散性较好.与传统的固相反应相比,用该法制得的La1-xZnxCoO3组分均匀,化学剂量比易于控制,烧成温度低.光催化性质研究发现,在适宜条件下La1-xZnxCoO3纳米晶可使染料酸性黑10B的脱色率达91.33%.     

稀土掺杂TiO2薄膜的制备及光催化特性

用Sol-gel法制备出一系列镧系离子掺杂的TiO2薄膜,经X射线衍射(XRD)、紫外可见(UV-Vis)吸收光谱表征该TiO2薄膜,并研究了其光催化活性. XRD研究结果表明:镧系离子掺杂TiO2薄膜的XRD与未掺杂薄膜的XRD基本一致. 在控制实验条件下,主要为锐钛矿型晶型. UV-Vis吸收光谱表明:当λ＞360 nm时其吸光值低于0.4,并测得薄膜的厚度.光催化降解罗丹明B的实验表明,掺杂稀土离子的TiO2薄膜的光降解效率高于未掺杂的TiO2薄膜. 当n(La)=0.5%,n(Eu)=0.7% ,n(Er)=0.8% (n为摩尔比)时的降解效率达到最大. 而不同镧系离子在最佳掺杂量时的光降解效果为:La3+＞Eu3+＞Er3+.     

羰基铁/La1-xSrxMnO3（x=0.3,0.4）复合物的制备及微波吸收性质研究

用溶胶凝胶法合成了La1-xSrxMnO3(x=0.3,0.4)纳米颗粒,并用物理混合的方法合成了不同重量比例的羰基铁/La1-xSrxMnO3复合物样本,研究了复合物的结构,形貌及微波吸收性质.研究结果表明:复合物中羰基铁与La1-xSrxMnO3颗粒的比例显著地影响着复合物的吸波性质.当复合物中羰基铁与La0.6Sr0.4MnO3颗粒的重量比达到30∶1时,复合物的吸波性能达到最佳值,这可能归功于复合物的介电性能和磁性能在此种状态下达到匹配平衡.     

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     

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