异型DEFC管状阴极传质过程的模拟研究

以中间相碳微球（MCMB）、石墨粉为原料用凝胶注模成型工艺制成阴极管烧结体,并在烧结体外涂覆扩散层、Pt／C催化层和Nation膜制备管状阴极．利用CFD软件对直接乙醇燃料电池（DEFC）管状阴极的传质过程进行模拟计算和研究,在不同的工作温度、阴极扩散层孔隙率、进气压力以及阴极催化层厚度的条件下,分析DEFC阴极催化层表面的液态饱和度、氧气的摩尔质量分数的变化情况．结果表明：增大阴极扩散层孔隙率、进气压力、催化层厚度和电池温度有利于阴极的传质过程．     

低压粉末注射成型FeCrAl合金成型性能的研究

采用低压粉末注射成型技术制备FeCrAl多孔材料,并研究了粘结剂配比和温度对其成型特性的影响。将FeCrAl合金粉末与不同配方的粘结剂混合,分别采用差示扫描量热仪（differential scanning calorimetry, DSC）、热重分析仪（thermogravimetric analyzer, TGA）和旋转流变仪测试混合物的熔化温度、分解温度以及不同转速和温度下的黏度,计算原料体系的塑性成型指数。结果表明,不同粘结剂配比和不同温度下,原料的流变行为和成型特性不同。成型温度越高,黏度越低,成型性越好。相同温度下,石蜡和石蜡/硬脂酸配方成型性较好,但原料在高转速下易分层,且压注样品在溶液脱脂过程中发生溃散;采用石蜡/低密度聚乙烯/硬脂酸和石蜡/乙酸乙烯共聚物/硬脂酸配方制备的样品,成型性较好,且高转速下原料稳定。采用石蜡/低密度聚乙烯/硬脂酸配方制备的样品,经脱脂烧结后,外观完好,粉末之间呈现冶金结合,维氏硬度为210,抗弯强度为（250±20）MPa。     

低密度高强度炭材料的制备研究

以活化石油焦粉为原料,煤沥青为粘结剂,在不同成型压力和保压时间下制备的生坯样品并焙烧,成功制得高强度炭材料.对样品进行力学性能检测以及SEM,TGDTA,XRD分析,并阐明了活化原料与粘结剂相互作用机理.试验结果表明,随着保压时间和成型压力的增加,生坯体密及焙烧品性能都有所提升.在保压时间为20min,成型压力为200MPa时,焙烧后样品体积密度为1.54g/cm~3,抗压强度119 MPa,抗折强度61 MPa,各项性能均优于未活化石油焦粉原料所制样品.     

热压成型制备玉米芯基生态炭

以来源丰富、价格低廉的玉米芯为原料,通过炭化和活化（水蒸气为活化剂）制备生态炭.为提高生态炭的收率,炭化前采用热压成型的方法对玉米芯原料进行预处理.通过对成型温度、成型压力、成型时间等工艺参数的研究,得出较佳热压成型条件:成型温度为275～300℃,成型压力为5～15MPa,成型时间为10 min.研究结果表明,成型工艺参数对总炭化收率的影响程度由大到小依次为:成型温度＞成型压力≈成型时间;热压成型使玉米芯的炭化收率由成型前的18.52％(质量分数)提高到成型后的25.58％;热压成型对生态炭的比表面积影响较小,所制生态炭比表面积为982m2/g,以微孔为主,微孔率高达97.31％.     

制备方法对石墨粉结构及嵌锂性能的影响

由不同制备方法获得3种石墨粉，对它们进行了结构分析和电化学嵌锂性能的研究.通过XRD、SEM和BET比表面积等结构测试，发现以某种方式粉碎石墨化成型体可以获得石墨化度高、微晶尺寸小、颗粒内有大量微裂缝的石墨粉.这种石墨粉具有高比容量和良好的循环性能.组装成扣式电池以0.32mA/cm     

细粒石墨材料的热压制备

以细粒石墨粉为原料、改质和高温煤沥青为黏结剂,采用热压成型工艺制备炭块,并对其进行炭化和石墨化处理后得到石墨块体.结果表明,随着热处理温度的上升,热压制备炭块的体积密度和电阻率发生了明显的变化,与改质沥青相比,以高残炭率沥青为黏结剂所制细粒石墨材料具有较高的体积密度和较低的电阻率;X射线衍射XRD和扫描电镜SEM分析表明,细粒石墨在块体材料中具有明显的取向性.     

细粒石墨材料的热压制备

以细粒石墨粉为原料、改质和高温煤沥青为黏结剂,采用热压成型工艺制备炭块,并对其进行炭化和石墨化处理后得到石墨块体。结果表明,随着热处理温度的上升,热压制备炭块的体积密度和电阻率发生了明显的变化,与改质沥青相比,以高残炭率沥青为黏结剂所制细粒石墨材料具有较高的体积密度和较低的电阻率;X射线衍射XRD和扫描电镜SEM分析表明,细粒石墨在块体材料中具有明显的取向性。     

成型压力对废弃物基地质聚合物制品性能的影响

采用压制成型法,利用工业固体废渣为原料,制备了一类能耗低、免烧的地质聚合物.研究了压制成型时成型压力对制品强度、体积密度、吸水率、软化系数、耐磨性、耐水性以及抗冻融循环的影响,并结合SEM及XRD分析试样的微观形貌和矿物组成.试验结果表明:成型压力对地质聚合物制品的性能有重要影响,制备该废弃物基地质聚合物制品的最佳成型压力为30 MPa.     

Fe/Al2O3/Fe隧道结的巨磁电阻效应

采用多靶离子束溅射镀膜技术制备了Ｆｅ（２００℃退火）／Ａｌ２Ｏ３／Ｆｅ多隧道样品,研究了隧道结样品的巨磁电阻效应,在室温下获得了５．８９％的巨磁电阻效应,具有甚高场灵敏度并且测量了样品的伏安特性曲线,观察到了非线性的伏安特性曲线,证明了隧道效应的存在。     

高压成型（PrNd）_xAl_（0.7）Nb_（0.6）Cu_（0.1）B_（1.05）Fe_（97.55-x）合金的超精细结构分析

采用高压和常压方式制备出（PrNd）xAl0.7Nb0.6Cu0.1B1.05Fe97.55-x（质量百分比）合金,由扫描电子显微镜、振动样品磁强计、穆斯堡尔谱仪和电子自旋共振谱仪对比研究了两种压制方式对样品微观结构、磁性能和超精细结构的影响.结果发现：与常规压制方式制备的样品相比,采用1.8GPa成型得到的样品Hcj（内禀矫顽力）和（BH）max（最大磁能积）分别提高了133kAm-1和0.6kJm-3;而采用3.6GPa成型样品的Hcj和（BH）max分别提高了120.3kAm-1和3.2kJm-3.高压成型样品的R-rich相、富B相和α-Fe相较少,围绕铁原子的其他原子固有的对称性被改变,g因子增大.0.2,1.8和3.6GPa成型得到样品的内磁场Hin分别为2.206×104,2.205×104和2.194×104kA/m.     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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     

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