纳米粒子浓度等条件对VS55反玻璃化结晶的影响

借助低温显微镜系统,运用等温扫描和连续扫描法,对磁性纳米粒子浓度、等温温度以及降复温速率对低温保护剂VS55在反玻璃化过程中的结晶行为进行了观察.结果显示:随着磁性纳米粒子浓度和等温温度的增加,冰晶生长速率、初始尺寸及结晶密度整体上都增大,冰晶生长得到促进;对含有不同磁性纳米粒子浓度的VS55进行连续扫描,结果与等温扫描结论一致,添加磁性纳米粒子的溶液反玻璃化冰晶生长明显;降温速率增长至5℃/min时,冰晶初始尺寸和冰晶数量显著提高,生长速率也略有增加,5℃/min以上的降温速率对冰晶的影响差别不大;随着复温速率的增大,冰晶尺寸、生长速率都减小,冰晶数量减少.     

温轧态Al-Sc二元合金的再结晶

研究了一种温轧态 Al-Sc 二元合金的再结晶温度、ScAl_3 相对合金再结晶的影响以及再结晶的形核机制。结果表明:温轧态 Al-Sc 二元合金的再结晶起始温度为 350℃,终了温度为510℃;细小,弥散的ScAl_3对位错的钉扎作用是合金再结晶温度高的原因;再结晶过程为亚晶聚合及亚晶长大形核机制的双重作用。     

7075铝合金液相线铸造过程中的形核

研究了7075铝合金在液相线及液相线温度附近等温形核过程和组织变化情况·在液相线温度以上(645℃),熔体激冷形核数量相对较少,晶粒较大,单位面积晶粒数较少且基本不随保温时间变化;在逼近液相线温度(632℃),熔体大量形核,晶粒细小球化,单位面积晶粒数较多,随保温时间先增加后减少,在30min左右达到最大值;在液相线温度以下(615℃),熔体形核数量多,但部分合并长大,细小的晶粒中伴随着一些粗大晶粒,单位面积晶粒数较少,随保温时间先增加后减少,在30min左右达到最大值·结果表明,在逼近液相线温度(632℃)下形核保温30m...     

复温速度对红元帅苹果品质影响研究

为了研究不同复温速度(1.5℃/min和4.5℃/min)冷冻处理的红元帅苹果其理化品质的影响,通过测定Vc含量以及亮度和硬度发现,复温速度会明显影响红元帅苹果的Vc含量以及亮度和硬度.复温速度越高,Vc含量以及亮度和硬度下降的速度会有所缓解.同时,在不同复温速度处理条件下,测定a*、b*和可滴定酸含量,复温速度更高,...     

亚高山红桦根及根际土壤生化特性对升高温度和CO2的响应

通过川西亚高山野外大型控制实验,研究了红桦不同密度下的根系生物量、根际土壤微生物数量和根际土壤酶活性对短期升高温度（ET,相对室外平均升温2.4±0.4 ℃）、升高大气CO2浓度（EC,平均增加15.5±1.0 μmol·L^-1）及交互作用（ETC,生长室相对室外平均升温2.2±0.5　℃并CO₂浓度平均增加15.8±1.2　μmol·L^-1）的响应.初步结果表明：升高大气温度或CO₂浓度均能够显著促进红桦低密度和高密度下单株根系生物量;升高温度和CO₂浓度及二者共同升高对微生物类群和数量影响不同,升高温度细菌、真菌数量以及低密度下放线菌数量显著增加,而高密度下放线菌数量显著下降;升高CO₂浓度下高密度时细菌和真菌数量增加而低密度下均显著下降;升高温度（ET）显著抑制高、低密度下红桦根际土壤多酚氧化酶活性,升高CO₂（EC）根际土壤过氧化氢酶活性在2种密度条件下均不同程度升高,土壤脲酶和多酚氧化酶活性则降低;ETC条件下,根际土壤多酚氧化酶和过氧化氢酶在2种密度下均表现出不同程度的降低,但脲酶活性在高、低密度条件下对ETC表现出不同的响应结果.     

温轧态Al-Sc二元合金的再结晶

研究了一种温轧态Al—Sc二元合金的再结晶温度、ScAl_3相对合金再结晶的影响以及再结晶的形核机制。结果表明:温轧态Al—Sc二元合金的再结晶起始温度为350℃,终了温度为510℃;细小、弥散的SeAl_3对位错的钉扎作用是合金再结晶温度高的原因;再结晶过程为亚晶聚合及亚晶长大形核机制的双重作用。     

海洋温差能发电系统新型热力循环理论分析

 海洋温差能发电系统新型热力循环在Kalina循环基础上增加贫氨溶液回热支路和抽气回热支路以提高热力循环效率。应用能量守恒原理和热平衡方程对新型热力循环--国海循环进行理论研究,计算了不同的透平入口蒸汽压力、氨水混合工质浓度、温海水温度和冷海水温度条件下的循环效率。理论计算结果表明,氨水混合工质浓度对国海循环效率影响显著,冷热源温度确定的条件下存在最优的氨水混合工质浓度使得循环效率最高,当温、冷海水温度分别为26、5℃,氨水工质浓度为92%时,系统效率最大达到4.56%;当氨水混合物浓度不变时,循环效率随透平入口蒸汽压力的升高先升高后降低,存在极大值;冷海水入口温度对循环效率影响很明显,而温海水温度对循环效率影响较小。     

自复叠制冷循环双温冰箱设计的理论研究

为了给冰箱提供不同的闻室温度来满足储存要求,将采用非共沸混合制冷剂的自复叠制冷循环应用于双温冰箱系统,研究了两间室蒸发器出口温度、冷凝器出口温度、冷藏室与冷冻室制冷量比例及冷凝蒸发器高压侧出口过冷度的变化对冰箱系统优化设计的影响.结果表明:系统性能系数随着冷藏室和冷冻室蒸发器出口温度的降低、冷凝器出口温度的升高而减小;提高两间室制冷量的比例可增大性能系数,但压缩机耗功和压力比也同时增大;增大冷凝蒸发器高压端出口侧制冷剂的过冷度可以减小压缩机耗功,提高系统性能系数.研究结果对于自复叠双温冰箱的实际推广提供了参考.     

动物体的人工降温及复苏

用蟾蜍及大白鼠进行人工降温达到低体温，用不同方式复温，以表现二者体温变化，曲线及致死低温界限不同，若保护大白鼠心区及脑部再降低体温，则致麻醉温度相应降低；当先复温心区，脑部，则复苏率提高。     

达旦黄与牛血清白蛋白作用的光谱特性

以达旦黄为探针,应用荧光及紫外光谱法研究达旦黄(TY)与牛血清白蛋白(BSA)分子间的结合反应,测定了不同温度下的结合常数和结合位点数.实验表明:TY对BSA内源荧光的猝灭机理为静态猝灭,作用力类型为疏水作用.根据Frster能量转移理论,求得不同温度(16 ,30 ,40 ℃)下的能量转移效率E分别为0.419 6,0.401 9,0.386 5,作用距离r分别为3.05,3.04,3.10 nm.BSA存在猝灭TY的荧光,以此为基础建立了测定BSA的方法,线性范围:3×10-7～2×10-5 mol/L,检出限:9.07×10-7 mol/L,相对标准偏差:RSD=1.7%.     

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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