干银鱼贮藏过程中色泽变化动力学研究

在4种不同温度(0℃、10℃、20℃、30℃)下贮藏干银鱼,利用色差计测定了干银鱼的色泽明度值,并分析了色泽变化的动力学模型.研究发现:随着时间的延长,干银鱼明度值逐渐下降,而且温度越高,下降越快;温度在10℃以内,明度值随时间变化缓慢,温度越低变化越缓慢,温度高于20℃时,明度变化较快;干银鱼色泽明度值随时间的变化适合一级化学反应动力学模型,速率常数采用阿伦尼乌斯方程,其化学反应活化能为55.654 kJ/mol.     

鲜切马铃薯贮藏期间微生物生长模型的建立

研究鲜切马铃薯经保鲜处理后在0℃和15℃贮藏温度下细菌生长趋势和感官质量的变化,建立微生物生长模型.结果表明:以不同温度下贮藏鲜切马铃薯菌落总数测定结果建立的微生物生长模型为:y=4.2543exp[-exp(1.4029-0.2765d)](0℃)和y=4.1749exp[-exp(0.7888-0.3929d)](15℃),验证试验表明建立的Gompertz模型能有效地拟合不同贮藏温度和时间条件下鲜切马铃薯菌落总数的动态变化,有效地评估鲜切马铃薯的货架寿命和贮藏安全性.试验同时探讨了细菌菌落和鲜切马铃薯组织褐变的关系,结果显示当菌落总数≤105CFU/g,鲜切马铃薯不会出现显著地褐变和腐败现象.     

EGSB反应器中特殊功能颗粒污泥单组分甲烷化动力学的研究

对从已经完成厌氧甲烷化反硝化与厌氧氨氧化耦合的EGSB反应器中取出的功能颗粒污泥进行厌氧甲烷化动力学试验研究,建立厌氧甲烷化反应动力学方程。试验结果表明:甲烷化比基质降解速率基质浓度的关系遵从Monod方程。对甲烷化进行动力学分析,求出其动力学参数:最大比基质降解速率Vmax=0.158h-1,半饱和常数Ks=464.27mg/L,甲烷的产率系数y=0.254ml/mg。     

刚体地球极移和章动的联合动力学方程

以经典的刚体地球自转欧拉动力学理论为基础,通过引入章动坐标系相对惯性空间的运动,推导出了一个同时包含极移和章动的刚体地球自转联合动力学方程。在推导过程中首次考虑了高阶岁差章动力矩(摄动周期满足2d/3相似文献   

蟹糊贮藏过程品质变化的动力学模型研究

研究蟹糊在不同温度下储藏过程中菌落总数和挥发性盐基氮的变化规律,并建立动力学模型,为预测蟹糊在流通领域中品质变化提供参考。结果表明:蟹糊的菌落总数和挥发性盐基氮值随着贮藏时间延长而增加,随着贮藏温度增高而上升;建立的菌落总数和挥发性盐基氮随时间和温度变化的回归方程,验证得出的方程回归系数均>0.9,具有较高的拟和精度。建立的动力学方程中微生物生长活化能(En)为112.4KJ/mol、微生物生长速率常数(kn)为1.049×1020e-112413.6/RT;挥发性盐基氮活化能(Et)为119.1kJ/mol、挥发性盐基氮速率常数(kt)6.1×1020e-119106.3/RT,经验证在温度0～25℃内,所建数学模型能较好地反映蟹糊贮藏期间的品质变化的过程。     

弹性地球极移和章动的联合动力学方程

基于经典的弹性地球自转动力学理论，通过引入章动坐标系相对惯性空间的运动，推导出一个同时包含极移和章动的弹性地球自转联合动力学方程。在推导过程中首次考虑了高阶岁差章动力矩和其它摄动因素(摄动周期满足0．5d≤T≤1．5d)对地球自转的影响，从而使得方程更加完备和完美，与现行的地球自转动力学方程相比较表明，该方法综合性强而且易于理解。     

环面上Van der Pol方程的研究

本文对环面上Van der Pol方程 dx/dt=sin y,dy/dt=-sinx μsin 3y(x mod 2π,y mod 2π)的极限环问题进行研究,得到下述两个结果定理1 环面上Van der Pol方程对于μ=0,μ≤-1和μ≥1不存在第一类极限环。定理2 环面上Van der Pol方程对于非零的小参数μ至少存在两个第一类极限环。     

液核地球极移和章动的联合动力学方程

以经典的液核地球自转动力学理论为基础,通过引入章动坐标系相对惯性空间的运动,建立了液核地球极移和章动的联合动力学方程。主要内容有：（1）顾及了高阶岁差章动力矩对地球自转的影响;（2）引入了摄动周期满足T≤2/3d和T≥2d的其他因素（大气、海洋和地表水分布变化等）对地球自转的影响;（3）建立了自转轴极移和任一天球参考轴极移和章动之间的理论关系;（4）建立了液核地球极移和章动的联合动力学方程,试图用统一的方法研究极移和章动。作者给出的理论公式可为动力大地测量学和天文地球动力学的研究提供理论参考和依据。     

铵光卤石过饱和溶液低温结晶动力学研究

研究了10℃、20℃铵光卤石过饱和溶液的结晶动力学规律.利用10℃、20℃的溶解度和动力学参数建立了铵光卤石结晶动力学方程.10℃、20℃结晶的动力学方程分别-dc/dt dc=0.045(3.276-c)~(4/3)(c-2.457),-dc/dt=0.028(4.736-c)~(4/3)(c-3.552),动力学方程证明铵光卤石的低温结晶受单核结晶生长控制.     

无水醋酸锌与无水草酸固相反应动力学的研究

用等温热重法研究了无水醋酸锌与无水草酸的固相化学反应,反应分2步进行,通过对转化率数据α进行动力学拟合得到了反应的动力学方程.转化率α较低时发生第一步反应,动力学方程(1－α)－1/2=Ae－E/RTt式中E=70.72kJ/mol、A=4.43×108min－1;转化率α较高时发生第二步反应,动力学方程(1－2α/3)－(1－α)2/3=Ae－E/RTt式中E=122.7kJ/mol、A=9.81×1014min－1.     

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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