醋酸甲酯催化精馏水解新工艺的工业试验及计算机模拟

在醋酸甲酯催化精馏水解新工艺取得中试成功基础上进行工业试验研究.催化精馏塔塔径1000mm、塔高22000mm;催化精馏段填充阳离子交换树脂催化剂捆扎包,提馏段填充波纹丝网填料.试验研究了进料水酯比、回流进料比和空速对酯分解率和水解液中酸水比的影响.新工艺使醋酸甲酯的水解率由固定床老工艺的23%-25%提高到57%-64%.应用模拟计算软件对试验过程进行了计算机模拟.     

乙酸甲酯催化精馏水解新工艺的工业应用

乙酸甲酯催化精馏水解工艺在水酯比为 2 .0 ,回流进料比为 1.8～ 2 .5 3,空速为 0 .44 2m3 (m3 ·h)的范围内 ,酯的水解率大于 5 7%,水解产物中酸水比大于 1.3(质量分数 ) .与传统的固定床水解工艺相比具有明显的优势 .     

乙酸甲酯水解塔催化剂装填方式研究

以离子交换树脂作催化剂,对乙酸甲酯(MeOAc)催化精馏水解塔几种催化剂装填方式进行了实验研究.比较结果表明,采用"管式"装填催化剂所得水解效率较高.采用"管式"方法装填催化剂,测得工业原料(乙酸甲酯与甲醇的共沸液)直接进料水解过程在空速0.351 h-1、回流进料比3.0(体积比)和进料水酯比5.1(摩尔比)的条件下水解率可达80%(摩尔数).     

用纤维素酶改善烟用醋酯纤维的表面性能

为了提高烟用醋酯纤维的降焦减害性能，采用纤维素酶对烟用醋酯纤维进行表面处理，通过水解达到醋酯纤维表面的改性，增加其比表面积，提高了吸附过滤性能。     

β-环糊精-组氨酸衍生物模拟DNaseⅠ催化DNA水解

合成了β－环糊精（β－CD）的组氨酸（His）一取代和二取代衍生物（简写β－CD－His）和β－CD－His2）并对其结构进行了表征，用该衍生物模拟DNaseⅠ对DNA进行了催化水解，并与DNaesⅠ催化水解DNA进行了比较，结果表明：2种β－环精精－组氨酸衍生物均能水解DNA，但比DNaseⅠ的活性要低，通过对水解产物的分析，发现水解机制类似于外切酶从DNA链的一端逐个断裂酸酯键。     

有机硼酸酯添加剂的水解稳定性及摩擦特性

有机硼酸酯作为新型多功能润滑油添加剂受到广泛重视。但硼酸酯易水解,使其在实际应用中受到限制。为此,从分子设计出发,合成了几类含Ｎ 或Ｏ 的内配位硼酸酯,用３ 种方法测定其水解稳定性,并与普通硼酸酯及外配位硼酸酯相比较,总结了硼酸酯的水解规律,实验结果表明,含氮配位硼酸酯的水解稳定性大大高于不含氮的普通硼酸酯和含受阻酚基团的硼酸酯;而内配位硼酸酯的水解稳定性明显好于外配位硼酸酯。同时,摩擦试验表明,含氮硼酸酯的减摩、抗磨性比普通硼酸酯有明显改善。     

新型分子印迹模拟抗体酶对羧酸酯的催化水解

以甲基膦酸对硝基苯酯作为分子印迹聚合物的模板分子,N-苯基-苯甲酰胺作为功能基,通过嵌埋ZnO纳米材料合成了具有"纳米通道”的新型分子印迹模拟抗体酶MIP-3.研究该酶对羧酸对硝基苯酯催化水解动力学结果表明,这类模拟抗体酶不仅具有很好的结构选择性,而且催化羧酸酯水解的能力大大提高.为合成分子印迹模拟酶和纳米材料的应用提供了新途径.     

脂肪酶催化米糠油水解反应的研究

研究了Candida sp. 99-125脂肪酶催化米糠油水解反应,考察了米糠油水解反应过程中水油比、酶用量和反应温度对酶促油脂水解的影响,并且研究了添加剂Ca(OH)₂对酶促油脂水解反应的影响。结果表明,最适合水解条件为水油比1.2、酶用量0.3%和反应温度40℃,反应48 h后的水解率为90.6%。酶促油脂水解反应中添加油重2.6%的Ca(OH)₂,反应24h后的水解率为93.3%,反应产物中脂层成份单甘脂（MAG）、二甘酯(DAG)和三甘酯（TAG）的质量分数分别为0.7%、1.4%和4.6%,添加Ca(OH)₂缩短了酶促水解反应时间,提高了酶促水解反应速率和水解率。     

超(近)临界条件下醋酸甲酯的水解工艺

近临界水与有机物的优异互溶和对有机反应的酸碱催化能力，为绿色化学合成工艺的开发提供了良好的契机。本文以醋酸甲酯水解为研究对象，在管式及釜式反应器中，采用工业装置的进料水酯比，研究了在超(近)临界条件(523—673K，23—32 MPa)下的反应行为，同时利用反应区域相分离技术改善了反应后期的转化率。实验结果表明，醋酸甲酯水解能够在150-200s停留时间范围内接近反应平衡转化率(水酯摩尔比2：1时转化率达到41％)，无需外加酸性催化剂，通过加入相分离介质苯，在短停留时间内转化率能提高3％。与现有水解工艺比较表明，超临界水解工艺在技术上有较高竞争力。     

淀粉硬脂酸酯的制备

采用二次添加硬脂酸甲酯的水溶剂法，在氮气保护下使淀粉水解物与硬脂酸甲酯发生酯交换反应，制备淀粉硬脂酸酯，对水解淀粉的平均聚合度、硬脂酸甲酸的用量、催化剂种类及用量、反应温度反应时间和产品酯化度的关系进行了研究。     

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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