醇碱联合解聚废聚酯的机理分析

指出PET在EG和路易斯碱同时存在下,PET的解聚反应是醇解反应与碱解反应相互协同、互为促进的过程,其解聚速度与解聚率得到显著提高,解聚及回收TPA、EG工艺条件简化。实验表明在常压、180℃、30min内,PET解聚率可达99％,其解聚产物的颜色深浅主要受体系碱度、反应温度和反应时间的影响,通过选择不同的路易斯碱、调整解聚工艺条件可有效控制有色物质的生成总量。     

甲醇超临界水氧化的实验研究

以过量的双氧水作为氧化剂,进行了380,400,420℃三个温度的超临界水氧化处理甲醇废水的实验研究。随着温度升高甲醇和COD去除率速度增加,在420℃时120min甲醇和COD的去除率都可达到99％以上。380℃时直到180min甲醇和COD的去除串分别为96．3％和93．1％;400℃到150min时甲醇去除半达到97.5％,到180min时COD去除率也达到了98．7％。在甲醇的氧化分解历程中,经历了先被氧化分解为甲醛的中间过程,然后再被完全氧化为二氧化碳和水。     

多元醇解聚废弃PET优化条件

采用红外吸收光谱仪和质谱仪,分析在不同条件下多元醇解聚聚酯PET对得到中等分子量PET降解产物结构的影响,并用端基分析法测试表征不同条件下反应得到的PET产物的环氧值和平均分子量。通过分析和对比,得出PET解聚产物的结构性能和得到中等分子量PET解聚最佳工艺:温度在280℃左右,催化剂Zn(AC)2·2H2O占PET重量的0.15%,物料配比多元醇用量是废弃PET质量的3.5倍,解聚时间在3h左右,并且解聚产物比较纯净,环氧值(EV)可达0.336,平均分子量(M)降为296。     

利用废弃聚酯(PET)制备对苯二甲酸二甲酯(DMT)

利用废弃聚酯在乙二醇介质中解聚,其解聚温度为160～200℃,催化剂醋酸锌用量一般为0.03％～0.1％,得到的中间产物为对苯二甲酸双羟乙酯单体(BHET)及少量齐聚物。BHET含量(在一定时间内)随解聚时间增加而增大,解聚温度为200℃时,解聚所需时间最短。分离除去乙二醇后的中间产物与过量甲醇发生酯交换反应,反应温度为58～70℃,催化剂氢氧化钠用量一般在0.05％～0.15％之间,得到的产物DMT含量为96％～98％。     

使用CO2对拜尔法赤泥脱钠的无害化工艺

通过使用CO2脱钠实验对拜尔法赤泥脱钠无害化工艺进行探讨,以脱钠率为研究指标,分析反应温度、反应时间、固液比、CO2气流量和赤泥粒度5个因素对脱钠率的影响。研究结果表明,合理的脱钠工艺参数为：反应温度25℃、反应时间100min、固液比1/5、CO2气体流量0.8L/min和细磨的赤泥粒度;该工艺下的脱钠率为76.12%,残余Na2O含量为2.5%,NaHCO3溶液浓度约为4%。相比传统工艺,该处理工艺简单,经该工艺处理赤泥浆pH值由10.2降至7.1,实现了赤泥无害化,又降低了温室气体CO2排放,并可进行回收NaHCO3,有利于资源的循环利用。     

二次铝灰制备α-Al_2O_3工艺

探索了以二次铝灰为原料,通过低温碱性熔炼—浸出—晶种分解制备α--Al2O3工艺.研究了碱灰比、盐灰比、熔炼温度、熔炼时间、浸出温度、浸出时间和固液比等因素对铝及硅浸出率的影响.探讨了使用晶种分解法处理浸出液制取氧化铝的工艺的可行性.结果表明:优化制备条件为碱灰比1.3,盐灰比0.7,熔炼温度500℃,熔炼时间60 min,浸出温度60℃,浸出时间30 min,固液比1∶4;铝浸出率最高可达92.71%;晶种分解法处理浸出液的后续工艺可行有效.     

赤泥使用石灰窑尾气脱碱的模拟实验

通过对山西某铝厂赤泥的基础特性分析,提出用含CO2为20%左右的石灰窑尾气对赤泥进行脱碱模拟实验。热力学分析表明利用石灰窑尾气脱碱是可行的,而实际影响脱碱的主要为动力学因素。实验以脱碱率为指标,分析液固比、CO2体积分数、CO2摩尔比、搅拌速度和反应温度5个因素对赤泥脱碱率的影响。研究结果表明,合理的脱碱工艺参数为:液固比8mL/g、CO2体积分数20%、CO2摩尔比40、搅拌速度400r/min和反应温度60℃,该工艺条件下的脱碱率为31.10%。实验结果表明,可以利用含CO2为20%左右的石灰窑尾气对赤泥进行脱碱处理,该工艺能脱除赤泥中的可溶性碱,符合"以废治废"的循环经济理念。     

非水条件下有机碱分解氯化铵回收氨的工艺

采用有机碱在非水条件下将纯碱工业副产的NH4Cl分解为NH3和HCl,研究了在异丙醇溶剂中三辛胺(TOA)分解NH4Cl释放NH3的工艺,考察了反应温度、N2流量、TOA与NH4Cl摩尔比、异丙醇与TOA摩尔比、反应时间等对NH4Cl分解反应的影响。结果表明:NH4Cl处理量为0.1 mol时的最佳分解工艺条件为反应温度353 K、N2流量120 mL/min、TOA与NH4Cl摩尔比为1.4∶1、异丙醇与TOA摩尔比为7.1∶1、反应时间8.25 h。在最优条件下,NH3收率达到97%以上,且无废水排放。进一步探讨了极性溶剂下有机碱分解NH4Cl的反应机制,发现溶剂异丙醇中羟基与TOA中N原子上的孤对电子形成氢键,使TOA的碱性增强,与NH4Cl反应更容易释放出NH3。     

利用工业废盐酸与低品位菱锰矿生产氯化锰的试验研究

介绍了以工业废盐酸和低品位菱锰矿为原料制取氯化锰的工艺研究.通过对酸浸过程的理论与试验研究,讨论了各种因素对锰浸出率及产品质量的影响,得出最佳工艺条件.试验结果表明,在反应温度为80℃、液固比2.5:1、酸的过量系数1.3、时间60min条件下锰浸出率为90%左右,氯化锰产品质量符合HG/T 3816-2006标准要求.     

废盐酸浸出菱锰矿制取四水氯化锰实验研究

介绍了以遵义钛业的废盐酸为原料浸出菱锰矿的工艺,考查了各种因素对锰浸出率的影响.实验结果表明在浸出时间60min,浸出温度80℃,液固比2.5:1,酸过量系数1.3的最佳工艺条件下,锰的浸出率可达90.14%,浸出液经过除杂结晶后,产品可以达到现行的工业级四水氯化锰的行业标准.     

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.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

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     

Journal of Donghua University ( English Edition) Contents of Volume 31

正~~