烷基苯氯甲基化反应

以甲苯、乙基苯、异丙基苯为原料,ZnCl2和盐酸为催化剂,多聚甲醛和盐酸组成氯甲基化试剂,通过氯甲基化反应合成了甲基苄氯、乙基苄氯和异丙基苄氯,探讨了原料比、催化剂用量、反应温度、反应时间等因素对烷基苯氯甲基化反应的影响,确定了烷基苯氯甲基化反应的最佳条件为:烷基苯与多聚甲醛的摩尔比为4∶1,催化剂ZnCl2的摩尔用量为多聚甲醛的0.6倍,盐酸用量为6 mL,反应温度为60℃,反应时间为6 h;在此条件下3种苄氯的收率分别可达84.9%、90.6 0A和86.7%.     

三甲胺催化多聚甲醛与正丁醛制备2,2-二羟甲基丁醛

以多聚甲醛为原料,在三甲胺的催化下与正丁醛发生羟醛缩合反应制备2,2-二羟甲基丁醛.GC、GC-MS分析发现2,2-二羟甲基丁醛为主产物、2-乙基丙烯醛为最主要的副产物.通过对无机碱、有机碱催化剂进行筛选,发现三甲胺水溶液为较优催化剂.当以10%的水为反应溶剂,多聚甲醛∶正丁醛∶三甲胺=2.5∶1.0∶0.050(摩尔比)时,在80℃反应2 h后,正丁醛转化率为91%,2,2-二羟甲基丁醛的选择性为78%,得率为71%.以固体甲醛替代甲醛水溶液有利于减少含醛废水的排放,符合绿色化学的发展趋势.     

BF3-乙醚催化合成2-甲基-5,6-二氢-2H吡喃

介绍了以多聚甲醛、间戊二烯为原料在乙酸乙酯中BF3-乙醚溶液催化作用下,进行Diels-Alder反应,合成了2-甲基-5,6-二氢-2H吡喃的方法.考察了催化剂和溶剂、反应温度、时间等因素对收率的影响.结果表明,在多聚甲醛用量28 g、间戊二烯112 mL, BF3-乙醚溶液2.0～2.5 g,乙酸乙酯50～60 g,反应温度130～140 ℃,时间5 h,常压条件下,收率可达54%.     

钙钛矿型催化剂La_(0.7)K_(0.3)CoO_3催化合成甲基二氯化膦

研究了以钙钛矿型催化剂La0.7K0.3CoO3为催化剂,以甲烷和三氯化磷为原料合成甲基二氯化膦的反应,考察了影响反应的几种因素.结果表明,反应物n(CH4):n(PCl3)=5:1,反应温度300℃,催化剂粒径425～850μm为较适宜的反应条件.     

镇草宁压力釜室的设计

<正> 由于原料的特殊性和反应经历的复杂性,因而在反应过程中存在着许多不安全的因素,主要表现在: 1.多聚甲醛在一定的温度和酸度的条件下,逐级分解为单体甲醛,并伴随放出热量。由于甲醛分子中羰基与两个氢原子相连,所以它的化学性质比较活泼,在一定条件下遇到空气就能形成爆炸。甲醛的沸点为-21℃,闪点为54.5～93℃,其爆炸下限为7％。每个CH_2O单位的燃烧热为120.05千卡。甲醛系强刺激性物质,对人体有直接的危害。 2.三氯化磷系毒性很强的物质,直接危及人体呼吸道,当空气中每立方米含量超过4毫克时,就达危险极限。三氯化磷又是忌水性物质,在潮湿空气中会发烟,遇到水分将引起激烈的水解作用,生成亚磷酸和氯化氢气体,并伴随放热。 3H_2O+PCl_3→H_3PO_3+3HCl+66.7千卡 氯化氢气体具有强腐蚀性,对人体和设备有很大损害,而多聚甲醛中又含有水分,两种原料反应时存在着不安全因素。 3.在反应过程中,投料顺序、加料方式、原料所含水分的多寡、釜体充填系数的大小等影响安全的因素很多,操作上稍有不慎,将会造成事故。 4.多聚甲醛和三氯化磷的反应,工艺上要求在230℃、28个大气压左右的条件下进行,这在安全上有着一定难度。 通常反应速度可以用下式来表示:     

五元瓜环催化合成亚磷酸二烷基酯

以五元瓜环为催化剂,用三氯化磷与无水醇进行酷化反应合成亚磷酸二烷基酯。通过正交试验,得到最佳工艺条件：在以四氯化碳作为溶剂,醇／三氯化磷摩尔比为3,催化剂的用量为反应物总质量的1％,反应温度为50℃,反应时间为120min。在该条件下,合成了亚磷酸二乙酯、亚磷酸二甲酯、亚磷酸二正丙酯、亚磷酸异丙酯和亚磷酸二正丁酯,收率较好。     

固载型硅钨杂多酸催化剂的制备及性能研究

以ZrO2-MoO3为载体采用浸渍法制备了负载型硅钨杂多酸催化剂,用IR、XRD谱对该催化剂进行了表征,结果表明:杂多阴离子已被固载,且保持了Keggin结构.同时考察了该催化剂在合成乙酸丁酯反应中的催化活性.实验表明,制备的催化剂具有良好的催化活性.在酸醇比为1:1.5,催化剂用量为反应总物量的1.0%时,乙酸丁酯的收率达到85.4%.     

唑来膦酸的工业合成

以咪唑为起始原料,和氯乙酸乙酯经N-烷基化、水解、成盐得2-(1-咪唑基)乙酸盐酸盐(4),4再与磷酸、三氯化磷反应,然后精制得唑来膦酸(1),总收率为30.4%.合成的目标化合1,其结构经核磁共振氢谱、红外光谱、质谱及元素分析确证.与文献相比,改进后的路线操作简便,易于工业化,制得的产品纯度高.     

新型光敏催化剂用于甲苯侧链氯化反应

为提高目的产物收率及选择性，缩短反应时间，将新型光敏催化刑BMMB用于甲苯侧链的氯化反应，制取三氯甲苯．这种光敏催化剂有较强的反应活性和贮存稳定性，对设备无腐蚀作用．采用催化剂2，2’-偶氮二异丁腈、过氧化苯甲酰或三氯化磷时可知：2，2’-偶氮二异丁腈在反应中易消耗掉，需在反应中不断添加；过氧化苯甲酰储存和运输不稳定；三氯化磷沸点低，易分解失活，会阻碍制苯甲酰氯的水解反应，增加产物中磷残存量，且对设备有腐蚀作用．新型光敏催化剂BMMB没有上述缺点．含0．5％BMMB的甲苯在蓝光照射下于110～120℃氯化8h，三氯甲苯收率为95．5％～96．5％，优于2，2’-偶氮二异丁腈、过氧化苯甲酰和三氯化磷．     

乙酰苯胺及其衍生物的氯甲基化反应

考察了乙酰苯胺及其衍生物在多聚甲醛-盐酸体系下的氯甲基化反应, 结果表明, N-氯甲基化反应的产物是主要产物. 关键中间体及最终化合物的结构经核磁共振氢谱及碳谱确证.     

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     

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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Brief Introduction to “Journal of Jilin University( Science Edition) ”

<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has