3-羧甲基绕丹宁的合成研究

该文以甘氨酸与二硫化碳为原料 ,将加成、取代、环合等三步反应直接在“一锅”内完成 ,得到 3 -羧甲基绕丹宁 ,并且采用相转移催化剂对合成工艺进行了改进 ,通过正交实验考察了多个因素对 3-羧甲基绕丹宁合成收率的影响 ,使收率提高到 85 .3% ,简化了合成工艺 ,缩短了反应时间 ,避免使用有机溶剂 ,提高了收率 ,降低了成本。     

相转移催化法制备环己酮

以次氯酸钠作为氧化剂,用不同的相转移催化剂,选择出最合适的条件,进行氧化环己酮制备环己酮的反应。结果表明：以四丁基碘化铵为催化剂制备环己酮的收经最高,可达８７．９％,制备环己酮收率的高低取决于所用的相转移催化剂的种类,选用的溶剂,环己醇与次氯酸钠的比例,反应时间和反应温度。     

完全脱乙酰度壳聚糖的制备及表征

采用二甲亚砜-氢氧化钠为反应体系,水为相转移催化剂,研究了相转移催化剂用量、甲壳素与氢氧化钠的质量比(投料比)、反应温度、反应时间、表面活性剂用量等因素对制备完全脱乙酰度壳聚糖的影响。结果表明：在催化剂用量为1．5mL,反应温度为130℃、投料比为1：2(m：m)、反应时间为3h,每100g甲壳素中加入5g十六烷基三甲基溴化铵阳离子表面活性剂,可制得完全脱乙酰度的壳聚糖。用红外光谱(IR)、X-光电子能谱(XPS)对完全脱乙酰度壳聚糖的结构进行了表征,结果表明：壳聚糖分子中的-NHCOCH3已全部转为-NH2。     

相转移催化合成乙酸异丁酯

利用相转移催化剂催化合成乙酸异丁酯．最佳反应条件如下：催化剂用量0．5g／0．1mol异丁醇、酸醇比1．2：1．反应时间100分钟．收率77．36％。实验证明，相转移催化对该酯化反应是高效、低成本和实用的合成方法。     

PTC法制备异戊烯基苄基醚

本文报道了苄醇、氯代异戊烯和氢氧化钠在相转移催化剂存在下反应得到异戊烯基苄基醚。反应迅速,条件温和,收率高。提出了反应的可能机理。考察了催化剂种类、碱的浓度、碱的用量和反应时间对反应的影响。     

相转移催化合成乙酸异丁酯

利用相转移催化剂催化合成乙酸异丁酯,最佳反应条件如下:催化剂用量0.5g／0.1mol异 丁醇,酸醇比1.2:1,反应时间100分钟,收率77.36％。实验证明,相转移催化对该酯化反应是高 效、低成本和实用的合成方法。     

相转移催化剂催化合成大红粉颜料的研究

研究了以色酚AS、苯胺和亚硝酸钠为原料,以十二烷基硫酸钠(SDS)、十二烷基磺酸钠(DBS')、十二烷基苯磺酸钠(SDBS)为相转移催化剂,通过重氮化反应和偶合反应催化合成大红粉颜料;探究了相转移催化剂种类、催化剂用量、反应时间对大红粉颜料产率的影响;实验结果表明:加入相转移催化剂的产物产率均明显提高,且混合催化剂(SDS和SDBS)催化性能最好,在反应中无明显起泡现象;相转移催化剂最佳用量为0.1 g,最佳反应时间为30 min,产率可达88.1%;方法具有操作简单、反应速度快、产物收率高、产品纯度好等特点。     

相转移催化合成橙花素

报道了以溴乙烷和β-萘酚为原料,在相转移催化剂聚乙二醇(PEG-600)催化下合成橙花素的方法.考察了反应温度,相转移催化剂用量,反应物摩尔比,反应时间对产率的影响.当相转移催化剂用量为反应底物β-萘酚摩尔数的5%,β-萘酚与溴乙烷摩尔比为1∶1.2,反应温度为70℃,反应时间为5h时,产物收率可达到67.0%.     

相转移催化合成S－烃基异硫脲盐

在相转移条件下，由硫脲与卤代烃合成了不同烃基的Ｓ烃基异硫脲盐。结果表明，在相同条件下，与无相转移催化剂相比，产品收率可提高３８％，且具有反应时间短、产品易于纯化等优点     

相转移催化合成苄叉丙酮

本文利用相转移催化剂十六烷基三甲基溴化铵(CTMAB)催化合成苄叉丙酮,最佳反应条件为:醛酮摩尔用量比为1:2,反应时间为40min,催化剂的用量为2.5g,收率达94.6%。实验证明,相转移催化合成对该反应是高效、低成本和实用的方法。     

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.     

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     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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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