丁基膦酸单丁酯稀土络合物的振动光谱研究

用稀土氯化物与丁基膦酸二丁酯反应制备了标题络合物Ln(BBP)3(Ln=La,Eu,Yb),测量了络合物4 000~100 cm-1的红外光谱和1 500~100 cm-1的拉曼光谱,对其主要红外吸收和拉曼谱带进行了归属.指认151cm-1的红外吸收带为Ln—O键的伸缩振动带,1 138 cm-1的红外吸收和1 136 cm-1的拉曼谱带为PO2基团的反对称伸缩振动带(aνsPO2),1 088 cm-1的红外吸收谱带为PO2基团的对称伸缩振动带(sνPO2).提出了络合物的每个稀土离子与邻近的三个稀土离子通过双—O—P(C4H9)(O C4H9)—O—桥相连接,形成“双桥二十四元环”多聚网络结构的假设模型.Ln—O键基本上为离子键.     

新型深度共熔溶剂选择性分离木质素的研究

近年来,以胆碱类为代表的生物基离子液体作为木质素的优良溶剂逐渐受到广泛关注.文中基于Hansen溶解理论,设计出一种分别以乳酸(LA)和氯化胆碱(Ch Cl)为氢键供受体的新型离子液体——深度共熔溶剂(DES)作为木质素分离的溶剂.通过实验考察了常压下Ch Cl/LA摩尔比、温度、时间对木质素溶解效果的影响,确定了最佳工艺条件为Ch Cl/LA摩尔比1∶9、温度90℃、时间12h,此时木质素的溶解率达90.1%,再生木质素纯度为96.3%.紫外可见光谱(UV)及红外光谱(FT-IR)分析表明木粉中木质素经DES处理后被大量脱除;X射线衍射分析表明经预处理后的木粉中纤维素结构基本未被破坏;核磁共振谱(13C NMR)分析表明再生木质素由紫丁香基、愈创木基及少量对羟苯基结构单元组成;离子色谱分析结果表明该混合溶液中的综纤维素只有少量发生溶解.     

裂褶多糖的乙酰化及光谱分析

采用吡啶-乙酸酐反应体系,以二甲基亚砜为溶剂,合成不同取代度的毫克级乙酰化裂褶多糖,并对改性前后样品的光谱特征进行分析.其红外光谱在1735~1729 cm-1出现酯基的C O伸缩振动,在1251 cm-1处出现一个较弱的酯基的CO伸缩振动,且CO伸缩振动随着乙酸酐用量的增加略向高波数移动;其紫外-可见光谱在252~272 nm处存在一个弱的羰基吸收峰.其1HNMR峰在2.6和5.1的化学位移证实发生了乙酰化取代.采用凝胶渗透色谱测定改性前后裂褶多糖的相对分子质量,发现改性后样品的相对分子质量显著降低,且分散程度减小.由于取代度和相应的特征吸收值不呈线性关系,试验条件下未能建立紫外和红外光谱法测定乙酰化裂褶多糖取代度的计算公式.     

1-(6-乙酰基-9-正丁基咔唑-3-基)-3-苯丙基-1,3-二酮的合成及其光谱性能

β-二酮化合物被广泛应用于有机稀土配合物的配体,配体的最低三重态能级与稀土的最低激发态能级的匹配程度直接影响有机稀土配合物的荧光强度,为了提高有机稀土配合物的荧光强度,设计合成新的β-二酮化合物变的尤为重要。本文以咔唑为原料,经N-烷基化、乙酰化和缩合反应得到1-(6-乙酰基-9-正丁基-9H-咔唑基)-3-苯丙基-1,3-二酮。经氢核磁共振谱(1 H-NMR)、质谱(MS-ESI)和红外光谱(IR)确认,目标化合物结构正确,并测定了化合物的紫外吸收光谱、热重(TG)、示差扫描量热曲线(DSC),结果表明该化合物适合用于有机稀土配合物的配体。     

基于光谱法的脾虚胀满合剂指纹图谱研究

建立脾虚胀满合剂的紫外—可见指纹图谱及红外指纹图谱,提升其质量标准,采用紫外可见分光光度计和红外光谱仪分别测定10批次脾虚胀满合剂,建立脾虚胀满合剂的对照紫外—可见指纹图谱和对照红外指纹图谱,采用相关系数法计算脾虚胀满合剂样品指纹图谱与对照指纹图谱的相似度.结果显示,含量符合规定的样品,其吸光度满足200 nm(0.954~1.371 Abs)、223 nm(0.477~0.687 Abs)、252 nm(0.122~0.174 Abs)、282 nm(0.248~0.361 Abs)、308 nm(0.104~0.149 Abs),且紫外—可见图谱与对照图谱的相似度大于0.925,红外图谱与对照图谱的相似度大于0.861.实验表明,紫外—可见指纹图谱联合红外指纹图谱可以用于脾虚胀满合剂的质量评价.     

造纸黑液中木质素的分离与结构表征

为了综合利用造纸黑液,分别采用H2SO4溶液和H3PO4溶液从黑液中沉淀粗木质素,并分别用苯-乙醇溶液和丙酮溶液对其抽提纯化.考察了采用不同酸沉淀及溶剂抽提对木质素得率的影响,并对黑液木质素进行了元素分析、傅里叶红外光谱分析、13C NMR以及1H NMR等结构表征.实验结果表明:采用不同酸沉淀及溶剂抽提得到的木质素结构相差不大,采用H2SO4沉淀及苯-乙醇抽提方法制备的苯-乙醇木质素得率最高;黑液木质素含有较多的愈创木酚-紫丁香酚单元结构,呈现明显的硬木木质素特征;在苯-乙醇木质素与丙酮木质素中,苯丙烷结构单元经验式分别为C9H12.61O1.1(OCH3)1.43和C9H13.33O2.10(OCH3)1.38,每个C9单元中的β—O—4键仅为0.28和0.27个,β—β键仅为0.15和0.11个;黑液木质素中羟基和羧基数量较磨木木质素丰富.黑液木质素具备多种活性官能团,表现出与磨木木质素不同的结构特征,应用前景广阔.     

1,4-环己烷二甲醇型聚碳酸酯二元醇的合成与表征

以1,4-环己烷二甲醇(CHDM)、碳酸二乙酯(DEC)、1,4-丁二醇(BDO)和1,6-己二醇(HDO)为原料,以钛酸正丁酯(TBT)为催化剂,通过酯交换反应分别合成了聚1,4-环己基碳酸酯二醇(PCHDL)、1,4-环己基-丁基碳酸酯二醇(PCHBDL)和聚1,4-环己基-己基碳酸酯二醇(PCHHDL)。通过傅里叶红外光谱(FT-IR)、核磁氢谱(1H-NMR)、热重(TG)、差示扫描量热(DSC)及羟值与分子量测定等方法对产物进行了表征。结果显示所合成的聚碳酸酯二元醇产物分子量分别为1063 g/mol、1376 g/mol、1553 g/mol,FT-IR结果表明产物结构具有碳酸酯基与羟基,为聚碳酸酯二元醇的典型结构,与1H-NMR所表明PCHDL、PCHBDL和PCHHDL的结构一致。聚碳酸酯二元醇产物初始热分解温度大于200℃,玻璃化转变温度范围为-33.2℃～0℃。     

三种不同来源木质素的结构分析

通过红外光谱和核磁共振氢谱分析了三种不同来源木质素的结构,发现针叶材木质素中含有大量的愈创木基丙烷结构,而没有紫丁香基丙烷结构的存在;阔叶材木质素和草本木质素中既有愈创木基丙烷结构也有紫丁香基丙烷结构。     

稻草木质素的硫酸法提取与表征

用硫酸法提取农作物废弃物稻草中的木质素,采用质量分数72%的硫酸,以15(mg)∶1(L)的液固单位比,室温下反应2 h,得到产率9.23%的木质素.利用扫描电镜(SEM)、综合热分析、傅里叶红外光谱(FTIR)和氢核磁共振波谱(¹H-NMR)分析手段表征木质素的物理性质和化学结构,结果表明:木质素呈表面粗糙且有大量孔隙的不规则块状结构,在175~700 ℃内发生热解,分子结构中存在着大量羟基、羰基和醚键等活性官能团,属于对羟基苯基-愈创木基-紫丁香基型木质素.     

氟化非晶碳氢薄膜的红外结构及其电学特性

通过感应耦合等离子体(ICP)化学气相沉积方法并利用C4F8和H2的混合气体制备了氟化非晶碳氢(a C:F,H)薄膜.使用红外光谱仪分析了薄膜的结构.研究了金属Al/a C:F、H/SiMIS结构在不同环境光和不同频率下的电容 电压(C V)特性.红外结果表明,在800cm～1800cm-1和2700～3100cm-1的波数范围内,薄膜存在大量的C——C、C—F和C—H的振动结构.从薄膜的C V曲线的计算结果表明,薄膜当中的缺陷电荷约为1.07×1010cm-2,这些电荷主要局域在C——C双键周围 同时,由于界面陷阱电荷的存在,使得C V曲线随着测试频率的增加向负偏置方向偏移.     

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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