薄层色谱法分析壳寡糖

建立壳寡糖的薄层色谱（TLC）分析条件。通过对各种展开剂的实验，确定壳寡糖的TLC最佳的展开剂是乙酸乙酯：乙醇：水：氨水=5：5：4：0.3。壳寡糖溶液上行展距为8cm，采用浸渍法显色。本文方法分离效果好，简便，重现性好。     

产壳聚糖酶菌株的筛选与鉴定

从自然界中采集土壤样品,通过富集培养,平板分离,壳聚糖酶活力及粘度快速测定,获得了3株高活力产壳聚糖酶菌株.采用薄层层析(TLC)分析了酶解产物,结果表明:水解产物中均含有壳寡糖.结合形态、生理生化特征鉴定及16S rDNA序列分析,初步确定其为Mitsraria(属)的一种.     

黄姜中鼠李糖的提取

以黄姜为原料对鼠李糖的提取工艺进行了研究.实验表明,采用发酵法对黄姜水解液预处理,可有效除去溶液中的葡萄糖.通过优化实验,得到分离提取鼠李糖的最佳条件为:水解液为50g/L稀硫酸溶液,水解时间2h;酵母菌发酵的pH值为6,发酵时间2h;黄姜中鼠李糖的提取率为1.5%.经薄层层析、核磁共振氢谱分析表明,制备的产品是鼠李糖.     

棉籽油制备生物柴油的研究及分析

 为建立适合新疆地产棉籽油制备生物柴油的工艺条件和检测产物的方法,本实验采用单因素和正交试验优化了棉籽油制备生物柴油的反应条件,确定最佳反应条件为:醇油物质的量比5:1,KOH用量1.1%,温度40℃,反应时间60min.在此条件下,产率不低于98.6%.并初次联合使用薄层层析色谱和高效液相色谱定性定量分析棉籽油和棉籽油生物柴油.试验结果表明,该色谱分析方法,样品组分分离效果好,且线性关系良好,相关性系数均在0.99以上.     

火麻仁油β-环的精包合物研究

采用饱合溶液法制备了火麻仁油β-环糊精包合物,以收得率、油利用率、包合率为指标,应用正交试验筛选出包合的最佳条件。经薄层层析、红外光谱法鉴定,证实火麻仁油与β-环糊精确已形成包合物。     

6–羧基壳寡糖清除活性氧的能力及作用机理

利用漆酶/TEMPO体系对壳寡糖(COS)分子进行选择性氧化,制备6–羧基壳寡糖(C-COS).通过傅里叶红外光谱(FTIR)、核磁共振波谱(13C NMR)及酸碱电导滴定对样品进行表征分析,并对6–羧基壳寡糖(C-COS)清除活性氧(ROS)能力进行探究.结果表明:漆酶/TEMPO体系成功将壳寡糖氧化为6–羧基壳寡糖...     

反相制备色谱法分离葛根素

葛根采用溶剂冷浸提取3次,每次48 h,提取物经酸水解获得粗品葛根素.粗品葛根素经反相制备色谱分离纯化,分离条件为:YWG-C18反相色谱柱(22×300 mm,30 μm), 流动相为甲醇,流速为2.0 mL/min,紫外检测,波长为270 nm,所得产品经薄层层析鉴定纯度.     

壳寡糖处理对油框奈果实采后贮藏品质的影响

研究分子量为3000 Da,质量浓度分别为2.5、5、10和15 g/L的壳寡糖溶液处理对油柜奈果实采后贮藏品质(硬度、色泽、可溶性固形物含量、失重率和腐烂指数)的影响.结果表明:5、10和15 g/L的壳寡糖溶液处理能延缓油柜奈果实硬度的下降和表面转色,减少果实失重和降低果实腐烂率.在所有处理中,用10 g/L壳寡糖处理的果实品质保持最好.因此,10 g/L壳寡糖处理可作为油柜奈果实在(25±1)℃、相对湿度90%条件下贮藏时的适宜处理条件.     

N-二异丙氧磷酰化壳寡糖的合成与表征

通过壳寡糖和二异丙基亚磷酸酯在一种温和条件下发生Atherton-Todd反应,成功制备出了一种新型的壳寡糖含磷衍生物N-二异丙氧磷酰化壳寡糖.探讨了水与无水乙醇的体积比、壳寡糖与三乙胺的摩尔比、壳寡糖与二异丙基亚磷酸酯的摩尔比以及反应时间等因素对产品含磷量的影响.最后,对最优条件下合成的产品进行IR、1H-NMR、13C-NMR以及31P-NMR的表征,证明二异丙氧磷酰基已经成功嫁接到了壳寡糖的氨基上.这种简单而有效的方法为N-磷酰化壳聚糖衍生物的制备提供了一条新的途径.     

植物油非皂化部分的分离、鉴定和测定

文冠果、威宁短柱油茶、油莎草、黄连木等植物油的非皂化物经硅胶柱层析或硅胶G离心薄层层析分离为四部分:烃类、三萜醇类、4-甲基甾醇类和甾醇类.三萜醇类、4-甲基甾醇类和甾醇类的乙酸酯用硝酸银-硅胶G薄层进一步分离.分离所得的多数个别组分采用薄层层析、气相色谱、熔点、比旋光度、红外光谱和质谱等进行鉴定.组分的定量测定采用气相色谱和高效液相色谱对照时基本符合.对采用的各种分离条件均加以详细讨论.     

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。     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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