模拟移动床色谱法分离C60的条件选择

用模拟移动床色谱对C60进行了分离.工作参数:直径1 cm长10 cm的半制备柱;固定相为ODS;残余液流速2.2 mL/min,萃取液流速2 mL/min,进样流速12 mL/h;室温;切除C60前杂质的流动相V(甲醇):V(甲苯)=60:40,切换时间14.5-15.5 min;切除C60后杂质的流动相V(甲醇):V(甲苯)=50:50,切换时间19.5-20.5 min;在上述条件下,对80%C60固体粉末进行分离,C60的纯度可达95%,收率大于70%.结果表明,这种方法是可行的,易于实现工业化.     

模拟移动床色谱法分离C60的条件选择

用模拟移动床色谱对C60进行了分离.工作参数:直径1 cm长10 cm的半制备柱;固定相为ODS;残余液流速2.2 mL/min,萃取液流速2 mL/min,进样流速12 mL/h;室温;切除C60前杂质的流动相V(甲醇):V(甲苯)=60:40,切换时间14.5-15.5 min;切除C60后杂质的流动相V(甲醇):V(甲苯)=50:50,切换时间19.5-20.5 min;在上述条件下,对80?0固体粉末进行分离,C60的纯度可达95%,收率大于70%.结果表明,这种方法是可行的,易于实现工业化.     

模拟移动床色谱法分离C60的条件选择

用模拟移动床色谱对C60进行了分离。工作参数：直径1cm长10cm的半制备柱;固定相为ODS;残余液流速2．2mL/min,萃取液流速2mL／min,进样流速12mL/h;室温;切除C60前杂质的流动相V（甲醇）：V（甲苯）=60：40,切换时间14．5—15．5min;切除C60后杂质的流动相V（甲醇）：V（甲苯）=50：50,切换时间19．5—20．5min;在上述条件下,对80％C60固体粉末进行分离,C60的纯度可达95％,收率大于70％。结果表明,这种方法是可行的,易于实现工业化。     

聚苯乙烯凝胶色谱法快速检测硫酸头孢噻利中缩合物杂质

采用聚苯乙烯基质的凝胶色谱柱对硫酸头孢噻利中的缩合物杂质进行分析。色谱柱使用MKF-GPC-300柱(300 mm×7.8 mm,7μm),流动相V(甲醇)∶V(水)=75∶25,流速1.0 mL/min,检测波长254 nm。液相色谱-质谱联用(LC-MS)结果表明:硫酸头孢噻利与其缩合物杂质实现了良好的分离,分析时间不到15 min,且方法、实验条件简单,操作方便,能快速有效地实现硫酸头孢噻利与其缩合物杂质的分离。     

高效液相色谱法分离邻、对位硝基甲苯同分异构体

利用高效液相色谱法对邻硝基甲苯和对硝基甲苯2种同分异构体的分离作了系统的研究.选择十八烷基键合相色谱柱COSMOSIL5C_(18)-AR-Ⅱ(6.0mm×250mm),甲醇作为样品溶剂,甲醇和水的混合物作为流动相.确定了分离的最佳色谱条件为室温、V(甲醇)∶V(水)=70∶30、检测波长278nm、流动相流速1.0mL/min.回收率验证结果显示,准确度和灵敏度均符合分离要求.     

小鼠血浆中三七皂苷C质量浓度的测定方法

给出了血浆中三七皂苷C质量浓度的测定方法:采用甲醇提取法从血浆中提取三七皂苷C,以原人参二醇为内标物;采用RP-HPLC法测定质量浓度,用ODSC18色谱柱(4.6mm×250mm,5μm),以V(甲醇)∶V(水)=90∶10为流动相,流速1.0mL/min,检测波长203nm.结果表明:三七皂苷C和原人参二醇的保留时间分别为13.6min和23.6min,色谱峰之间达到基线分离,且不受空白血浆中其他成分的干扰;日内精密度RSD均小于4.38%,日间精密度RSD均小5.22%,方法回收率为95.2%～99.1%.     

模拟移动床色谱提纯槲皮素

运用模拟移动床色谱分离技术,提取银杏叶水解物黄酮苷元中的槲皮素,在洗脱液配比为甲醇∶水=7∶3(体积),进样流速uF=0.1 mL/min,冲洗流速uP=3.0 mL/min时,去除前杂质的洗脱流速uD=1.0 mL/min,切换时间tS=9 min;去除后杂质的洗脱流速uD=0.8 ,L/min,切换时间tS=14 min.经HPLC检测,产品中槲皮素质量分数达90%以上.     

长链烷基甲基萘单磺酸盐和双磺酸盐分离研究

采用反相离子对高效液相色谱(HPLC)及电喷雾质谱(ESI-MS)研究了辛基甲基萘单、双磺酸盐的分离提纯效果.经过大量色谱分析实验,找到了最佳分析条件.紫外检测波长为230nm,流动相为甲醇和水的混合物,流速为0.8mL/min,采用梯度洗脱的方法进行分析.洗脱条件为线性梯度:0~40min,V(甲醇)∶V(水)=60∶40;40~50min,V(甲醇)∶V(水)=100∶0.在此优化条件下样品分离度高,分离效果好.用面积归一化法得到了样品各组分的相对含量,采用HPLC和ESI-MS对组分进行了分析和表征.建立了一种便捷、可靠的烷基甲基萘磺酸盐的分析表征方法以及单、双磺酸盐分离提纯效果的评价方法,得到了满意的结果.     

替考拉宁工业分离色谱条件选择

讨论了糖肽类抗菌素(替考拉宁)工业分离色谱条件,对参数进行了系统的测试与优化,柱的尺寸为5cm×10cm,流动相为甲醇和水(体积比60∶40,pH值6-7),固定相为C18,6nm;进样体积15mL及进样流速20mL/min等.结论为采用模拟移动床分离提供了基础.     

HPLC法测定盐酸莫西沙星片中光降解杂质的含量

目的高效液相色谱法(HPLC)测定盐酸莫西沙星片中光降解杂质2'-氧代莫西沙星的含量。方法采用Agilent Poroshell EC-C18色谱柱,四丁基硫酸氢铵缓冲液:甲醇(90∶10)(V/V)为流动相A;甲醇∶四丁基硫酸氢铵缓冲液(90∶10)(V/V)为流动相B;流动相A为稀释溶剂;采用等度洗脱,检测波长为247 nm;柱温30℃;进样体积20μL;流速1.3 mL/min,测定盐酸莫西沙星片中光降解杂质2'-氧化莫西沙星的含量。结果 2'-氧代莫西沙星测定质量浓度在0.151～2.517μg/mL范围内呈良好的线性关系,线性方程为y=0.297x-0.016(r=0.999 5),检测限和定量限分别为1.510和3.021 ng,杂质回收率在限度质量分数50%,100%和150%3个回收率水平均在90%～110%之间,平均回收率为98.6%;相对标准偏差(relative stanard deviation,RSD)为1.51%(n=9),该方法准确度良好。结论该方法适用于盐酸莫西沙星片中光降解杂质2'-氧代莫西沙星的检测。     

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.     

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.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

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-