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1.
采用以高纯硅胶为色谱柱,水-有机溶剂为流动相的亲水作用色谱模式,通过改变流动相中有机溶剂类型及浓度、酸类型、缓冲液pH值及离子强度,探讨了蒽环类碱性药物在该色谱模式下的保留机理.结果表明,在所考察条件下,溶质的保留机理主要为吸附及离子交换混合保留机理.  相似文献   

2.
以1-乙烯基咪唑和1-碘-1H,1H,2H,2H-全氟癸烷为原料合成了含氟表面活性剂——碘化1-乙烯基-3-全氟辛基乙基咪唑(VIMF).进一步将VIMF作为可聚合单体,利用巯基-烯点击反应,制备了VIMF键合硅胶色谱固定相(Sil-VIMF).采用傅里叶变换红外光谱和热重分析对Sil-VIMF固定相材料进行表征,结果证明了其成功制备.保留机制考察结果表明,Sil-VIMF固定相具有亲水作用色谱保留机制.色谱分离性能研究结果表明,Sil-VIMF固定相可实现酰胺类、核苷和核碱基类、苯胺类物质的良好分离,其柱效可达79 200 N/m.进一步将Sil-VIMF固定相用于胃癌细胞膜脂提取物的分离分析,可实现胃癌细胞膜中磷脂酰胆碱和磷脂酰乙醇胺的有效分离分析,显示了良好的应用潜能.  相似文献   

3.
亲水作用色谱分离表阿霉素时,在中性及弱酸性条件下,样品在硅胶柱上呈现不可逆吸附平衡过程.对影响不可逆吸附的因素如缓冲液的pH值、离子强度、有机溶剂的类型及流动相中水的含量进行了探讨,推断这种现象是由于溶质离子与固定相表面极少数的强活性硅羟基作用所致.不可逆吸附是在一定条件下产生的,可通过改变洗脱条件减小。  相似文献   

4.
从PMP萃取酸度、萃取次数探讨了柱前PMP衍生方法对单糖-PMP衍生物的影响,并从流动相比例、缓冲液pH值、缓冲盐浓度三个方面对单糖柱前衍生HPLC的分离效果进行了优化研究.结果表明:单糖进行PMP衍生后,用HCl中和至pH为7.0,能最大限度避免单糖-PMP衍生产物的损失;使用三氯甲烷萃取PMP三次时,能在除去PMP的情况下避免单糖-PMP衍生产物的损失;降低流动相中有机相的比例或提高缓冲液的pH值,有利于色谱峰分离度的提高;提高缓冲盐浓度,有利于保持色谱峰的对称性.  相似文献   

5.
建立C60-g-(乙二胺基)丙基键合硅胶填充柱毛细管电色谱法。研究操作条件如流动相组成、pH值对柱电渗流的影响.结果表明填充柱与流动相之间存在着快速平衡,可建立稳定的电色谱方法,并且填充柱可以在pH 2.5-7的范围内提供稳定的电渗流,有利于电色谱分离。  相似文献   

6.
一种新型两性离子交换毛细管液相色谱整体柱   总被引:2,自引:1,他引:1  
利用甲基丙烯酸和2-二甲基乙基胺甲基丙烯酸酯为功能单体,乙二醇二甲基丙烯酸酯为交联剂,通过在石英毛细管内原位聚合制备了1种新型两性离子交换液相色谱整体(MAA-EDMA-DAMA)柱.整体固定相表面正、负电荷密度受流动相pH影响,故通过调节流动相pH值可实现阴阳离子交换模式相互转换.当流动相pH6.0时,此整体柱表现出典型阴离子交换作用机理,聚合整体柱对一些无机阴离子如BrO3-、NO2-、Br-和NO3-有很好的选择性;当流动相pH7.0时,该整体柱表现出阳离子交换作用机理,对对甲苯胺、邻苯二胺、对氯苯胺、对硝基苯胺表现出高的选择性;当流动相中乙腈含量小于40%时,疏水作用和离子交换作用对有机离子的保留均有影响,为提高分离的选择性创造有利条件.  相似文献   

7.
用自由基聚合法制备了分别含有聚(N-异丙基丙烯酰胺/2-丙烯酰胺基-2-甲基丙磺酸)和聚(异丙基丙烯酰胺/甲基丙烯酸异丁酯/丙烯酸)的2种酸性温敏色谱填料.用热失重和元素分析表征了接枝率.用HPLC研究了异硫氰酸苯酯衍生化丙氨酸、缬氨酸、苯丙氨酸、色氨酸、精氨酸、亮氨酸等6种氨基酸的色谱保留行为.结果显示,采用纯水相为流动相,仅通过控制柱温即可实现分离,证明被分离物的色谱保留性质随温度的改变而变化,制得的色谱填料具有温度敏感性.  相似文献   

8.
基于多面体寡聚硅倍半氧烷-甲基丙烯酸羟乙酯poly(POSS-MA-co-HEMA)有机硅胶杂化整体柱,建立了典型苷类药物(连翘苷、豆腐果苷、紫丁香苷、天麻素)的亲水作用毛细管电色谱检测技术。考察了苷类药物的亲水作用,优化了流动相乙腈比例、缓冲液浓度、缓冲溶液pH、分离电压以及反压阀压力的影响,在最优条件(流动相为2 mmol/L磷酸三乙胺缓冲液(乙腈含量90%,pH=7.0),分离电压-8 kV、柱压力750 psi),4种苷类药物在10 min内得到了基线分离。连翘苷、豆腐果苷、紫丁香苷和天麻素线性范围分别为10~200 μg/mL、25~200 μg/mL、15~200 μg/mL和25~200 μg/mL, 检测限为1.5~8.0 μg/mL。应用于血清模拟样品分析,平均回收率为95.6%~99.1%,相对标准偏差小于3.3%。  相似文献   

9.
建立C60-γ-(乙二胺基)丙基键合硅胶填充柱毛细管电色谱法,研究操作条件如流动相组成,pH值对柱电渗流的影响,结果表明填充柱与流动相之间存在着快速平衡,可建立稳定的电色谱方法,并且填充柱可以在pH2.5-7的范围内提供稳定的电渗流,有利于电色谱分离。  相似文献   

10.
综述了高效液相色谱配体交换色谱手性固定相的发展、制备及其在手性拆分中的应用,讨论了洗速、进样量、中心金属离子及其浓度、流动相pH值、柱温、有机改性剂等对对映体分离的影响,阐述了对手性识别机理的认识。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
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.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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