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1.
采用甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,合成了具有高选择性的L-帕珠沙星分子印迹聚合物.印迹聚合物对模板分子的结合量明显高于空白聚合物.通过Scatchard分析研究了聚合物的选择结合性能,结果表明:分子印迹聚合物在识别帕珠沙星分子的过程中存在两类结合位点;用多点结合模型进行计算得到高亲和力的结合位点的离解常数Kd,1和最大表观结合常数Qmax,1分别为23.08 μmol/L和3.65 μmol/g,低亲和力的结合位点的离解常数Kd,2和最大表观结合常数Qmax,2分别为0.43 mmol/L和27.28 μmol/g.实验表明,分子印迹聚合物对模板分子的结合量高于其他类似物,呈现出空白聚合物没有的高选择性.  相似文献   

2.
以聚乙烯醇1735为分散剂、利福平为模板分子、甲基丙烯酸为功能单体、乙二醇二甲基丙烯酸酯为交联剂,用水溶液微悬浮聚合法制备了利福平分子印迹聚合物微球;在水溶液中,利用静态平衡结合法和Scatchard分析法研究了印迹聚合物的结合能力和选择性.结果表明,利福平溶液的浓度范围在5×10-5~1×10-4mol/L内,所制得的印迹聚合物内存在两类不等价的结合位点,根据实验数据计算得到高亲和力结合位点的离解常数和最大表观结合量分别为Kd1=1.08×10-2mg/mL和Qmax1=14.40 mg/g;低亲和力结合位点的离解常数和最大表观结合量分别为Kd2=7.18×10-3mg/mL和Qmax2=12.51 mg/g.结合底物的实验结果表明,利福平分子印迹聚合物微球对利福平呈现出了较高的吸附性能和选择识别特性,能较简便地用于利福平的分离和富集.  相似文献   

3.
建立了微球形氯嘧磺隆分子印迹聚合物的合成方法.优化了影响聚合物吸附性能的参数,对聚合物微球进行了性能表征.在氯嘧磺隆印迹微球的合成方法中,功能单体为甲基丙烯酸,交联剂为乙二醇二甲基丙烯酸酯,溶剂为乙腈,引发剂为偶氮二异丁腈,当其用量分别为0.25,1.5,5 mmol(物质的量比1:6:20)、30 mL和0.30 mmol时合成的分子印迹聚合物对氯嘧磺隆有最好的特异性吸附能力.运用Scatchard 方程测定了该聚合物的结合能力.结果表明,聚合物中具有两类亲和性吸附位点,高亲和性吸附位点的最大表现吸附量Qmax1为63.46 μmol/g,平衡常数Kd1为0.655 7 mmol/L;低亲和力吸附位点的最大表观吸附量Qmax2为437.085 μmol/g,平衡常数Kd2为11.00 mmol/L.聚合物微球在重复使用9次后吸附性能基本无下降.本制备方法具有无需研磨筛分即可得到分子印迹微球的特点,便于作为固相萃取柱和色谱柱的填料使用.  相似文献   

4.
以丙烯酰胺为功能单体,合成了对(S)-萘普生具有高手性选择性的分子印迹聚合物.通过紫外光谱分析了聚合物制备过程中(S)-萘普生与功能单体丙烯酰胺形成的复合物,并用Hyperchem软件模拟其结构.分子印迹聚合物对模板分子的结合量高于其对映异构体,手性分离因子α达1.87.Scatchard分析表明分子印迹聚合物在识别(S)-萘普生分子过程中存在2类结合位点,计算得到高亲和力的结合位点的离解常数Kd.1和最大表观结合常数Qmax.1分别为28.0μmol/L和52.94μmol/g,低亲和力的结合位点的离解常数Kd.2和最大表观结合常数Qmax,2分别为0.489mmol/l和0.122mmol/g.  相似文献   

5.
三唑醇分子烙印聚合物的吸附特性   总被引:5,自引:1,他引:4  
实验采用分子烙印技术合成了对农药三唑醇有特异性作用的分子烙印聚合物(molecularly im-printed polymer,MIP).通过平衡吸附实验,评价了其对三唑醇的亲和力和选择性.与非烙印聚合物相比,分子烙印聚合物对三唑醇表现了较强的亲和力;Scatchard分析表明,以甲基丙烯酸为功能单体,以三唑醇为模板的分子烙印聚合物,通过离子作用和氢键作用可形成两类结合位点.用多点结合模型计算两类不同结合位点的离解常数为Kd1=2.80×10-4mol/L,Kd2=9.71×10-3 mol/L.实验表明,该聚合物对三唑醇有高亲和力和选择性,为在生物样品中选择富集三唑醇提供了可能性.  相似文献   

6.
以手性药物左旋萘普生(S-naproxen)为模板分子,四乙烯基吡啶(4-VPy)为功能单体,采用表面印迹法,以介孔材料SBA-15为载体合成了能选择性识别S-naproxen的分子印迹聚合物微球.扫描电镜及孔结构分析结果表明,所合成的分子印迹聚合物微球具有粒径均匀、孔径分布窄、比表面积大等特点;同时扫描电镜、X射线衍射和红外光谱分析结果表明载体表面形成了分子印迹聚合物层,Scatchard分析表明分子印迹聚合物在自组装过程中存在两类结合位点,聚合物高亲和力和低亲和力结合位点的最大表观结合容量分别为Qmax1=2.504μmol/g,Qmax2=16.680μtmol/g;分子印迹聚合物的热力学研究表明,吸附过程可以自发进行.  相似文献   

7.
以邻苯二甲酸二丁酯(DBP)为模板分子、甲基丙烯酸(MAA)为功能单体、乙二醇二甲基丙烯酸酯(EGDMA)为交联剂、乙腈为溶剂,采用沉淀聚合法制备分子印迹聚合物(MIPs),并利用扫描电镜及红外吸收光谱法对MIPs进行表征,采用Scatchard和Langmuir模型进行分析。结果表明:(1)印迹聚合物对模板分子存在2类不同结合位点,一类结合位点的解离常数K_(d1)=0.053 g/L,最大表观结合量Q_(max1)=27.3 mg/g;另一类结合位点的解离常数K_(d2)=0.16 g/L,最大表观结合量Q_(max2)=42.8 mg/g。(2)吸附过程较好地满足Langmuir吸附方程,饱和吸附量为31.7 mg/g。  相似文献   

8.
阿特拉津分子印迹聚合物微球的制备及表征   总被引:1,自引:0,他引:1  
以阿特拉津(Atrazine)为模板分子,甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,采用沉淀聚合法制备了粒径约210nm的阿特拉津纳米分子印迹聚合物(MIPs)微球.采用紫外分光光度法确定了模板分子与功能单体的最佳物质的量比为1:4.Scatchard分析表明,分子印迹聚合物纳米微球存在两种不同的结合位点,最大表观吸附量(Qmax)和平衡离解常数(Kd)分别为Qmax1=38.08μg/g,Kd1=0.2489μg/L,Qmax2=310.33μg/g,Kd2=6.6269μg/L.此方法制备的分子印迹聚合物对阿特拉津具有良好的选择性吸附能力.  相似文献   

9.
以甲基丙烯酸为功能单体,环丙沙星为模板分子,采用悬浮聚合的方法制备了球形分子印迹聚合物,并用扫描电镜对聚合物进行了表征;通过平衡吸附法研究了聚合物对模板分子及其类似物的吸附行为和选择识别能力.结果表明,实验所研究的分子印迹聚合物,吸附4 h后基本接近最大吸附量,其中模板分子、MMA和交联剂物质的量比为1:6:20的MIPMs2最大表观吸附量为183.18 μmol/g, 印迹因子为1.58,效果最佳.吸附过程存在两类结合位点,一类为特异性印迹吸附,另一类为非特异性吸附;该分子印迹聚合物有很好的选择吸附性和再生性,可用于环丙沙星药物的分析和分离.  相似文献   

10.
以二溴荧光黄为印迹分子,丙烯酰胺为功能单体,季戊四醇三丙烯酸酯为交联剂,制备对二溴荧光黄有较好选择性的印迹聚合物.利用静态平衡结合法和Scatchard分析法研究此印迹聚合物的结合能力和选择性.结果表明,以丙烯酰胺为功能单体的印迹聚合物中形成两类不同的结合位点,计算离解常数分别为6.18×10-4mol/L和Kd2=5.73×10-3mol/L.对比二碘荧光黄和荧光素的结合特性,该印迹聚合物呈现较好的选择性.研究二溴荧光黄在溶液中和聚合物中荧光光谱的变化.  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 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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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