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1.
四(4-磺酸基苯基)卟啉在甲壳素膜上的聚集行为研究   总被引:1,自引:0,他引:1  
利用紫外-可见光光谱仪与共振光散射(RLS)技术研究了在控制条件下的四(4-磺酸基苯基)卟啉(TPPS)在甲壳素膜上的聚集行为.研究发现TPPS在甲壳素膜上的聚集行为强烈地依靠溶液的pH值,在pH值小于4时,TPPS在甲壳素膜上以J-型与H-型聚集体共存的形式聚集,而溶液pH值较高时,TPPS则只能以H-型聚集体的形式聚集于甲壳素膜上.  相似文献   

2.
Meso-四-(4-磺基苯基)-卟啉光度法测定铅的研究   总被引:5,自引:0,他引:5  
研究了 meso-四-(4-磺基苯基)-卟啉(TPPS4)与铅的显色反应,在pH=11~13.5的碱性介质中,TPPS4与铅生成1 : 1络合物,λmax=470nm,ε=3.28×105L·mol-1·cm-1,铅的含量在0~10μg/25ml内符合比尔定律,方法用于食品和水样中铅的测定,结果满意.  相似文献   

3.
本文采用表面活性剂十六烷基三甲基溴化铵(CTAB)和嵌段共聚物聚乙二醇-b-聚4-乙烯基吡啶(PEG-b-P4VP)分别与5,10,15,20-四-(4-对磺酸基苯基)-锌卟啉(Zn TPPS)进行功能组装,形成以静电相互作用结合的CTAB/Zn TPPS复合体,以配位作用结合的PEG-bP4VP/Zn TPPS复合体,对复合体进行了紫外-可见光谱、荧光发射光谱、透射电子显微镜以及动态光散射表征。研究结果表明:静电作用和配位作用均能增强Zn TPPS的光学稳定性,但CTAB和PEG-b-P4VP浓度对其稳定性影响因素不同。在CTAB/Zn TPPS复合体中,随着CTAB浓度的降低,Zn TPPS的光学稳定性增加;而在PEG-b-P4VP/Zn TPPS复合体中,随着聚合物浓度的增强,Zn TPPS的光学稳定性逐渐增强。相比而言,配位作用在提高金属卟啉的光学稳定性方面发挥着更大的作用。  相似文献   

4.
以吡咯、苯甲醛为主要原料,合成得到四苯基卟啉;将其经硝化、还原、磺化反应处理,又分别得到5-(4-硝基苯基)-10,15,20-三苯基卟啉、5-(4-氨基苯基)-10,15,20-三苯基卟啉、5-(4-氨基苯基)-10,15,20-三(4-磺酸钠苯基)卟啉3种不同取代四苯基卟啉化合物,借助元素分析、红外光谱和核磁共振氢谱等手段对所合成的4种化合物进行了表征.采用紫外-可见光谱法、荧光光谱法以及循环伏安法对4种化合物的光谱性质和电化学性质进行了探究,并讨论了不同取代基的影响.  相似文献   

5.
探索氧化锌固载四(4-羟基)苯基锰卟啉的催化性能.用混合溶剂法直接合成四(4-羟基)苯基卟啉(H2 THPP),采用研磨法合成四(4-羟基)苯基锰卟啉[Mn(Ⅲ)THPP].将Mn(Ⅲ)THPP固载到新生成的氢氧化锌沉淀上,经烘焙制得氧化锌固载四(4-羟基)苯基锰卟啉催化剂.用紫外和红外光谱对它进行表征.研究固载催化剂...  相似文献   

6.
四(对甲氧基苯基)卟啉钴的合成及表征   总被引:1,自引:1,他引:0  
以对甲氧基苯甲醛与吡咯为原料、丙酸为溶剂、氯乙酸为催化剂,合成四(对甲氧基苯基)卟啉及其钴配合物,用元素分析、紫外-可见光谱、红外光谱、1H核磁共振对化合物进行表征.结果表明,所合成的四(对甲氧基苯基)卟啉及四(对甲氧基苯基)卟啉钴配合物的结构与设计的结构相符;该配体及配合物的荧光光谱数据表明,相对荧光强度是四(对甲氧基苯基)卟啉四(对甲氧基苯基)卟啉钴四苯基卟啉.  相似文献   

7.
以非水溶性卟啉为原料合成水溶性卟啉meso-四(4-氯-3-磺酸钠苯基)卟啉,氯仿作溶剂,氯磺酸作为磺化试剂,与meso-四(4-氯苯基)卟啉反应,并确定其最佳反应条件为n(卟啉):n(氯磺酸)=1.33:29.80,氯仿15 mL,温度60 ℃,反应时间2 h.该法较传统磺化方法反应温度低60~80 ℃且易于控制,不产生粘稠状的副产物,产物易于分离纯化,产率达11.4 %.  相似文献   

8.
乙酸乙酯键联卟啉的合成与表征   总被引:1,自引:0,他引:1  
从5,10,15,20-四苯基卟啉合成5-(p-β-乙酸乙酯基氨基苯基)-10,15,20-三苯基卟啉:5,10,15,20-四苯基卟啉(A)与发烟硝酸反应得到5-(对-硝基苯基)-10,15,20-三苯基卟啉(B),产率48.7%;B与二氯化锡进行还原反应得到5-(对-氨基苯基)-10,15,20-三苯基卟啉(C),产率72.0%;C在无水碳酸钾和无水碘化钾催化下与氯乙酸乙酯进行亲核取代反应得到5-(p-β-乙酸乙酯基氨基苯基)-10,15,20-三苯基卟啉(D),产率8.5%。该方法的反应条件温和,合成路线短,纯化方法简单。  相似文献   

9.
以N,N 二甲基甲酰胺或二甲基亚砜为溶剂,在无水硫酸镁存在下,将CO2通入吡咯与苯甲醛混合液中反应,可以直接合成不含四苯基二氢卟啉(简称TPC)的四苯基卟啉(简称TPPH2)。  相似文献   

10.
以1-溴-2,3,4,6-O-乙酰-D-葡萄糖(1)或氯乙醇分别与5-(对-氨基苯基)-10,15,20-三苯基卟啉(2)反应,制备5-(对-(-D- 葡萄糖氨基苯基)-10,15,20-三苯基卟啉(3)或5-(对-羟乙基氨基苯基)-10,15,20-三苯基卟啉(4).该方法的反应条件温和,合成路线短,纯化方法简单.  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.
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   

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

15.
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   

16.
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   

17.
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   

18.
19.
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   

20.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

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