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1.
以2,4-二异氰酸甲苯,丙烯酸β-羟丙酯、正戊醇,正壬醇为原料,合成了2种不饱和丙烯酸化异氰酸酯单体(AAT,NAT),并用自动记录膨胀计测定了2种单体在2-羟基-2-甲基-1-苯基-丙-1-酮(Darocur1173),α,α-二甲氧基苯乙酮(DEAP),α,α-二甲氧基-α-苯基苯乙酮(DMPA)为光引发剂时的聚合速率。结果表明,单体的活性NAT>AAT,引发剂的引发活性为DEAP≥DMPA>Darocur1173,单体的聚合速率受溶剂影响。  相似文献   

2.
环状碘Weng盐光引发体系的研究   总被引:1,自引:0,他引:1  
合成了3种环状碘Weng盐,表征了它们的紫外吸收光谱特征,研究了碘Weng盐-铜-胺三元引发体系引发丙烯酸β-羟乙酯(HEA)-三羟甲基丙烷三丙烯酸酯(TMPTA)的自由基聚合,结果表明,向酮-胺体系中加入环状碘Weng盐可以大大加快聚合速度,根据实验结果,推出了光引发机理。  相似文献   

3.
环状碘鎓盐光引发体系的研究   总被引:1,自引:0,他引:1  
合成了3种环状碘鎓盐,表征了它们的紫外吸收光谱特征,研究了碘盐-酮-胺三元引发体系引发丙烯酸?-羟乙酯(HEA)-三羟甲基丙烷三丙烯酸酯(TMPTA)的自由基聚合,结果表明,向酮-胺体系中加入环状碘盐可大大加快聚合速度。根据实验结果,推出了光引发机理。  相似文献   

4.
丙烯酸及丙烯酸酯光固化反应过程的研究   总被引:5,自引:0,他引:5  
利用红外光谱跟踪体系光固化反应过程中的双键转化,比较了不同光引发剂的引发活性,探讨了光固化反应的各种影响因素和反应规律。发现光引发剂a,a-二甲氧基-a-苯基苯乙酮和a-羟基-a,a-亚戊基苯乙酮的活性显著大于安息香乙醚;升高温度、增大入射光强和在氮气气氛中反应,可有效提高光固化反应速度和涂漠的最终转化率。  相似文献   

5.
以自然光为光源,茂铁型阳离子光引发剂二茂铁四氟硼酸盐([CpFeCp]BF4)可有效地引发脂环族环氧光敏体系的光固化。光解研究发现,其由d-d跃迁产生的在620nm处吸收峰为可见光引发的有效吸收峰。通过考察[CpFeCp]BF4/环氧化合物光固化体系的固化活性及影响因素,发现其与脂环族环氧化合物ERL-4221组成的光敏体系的光固化速度随着自然光照强度的增强和固化温度的提高,固化速度随之提高。  相似文献   

6.
偶氮二异丁脒盐酸盐引发丙烯酰胺聚合的研究   总被引:2,自引:0,他引:2  
李玉江 《山东科学》1996,9(2):43-45
本文研究了偶氮二异丁脒盐酸盐引发丙烯酰胺聚合的反应动力学,得出聚合速率方程式为RP-KP(AIBA)^0.5(AM),测定了聚合表现活化能,并研究了聚合条件对产物分子量及其分布的影响,利用该引发-聚合体系,获得了相对分子质量上千万的超高分子量聚丙烯酰胺。  相似文献   

7.
本报道合成八个有机硅化合物,均可用作甲基丙烯酸甲酯的基团转移聚合(Group Transfer Polymerization GTP)引发剂,在相同单体、催化剂、溶剂配比和聚合条件下,进行反应,所得产物用凝胶渗透色谱(GPC)作了分子量及分量分布的表征,引发剂的结构和活性对产物的分子量和分布宽度均有显着影响,所用引发剂中以1-甲氧基-1(三甲硅氧基)-2-甲基-1-丙烯和双(乙氧基)-3-甲氧…  相似文献   

8.
铁-芳烃配合物引发环氧化合物阳离子光聚合反应机理   总被引:4,自引:0,他引:4  
研究了铁-芳烃配合物引发环氧化合物阳离子光聚合反机理,讨论了反庆条件对聚合反应的影响。结果表明,聚合反应为n+1级反应,n为环氧化物与引发剂形成的配合物的配位数。  相似文献   

9.
以4,4‘-偶氮二[4-氰基戊酰(对-二甲基氨基)苯胺](ACPDA)为引发剂,先热分解引发甲基丙烯酸甲酯聚合,得到含有4,4-二甲胺基端基的预聚物,它与BPO组成氧化还原体系引发丙烯酰胺聚合后,得到聚甲基丙烯酸甲酯-丙烯酰胺嵌段共聚物,研究了反应组成及反应条件对嵌段共聚合反应的影响,结果表明在嵌段共聚物中,丙烯酰胺聚合物的含量随反应组成及反应条件而异,其含量可达50%以上。  相似文献   

10.
本文采用水相沉淀聚合法研究了二过碘酸合银(Ⅲ)-尿素氧化还原引发体系在碱性介质中引发丙烯腈聚合反应,测得了各种因素对聚合反应速率、聚合物分子量的影响,并探讨了引发机理。  相似文献   

11.
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   

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

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
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.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
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   

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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