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1.
以莰烯、乙二醇、甲基丙烯酸甲酯为原料,经过醚化和酯交换反应合成了光固化涂料用活性稀释剂甲基丙烯酸异冰片基氧乙基酯(IBOEMA),采用GC-MS、IR等分析手段对合成产物的结构进行了分析测定.在莰烯与乙二醇的醚化过程中,以A-15作醚化催化剂,探讨了A-15用量、乙二醇与莰烯的物质量之比、反应温度、反应时间等对异冰片基羟乙基醚得率的影响.采用正交试验确定了异冰片基羟乙基醚的适宜合成条件:催化剂A-15的用量为6.0%,反应温度90℃,反应时间9h,乙二醇与莰烯的物质量之比为3.5∶1.0.在此条件下,莰烯转化率、反应选择性及产物得率分别达79%、93%和74%以上.在异冰片基羟乙基醚酯交换合成IBOEMA过程中,以环己烷为溶剂,反应在回流状态下进行,探讨了催化剂种类及用量、异冰片基羟乙基醚与甲基丙烯酸甲酯物质的量之比、反应时间、阻聚剂的种类和用量等对IBOEMA得率的影响.通过正交试验确定了异冰片基羟乙基醚与甲基丙烯酸甲酯酯交换反应的适宜工艺条件:以环己烷为溶剂进行回流反应,环己烷与异冰片基羟乙基醚物质的量之比为37∶1,甲基丙烯酸甲酯与异冰片基羟乙基醚的物质量之比为1.25∶1.00,催化剂KOH的用量为3%,反应时间8h,吩噻嗪用量为1%.在此条件下,异冰片基羟乙基醚的转化率、反应选择性及产物得率分别达91%、93%和85%以上.  相似文献   

2.
以莰烯和烯丙醇为原料,研究了烯丙基异冰片基醚的绿色合成工艺,探讨了催化剂种类及用量、反应温度、反应时间,以及烯丙醇与莰烯物质的量之比对莰烯醚化反应选择性及烯丙基异冰片基醚产物得率的影响。采用正交试验方法确定了烯丙基异冰片基醚的最适工艺条件:A-15型阳离子树脂为催化剂,催化剂用量为烯丙醇和莰烯原料总质量的5%,烯丙醇与莰烯物质的量之比为1.5∶1,反应温度75℃,反应时间7 h。在此条件下工业莰烯转化率为85.5%,反应选择性为97.5%,烯丙基异冰片基醚得率为83.4%。最后采用GC-MS、IR等分析技术对合成所得产物的结构进行了分析测定。  相似文献   

3.
甲基丙烯酸十八酯的合成   总被引:6,自引:1,他引:5  
研究了甲基丙烯酸和十八醇直接酯化合成甲基丙烯酸十八酯的工艺条件,主要探讨了甲基丙烯酸与十八醇摩尔比、催化剂和阻聚剂的用量、反应温度及反应时间对酯化反应的影响,得出了合成的最佳条件:甲基丙烯酸与十八醇摩尔比为2:1,对甲苯磺酸的质量分数为1.2%,对苯二酚的质量分数为0.7%,145℃反应4h,互化产率可达98%,酯化产物经熔点、元素分析及红外光谱测定,证明所得产物为甲基丙烯酸十八酯。  相似文献   

4.
甲基丙烯酸十六酯的合成及结构表征   总被引:3,自引:0,他引:3  
研究了以α-甲基丙烯酸和十六醇为原料采用直接酯化法合成α-甲基丙烯酸十六酯的工艺条件,主要探讨了α-甲基丙烯酸与十六醇摩尔比、催化剂和阻聚剂的用量以及反应时间对酯化反应的影响,得出了合成的最佳条件:α-甲基丙烯酸与十六醇的摩尔比为1.2:1,对甲苯磺酸的质量分数为1.4%,对苯二酚的质量分数为0.4%,反应温度为110~120℃,反应时间为5h,酯化产率可达到95%以上.酯化产物经薄层色谱分析及红外光谱、核磁共振谱测定,证明所得产物为α-甲基丙烯酸十六酯.  相似文献   

5.
MoO3/ZrO2催化合成乙酸异龙脑酯   总被引:6,自引:0,他引:6  
采用自制固体超强酸MoO3/ZrO2为催化剂,通过改变投料比、催化剂焙烧温度和用量,以及反应温度和反应时间等条件,研究了莰烯与乙酸加成制备乙酸异龙脑酯的适宜工艺条件。结果表明:酯化反应适宜的工艺条件为:莰烯与乙酸摩尔比1∶1.5,反应温度80℃,反应时间8 h,催化剂焙烧温度为700℃,催化剂质量分数为4%。在上述条件下,乙酸异龙脑酯得率为74.7%。  相似文献   

6.
甲基丙烯酸十四酯的合成及表征   总被引:5,自引:1,他引:5  
研究了甲基丙烯酸和十四醇直接酯化合成甲基丙烯酸十四酯的条件,主要探讨了甲基丙烯酸与十四醇摩尔比,催化剂和阻聚剂的用量及反应时间对酯化反应的影响,得出了合成的最佳条件:甲基丙烯酸与十四醇的摩尔比为1.1:1,对甲苯磺酸的质量分数为1.4%,对苯二酚的质量分数为0.9%,反应温度为110-120℃,反应时间为5h,酯化产率可达到99%.酯化产物经薄层色谱分析及红外光谱,核磁共振谱等进行了表征.  相似文献   

7.
以莰烯和甲基丙烯酸为原料,强酸性阳离子交换树脂为催化剂合成甲基丙烯酸异冰片酯. 考察几种强酸性阳离子交换树脂(CT800,CT275,CT269和UPR65)的催化活性,并从催化剂的结构对实验结果进行分析. 结果表明,CT800阳离子交换树脂的离子交换容量和比表面积最大,整体催化性能最佳. 在最佳工艺条件下(反应温度47℃,搅拌速率500r·min-1,烯酸比1∶0.8,反应时间4h,催化剂用量为反应物总质量的10%),甲基丙烯酸异冰片酯的收率可达83.15%,主反应选择性为97.95%. CT800阳离子交换树脂催化剂稳定性高,经多次重复使用,催化活性未见明显下降,且易于再生.  相似文献   

8.
甲氧基聚乙二醇甲基丙烯酸酯大单体的制备   总被引:2,自引:1,他引:1  
以400,600,2000 3种分子质量的甲氧基聚乙二醇(MPEG)和过量甲基丙烯酸(MAA)为主要原料,通过酯化反应制备了聚羧酸盐减水剂所用大单体甲氧基聚乙二醇甲基丙烯酸酯(MPEGMA).研究了酯化反应时间、酸醇比、酯化温度、催化剂、阻聚剂对酯化反应的影响;结果表明:酯化反应时间以7~8 h较为合理,MAA与MPEG物质的量之比对酯化率的影响最为显著,其次是反应温度,催化剂用量对低分子量MPEG的酯化反应影响较小,但随着MPEG分子量增大催化剂的影响变得显著.MPEG400的最佳酯化条件为:nMAA∶nMPEG为2∶1,反应温度100℃,催化剂为总质量的2%,阻聚剂为甲基丙烯酸质量的0.5%;MPEG600的最佳酯化条件为:nMAA∶nMPEG为2.5∶1,反应温度110℃,催化剂用量为总质量的4%,阻聚剂为甲基丙烯酸质量的0.5%;MPEG2000的最佳酯化条件为:nMAA∶nMPEG为5∶1,反应温度110℃,催化剂为总质量的6%,阻聚剂为甲基丙烯酸质量的0.5%.红外图谱表明3种分子量的MPEG与MAA反应后均生成了酯化大单体.  相似文献   

9.
以1,6-己二醇、丙烯酸为原料,对甲苯磺酸与亚磷酸为催化剂,环己烷为带水剂,CuSO4/NaHSO4为复合阻聚剂,采用直接酯化法合成1,6-己二醇二丙烯酸酯.对合成产物进行了酸值测定和FT-IR分析.探讨了催化剂、带水剂、阻聚剂、反应时间和温度以及酸醇比(丙烯酸/1,6-己二醇,物质的量之比)对酯化反应的影响.研究结果表明,最佳的酯化反应条件为:丙烯酸/1,6-己二醇为2.5,催化剂用量(占原料总质量,%)为1.5%,阻聚剂用量(占丙烯酸用量,%)为8.5%,带水剂用量(占原料总质量,%)为65%,反应时间为90 min,反应温度为80~90℃.在此条件下,产物为无色透明油状液体,收率可达93.25%.  相似文献   

10.
采用甲基丙烯酸甲酯与二缩三乙二醇进行酯交换的方法合成了二缩三乙二醇双甲基丙烯酸酯,考察了反应时间、反应物配比、催化剂及阻聚剂的种类和用量对收率的影响,并经高效液相色谱对反应产物进行定量分析.结果表明:酯交换法较酯化法可以显著地缩短反应时间;在酯交换反应中,反应物质的量比和催化剂用量是较为重要的影响因素.当酯醇物质的量比为6∶1,反应时间为4 h,催化剂和阻聚剂质量分别为原料质量的1.5%和0.15%时,二缩三乙二醇双甲基丙烯酸酯的收率可达95%以上.  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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