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1.
以己二胺、丙烯酸甲酯为原料,甲醇钠为催化剂,吩噻嗪为阻聚剂,在甲醇介质中通过Michael加成反应室内合成了己二胺四丙酸甲酯(0.5G支化物),考察了阻聚剂种类对产物收率的影响。再以0.5G支化物为原料与乙二胺通过酰胺化缩合反应合成了己二胺四丙酰胺二胺(1.0G支化物),并对其合成条件进行了研究。结果表明:1.0G支化物的最佳合成条件为n(己二胺)∶n(0.5G)=4.5∶1,反应温度为40℃,反应时间为24 h,收率为92.87%。同时借助IR光谱及ESI-MS对1.0G产物进行了官能团验证和结构表征,研究并归属了该化合物主要特征碎片离子的裂解途径。  相似文献   

2.
稠油油溶性降黏剂ASAM/C/O的合成与评价   总被引:1,自引:0,他引:1  
分析了造成稠油高黏的原因及降黏剂的降黏机理,对降黏剂的分子结构进行设计.先以丙烯酸(A)、苯乙烯(S)、丙烯酰胺(AM)为原料合成了中间产物——三元共聚物ASAM,然后以ASAM、多元醇、长链烷基酸为原料通过两步酯化反应合成了一种稠油油溶性降黏剂ASAM/C/O.通过正交实验确定出中间产物ASAM的最佳合成条件:单体质量比m(丙烯酸)∶m(苯乙烯)∶m(丙烯酰胺)为6∶3∶2,引发剂质量分数1.3%,反应时间为6 h.降黏剂ASAM/C/O的最佳合成条件∶m(ASAM)∶m(C)∶m(O)取6∶2∶1.5,长链烷基酸的碳链长度取18,反应温度在110~120℃之间,反应时间为6 h左右.降黏剂ASAM/C/O具有较好的降黏效果;降黏率与温度有关,随温度降低,降黏率升高;加剂处理后稠油体系的活化能大幅度降低,说明体系内的结构强度减弱.  相似文献   

3.
根据原油防蜡剂的作用机制,通过分子设计,以甲基丙烯酸十八酯(O),马来酸酐(M),苯乙烯(S)作为为共聚反应的单体,过氧化苯甲酰(BPO)作为引发剂,甲苯为溶剂,采用溶液聚合的方式合成三元共聚物OMS,考察其最佳合成条件。结果表明:在n(O)∶n(M)∶n(S)=9∶1∶1、反应温度为90℃,w(BPO)=1.2%、反应时间为8 h的条件下,合成的防蜡剂对新疆油田的油井防蜡率可以达到50%;OMS与OP型表面活性剂复配后,防蜡效果更好,且防蜡剂具有一定的降黏降凝作用。  相似文献   

4.
根据原油防蜡剂的作用机制,通过分子设计,以甲基丙烯酸十八酯(O),马来酸酐(M),苯乙烯(S)作为为共聚反应的单体,过氧化苯甲酰(BPO)作为引发剂,甲苯为溶剂,采用溶液聚合的方式合成三元共聚物OMS,考察其最佳合成条件。结果表明:在n(O)∶n(M)∶n(S)=9∶1∶1、反应温度为90℃,w(BPO)=1.2%、反应时间为8 h的条件下,合成的防蜡剂对新疆油田的油井防蜡率可以达到50%;OMS与OP型表面活性剂复配后,防蜡效果更好,且防蜡剂具有一定的降黏降凝作用。  相似文献   

5.
以自制的活性大单体聚乙二醇单甲醚丙烯酸酯(MPEGAA)、丙烯酸(AA)和丙烯酰胺(AM)为原料,在水溶液中共聚合成了酰胺型MPEGAA-AA-AM聚羧酸高效减水剂。重点考察了各单体的物质的量比、引发剂(APS)用量、聚合温度和聚合时间等合成工艺条件对酰胺型MPEGAA-AA-AM聚羧酸高效减水剂的影响。结果表明:最佳的高效减水剂的合成条件是:n(MPEGAA)∶n(AA)∶n(AM)=1.0∶1.5∶1.0,引发剂APS质量分数为单体总质量的5%,聚合温度和反应时间分别为85℃和5 h。在该条件下合成的酰胺型MPEGAA-AA-AM聚羧酸高效减水剂,90 min后流动度损失率仅为2%。  相似文献   

6.
左旋β蒎烯选择性氧化合成右旋诺蒎酮的研究   总被引:2,自引:0,他引:2  
以(-)β蒎烯为原料,经选择性氧化合成(+)诺蒎酮,分析了在不同氧化剂及溶剂体系下β蒎烯的氧化行为。研究了β蒎烯与高锰酸钾摩尔比、硫酸与高锰酸钾摩尔比、溶剂类型、反应温度、反应时间等因素对β蒎烯氧化转化率和诺蒎酮产物选择性的影响。结果表明,左旋β蒎烯选择性氧化合成右旋诺蒎酮适宜的氧化工艺条件:β蒎烯与高锰酸钾摩尔比为1∶3,硫酸与高锰酸钾摩尔比0.054∶1,以丙酮为溶剂,反应温度为15~25 ℃,反应时间为5 h。此条件下β蒎烯转化率为94.15 %,诺蒎酮选择性为89.19 %,诺蒎酮得率为83.97 %,纯度为95.29 %,比旋光度为[α]18D+33.86°(c 1.01, CHCl3)。另外,采用IR、GC-MS、1H NMR和13C NMR等对诺蒎酮结构进行了表征。  相似文献   

7.
Sol-Gel固定磷钨酸催化合成乙酸丁酯   总被引:4,自引:0,他引:4  
制备了正硅酸乙酯凝胶(Sol-Gel)固定磷钨酸催化剂,催化合成乙酸丁酯.实验表明Sol-Gel与磷钨酸的质量比为15∶1时催化性能最高,在催化剂用量为总反应物质量的5%、酸醇比为1.5∶1、反应温度为105°C、反应时间3.5h的条件下,酯产率可达87%以上.催化剂易与产物分离,重复使用8次催化效果仍然较好.  相似文献   

8.
以MA和AMPS为原料,以过硫酸铵为引发剂合成了ESA/AMPS共聚物.通过静态阻垢实验,考察了各实验条件对ESA/AMPS共聚物阻碳酸钙垢、磷酸钙垢的阻垢率的影响.得出最佳合成工艺条件为单体配比m(MA)∶m(AMPS)=3∶1,引发剂用量质量分数4%,聚合时间3h,聚合反应温度85~90℃.阻垢剂投药量约5mg/L时,阻垢效果最好.  相似文献   

9.
月桂酰二乙醇胺的合成及性能研究   总被引:2,自引:0,他引:2  
烷醇酰胺类表面活性剂是非离子表面活性剂中重要的品种之一.用均匀试验设计法,考察了月桂酰二乙醇胺的改进一步法合成条件,并对产物作结构分析和发泡性能测定.结果表明,月桂酰二乙醇胺的最优合成条件为n(月桂酸)∶n(二乙醇胺)=1∶2.2,反应温度159℃,反应时间3.2 h,泡沫高度为183.3 mm.  相似文献   

10.
为有效提高胶黏剂的胶合强度,用丙烯酸酯接枝大豆蛋白进行乳液聚合反应,得到丙烯酸酯改性大豆蛋白胶黏剂;采用FT-IR表征产物,考察丙烯酸酯接枝大豆蛋白胶黏剂的固含量、黏度;通过正交试验确定胶黏剂制备、胶合板样板压制的最佳工艺条件.结果表明:改性大豆蛋白胶黏剂固含量为24.0%~27.3%,耐水性明显高于普通大豆蛋白胶;改性胶黏剂最佳制备工艺条件为p H在8.0~8.5,m(大豆蛋白)∶m(水)∶m(马来酸酐)∶m(引发剂)为80∶150∶3∶10,在该配比下胶合强度最好,胶合板的耐水性提高,胶合强度在0.70 MPa以上,均符合国家标准GB/T 9846—2004Ⅱ类胶合板要求;压制胶合板样板的最佳工艺条件为温度120℃、压强1 MPa、压板时间10 min,胶合板性能最佳,胶合强度达到1.12 MPa.  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.
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   

15.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
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   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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