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1.
高磺化度SEPDM的制备及离聚体性能研究   总被引:6,自引:0,他引:6  
研究了磺化度大于0.5mol/kg的磺化三元乙丙橡胶的制备及离聚体的加工和力学性能,讨论了磺化反应的影响因素,得到了优化的横化反应条件:n(乙酸酐):n(浓硫酸)=1:1,5℃下反应30min。硬脂酸锌是高磺化度SPDMZn离聚体的有效增塑剂,其质量分数为10%-30%时,可显著改善离聚体的加工性能。  相似文献   

2.
研究了以不锈钢为电极、高氯酸为掺杂剂、水为溶剂,将苯胺(An)直接聚合成具有较好导电性能(电导率为6.67s·cm-1)和机械性能(抗张强度为0.34N·mm-2,断裂伸长率为12.6%)的聚苯胺(PAn)自支撑膜的电化学方法,并探讨了电化学聚合反应条件对PAn膜性能的影响,同时借助SEM、IR、ESR等手段表征了所得的聚合物膜。  相似文献   

3.
用溶液法制备顺酐化聚丙烯(MPP)及用熔融和溶液两种方法中和得到了顺酐化聚丙烯离聚体,并研究了它们的力学性能.结果表明:对于聚丙烯顺酐化,当顺丁烯二酸酐(MAH)占反应物的7.1%时,产物中MAH结合量为6.8%,利用率最高,达到95.8%.用溶液法中和得到的离聚体其拉伸强度比用熔融法得到的大,且拉伸强度随顺酐结合量的增大,先增大后减小,出现极大值,中和度达到125%时拉伸强度和冲击强度都达到最大值.一价金属离子离聚体的拉伸强度比二价金属离子离聚体的小,所有离聚体的拉伸强度及抗冲强度明显优于聚丙烯(PP).  相似文献   

4.
聚苯胺合成的中试放大研究   总被引:2,自引:0,他引:2  
为了促进导电聚苯胺(PAn)的产业化,采用工业品的苯胺、盐酸、过硫酸铵为原料,以自来水为溶剂,用化学法进行了PAn合成反应的逐级放大(一次最大投料总容积359L,苯胺一次最大投料量22500g)的中间试验研究。实验结果表明,在其最佳条件下,小试合成PAn的电导率都在34.00S·cm-1左右,最高可达38.46S·cm-1。逐级放大合成PAn的电导率,在100L总容积(苯胺一次投料7500g)以内都超过30.30S·cm-1。元素分析和红外光谱的研究表明,用工业品原料合成的PAn与用试剂级原料合成的PAn在化学组成和微观结构上基本相同。文章还分析了大投料量合成PAn电导率的影响因素,发现主要在于有效控制温度等反应基本条件和各组份的相对浓度,亦即在于完全重复小试合成的所有条件。  相似文献   

5.
本文对以浓硫酸和丙酸酐为磺化剂,在环己烷溶液中制备的增塑磺化聚苯乙烯(PSS-SA)离聚体的力学性能和形态结构进行了研究。结果表明,少量磺酸盐离子的引入有利于材料强度的提高。随着磺酸盐含量的增加,离聚体的拉伸强度增大,伸长率下降。不同金属反离子中和的PSSS离聚体的拉伸强度与金属离子半径及其价数有关。在离子含量大于或等于4.40×10-2摩尔分数(x)(以下同)的PSSS离聚体中,有离子簇聚集,离子簇直径为5~10nm。DOP在对PSSS离聚体基体增塑的同时,使离子簇的分布均匀化,而对离子簇尺寸影响不大  相似文献   

6.
聚苯胺的掺杂及其导电性能研究   总被引:5,自引:0,他引:5  
利用对甲基苯磺酸(TSA)和磺基水杨酸(SSA)对聚苯胺(PAn)进行了掺杂,研究了在掺杂过程中浓度、温度及时间对聚苯胺电导率的影响,并对掺杂态PAn在空气中电导率与温度的关系进行了研究,结果表明TSA和SSA掺杂的PAn在研究的温度范围内电导率均随温度的提高而增加。  相似文献   

7.
聚2,5-二甲氧基苯胺(P25DMAn)薄膜电极用电聚合的方法制得.采用循环伏安法研究了酸性溶液中抗坏血酸(AH2)在P25DMAn薄膜电极上的电催化氧化.该薄膜电极对抗坏血酸的氧化有很好的电催化活性.讨论了不同种类负离子存在的情况下制成的薄膜对AH2氧化的催化特性的影响.光电子能谱图所得的结果也证明了P25DMAn薄膜电极上有AH2反应的物种产生.用旋转圆盘电极研究了催化过程动力学.  相似文献   

8.
聚丙烯离聚体的制备及其力学性能   总被引:1,自引:0,他引:1  
用溶液法制备顺酐化聚丙烯(MPP)及用熔融和溶液两种方法中和得到了顺酐化聚丙烯离聚体,并研究了它们的力学性能。结果表明:对于聚丙烯顺酐化,当顺丁烯二酸酐(MAH)占反应物的7.1%时,产物中MAH结合量为6.8%,利用率最高,达到95.8%。用溶液法中和得到的离聚体其拉伸强度比用熔融法得到的大,且拉伸强度随顺酐结合量的增大,先增大后减小,出现极大值,中和度达到125%时拉伸强度和冲击的强度都达到最  相似文献   

9.
合成了低密度聚乙烯接枝马来酸镧(LDPE-g-MALa)离聚物,并对该离聚物进行了确证.实验结果表明:在LDPE-g-MALa的IR谱上于1605cm-1处出现了羧酸盐的C=O伸缩振动峰,同时WAXD谱上新出现的2θ=16.70°,13.80°两个强衍射峰,也证明确有离子微区的存在.DSC研究说明该接技产物结晶度降低,结晶速率加快.TGA图则说明离子化可以提高聚合物的稳定性.  相似文献   

10.
聚乙烯接枝马来酸锌离聚体溶液性质的研究   总被引:1,自引:0,他引:1  
探索了溶解PE-g-MAZn离聚体的溶剂体系,并研究其溶液粘度行为,发现该离聚体的粘浓关系与极性聚合物PE-g-MAH相似,即比浓粘度ηsp/c随浓度的增大分为极稀溶液区和稀溶液区2个区间,2个区间内的粘浓关系都呈线性,但斜率不同,其交会点对应的学我为2.0g/L。该离聚体的粘温关系随温度的上升出现起伏。  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.
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   

13.
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   

14.
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   

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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
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   

20.
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   

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