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1.
以马来酸酐为原料制备聚天冬氨酸,并对聚合反应的质量配比、聚合温度和聚合时间三个反应条件进行了优化实验,对最优条件下合成的PASP与其它阻垢剂进行了性能对比。结果表明:合成PASP的最佳条件是:原料质量配比为1:1.1,聚合温度为160℃,聚合时间为1h,阻垢率可以达到95%以上,生物降解性能达到70%。  相似文献   

2.
脂肪族高效减水剂的合成工艺   总被引:1,自引:0,他引:1  
以甲醛、丙酮和亚硫酸钠为主要原料合成了脂肪族羟基磺酸盐高效减水剂。研究了原料配比、亚硫酸钠浓度、聚合温度以及聚合时间对产物分散性能的影响,确定了合成脂肪族羟基磺酸盐高效减水剂的优化工艺条件。优化的工艺条件是:n(丙酮)∶n(甲醛)∶n(亚硫酸钠)=1∶2∶0.4,聚合温度是90℃,聚合时间是3h。在此工艺条件下,掺量为1%产物的净浆流动度为145 mm,减水率达到了11%,固含量达到了25%。  相似文献   

3.
讨论了以顺丁烯二酸酐和石油裂解副产C9馏分为原料,采用热聚合法合成造纸用含羧基石油树脂过程中原料配比、聚合温度、聚合时间、C9馏分的不同组成对产率及产品性能的影响。提出了最佳合成工艺条件为C9馏分与顺丁烯二酸酐的质量配比为100∶9 ̄100∶15,聚合温度为230 ̄260℃,聚合时间为4 ̄16h。  相似文献   

4.
介绍了对甲苯磺酸和硫酸氢钾混合催化剂合成柠檬酸三丁酯的研究。考察了催化剂配比、催化剂用量、原料配比、反应温度和反应时间等因素对合成反应的影响,确定了最佳反应条件:酸醇摩尔比为1:4.5,催化剂用量为3.0%,对甲苯磺酸和硫酸氢钾质量比为1:3,反应温度为140~150℃,反应时间为3h,柠檬酸三丁酯酯化率可达到96.9%。  相似文献   

5.
以壬基酚聚氧乙烯醚(TX-10)为原料,以P2O5为磷化剂,合成壬基酚聚氧乙烯醚磷酸酯。考察了P2O5的投料方式,原料配比,酯化时间,酯化温度对酯化率的影响,确定了最佳酯化条件:在40℃强烈搅拌下分批加入P2O5,配比为3.2/1(mol/mol),酯化温度75℃,酯化时间4.5h,在该条件下合成的产品酯化率为78.9%。同时研究了壬基酚聚氧乙烯醚磷酸酯的性能。  相似文献   

6.
以乳酸(LA)、乙醇酸(GA)为原料,在无催化剂、高真空条件下直接熔融缩聚合成聚乳酸-乙醇酸(PLGA)无规共聚物,对产物进行了GPC、FTIR、1H-NMR表征,并研究了反应时间、聚合温度、LA/GA投料比对PLGA分子质量的影响.结果表明:在所研究的聚合温度范围内,PLGA分子质量随聚合时间的延长先增大后减小;聚合温度越高,PLGA所能达到的最高分子质量越小,最佳聚合温度范围为160~170 ℃,最佳反应时间范围为57~69 h;在相同反应条件下,LA/GA投料比越小,PLGA分子质量越大.该研究为PLGA的合成提供一种安全、经济、有效的新途径.  相似文献   

7.
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   

8.
以二乙烯三胺与2-氯乙醇为主要原料合成五羟乙基二乙烯三胺,采用单因素试验和正交实验对原料配比及工艺条件进行优化,最佳配比为:二乙烯三胺与2-氯乙醇的摩尔比为1∶6.5;最佳工艺条件为:反应温度85℃,反应时间5 h,收率达到了98.76%,并用羟值测定、胺值测定、FT-IR、1H-NMR及ES-MS等方法对产物进行结构表征.  相似文献   

9.
松香改性油酸基咪唑啉季铵盐的缓蚀性能   总被引:1,自引:0,他引:1  
以不同配比的油酸和松香作为原料酸,在一定条件下与二乙烯三胺合成咪唑啉中间体,并用氯化苄进行季铵化得到松香改性油酸基咪唑啉季铵盐.利用红外光谱对产品的结构进行分析,并用静态质量损失法测定产物在盐酸介质中对Q235钢的缓蚀率.结果表明,合成高性能的咪唑啉季铵盐所用的最佳工艺条件为:原料酸中松香摩尔分数20%、二乙烯三胺与酸的摩尔比1.4~1.5、反应温度170~180℃、回流时间4h;当咪唑啉季铵盐作为缓蚀剂加入质量分数达到0.3%~0.4%时,可发挥其最佳缓蚀性能.  相似文献   

10.
赵迎春 《科学技术与工程》2013,13(16):4724-4726
以2,6-二甲基溴苯为原料,经氰基化,两步水解等反应合成了2,6-二甲基苯甲酸,并对氰基水解反应的工艺条件进行了优化。先将氰基在碱性条件下水解成酰胺,收率:100%;再在酸性条件下水解酰胺,得到最优的酰胺水解条件是:酰胺与65%硫酸的配比为1 g∶10 mL,水解温度110℃,水解时间12 h,收率达到:85%。  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

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