共查询到20条相似文献,搜索用时 93 毫秒
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以衣康酸(IA)、马来酸(MA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为单体,以过硫酸铵为引发剂,以水为溶剂,通过自由基聚合合成了一种新型的三元共聚物,探讨了单体配比、聚合温度、引发剂用量、聚合时间等合成条件对阻垢性能的影响,确定了最佳的合成条件为:单体配比n(IA)∶n(MA)∶n(AMPS)=1∶1∶1,聚合温度80℃,引发剂占单体质量分数的5%,聚合时间2h;用红外分光光度仪分析证明得到了预期的产物结构,并测定了产物的特性黏度和固含量。通过静态法对三元共聚物的阻垢性能进行评价,在加剂量为50mg/L时阻碳酸钙率最佳可达93.6%,是一种性能优异的阻垢剂。 相似文献
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AA/HPA/SVS三元共聚物阻垢剂的合成及其性能研究 总被引:2,自引:1,他引:1
以丙烯酸(AA),丙烯酸羟丙酯(HPA)和乙烯基磺酸钠(SVS)为单体,过硫酸铵为引发剂,异丙醇为链转移剂,在水相中进行自由基聚合反应,合成了AA/HPA/SVS水溶性三元共聚物阻垢剂.系统考察了聚合工艺条件对该共聚物阻垢效果的影响,并对其阻垢分散性能进行了初步评价.结果表明,n(AA):n(HPA):n(SVS)为3:1:1,引发剂用量为14%,链转移剂用量为10%,反应温度为90℃,反应时间为2.5 h时,合成的共聚物阻垢性能最佳,在用量为16 mg·L-1时对碳酸钙和磷酸钙的阻垢率均能达到90%以上,并且具有较好的钙容忍度和分散氧化铁性能. 相似文献
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以水为溶剂,采用可逆加成断裂自由基聚合(RAFT)方法,合成了不同相对分子质量的丙烯酸与2-丙烯酰胺-2-甲基丙磺酸的共聚物(PAA-PAMPS),考察了PAA-PAMPS对碳酸钙、磷酸钙垢的阻垢性能.结果表明,同样条件下,用RAFT法合成的PAA-PAMPS共聚物对碳酸钙垢、磷酸钙垢的阻垢效果明显优于不可控自由基聚合合成的PAA-PAMPS样对2者的阻垢效果,尤其是对磷酸钙具有明显的阻垢效果,当Mn≈5 000、n(AA):n(AMPS)=9:1的PAA-PAMPS,其用量为8 mg·L-1时对磷酸钙的阻垢率达90%以上. 相似文献
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以马来酸酐(MA)、丙烯酸(AA)、聚丙烯(PP)单体自由聚合合成阻垢剂,研究了引发剂用量、反应物摩尔比、反应时间、反应温度对阻垢剂性能的影响.结果表明,当MA与AA摩尔比为7~8,单体PP用量为10%,引发剂用量为8%~12%时,在80 ℃时反应6~7 h合成的共聚物阻垢性能最好,阻垢率可以达到95%. 相似文献
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在工业生产中,冷却水循环系统的结垢会导致生产效率降低、生产成本增加以及生产不能正常进行,而加入阻垢剂是解决这一难题的有效、经济、简便的方法。因此,以马来酸(MA)、丙烯酸甲酯(MAC)、丙烯酸(AA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为单体,水为溶剂,过硫酸钾作为引发剂合成了一种新型四元共聚物阻垢剂。研究了不同聚合条件下生成共聚物对碳酸钙阻垢性能的影响,确定了最佳合成条件。结果表明,在单体摩尔n(MA)∶n(AA)∶n(AMPS)∶n(MAC)=8∶5∶3∶4,在引发剂质量为单体总质量的7.5%,反应温度85℃,反应时间3h条件下,共聚物对碳酸钙阻垢效率达94.5%以上。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%. 相似文献
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醋酸纤维素取代基分布与性质的关系 总被引:9,自引:0,他引:9
分析了以吡啶为溶剂的醋酸纤维素的13C-NMR核磁共振谱,得出了三种不同位置羟基的取代度。结合X—射线和DSC分析,初步说明具有相同取代度但未经水解和经过水解的醋酸纤维素(CA) 性质上的差异是由于三个羟基上的取代度分布不同及消晶程度差异所致。 相似文献