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91.
In the process of oilfield development, salt tolerance is an important property for enhanced oil‐recovery (EOR) chemicals. In this study, we synthesized two acrylamide‐based sulfobetaine copolymers containing 2‐hydroxy‐3‐[(3‐methacrylamidopropyl)dimethylammonio]propane sulfonate (SHPP) or 3‐(4‐acry‐loyl‐1‐methyl‐piperazinio)‐2‐hydroxypropane sulfonate (SHMP). The interactions between these two copolymers and inorganic salts were compared, and the apparent viscosity (ηapp) behaviors of copolymer–salt solutions at different shear rates and temperatures were investigated. We found that the ηapp of PAPP and PAMP showed intensive antisalt performance, exhibiting an excellent antipolyelectrolyte effect. The ηapp retention value of 30,000 mg/L PAMP in brine was 86.47 mPa s at 510 s?1, and when the temperature was increased to 90 °C, it was 99.73 mPa s; this was better than that of PAPP under the same conditions. Therefore, PAMP was more applicable as an EOR chemical that have outstanding salt tolerance and temperature resistance. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46235  相似文献   
92.
陈阿强  黄青山  耿淑君  杨超 《化工进展》2018,37(4):1257-1266
喷射反应器是一种重要的化工过程强化设备,可有效强化传质与传热过程、加快反应速率、提高反应产率,近年来在多个领域得到应用。本文对两种典型喷射反应器的结构及其工作原理进行了描述,系统地分析了各操作参数和结构参数对气体吸入量和气泡直径的影响规律,指出研究气体吸入和气泡破碎两种机制的必要性。对采用计算流体力学方法模拟喷射反应器内气液两相流进行了分析,指出Mixture模型适合研究气体吸入量,无法准确描述气泡运动和破碎这两个重要过程,提出采用计算流体力学与群体平衡模型结合的方法进行模拟,关键在于建立适合喷射反应器的气泡破碎频率模型。另外,结合工业应用的实际情况,强调了加入催化剂颗粒相的多相流分析对于指导工业应用的重要意义。  相似文献   
93.
磺酸盐作为降粘剂具有抗温、抗盐的优良特性。筛选合适的降粘剂和磺酸盐基液进行复配是对磺酸盐下游产品的回收利用,具有变废为宝的实用价值,为磺酸盐基液的开发利用开辟了新的途径。测定降粘率的条件经探究确定为:油/水质量比为7∶3,原油乳化时间为1小时,搅拌速率为200 r/s,搅拌时间为2 min。筛选出的表活剂AES和AEO在0.05%和0.5%时与磺酸盐基液达到最佳复配效果,降粘率达到99%左右。经室内驱油物理模拟实验得到最佳的降粘剂配方:磺酸盐(10%)+AES(0.04%)混合驱提高采收率为5.23%。  相似文献   
94.
研究了应用巯基乙酸显色 ,差示分光光度法测定不同含量铁的方法。在 p H9.6氨性介质中 ,铁 ( )与巯基乙酸生成紫红色络合物 ,表观摩尔吸光系数ε53 0 为 8.4× 1 0 3 L·mol- 1· cm- 1,在 2 5 ml体积中铁含量 6 0~ 1 3 0 μg(或 1 1 0~ 1 80 μg)范围内符合比尔定律。本法简便快速 ,选择性好 ,测定范围较广 ,适用于不同量特别是中常含量铁的测定。  相似文献   
95.
SiC–Mo5(Si,Al)3C composites were fabricated by the melt infiltration process, and the infiltration characteristics were studied in detail. Fracture strength and toughness were measured up to 1600°C using a three-point bending test and indentation strength method, respectively. Both fracture strength and toughness significantly increased at 1400°C with respect to the values at room temperature. These increases were mainly attributed to plastic deformation of the infiltrated Mo5(Si,Al)3C phases at elevated temperatures, which acted as ductile toughening inclusions. Compressive creep tests were used to study the creep behavior of the composite in the range of 1550°–1650°C and 150–200 MPa. The stress exponent and activation energy were 1.3 and 277 kJ/mol, respectively. Preliminary oxidation tests showed that the composites exhibited good oxidation resistance at 1500°C because of the formation of a dense oxide scale.  相似文献   
96.
97.
锡基负极材料的理论储锂容量高,但循环稳定性和倍率性能差,难以满足实际应用的需要。我们以四氯化锡、二硫化碳、氨水、石墨烯为原料,采用水热-热处理相结合的方法,合成了氮硫共掺杂石墨烯/硫化锡复合材料(SnS_2@N,S-RGO)。该材料中,硫化锡纳米粒子均匀地生长在石墨烯上,增大了其比表面积,提高了其稳定性和导电性。因此,该复合材料的储锂容量高、倍率性能和循环稳定性好,有望用于高性能锂离子电池。  相似文献   
98.
用生物信息学方法对恶臭假单胞菌铜抗性操纵子基因相似性,蛋白质的亲疏水性,蛋白质高级结构,蛋白质的功能进行分析。结果表明:恶臭假单胞菌铜抗性操纵子与丁香假单胞菌有较高的同源性,而与大肠杆菌距离较远,这意味着该操纵子可能来源于丁香假单胞菌。  相似文献   
99.
Multiwalled carbon nanotubes (MWCNTs) were covalently functionalized with polyhedral oligomeric silsequioxane (POSS). The results of Fourier Transform Infrared Spectroscopy, Raman spectroscopy and Transmission Electron Microscopy indicated that POSS particles were grafted onto MWCNTs. The POSS content determined by thermo‐gravimetric analysis (TGA) was estimated to be ~25 wt%. A stable and superhydrophobic surface characteristic was observed for the film made of MWCNTs grafted with POSS (MWCNT‐g‐POSS) even after an exposure to a high‐humidity environment for three weeks. The water contact angle of the sample was measured to be 160.5 ± 1.1°. Buckypapers were made from both pristine MWCNTs and chemically converted to MWCNT‐g‐POSS. The pore structures of the buckypapers were characterized by mercury intrusion porosimetry and scanning electron microscopy. The flame‐retardant performance of the buckypaper‐based composites was evaluated by TGA and microscale combustion calorimetry (MCC) test. The TGA test results indicated that the MWCNT‐g‐POSS dramatically increased the char residues of the composite. Approximately 72% reduction in peak heat release rate was achieved for the MWCNT‐g‐POSS /resin composite from the MCC testing. The fire‐retardant mechanism was discussed. POLYM. ENG. SCI., 2013. © Society of Plastics Engineers  相似文献   
100.
Oil-phenol-formaldehyde (Oil-PF) resins containing 50 wt% replacement of petroleum phenol with bio-oil were prepared and different catalysts [sodium carbonate (Na2CO3), urea, and magnesium oxide (MgO)] were added in the synthesis process of resins to accelerate the cure. The cure-acceleration effects of catalysts on cure characteristics of oil-PF resins were investigated by using differential scanning calorimetry (DSC), gel time, and a plywood panels test. The results indicated that catalysts presented different accelerating effects on the cure of the oil-PF resin. Both Na2CO3 and MgO can accelerate the oil-PF resin cure at a low temperature; however, urea seemed to have no significant effect on the cure of the resin. The application of Na2CO3- and MgO-accelerated oil-PF resins reduced hot pressing time for the manufacture of three-layer plywood panels. Compared with MgO, Na2CO3 had more significant accelerating effect on the cure of the oil-PF resin.  相似文献   
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