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991.
992.
研究我国大型优质神木煤田12个煤样的主要性质,对其水煤浆特性的影响。实验表明,煤中水分和含氧官能团是主要因素,水分中以最高内在水分与水煤浆浓度呈线性相关,提出以最高内在水分作为评价指标。并研究了煤浆的改性方法,一是加热方法使水分和官能团脱除,煤表面亲水性降低,使煤浆浓度大幅度提高,二是除去煤中可溶无机离子,可使煤浆粘度降低,并添加某些电解质有可能提高稳定性。 相似文献
993.
乙烯装置急冷系统能量回收工艺特点分析 总被引:1,自引:0,他引:1
乙烯装置急冷系统接收来自炉区的高温裂解气,为降低乙烯装置能耗,必须尽可能回收裂解气中的热量。文中针对KBR乙烯流程,介绍了乙烯装置急冷系统能量逐步回收的过程及其工艺特点。 相似文献
994.
995.
近年来作为俄罗斯经济支柱产业的石油工业,在自身发展过程中,其体制改革和生产等方面都取得一些进步,但目前仍存在着许多急待解决的重要问题,因此对俄罗斯石油工业进行一些概括性的分析和梳理对深刻认识俄罗斯石油工业未来的发展趋势是有益的。 相似文献
996.
Nanoscale TiO2 particle filled poly(vinylidenefluoride-co-hexafluoropropylene) film is characterized by investigating some properties such as surface morphology, thermal and crystalline properties, swelling behavior after absorbing electrolyte solution, chemical and electrochemical stabilities, ionic conductivity, and compatibility with lithium electrode. Decent self-supporting polymer electrolyte film can be obtained at the range of <50 wt% TiO2. Different optimal TiO2 contents showing maximum liquid uptake may exist by adopting other electrolyte solution. Room temperature ionic conductivity of the polymer electrolyte placed surely on the region of >10−3 S/cm, and thus the film is very applicable to rechargeable lithium batteries. An emphasis is also be paid on that much lower interfacial resistance between the polymer electrolyte and lithium metal electrode can be obtained by the solid-solvent role of nanoscale TiO2 filler. 相似文献
997.
A series of air-stable, late transition, metal-based initiators with the structures ML2(CCR)2 (M=Pd and Ni; L=PPh3 and Pn-Bu3; R=Ph and CH2OH) for the polymerization of (dimethylamino)ethyl methylate (DMAEMA) were developed. Transition metal, phosphine, alkynyl, as well as solvents exhibited significant influence on the polymerization. Among them, Pd(CCPh)2(PPh3)2 (PPP) shows the highest activity in CHCl3 for DMAEMA polymerization. The PDMAEMA obtained is a syndiotactic polymer with high number-average molecular weight (Mn) of 20.2 × 104. A free radical polymerization mechanism with some ATRP characteristics was proposed for the present polymerization. 相似文献
998.
2,7‐Bis(4‐aminophenoxy) naphthalene (BAPN), a naphthalene‐containing diamine, was synthesized and polymerized with a 3,3′,4,4′‐benzophenone tetracarboxylic dianhydride (BTDA) to obtain a polyimide (PI) via thermal imidization. To enhance the thermal and mechanical properties of the polymer, PI–Montmorillonite (MMT) nanocomposites were prepared from a DMAc solution of poly(amic acid) and a DMAc dispersion of MMT, which were organo‐modified with various amounts of n‐dodecylamine (DOA) or cetylpyridium chloride (CPC). FTIR, XRD, and TEM (transmission electron microscopy) were used to verify the incorporation of the modifying agents into the clay structure and the intercalation of the organoclay into the PI matrix. Results demonstrated that the introduction of a small amount of MMT (up to 5%) led to the improvement in thermal stability and mechanical properties of PI. The decomposition temperature of 5% weight loss (Td,5%) in N2 was increased by 46 and 36°C in comparison with pristine PI for the organoclay content of 5% with DOA and CPC, respectively. The nanocomposites were simultaneously strengthened and toughened. The dielectric constant, CTE, and water absorption were decreased. However, at higher organoclay contents (5–10%), these properties were reduced because the organoclay was poorly dispersed and resulted in aggregate formation. The effects of different organo‐modifiers on the properties of PI–MMT nanocomposite were also studied; the results showed that DOA was comparable with CPC. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci, 2006 相似文献
999.
Zunli Mo Yinxia Sun Hong Chen Ping Zhang Dandan Zuo Yanzhi Liu Hejun Li 《Polymer》2005,46(26):1046-12676
An easy process for the synthesis of poly(methyl methacrylate)/Ce(OH)3, Pr2O3/graphite nanosheet (PMMA/Ce(OH)3, Pr2O3/NanoG) composite was developed. Graphite nanosheets (NanoG) were prepared by treating the expanded graphite with sonication in aqueous alcohol solution. The PMMA/Ce(OH)3, Pr2O3/NanoG composites were prepared via in situ polymerization of MMA monomer in the presence of graphite nanosheets and Ce(OH)3, Pr2O3 through reverse micelle template, in which the methyl methacrylate was designated as the oily phase. The composites were then dispersed with chloroform and coated on glass slides to form films. Scanning and transmission electron microscopy were used to characterize the structure and dispersion of the graphite nanosheets and the composites. The results showed that the high-aspect-ratio structure of the nanosheets played an important role in forming a conducting network in the PMMA matrix. From thermogravimetric analysis, the introduction of graphite nanosheets and inorganic nanopartices exhibited a beneficial effect on the thermal stability of PMMA. 相似文献
1000.
锆莫来石材料的反应烧结机制和显微结构特征 总被引:5,自引:0,他引:5
研究了用锆英石和工业氧化铝合成锆莫来石材料的反应烧结过程和显微结构。结果表明,添加适量MgCl2·6H2O可以促进反应烧结进程。锆英石大颗粒完全分解以后形成ZrO2聚集体,结构中出现封闭气孔可能与ZrO2聚集体有密切关系。加入MgCl2·6H2O后锆莫来石材料显微结构的主要特征:ZrO2有聚集体和均匀分布两种赋存形式;封闭气孔一般与ZrO2聚集体相邻。 相似文献