【摘 要】
：
The relationship between the concentration of sodium cations and the properties of faujasite(FAU) zeolite was investigated using a two-step synthesis procedure including (1) formation of amorphous aluminosilicate precursors and separation of amorphous nan
【机 构】
：
State Key Laboratory of Heavy Oil Processing,Key Laboratory of Catalysis of China National Petroleum
论文部分内容阅读
The relationship between the concentration of sodium cations and the properties of faujasite(FAU) zeolite was investigated using a two-step synthesis procedure including (1) formation of amorphous aluminosilicate precursors and separation of amorphous nanoparticles,and (2) transformation of these amorphous particles into zeolite crystals by treatment with alkali solutions(NaOH).Three representative samples including two nano-sized zeolites and one micron-sized zeolite were prepared using different concentrations of sodium hydroxide.The crystallization process of these zeolites was studied in detail by Fourier transform infrared(FTIR) spectrometry,nuclear magnetic resonance spectros-copy(NMR),X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and N2 adsorption.The results indicated that minor changes in the concertation of inorganic cations can significantly shorten the induction period and crystallization time and thus affect the morphology,size and chemical composition of the zeolite crystals.
其他文献
Fluorine is present in the hydroxyapatite mineral in natural tooth enamel,which plays a key role in the prevention of dental caries.The aim of this study is to synthetize the fluorinated urchin-like serried hydroxyapatite(FnUHA) particles with different d
Poly(lactic-co-glycolic acid)(PLGA) microparticles represent an important class of materials used for drug delivery.Current synthesis frequently uses conventional emulsion,where dichloromethane(DCM) is used as the organic phase solvent.Due to the health a
薄壁注塑聚丙烯是一种高附加值聚丙烯新产品.近年来,国内各生产厂家,采用气相法聚合反应工艺和本体气相法聚合工艺均实现了薄壁注塑聚丙烯新产品开发.本文阐述了薄壁注塑专用树脂的特点,以及利用现有工艺开发该类树脂专用料的重要性.从聚合工艺角度,对近五年来国内薄壁注塑专用树脂的研发和生产情况进行了讨论;比较了几种聚合工艺的特点,对研发和生产过程中所使用的催化剂、工艺参数以及产品特点进行了总结,并对薄壁注塑聚丙烯未来的发展趋势进行了展望.
Alkynylplatinum(Ⅱ) bzimpy complexes of trimethylammonium-benzylethynyl ligand have been synthesized and characterized.Complexes with long alkyl chains have been found to exhibit interesting self-assembly properties in the acetonitrile solution.The amphiph
Improving the permeate flux but retaining the rejection of thin-film composite(TFC) polyamide nanofiltration(NF) membrane is a high requirement for desalination.In this work,a calcium ion(Ca2+) coordinated polyamide(PA) NF membrane was prepared by directl
The growth of single-walled carbon nanotubes(SWCNTs) on substrates has attracted great interests because of the potential applications in various fields.Carbon monoxide(CO)was used as the carbon source for the growth of SWCNTs on silicon substrates.Random
Graphene nanoribbons with zigzag edges(ZGNRs) have attracted much attention for their spin-polarized edge states predicted more than 15 years ago.Since the ZGNRs are fabricated on metal substrates using molecular precursors,due to their strong coupling wi
P2-type layered oxide Na0.67Fe0.5Mn0.5O2 is recognized as a very promising cathode material for sodium-ion batteries due to the merits of high capacity,high voltage,low cost,and easy preparation.However,its unsatisfactory cycle and rate performances remai
利用扩链反应活化了胆甾醇或薯蓣皂素端羟基的反应活性,制备了基于胆甾醇或薯蓣皂素衍生物的甾体化合物,并以其为引发剂引发了三亚甲基碳酸酯(TMC)的本体开环聚合反应,制备了胆甾醇或薯蓣皂素封端的聚三亚甲基碳酸酯,采用核磁(1H-NMR)、差示扫描量热仪(DSC)和偏光显微镜(POM)等手段对其结构及液晶性能进行测试表征.结果 表明:胆甾基元或薯蓣皂素基的引入赋予了聚三亚甲基碳酸酯液晶性能,且液晶基元的结构对其液晶性能具有显著影响.
己内酯与丙交酯的开环聚合及其共聚制备生物降解型聚酯是目前的研究热点.为降低聚合催化剂成本与毒性以便使聚合物可以用于食品包装等需求,我们采用三氯化铁在十四醇作用下实现了ε-己内酯的开环聚合以及其与L-丙交酯的共聚.结果 表明:三氯化铁可以高效引发己内酯开环聚合,通过调控聚合条件(如单体/铁比例、温度和时间)能够控制聚合活性与所得聚己内酯的分子量;也可以催化丙交酯开环聚合、以及己内酯与丙交酯的开环共聚.聚合方法以及共聚单体进料顺序显著影响共聚物结构.只有在先加入己内酯后加丙交酯的共聚反应中,才可以制备出嵌段共