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101.
In this work, (a) complexation reaction of zirconium tetra-n-butylate, Zr(OBu
n
)4, with MAc and different organic acids, (b) the hydrolysis reaction of modified Zr species, and (c) the polymerization reaction of complex products are studied. Zr(OBu
n
)4 was reacted with different mole ratios of methacrylic acid (MAc) at room temperature and the maximum combination ratio was found to be 1:2 [Zr(OBu
n
)4:MAc] by FT-IR. The modification of zirconium tetra-n-butylate with the acid mixtures [methacrylic acid-acetic acid (MeCOOH), methacrylic acid-propionic acid (EtCOOH), methacrylic acid-butyric acid (PrCOOH)] was made for a combination ratio of 1:1:1 [MAc:RCOOH:Zr(OBu
n
)4; R: Me, Et, Pr] and the products were characterized by1H-NMR, FT-IR, and UV spectroscopies. Following their synthesis, hydrolysis of the complexes with various amounts of water and polymerization with benzoyl peroxide were realized. The hydrolysis and polymerization products of the complexes were studied by Karl-Fischer coulometric titration and thermal analysis, respectively. Methyl ethyl ketone(MEK) and chloroform were chosen as solvents. 相似文献
102.
103.
Zeolite beta with a low SiO2/Al2O3 ratio was synthesized by a novel two-step process.The synthesized sample was characterized with XRD,SEM,FTIR,and N2 adsorption-desorption and solid-state MAS NMR.The results showed that aluminium species were inserted into the framework of zeolite beta.The BET surface area,volume,and particle size of the zeolite beta sample decreased with decreasing SiO2/Al2O3 ratio.Our process was proved an efficient route to synthesize zeolite beta with a low SiO2/Al2O3 ratio. 相似文献
104.
105.
The synthesis and magnetostriction of PrxTb1-x.Fe2, PrxTb1-x Fe2BO2 and PrxTb1-x(Fe0.6Co0.4)2 alloys were investigated in this study. The addition of boron or cobalt atom in PrxTb1-xFe2 could effectively prevent the formation of non-cubic phases, and Pr concentration limit was successfully increased from 0.2 to 0.4. X-ray step scanning for the PrxTb1-xFe2BO2 and PrxTb1-x(Fe0.6Co0.4)2 alloys showed that PrFe2 possessed a large spontaneous magnetostriction λ1111. 相似文献
106.
The synthesis of alternative reaction paths leading to a desired chemical has received increasing attention in the recent past. A procedure to develop new reaction schemes in a systematic manner was reviewed by the authors ( [ 1 -3] ). The algorithm presented in these earlier papers implied the generation of an infinite number of reaction paths. The thermodynamic feasibility is a preliminary screening which reduces the number of chemical production schemes. Further screening is necessary, taking into account considerations which are related to economics, processing, safety and so on. Some constraints related with role specification, gross added value and demand/supply requirements are analysed in this paper. Examples illustrate the application of the screening procedure, showing that the addition of a few constraints results in a dramatic decrease of alternative reaction paths. 相似文献
107.
运用XD工艺制备了颗粒增强TiAl基复合材料。增强颗粒均匀分布于TiAl基体中并细化TiAl合金。通过在TiB_2/TiAl、TiC/TiAl复合材料中加入适量的Si,颗粒增强TiAl基复合材料的室温延性得到了改善。 相似文献
108.
介绍了美国C.F布朗公司大型合成氨装置根据操作条件和介质腐蚀程度不同,如何选择管道和设备材料,并对其用材进行逐一剖析。 相似文献
109.
VNS反应合成LLM-116 总被引:2,自引:0,他引:2
以1,3-二硝基吡唑为原料,经热重排、氨气中和得到3,5-二硝基吡唑铵盐,然后酸化得到3,5-二硝基吡唑。以三甲基肼碘化物(TMHI)作为异常亲核取代氢(VNS)反应试剂,与3,5-二硝基吡唑在叔丁醇钾为催化剂,利用VNS反应合成4-氨基-3,5-二硝基吡唑(LLM-116)。采用红外分析、核磁共振、元素分析等仪器鉴定了其结构,讨论了VNS反应机理及影响因素。通过实验,得出最佳VNS反应试剂为TMHI,反应时间为4h,反应温度为25℃,收率达到60%。 相似文献
110.