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41.
CrOx/ SBA-15介孔催化剂上丙烷在二氧化碳气氛中脱氢反应的研究 总被引:2,自引:0,他引:2
The structure and catalytic properties based on Chromium Oxide supported on mesoporous SBA-15 for oxidative dehydrogenation of propane by CO2 have been studied by using X-ray diffraction (XRD), ultraviolet-visible diffuse reflectance spectra (UV-Vis DRS), electron spin resonance (ESR), X-ray photoelectron spectroscopy (XPS) and propane pulsing experiments in the absence of gas-phase O2. It has been shown that propane conversion and propene yield increase with Cr loadings. The propane conversion and propene yield on CrOx(Cr: 10wt%)/SBA-15 catalyst for oxidative dehydrogenation of propane by CO2 at 550 ℃ reach 24.8% and 21.8%, respectively .The results of ESR, UV-Vis DRS and propane pulsing experiments indicate that CrⅢ in the CrOx/ SBA-15 catalyst is the main active species in oxidative dehydrogenation of propane by CO2 and CrⅥ, CrⅤ is inactive in dehydrogenation. 相似文献
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Synthesis and Electrospray Ionization Mass Spectra of N-(1,3, 2-Dioxaphosphorinan-2-ylmethyl)thiophosphoramidates 总被引:1,自引:0,他引:1
N-(1,3,2-Dioxaphosphorinan-2-ylmethyl)thiophosphoramidates were synthesized and determined by NMR spectra and positive ion electrospray ionization mass spectrometry (ESI-MS) in conjunction with tandem mass spectrometry (MS/MS). The fragmentation pathways were investigated. The results show that these characteristic ions in ESI mass spectra are useful in the structural determination of N-(1,3,2-dioxaphosphorinan-2-ylmethyl)- thiophosphoramidates. 相似文献
44.
SrTi0.9M0.1O3-δ钙钛矿型氧化物催化剂甲烷氧化偶联反应性能的研究 总被引:2,自引:0,他引:2
The structure and catalytic properties of SrTi0.9M0.1O3-δ (M=Mg,Al, Zr) perovskite-type catalysts for ox-idative coupling of methane (OCM) have been studied by using X-ray diffraction (XRD),X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption of oxygen(O2-TPD) methods. It has been shown that doping the cations of lower valence (e.g. Mg2+, Al3+) to the B site of SrTi0.9M0.1O3-δ perovskite-type catalysts results in the higher content of adsorbed oxygen species on the surface of catalysts and thus higher C2-selectivity for OCM reaction. It is suggested that the oxygen vacancies of SrTi0.9M0.1O3-δ (M=Mg, Al, Zr) perovskite-type catalysts are the sites responsible for oxygen activation, and the adsorbed oxygen species on the surface of SrTi0.9M0.1O3-δ catalysts are the main active species for OCM reaction. 相似文献
45.
Enantioselective Addition of Phenylacetylene to Aldehydes Catalyzed by Polymer-Supported Sulfonamide
Enantioselective formation of C-C bonds is an area of intense research. Among them, the asymmetric addition of alkynyl reagents to aldehydes is very useful for the synthesis of chiral secondary propargyl alcohols.[1] Recently, many significant homogeneous chiral ligands have been disclosed,[2,3] but very few efficient heterogeneous catalysts have been reported. Herein, we report our research results in the asymmetric addition of phenylacetylene to aldehydes catalyzed by polymer-supported chiral sulfonamide. 相似文献
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现代工业设计中的新技术应用 总被引:1,自引:0,他引:1
科学技术的迅速发展支撑了现代工业设计的进步,针对现代工业设计的核心内容-产品设计的流程,讨论了各种新技术在产品设计各阶段中的应用,重点分析了计算机辅助工业设计(CAID)技术的应用现状及未来发展趋势. 相似文献
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目的探讨了江苏省疾控[2009]97号文件附录A《面制品及海蜇中铝的测定方法》测定面制食品中铝含量。方法样品经干法消化后,在乙二胺-盐酸缓冲溶液中,三价铝在十六烷基三甲基溴化铵阳离子表面活性剂存在下,与铬天青S形成绿色三元体系,其吸光度与铝的含量在一定含量范围内成正比。结果样品消化液在定容30 min时测定结果接近中位值,方法线性系数r=0.999 7,相对标准偏差在3.3%~3.7%之间,样品回收率在88.9%~96.4%。结论该法操作简便,灵敏度高,适用于各实验室开展检测。 相似文献