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就职演讲PPT模板the draft of academic presentation 国际会议的口头报告模板,每页ppt你需要讲什么东西需要分页详细写,尽量口语化,如下是本人参加比利时会议的模板,供大家参考。 p1 开场白: the tile of my academic presentation is “the preparation and catalytic performance of porous silica nanotube functioned with heteroatoms” i shall only take ten minutes of your time. i will talk about the topic on the preparation of porous materials. p2 p3 the content is listed as follows. p4 p5 but due to lack of active sites, we have to introduce organic or inorganic species as active sites. and the catalytic performance need to be further improved. p6 as we know, the three factors including activity, scale and diffusion factor play decisive role in the catalysis, affecting the yield, selectivity, stability strongly. in our presentation, we mainly focus on the influence of scale factor on the catalysis. p7 due to lack of active sites for mesoporous silica, two main methods (surface loading, modified framework) are widely reported, by which various organic or inorganic active sites can be immobilized on the surface or incorporated into the framework of mesopoous silica. p8 though various morphologies of mesoporos silica were widely synthesized, the synthesis of the mesoporos silica, with three simultaneous characteristics including doped metal, mesoporous structure and specific morphology, is always a challenge, which is rarely reported. in other words, for our case exploring a proper condition, at which the silicon and metal sources can simultaneously hydrolyze, can ensure a desired material. p9 next, lets look at the synthetic steps. firstly,. then, . after that, . at last, we obtained the products. p10 in this work, by changing the synthesis conditions, such as , and so on, the pure mesoporous silica with different morphologies were synthesized, including nanosphere, nanorod, helix, capsule and nanotube. we will focus on the preparation and catalytic application of mesoporous silica with nanotube morphology. p11 the sem images of samples: a1, a2, a3 are shown in the figure. it can be seen that sample a1 is nanowire-like with length of about 2m and diameter of about 100nm. when the amount of . is 0.04 g, the morphology of sample a2 became to be short and thick rods and the size is about 1m in length and 400nm in diameter, respectively. with further increasing the amount of ., the sample a3 and a4 turned to be spherical morphology. it also can be seen that the diameters of samples a3 and a4 are substantially the same about 450nm. however, the spherical morphology of a4 is more regular than that of a3. the xrd patterns showed four reflection peaks attributed to (100), (110), (200) and (210), respectively, due to the hexagonal sructure. p12 then, we keep the same amount of ., increasing the amount of . we found that the length increased gradually. the xrd patterns also showed the hexagonal sructure of samples b1, b2, b3, b4. p13 moreover, an additional proof of the hexagonal symmetry structure is given by tem and the ft pattern. the n2 adsorption-desorption isotherms of the samples b1, b2, b3, b4 exhibit a typical type-iv isotherm. according to the table of structur
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