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1.
LI Wangliang XING Jianmin XIONG Xiaochao SHAN Guobin & LIU Huizhou . Laboratory of Separation Science Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing China . Graduate School of the Chinese Academy of Sciences Beijing China 《中国科学B辑(英文版)》2005,(6)
More and more stringent regulations of gasoline and diesel oil were proposed with the awareness of environmental protection. Hydrodesulfurization (HDS) is a conventional method to remove sulfur compounds for industrial purpose. The main drawbacks of this … 相似文献
2.
M. Zendehdel A. Mobinikhaledi F. Hasanvand Jamshidi 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(1-2):41-44
Transition metal/Y zeolites were prepared using microwave solid state and aqueous solution ion exchange methods. The activity
of these zeolites was investigated in a conversion of acids to benzimidazoles reaction between 4-methyl-1, 2-phenylenediamine and 3-nitrobenzoic acid. The yield of these reactions increased in order of CuY < Fe2+Y < NiY < CoY < NaY < CrY < MnY < ZnY for both methods. The solid state ion-exchanged zeolites showed higher activity in comparison
to the aqueous solution exchange. Yields of products in the presence of the ZnY zeolite were of the order of 69–83%. It seems
that the Lewis sites are better sites compared to the Bronsted sites for this reaction. 相似文献
3.
Sb/ZSM-5 was obtained by solid-state reaction with the mixture of Sb2O3 and zeolite HZSM-5 under a dry nitrogen flow at 773 K. Characterization of the treated zeolite was undertaken with XRD, 27Al MAS NMR, BET, TGA and FT-IR. The results revealed that part of the antimony oxides migrated into the channels of zeolite, and decreased the Brönsted acid sites in Sb/ZSM-5 remarkably. The other part of antimony oxides together with the amorphous alumino-silicate in the products distributed on the external surface of zeolite ZSM-5 and modified it, while the framework of ZSM-5 in crystal phase was retained. The structure of occluded antimony oxide inside the channels of ZSM-5 was studied by XRD Rietveld method. The result showed that their structure can be described as a chain of non-perfect [Sb5O5(H2O)2]n5n+, which is parallel to the straight channel of ZSM-5. There is about 0.6 [Sb5O5(H2O)2]5+ unit in every cell of the ZSM-5 on an average. 相似文献
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考察了中性分子电对H_2Q/Q在13X型分子筛修饰电极上的电化学行为。发现H_2Q/Q电对在修饰电极上电响应迅速,为双电子可逆反应,不受溶液温度及电极与溶液相对运动的影响,而与溶液的pH值有关。当pH≤2.0时,修饰电极对H_2Q/Q电对的氧化/还原有明显的催化作用. 相似文献
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In this paper we present a series of work covering a range of aspects relating molecular simulation to experiment. The importance
of surface mediation type effects to the adsorption of simple and complex gases is demonstrated. Coupled with the adsorption
of simple gases is their projection area when used for surface area determination. The pressure dependence of a projection
area is demonstrated for argon at 77 and 87.3 K. A simple model is used to account for the degree of graphitisation of a surface
is demonstrated and used to account for the isosteric heat behaviour of non-graphitised carbon blacks. Turning from surfaces
to porous solids, an alternative treatment of experiment data (either sub or super critical) is presented that avoids the
ambiguity of excess amounts adsorbed. Using this method one is able to obtain pore size distributions and amounts adsorbed
without relying on such things as helium expansion volumes. Since this type of method is usually applied to composite solids
we also demonstrate the correct method for calculating the heat of adsorption using independent sets of simulations. The final
topic covered in this paper is an example of the information that can be gained from the heat capacity of an adsorbed phase. 相似文献
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