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A unique method to prepare Zn-P co-modified hierarchical ZSM-5 zeolites was developed. The ZSM-5 zeolite was directly synthesized by a dry gel conversion without adding any templates or seeds. Afterwards, the hierarchical structure was endowed to the ZSM-5 zeolite by the sequential desilication-dealumination. Zn and P species were then introduced into the hierarchical ZSM-5 zeolites by the impregnation method and their activity in methanol to aromatics process was investigated. It was found that the Zn-P co-modified hierarchical ZSM-5 zeolites possessed more Zn-related Lewis acid sites, and the ratio of Zn(OH)+/ZnO was increased. The catalytic evaluation results revealed that the benzene, toluene and xylene (BTX) and aromatics selectivity were significantly improved from 20.59% and 29.41% of pristine ZSM-5 zeolite to 28.12% and 41.88% of Zn-P co-modified hierarchical counterpart (1.5Zn0.3P/HZSM-5), respectively. Owing to the introduced highly stable Zn-P co-modified hierarchical structures, the lifetime (conversion not less than 99%) of ZSM-5 zeolite during methanol to aromatics reaction was increased from 6 h to 18 h.

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With the rapid development of information technology, more and more requesters need accessing the services in different access domains, which make the access process in cross-domain become more difficultly. The traditional access control models couldn’t solve the access process for their design limitations and diversity access policies. Usage control model (UCON) was proposed to strengthen the expression of access control model, but UCON is only a conceptual model. How to use the UCON in access process? It is worthwhile to further study. Extensible access control markup language (XACML) is an open standard XML-based language, which can be used to describe the security policy. In order to solve the access process in different access domains, based on XACML, access process of data-flow in cross-domain usage control model is proposed in the paper. Access process of data-flow cross different domains in XACML is introduced to solve the cross-domain problem. Finally, a small example is given to verify the effectiveness of access process.