The 1Cr18Ni9Ti stainless steel with Al-Si/Al-Si-Cr coatings is prepared by slurry process and vacuum diffusion, and the hot corrosion behavior of the stainless steel with/without the coatings is studied under the condition of Na2SO4 film at 950 °C in air. Results show that the corrosion kinetics of stainless steel, the stainless steel with Al-Si coating and the stainless steel with Al-Si-Cr coating follow parabolic laws in several segments. After 24 h corrosion, the sequence of the mass gain for the three alloys is the stainless steel with Al-Si-Cr coating < the stainless steel with Al-Si coating < the stainless steel without any coating. The corrosion products of the three alloys are layered. Thereinto, the corrosion products of stainless steel without coating are divided into two layers, where the outside layer contains a composite of Fe2O3 and FeO, and the inner layer is Cr2O3. The corrosion products of the stainless steel with Al-Si coating are also divided into two layers, of which the outside layer mainly consists of Cr2O3, and the inner layer is mainly SiO2. The corrosion film of the stainless steel with Al-Si-Cr coating is thin and dense, which combines well with substrate. Thereinto, the outside layer is mainly Cr2O3, and the inside layer is Al2O3. In the matrix of all of the three alloys, there exist small amount of sulfides. Continuous and protective films of Cr2O3, SiO2 and Al2O3 form on the surface of the stainless steel with Al-Si and Al-Si-Cr coatings, which prevent further oxidation or sulfide corrosion of matrix metals, and this is the main reason for the much smaller mass gain of the two alloys than that of the stainless steel without any coatings in the 24 h hot corrosion process.

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Whether the mobile government service in this paper can meet the use standard of “4-b”. The mobile government service can be divided into four development stages since its emergence: one is to solve the main problem of how to build the basic framework of mobile government service, which is based on the push stage of government information resources of information offline browsing system; the second is to solve the main problem of how to identify the user’s identity conveniently, which is based on the user identity authentication stage of the mobile client; the third is to solve the main problem of fast interaction between server and client, which is based on the intelligent document processing stage of QR code; fourthly, it solves the main problem of fast access to services, which is based on the service aggregation stage of “App + applet”. These four stages are inherited from each other, which is a process of continuous improvement. With the solution of service aggregation, the mobile government service will fully meet the “4-b” usage standard and become the mainstream form of e-government.