As a mega-city constrained by resources and the environment, Beijing has developed a leading service sector, and it is necessary to evaluate the service sector circular economy in this major global city. Here, we establish an indicator system including internal subsystem (economic production, resources consumption, waste emissions, and waste recycling), external subsystem (industry correlation) and mutualistic subsystem (society development), and use AHP modeling to evaluate the period from 2000 to 2013. We found that the development of the service sector circular economy in Beijing experienced an increase from 2000 to 2008, then a decrease from 2009 to 2013. This change mainly resulted from the decrease in Beijing's GDP following the international financial crisis in 2008. The internal subsystem greatly influences the service sector circular economy:synthetic weight of economic production, resource consumption, waste emissions and waste recycling was 0.367,0.136,0.136 and 0.075, respectively. Within the external subsystem, industrial correlation has a weak connection with Beijing's service sector circular economy with asynthetic weight of 0.143, this result illustrates that the development of the service sector circular economy has an intimate relationship with other cities or provinces around Beijing, such as Tianjin and Hebei. As are presentative of the mutualistic subsystem, society development has a positive nexus with the service sector circular economy with asynthetic weight of 0.143, proving that the development of the service sector circular economy can improve the service sector employment ratio in Beijing. We conclude with some suggestions on how to develop the service sector circular economy in Beijing.

With the research and discussion about different kinds of methods generating random number by computer and encryption algorithm, REA is raised from a practical standpoint. REA can make key sequence closer to true random sequence, thus it ensures data security. Experiments show that the algorithm has many characteristics: understanding easily, practicality, encrypting faster, increasing the difficulty of deciphering and less spending of the system.

The alpine peatlands in western Sichuan Province are currently experiencing aridification. To understand the effects of aridification on the characteristics of organic carbon release from alpine soils, the soil in the northwest Sichuan Plateau was investigated. Soil columns were incubated under different moisture conditions in situ and in the laboratory, and ultraviolet-visible absorption spectroscopy and three-dimensional fluorescence spectroscopy were used to assess the soil dissolved organic carbon (DOC) levels. The results revealed that (1) the cumulative release of DOC from alpine soil in the northwest Sichuan Plateau decreased with decreasing moisture content. The cumulative release of soil DOC in the laboratory (0–5 cm soil reached 1.93 ± 0.43 g/kg) was greater than that from soil incubated in situ (0–5 cm soil reached 1.40 ± 0.13 g/kg); (2) the cumulative release of DOC in 0–5 cm soil exhibited the greatest response to changes in water content, and the cumulative release of DOC from the 0–5 cm soil layer (1.40 ± 0.13 g/kg) was greater than that from the 5–15 cm soil layer (1.25 ± 0.03 g/kg); and (3) UV-visible absorption spectra and 3D fluorescence spectral characteristics indicated that aridification increases the content of chromophoric dissolved organic matter (CDOM) components with strong hydrophobicity, especially tyrosine components (surface soil increased 39.59~63.31%), in alpine soil DOC. This increase in hydrophobic CDOM components enhances the aromaticity and degree of humification of DOC. Our results revealed that drought inhibits the release of soil DOC, which is unfavorable for the sequestration of organic carbon in alpine soils, potentially resulting in the loss of soil carbon pools and further degradation of alpine ecosystem functions.