The olivine-type LiFePO 4 /C cathode materials were prepared via carbothermal reduction method using cheap Fe 2 O 3 as raw material and different contents of glucose as the reducing agent and carbon source. Their structural and morphological properties were investigated by X-ray diffraction, scanning electron microscope, transmission electron microscope, and particle size distribution analysis. The results demonstrated that when the content of the carbon precursor of glucose was 16 wt.%, the synthesized powder had good crystalline and exhibited homogeneous and narrow particle size distribution. Even and thin coating carbon film was formed on the surface of LiFePO 4 particles during the pyrolysis of glucose, resulting in the enhancement of the electronic conductivity. Electrochemical tests showed that the discharge capacity first increased and then decreased with the increase of glucose content. The optimal sample synthesized using 16 wt.% glucose as carbon source exhibited the highest discharge capacity of 142 mAh g −1 at 0.1C rate with the capacity retention rate of 90.4% and 118 mAh g −1 at 0.5C rate.

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The city acts as political, culture, and economic center, with fast development of chain business, e-commerce, and other modern trade industries and urban advance of rural integration's process, the consumption scale and category of fresh agricultural constantly grow, and it must raise urgent needs of city cold chain logistics, while also cause huge of traffic pressure, which makes contradictions between external uneconomic nature of city distribution and the sustainability of city economic development more explicit. Fresh agricultural products are necessities to urban residents, and it is basic guarantee of urban life stability to build a perfect cold chain logistics system for fresh agricultural products, it is also basic conditions supporting the development of the city. This article studies on cold chain logistics system for fresh agricultural products and analyzes the situation of the city-oriented cold chain logistics system for fresh agricultural products, and its development trend.

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decrease in the yearly mortality rate during the study period: coefficient per quarter, SE = À0Á0081 AE 0Á0033 (95% CI À0Á015 to À0Á0011), P = 0Á025 (Fig. 1). Multivariate analyses confirmed this decrease: coefficient per quarter, SE = À0Á0089 AE 0Á0032 (95% CI À0Á016 to À0Á0017), P = 0Á020. In this cohort study, we found a significant decrease in mortality over 20 years in both univariate and multivariate analysis that was not explained by a modification in patients' profiles, including their severity, except for those receiving ciclosporin. Indeed, 118 patients (33%) received ciclosporin, mainly from 2005. A prospective short trial performed from 2005 to 2007 in our dermatology department suggested a mild benefit of ciclosporin on mortality and healing. 6 However, in a larger study using a propensity score methodology, including retrospectively all ciclosporin-treated patients at the same dermatology department from 2005 to 2016, the usefulness of ciclosporin could not be confirmed. 7 Thus, we hypothesize that the decrease in mortality in our centre is due to improved supportive care rather than ciclosporin treatment. 1,8 All of these measures were optimized by the creation of our reference centre in 2005 in the context of a national health policy for rare diseases, with implementation of a dedicated medical and paramedical team, a multidisciplinary approach to the acute phase and sequelae, teaching, and recently updated French guidelines. 8 We included in the multivariate analysis most of the variables associated with mortality, including ciclosporin treatment. However, a limitation of the study is the retrospective design, including the failure to take into account some other confounding factors. Mortality due to SJS, overlap syndrome and TEN has decreased over time in our centre. This could have resulted from a progressive improvement of supportive care.