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Excessive application of nitrogen (N) fertilizer is the main cause of N loss and poor use efficiency in winter wheat (Triticum aestivumL.) production in the North China Plain (NCP). Drip fertigation is considered to be an effective method for improving N use efficiency and reducing losses, while the performance of drip fertigation in winter wheat is limited by poor N scheduling. A two-year field experiment was conducted to evaluate the growth, development and yield of drip-fertigated winter wheat under different split urea (46% N, 240 kg ha−1) applications. The six treatments consisted of five fertigation N application scheduling programs and one slow-release fertilizer (SRF) application. The five N scheduling treatments were N0–100 (0% at sowing and 100% at jointing/booting), N25–75 (25% at sowing and 75% at jointing and booting), N50–50 (50% at sowing and 50% at jointing/booting), N75–25 (75% at sowing and 25 at jointing/booting), and N100–0 (100% at sowing and 0% at jointing/booting). The SRF (43% N, 240 kg ha−1) was only used as fertilizer at sowing. Split N application significantly (P<0.05) affected wheat grain yield, yield components, aboveground biomass (ABM), water use efficiency (WUE) and nitrogen partial factor productivity (NPFP). The N50–50 and SRF treatments respectively had the highest yield (8.84 and 8.85 t ha−1), ABM (20.67 and 20.83 t ha−1), WUE (2.28 and 2.17 kg m−3) and NPFP (36.82 and 36.88 kg kg−1). This work provided substantial evidence that urea-N applied in equal splits between basal and topdressing doses compete economically with the highly expensive SRF for fertilization of winter wheat crops. Although the single-dose SRF could reduce labor costs involved with the traditional method of manual spreading, the drip fertigation system used in this study with the N50–50 treatment provides an option for farmers to maintain wheat production in the NCP.

The aim of this study was to evaluate the clinical efficacy of Xuanfei Baidu Decoction (XBD) combined with conventional drug therapy compared with conventional medicine alone in patients with coronavirus disease 2019 (COVID-19).

Rod fastening rotor (RFR) is the core part of gas turbine, the degradation of RFR has great effect on gas turbine's performance. One of the main reasons which cause the RFR performance degradation is creep damage, while few studies have been carried out in terms of it so far. In order to analyze the influence of preload on virtual material parameters, a dynamic model of RFR considering interface contact effect was built. Then equivalent stiffness of RFR and elements was analyzed as well. Furthermore, creep damage of elements under higher stress were analyzed with damage mechanics to get their influence on the total damage. Likewise, RFR were analyzed with damage mechanics to get the connection between the total damage and rupture life. The results showed that connection between the total damage and rupture life was a complicated, non-linear process. Moreover, the rods of turbine and combustion chamber were the biggest influencing factors. The results of this dissertation can be a support for structural design and life prediction of RFR.

Focuses on the liberalization of the insurance industry in Singapore. Purpose of the Singapore Monetary Authority in liberalizing the industry; Role of the insurance industry in the country; Specialization encourage by the Singapore Monetary Authority.