The paper presents selected experience of the authors resulting from the optimization tests of double-regulated water turbines. Among the methods for measuring the discharge through the turbine used in such tests, par...The paper presents selected experience of the authors resulting from the optimization tests of double-regulated water turbines. Among the methods for measuring the discharge through the turbine used in such tests, particular attention was paid to index methods allowing to measure the relative discharge through the turbine-the index current meter method and the methods based on measuring the differential pressure between two points properly located at the turbine flow system (i.e., Winter-Kennedy method). These methods contribute to effective reduction of the cost of optimizing the turbine that is extremely important for small hydropower plants regarding installed capacity. The paper presents selected examples of the optimization tests and experiences that arise from these tests.展开更多
The isolation distance required for field trials of genetically modified (GM) rapeseed varies widely worldwide, with a 50-400 m distance in most nations contrasting with a minimum 1000-m isolation distance in China. T...The isolation distance required for field trials of genetically modified (GM) rapeseed varies widely worldwide, with a 50-400 m distance in most nations contrasting with a minimum 1000-m isolation distance in China. The goal of this study was to evaluate the relevance of current regulations in China regarding the isolation distance needed for GM rapeseed trials. A pollen flow experiment was conducted based on the design of concentric circles, with the GM plants in a 20-m diameter circle at the centre, surrounded by non-GM plants to a distance 60 m from the perimeter of the circle containing GM plants. The rate of pollen flow was the highest at the isolation distance of 0.5 m, where it ranged from 2.3091% to 2.6711%. The general pattern of the pollen flow rate (y) with distance (x) was well described by the equation y = 1.3936x-0.9136 (R 2 = 0.9950). The long-distance pollen flow tested at the isolation distance of 800 m was 0.0018%, which agrees with the theoretical prediction. The results suggested that 300 m, rather than 1000 m, is a reasonable distance to ensure a tolerable threshold of pollen flow (less than 0.01%) under conditions of winter rapeseed production in China.展开更多
文摘The paper presents selected experience of the authors resulting from the optimization tests of double-regulated water turbines. Among the methods for measuring the discharge through the turbine used in such tests, particular attention was paid to index methods allowing to measure the relative discharge through the turbine-the index current meter method and the methods based on measuring the differential pressure between two points properly located at the turbine flow system (i.e., Winter-Kennedy method). These methods contribute to effective reduction of the cost of optimizing the turbine that is extremely important for small hydropower plants regarding installed capacity. The paper presents selected examples of the optimization tests and experiences that arise from these tests.
基金supported by the National Natural Science Foundation of China (30900217)the Public Welfare Industry-Special Research Project of Ministry of Environmental Protection (201109028)+3 种基金Natural Science Foundation of Jiangsu Province (BK2011410)"333" High-level Personnel Training Project of Jiangsu ProvinceJiangsu Province "Cyan-blue"Cultivation Project for Middle-aged academic leaders"Cyan-blue"Project for Outstanding Scientific and Technological Innovation Team of Jiangsu Province
文摘The isolation distance required for field trials of genetically modified (GM) rapeseed varies widely worldwide, with a 50-400 m distance in most nations contrasting with a minimum 1000-m isolation distance in China. The goal of this study was to evaluate the relevance of current regulations in China regarding the isolation distance needed for GM rapeseed trials. A pollen flow experiment was conducted based on the design of concentric circles, with the GM plants in a 20-m diameter circle at the centre, surrounded by non-GM plants to a distance 60 m from the perimeter of the circle containing GM plants. The rate of pollen flow was the highest at the isolation distance of 0.5 m, where it ranged from 2.3091% to 2.6711%. The general pattern of the pollen flow rate (y) with distance (x) was well described by the equation y = 1.3936x-0.9136 (R 2 = 0.9950). The long-distance pollen flow tested at the isolation distance of 800 m was 0.0018%, which agrees with the theoretical prediction. The results suggested that 300 m, rather than 1000 m, is a reasonable distance to ensure a tolerable threshold of pollen flow (less than 0.01%) under conditions of winter rapeseed production in China.