[Objective] The aim was to select simplified high-yielding cultivation technology of rice. [Method] The research explored three methods of farmland prepara- tion, transplanting, and fertilization including shallow rot...[Objective] The aim was to select simplified high-yielding cultivation technology of rice. [Method] The research explored three methods of farmland prepara- tion, transplanting, and fertilization including shallow rotary tillage and deep ploughing, mechanical transplanting and hand transplanting, controlled-release fertilizer and quantitative fertilization in order to investigate effects of different treatment groups on rice characteristics, economic characteristics, as well as labor saving, yield increasing and profit improving. [Result] Rice increased by 596.4-809.55 kg/hm2, labor saving reached 120-135 per hm2, and profit improved in the range from 5 521.39 to 8 727.48 yuan/hm2 in the treatment groups by combinations of shallow rotary tillage, mechanical transplanting, and controlled-release fertilizer, of shallow rotary tillage, mechanical transplanting, and quantitative fertilization, and of deep ploughing, mechanical transplanting, and controlled release fertilizer. [Conclusion] The three models are of promising prospects in production.展开更多
The highly-efficient dry separation technique using a gas-solid fluidized bed is very beneficial for increasing coal grade and optimizing the utilization of coal resources.The size distribution of the solid medium(e.g...The highly-efficient dry separation technique using a gas-solid fluidized bed is very beneficial for increasing coal grade and optimizing the utilization of coal resources.The size distribution of the solid medium(e.g.,magnetite powder) used in this technique is one of key factors that influences fluidization and separation performance.It is,therefore,urgent to prepare medium in a way that operates at low cost and high efficiency.Grinding experiments were performed using a planetary ball mill equipped with a frequency converter.The effect of fed mass,rotation frequency of the mill,grinding time and the ball-size ratio on grinding performance was investigated.The grinding parameters were optimized by numerical calculations using Artificial Neural Network(ANN) in Matlab.A regression equation for predicting the yield of the desired product(i.e.,0.3～0.15 mm magnetite powder) is proposed.The maximum yield of 0.3～0.15 mm particles was 47.24%.This lays a foundation for the industrial-scale production of the solid medium required for separation with a magnetite-powder fluidized bed.展开更多
Camellia seed oil （CSO） is rich in oleic acid and has a high number of active components, which give the oil high nutritional value and a variety of biological activity. The aim of the present study was to determine...Camellia seed oil （CSO） is rich in oleic acid and has a high number of active components, which give the oil high nutritional value and a variety of biological activity. The aim of the present study was to determine the changes in the content and distribution of total polar compounds （TPC） in CSO during heating. TPC were isolated by means of preparative flash chromatography and further analyzed by high-performance size-exclusion chromatography （HPSEC） The TPC content of CSO increased from 4.74% to 25.29%, showing a significantly lower formation rate as compared to that of extra virgin olive oil （EVOO） and soybean oil （SBO） during heating. Furthermore, heating also resulted in significant differences （P〈0.05） in the distribution of TPC among these oils. Though the content of oxidized triacyl- glycerol dimers, oxidized triacylglycerol oligomers, and oxidized triacylglycerol monomers significantly increased in all these oils, their increased percentages were much less in CSO than those in EVOO, indicating that CSO has a greater ability to resist oxidation. This work may be useful for the food oil industry and consumers in helping to choose the correct oil and to decide on the useful lifetime of the oil.展开更多
文摘[Objective] The aim was to select simplified high-yielding cultivation technology of rice. [Method] The research explored three methods of farmland prepara- tion, transplanting, and fertilization including shallow rotary tillage and deep ploughing, mechanical transplanting and hand transplanting, controlled-release fertilizer and quantitative fertilization in order to investigate effects of different treatment groups on rice characteristics, economic characteristics, as well as labor saving, yield increasing and profit improving. [Result] Rice increased by 596.4-809.55 kg/hm2, labor saving reached 120-135 per hm2, and profit improved in the range from 5 521.39 to 8 727.48 yuan/hm2 in the treatment groups by combinations of shallow rotary tillage, mechanical transplanting, and controlled-release fertilizer, of shallow rotary tillage, mechanical transplanting, and quantitative fertilization, and of deep ploughing, mechanical transplanting, and controlled release fertilizer. [Conclusion] The three models are of promising prospects in production.
基金supported by the National Natural Science Foundation of China (Nos.50921002 and 90510002)the National High Technology Research and Development Program of China (No.2007AA05Z318)
文摘The highly-efficient dry separation technique using a gas-solid fluidized bed is very beneficial for increasing coal grade and optimizing the utilization of coal resources.The size distribution of the solid medium(e.g.,magnetite powder) used in this technique is one of key factors that influences fluidization and separation performance.It is,therefore,urgent to prepare medium in a way that operates at low cost and high efficiency.Grinding experiments were performed using a planetary ball mill equipped with a frequency converter.The effect of fed mass,rotation frequency of the mill,grinding time and the ball-size ratio on grinding performance was investigated.The grinding parameters were optimized by numerical calculations using Artificial Neural Network(ANN) in Matlab.A regression equation for predicting the yield of the desired product(i.e.,0.3～0.15 mm magnetite powder) is proposed.The maximum yield of 0.3～0.15 mm particles was 47.24%.This lays a foundation for the industrial-scale production of the solid medium required for separation with a magnetite-powder fluidized bed.
基金Project supported by the National Natural Science Foundation of China(No.31430067)the Northeast Agricultural University Innovation Foundation for Postgraduate of Heilongjiang Province(No.yjscx14058)the National High-Tech R&D Program(863)of China(No.2013AA102104)
文摘Camellia seed oil （CSO） is rich in oleic acid and has a high number of active components, which give the oil high nutritional value and a variety of biological activity. The aim of the present study was to determine the changes in the content and distribution of total polar compounds （TPC） in CSO during heating. TPC were isolated by means of preparative flash chromatography and further analyzed by high-performance size-exclusion chromatography （HPSEC） The TPC content of CSO increased from 4.74% to 25.29%, showing a significantly lower formation rate as compared to that of extra virgin olive oil （EVOO） and soybean oil （SBO） during heating. Furthermore, heating also resulted in significant differences （P〈0.05） in the distribution of TPC among these oils. Though the content of oxidized triacyl- glycerol dimers, oxidized triacylglycerol oligomers, and oxidized triacylglycerol monomers significantly increased in all these oils, their increased percentages were much less in CSO than those in EVOO, indicating that CSO has a greater ability to resist oxidation. This work may be useful for the food oil industry and consumers in helping to choose the correct oil and to decide on the useful lifetime of the oil.
