Vertical infusion(self-emptying)bags used for Intravenous infusion are typically obtained by moulding a soft envelope of polypropylene.In normal conditions a continuous flow of liquid can be obtained with no need to u...Vertical infusion(self-emptying)bags used for Intravenous infusion are typically obtained by moulding a soft envelope of polypropylene.In normal conditions a continuous flow of liquid can be obtained with no need to use a pump.In the present study,the relationship between air pressure effects and the drug drip rate have been investigated experimentally and numerically.After determining relevant experimental data about the descending height of liquid level,the dropping speed and pressure,the ordinary least square method and MATLAB have been used to reconstruct the related variation and interrelation laws.Numerical simulations have been performed to determine the best gas-liquid volume ratio and improve the overall performances of these bags.According to these results,that the biggest effect on the drip rate is produced by the diameters of the used needles.展开更多
A field experiment was carried out to investigate the effects of different emitter discharge rates under drip irrigation on soil salinity distribution and cotton yield in an extreme arid region of Tarim River catchmen...A field experiment was carried out to investigate the effects of different emitter discharge rates under drip irrigation on soil salinity distribution and cotton yield in an extreme arid region of Tarim River catchment in Northwest China. Four treatments of emitter discharge rates, i.e. 1.8, 2.2, 2.6 and 3.2 L/h, were designed under drip irrigation with plastic mulch in this paper. The salt distribution in the range of 70-cm horizontal distance and 100-cm vertical distance from the emitter was measured and analyzed during the cotton growing season. The soil salinity is expressed in terms of electrical conductivity （dS/m） of the saturated soil extract （ECe）, which was measured using Time Domain Reflector （TDR） 20 times a year, including 5 irrigation events and 4 measured times before/after an irrigation event. All the treatments were repeated 3 times. The groundwater depth was observed by SEBA MDS Dipper 3 automatically at three experimental sites. The results showed that the order of reduction in averaged soil salinity was 2.6 L/h 〉 2.2 L/h 〉 1.8 L/h 〉 3.2 L/h after the completion of irrigation for the 3-year cotton growing season. Therefore, the choice of emitter discharge rate is considerably important in arid silt loam. Usually, the ideal emitter discharge rate is 2.4-3.0 L/h for soil desalinization with plastic mulch, which is advisable mainly because of the favorable salt leaching of silt loam and the climatic conditions in the studied arid area. Maximum cotton yield was achieved at the emitter discharge rate of 2.6 L/h under drip irrigation with plastic mulch in silty soil at the study site. Hence, the emitter discharge rate of 2.6 L/h is recommended for drip irrigation with plastiic mulch applied in silty soil in arid regions.展开更多
旨在探明水稻在膜下滴灌下根系形态、构型、氮利用效率变化及其与分形维数的关系。于2021—2022年,以氮高效品种(T-43)和氮低效品种(垦-26)为材料,设置滴灌(drip irrigation,DI)、淹灌(flooding irrigation,FI)2种方式与4种施氮水平(0、...旨在探明水稻在膜下滴灌下根系形态、构型、氮利用效率变化及其与分形维数的关系。于2021—2022年,以氮高效品种(T-43)和氮低效品种(垦-26)为材料,设置滴灌(drip irrigation,DI)、淹灌(flooding irrigation,FI)2种方式与4种施氮水平(0、150、300和450 kg hm^(–2))的盆栽试验。基于盒维数法结合根系图像分形分析程序计算根系形态的分形维数和分形丰度,研究滴灌及施氮对水稻产量、氮素利用效率、根系形态、构型、分形维数、分形丰度的影响。结果表明,(1)在相同施氮水平下,与淹灌相比,滴灌处理下T-43和垦-26细根百分比、根长密度(root length density,RLD)β值、氮肥农学利用效率(nitrogen agronomic efficiency,NAE)显著提高(分别为6.8%~14.5%和9.9%~17.2%、0.65%~5.45%和0.32%~3.43%、12.1%~22.4%和12.2%~20.5%);>0.5 mm RLD、0~40 cm土层表面积密度(surface area density,SAD)和根体积密度(RLD)、分形维数(fractal dimension,FD)、分形丰度(fractal abundance,FA)显著降低,造成产量降低(3.8%~37.4%和7.6%~48.3%)。(2)滴灌模式下,施氮显著提高了水稻根系FD和FA,T-43在施氮量为300 kg hm^(–2)时,FD和FA最高(分别为1.55和14.07);垦-26在施氮量为450 kg hm^(–2)时最高(分别为1.62和14.78)。(3)相关分析表明,FD、FA与直径0.1~0.3 mm RLD、0~10 cm土层根长和根质量密度、产量、氮素稻谷生产效率呈显著正相关,与30~40 cm土层表面积密度呈显著负相关。因此,在滴灌条件下,氮高效品种“T-43”配施300 kg hm^(–2)氮肥,能够增加细根根长密度比例,优化表层根系形态分布,提高根系分形维数和丰度,进而实现滴灌水稻产量和氮肥利用效率协同提高。展开更多
基金This article belongs to the project of“The University Synergy Innovation Program of Anhui Province(GXXT-2019-004)”“Teaching Research Project of Anhui Education Department(2019jyxm0229)”.
文摘Vertical infusion(self-emptying)bags used for Intravenous infusion are typically obtained by moulding a soft envelope of polypropylene.In normal conditions a continuous flow of liquid can be obtained with no need to use a pump.In the present study,the relationship between air pressure effects and the drug drip rate have been investigated experimentally and numerically.After determining relevant experimental data about the descending height of liquid level,the dropping speed and pressure,the ordinary least square method and MATLAB have been used to reconstruct the related variation and interrelation laws.Numerical simulations have been performed to determine the best gas-liquid volume ratio and improve the overall performances of these bags.According to these results,that the biggest effect on the drip rate is produced by the diameters of the used needles.
基金supported by the National Basic Research Program of China (2009CB421302)the National Natural Science Foundation of China (41071026,51069017)
文摘A field experiment was carried out to investigate the effects of different emitter discharge rates under drip irrigation on soil salinity distribution and cotton yield in an extreme arid region of Tarim River catchment in Northwest China. Four treatments of emitter discharge rates, i.e. 1.8, 2.2, 2.6 and 3.2 L/h, were designed under drip irrigation with plastic mulch in this paper. The salt distribution in the range of 70-cm horizontal distance and 100-cm vertical distance from the emitter was measured and analyzed during the cotton growing season. The soil salinity is expressed in terms of electrical conductivity （dS/m） of the saturated soil extract （ECe）, which was measured using Time Domain Reflector （TDR） 20 times a year, including 5 irrigation events and 4 measured times before/after an irrigation event. All the treatments were repeated 3 times. The groundwater depth was observed by SEBA MDS Dipper 3 automatically at three experimental sites. The results showed that the order of reduction in averaged soil salinity was 2.6 L/h 〉 2.2 L/h 〉 1.8 L/h 〉 3.2 L/h after the completion of irrigation for the 3-year cotton growing season. Therefore, the choice of emitter discharge rate is considerably important in arid silt loam. Usually, the ideal emitter discharge rate is 2.4-3.0 L/h for soil desalinization with plastic mulch, which is advisable mainly because of the favorable salt leaching of silt loam and the climatic conditions in the studied arid area. Maximum cotton yield was achieved at the emitter discharge rate of 2.6 L/h under drip irrigation with plastic mulch in silty soil at the study site. Hence, the emitter discharge rate of 2.6 L/h is recommended for drip irrigation with plastiic mulch applied in silty soil in arid regions.
文摘旨在探明水稻在膜下滴灌下根系形态、构型、氮利用效率变化及其与分形维数的关系。于2021—2022年,以氮高效品种(T-43)和氮低效品种(垦-26)为材料,设置滴灌(drip irrigation,DI)、淹灌(flooding irrigation,FI)2种方式与4种施氮水平(0、150、300和450 kg hm^(–2))的盆栽试验。基于盒维数法结合根系图像分形分析程序计算根系形态的分形维数和分形丰度,研究滴灌及施氮对水稻产量、氮素利用效率、根系形态、构型、分形维数、分形丰度的影响。结果表明,(1)在相同施氮水平下,与淹灌相比,滴灌处理下T-43和垦-26细根百分比、根长密度(root length density,RLD)β值、氮肥农学利用效率(nitrogen agronomic efficiency,NAE)显著提高(分别为6.8%~14.5%和9.9%~17.2%、0.65%~5.45%和0.32%~3.43%、12.1%~22.4%和12.2%~20.5%);>0.5 mm RLD、0~40 cm土层表面积密度(surface area density,SAD)和根体积密度(RLD)、分形维数(fractal dimension,FD)、分形丰度(fractal abundance,FA)显著降低,造成产量降低(3.8%~37.4%和7.6%~48.3%)。(2)滴灌模式下,施氮显著提高了水稻根系FD和FA,T-43在施氮量为300 kg hm^(–2)时,FD和FA最高(分别为1.55和14.07);垦-26在施氮量为450 kg hm^(–2)时最高(分别为1.62和14.78)。(3)相关分析表明,FD、FA与直径0.1~0.3 mm RLD、0~10 cm土层根长和根质量密度、产量、氮素稻谷生产效率呈显著正相关,与30~40 cm土层表面积密度呈显著负相关。因此,在滴灌条件下,氮高效品种“T-43”配施300 kg hm^(–2)氮肥,能够增加细根根长密度比例,优化表层根系形态分布,提高根系分形维数和丰度,进而实现滴灌水稻产量和氮肥利用效率协同提高。
