为探究孕穗期冷水灌溉下粳稻籽粒灌浆过程中的干物质、氮素形成积累规律及氮代谢关键酶调控效应，以东农428和松粳10为材料，设置6个冷水灌溉持续时间（0、3、6、9、12和15 d），分析孕穗期冷水灌溉对寒地粳稻籽粒灌浆过程中的干物质、...为探究孕穗期冷水灌溉下粳稻籽粒灌浆过程中的干物质、氮素形成积累规律及氮代谢关键酶调控效应，以东农428和松粳10为材料，设置6个冷水灌溉持续时间（0、3、6、9、12和15 d），分析孕穗期冷水灌溉对寒地粳稻籽粒灌浆过程中的干物质、氮素积累及氮代谢关键酶活性的影响。结果表明，与对照相比，孕穗期冷水灌溉下，寒地粳稻产量及籽粒干物质积累量的变化规律一致，冷水灌溉持续时间越长，产量及籽粒干物质积累量降幅越大。冷水灌溉下，寒地粳稻籽粒干物质积累量降低，除与籽粒干物质最大相对积累速率降低有关外，还与结实率降低、有效穗数和每穗总粒数减少有关。冷水灌溉可提高寒地粳稻籽粒全氮、蛋白氮、成熟期籽粒粗蛋白含量及灌浆前期籽粒谷氨酰胺合成酶（GS）活性。冷水灌溉6 d 可显著提高籽粒谷草转氨酶（GOT）及谷丙转氨酶（GPT）活性，冷水灌溉9~15 d 可显著降低其活性。短期冷水灌溉下（3~6 d），寒地粳稻通过增强有机氮同化过程，促进蛋白质合成，使籽粒氮素含量增加；长期冷水灌溉下（9~15 d），籽粒有机氮同化过程受到抑制，影响氨基酸和蛋白质的合成，最终导致籽粒氮素增幅下降。籽粒全氮、蛋白氮和淀粉颗粒态结合蛋白是不同耐冷性品种响应冷水胁迫的差异产物，其含量可作为耐冷性鉴定的指标。展开更多
Avoiding the folding defect and improving the die filling capability in the transitional region are desired in isothermal local loading forming of a large-scale Ti-alloy rib-web component（LTRC）. To achieve a high-pr...Avoiding the folding defect and improving the die filling capability in the transitional region are desired in isothermal local loading forming of a large-scale Ti-alloy rib-web component（LTRC）. To achieve a high-precision LTRC, the folding evolution and die filling process in the transitional region were investigated by 3 D finite element simulation and experiment using an equal-thickness billet（ETB）. It is found that the initial volume distribution in the second-loading region can greatly affect the amount of material transferred into the first-loading region during the second-loading step, and thus lead to the folding defect. Besides, an improper initial volume distribution results in non-concurrent die filling in the cavities of ribs after the second-loading step, and then causes die underfilling. To this end, an unequal-thickness billet（UTB） was employed with the initial volume distribution optimized by the response surface method（RSM）. For a certain eigenstructure, the critical value of the percentage of transferred material determined by the ETB was taken as a constraint condition for avoiding the folding defect in the UTB optimization process,and the die underfilling rate was considered as the optimization objective. Then, based on the RSM models of the percentage of transferred material and the die underfilling rate, non-folding parameter combinations and optimum die filling were achieved. Lastly, an optimized UTB was obtained and verified by the simulation and experiment.展开更多
Filling techniques are often used in the restoration of images.Yet the existing filling technique approaches either have high computational costs or present problems such as filling holes redundantly.This paper propos...Filling techniques are often used in the restoration of images.Yet the existing filling technique approaches either have high computational costs or present problems such as filling holes redundantly.This paper proposes a novel algorithm for filling holes and regions of the images.The proposed algorithm combines the advantages of both the parity-check filling approach and the region-growing inpainting technique.Pairing points of the region’s boundary are used to search and to fill the region.The scanning range of the filling method is within the target regions.The proposed method does not require additional working memory or assistant colors,and it can correctly fill any complex contours.Experimental results show that,compared to other approaches,the proposed algorithm fills regions faster and with lower computational cost.展开更多
文摘为探究孕穗期冷水灌溉下粳稻籽粒灌浆过程中的干物质、氮素形成积累规律及氮代谢关键酶调控效应，以东农428和松粳10为材料，设置6个冷水灌溉持续时间（0、3、6、9、12和15 d），分析孕穗期冷水灌溉对寒地粳稻籽粒灌浆过程中的干物质、氮素积累及氮代谢关键酶活性的影响。结果表明，与对照相比，孕穗期冷水灌溉下，寒地粳稻产量及籽粒干物质积累量的变化规律一致，冷水灌溉持续时间越长，产量及籽粒干物质积累量降幅越大。冷水灌溉下，寒地粳稻籽粒干物质积累量降低，除与籽粒干物质最大相对积累速率降低有关外，还与结实率降低、有效穗数和每穗总粒数减少有关。冷水灌溉可提高寒地粳稻籽粒全氮、蛋白氮、成熟期籽粒粗蛋白含量及灌浆前期籽粒谷氨酰胺合成酶（GS）活性。冷水灌溉6 d 可显著提高籽粒谷草转氨酶（GOT）及谷丙转氨酶（GPT）活性，冷水灌溉9~15 d 可显著降低其活性。短期冷水灌溉下（3~6 d），寒地粳稻通过增强有机氮同化过程，促进蛋白质合成，使籽粒氮素含量增加；长期冷水灌溉下（9~15 d），籽粒有机氮同化过程受到抑制，影响氨基酸和蛋白质的合成，最终导致籽粒氮素增幅下降。籽粒全氮、蛋白氮和淀粉颗粒态结合蛋白是不同耐冷性品种响应冷水胁迫的差异产物，其含量可作为耐冷性鉴定的指标。
基金supports of the National Natural Science Foundation of China (No. 51575449)Research Fund of the State Key Laboratory of Solidification Processing (NWPU) of China (No. 104-QP2014)+1 种基金the 111 Project (No. B08040)the Fundamental Research Funds for the Central Universities (3102015AX004)
文摘Avoiding the folding defect and improving the die filling capability in the transitional region are desired in isothermal local loading forming of a large-scale Ti-alloy rib-web component（LTRC）. To achieve a high-precision LTRC, the folding evolution and die filling process in the transitional region were investigated by 3 D finite element simulation and experiment using an equal-thickness billet（ETB）. It is found that the initial volume distribution in the second-loading region can greatly affect the amount of material transferred into the first-loading region during the second-loading step, and thus lead to the folding defect. Besides, an improper initial volume distribution results in non-concurrent die filling in the cavities of ribs after the second-loading step, and then causes die underfilling. To this end, an unequal-thickness billet（UTB） was employed with the initial volume distribution optimized by the response surface method（RSM）. For a certain eigenstructure, the critical value of the percentage of transferred material determined by the ETB was taken as a constraint condition for avoiding the folding defect in the UTB optimization process,and the die underfilling rate was considered as the optimization objective. Then, based on the RSM models of the percentage of transferred material and the die underfilling rate, non-folding parameter combinations and optimum die filling were achieved. Lastly, an optimized UTB was obtained and verified by the simulation and experiment.
基金The research is jointly supported by the National Natural Science Foundation of China No.61561035by Ukrainian government project No.0117U007177the Slovak Research and Development Agency project number APVV-18-0214.
文摘Filling techniques are often used in the restoration of images.Yet the existing filling technique approaches either have high computational costs or present problems such as filling holes redundantly.This paper proposes a novel algorithm for filling holes and regions of the images.The proposed algorithm combines the advantages of both the parity-check filling approach and the region-growing inpainting technique.Pairing points of the region’s boundary are used to search and to fill the region.The scanning range of the filling method is within the target regions.The proposed method does not require additional working memory or assistant colors,and it can correctly fill any complex contours.Experimental results show that,compared to other approaches,the proposed algorithm fills regions faster and with lower computational cost.
