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不同叶片卷曲度杂交水稻的光合特性比较 被引量:49
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作者 朱德峰 林贤青 曹卫星 《作物学报》 CAS CSCD 北大核心 2001年第3期329-333,共5页
在田间条件下研究了叶片卷曲度不同的 6个代表性杂交水稻组合在开花期和花后 2 0天上部 3张叶片的卷曲度和剑叶叶片近轴面 (上表面 )、远轴面 (下表面 )光合强度、叶片角度、挺直度、群体消光系数的关系。结果表明 ,剑叶卷曲度高的组合... 在田间条件下研究了叶片卷曲度不同的 6个代表性杂交水稻组合在开花期和花后 2 0天上部 3张叶片的卷曲度和剑叶叶片近轴面 (上表面 )、远轴面 (下表面 )光合强度、叶片角度、挺直度、群体消光系数的关系。结果表明 ,剑叶卷曲度高的组合叶片卷曲度达 4 4 %~ 4 7% ,中等的组合为 15%~ 16% ,低的组合为 10 %~ 11%。高叶片卷曲度组合的剑叶上表面 ,由于受自身叶片遮光的影响而使光合强度低于下表面 ,下表面与上表面光合强度比为 1.19~ 1.32 ,中等叶片卷曲度组合为 0 .90~ 1.0 2 ,低叶片卷曲度组合为 0 .82~ 0 .85。与叶片卷曲度低的组合相比 ,叶片卷曲度高和中等的组合具有较小的叶片角度、较高的叶片挺直度和较低的消光系数。 展开更多
关键词 水稻 叶片卷曲 光合作用 叶片角 叶片挺直度
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热处理冷却过程对55钢尺带组织和性能的影响 被引量:2
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作者 王保华 《热加工工艺》 北大核心 2019年第22期124-126,131,共4页
研究了冷却板长度和冷却水温对55钢尺带力学性能的影响。结果表明:随着冷却板长度从200 mm增加到400 mm,尺带硬度从497 HV增加到583 HV,然后保持在此水平上,直线度从3.6 mm增加到最大值6.4 mm,呈单调增加变化;随着冷却水温从10°C... 研究了冷却板长度和冷却水温对55钢尺带力学性能的影响。结果表明:随着冷却板长度从200 mm增加到400 mm,尺带硬度从497 HV增加到583 HV,然后保持在此水平上,直线度从3.6 mm增加到最大值6.4 mm,呈单调增加变化;随着冷却水温从10°C升高到30°C,挺直度从1305 mm降到最小值825 mm,呈单调下降变化,疲劳寿命先增加后减少,呈抛物线状变化;当冷却板长度为300 mm、冷却水温为20 C时,尺带的硬度为581 HV,直线度为4.2 mm,疲劳寿命为6541次,挺直度为1238 mm,此时,显微组织为回火马氏体组织,无网状铁素体,为最佳的热处理工艺。 展开更多
关键词 尺带 冷却板 挺直度 水温 网状铁素体
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高频脉冲TIG焊电源 被引量:2
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作者 马淼 黄鹏飞 卢振洋 《电焊机》 2015年第10期34-37,共4页
采用两套斩波电路输出端并联的方式,设计了一台高频直流脉冲TIG焊电源。该电源可以输出不同频率、不同占空比、具有陡峭上升沿和下降沿的脉冲电流,并且基值电流和峰值电流可以独立调节。对比了常规直流TIG焊和高频直流脉冲TIG焊电弧的... 采用两套斩波电路输出端并联的方式,设计了一台高频直流脉冲TIG焊电源。该电源可以输出不同频率、不同占空比、具有陡峭上升沿和下降沿的脉冲电流,并且基值电流和峰值电流可以独立调节。对比了常规直流TIG焊和高频直流脉冲TIG焊电弧的挺直度,结果表明,在电流平均值相同的情况下,无论在高速焊接还是V型坡口焊接中,高频电弧都具有良好的挺直度,焊接工艺性能明显优于普通直流TIG焊。 展开更多
关键词 高频脉冲 TIG焊 电弧挺直度
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热处理工艺对55钢尺带力学性能的影响 被引量:1
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作者 宋凤祥 《热加工工艺》 北大核心 2021年第6期127-129,共3页
研究了淬火温度和运行速度对55钢尺带力学性能的影响。结果表明:在840~920℃,随着淬火温度的增加,硬度和挺直度均逐渐增大。当尺带运行速度在150~190 mm/s时,随着运行速度的增加,抗拉强度和疲劳寿命均呈先增加后降低的变化趋势。当尺带... 研究了淬火温度和运行速度对55钢尺带力学性能的影响。结果表明:在840~920℃,随着淬火温度的增加,硬度和挺直度均逐渐增大。当尺带运行速度在150~190 mm/s时,随着运行速度的增加,抗拉强度和疲劳寿命均呈先增加后降低的变化趋势。当尺带运行速度为180 mm/s、在炉内900℃温度下淬火时,硬度为579 HV0.2,挺直度为1290 mm,抗拉强度为2423 N/mm2,抽拉试验疲劳寿命为6758次。此淬火温度和运行速度为最佳热处理工艺,此时,显微组织是马氏体。 展开更多
关键词 尺带 55钢 挺直度 抗拉强 淬火温
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一个新水稻内卷叶突变体的杂优组合生物学效应
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作者 张致力 龚晓平 +6 位作者 况晓明 罗挺 李加胜 赵许兵 赵冰峰 曾胜 杨霞 《西南农业学报》 CSCD 北大核心 2015年第4期1428-1432,共5页
以生育中后期叶片适度内卷叶和平展叶组合为材料,研究了水稻适度内卷叶突变体RL(t)杂优组合的生物学效应。结果表明:1RL(t)杂优组合与平展叶组合生育前期生长叶态相似,均为平展叶且叶基角较大;2RL(t)杂优组合生育中后期叶片气孔导度、胞... 以生育中后期叶片适度内卷叶和平展叶组合为材料,研究了水稻适度内卷叶突变体RL(t)杂优组合的生物学效应。结果表明:1RL(t)杂优组合与平展叶组合生育前期生长叶态相似,均为平展叶且叶基角较大;2RL(t)杂优组合生育中后期叶片气孔导度、胞间CO2浓度、蒸腾速率显著高于平展叶组合,其光合速率较平展叶组合也有所提高,为其提高单位面积产量奠定了基础;3RL(t)杂优组合在群体中部透光率显著高于平展叶组合,改善了群体中下部叶片受光条件,从而提高了光能利用率;4RL(t)杂优组合在不同密度下产量构成因子自我调控能力显著增强,尤其在高密度下,具有较高的容穗量,并能较好地保持大穗特点。本研究为适度内卷叶应用于水稻高产育种提供理论依据。 展开更多
关键词 水稻 内卷 挺直度 光合速率 透光率
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一个新的水稻内卷叶突变体的光合生理效应
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作者 龚晓平 况晓明 +6 位作者 罗挺 李加胜 赵许兵 赵冰峰 曾胜 杨霞 张致力 《安徽农业科学》 CAS 2014年第23期7743-7745,7747,共4页
[目的]明确水稻叶片前平后卷的主要生物学效应,为RL(t)在水稻育种中的应用提供理论依据。[方法]在水稻杂交后代材料中发现一个新的内卷叶突变材料,暂时命名为RL(t),研究了RL(t)与平展叶姊妹系0731-3-1-1B在叶片受光姿态、光合效率及细... [目的]明确水稻叶片前平后卷的主要生物学效应,为RL(t)在水稻育种中的应用提供理论依据。[方法]在水稻杂交后代材料中发现一个新的内卷叶突变材料,暂时命名为RL(t),研究了RL(t)与平展叶姊妹系0731-3-1-1B在叶片受光姿态、光合效率及细胞组织结构的差异。[结果]RL(t)较平展叶姊妹保持系三片功能叶明显表现出卷曲度大、挺直度高、叶基角小、披垂角小,相应地,提高了卷叶保持系群体各层尤其上部和中部的透光率;三片功能叶的气孔导度、胞间CO2浓度和剑叶、倒二叶的蒸腾速率显著高于平展叶姊妹保持系,从而提高了RL(t)剑叶、倒二叶的光合速率;由于卷叶保持系部分泡状细胞适度萎缩变小,导致叶片内向卷曲。[结论]该研究为内卷叶性状应用于水稻高产育种提供了理论依据。 展开更多
关键词 水稻 叶片卷曲 挺直度 光合速率 透光率
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Biological Effects in Heterotic Combination with Novel Adaxially-rolling Character in Rice(Oryza sativa L.) 被引量:1
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作者 龚晓平 况晓明 +5 位作者 罗挺 李加胜 赵许兵 赵冰峰 曾胜 张致力 《Agricultural Science & Technology》 CAS 2015年第11期2504-2508,2512,共6页
Taking the heterotic combinations which respectively had moderately-rolled leaves and flat leaves at middle and later stages as tested materials, the biological effects in the heterotic combination of the moderately-r... Taking the heterotic combinations which respectively had moderately-rolled leaves and flat leaves at middle and later stages as tested materials, the biological effects in the heterotic combination of the moderately-roiling leaf mutant RL(f) were studied. The results showed that (i) there was insignificant difference between the leaf morphological characteristics of the RL(t) and fiat leaf heterotic ombinations at early growth stage in that beth of them had fiat leaves and relatively big basic leaf angles; (it) the stomatal conductance, the intercellular CO2 concentration, transpira- tion rate and photosynthetic rate of the three top leaves of the RL(t) heterotic com- bination were significantly higher than those of the flat leaf heterotic combination at middle and later stages, which laid the foundation for increasing the yield per unit area; (iii) the light transmittance of the RL(f) heterotic combination in population at the middle part was higher than that of flat leaf heterotic combination, resulted in improved light interception condition at middle and lower parts of the population and increased the utilization efficiency of tight energy; and (iv) this research revealed that the RL(t) heterotic combination could not only maintain a larger amount of the effective panicles but also could present large-panicle characteristic, especially in high-density condition, and also the ability of adjusting yield components the RL(f) heterotic combination was significantly increased under different densities. This study would provide a theoretical basis for the principle of high-yielding breeding with the application of the moderately-rolling leaf mutant in rice. 展开更多
关键词 RICE Moderately rolling STRAIGHTNESS Photosynthetic rate Ught transmittance
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Study on Photosynthetic and Physiological Effects of a Novel Adaxially-Rolled Character in Rice (Oryza sativa L.)
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作者 龚晓平 况晓明 +6 位作者 罗挺 李加胜 赵许兵 赵冰峰 曾胜 杨霞 张致力 《Agricultural Science & Technology》 CAS 2015年第3期431-434,441,共5页
Objective] The main biological effects of leaf rol ing of rice was studied to provide the theoretical basis for the application of RL (t) in the breeding of the rice. [Method] A rice mutant with adaxial y-rol ed lea... Objective] The main biological effects of leaf rol ing of rice was studied to provide the theoretical basis for the application of RL (t) in the breeding of the rice. [Method] A rice mutant with adaxial y-rol ed leaf was found in breeding, temporarily named as RL (t). The differences were researched in which light interception struc-ture, light transmission photosynthetic efficiency and cel ular structure comparison between RL (t) and its sister lines that had flat leaf. [Result] Both leaf rol ing index and leaf erecting index of RL (t) were higher than those in 0731-3-1-1B. However, its basic leaf angle and leaf drooping angle were significantly lower than those in 0731-3-1-1B in upper three leaves, which caused a great raise in the photosynthetic rate on account of the light transmittance of RL (t)’s population were significantly higher than that of 0731-3-1-1B especial y the upper and middle part. The stomata conductance and the intercel ular CO2 concentration of the upper three leaves and transpiration rate of the flag and the second leaf were also significantly higher than that of 0731-3-1-1B. The bul iform cel s became smal er, leading to the rol ing up of leaves. [Conclusion] The study provided a theoretical basis for the principle of high-yielding breeding with the application of the adaxial y-rol ed leaf mutant in rice. 展开更多
关键词 RICE Leaf rolling index Leaf erecting-index Photosynthetic rate Lighttransmittance
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