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71.
Bowen Yan Haoyu Zheng Yuwei Sang Yan Wang Jian Sun Fengcheng Li Jiayu Wang Xiaoxue Wang 《International journal of molecular sciences》2022,23(16)
Lesion mimic mutants are an ideal model system for elucidating the molecular mechanisms of programmed cell death and defense responses in rice. In this study, we identified a lesion mimic mutant termed miner infection like 1-1 (mil1-1). The mil1-1 exhibited lesions on the leaves during development, and the chloroplasts of mil1-1 leaves were disrupted. Reactive oxygen species were found to accumulate in mil1-1 leaves. Cell death and DNA fragmentation were observed in mil1-1 leaves, indicating that the cells in the spots of mil1-1 leaves experienced programmed cell death. Most agronomic traits decreased in mil1-1, suggesting that the growth retardation in mil1-1 caused reduced per-plant grain yield. However, the mutation of MIL1 activated the expression of pathogen response genes and enhanced resistance to bacterial blight. The MIL1 gene was cloned using the positional cloning approach. A missense mutation 751 bp downstream of ATG was found in mil1-1. The defects of mil1-1 were able to be rescued by delivering a wild-type MIL1 gene into mil1-1. MIL1 encoded hydroperoxide lyase 3 (OsHPL3), and the expression of OsHPL3 was induced via hormone and abiotic stresses. Our findings provide insights into the roles of MIL1 in regulating programmed cell death, development, yield, and defense responses in rice. 相似文献
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73.
Junzhe Li Shao-hua Luo Yang Sun Jiayu Li Jun Zhang Ting-Feng Yi 《Ceramics International》2019,45(4):4849-4856
Sodium-substituted LiMnPO4/C/reduced graphene oxide (LNMP@rGO) was synthesized in this study via freeze drying and carbon thermal reduction method with graphene oxide as carbon source. Sodium ion doping is optimized and rGO effects are evaluated by XRD, SEM, TEM, BET, Raman, and electrochemical performance measurements. Well-distributed nanoparticles with average size of ~50?nm are evenly distributed on the surface or intercalation between rGO layers, resulting in a porous ion/electronic conductive network. Compared to 122.3?mA?h?g?1 in unmodified LNMP, the best LNMP@rGO (20?mg rGO) exhibits an excellent initial discharge capacity of 150.4?mA?h?g?1 at 0.05?C at 122.9% of the initial capacity. The capacity retention rate is 95.8% of the initial capacity after 100 cycles at 1?C. Capacity of 101.2?mA?h?g?1 is preserved even at rates as high as 10?C. 相似文献
74.
用X射线衍射、差示扫描量热法和热膨胀系数测试研究了BaO-Al2O3-SiO2(BAS)系微晶玻璃的不同晶化时间对其相组成和热膨胀系数的影响.结果表明:在850 ℃,BAS玻璃快速晶化析出六方钡长石;随着晶化时间的延长,六方钡长石逐渐向单斜钡长石转变;当晶化时间为24 h时,六方钡长石完全转变为单斜钡长石.微晶玻璃的相组成与热膨胀系数的关系近似满足两相模型,可通过改变晶化时间来控制相组成,方便的获得热膨胀系数在(4~8.75)×10-6/℃范围内可调整的BAS系微晶玻璃. 相似文献
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76.
为研究ns脉冲激励下的气体放电现象,近年来基于高能电子逃逸引导放电发展的相关研究受到了广泛关注。利用上升沿15ns,半高宽30-40ns的重复频率ns脉冲激励极不均匀电场下大气压空气放电,将实验测量和理论计算相结合,研究了基于高能电子逃逸击穿的ns脉冲气体放电特性。实验结果表明高重复频率下仍可获得大面积均匀的弥散放电,放电中存在能量范围为10-130keV的X射线。理论计算结果表明施加120kV负极性脉冲条件下电场强度最高可达718kV/cm,高于大气压空气中产生逃逸电子的场强阈值,放电中X射线与逃逸电子有关。进一步对从理论上对ns脉冲气体放电特性进行探索,极不均匀电场下的场致发射为放电提供初始电子,其中能量较高的电子在气隙运动过程中发生逃逸,与气体分子碰撞产生二次电子,并辐射出X射线。逃逸电子与X射线共同作用,有利于获得大面积的弥散放电。 相似文献
77.
Under the "carbon peak and carbon neutrality" ("dual carbon") goals, China's landscape of city gas market is reshaping with the advancement of oil and gas system reform, so it is of significance to study the transformation and development of city gas companies under the new situation. In this paper, from the perspectives of macro trends, policies and regulations, and market structure, the situation faced by city gas companies in China and their exploration and practice during the process of transformation are studied, with common problems analyzed as well. The results show that in an environment that offers opportunities and challenges (e.g. peak gas demand, development of emerging energy technologies, toughening industry supervision, and innovative policies), it is a general trend for city gas companies to transform and upgrade their business. Exploration efforts that have been made by these companies include extending the industrial chain based on their main operations, developing integrated energy business based on natural gas, accelerating business digitization, expanding emerging energy technologies and formats, as well as building and upgrading their core scientific research capabilities. However, they are still restricted by their traditional operational thinking, inadequate strategic development planning, and insufficient support for internal mechanism and systems. It is hence suggested that the positioning of the city gas sector and companies should be clarified, and strategic development plans should be mapped out carefully. More efforts are needed to tap users' demand for multi-category energy products, diversify and expand business range, and accelerate digital transformation. In addition, sustained efforts are required to improve the mechanism and systems, promote transformation and development, and accelerate the construction of an appropriate ecology. 相似文献
78.
超特高压交流输电系统是中国远距离、大容量输送电能的重要方式。为了提升超特高压输电线路的输送能力,在交流长线路两侧常会加装串联补偿装置等补偿设备。然而,实际工程中却发现,在装设补偿设备后,由于线路的电流互感器和电压互感器安装点分别布置在补偿装置两侧,传统的线路输送功率计算方法无法准确获取线路传输的功率,进而导致变电站监控系统判定母线功率不平衡的状况时有发生。为了解决上述问题,基于线路潮流计算方法,定量分析了补偿装置的引入引发交流线路功率计算不准的原因,推导了功率修正算法。简单算例及西部某变电站的500 k V输电线路算例验证了算法的准确可靠。该方法简单易行,易于在超特高压变电站中实施应用。 相似文献
79.
为了克服传统的早期微小故障诊断方法不能区分多个不同时刻发生故障的不足,提出一种将深度学习和PCA相结合的方法实现微小缓变故障早期诊断及寿命预测。 对采集的数据进行深度学习实现逐层特征抽取,学习早期微小故障特征,建立微小缓变故障早期诊断模型,结合PCA方法将深度学习所抽取的高维故障特征向量集成为一个故障特征变量,根据历史故障数据特征变量演化规律定义数据驱动的故障演变标尺,并通过指数型非线性拟合方法建立寿命预测模型。 选取TE平台数据进行算法有效性检验,并与其他算法对比,从而验证了所提出算法的有效性。 相似文献
80.
针对鄂尔多斯盆地南部上古生界不同类型烃源岩生烃贡献不明确的问题,利用生烃动力学研究方法,考虑不同岩性烃源有机质品质差异、岩石物性、吸附能力等因素,评价了鄂尔多斯盆地南部上古生界煤岩和炭质泥岩的生烃特征。综合煤岩、炭质泥岩在南部的厚度分布,绘制了鄂尔多斯盆地南部上古生界煤岩、炭质泥岩生烃强度、排烃强度图。结果显示,鄂尔多斯盆地南部上古生界在煤层分布局限的情况下,炭质泥岩是主力烃源岩,这与前人仅根据地球化学特征参数而得出南部煤岩为主力烃源岩的认识有很大不同。相关认识对今后盆地南部下古生界天然气勘探开发具有重要的指导意义。 相似文献