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31.
Two new different metal-organic frameworks (MOFs)[Ba(L1)(H2O)2]n·nH2O (MOF 1) and[Ba(L2)(-H2O)2]n·0.5nDMF·0.5nH2O (MOF 2) were yielded by the assembly of oxygen... 相似文献
32.
Weizeng Lv Xue He Haojuan Guo Haibin Lan Yanqing Jiao Le Li Yanhao Lian Zhiqiang Wang Zeyu Xin Yongzhe Ren Tongbao Lin 《International journal of molecular sciences》2022,23(14)
Excessive input of nitrogen fertilizer not only causes a great waste of resources but brings about a series of ecological and environmental problems. Although Small Auxin Up-regulated RNAs (SAURs) participate in diverse biological processes, the function of SAURs in the nitrogen starvation response has not been well-studied. Here, we identified 308 TaSAURs in wheat and divided them into 10 subfamilies. The promoter regions of most TaSAURs contain hormone responsive elements, and their expression levels change under the treatment of different hormones, such as IAA, MeJA, and ABA. Interestingly, overexpression of one of the TaSAUR family members, a nitrogen starvation responsive gene, TaSAUR66-5B, can promote the growth of Arabidopsis and wheat roots. In addition, overexpression of TaSAUR66-5B in Arabidopsis up-regulates the expression levels of auxin biosynthesis related genes, suggesting that overexpression TaSAUR66-5B may promote root growth by increasing the biosynthesis of auxin. Furthermore, overexpression of TaSAUR66-5B in wheat can increase the biomass and grain yields of transgenic plants, as well as the nitrogen concentration and accumulation of both shoots and grains, especially under low nitrogen conditions. This study provides important genomic information of the TaSAUR gene family and lays a foundation for elucidating the functions of TaSAURs in improving nitrogen utilization efficiency in wheat. 相似文献
33.
Chunyang Jiao Kaixiang Li Yixin Zuo Junqing Gong Zhujuan Guo Yingbai Shen 《International journal of molecular sciences》2022,23(14)
Jasmonic acid (JA) is an important hormone that functions in plant defense. cam1 and wrky53 mutants were more resistant to Spodoptera littoralis than in the wild-type (WT) Arabidopsis group. In addition, JA concentration in cam1 and wrky53 mutants was higher compared with the WT group. To explore how these two proteins affect the resistance of Arabidopsis plants, we used a yeast two-hybrid assay, firefly luciferase complementation imaging assay and in vitro pull-down assay confirming that calmodulin 1 (CAM1) interacted with WRKY53. However, these two proteins separate when calcium concentration increases in Arabidopsis leaf cells. Then, electrophoretic mobility shift assay and luciferase activation assay were used to verify that WRKY53 could bind to lipoxygenases 3 (LOX3) and lipoxygenases 4 (LOX4) gene promoters and negatively regulate gene expression. This study reveals that CAM1 and WRKY53 negatively regulate plant resistance to herbivory by regulating the JA biosynthesis pathway via the dissociation of CAM1-WRKY53, then the released WRKY53 binds to the LOXs promoters to negatively regulate LOXs gene expression. This study reveals WRKY53′s mechanism in insect resistance, a new light on the function of WRKY53. 相似文献
34.
研究了SiN钝化前利用感应耦合等离子体(ICP)对AlGaN/GaN HEMT表面进行NF3等离子体处理对器件性能的影响.结果表明,运用低能量的NF3等离子体处理钝化前的AlGaN/GaN HEMT表面能有效抑制器件电流崩塌,而器件直流及微波小信号特性则未受影响.微波功率测试表明,经过6min NF3等离子体处理的AIGaN/GaN HEMT在2GHz,30V工作电压下达到6.15W/mm的输出功率密度,而未经过处理的器件只达到1.82W/mm的输出功率密度. 相似文献
35.
Felix Kogan Corresponding author Bangjie Yang Guo Wei Pei Zhiyuan Jiao Xianfeng 《International journal of remote sensing》2013,34(11):2325-2336
Weather‐related crop losses have always been a concern for farmers, governments, traders and policy makers for the purpose of balanced food supplies, demands, trade, and distribution of aid to nations in need. Therefore, early crop loss assessment in response to weather fluctuations is an important issue. This paper discusses the utility of Advanced Very High Resolution Radiometer (AVHRR)‐based vegetation health indices as a proxy for modelling corn yield and for early warning of drought‐related losses of agricultural production in China. The indices were tested in Jilin province on corn yield during 1982–2001 using correlation and regression analysis. A strong correlation between corn yield and the vegetation health indices were found during the critical period of corn growth, which starts 2–3 weeks before and 2–3 weeks after corn tassel. Following the results of correlation analysis, several regression equations were constructed where vegetation health indices were used as independent variables. The estimates of corn yield can be carried out well in advance of harvest and the errors of the estimates are 7–10%. The errors become smaller when the estimations are related to losses in corn yield due to drought. 相似文献
36.
比较了冶金机械设备在停电故障下几种事故驱动方式,重点介绍了新兴的EPS(Emergency Power Supply)事故驱动电源,并倾向于采用EPS作为冶金设备的主要事故驱动。 相似文献
37.
<正>为降低牵引架与回转圈的摩擦,徐工生产的平地机都装有耐磨衬垫。图1为平地机回转圈、牵引定位用AB胶粘在牵引架上,在回转圈回转过程中起到保护牵引架和回转圈的作用。平地机工作过程中,由于回转圈与牵引架相对运动时产生的冲击, 相似文献
38.
39.
介绍了一种分布式多元胞集成半导体放电管的结构设计和工艺方法。在保持传统单元胞放电管器件表面总面积和放电管纵向剖面NPNPN五层结构不变的情况下,将放电管发射区等分成2(N+1)2个(N取0,1,2,3,4),构成在基区中心对称的多元胞结构。该结构优化了放电管阴极发射区的分布,使浪涌电流在整个芯片平面上趋于均匀,降低了发射区的热量集中效应;同时增加了电流放大系数,减少了放电管的开通时间。采用镓扩散、玻璃钝化等工艺流程,制作出分布式多元胞集成半导体放电管,解决了单元胞放电管散热不均匀、响应速度慢及可靠性差的问题。雷电波冲击电流测试表明,该结构提高了器件的抗电涌能力,可广泛应用于通信领域的雷电防护。 相似文献
40.
为了兼容众多直放站综合网络监控管理协议,借助C#软件开发平台,采用典型的MVC框架,设计了一种具有统一接口的独立的协议库.该协议库采用多线程发送和接收数据帧及序列存储数据流的方式,通过其统一的协议库处理接口和直放站进行信息交互,处理数据帧的组帧及解析过程.经测试,证明此设计实现了对直放站设备快速有效的监控,具有广阔的应用前景. 相似文献