Plant DNA Methylation: An Epigenetic Mark in Development,Environmental Interactions,and Evolution

DNA methylation is an epigenetic modification of the genome involved in the regulation of gene expression and modulation of chromatin structure. Plant genomes are widely methylated, and the methylation generally occurs on the cytosine bases through the activity of specific enzymes called DNA methyltransferases. On the other hand, methylated DNA can also undergo demethylation through the action of demethylases. The methylation landscape is finely tuned and assumes a pivotal role in plant development and evolution. This review illustrates different molecular aspects of DNA methylation and some plant physiological processes influenced by this epigenetic modification in model species, crops, and ornamental plants such as orchids. In addition, this review aims to describe the relationship between the changes in plant DNA methylation levels and the response to biotic and abiotic stress. Finally, we discuss the possible evolutionary implications and biotechnological applications of DNA methylation.     

GmIAA27 Encodes an AUX/IAA Protein Involved in Dwarfing and Multi-Branching in Soybean

Soybean plant height and branching affect plant architecture and yield potential in soybean. In this study, the mutant dmbn was obtained by treating the cultivar Zhongpin 661 with ethylmethane sulfonate. The dmbn mutant plants were shorter and more branched than the wild type. The genetic analysis showed that the mutant trait was controlled by a semi-dominant gene. The candidate gene was fine-mapped to a 91 kb interval on Chromosome 9 by combining BSA-seq and linkage analysis. Sequence analysis revealed that Glyma.09g193000 encoding an Aux/IAA protein (GmIAA27) was mutated from C to T in the second exon of the coding region, resulting to amino acid substitution of proline to leucine. Overexpression of the mutant type of this gene in Arabidopsis thaliana inhibited apical dominance and promoted lateral branch development. Expression analysis of GmIAA27 and auxin response genes revealed that some GH3 genes were induced. GmIAA27 relies on auxin to interact with TIR1, whereas Gmiaa27 cannot interact with TIR1 owing to the mutation in the degron motif. Identification of this unique gene that controls soybean plant height and branch development provides a basis for investigating the mechanisms regulating soybean plant architecture development.     

火电厂用中水水质问题及改善措施的分析

针对火电厂用于循环冷却水和锅炉补给水的中水水质不稳定的问题,介绍通过改进污水处理阶段的工艺和深度处理必电厂初级阶段中水以提高中水水质的措施,对节能减排、保护环境吴有重要意义.     

吉林省农业水资源与种植结构关系

本文在大量调研的基础上,就吉林省"十一五"期间实现增加粮食产量的发展目标,根据吉林省水资源现状与支持程度,提出进行农业产业结构的调整与优化思路.     

沙角C电厂一次风机故障分析及处理

风机是火电厂的重要辅机,风机工作点偏离最佳经济工况、运行中出现动叶卡瑟、喘振是风机最常见故障,如果处理不当可能导致火电厂事故停炉。通过对沙角C电厂660MW机组轴流式一次风机在运行时出现动叶卡涩、过力矩、液压油温高等一系列问题的分析,采取相应的措施进行处理,从根本上解决了一次风机的故障,对同类型一次风机的故障处理具有参考作用。     

竞价环境下燃煤发电企业降低发电成本的储煤优化模型

未来的发电企业需要通过竞价实现上网,竞价成功的前提是具有低于竞争对手的发电成本。燃煤发电企业每年要消耗大量的物料(燃料、水、油、备品材料),以保证生产连续、稳定、正常地运行,这些物料会形成很大的库存成本。通过对煤炭库存成本最小化的研究,构造了燃煤发电企业的储煤库存优化模型,以此确定最优库存决策,这将有利于燃煤发电企业将库存占用的资金降至合理水平,同时又能保证正常的发电运行。     

1 000 MW二次再热超超临界机组分散控制系统关键技术研究及应用

在分析二次再热机组控制难点的基础上,介绍了1 000 MW二次再热超超临界机组国产自主化分散控制系统关键技术的研发,包括机组分散控制系统的设计及技术特点,机组协调控制技术,汽温控制技术,旁路控制技术及机组自启停（APS）控制技术。示范工程的应用表明,该分散控制系统性能稳定可靠,各项性能指标达到或优于设计值,机组实现了启停全程控制自动化。     

黑麋峰电厂对湖南电网安全稳定影响分析

分析了黑麋峰电厂投运后,湖南电网的外送潮流特点及稳定水平,在此基础上研究了其对电网安全稳定运行的有利方面及不利一面,针对其对电网安全稳定运行可能会带来的问题,制定了相关应对措施,为运行好黑麋峰电厂,确保电网的安全稳定运行打下基础。     

相变换热器应用于电站锅炉的探讨

阐述了复合相变换热器是一种新型的换热器,可以控制低温受热面金属不发生低温腐蚀,降低烟气的排放温度,该技术可用于各种燃煤、燃油、燃气锅炉、窑炉、注气炉、加热炉等换热设备,目前复合相变换热器应用于工业锅炉和循环流化床已有不少成功案例[1-3],而应用于大型电站锅炉还很少有报道,结合某330 MW电站锅炉尾部加装复合相变换热器的运行情况,对复合相变换热器应用于电站锅炉的运行情况及优缺点做了简要探讨。     

300MW锅炉临炉加热系统改造分析

针对大唐河北发电有限公司马头热电分公司2台300MW锅炉启动时间较长的问题,从锅炉运行、设计两方面分析原因,提出改造锅炉底部加热系统的方案,并说明改造效果及改造效益.