Cytogenetic and Molecular Marker Analyses of a Novel Wheat–Psathyrostachys huashanica 7Ns Disomic Addition Line with Powdery Mildew Resistance

Powdery mildew caused by Blumeria graminis f. sp. tritici is a devastating disease that reduces wheat yield and quality worldwide. The exploration and utilization of new resistance genes from wild wheat relatives is the most effective strategy against this disease. Psathyrostachys huashanica Keng f. ex P. C. Kuo (2n = 2x = 14, NsNs) is an important tertiary gene donor with multiple valuable traits for wheat genetic improvement, especially disease resistance. In this study, we developed and identified a new wheat—P. huashanica disomic addition line, 18-1-5—derived from a cross between P. huashanica and common wheat lines Chinese Spring and CSph2b. Sequential genomic and multicolor fluorescence in situ hybridization analyses revealed that 18-1-5 harbored 21 pairs of wheat chromosomes plus a pair of alien Ns chromosomes. Non-denaturing fluorescence in situ hybridization and molecular marker analyses further demonstrated that the alien chromosomes were derived from chromosome 7Ns of P. huashanica. The assessment of powdery mildew response revealed that line 18-1-5 was highly resistant at the adult stage to powdery mildew pathogens prevalent in China. The evaluation of agronomic traits indicated that 18-1-5 had a significantly reduced plant height and an increased kernel length compared with its wheat parents. Using genotyping-by-sequencing technology, we developed 118 PCR-based markers specifically for chromosome 7Ns of P. huashanica and found that 26 of these markers could be used to distinguish the genomes of P. huashanica and other wheat-related species. Line 18-1-5 can therefore serve as a promising bridging parent for wheat disease resistance breeding. These markers should be conducive for the rapid, precise detection of P. huashanica chromosomes and chromosomal segments carrying Pm resistance gene(s) during marker-assisted breeding and for the investigation of genetic differences and phylogenetic relationships among diverse Ns genomes and other closely related ones.     

数据驱动的航天器故障诊断研究现状及挑战

总结了基于数据驱动的故障诊断技术理论、方法及其在航天器上的应用现状,指出其面临的挑战并提出一种解决方案。将基于数据驱动的故障诊断方法按照技术发展顺序分为基于传统机器学习的方法、基于深度学习的方法以及基于迁移学习的方法。基于传统机器学习的方法需要大量的人工参与和丰富的专家经验,在小样本数据上有着优异的性能,但不适合处理大数据。在大数据背景下,重点介绍了卷积神经网络、循环神经网络、深度自编码器以及深度信念网络的基本概念以及原理,对其在航天器故障诊断领域的研究现状进行了阐述和总结。针对深度学习严重依赖于带标签数据这一问题,介绍了基于迁移学习的故障诊断技术,并提出适应航天器应用的场景,为数据驱动的故障诊断技术工程应用提供了一种方法和思路。     

Highly Stretchable and Sensitive Flexible Strain Sensor Based on Fe NWs/Graphene/PEDOT:PSS with a Porous Structure

With the rapid development of wearable smart electronic products, high-performance wearable flexible strain sensors are urgently needed. In this paper, a flexible strain sensor device with Fe NWs/Graphene/PEDOT:PSS material added under a porous structure was designed and prepared. The effects of adding different sensing materials and a different number of dips with PEDOT:PSS on the device performance were investigated. The experiments show that the flexible strain sensor obtained by using Fe NWs, graphene, and PEDOT:PSS composite is dipped in polyurethane foam once and vacuum dried in turn with a local linearity of 98.8%, and the device was stable up to 3500 times at 80% strain. The high linearity and good stability are based on the three-dimensional network structure of polyurethane foam, combined with the excellent electrical conductivity of Fe NWs, the bridging and passivation effects of graphene, and the stabilization effect of PEDOT:PSS, which force the graphene-coated Fe NWs to adhere to the porous skeleton under the action of PEDOT:PSS to form a stable three-dimensional conductive network. Flexible strain sensor devices can be applied to smart robots and other fields and show broad application prospects in intelligent wearable devices.     

乌镇古镇滨水建筑外部空间研究

外部空间元素通过一定的组织手法有规律地形成了乌镇古镇的外部空间结构。使用建筑设计中的平面关系图和剖立面图来解析外部空间结构,从而清晰、明确体现这种外部空间结构,并总结出乌镇古镇外部空间的平面关系和剖立面关系的特点以及与西塘、南浔古镇的异同。     

磨机负荷检测系统无线数据采集装置的研制

针对球磨机振动信号采集及数据传输,研制了一套低功耗无线采集传输系统。通过对电路系统的降噪设计,提高了处理精度,使其完全满足数据采集的需要,解决了在线检测球磨机桶壁振动装置的连续使用问题。     

2205双相不锈钢摩擦焊接头显微组织及微区蠕变性能

对2205不锈钢进行连续驱动摩擦焊接,通过光学显微镜观察接头显微组织,利用纳米压痕仪对接头组织中铁素体(δ相)和奥氏体(γ相)进行硬度测试及压痕蠕变行为分析。结果表明,摩擦焊接头由塑性变形区及焊合区构成,变形区内γ相与δ相相比,因塑性流动而硬化的现象更为显著,且具有更高的纳米硬度和弹性模量;基于保载过程中应变率和硬度对数关系,经线性拟合得到蠕变应力指数n,能够较好地反映δ相和γ相的蠕变特性,而且纳米硬度值越高,蠕变应力指数越小。     

分布式组件架构的信息化系统开发平台设计与实现

随着互联网技术的快速发展,新技术的不断出现,信息平台也需要不断升级更新以适应更多元化的需求和更大量的数据。传统的信息化开发平台受限于当时技术的发展,采用前后端结合的开发模式,在一些功能上前后端互相限制,使得在大量数据交互时效率不高,而且平台在维护升级时工作量大等等。本文设计了采用前后端分离实现的方式设计实现的新型平台,前后端分离的方法可以使后端服务组件分布式布置,提供更高效、规范的服务,前端通过调用不同组件实现各种功能,以提供底层技术架构和通用模块,可以让开发人员把精力更多的集中于业业务。并在此基础上阐述了设计目标、架构设计及功能设计等几个方面。     

基于BIM理念的绿色建筑新思维

通过BIM精细化设计, 使用统一的数据源, 保持整个设计过程数据的可持续性, 对设计各阶段进行优化, 使设计作品达到绿色建筑设计的要求。此外, 使用数字模拟软件Ecotect、Fluent、Abaqus、Pathfinder等对光照、风环境、荷载、人员疏散进行模拟分析, 并通过模拟结果来优化建筑开窗、建筑遮阳、建筑抗震、建筑疏散以及可再生能源的利用, 提升设计质量, 保证设计的安全性、节能性、环保性和可持续性, 使图书馆具有更适合学习和生活的室内外环境, 达到“人-建筑-自然”三者和谐共生。     

食品和食品包装材料中全氟化合物(PFCs)的研究进展

全氟化合物(perfluorochemicals,PFCs)具有持久性、生物累积性,被列入新型持久性有机污染物,目前已成为环境与食品安全研究的热点领域。全氟化合物主要包括稳定态和离子态氟化物,被广泛应用于表面活性剂、食品包装、不粘锅涂层等与食品包装及加工相关的领域。本文对PFCs的理化性质、应用、毒性作用以及在食品中的污染水平进行了评述,重点探讨了其在食品中的分析测定方法,以期为我国开展食品领域内全氟化合物的风险评估及相关研究提供参考。