感耦等离子体原子发射光谱法测定高纯铅中杂质元素的干扰研究

文章介绍了用ＩＣＰ－ＡＥＳ法测定高纯铅中杂质元素时，Ｐｂ对分析元素的干扰情况。Ｐｂ对Ｇｅ、Ｍｏ、Ｐ、Ａｓ、Ｆｅ、Ｂｉ、Ｍｎ有背景影响，对Ｓｂ产生谱线干扰。１０ｍｇ／ｍｌ的Ｐｂ分别产生相当于０．２３５μｇ／ｍｌＡｓ、０．７５０μｇ／ｍｌＰ、０．３３５μｇ／ｍｌＭｏ和３．９５０μｇ／ｍｌＳｂ的信号。     

虚拟仪器技术在雷达系统测试中的应用

分析了现代雷达系统对新一代雷达测试系统的要求,总结了虚拟仪器的发展、优势和关键技术,并对新一代雷达测试系统进行了展望.     

高炉铁口孔道侵蚀过程的模拟

从流体动力学的角度出发,建立高炉出铁口处流动的数学模型.基于对孔口出流出口处流线公式的推导并作适当修正,计算出铁时铁口孔道的侵蚀形状,并描述了侵蚀过程.通过水模型实验和模拟计算的方法分别模拟出侵蚀过程.实验与模型假设较为符合,可以为铁口区的维护以及推荐适宜的打泥量提供参考.     

FvNST1b NAC Protein Induces Secondary Cell Wall Formation in Strawberry

Secondary cell wall thickening plays a crucial role in plant growth and development. Diploid woodland strawberry (Fragaria vesca) is an excellent model for studying fruit development, but its molecular control of secondary wall thickening is largely unknown. Previous studies have shown that Arabidopsis NAC secondary wall thickening promoting factor1 (AtNST1) and related proteins are master regulators of xylem fiber cell differentiation in multiple plant species. In this study, a NST1-like gene, FvNST1b, was isolated and characterized from strawberry. Sequence alignment and phylogenetic analysis showed that the FvNST1b protein contains a highly conserved NAC domain, and it belongs to the same family as AtNST1. Overexpression of FvNST1b in wild-type Arabidopsis caused extreme dwarfism, induced ectopic thickening of secondary walls in various tissues, and upregulated the expression of genes related to secondary cell wall synthesis. In addition, transient overexpression of FvNST1b in wild-type Fragaria vesca fruit produced cells resembling tracheary elements. These results suggest that FvNST1b positively regulates secondary cell wall formation as orthologous genes from other species.     

某四层砖混结构千斤顶顶升纠倾方案研究与应用

根据某四层砖混结构半幢楼下沉、倾斜、扭转以及墙体严重开裂等现象,应用工程概念(如结构变形协调原理等),采用单排千斤顶并用人工操作方式将半幢楼成功顶升纠倾,证明该技术能够应用于无圈梁无构造柱整体性较差的砖混结构。     

一维纳米氧化锌制备方法及生长机理浅析

氧化锌(ZnO)是一种优良半导体材料,一维纳米结构ZnO因其极大地应用前景,更是引起了研究者的高度关注与深入研究。归纳、分析一维纳米ZnO的气相、液相、固相三类制备方法及其生长机理,深刻剖析气相制备方法的三种生长机制及其研究概况,为实现一维纳米ZnO的可控制备提供研究基础,对一维纳米ZnO制备方法的研究具有一定的理论指导意义。     

Unkeito Suppresses RANKL-Mediated Osteoclastogenesis via the Blimp1–Bcl6 and NF-κB Signaling Pathways and Enhancing Osteoclast Apoptosis

Osteoporosis is a common bone disease, particularly in menopausal women. Herein, we screened four Kampo medicines (Unkeito (UKT), Kamishoyosan (KSS), Kamikihito (KKT), and Ninjinyoeito (NYT)), frequently used to treat menopausal syndromes, for their effects on receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclast differentiation in RAW 264 cells. Considering that UKT exhibited the most potent effect, we examined its effect on RANKL-induced osteoclastogenesis, the induction of osteoclast apoptosis, and the mechanisms underlying its effects. UKT inhibits RANKL-induced osteoclast differentiation in the early stage and decreases osteoclast-related genes, including tartrate-resistant acid phosphatase (Trap), dendritic cell-specific transmembrane protein (Dcstamp), matrix metalloproteinase-9 (Mmp9), and cathepsin K (Ctsk). Specifically, UKT inhibits the nuclear factor of activated T cells 1 (NFATc1), which is essential for osteoclastogenesis. UKT increases Bcl6, which antagonizes NFATc1 and Dc-stamp, thereby blocking the progression of osteoclasts to maturation. UKT also decreased nuclear translocation by downregulating the activity of p65/NF-κB. In addition, UKT enhances mononuclear osteoclast apoptosis via activation of caspase-3. Herein, we demonstrate that UKT suppresses RANKL-mediated osteoclastogenesis via the Blimp1–Bcl6 and NF-κB signaling pathways and enhances mononuclear osteoclast apoptosis. Furthermore, UKT prevents bone loss in OVX mice. Thus, UKT might be a potential therapeutic agent for postmenopausal osteoporosis.     

高邮湖退圩还湖关键问题的探讨与分析

高邮湖承接了淮河入江水道改道段下泄的淮河洪水,是淮河入江的重要行水通道.对高邮湖的治理已经从工程的角度投入了大量的工作,比如高邮湖控制工程、新民滩工程、入江水道整治等等.但由于历史上的围垦以及近年来的圈圩养殖与围网养殖,大大减小了湖泊的自由水面,减小了湖泊的防洪库容,影响了高邮湖的防洪功能.控制工程的建设与投入固然重要...     

钢的裂纹研究思路及应注意的问题

研究钢的裂纹,要确定裂纹的特征和产生裂纹的影响因素。经过分析,初步确定出裂纹产生的原因,然后采取改进措施,反复实践,直到最终消除裂纹。提出研究钢的裂纹,要注意结合各种专业知识,善于积累现场经验和借鉴他人的工作成果;掌握数理统计及物理检验的方法,提高调查研究的能力等方面的建议。     

基于概率神经网络-小波神经网络-DS信息融合的电厂引风机故障诊断

针对电厂引风机工况复杂、工作环境恶劣、易出现故障等问题,提出了一种基于改进D-S证据理论的融合诊断方法。该方法利用概率神经网络(probabilistic neural network, PNN)和小波神经网络(wavelet neural network,WNN)对测试样本进行初步诊断,并形成证据体,再利用改进D-S融合方法进行融合诊断。该融合方法根据证据体的信任度和焦元的信任度分配冲突信息,使得信任度高的焦元支持率得到加强、信任度低的焦元支持率得到削弱,融合结果更为合理。仿真结果表明,融合故障诊断方法能有效地避免误诊现象,提高了诊断的正确率,且能合理分配冲突信息。