传感器网络启动式自组织方法

无线传感器网络如何形成一个有序的自组织网络结构是一项重要研究内容,针对按地理区域交替性工作的动态监测网络,提出了相应的网络自组织方法,该方法以启动式方式运行网络,通过单播信令的方式分配MAC地址,标记相邻节点。在数据转发过程中以局部最小代价函数为准则转发数据。仿真实验表明,该自组织方法具有较短的MAC地址,适宜相应的网络环境。     

Synergistic effects of organically modified montmorillonite in combination with metal oxides on the fire safety enhancement of intumescent flame-retarded epoxy resins

Synergistic effects of organically modified montmorillonite (OMMT) in combination with different metal oxides (Bi₂O₃, Sb₂O₃, and MoO₃) on the fire safety enhancement of the intumescent flame-retarded epoxy resins (EPs) were systematically evaluated. The results from X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses show that the OMMT and metal oxides acquire a uniform distribution in the EP matrix, and OMMT platelets exhibit a fully exfoliated state. The flammability and thermogravimetry (TG) tests show that the intumescent flame retardant (IFR)-OMMT-metal oxide ternary system can endow EPs with the higher synergistic efficiencies on the enhancement of flame retardancy, smoke suppression properties, and charring ability compared to those of IFR or IFR-OMMT system, and the synergistic efficiency is the following order: IFR/OMMT/Sb₂O₃ > IFR/OMMT/MoO₃ > IFR/OMMT/Bi₂O₃. In particular, the sample, filled with 1.5 wt% OMMT, 1.5 wt% Sb₂O₃, and 27 wt% IFR, passes the UL94 V-0 rating and acquires the highest limiting oxygen index value of 28.5% among the samples. The IFR-OMMT-metal oxide ternary system exerts a better synergistic effect on the generation of crosslinking and aromatic structures that supply the excellent charring effect and barrier effect for the EPs, and the synergistic efficiency of IFR-OMMT-metal oxide ternary system is varied with the types of metal oxides.     

PSO-IIIA(3)亚砜萃取Pt(IV)的机理

研究表明,在酸性介质中,亚砜萃取Pt(Ⅳ)的主要机理为酸性缔合,其萃合物组成为H_2PtCl_6·6H_2O·2PSO。并计算了亚砜萃取Pt(Ⅳ)的萃取平衡常数。     

THE MIGRATION OF IMPURITY ATOMS AND HYDROGEN EMBRITTLEMENT CRACKING

<正> 一般认为裂纹材料的氢脆开裂是一个和氢原子扩散有关的过程。在负载条件下,氢原子将从四周扩散到裂纹尖端高应力区,当局部浓度达到临界值即起始开裂。开裂的每一步只能跃进一定距离,当裂纹扩展到氢含量很低的区域便暂时停止,然后,氢原子又再扩散聚集,如此往复,裂纹以不连续开裂方式向前扩展。     

TA15合金的热变形行为及加工图

研究了TA15合金的热模拟压缩实验。结果表明：变形温度的升高和应变速率的减小使峰值应力和稳态应力显著降低，变形温度会影响进入稳态流动所需变形量。以热模拟压缩实验为基础，建立的加工图表明：TA15合金高温变形时存在2个非稳定区域，一个是变形温度1300K以上和应变速率10．0s^-1以上的区域，另一个是变形温度1200K以下和应变速率0．006s^-1～1．995s^-1之间的区域。同时，建立的TA15合金高温变形时的流动应力模型表征了变形温度、应变速率和变形程度对流动应力的影响，模型的计算精度较高。     

基于压缩感知理论和二阶微分法的贯通式同相AT牵引供电系统牵引网输电线路单端保护方法

贯通式同相牵引供电系统能彻底解决电分相及负序问题,是目前高速铁路研究的重要方向.压缩感知技术在突破奈奎斯特采样定理对采样个数要求的同时能增强信号时聚性,并对故障暂态信号进行降噪.二阶微分法可以放大故障特征,解决高阻接地故障时故障分量过小而导致保护拒动的问题.提出用压缩感知技术对故障电流的线模信号进行压缩重构,再由二阶微分法处理压缩感知重构出的故障电流线模信号得到其首波头的幅值,将该幅值与预设阈值比较进而判断出故障位置的保护方法.利用PSCAD/EMTDC平台搭建贯通式同相AT牵引供电系统模型,通过改变故障位置、故障初始角及过渡电阻进行仿真实验,实验结果验证了该保护方法的有效性.     

高海拔变电站蓄电池及UPS容量选择及修正

高海拔地区环境温度、空气密度及气压低,在选择变电站站用蓄电池及UPS容量时应进行必要的修正,以满足变电站的用电需求。结合阿里与藏中联网工程的某500 k V变电站项目,对高海拔变电站蓄电池及UPS容量选择进行了探讨分析,希望能为类似工程提供参考。     

汽车涂装集中输调漆系统的发展现状

概述了汽车涂装集中输调漆系统的发展现状,描述了集中输调漆系统的一般构成,重点介绍了电动泵智能油漆循环系统和走珠式快速换色系统.     

Simulated Microgravity Inhibits the Proliferation of Chang Liver Cells by Attenuation of the Major Cell Cycle Regulators and Cytoskeletal Proteins

Simulated microgravity (SMG) induced the changes in cell proliferation and cytoskeleton organization, which plays an important factor in various cellular processes. The inhibition in cell cycle progression has been considered to be one of the main causes of proliferation inhibition in cells under SMG, but their mechanisms are still not fully understood. This study aimed to evaluate the effects of SMG on the proliferative ability and cytoskeleton changes of Chang Liver Cells (CCL-13). CCL-13 cells were induced SMG by 3D clinostat for 72 h, while the control group were treated in normal gravity at the same time. The results showed that SMG reduced CCL-13 cell proliferation by an increase in the number of CCL-13 cells in G0/G1 phase. This cell cycle phase arrest of CCL-13 cells was due to a downregulation of cell cycle-related proteins, such as cyclin A1 and A2, cyclin D1, and cyclin-dependent kinase 6 (Cdk6). SMG-exposed CCL-13 cells also exhibited a downregulation of α-tubulin 3 and β-actin which induced the cytoskeleton reorganization. These results suggested that the inhibited proliferation of SMG-exposed CCL-13 cells could be associate with the attenuation of major cell cycle regulators and main cytoskeletal proteins.