Strength,strain capacity and toughness of five dual-phase pipeline steels

The effect of microstructures on strength, strain capacity and low temperature toughness of a micro-alloyed pipeline steel was elucidated. Five various dual-pha...     

点云空间与反射强度融合的非结构化道路可行驶区域检测

可行驶区域检测旨在检测和提取智能车辆在道路上可行进的区域, 目前主流的检测方法主要基于三维激光雷达的空间特征实现, 难以处理路面边缘无清晰空间特征的非结构化道路. 为此, 本文提出了一种基于点云空间和反射强度融合的非结构化道路可行驶区域检测方法. 首先, 通过融合反射强度因子改进了基于空间特征的柱坐标系检测模型; 然后, 使用强度和降维空间检测对检测精度较低的环形检测模型进行优化, 并将其与柱坐标系检测模型联合使用以提高方法检测准确率; 最后, 在自录实际道路数据集上进行对比实验. 实验结果表明本文方法显著提高了非结构化道路可行驶区域检测的成功率与精确率, 在结构化道路上也具有良好效果.     

Acanthopanax senticosus Polysaccharide Enhances the Pathogen Resistance of Radiation-Damaged Caenorhabditis elegans through Intestinal p38 MAPK-SKN-1/ATF-7 Pathway and Stress Response

With the advancement of science and technology, humans are chronically exposed to ionizing radiation. It is crucial to look for efficient and low-toxic anti-radiation agents. Through preliminary screening, we found that Acanthopanax senticosus polysaccharide (ASPS) played a major role in regulating immune damage caused by radiation. The objective of this study was to apply the Caenorhabditis elegans—P. aeruginosa (PA14) infection model to illuminate the mechanism of ASPS increasing the pathogen resistance of radiation-damaged nematodes. Results indicated that ASPS (1 mg/mL) significantly enhanced the pathogen resistance of radiation-damaged nematodes by directly elevating the immune response of nematodes rather than by affecting the bacterial activity. Through further research on the p38 MAPK signaling pathway and related mutants, we found that ASPS functioned by the p38 MAPK pathway in the intestine, and SKN-1, ATF-7 as the downstream targets of PMK-1 participated the regulation of ASPS. In addition, ASPS markedly alleviated the stress status of damaged nematodes by regulating oxidative stress. Collectively, our findings suggest that ASPS enhances the pathogen resistance of radiation-damaged nematodes through the intestinal p38MAPK-SKN-1/ATF-7 pathway and stress response.     

基于熵相关系数的关联性自动判别方法——COCA

数据库自管理、自调优中查询计划的自动优化是目前的关注热点。为保证优化器估值精度,用统计学方法,给出了一种基于熵相关系数的对字段关联性的自动判别的新算法——COCA。该算法有下列特点：（1）限制少,没有卡方检验的频数限制,卡方检验只有在列联表中至少有80%的格子频数大于5的情况下才可信; （2）结果多,卡方检验（CORDS）只判断字段之间是否有关联,新方法可计算字段之间双向的关联程度。实验表明, 新方法更坚固,产生更多的统计信息,可以支持后面更高效、准确地建立直方图。     

Shaping the interdisciplinary knowledge network of China: a network analysis based on citation data from 1981 to 2010

This study builds the interdisciplinary knowledge network of China, which is used to catch the knowledge exchange structure of disciplines, and investigates the evolution process from 1981 to 2010. A network analysis was performed to examine the special structure and we compare state of the networks in different periods to determine how the network has got such properties. The dataset are get from the reference relationship in literature on important Chinese academic journals from 1980 to 2010. The analytical results reveal the hidden network structure of interdisciplinary knowledge flows in China and demonstrate that the network is highly connected and has a homogeneous link structure and heterogeneous weight distribution. Through comparing of the network in three periods, that is 1981–1990, 1991–2000 and 2001–2010, we find that the special evolution process, which is limited by the number of nodes, play an important influence on interdisciplinary knowledge flows.     

温敏型有机-无机杂化纳米微胶囊的渗透性能

将N-异丙基丙烯酰胺引入以正十六烷为模板的苯乙烯与甲基丙烯酸-3-三甲氧基硅丙酯细乳液共聚法制备纳米微胶囊的体系,得到一种温敏型有机-无机杂化纳米微胶囊。采用紫外可见分光光度计研究该种微胶囊在临界温度附近对甲酚红的载入和释放行为。结果表明N-异丙基丙烯酰胺的引入和温度均影响纳米微胶囊对甲酚红的载入与释放。微胶囊在临界温度以上具有一定渗透速率,临界温度以下渗透不明显,能较好地实现开-关式环境温敏型控制吸附和释放。     

SCR反应器导流板及喷氨面的优化设计

根据某发电机组的选择性催化还原(SCR)技术烟气脱硝系统的运行参数,对设置不同直型导流板和喷氨面的反应器流场进行模拟,得到SCR烟气脱硝系统的最佳布置方案.使用Gambit软件构造模型,利用Fluent软件进行数值计算得到流场烟气速度分布和NO质量分数分布.分析表明,设置直型导流板可使催化剂层的烟气流场速度分布更均匀;直型导流板数量一定时,增大其倾斜角度有利于改善烟气流场速度分布;角度不变增加直型导流板数量不利于烟气流场速度分布;设置6块倾斜角度为80°的直行导流板,喷氨面位于烟道中部为最佳布置.     

袖珍型数字式光纤耦合比色仪

为满足现代生产生活中对颜色快速测量的需求,设计了一种基于RGB三基色原理,采用光纤波导及融合技术、应用白平衡调节手段的数字式比色仪。仪器由白光LED光源、Y型混合石英光纤束光波导探头、微透镜发射耦合及透镜准直接收部件、以颜色传感器和MSP430单片机为核心的信号采集及处理部件等组成,采用C语言编程进行数据采集、存储、白平衡调整、颜色识别及显示。经与比色卡对比测试,其测量准确度和速度相对于当前广泛应用的比色卡均有很大提高。     

超高压直流系统中的直流滤波器保护

介绍了超高压直流输电系统中的直流滤波器保护,分析了直流滤波器的特点以及超高压直流输电的各种运行工况对直流滤波器保护带来的影响,提出了直流滤波器保护的总体设计思想、相应的保护原理与方案,重点讨论了差动保护和不平衡保护的实现及其应该注意的问题。     

FT-NIR快速同时测定香精香料理化指标

建立了一种快速同时测定香精香料理化指标的方法.利用傅里叶变换近红外光谱（FTNIR）技术,建立了香精香料的折光指数、pH、相对密度及挥发总量四种理化指标的预测模型,同时考察了光谱预处理方法对模型的影响,并对模型预测结果的准确性与重复性进行了评价.结果表明,所建模型适用于不同种类的香精与料液,可快速同时对样品的折光指数、pH、相对密度及挥发总量四种理化指标进行预测,预测均方差RMSEP分别为0.00182,0.374,0.00393与3.04.可见,近红外光谱技术能够对烟用香精香料进行快速、无损与同时分析,并满足实际测量要求.