挤压渗流铸造泡沫铝合金的工艺因素探讨

本文采用正交试验的方法对泡沫铝合金的制做原理及渗流铸造工艺进行了探讨。认为多孔体的制椒是获得良好的泡状组织的基础；模具与多孔体的预热温度和浇属液的浇注温度是保证海绵铝质量的关键。     

相似模拟实验中近景摄影测量的应用

给出了应用近景摄影测量测点位移的计算数学模型，并结合实验要求分析了测量精度，使相似模拟实验可借助计算机用解析法近景摄影来完成测点位移测量。此方法不仅提高了实验水平，而且简化了实验工作。     

单子叶植物核DNA含量地理纬度变异式样及其与气候因素关系

从"植物DNA C-值数据库"检索到2 852种单子叶植物的核DNA含量数据,沿经度方向均分为10条样带,每条样带沿纬度又均分成19个样块.从"世界气候数据网站"下载的19个生物气候因子数据,应用Arc GIS 9.3获得每个样块生物气候因子的平均值.根据"全球生物多样性信息网站"记录,计算每个样块的单子叶植物的平均核DNA含量.分析了最冷季度平均温度和最干季度雨量对单子叶植物核DNA含量的影响.应用分位数回归分析了核DNA含量不同的单子叶植物在全球范围的纬度梯度变化特点,以及气候适应性的差异.结果发现:单子叶植物的核DNA含量沿着纬度呈现非线性的规律变化;受气候因素影响,在中等温度和雨量环境下其核DNA含量最高,温度和水分趋向极端的环境下其核DNA含量较低,可以用"单峰"函数拟合;核DNA含量低的类群具有更广泛的全球分布.     

浅谈公路路基地质病害类型及处治对策

与工程实际相结合,阐述经常遇见的不良路基地质病害以及各种病害的特点,并简述对这些不良的工程地质病害进行正确的评价,同时对这些不良地质病害提出了相应的防治对策。     

The study on the block boundary’s driving forces and tectonic stress field of China mainland and its adjacent areas using GPS data

After reviewing the inversion study on the driving forces of China mainland and its adjacent areas, the inversion computation is made by means of genetic finite element method and covering complex method based on the displacement observations of the Crustal Movement Observation Network of China. The whole procedures of inversion study, including parameter selection, computation conditions, inversion analysis and interpretation, are given out in details. Then some conclusions are drawn:(1)the main driving forces acting on China mainland are still from the collision of Indian plate with Eurasian plate;(2)the driving forces of Pacific plate and Philippine plate are significant to the eastern China;(3)the back basin of Japan sea arc is continuously extending;(4)the forces from north prevent the northern motion of China.     

试论人力资源与人力资本

文章对人力资源和人力资本的基本区别与联系及有机的融合做了粗浅的论述和探讨。     

饲料钙含量的检测方法比较

文章对饲料钙合量的检测方法进行了认真的比较。     

中国干旱状况的时空分布特征及影响因素

基于高分辨率CRU数据集1950-2009年的逐月资料,计算湿润指数,采用回归分析和偏相关方法分析中国区域干湿变化特征及原因.结果表明,1950-2009年中国总体呈现明显的干旱化趋势,以秋季最为显著;中国降水量呈现微弱的增加趋势(0.04 mm/10 a),潜在蒸发量呈现显著增加趋势(0.71 mm/10 a),潜在蒸发量的显著增加促进了中国干旱化.湿润指数变化的空间分布在东部和西部地区呈相反的趋势,降水量减少而潜在蒸发量增加的共同作用成为东部地区干旱化的直接原因;降水量增加而潜在蒸发量减少(微弱增加)为西部地区干旱适度缓解的直接原因.太阳短波辐射对潜在蒸发量的影响最大,其次为平均温度、水汽压、温度日较差、云量和降水量.     

The structural basis for activation of plant immunity by bacterial effector protein AvrPto

Pathogenic microbes use effectors to enhance susceptibility in host plants. However, plants have evolved a sophisticated immune system to detect these effectors using cognate disease resistance proteins, a recognition that is highly specific, often elicits rapid and localized cell death, known as a hypersensitive response, and thus potentially limits pathogen growth. Despite numerous genetic and biochemical studies on the interactions between pathogen effector proteins and plant resistance proteins, the structural bases for such interactions remain elusive. The direct interaction between the tomato protein kinase Pto and the Pseudomonas syringae effector protein AvrPto is known to trigger disease resistance and programmed cell death through the nucleotide-binding site/leucine-rich repeat (NBS-LRR) class of disease resistance protein Prf. Here we present the crystal structure of an AvrPto-Pto complex. Contrary to the widely held hypothesis that AvrPto activates Pto kinase activity, our structural and biochemical analyses demonstrated that AvrPto is an inhibitor of Pto kinase in vitro. The AvrPto-Pto interaction is mediated by the phosphorylation-stabilized P+1 loop and a second loop in Pto, both of which negatively regulate the Prf-mediated defences in the absence of AvrPto in tomato plants. Together, our results show that AvrPto derepresses host defences by interacting with the two defence-inhibition loops of Pto.     

基于.NET组件技术的强磁选过程智能优化设定控制系统开发

为解决赤铁矿强磁选过程运行因工艺生产指标无法在线连续检测而难以实施闭环优化控制的问题,将过程知识、专家经验与过程数据相结合,设计了由基于案例推理的回路预设定模型、小波神经网络软测量模型以及专家规则补偿器构成的智能优化设定控制器.针对已有优化控制软件存在的标准化程度低、可扩展性差、资源无法复用等问题,设计并开发了基于.N...