圆柱直齿轮挤压组合凹模的优化设计

文章介绍了利用黄金迭代法对齿形凹模进行优化设计的过程.挤压齿轮的凹模型腔带有齿形,不能直接用厚壁圆筒的计算公式进行优化设计,但是可以利用组合凹模的优化设计公式,先确定凹模内圈、中圈、外圈的内外径尺寸,再与有限元模拟和迭代寻优相结合,以内圈的应力达到材料的许用应力值为目标,调整并优化过盈量,达到优化设计的目的.     

桥头跳车的原因和处理措施

在深入分析桥头不均匀沉降产生原因的基础上,从地基、路堤、路面等方面提出了桥头跳车的综合防治技术.     

车险中遏制投保人道德风险的博弈策略分析

针对车险中投保人既存在影响出险损失概率又存在影响出险损失规模的道德风险进行了研究,通过建立信号传递博弈模型,对投保人和保险人的博弈策略进行了分析并得出了解决投保人道德风险的应对之策。     

公示语的特征及其汉译英中的误译分析

随着国际交流的日益频繁,公示语已成为城市的窗口和名片,其规范翻译也更加重要。本文阐述了公示语的定义,从示意功能和文本类型两方面探讨了公示语的特征,在分析英语公示语语言特征的基础上对公示语汉译英中的误译进行分析,以期减少误译、规范译文,从而净化城市语言环境,进一步提升城市的文明程度和国际形象。     

空分常见“氮塞”故障分析及排除

空分产品氧取出量过大、上塔主冷中液氧液位过高或下塔液空纯度过低等异常都会引发"氮塞"故障,给氩系统的精馏工况,甚至企业的经济效益带来很大影响.对空分行业多种常见"氮塞"故障进行了分析,并提出了相应的排除方法.     

如何激发学生的创新意识

培养学生的创新意识、创新精神,训练学生的创新思维,开发学生的创新能力是每位教师义不容辞的责任.如何培养并激发学生的创新能力和创新意识呢?本文就此谈几点看法.     

居室的吊顶

根据居室的空间尺度及建筑结构，对居室吊顶的造型及色彩与灯光在造型中的运用进行了探讨．     

4-(2-吡啶偶氮)-邻苯二酚与Co(Ⅱ)、Co(Ⅲ)显色反应的分光光度研究

合成了新显色剂4-(2-吡啶偶氮)-邻苯二酚(PAPC)，并研究该试剂与Co(Ⅱ)、Co(Ⅲ)的显色反应。在pH=10.5缓冲溶液中，该试剂分别与Co(Ⅱ)、Co(Ⅲ)反应都能生成稳定的红色配合物，其最大吸收波长分别为518 nm和514 nm ,表观摩尔吸光系数分别为5.04×10     

用电子能量消失谱法研究P.tinctorius—P.massoniana菌根

在实验室条件下用12株外生菌根菌，对马尾松（Pinus massoniana)培养苗进行高效菌种的接种试验，筛选并证明分布于台湾的采色豆马勃（Pisolithus tinctorius)，具有生长快，对生态环境要求不严格，接种成功率大的特点。用能量消失谱技术对细胞内N、P营养元素进行定位测定，表明了这一菌株具有对N、P元素的吸收和贮存能力。     

Bathynotus: A key trilobite taxon for global stratigraphic boundary correlation between Cambrian Series 2 and Cambrian Series 3

The Cambrian trilobite Bathynotus is a special morphology of Redlichiid,which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long,backwardly directed spine.Additionally,its 12th and 13th pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural spine.The genus is widely distributed,occurring in North America,Siberia,the Altay-Sayan fold belt of Russia,South China,the Tarim Basin of China,and Australia.It occurs primarily in deposits of the upper part of the continental slope,at the transition between stable platform settings and subsiding margins of the late Early Cambrian.Here,we recognize three species of Bathynotus from China,including B.holopygus which is widespread around the world.Although six species of Bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia,data presented here suggest that only three of these species are valid.Bathynotus exhibits a short geological range,with its first occurrence late in the unnamed Cambrian Series 2 and the last appearance datum of Bathynotus at the boundary of Cambrian Series 2 and Cambrian Series 3.The late appearance datum (LAD) of Bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2 and Cambrian Series 3.