用单板机实现批量切削加工中的刀具补偿和质量管理

针对批量切削加工中的刀具磨损和质量管理问题，本文给出了用单板机进行刀具补偿控制的硬件、软件设计；并提出了用^-X图、R图进行质量管理的单板机实现。     

等离子光量计测定稀土矿中的稀土元素

本法采用P507淋洗萃取树脂富集稀土离子,在低酸度下解脱稀土元素。控制酸度在0.6MHCI下定容,采用自制新型可拆卸的循环雾化系统,以等离子光量计分别测定15个稀土分量,实验结果表明,稀土总量在毫克量级的各稀土回收率在96.48～97.5％之间,满足矿石中测定稀土元素的要求,相对标准偏差为±0.6～6.5％。     

废中温变换催化剂的综合利用

文章着重阐述了从废中温变换催化剂中，提取三氧化二铁和三氧化二铬的原理及其工艺，并论述了利用提取物制备铬盐和氧化铁红的方法。     

漂木道加糙齿水工模型试验

<正>漂木道是木材水运单漂水力过坝的一种构筑物。在上文中,我们曾对漂木道设计中的坡度、出口条件以及弯道超高等因子进行研究并取得了一定的成果。但由于上述研究中漂木道的底部设有三人字形加糙齿,水工模型试验和生产现场的原型观测都发现三人字形的加糙齿引起三股明显的翻花水,使水流渗气严重,大量单漂原木撞击漂木道槽底。因此,需要对加糙齿的形状作进一步的研究。     

分度装置中拨叉拨动点的位置对分度精度的影响

本文叙述了为磨制圆磨法齿轮滚刀的工作刀体和工艺刀体上的16等分刀片槽，而自行设计制造了由分度头、分度盘、尾座、拨叉和鸡心夹头组成的精密分度装置。由此提出了一个值得讨论的问题，即分度装置中拨叉拨动点位置影响着分度精度。本文给出了该装置分度误差及其变化规律的实测结果，又分析了产生分度误差的原因，最后得出了正确设置拨动点位置和提高分度的三点结论，对分度加工很有实际意义。     

结构阻尼系统的一种子结构综合方法

本文对结构阻尼系统提出一种模态综合方法,该方法特别适合于部件对接界面自由度较少情况下的结构综合.给出了一个算例来说明方法的有效性.     

Unbound or distant planetary mass population detected by gravitational microlensing

Since 1995, more than 500 exoplanets have been detected using different techniques, of which 12 were detected with gravitational microlensing. Most of these are gravitationally bound to their host stars. There is some evidence of free-floating planetary-mass objects in young star-forming regions, but these objects are limited to massive objects of 3 to 15 Jupiter masses with large uncertainties in photometric mass estimates and their abundance. Here, we report the discovery of a population of unbound or distant Jupiter-mass objects, which are almost twice (1.8(+1.7)(-0.8)) as common as main-sequence stars, based on two years of gravitational microlensing survey observations towards the Galactic Bulge. These planetary-mass objects have no host stars that can be detected within about ten astronomical units by gravitational microlensing. However, a comparison with constraints from direct imaging suggests that most of these planetary-mass objects are not bound to any host star. An abrupt change in the mass function at about one Jupiter mass favours the idea that their formation process is different from that of stars and brown dwarfs. They may have formed in proto-planetary disks and subsequently scattered into unbound or very distant orbits.     

实验教学改革的若干问题

从观念转变、体制改革、教学模式和方法的创新、师资队伍建设四个方面论述了实验教学改革存在的问题，强调了实验教学改革的必要性和重要性， 并提出了解决现行问题的方法和途径