催化电位法测定人发中痕量碘

采用碱灰化法消解发样,于中性溶液中离心去除杂质,在酸性溶液中以催化电位法测定发碘含量,回收率达98.6％;变异系数(CV)为8.7％;测出中碘地区一个教学班20名男学生发碘平均含量为0.93μg/g,与文献报道相近。     

THE PRACTICE OF ACRYLIC SIROSPUN YARN ON THE SEMI WORSTED SPINNING FRAME

The technique of sirospun process is applied on a modified semi-worsted balloonless spinningframe to investigate the effect of spindle-speed,yarn-twist and strand-spacing on yarn properties.Yarn breaking strength,breaking extension,evenness and imperfection are examined on the basisof CCD experimental design.Yarn hairiness is particularly concerned,being found that all spinningparameters tested have significant effects on hairiness and that the minimum number of hairs oc-curs at the strand-spacing of 14.4 mm.Compared to conventional single spun yarn,experimentshave revealed the greatest advantage of using sirospun process is that all sirospun yarns have muchless hairiness.A new sirospun yarn fault,so called“loop”,has also been examined.The most likely cause forthis yarn fault is the strand-tension unbalance between the two strands when low tension spinningis applied.Further analysis and some initial tests have been carried out in the hope of overcomingthis loop fault which is an important obstacle to the application of balloonless spinning.     

柔性变截面滑移式机械手的控制

研究了柔性变截面滑移式机械手臂的控制。首先，基于有限元法导出系统的动力学方程，然后分别建立了两种控制方式的状态方程：１）以加速度和角加速度作为控制变量：２）以力和力矩作为控制变量。控制过程分为“粗控”和“精控”两步进行。“精控”过程采用线性二次型高斯控制。最后给出了数值模拟的结果。     

模型优适度辨识含水层补给进口的原理、方法和应用

本文阐述了一种新的研究成果——用模型优适度寻找含水层主进水口位置的原理、方法和应用。模型优适度作为衡量地下水模型场势与原型(矿区)场势相似拟合程度的量度,它凭借含水层地下水场势对源点的响应差异,判别模型源点位置与原型源点位置是否一致、接近或偏离。本文给出了模型优适度的计算公式和用统计分析方法对动态矩阵施行标准化的公式推演过程。通过多次模拟试验,绘出优适度的等值线图,为华北某矿圈定含水层补给范围,进行注浆堵水,大大地降低了矿井涌水量,在实践应用中获得初步成功。     

丙酮缩二甲醇的合成及应用

介绍了丙酮缩二甲醇的合成方法及其主要用途,概要地报道了合成丙酮缩乙二醇及以此为原料合成丙酮缩二甲醇的新工艺。     

三球式和转台式角动量守恒演示器的研制与应用

本文详细介绍了笔者研制的三球式和转台式两种新型角动量守恒演示器的结构、特点和使用方法。     

球电流壳磁场的计算

计算的结果表明，球壳内的磁场是均匀的，可用此方法在一定范围内获得均匀磁场．     

“926”植物生长调节剂的药效作用及机理研究

试验表明，“９２６”植物生长调节剂对植物种子活力、根系活力、植物生长发育具有明显的促进作用。用“９２６”浸稻种和玉米种，可提高发芽势、发芽率，增加次生根数和次生根长。苗期施药，同样可促进幼苗生长发育、促进根系发育、增加分蘖、分枝，提高成穗率。其它生育期施药，可分别提高成稳率、穗粒数、粒重，显著提高作物产量。     

Local one-dimensional ase-i scheme for 2D diffusion equation

A local alternating segment explicit—implicit method for the solution of 2D diffusion equations is presented in this paper. The method is unconditionally stable and has the obvious property of parallelism. Some numerical experiments show the method is not only simple but also more accurate.