聚甲醛

The nucleation effect of nucleating agent HC (mainly containing salt of high molecular carboxylic acid) on polyoxymethylene was studied, and the effects of the nucleating agent on the crystalline morphology, crystallizability and crystallization rate of POM were also studied by means of DSC, PLM and isothermal crystallization kinetics analysis.

研究了高摩尔质量羧酸盐类成核剂HC对聚甲醛的结晶成核作用，采用示差扫描量热分析、偏光显微镜观察及等温结晶动力学分析等方法研究了该类成核剂对POM结晶形态、结晶度、结晶速率等的影响，并考察了其力学性能。

Objective: To compare the clinical effect of dental pulp devitalization with polyoxymethyleni and modified method respectively in two groups of patients with different age.

目的：比较改进多聚甲醛牙髓失活法与传统失活法的临床效果，并观察其在60岁以上老年人的效果差异。

Acid catalyst and H + catalysis in the acid catalysts were studied for synthesis of methyl glycolate via coupling of methyl formate and trioxane in a microform high-pressure autoclave(120mL).

在微型高压反应釜中(12 0ml)，考察了酸催化三聚甲醛和甲酸甲酯制备羟基乙酸甲酯的偶联反应，并对酸催化剂中H+的作用进行了研究。

The sythesis of methyl glycolate by methyl formate coupled with triformaldehyde with the catalyst of superphosphoric acid is exploring researched in this thesis. The point of exertion is the capacity of the new catalysts.

本研究主要对以过磷酸为催化剂催化甲酸甲酯与三聚甲醛偶联合成乙醇酸甲酯进行考查，通过对以过磷酸、浓硫酸及过磷酸与浓硫酸混合酸催化剂时反应现象、乙醇酸甲酯产率等的对比，研究以过磷酸为催化剂偶联合成乙醇酸甲酯反应的催化活性。

If cells are not fixed with paraformaldehyde, keep the samples on ice and run them immediately after staining is accomplished

如果做好不能及时检测，我们一般是加入等量的2%的多聚甲醛固定，4度冰箱避光贮存。

If cell s are not fixed with paraformaldehyde, keep the samples on ice and run them immediately after staining is accomplished

如果做好不能及时检测，我们一般是加入等量的2%的多聚甲醛固定，4度冰箱避光贮存。

The experimental group was given an operation of cutting infundibulum and the contol group was given an exposure of not cutting the infundibulum.Both groups were raised under similar condition.After surviving for 30 days,the animals were killed and specimens from aorta were taken and observed under light and electron microscope.

实验组行手术切断漏斗，对照组行手术暴露但不切断漏斗，手术后2d，两组动物移至同一条件下饲养，存活30d后用1%多聚甲醛+1.25%戊二醛液从心脏灌流固定，取主动脉作光、电镜观察。

Under water lubrication condition, its coefficient of kinetic friction compared to pa66 and metaformaldehyde low half.

在水润滑条件下，其动摩擦系数比pa66和聚甲醛低一半。

But harm of lead is revealed in the course of application. It is an urgent problem to develop new leadless POM composites.

含铅聚甲醛复合材料，由于具有良好的自润滑性能，其应用范围不断扩大，然而在使用过程中，铅的危害不断暴露出来，迫使人们加快对无铅POM复合材料的研究步伐。

In this paper the nucleation of nucleator C to polyacetal was investigated by means of DSC, PLM, WAXD and testing of mechanical properties.

本文利用差热分析仪、偏光显微成核剂的作用镜、广角X射线衍射仪及力学性能测试设备考察了成核剂C对聚甲醛的成核作用。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。