聚甲醛

In this paper, methylal and diethoxymethane were used as end capping agents to improve the thermal stability of the product in molten copolymerization of trioxane with ethylene oxide or with dioxolane.

为此研究了在三聚甲醛与环氧乙烷或三聚甲醛与二氧五环熔融共聚体系中，通过封端剂甲缩醛或二乙氧基甲烷的使用，对热碱稳定的共聚甲醛的收率提高了3％左右。

Since it is easy to store, transport and use, Paraformaldehyde is traded in different package.

由于多聚甲醛具有贮存、运输和使用方便等优点，国际上通常用不同规格的多聚甲醛这种产品形式进行一定量的甲醛贸易。

In the rotation diagram of polytrioxane obtained by γ-irradiation of trioxane there appear some new diffraction spots in addition to that for ordinary polyoxymethylene.

在辐照聚合制得的聚三聚甲醛的迴转图上，除出现普通聚甲醛的衍射点外，还存在着一些新的衍射斑点。

The kinetics and mechanism of thermooxidative degradation of polyoxymethylene, and the effects of temperatures on the initial degradation rate and life time of POM, were studied in air by isothermal TG and FTIR analysis of the residue.

通过等温热失重和残留物红外光谱研究了聚甲醛在空气条件下的热氧降解动力学及机理，讨论了温度对聚甲醛初始降解速率以及热老化寿命的影响。

High molecular weight polyoxymethylene was obtained from trioxane crystal by solid state polymerization with γ-irradiation from Co80 source.

用Co~(60)γ射线辐照三聚甲醛晶体固相聚合得到高分子量的聚甲醛。

Polyoxymethylene with wry high degree of erystallinity cain be obtained by γ-irradiation of trioxane single crystals with Co60 source.

三聚甲醛单晶经Co60γ射线辐照可以得到一种结晶度很高的聚三聚甲醛。

Binary blends of polyoxymethylene/co-polyamide and ternary blends of poly- oxymethylene/co-polyamide/ethylene-vinyl (POM/COPA/EVA) were prepared and the effect of COPA and EVA contents on properties of blends was investigated.

研究了聚甲醛/共聚酰胺二元及聚甲醛/共聚酰胺/乙烯-醋酸乙烯酯共聚物(POM/COPA/EVA)三元共混物，探讨了COPA、EVA用量对共混体系性能的影响。

Through practice we know that when the thickness of polyformaldehyde layer is proper (excluding the thickness of polyformaldehyde between the large-grained copper powder and screw copper nails), it has a good comprehensive ability of load-bearing, friction and wear endurance and creep resistance.

我们通过实践了解到，聚甲醛层在适宜的厚度适宜（不含嵌入到大颗粒铜粉及螺旋铜钉间隙内聚甲醛厚度）时，其承载能力、摩擦磨损性能和抗蠕变能力的综合特性较好。

Through practice we know that when the thickness of polyformaldehyde layer is proper (excluding the thickness of polyformaldehyde between the large-grained copper powder and screw copper nails), it has a good comprehensive ability of load-bearing, friction and wear endurance and creep resistance.

我们通过实践了解到，聚甲醛层在适宜的厚度时（不含嵌入到大颗粒铜粉及螺旋铜钉间隙聚甲醛厚度，其承载能力、摩擦磨损性能和抗蠕变能力的综合特性较好。

The large-grained spherical copper powder is well compatible and binds securely with the small-grained spherical copper powder. Moreover, the large-grained copper powder has greater gaps between the grains.

小颗粒球形铜粉与钢基体接触面积大，烧结过程中结合牢固、充分，大颗粒球形铜粉与小颗粒球形铜粉烧结相容性好，结合牢靠，并且大颗粒铜粉之间的间隙大，改性聚甲醛可以深埋在大颗粒铜粉的间隙中，使改性聚甲醛工作更可靠。

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。