聚甲醛

In case of cold that the crystallization is accompanied by generation of side effects paraformaldehyde, and for non-reversible reaction.

如遇冷即结晶，同时伴随有生成多聚甲醛的副反应，且为不可逆反应。

The preparation,amount of promoters used in synthesis of paraformaldehyde with low polymerization degree were studied.

考察了制备低聚合度多聚甲醛的适宜助剂、加入质量分数和效果，并研究了反应时间、反应温度和热空气线速度对制备的PF中醛质量分数和醛收率的影响规律。

Those compounds were prepared by means of the Mannich reaction from the correspondingthiochromanone,amine and paraformaldehyde.

这些化合物是用相当的酮、胺类盐酸盐与聚甲醛进行 Mannich 反应制得。

In this paper,the expandable phenolic resin was synthesized by paraformaldehyde and phenol in the presence of aqueous NaOH.

以多聚甲醛和苯酚为原料，合成了适用于酚醛膨胀体制备的酚醛树脂。

MOCA is prepared with o-chloroaniline and paraformaldehyde as materials.

以邻氯苯胺和多聚甲醛为反应原料制备MOCA。

The effects of three different fixatives （including paraformaldehyde, glutaraldehyde and the mixture of the two） and time of storage on the determination of picoplankton are compared.

对比了用流式细胞术现场测定及用多聚甲醛、戊二醛及两者的混合物这三种常用固定剂进行固定保存对微微型浮游生物样品的影响。

Result The spindles of oocytes were abnormal at 25℃ for 20 min, and disappeared at 25℃ for 30 min or at 4℃ for 10 min. 5, 10, 20 and 40 μg/ml Cytochalasin B for 2 h had no effects on the spindles of the oocytes. The spindles of oocytes were abnormal in 20 μmol/L colchicines for 1 h, and disappeared in 40 μmol/L colchicines for 1 h. The structure of spindles were perfect for 1-12 h when the oocytes were fixed in 4% paraformaldehyde.

结果］卵母细胞在25℃、20 min时纺锤体异常，25℃、30 min或4℃、10 min时纺锤体缺失；5、10、20和40μg/ml细胞松弛素B作用2 h未对纺锤体产生影响；卵母细胞在20μmol/L秋水仙素中作用1 h纺锤体异常，40μmol/L时作用1 h纺锤体缺失；在4%多聚甲醛中4℃条件下，卵母细胞纺锤体结构以固定时间为1~12 h效果较好。

The thermoset phenolic resin was synthesized by all the waste water from the former process, paraformaldehyde and phenol.

以上述热塑性酚醛树脂生产中排放的全部废水、多聚甲醛、苯酚为原料可以合成多种用途的热固性酚醛树脂。

Methods: P-toluenesulfonic acid diethoxyphosphorylmethyl ester (4) was prepared from diethyl phosphate and paraformaldehyde by condensation and esterification.

以亚磷酸二乙酯和多聚甲醛经缩合、酯化得到对甲苯磺酸羟甲基磷酸二乙基酯(4)。

Methods Healthy male SD rats of different age groups were recruited(1-, 2- and 3- week groups, 1- and 2- month groups, 6- month grown group, and 18- month aged group; n=5 each). Immunohistochemistry was performed on the coronal sections of brain of the rats perfused with paraformaldehyde.

健康雄性SD大鼠，分为7天、2周、3周、1月、2月、成年（6月龄）和老年（18月龄）7组，每组5只，共35只，多聚甲醛灌注固定，冰冻冠状切片，免疫组织化学染色，光镜观察摄像，细胞计数。

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。