1.周率,频率;【电】周波;【医】定期发作;【天】定期出现;【化】周期表中的位置
2.定期[周期]性;间发性;周期数
1.recurrence at regular intervals
2.similarity between the properties of chemical elements that are close to each other in the periodic table
1.The research resultsshowedthat the population density of rodents fluctuated obviously among different years, but there was no periodicity.
研究结果表明，不同年间啮齿类种群密度波动明显，但无周期性；
2.The finely grounded PAA was crystal polymer and its structure unit arranged periodicity with a little crystal lattice disfigurement.
分离得到的PAA为结晶聚合物，结构单元呈周期性排列，但存在一定的晶格缺陷。
3.It was analyzed how the photonic crystal periodicity and liquid thickness affect the Q value of the sensor.
文章分析了传感器Q值与光子晶体周期数及被探测液体厚度之间的关系。
4.The former repulses all the way and the repulsive forces are weaker than those of bright solitons. They have no periodicity, either.
而后者从一开始就相互排斥，且这种排斥作用较亮孤子来说相当微弱，同样也不具有周期性。
5.The suddenness, contingency and periodicity of its occurrence were explored and suggestions about the forecast of the pest were made.
探讨了发生的突发性、偶然性、周期性，并对该虫的调查测报等工作提出了建议。
6.The utility model has the advantages of low cost, short manufacture periodicity and one-step forming for the side wall of the car.
使其与现有技术相比，具有成本低，制作周期短，使轿车侧围能一次成型的特点。
7.The treatments varied because pelvic sores occurred repeated without any periodicity and symptoms were different due to various causes.
以非周期性反复发作的盆腔疼痛为特点，不同疾病引起的疼痛体征不尽相同，治疗方法也不同。
8.Regular irregularities occur with constant periodicity and are usually associated with partial heart block.
规律的不整脉随固定周期出现，而且常伴有心脏部分传导阻滞。
9.The enterprise has high similar characteristic to the biology in growth, competition, environment adaptability and periodicity etc.
企业具有与生物高度相似的成长性、竞争性、环境适应性、周期性等特征。
10.The redshift periodicity is evidence for past oscillations in the expansion rate of the universe. . .
该红移的周期性是过去宇宙膨胀速率变化的证据…