环纹滚刀可以实现高效率的径向进给滚齿加工。
A force transducer was designed to measure the pulling force by which the strands were withdrawnduring upcasting.
根据高温状态下铸坯合金的流变力学行为,对摩擦力与铸坯表面质量的关系进行理论分析,推导出铸坯表面环纹尺寸的计算公式。
According to the study on the freshwater algal fossils, such as Pediastrum, Zygnema and Concentricystes, discovered in the Late Pleistocene sediments in the continental shelf of the Huanghai Sea, the East China Sea and the South China Sea, this paper inferred the changes of sea level, shoreline and continental shelf.
通过对我国黄海、东海、南海陆架晚更新世沉积物中盘星藻、双星藻、环纹藻等淡水藻类化石的研究,推测了当时海面变化、海岸线变迁,追溯陆架地区沧海桑田的历史,并分析沉积时期湖泊的水域变化,说明对海洋沉积物中盘星藻、双星藻、环纹藻等淡水藻类的研究有深远的古环境意义。
The karyotypes of two species in Colubrinae from Fujian Sanmin were first reported by using the method of directly preparing chromosome with marrow cells, and they were found as : Natrix aequifasciata 2n =40,16(1M+5SM+2ST+8T) ·24m(♀); Sexual dimorphism of the chromosomes was represented by No 4 with ZZ/ZW mechanism, showing female heterogamety.
以骨髓细胞直接制备染色体标本, 首次报道了游蛇属的环纹游蛇 (Natrix aequifasciata)和白环蛇属的黑背白环蛇 (Lycodon ruhstrati) 的核型, 其中黑背白环蛇的核型为国内白环蛇属核型首次报道。
Suppose that h ≥1, min{n1,n2,…,nh+1}=m≥3 H1= Pn1, ×… × Pnh+1 is a grid and H2 = Cn1, ×…×Cnh+1, is a torus.
本文的主要结果如下:设H≥1,min{n1,n2,…,nh+1}=m≥3,p=ni,H1=Pn1×…×Pnh+1是个格子图, H2= Cn1×…× Cnh+1是个环纹面, t(H)表示 H的支撑树数,则,这