The ultrastructures of the root protophleom sieve element at different developmental stages of Arabidopsis thaliana L.
)根原生韧皮部筛管分子在发育过程中的超微结构变化。
Application of precision micro-pore compound sand control screen pipe in the sand control of Zhou 43 horizontal well;
精密微孔复合防砂筛管在周43水平井应用
Sand control by integral cemented metal fiber screen pipe-III in extra-heavy oil reservoir;
整体烧结金属纤维筛管Ⅲ型防砂技术研究及其在超稠油油藏开采中的应用
Study and application of composite screen liner;
复合式滤砂筛管的研制与应用
The studies include casing running technology, method of casing strength checking out in thermal recovery wells, dimension selection of screen liner and wrapping liner.
在分析新疆克拉玛依油田浅层超稠油油藏地质特点的基础上 ,指出了完井作业的主要难点 ,详细介绍了超稠油水平井完井技术的研究情况 ,包括套管 (尾管 )下入技术、热采情况下套管强度的校核方法、割缝筛管或绕丝筛管的尺寸选择、缝宽选择等。
The paper deals with morphological changes and their mechanisms of two kinds of tracheary elements(tracheids and sieve tubes) in apoptosis in order to provide the bas.
本文根据国内外的研究报道,对两种管状分子(导管、筛管)发育过程中细胞凋亡的形态学变化以及机制进行分析,为进一步探讨细胞凋亡的途径和机制提供参考。
petroleum slotted pipe is a tool for sand prevention in the petroleum production of oil field.
石油割缝筛管是油田采油防砂常用的工具。
The slotted pipe with narrow slots can be mass worked economically and efficiently by means of open loop system and hand automatic model shifter.
采用开环系统和手动、自动模式切换装置，可以经济、有效、大量地加工带有窄缝的割缝筛管。