淬硬精密丝杠的牙形精度取决于精磨。
The accuracy of the tooth forms of the quenched precision lead-screws is decided by the precise grinding.
牙形刺的分布主要与平静的暖水大洋有关。
The Precordilleran conodonts are mainly related to a calm and warm-water ocean.
加工的挤压螺纹表面有一层纤维沿其牙形连续分布。
The microstructure of the thread machined by form tapping showed a layer of fine fiber distribution along the thread profile.
本文还讨论了该区牙形刺颜色变化对油气勘探的意义。
Besides, the colour alteration of conodonts and its significance in exploring oil and gas is als...
牙形刺在三叠纪末期灭绝了,这正是恐龙开始演化的时代。
Conodonts went extinct at the end of the Triassic Period, about the time dinosaurs were evolving.
金刚石笔修整砂轮误差使滚道在磨削时产生非圆牙形误差。
The errors of grinding wheel dressed by diamond point cause the race to produce non-circular arc tooth profile errors.
牙形刺;晚石炭世;本溪组;辽宁东南部;地层划分与对比。
Conodonts; Late Carboniferous; Benxi Formation; southeastern Liaoning; Stratigraphical divisions and correlation.
古生物学论文,83,中国南方长江三角洲志留纪时期牙形刺研究。
Special Papers In Palaeontology, Number 83, Silurian Conodonts From The Yangtze Platform, South China ( )
牙形刺最早出现于大约5亿年前,就在恐龙开始登上历史舞台时灭绝了。
Conodonts first emerged around 500 million years ago and died out just as dinosaurs were beginning to take shape.
贵州罗甸纳水剖面是研究宾夕法尼亚亚系牙形刺和各阶界线的良好剖面。
The Nashui section of Luodian, Guizhou is a good section for the study of the Pennsylvanian conodonts and the stage boundaries.
本文对深海硅质岩系中这一界线地层牙形石动物群特征进行了简要的描述。
We also concisely described the characteristics of the conodont fauna through the boundary strata.
主要的生物化石发育于台地相灰岩中,包括蜓类、牙形石等个体较大化石;
Main oryctocoenose preserved in limestone of platform facies includes various types of large bodies, such as Schwagerina subnathorsti(Lee), S. sp.
牙形刺生活在寒武纪的海洋中,可能以某种浮游生物为食,不过没人清楚具体情况。
Conodonts lived in the Cambrian seas, and may have eaten certain types of plankton, but no one knows for sure.
对这4个阶段的牙形石动物群和华北、华南同期牙形石动物群进行了详细的对比。
In this paper, a detailed comparison is made between the four phases in the Tarim Basin and the corresponding faunas in South China and North China.
本文介绍一种测量石油螺纹量规的螺旋线、中径、锥度和牙形半角的新方法及装置。
This paper describes a new method and device for measuring helical line, pitch diameter, taper and half-angle of thread of petroleum thread gauges.
通过牙形石生物相分析,推断温古尔地区中二叠世早期可能为盆地相较深水沉积环境。
Based on an analysis of the conodont biofacies, it is inferred that there was probably a deep-sea basin facies sedimentary environment in the Wenguer area during the early Middle Permian.
这种叫作牙形刺的动物长有数排相互咬合的圆锥状利牙,像钉耙一样将猎物“耙”入口中。
The animals, called conodonts, possessed rows of sharp, interlocking cone-shaped teeth that raked prey into their mouths.
对江西省信丰县铁石口剖面晚二叠世长兴阶至铁石口阶下部的牙形石动物群有了新的认识。
A detailed research has been worked on the Late Upper Permian conodont fauna of Tieshikou section in Xinfeng area, Jiangxi Province.
另一方面,NPTF螺纹的设计用于保证在整个牙形上产生足够的变形以生成这种机械密封。
On the other hand, NPTF threads are designed to ensure that sufficient crushing of the entire thread form will take place to produce a mechanical seal.
首次描述并图示了位于华北地台和华南地台之间的秦岭山脉中的早石炭世杜内阶上部的牙形刺。
Late Tournaisian conodonts from the Jiehejie Formation in the Qinling Mountains, situated between the North China Platform and South China Platform are first described and illustrated in this paper.
英国古生物学家们通过牙形石动物的软体解剖学研究,发现眼睛、脊索、神经索、肌肉组织、尾鳍等软组织;
The soft anatomy of conodont shows some soft tissues including eyes, notochord, nerve cord, myomeres and caudal fin.
介绍了常见的用于紧固联接英寸制螺纹和用于管道连接英寸制螺纹的牙形、配合和标识,以及管螺纹的密封特点。
The tooth shape, fit and mark of clamping connection and pipe connection inch threads commonly used are introduced and their seal features.
介绍了一种大导程波形联结螺纹的高效加工方法,借助计算机进行了螺纹牙形的精度分析,得出了齿形误差曲线。
This paper presents a high efficient process method of a steep lead tread of coupling screw and studies the profile accuracy by using electronic computer and arrives at the profile error curve.
可能是因为周末是万圣节的关系,上面的图片让我联想到了下面的画面。想象一下,头发不是蛇而是牙形刺的美杜莎。
It might be due to the Halloween weekend, but the above reminds me of the below image. Imagine if Medusa had conodonts instead of snakes.
然而,这些结论是通过对高度进化的真牙形石属的研究获得的;它们在多大程度上代表了原始真牙形石还存在疑问。
However, this conclusion was based on the evidence from some highly derived euconodont taxa; the degree of their plesimophic to basal euconodonts still remains in question.
牙形刺之所以仍然如此神秘,一个原因就是除了发现过它们的牙齿化石以外,它们柔软的躯体无法变成化石保存到今天。
One reason why conodonts have remained so enigmatic, despite the fossil finds, is that their soft bodies didn't leave much to make fossils.
不过,在20世纪80年代,古生物学者发现了完整的牙形刺化石标本,而直到最近科学家们才开始揭露出它们的秘密。
In the 1980s, however, paleontologists found full fossilized conodont specimens, and only recently have scientists begun to unravel their secrets.
本文从方牙丝杠磨削的原理误差入手,分析了方牙丝杠加工的原理性误差及其对工件牙形精度的影响程度,提出了减小加工方牙丝杠原理误差的措施。
The paper analyzes machining error and its effect on the tooth profile accuracy according to the principal error, and gives the methods to diminish the error.
本文从方牙丝杠磨削的原理误差入手,分析了方牙丝杠加工的原理性误差及其对工件牙形精度的影响程度,提出了减小加工方牙丝杠原理误差的措施。
The paper analyzes machining error and its effect on the tooth profile accuracy according to the principal error, and gives the methods to diminish the error.
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