圆

Pitch is a combination number of a one-to-two ratio indicating the spline proporti******; the upper or first number is the diametral pitch, the lower or second number is the stub pitch and denotes, as that fractional part of an inch, the basic radial length of engagement, both above and below the pitch circle.

径节分数：径节分数是由两个数组成的一个比率，它表示的是花键的比例；设这个比率为A/B，则在这个分数中第一个数A表示的是花键的径节，第二个数B表示的是残余径节，径节表示的是在节圆上方的键齿在半径方向上的结合长度，残余径节表示的是在节圆下方的键齿在半径方向上的结合长度。

Tooth Proportions.—There are 17 pitches: 2.5/5, 3/6, 4/8, 5/10, 6/12, 8/16, 10/20, 12/24, 16/32, 20/40, 24/48, 32/64, 40/80, 48/96, 64/128, 80/160, and 128/256. The numerator in this fractional designation is known as the diametral pitch and controls the pitch diameter; the denominator, which is always double the numerator, is known as the stub pitch and controls the tooth depth. For convenience in calculation, only the numerator is used in the formulas given and is designated as P. Diametral pitch, as in gears, means the number of teeth per inch of pitch diameter.

齿比——一共有17种齿比：2.5/5，3/6，4/8，5/10，6/12，8/16，10/20，12/24，16/32，20/40，24/48，32/64，40/80，48/96，64/128，80/160和128/256在这一系列的分数中的分子是径节，径节的大小决定了节圆的直径；而分数中的分母通常是分子的两倍，分母是残余径节，它的作用是控制齿槽的深度为了方便计算，在所有的公式中都使用分子作为计算参数，并且与齿轮的表示方式一样定义为径节P尺寸，也就是在节圆上，每英寸长度上的齿数

Why?" I questioned in puzzle ment . He smiled and drew a circle on a piece of paper, then made a dot in its circumference and asked me,"Which way is the shortest to reach the symmetrical dot in the circumference from this point?""Diameter , I responded , and with this answer I suddenly realized that I was lucky enough to live a diametrical life , namely, a very smooth life . Since I exposed myself to the research in materials, I have been aspir ing to become a scientist, and God has blessed me with a diametrical life without any waste of time or life.

我问父亲，父亲微笑着拿起手中的圆规在白纸上画了一个圆，在圆周上点下一点，问我道："在同一个圆上的一点到达与之相对称的另一点，什么样的方式是最快的呢""直径"，当答案从我的嘴中脱口而出之时，我猛然间也明白了我的幸运就在于我的直径人生，从我进入物理的领域到今日希望成为一名杰出研究者的理想，上帝让我幸运的获得了走这条直径的机会，没有浪费时间和生命。

The environmental pollution and operation question which comes from ammonium dichromate as photosensitizer was overcome by this sensitive material.

这种以重氮树脂为光敏剂的圆网感光材料克服了目前以重铬酸盐为光敏剂的圆网感光材料所存在的操作问题及环境污染问题。

Dihyborid An organism that is heterozygous at two loci, formed by crossing homozygous parents with different alleles at two given loci: for example, Mendel ' s cross between yellow round and green wrinkled garden peas to give a yellow round dihybrid.

双因子杂交：用两个基因位点上具有不同等位基因的纯合亲本杂交形成的杂合生物体。例如，在孟德尔的杂交试验中，黄圆和绿皱杂交生成杂合子黄圆。

The Fresnel lens, also known as the dioptric lens, consists of a central glass disk and concentric glass rings or a central glass band surrounded by parallel glass rings.

一个在中心的玻璃圆片和与之同圆心的层层玻璃圆环，或者中间是一个玻璃带，两边是与之平行的玻璃带状环。

The disk used in a disc brake.A disk used on a disk harrow.

圆盘耙片；圆盘农具用在圆盘耙上的圆片

The company mainly produces a variety of machines with disk plow, disc harrow, agricultural disc, tillage spade, hoe teeth, and other farming machinery and accessories.

公司主要生产各种规格的机引圆盘犁、圆盘耙、农用圆盘、松土铲、锄齿等耕作机械及配件。

In this paper, the development situation and level of driving disk plow at home and abroad are introduced and their market prospects are analysed. A proposal of further developing the products of driving disk plow in China is put forward.

本文介绍了驱动式圆盘犁的国内外研制情况与水平，并对市场前景作了分析，提出在国内进一步开发有关驱动式圆盘犁产品的建议。

The technical plan in the research on hand tractor attached driving disk plow is expounded with function analysis system technique.

本文从人－机－环境系统出发，综合分析了诸因素之间的内在联系，应用功能系统分析技术，阐述了手扶拖拉机配套驱动式圆盘犁研究过程中有关技术方案，分析了工作偏角α，机组侧向力的平衡、前后圆盘耕深一致等关键技术。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。