焦比

It's just a matter of focal ratio achievable.

这只是可达到焦比的问题。

Though, the lateral resolution of CM has been enhanced to be 1.4 times of that of a conventional optical microscope under the same aperture focus ratio, it is still two orders of magnitude lower than the axial resolution of itself.

然而，尽管共焦显微镜的横向分辨力已提高到相同孔焦比的普通光学显微镜的1.4倍，但与其本身的轴向分辨力相比，横向分辨力仍低2个数量级，因此进一步改善共焦显微镜横向分辨力的研究显得尤为迫切。

He used an SBIG STL-11000M CCD camera at the f/3 prime focus of a 16-inch Cassegrain reflector for a total exposure time of 40 minutes.

他在一台16吋卡塞反射镜f/3焦比的主焦点上装置了一个***CCD，用于总计40分钟的曝光。

The preventive measures for the harmful defects of alkali metals are as follows: 1, reducing the alkali metals content in the raw materials; 2, increasing the MgO content of the sinter , decreasing the basicity of slag , decreasing the Si content of the pig iron, increasing relative slag volume; 3 , introducing prereduced ore pellets or partly reducted sinter; 4increasing the ability of coke resisting alkali metals; 5, using refractories that have the ability of resisting corrasion of alkali metals; 6 , cleaning the blast furnace periodically. The above recommendations are necessary for decreasing the circulation and accumulation of alkali metals effectively in blast furnace, reducing the harmful influence of alkali metals on blast furnace, increasing the smelting intensity, decreasing the coke rate, improving the gas permeability.

基于碱金属对高炉冶炼的上述危害，本文结合湘钢高炉的实际生产情况，通过理论分析、计算以及其他钢厂防治碱害的经验，提出防治高炉碱害的措施：1、减少入炉原、燃料的碱金属含量；2、提高烧结矿中的MgO含量、降低炉渣碱度、降低生铁含硅量、适当增加渣量；3、采用预还原的金属化球团或部分还原的烧结矿；4、提高焦炭的抗碱能力；5采用抗碱侵蚀的耐火材料；6、周期性性洗炉，以有效地减少碱金属在高炉内的循环富集，降低碱金属对高炉的危害，提高高炉的冶炼强度，降低焦比，改善高炉透气性。

In each table I calculated the true field of the eyepiece for a 200 mm (8) f/10 scope.

在每一个表中，我用200mm(8寸)口径，焦比10的望远镜来分析他们的实际视场。

For the mathematically inclinded, the sweet spot's diameter is proportional to the cube of the f/ratio.

从数学计算看，甜点的直径与f/焦比的立方成正比。

The triboelectrostatic beneficiation experiments have been done based on the research of floatability, dielectric constant and mineral components.

在对3种煤的浮沉性能、介电常数、矿物成分研究的基础上，进行了摩擦电选实验研究，应用摩擦电选技术结合喷煤系统的特点，进行炉前降灰具有工艺和技术的合理性，降低高炉喷吹用煤的灰分有利于提高煤比、降低焦比及生铁成本。

Using two symmetrical plano-convex lens system to fabricate grating was analyzed and the characteristic of diffraction wavefront aberration of the grating was summarized by ray tracing program using MATLAB siftware.

分析使用两个对称的单平凸透镜光路制作光栅并用MATLAB编写光线追迹程序分析了所制作的光栅的衍射波像差的特点，经计算得出在较小焦比D/F情况下其衍射波像差仅与两支光路点光源的调节偏差之差有关与单独的各个偏差无关；初级像差中球差很小几乎可忽略：彗差仅与垂轴调节偏差之差成线性关系；像散仅与轴向调节偏差之差成正比；且当平凸透镜的焦比D/F增大时，各像差项迅速增大。

Again we present a spot diagram with the same fields as above except that were changed the focal ratio of our sample parabolic mirror to f/8, doubling the focal ratio.

我们还是用上图，只是改变焦比，把焦比改成F/8

Again we present a spot diagram with the same fields as above except that we抳e changed the focal ratio of our sample parabolic mirror to f/8, doubling the focal ratio.

我们还是用上图，只是改变焦比，把焦比改成F/8

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐