圆和

Grinding wheel is usually mounted on surface grinding machine, external circular grinding machine and internal circular grinding machine, and can also be mounted on grinding wheel machine, knife grinder and universal cutter grinder for grinding of cutting tool. According to different functions, grinding mode and type of grinding machine, grinding wheel is manufactured into ones with all kinds of shapes and sizes, and common grinding wheel includes plane grinding wheel, cylinder grinding wheel, double hypotenuse grinding wheel, cup grinding wheel, flaring cup wheel, disc wheel, centerless grinding wheel, etc. The types of products include external circular, plane and centerless grinding wheels used for fine and rough grinding machining of t

公司的产品类型有用于钨钢硬质合金的精粗磨削加工的外圆磨、平面磨、无心磨砂轮；有用于陶瓷、氧化锆白陶瓷、黑陶瓷行业的CBN/SDC金刚石平形砂轮、精密切割片、平行加强形砂轮和开槽电镀磨头；用于钢化玻璃，灯饰玻璃，水晶玻璃，磁性材料行业的CBN/SDC金刚石精密切割片，青铜磨盘，青铜切割片，平行双粒度磨盘和小磨头，深加工行业的CBN电镀和烧结磨轮、抛光磨盘；用于高速钢，45#钢的剪刀、锯片、刀片的精粗加工，用于加工硅片材料、铁氧体及其他材料的金刚石工具；以及其他行业需要的各种要求的非标金刚石工具。

In the paper, on the basis of aggregation of previous studies, the development of optical technology and development trends at home and abroad are introduced, the principle of Fresnel lens is summarized. In accordance with its principle, circle equidistant steps Fresnel lens design is described. And on this basis, based on Fresnel design, also based on a continuous upward spiral of the plane curve concept, incidence surface and the backlight is set up to greet Archimedes - Fresnel lens design formula and the Second parabolic type Fresnel lens design formula, and on this basis, the advantages and disadvantages of the three designs is discussed.

本文在充分了解非球面光学技术在国内外的发展状况和趋势的基础上，同时从菲涅尔透镜的光学原理出发，并根据它的工作原理推导了圆环等距菲涅尔透镜的设计步骤，并在此基础上依据菲涅尔的设计思想，同时依据平面曲线的连续又呈螺旋的构思，推导出了迎光面和背光面阿基米德型菲涅尔透镜的设计公式和二次抛物面型菲涅尔透镜的设计公式，并在此基础上讨论了这三种设计各自的优缺点。

This design firstly fixed on design scheme and selected basic components, and besides, developed the reliability analysis of transmission system. The design of MG300/701-WD Shearer's cutting unit. It is made up of a gearbox and moderate breeze gear wheel transmission that the MG300/701-WD type mining machine cuts the cutting department, Cut the electrical machinery of cutting department and put to fix up horizontally in the rocker arm, The power that the motor outputs leans on a round of transmission of department of gear wheel and planet round via the tertiary straight tooth, Urge the cylinder to rotate finally.

本文首先确定了设计方案和选择了基本部件并开展了传动系统的可靠性分析，MG300/701-WD型采煤机截割部主要是由一个减速箱和四级齿轮传动组成，截割部电机放在摇臂内横向布置，电动机输出的动力经由三级直齿圆拄齿轮和行星轮系的传动，最后驱动滚筒旋转。

The single and combined toxicity effects on Paramecium caudatum, Dugesia japonica and Cipangopaludia cathayensis exposed for special period (12, 24, 48 and 72h) in different Pb(superscript 2+) and Cd(superscript 2+) concentrations were studied by using toxic experiment techniques.

在特定时间(12、24、48、72h)内，研究了Pb(上标 2+)和Cd(上标 2+)对草履虫、三角涡虫和中华圆田螺3种水生动物的单一和联合毒性效应。

This design firstly fixed ondesign scheme and selected basic components, and besides, developedthe reliability analysis of transmission system. The design ofMG300/701-WD Shearer's cutting unit. It is made up of a gearbox andmoderate breeze gear wheel transmission that the MG300/701-WD typemining machine cuts the cutting department, Cut the electricalmachinery of cutting department and put to fix up horizontally inthe rocker arm, The power that the motor outputs leans on a roundof transmission of department of gear wheel and planet round viathe tertiary straight tooth, Urge the cylinder to rotate finally.

本文首先确定了设计方案和选择了基本部件并开展了传动系统的可靠性分析，MG300/701-WD型采煤机截割部主要是由一个减速箱和四级齿轮传动组成，截割部电机放在摇臂内横向布置，电动机输出的动力经由三级直齿圆拄齿轮和行星轮系的传动，最后驱动滚筒旋转。

During this process, the spherical polar coordinate transformation and the circle polar coordinate transformation are used to carry on the pretreatment for the historical data about investment ratio and investment accumulation rate of the three industrial sections, and the consequent data also be simulated by statistical software-SPSS12.0; Finally, sensitivity analysis according to investment ratio and the fixed assets investment accumulation rate of the three industrial sections are made and a better resource distribution plan for the three industrial sections also be given.

在预测的过程中，利用球面极坐标变换和圆极坐标变换分别对三次产业投资比例和积累率的历史数据进行预处理后，再利用统计软件SPSS 12.0进行拟合；最后，利用固定资产投资的积累率和三次产业的固定资产投资比例进行灵敏度分析，提出了一个较好的三次产业经济的资源分配方案。

The porine is the polyembryony animal, many obtains the ovocyte from the porine ovary although but the maturity quite to be low; Because the ROSI technology is does not have to grow the mature sole round sperm cell to pour into directly completely in the ovicell nature, jumped over the spermatozoon in to pass through the physiology and the biochemistry, if the ovicell nature mature or the activation degree were insufficient, added the round immature sperm cell maturity quite inferior reason, very possibly Causes the ROSI micro fertilization defeat.

猪是多胎动物，从猪卵巢上获得的卵母细胞数量虽然较多，但成熟度比较低；由于ROSI技术是将没有完全发育成熟的单一圆形精细胞直接注入卵胞质内，跳越了精子在穿过透明带和卵质膜等过程中所发生的生理和生化反应；如果卵胞质成熟或活化程度不够，加之圆形未成熟精细胞成熟度比较差等原因，很可能造成ROSI受精的卵母细胞内部激活因子蓄积减少和生成不足，引起精核解聚困难、精圆核不能形成、第二极体不能排出、卵母细胞孤雌发育率增加等，使ROSI显微受精失败。

Vesic's solutions to cavity expansion that include cylindrical cavity expansion and spherical cavity expansion are introduced. Then cylindrical cavity expansion theory is applied to study compaction effect of pile driving in saturated soil. Based on the results of conventional triaxial tests, a trilinear curve model is used to simulate stress-strain curve of strain-softening materials. Meanwhile, trilinear curves are also used to simulate curves of volumetric strain, minor principal strain and major principal strain. By using elasto-plastic theory, analytical solutions to cylindrical cavity expansion in strain-softening soil are presented. According to the mechanism of statically pressed pile driving, compaction effect of pile tip can be viewed as hemispheric cavity expansion. Therefore spherical cavity expansion theory is applied to obtain the solutions to stress, strain, displacement fields and final pressure. Resistance force of pile tip is calculated to estimate static pressure.

介绍了Vesic关于圆孔扩张问题的解答，其中包括柱形孔扩张问题和球形孔扩张问题，并应用柱形孔扩张理论分析了饱和软土中的沉桩挤土效应问题；在常规三轴试验成果的基础上，采用三折线模型模拟具有应变软化性质的岩土材料的应力应变关系曲线，分析了在应变软化土体中沉桩时桩周土的位移场、应力场和应变场的变化，得到了解析解答；分析了静压桩的沉桩机理，并利用球形孔扩张理论，视桩端处的挤土为半个球形孔的扩张，分析了桩端处土的位移场、应力场和应变场的变化，并根据最终扩张压力计算出沉桩时的桩端阻力，可作为压桩力的估算。

The distribution of SYP and the ultrastructures of SYP immunoreactive cells and immunoreactive products in intercellular space of the sacculus rotundus of rabbits were investigated using immunohistochemistry and immune electron cytochemistry methods.

采用免疫组化和免疫电镜细胞化学的方法，对家兔圆小囊组织中的SYP阳性细胞和胞间阳性反应物的光镜和电镜超微结构特点进行了研究。

The ultrastructures of the SP, VIP secretory cells showed there were several kinds of cells with different morphology which could express these neuropeptides in sacculus rotundus.

免疫电镜细胞化学观察发现在兔圆小囊内除了DNES等细胞内有SP和VIP的分布以外，在细胞间隙和淋巴细胞、巨噬细胞等的胞浆膜上也常见SP和VIP免疫电镜阳性反应信号。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。