| 1. | The algorithm is also extended to three dimensions , and 3 - d contact type model are derived using ball element
本文还将该方法扩展到三维，推导出基于圆球单元各向同性的三维离散元连结型计算模型。 |
| 2. | The department has introduced measures to reduce waste by economizing use of paper , forms and envelopes as well as using ball - point pen refills and reuse paper clips
本局推出了多项措施，藉节约使用纸张、表格和信封，以及使用原子笔替换笔芯和循环再用曲别针来减少废物。 |
| 3. | Based on analyzing the loss because of scattering of thickness of vertical micro - mutor , this dissertation brings forwards the package method of using ball - lens and v grooves to align fibers
在此基础上，对光开关的耦合封装进行了试验。对由于工艺的离散性造成微镜厚度对光纤封装耦合产生的损耗进行了分析。 |
| 4. | Ball valve uses ball with circular hole as open - close part , through turning ball with stem to realize on - off movement . ball valve is mainly applied to stop , distrubute and change flowing direction of medium
球阀是用带圆形的通孔的球体作启闭件，球体随阀杆转动，以实现启闭动作的阀门，球阀在管道中主要用于切断，分配和改变介质流动方向。 |
| 5. | Amorphous can be obtained at certain composition range using ball milling . the size of the amorphous particles decreases with the lengthening of milling time , and reaches several nanometers . experiment also shows that the mixture powder is well ferromagnetic
实验发现，在一定成分范围内通过球磨可以获得非晶，非晶粉末颗粒大小随球磨时间的延长而减小，最终达到几个纳米；同时发现，该混合粉末具有良好的铁磁性。 |
| 6. | In chapter two , we fabricated r - ni - fe / al2o3 nanocomposites successfully by using ball - milling mixing method plus hot - pressing process . meanwhile , their microstructures are characterized by x - ray diffraction ( xrd ) analyser , transmission electron microscopy ( tem ) , field emission scanning electron microscopy ( fe - sem ) and brunauer - emmett - teller ( bet ) . the results indicate that ni - fe particles are homogenously dispersed in the matrix in the composites
在第二章中，我们采用高能球磨混合方法加上热压烧结工艺，成功制备了ni - 20fe al _ 2o _ 3纳米复合材料，并通过x射线衍射仪( xrd ) 、透射电镜( tem ) 、场发射扫描电镜( fe - sem ) 、比表面孔隙仪( bet )对该复合材料的微结构进行了表征。 |
| 7. | Nano - si embedded sio2 composite thin film were fabricated by using ball - milling and sol - gel technology , it is found that the red pl band located at about 730nm is affected by the interface characteristic of nano - si , this indicated that the red emitting resulted from nc - si is also rely on its interface characteristic
采用球磨与溶胶凝胶法结合制备了sioz镶嵌纳米出复合薄膜，发现位于刀on附近的红光发射带受纳米颗粒界面的影响，说明起源于硅纳米颗粒的红光发射依赖于界面特性。 |
| 8. | As a highly efficient and succinct scheme , the subdivision surface has been widely used in the field of computer graphics and 3d surface modeling . to extend its application in industry , the tool path generation algorithm and simulation for 3 - axis nc machining of the subdivision surface model is studied . two interference - free tool - path generation algorithm using ball - end mills in 3 - axis machining are developed
递归分割曲面建模方法因为其简洁、高效等特点广泛应用于计算机图形学和曲面造型等领域,为了推广它在工业中的应用,本文研究递归分割曲面模型的数控加工刀位计算及仿真,实现三坐标球头刀数控加工的刀具轨迹生成和加工过程仿真,并对加工结果进行误差分析。 |
| 9. | The surface oxidation of the composite particles , breakage of the composite particles using ball milling or the addition of span - 80 when synthesized may reduce the permittivity of the composite particles , but the surface oxidation may also reduce the imaginary part of the permeability of the composite particles
使复合粒子表面氧化，球磨破碎复合粒子或在制备- fe粒子时添加span - 80均可以降低复合粒子的介电常数，但复合粒子表面氧化同时使粒子磁导率虚部也有较大降低。 |
