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排序方式: 共有586条查询结果,搜索用时 15 毫秒
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在分析永磁轴承基本结构的基础上,提出了双环永磁轴承的结构,并进一步分析了该轴承的工作原理和径向偏移承载能力,推导了径向磁吸力、轴承间隙、剩磁之间的关系,经仿真其结果表明:大部分磁力线形成闭合回路,最大限度地减少了磁力线的对外散发,保证了永磁环性能的稳定,延长了永磁环的使用寿命;径向磁吸力随轴承间隙的增大逐渐减小,随表面剩磁的增加而增大;轴承的径向刚度等于长度为半周长的线性模型的刚度。 相似文献
34.
何建伟 《纺织高校基础科学学报》2007,20(1):64-67
把弱Armendariz环的概念推广得到S-弱Armendariz环,讨论了一个环R是S-弱Armen-dariz环的充要条件.进而,得到了R是S×T-弱Armendariz环当且仅当R既是S-弱Armendari环又是T-弱Armendariz环.最后,得到R1×R2是S-弱Armendariz环当且仅当R1和R2均为S-弱Armendariz环. 相似文献
35.
突缘叉耳孔直径尺寸、卡簧槽距尺寸对十字轴弯曲应力、接触应力影响很大,协调确定这2个尺寸可提高万向节寿命.传动轴突缘叉耳孔中心高尺寸,对十字轴总成烧蚀失效有很大影响,通过降低中心高尺寸,减小弯矩对突缘叉两耳的作用,可保证两耳孔轴线的同轴度,保证十字轴总成滚针轴承的径向间隙,降低十字轴总成烧蚀失效率. 相似文献
36.
QH-1型扁环的研究和应用 总被引:11,自引:2,他引:11
介绍了QH-1型扁环的研究和开发。讨论了QH-1型扁环填料的数学模型和设计放大,并举例说明了这种填料的工业应用。 相似文献
37.
P. Pawlus 《Tribology International》1993,26(1)
This paper presents results of the measurement of the surface roughness and other physical properties of the outer layer of honed cylinders. The cylinders tested had various surface topographies as a result of honing by abrasive tools of differing design. The results of wear measurements of the cylinders and piston rings mating with them during automotive gasoline Polonez 1500 engine operation under artificially increased dustiness conditions are presented and analysed. 相似文献
38.
《Ceramics International》2021,47(23):32963-32968
Effects of carbon source in single-source ZrC-based liquid precursors on the properties of the precursors and precursor-derived nano ZrC powders were investigated. The liquid precursors were prepared by directly blending and heating zirconium n-butoxide with either 2,4-pentanedione, benzoyl acetone or 1,3-diphenyl-1,3-propanedione additives which have the same chemical composition and structure except for the number of benzene rings (0, 1 and 2, respectively) in order to control the carbon content in the precursors. The ceramic yield of the precursor decreased as the number of benzene rings in the precursors increased. The stability of the precursors in air and the carbon content of the ceramic powder increased when using 1,3-diphenyl-1,3-propanedione additive. X-ray pure nano zirconium carbide powders with ultra-fine size (30 nm), isotropic shape and homogeneous particle size distribution were synthesized from the liquid precursors containing two benzene rings in the structure. Compared with ZrC powders derived from the precursors containing zero or one benzene ring, the powder from the precursor containing two benzene rings was finer and more homogeneous in size distribution. 相似文献
39.
Computer models of the lubrication of piston-rings in internal combustion engines normally present an estimate of the minimum oil-film thickness between ring and cylinder wall as a function of crank angle. As a consequence, experimental measurements of film thickness play a critical role in the verification of theoretical models of piston-ring lubrication. A review is presented of the wide range of techniques that have been used to measure this important variable. The strengths and weaknesses of particular techniques are identified and a number of ways in which the techniques could be developed further are proposed 相似文献
40.
In analogy to cyclic codes, we study linear codes over finite fields obtained from left ideals in a quotient ring of a (non-commutative) skew polynomial ring. The paper shows how existence and properties of such codes are linked to arithmetic properties of skew polynomials. This class of codes is a generalization of the θ-cyclic codes discussed in [Boucher, D., Geiselmann, W., Ulmer, F., 2007. Skew cyclic codes. Applied Algebra in Engineering, Communication and Computing 18, 379–389]. However θ-cyclic codes are powerful representatives of this family and we show that the dual of a θ-cyclic code is still θ-cyclic. Using Groebner bases, we compute all Euclidean and Hermitian self-dual θ-cyclic codes over of length less than 40, including a [36,18,11] Euclidean self-dual θ-cyclic code which improves the previously best known self-dual code of length 36 over . 相似文献