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81.
李国栋 《稀有金属材料与工程》2000,10(5):289-292
综述了1998年~199年间若干磁性功能材料研究和应用新进展。其内容包括:(1)磁传感器新材料;(2)六角晶系微波铁氧体材料;(3)大容量自旋阀磁存储器;(4)磁薄带和磁薄膜变压器;(5)大功率应用的铁氧体材料。 相似文献
82.
水基流延制备片式PTCR陶瓷的研究 总被引:1,自引:0,他引:1
采用sol-gel法制备纳米BaTiO3基PTCR粉体,并以其为原料,采用水基流延成型工艺制备片式PTCR。研究了在sol-gel法制备BaTiO3粉体中,施受主元素含量、陶瓷的烧成温度与PTC效应、晶粒尺寸的关系以及水基流延工艺中各种添加剂对浆料和膜片性能的影响。结果表明:以纳米BaTiO3粉体为原料、水基流延的片式PTCR坯片,在1240℃下就能半导化,所得陶瓷样品的升阻比高于104,温度系数大于13%℃–1,平均晶粒尺寸小于2μm。 相似文献
83.
The display image of a PC can be reconstructed by using the conducted emission on the PC's network cable. The relevant signals which be used to reconstruct the original image are coupling from the radiation of the switching of red, green, blue (RGB) signals in PC. These pertinent signals are partly contained in the frequency region higher than 30 MHz in the conducted emission. From these findings, the near-field coupling principle from PC to the network cable is analyzed firstly. And then, a multi-conductor transmission model for the RGB signals which transmit in the network cable is proposed. In addition, the maximum safe distance is estimated by using this model. In order to check the validity of the estimating distance, the eavesdropping experiment is carried out to reconstruct the original display image. The results demonstrate that the blurred display image can be retrieved at the place of 29.5 m. 相似文献
84.
滚轧直螺纹钢筋连接技术的应用和实践 总被引:1,自引:1,他引:0
通过新疆石河子天盛(北区)织染工业园一期一区厂房工程滚轧直螺纹钢筋连接技术的应用,制订了一套完整的施工、质量控制方案,通过实践证明取得了良好的质量经济效果。 相似文献
85.
86.
J. M. Zhao S. L. Ho S. N. Piramanayagam J. Z. Shi 《Quality and Reliability Engineering International》2009,25(3):345-354
For the ever‐increasing recording density in hard disk drives, ultra‐low gliding height media are required. It is an immense challenge for the tape‐burnishing/wiping process of media to reduce the asperities effectively and efficiently while no scratches occur. The purpose of this paper is to characterize and then optimize the tape‐burnishing/wiping process as so to minimize the asperities without leaving any scratches on the media surface. A Taguchi experiment design method is adopted to analyze the data and acquire an optimal level combination of process parameters. The resulting optimal combination is practically implemented in tape‐burnishing/wiping the several magnetic recording media, which reveals that the average pass ratio of 5 nm glide avalanche testing increases nearly doubly to a level of 96%. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
87.
以丁基橡胶为主要原料研制出了丁基橡胶压敏胶粘带,讨论了丁基橡胶、增黏剂、增塑剂和填料用量等对胶粘带性能的影响,研究了其对三元乙丙橡胶防水卷材接缝的粘结作用。 相似文献
88.
In this work, we perform a finite element method (FEM) analysis of the localised thermal quench of a high temperature superconducting (HTS) tape. One 3D thermo-electric coupling FEM model, which is constructed to address the actual development of the localised thermal quench occurred in the HTS tape, has been proposed. One quench experiment is performed to validate this model. It is shown that the mode can quantitatively reflect the dynamic and static quench characteristics when comparing the results of the experiment with the model. The FEM model generates an estimate of the location of the highest temperature and visualisation of the quench dynamics. 相似文献
89.
介绍了八钢金圆钢管公司¢1020mm螺旋焊管机组中双锥头开卷机的备卷、上卷、开卷等结构和性能的改进,改善了开卷机不能满足大吨位钢卷使用的状况,减少了停机时间,提高了工作效率。 相似文献
90.
Y.M. Chong W.J. Zhang Y. Yang Q. Ye I. Bello S.T. Lee 《Diamond and Related Materials》2009,18(11):1387-1392
Cubic boron nitride (cBN) thin films were deposited on diamond-coated tungsten carbide (WC) cutting inserts using electron cyclotron resonance (ECR) microwave plasma chemical vapor deposition (MPCVD). The effects of gas flow rate and substrate bias on the phase composition and structure of the BN films deposited on diamond surfaces were studied. It was revealed that both the cubic phase formation and the selective etching of hexagonal phase were controlled by modulating the hydrogen and boron trifluoride flow rate ratio. By the trial and error method the gas flow rate ratio and substrate bias voltage were optimized. Moreover the phase composition of the BN film was found to be affected by the thickness of diamond buffer layer and interrelated to the effective substrate bias. The hardness of the resulting cBN films reached the value of 70 GPa. In the synthesized coatings, the diamond beneath renders the best mechanical supporting capacity while the top cBN provides the superior chemical resistance and extreme hardness. The cBN/diamond bilayers deposited on WC inserts may serve as universal tool coatings for machining steels and other ferrous metals. 相似文献