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运用生精上皮周期理论,以定量组织学方法,结合采用电镜组化技术,观察了~(60)Coγ射线全身照射大鼠后睾丸生精上皮、曲细精管界膜和界膜内碱性磷酸酶的改变。探讨了~(60)Coγ射线对生精上皮的损伤特点,曲细精管界膜内碱性磷酸酶的辐射敏感性,以及界膜和界膜内碱性磷酸酶与生精上皮在辐射损伤、修复中的相互关系。结果显示,分化型精原细胞对辐射最敏感;4Gyγ射线全身照射后,大鼠生精上皮仍可恢复,幸存的耐辐射精原干细胞是修复上皮的唯一来源;支持细胞超微结构随照射后生精细胞数量的减少而改变;照射后界膜明显增厚、分层、皱折;界膜内碱性磷酸酶的辐射耐受性较高,受照后12天碱性磷酸酶反应产物明显减少,其恢复早于生精上皮的修复。  相似文献   
2.
缩短电镜生物样品制备时间,以适应临床工作的需要一直是电镜工作者努力的方向,微波辐射应用于扫描电镜样品的制备,可缩短制样的时间,我们参考有关文献,并在此基础上加以改进,用微波辐射,叔丁醇脱水干燥,不仅可以缩短制样时间,还可以减少对细胞样品表面结构的损伤。  相似文献   
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The pre-ionized 60 MHz very-high-frequency (VHF) magnetron discharge at low pressure, assisted by inductively coupled plasma (ICP) discharge, was developed. The measurement of ion flux density and ion energy to the substrate was carried out by a retarding field energy analyzer. The electric characteristics of discharge were also investigated by voltage–current probe technique. It was found that by reducing the discharge pressure of VHF magnetron discharge from 5 to 1 Pa, the ion flux density increased about four times, meanwhile the ion energy also increased doubly. The electric characteristics of discharge also showed that a little improvement of sputtering effectiveness was achieved by reducing discharge pressure. Therefore, the deposition property of VHF (60 MHz) magnetron sputtering can be improved by reducing the discharge pressure using the ICP-assisted pre-ionized discharge.  相似文献   
4.
The effect of radio-frequency substrate bias on ion properties and sputtering behavior of 2 MHz magnetron discharge was investigated. The ion velocity distribution function(IVDF), the maximum ion energy and ion flux density were measured at the substrate by a retarding field energy analyzer. The sputtering behavior was investigated by the electric characteristics of target and bias discharges using voltage–current probe technique. It was found that the substrate bias led to the decrease of sputtering power, voltage and current with the amplitude 7.5%. The substrate bias also led to the broadening of IVDFs and the increase of ion flux density, made the energy divergent of ions impacting the substrate. This effect was further enhanced by increasing bias power and reducing discharge pressure.  相似文献   
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