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101.
DJ Li K Ohsaki K Ii Q Ye Y Nobuto S Tenshin T Takano-Yamamoto 《Canadian Metallurgical Quarterly》1997,111(8):702-706
The present study evaluates histological characteristics of the soft tissue response to long-term implantation of Apaceram discs composed of dense hydroxyapatite in rats. Discs were implanted into the subcutaneous tissue of 76 rats for six to 20 months. Decalcified histological sections stained with haematoxylin and eosin (H & E) and Mallory's azan were examined. Different cell types surrounding implants were counted. The greatest proportion of macrophages was found at six months (13.5 per cent). This proportion gradually decreased to four per cent at 20 months. Small numbers of lymphocytes and foreign body giant cells were observed in every group, but neither neutrophils nor osteogenesis were observed in any specimens. Results of the present study and previous related studies indicate that despite reappearance of a small number of macrophages six months after implantation, Apaceram is useful for reconstructive surgery. 相似文献
102.
研究了铁钴钒软磁合金的铁芯损耗,发现铁芯损耗谱具有分形结构。讨论了带材厚度和磁感应强度对分形维数Df的影响。 相似文献
103.
104.
Ye. L. Stolov 《Journal of Electronic Testing》1993,4(3):283-283
Let a circuit havem outputs,m>1. There are two ways to test this circuit by means of a signature analyzer: use a single input analyzer for each output or use anm-input analyzer to test all outputs simultaneously. The main goal of this letter is to demonstrate that for fault output sequences with small multiplicity of errors and long length the second approach is more effective. 相似文献
105.
A damage identification technique for CF/EP composite laminates using distributed piezoelectric transducers 总被引:8,自引:0,他引:8
In this study, a damage identification approach was developed for carbon fibre/epoxy composite laminates with localized internal delamination. Propagation of the Lamb wave in laminates and its interaction with the delamination were examined. The fundamental symmetric Lamb wave mode, S0, and the lowest order shear wave mode, S0′, were chosen to predict damage location. A real-time active diagnosis system was therefore established. This technique uses distributed piezoelectric transducers to generate and monitor the ultrasonic Lamb wave with narrowband frequency. The two-way switches were employed to minimize the number of transducers. A signal-processing scheme based on the time–frequency spectrographic analysis was utilised to extract useful diagnostic information. Also, an optimal identification method was applied on damage searching procedure to reduce errors and obtain the diagnostic results promptly. Experiments were conducted on [0/−45/45/90]s CF/EP laminates to verify this diagnosis system. The results obtained show that satisfactory detection accuracy could be achieved. 相似文献
106.
运用电子显微分析和波谱分析等方法对GH2027合金的第二相进行了研究,结果表明,合金晶界相主要是片状M6C和薄膜状M23C6,经波纹图样测得其错配度约为3%,晶内M6C和M23 相似文献
107.
泥浆制备中工艺改造的研究 总被引:1,自引:0,他引:1
根据室条件下粉磨试验结果,发现球磨过程中筛上料变化存在的突变范围,提出两次加料一次加水可改变泥浆颗粒分布,并找出适宜的加料种类与时间。另外给予测粒度分布提供了宝贵的试验基础数据。 相似文献
108.
109.
In order to conduct in vivo continuous monitoring of blood gas levels, very thin disposable pO/sub 2/, pCO/sub 2/, and pH sensors, which could be incorporated into a syringe needle or a catheter, were microfabricated. Electrode patterns were formed on a polyimide substrate and stacked with intervening polyimide insulating layers. An electrolyte layer was formed, which was covered with a silicone rubber gas-permeable membrane or a passivating layer. The most critical part of the sensor was a Ag-AgCl reference electrode with a pinhole structure. Because of the structure and novel operational mode of the reference electrode, its potential stabilized immediately, and reproducible responses were realized for the respective sensors. Performance characterization revealed clear responses and linear calibration plots in the ranges of partial pressures or pH of physiological levels. No significant damages or changes in the performance of the sensors were observed after ethylene oxide sterilization. 相似文献
110.
通过现场考察、原型观测和有限元计算,分析了拦污栅断裂的原因,提出了技术改造的建议. 相似文献