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61.
Light microscopy was used to study the structure and cellular organization of the osphradial organ of the pulmonary mollusque L. stagnalis. The osphradium unites the epithelial canal and the ganglion consisting of two cell populations. On the internal surface of the V-shaped osphradial canal there are three zones of cells: secretory, villous and epithelial. The villous zone of the canal is related with sensory bipolar and multipolar neurons of the ganglion. The irritation percepted by these cells seems to be transferred through numerous zones of neuropile to large unipolar neurons of the ganglion cortical layer. 相似文献
62.
单光纤光栅实现位移、温度同时区分测量 总被引:10,自引:1,他引:9
结合光纤光栅悬臂梁调谐的特点,采用悬臂梁矩形梁结构,将光纤光栅粘贴在悬臂梁侧面,利用反射波的带宽对应变敏感而对温度不敏感的特性解调悬臂梁自由端的垂直位移,和反射波的中心波长对温度敏感而对应变不敏感的特性解调温度,成功地实现了对位移和温度的同时测量.基于光谱分析仪0.1 nm的光谱分辨率,实验可得到位移、温度同时区分测量系统的带宽随位移变化的灵敏度为0.153 nm/mm,位移分辨率为0.193 mm,位移测量范围可达6.15 mm;中心波长随温度变化的灵敏度为0.029 nm/℃,温度分辨率为3.4℃,温度测量范围为45℃.实验结果与理论分析基本一致. 相似文献
63.
IB Krasnov EI Alekseev VI Loginov TE Burkovskaia NA Chel'naia 《Canadian Metallurgical Quarterly》1998,32(5):31-40
To elicit the mechanism of facilitating the mammals' adaptation to repeated changed gravity influence, the pituitary, thyroid, blood and bone marrow were investigated morphologically in rats exposed to single and repeated hypergravity (2 g) and Coriolis accelerations for 5 days during rotation on centrifuge. No distinct difference in blood and bone marrow cytology was determined after single and repeated exposure to 2 g and the Coriolis accelerations. Compared to single and in contrast to single and repeated exposures to the Coriolis accelerations, a repeated 2 g influence produced some structural changes in somatotropic cells of the pituitary and thyroid parenchyma of the thyroid. These changes were indicative of a significant intensification of synthesis and secretion of somatotropic and thyroid hormones. Elevated functional activity of the somatotropic cells and thyroid parenchyma during repeated exposure to 2 g appears to be a part of mechanism that makes adaptation to repeated hypergravity easier and points to the ability of mammals "to remember" changed gravity. It also advocates for the potentiality of intermittent centrifugation as a means of generating artificial gravity forces in space flight. 相似文献
64.
Ezzat A EI‐Katatny Samih A Halawy Mohamed A Mohamed Mohamed I Zaki 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2000,75(5):394-402
Aluminium dross tailings (ADT), a chemical waste from a factory producing aluminium in Egypt, was used for the recovery of the aluminium content in the form of alumina (Al2O3). Extraction of the aluminium was carried out via atmospheric‐ and high‐pressure leaching with caustic soda. Then, it was separated from the sodium aluminate solutions thus obtained, using six different precipitation methods. The precipitates were filtered, washed, dried and calcined at 600 °C to produce the test aluminas. The precipitates and the calcination products were analysed for their chemical and crystalline phase compositions. The calcination products (aluminas) were subjected to sorpometry for surface area determination, and to particle sizing. The results indicated that highly pure (SiO2 < 0.53% and Na2O < 0.14%), well‐defined crystalline γ‐aluminas of high surface areas (>200 m2 g−1) and uniform small crystallite sizes (60–70 Å) could be efficiently recovered from ADT. Optimal recovery conditions were examined and determined. © 2000 Society of Chemical Industry 相似文献
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SV Skurkovich AS Skorikova NA Dubrovina TV Riabova EI Eremkina VN Golodnenkova EG Klinova AJ Olshanski NF Shurlapova 《Canadian Metallurgical Quarterly》1977,39(5):344-350
A research study and discussion of antiinterferon immunoglobulin in the treatment of rheumatoid arthritis and systemic lupus erythematosus, and its possible value in the treatment of allergic diseases, autoimmune diseases and other diseases where it is presumed there may be an autoimmune genesis. 相似文献
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组合圆锥-圆柱形壳形式的钢贮罐是一种常见的用于储存液体的压力罐。大部分此类压力罐的破坏都由于钢壳的失稳而引起。引起这些破坏的主要原因是没有适当的设计方法来对这类结构进行设计。在本次研究中,提出了简化的设计方法,以保证静水加载的组合钢罐在发生屈曲时的安全。应用非线性有限元模型进行数值模拟,对大变形和几何缺陷对钢罐稳定性的破坏作用进行分析。采用有限元计算结果与非线性回归分析建立函数,将壳的总应力与膜应力关联起来。采用算例说明了所提议设计方法的应用。 相似文献
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