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用硫酸钠添加剂的方法改善低活性粉煤灰,可以提高二灰碎石的早期强度、减少裂缝、缩短施工周期,并保证施工质量。但添加硫酸钠以后二灰碎石强度的成因和机理尚有许多未知因素,需有待于进一步研究。 相似文献
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研制了一种新颖的应用于网络遥操作机器人系统的网络视频流传输系统,该系统基于C/S模型并采用MPEG4视频编码器对图像进行编解码,实现了机器人现场视频的实时采集、编码、传输和播放。此外,对网络遥操作机器人系统的视频、音频和力信息的传输同步问题展开了研究。实验证明所研制的系统不仅能保证机器人现场图像传输的实时性,而且能较好地实现多信息的同步。 相似文献
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船舶电力系统中交流配电网零线故障的诊断 总被引:1,自引:0,他引:1
戴雅丽 《武汉船舶职业技术学院学报》2009,8(5):31-33
船舶电力系统中采用的三相四线制交流配电网中零线故障时有发生,为了保证船舶电力系统的供电连续性及最大可能地缩短船舶停电时间,本文结合一起零线故障的实际情况,运用电路理论分析了零线故障产生的机理及其危害性,指出三相四线制交流配电网零线接地的重要性,并提出了防止此类事故的基本措施和具体方法。 相似文献
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Objective To evaluate the effect of low-dose insulin [1 U/(kg · d)] in combination with selenium [180 g/(kg · d)] on general physiological parameters and glucose transporter (GLUT4) level in skeletal mnscle of streptozotocin (STZ)-induced diabetic rats. Methods Diabetic rats were treated with insulin, selenium, and insulin and selenium in combination for four weeks. The level of blood glucose was determined using One Tonch SnreStep Blood Glucose meter and the level of GLUT4 in skeletal muscle was examined by immunobiotting and immnnohistochemistry. Results Our data showed that insulin in combination with selenium could significantly lower blood glucose level and restore the disturbance in GLUT4 level in skeletal muscle. Treatment with insulin was only partially effective in restoring diabetic alterations. Conclusion It can be concluded that there is a synergistic action between insulin and selenium, and that treatment of diabetic rats with combined doses of insulin and selenium is effective in the normalization of blood glucose level and correction of altered GLUT4 distribution in skeletal mnscle of diabetic rats. 相似文献
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Objective To construct the prokaryotic expression vector bearing fusion gene NT4-ADNF-9 and lay foundation for further study on genetic therapy of neuraseusory deafness. Methods By means of asymmetrical prince/ template, double stranded eDNA of activity dependent neurotrophic factor-9 (ADNF-9) was obtained, which included restriction enzymes sites on the two extremities. ADNF-9 eDNA was ligated to the signal and leader peptides of nenrotrophin 4 (NT4), and the fusion gene was named NT4-ADNF-9. Then it was suheluned into prokaryotic expression vector pBV220, and called pBV220/ NT4-ADNF-9. Results Evidences of DNA sequence analysis and restrtction enzymes digestion showed that we recombined ADNF-9 eDNA to the 3'terminal of the signal and leader peptides of NT4, and the fusion gene was subcluned into pBV220 successfully. Bioactivity of the products was proved that it could support the cell survival and neurite growth in the primary cultures of dorsal root ganglia (DRG) of embryonic day-8 cbicken neurons as compared to the control. Conclusion Prokaryotic expression vector pBV220/NT4-ADNF-9 can be constructed successfully and the bioactivtty is satisfactory. 相似文献
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