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81.
TC21钛合金是新型的高强韧损伤容限型钛合金,其模锻件为网篮组织,锻后热处理工艺采用双重退火工艺。本研究采用金相法、SEM等方法系统研究了TC21钛合金模锻件的锻后热处理工艺和显微组织演变规律。试验分析了TC21钛合金模锻件锻后第1次退火加热温度、第2次退火加热温度和保温时间等工艺参数条件下的初生α相数量、形状以及网篮组织形貌特征的变化规律,为TC21钛合金模锻件获得高强、高韧和损伤容限优良综合性能奠定基础。 相似文献
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高温压力传感器温度漂移补偿研究 总被引:1,自引:0,他引:1
针对高温压力传感器耐高温和高压的测量的要求,设计了压阻式压力传感器硅杯式芯片版图,采用SIMOX(separationbyimplantedoxygen)技术SOI(silicononinsulator)晶片,在微加工平台上制作了该芯片,获得了差动等臂等应变的惠斯登检测电桥。对采用耐高温封装后的传感器的热零点漂移、热灵敏度漂移和零位输出的补偿作了研究,设计了补偿电路,推导了热灵敏度漂移补偿的计算公式,在通用型高温压力传感器的研发中证明其可行性和实用性,并总结出了经验公式。 相似文献
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用美国模拟器件公司生产的内部集成温度传感器的AD7417转换器和Honsywell公司生产的IH3605热固聚酯电容式RH湿度传感器制成采样板,用AT89C2051控制8点(最多16点)温湿度采样,用TC1602A字符型液晶显示器显示组成数字式温湿度监测系统,该系统电路简单、编程容易,温湿度测量范围大,工作稳定可靠,具有一定的实用价值。 相似文献
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庞 《青岛大学学报(工程技术版)》2004,19(3):47-49
针对TC7135并行接口输出,占用较多的I/O口资源,电路连接较复杂的缺点,提出了一种TC7135和PIC单片机的二线式接口,并根据TC7135的BUSY信号的高电平时间与模拟量成正比和PIC单片机外部中断沿可编程的特性,通过编写适当的软件实现了该接口,同时给出了电路图以及接口程序,源程序已调试通过。实践证明,该接口工作稳定,可以应用在一般的单片机系统中。 相似文献
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Yingjie Shen Hyoung Jae Lee Rui Zhou Hangun Kim Gen Chen Young-Chang Cho Kwonseop Kim 《International journal of molecular sciences》2021,22(10)
Prostate cancer (PCa) is the second most leading cause of death in males. Our previous studies have demonstrated that δ-catenin plays an important role in prostate cancer progression. However, the molecular mechanism underlying the regulation of δ-catenin has not been fully explored yet. In the present study, we found that δ-catenin could induce phosphorylation of p21Waf and stabilize p21 in the cytoplasm, thus blocking its nuclear accumulation for the first time. We also found that δ-catenin could regulate the interaction between AKT and p21, leading to phosphorylation of p21 at Thr-145 residue. Finally, EGF was found to be a key factor upstream of AKT/δ-catenin/p21 for promoting proliferation and metastasis in prostate cancer. Our findings provide new insights into molecular controls of EGF and the development of potential therapeutics targeting δ-catenin to control prostate cancer progression. 相似文献
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ICT infrastructure investments in educational institutions have been one of the key priorities of education policy during the last decade. Despite the attention, research on the effectiveness and efficiency of ICT is inconclusive. This is mainly due to small-scale research with weak identification strategies which lack a proper control group. Using the 2011 ‘Trends in International Mathematics and Science Study’ (TIMSS) data, we define by a Mahalanobis matching a control group with similar student, teacher, school and regional characteristics. The results indicate that accounting or not accounting for these characteristics, may considerably alter the estimated impact of ICT. This suggests that a correction for characteristics related to the student population, teaching staff, administrative personnel and school management is warranted in the evaluation of the impact of ICT. 相似文献
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In this study, the porous multiwall carbon nanotube (MWCNT) foams possessing three-dimensional (3D) scaffold structures have been introduced into polydimethylsiloxane (PDMS) for enhancing the overall thermal conductivity (TC). This unique interconnected structure of freeze-dried MWCNT foams can provide thermally conductive pathways leading to higher TC. The TC of 3D MWCNT and PDMS composites can reach 0.82 W/m K, which is about 455% that of pure PDMS, and 300% higher than that of composites prepared from traditional blending process. The obtained polymer composites not only exhibit superior mechanical properties but also dimensional stability. To evaluate the performance of thermal management, the LED modulus incorporated with the 3D MWCNT/PDMS composite as heat sink is also fabricated. The composites display much faster and higher temperature rise than the pristine PDMS matrix, suggestive of its better thermal dissipation. These results imply that the as-developed 3D-MWCNT/PDMS composite can be a good candidate in thermal interface for thermal management of electronic devices. 相似文献