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121.
122.
Jianfeng Wanyan Kun Cao Zhiping Chen Yun Li Chenxi Liu Runqing Wu Xiao-Dong Zhang Rong Chen 《工程(英文)》2021,7(10):1459-1468
The reliable operation of flexible display devices poses a significant engineering challenge regarding the metrology of high barriers against water vapor. No reliable results have been reported in the range of 10–6 g∙(m2∙d)−1, and there is no standard ultra-barrier for calibration. To detect trace amount of water vapor permeation through an ultra-barrier with extremely high sensitivity and a greatly reduced test period, a predictive instrument was developed by integrating permeation models into high-sensitivity mass spectrometry measurement based on dynamic accumulation, detection, and evacuation of the permeant. Detection reliability was ensured by means of calibration using a standard polymer sample. After calibration, the lower detection limit for water vapor permeation is in the range of 10–7 g∙(m2∙d)−1, which satisfies the ultra-barrier requirement. Predictive permeation models were developed and evaluated using experimental data so that the steady-state permeation rate can be forecasted from non-steady-state results, thus enabling effective measurement of ultra-barrier permeation within a significantly shorter test period. 相似文献
123.
Two-dimensional (2D) perovskites are known as one of the most promising luminescent materials due to their structural diversity and outstanding optoelectronic p... 相似文献
124.
天线间耦合度自动测试系统设计 总被引:6,自引:1,他引:5
多天线系统的电磁兼容性很大程度上取决于系统内收发天线间的射频能量耦合。天线间耦合度是评估系统级电磁兼容性的重要指标。针对目前传统手工测试的种种弊端,设计了基于射频开关自动切换的天线间耦合度自动测试系统,详细阐述了系统硬件构成、软件的设计思路以及具体的测试流程,使用LabVIEW编写软件控制收发天线对的自动切换,实现自动测量,具有测量误差小,测量便捷等优点。 相似文献
125.
用故障类型及影响分析法(FMEA),对宁夏石化公司二化肥循环水系统节能改造后的现状进行了调查分析,针对发现的问题提出了改进措施和建议。该分析方法有助于提早发现装置存在隐患,对预防事故发生、减少事故损失有重大意义。 相似文献
126.
Vivanti Giacomo; McCormick Carolyn; Young Gregory S.; Abucayan Floridette; Hatt Naomi; Nadig Aparna; Ozonoff Sally; Rogers Sally J. 《Canadian Metallurgical Quarterly》2011,47(3):841
Typically developing children understand and predict others' behavior by extracting and processing relevant information such as the logic of their actions within the situational constraints and the intentions conveyed by their gaze direction and emotional expressions. Children with autism have difficulties understanding and predicting others' actions. With the use of eye tracking and behavioral measures, we investigated action understanding mechanisms used by 18 children with autism and a well-matched group of 18 typically developing children. Results showed that children with autism (a) consider situational constraints in order to understand the logic of an agent's action and (b) show typical usage of the agent's emotional expressions to infer his or her intentions. We found (c) subtle atypicalities in the way children with autism respond to an agent's direct gaze and (d) marked impairments in their ability to attend to and interpret referential cues such as a head turn for understanding an agent's intentions. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
127.
目的:观察氨氯地平对原发性高血压病人颈动脉内膜中层厚度的影响.方法:选择134例1、2级高血压病人,随机分为两组,A组氨氯地平5-10mg,每日1次;B组吲哒帕胺1.5g,每日1次;治疗12周.如血压不达标可加用ACEI或ARB类药物.结果:治疗2周后两组血压均明显下降,4周后血压趋于达标并稳定,两组的降压幅度无显著差别.12周后与治疗前比较,两组IMT均降低,A组IMT降低更明显,两组比较有显著差异.结论:氨氯地平对逆转原发性高血压病人颈动脉IMT的效果显著. 相似文献
128.
阐述了卧式螺旋离心机污泥脱水的流程及原理,介绍了卧式螺旋离心机在焦化废水处理中的具体应用.通过对影响卧式螺旋离心机运行效果的关键因素加药量、转速、差数等进行优化,污泥含水率由97%下降至70%,取得了良好的效果. 相似文献
129.
重力式纤维束滤池与均粒滤池的对比性平行生产试验表明,纤维束滤池处理效果理想,其滤料使用周期长、截污能力强、滤速高,生产效益显著。同时通过大量实验,对重力式纤维束滤池的除浊结果进行了公式拟合,并通过测试证明其误差0.5%。利用该数学模型可以对除浊结果进行很好的预测与分析。 相似文献
130.
Zhiyue Han Jingchang Zhang Xiuying Yang Hong Zhu Weiliang Cao 《Synthetic Metals》2010,160(19-20):2167-2174
Titanium dioxide and ferric oxide were prepared by the supercritical fluid drying (SCFD) method. A conducting polymer composite, poly(3-octylthiophene)/titanium dioxide/ferric oxide (POT/TiO2/Fe2O3) was first synthesized by chemical method. Transmission electron microscope (TEM) and scanning electron microscope (SEM) depicted the morphology of the samples, defining that TiO2 and Fe2O3 were successfully coated by poly(3-octylthiophene) molecules. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR) showed the chemical interaction between poly(3-octylthiophene) and inorganic compounds in the composite. Cyclic voltammetry (CV) curves showed that the forbidden band gap of the POT/TiO2/Fe2O3 composite is 0.691 eV, realizing the complementary advantages of n and p semiconductor. UV–vis spectra (UV) and fluorescence spectra (PL) showed that its optical performance is far superior to poly(3-octyl thiophene), titanium dioxide and ferric oxide separately. Solar cell was sensitized by POT/TiO2/Fe2O3. A solar-to-electric energy conversion efficiency of 0.499% was attained with the system. 相似文献