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991.
992.
X.M. Long X.S. Miao J.J. Sun X.M. Cheng H. Tong Y. Li D.H. Yang J.D. Huang C. Liu 《Solid-state electronics》2012,67(1):1-5
In this paper, the volume-minimized model of phase change memory (PCM) cell with Ge2Sb2Te5 (GST) material has been established to study the dynamic switching (set-to-reset) characteristic dependence on the sidewall angle. Joule heating volume, threshold current, dynamic resistance and phase transition rate of PCM cells by current pulse are all calculated. The results show that the threshold current increases with decreasing the sidewall angle and is significantly impacted by the feature size and aspect ratio. The PCM cell of 90° sidewall angle exhibits the smallest Joule heating volume, the highest RESET resistance and the fastest phase transition property. 相似文献
993.
994.
995.
Yong Xu Liying Wang Yujia Tong Sheng Xiang Xinyu Guo Jing Li Haixiang Gao Xuemin Wu 《应用聚合物科学杂志》2016,133(35)
Polyurethane, a controlled release material, has been widely applied in many fields due to its high thermal and mechanical stability, corrosion resistance, and low cost. In this article, we prepared carbosulfan/polyurethane microcapsules by an interfacial polymerization method using modified isocyanate as the precursor and triethanolamine as a curing agent. The microcapsules were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis, and their release kinetics, chemical stability, and the safety of wheat seeds coating were also detected. The microcapsules had an excellent encapsulation efficiency and loading ability for carbosulfan ∼96.23% and 50%, respectively. Furthermore, the microcapsules improved the chemical stability of the carbosulfan and exhibited an excellent sustained release property (above 30 days), which controlled the carbosulfan and carbofuran at an appropriate level for reducing the adverse effects on the environment and agricultural products. The coated wheat seeds germination rate test showed that compared with the emulsifiable concentrate, the microcapsules almost had no effect on the germination rate, plant height, and root length. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43844. 相似文献
996.
山东省精神卫生中心病房教研综合楼建设特色 总被引:1,自引:0,他引:1
针对山东省精神卫生中心病房教研综合楼建设特色进行了分析,分别阐述了该病房教研综合楼的安全特色,人文特色,科学特色,对今后同类精神卫生工程项目设计具有一定指导意义。 相似文献
997.
目前,我国正处于城镇化建设的关键时期。党的十八大提出,要坚持走中国特色新型城镇化道路。本文以生态建筑在成都的发展为例,对将生态建筑设计如何促进新型城镇化的发展提出了个人的粗浅建议。 相似文献
998.
宾夕法尼亚大学设计学院成立于19世纪末,许多著名的建筑师、理论家毕业于此,包括路易斯·康。20世纪初至少有15位中国留学生选择宾大建筑系进行深造,包括陈植、杨廷宝、梁思成、林徽因等。宾大教学过程中非常重视理论研究、实践探讨和艺术表达之间的关系。教师非常强调把这些多种学习结合在一起,注重对于问题的新思考模式研究。该文介绍了宾西法尼亚大学设计学院的历史沿革、教学情况、课程设置,探讨了设计学院的教学思想和课程设置特点,希望能为国内建筑教育提供一定的思考。 相似文献
999.
Tong Zhang Qing‐Mei Yan Lin Ye 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2010,85(10):1340-1345
BACKGROUND: This study was conducted to investigate the feasibility and performance of nitrogen removal through the complete autotrophic nitrogen removal over nitrite (CANON) process for saline wastewater in a continuous reactor, and to characterize microorganisms in the sludge from the reactor using DNA‐based techniques. RESULTS: The nitrogen removal experiment in the reactor was operated over five phases for 286 days treating a synthetic sewage of 1.2% salinity at 21–25 °C. At dissolved oxygen (DO) concentrations of 0.5–1.0 mg L?1 and in the presence of glucose, NO2? was accumulated, indicating the activity of ammonia‐oxidizing bacteria (AOB). At DO concentration of 0.5 mg L?1 without organic substrate, the anaerobic ammonium oxidation (Anammox) process was the major pathway responsible for nitrogen removal, with a total nitrogen removal of 70% and an ammonium conversion efficiency of 96%. A maximum ammonium removal rate of 0.57 kg‐N m?3 d?1 was achieved during the experimental period. The concentrations of AOB and Anammox bacteria were monitored over the operation of reactor using quantitative real‐time polymerase chain reaction (qRT‐PCR). CONCLUSION: In this study, autotrophic nitrogen removal process was achieved under salinity condition in a one‐reactor system. An over 100 fold increase of AOB was found due to the increased supply of ammonium at the beginning, then AOB concentration decreased temporarily in correspondence with the decreased DO, and the AOB resumed their concentration at the last phase. The Anammox bacteria abundance was about 150 fold higher than that at the beginning, indicating the successful enrichment of Anammox bacteria in the reactor. Copyright © 2010 Society of Chemical Industry 相似文献
1000.
Vehicle mass is an important parameter in vehicle dynamics control systems. Although many algorithms have been developed for the estimation of mass, none of them have yet taken into account the different types of resistance that occur under different conditions. This paper proposes a vehicle mass estimator. The estimator incorporates road gradient information in the longitudinal accelerometer signal, and it removes the road grade from the longitudinal dynamics of the vehicle. Then, two different recursive least square method (RLSM) schemes are proposed to estimate the driving resistance and the mass independently based on the acceleration partition under different conditions. A 6 DOF dynamic model of four In-wheel Motor Vehicle is built to assist in the design of the algorithm and in the setting of the parameters. The acceleration limits are determined to not only reduce the estimated error but also ensure enough data for the resistance estimation and mass estimation in some critical situations. The modification of the algorithm is also discussed to improve the result of the mass estimation. Experiment data on asphalt road, plastic runway, and gravel road and on sloping roads are used to validate the estimation algorithm. The adaptability of the algorithm is improved by using data collected under several critical operating conditions. The experimental results show the error of the estimation process to be within 2.6%, which indicates that the algorithm can estimate mass with great accuracy regardless of the road surface and gradient changes and that it may be valuable in engineering applications. This paper proposes a recursive least square vehicle mass estimation method based on acceleration partition. 相似文献