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131.
We present chaos synchronization between two new different chaotic systems by using active control. The proposed controller ensures that the states of the controlled chaotic response system asymptotically synchronizes the states of the drive system. Numerical simulations are shown to verify the result. 相似文献
132.
Effect of Alumina and Chromium Interlayers on Microstructures and Optical Properties of Thin Ag Films on Glass Substrates 下载免费PDF全文
Effects of alumina and chromium interlayers on the microstructure and optical properties of thin Ag films are investigated by using spectrophotometry, x-ray diffraction and AFM. The characteristics of Ag films in Ag/glass, Ag/l2O3/glass and Ag/Cr/glass stacks are analysed. The results indicate that the insertion of an Al2O3 or Cr layer decreases the grains and influences the reflectance of Ag films. The reflectance of the Ag film can be increased by controlling the thickness of alumina interlayer. The stability of Ag films is improved and the adhesion of Ag films on glass substrates is enhanced by alumina as an interlayer. 相似文献
133.
Molecular dynamics simulations are performed to investigate the behaviour of helium atoms in titanium at a temperature of 30OK. The nucleation and growth of helium bubble has been simulated up to 50 helium atoms. The approach to simulate the bubble growth is to add helium atoms one by one to the bubble and let the system evolve. The titanium cohesion is based on the tight binding scheme derived from the embedded atom method, and the helium-titanium interaction is characterized by fitted potential in the form of a Lennard-Jones function. The pressure in small helium bubbles is approximately calculated. The simulation results show that the pressure will decrease with the increasing bubble size, while increase with the increasing helium atoms. An analytic function about the quantitative relationship of the pressure with the bubble size and number of helium atoms is also fitted. 相似文献
134.
In this paper, the collective motion of self-driven robots is studied experimentally and theoretically. In the channel,the flowrate of robots increases with the density linearly, even if the density of the robots tends to 1.0. There is no abrupt drop in the flowrate, similar to the collective motion of ants. We find that the robots will adjust their velocities by a serial of tiny collisions. The speed-adjustment will affect both robots involved in the collision, and will help to maintain a nearly uniform velocity for the robots. As a result, the flowrate drop will disappear. In the motion, the robots neither gather together nor scatter completely. Instead, they form some clusters to move together. These clusters are not stable during the moving process, but their sizes follow a power-law-alike distribution. We propose a theoretical model to simulate this collective motion process, which can reproduce these behaviors well. Analytic results about the flowrate behavior are also consistent with experiments. 相似文献
135.
Using the diluted S1813 UV photoresist as a sacrificial layer, we successfully fabricate a superconducting suspended parallel-plate capacitor, in which the top layer of aluminum film acts as a membrane mechanical resonator. Together with a superconducting octagonal spiral inductor, this parallel-plate capacitor constitutes a superconducting microwave resonator. At m K temperature, the transmission characteristic and spectrum of the microwave resonator are measured.Sideband frequencies caused by the vibration of the membrane mechanical resonator are clearly demonstrated. By downconverting with a mixer, the dependence of fundamental frequency and its harmonics on the input microwave power are clearly demonstrated, which is consistent with the numerical simulation. 相似文献
137.
本文以二硫代二苯甲酸、均苯四甲酸酐和没食子酸为修饰剂,通过后交联反应和化学修饰反应制备了3种酸性功能基修饰的超高交联树脂。通过等温吸附实验和吸附动力学实验,探讨了3种酸性吸附树脂对2,6-二氯苯酚(2,6-DCP)的吸附性能和吸附机制。结果表明,3种酸性吸附树脂对2,6-DCP均具有良好的吸附性能,吸附量随着2,6-DCP初始浓度的增大而增加,随着温度的升高而减小。Langmuir和Freundlich等温吸附方程均能够较好地拟合吸附等温线,3种酸性树脂对2,6-DCP的吸附机理较复杂。吸附热力学结果表明,吸附过程主要为放热、自发的物理吸附过程。3种酸性树脂对2,6-DCP的吸附动力学过程符合准一级动力学方程,颗粒内扩散是该吸附过程的主要控制步骤。3种酸性吸附树脂对2,6-DCP的吸附速率常数大小顺序为kGAMRkDSTAMRkPMDAMR。 相似文献
138.
内部孔隙影响着药片的崩解特性,进而影响药效的发挥,但目前鲜有关于药片孔隙率有效检测手段的报道。基于太赫兹脉冲的飞行时间测量原理,利用太赫兹时域光谱技术研究了微晶纤维素和吲哚美辛混合片剂的孔隙率与折射率、吲哚美辛质量分数之间的定量关系;建立了三者关系的数学计算模型,通过实际测试固体样品片剂的太赫兹时域光谱,计算了片剂的孔隙率、折射率。结果表明:片剂的孔隙率与折射率、不同成分质量分数间存在线性关系,与建立的数学计算模型相符。利用太赫兹光谱法测得的孔隙率与采用气体置换法测量的孔隙率的平均相对误差为6.0%,与采用密度法计算的孔隙率的平均相对误差为8.9%,表明利用太赫兹光谱法测量片剂孔隙率具有可行性,能够成为药物片剂质量监测的补充手段。 相似文献
139.
两种非晶碳化硅薄膜发光二极管 总被引:1,自引:0,他引:1
利用硅烷与甲烷的混合气在射频电场下的等离子体反应,淀积不同导电类型的非晶碳化硅薄膜,制成了p-i-n结注入型和均匀材料的碰撞电离型两种大面积发光二极管。本文报导这两种非晶发光器件的结构设计及光谱特性,并对器件的发光机现进行了讨论。 相似文献
140.
本文给出利用光泵磁共振曲线测量氢原子密度的实验.在我们的实验中,当射频源放电功率一定时,在25~61℃的泡温范围内测量到9.2×1011~1.6×1011(原子/厘米3)的氢原子密度.实验结果表明,当放电功率一定时,氢原子密度随泡温升高而下降. 相似文献