超声协同光催化处理焦化废水研究

利用纳米TiO2进行超声协同光催化处理焦化废水实验,探讨了其协同作用机理,考察了TiO2加入量、超声功率、pH值对CODCr和NH4+-N去除效果的影响。分析了曝气、H2O2或Fenton试剂与超声和光催化的协同作用机理,研究了对CODCr和NH4+-N去除效果的影响。结果表明利用超声协同光催化处理焦化废水,CODCr和NH4+-N的去除率显著提高,许多难生物降解有机物被降解去除。     

硫酸盐腐蚀粉煤灰混凝土后强度超声检测评定

为进一步研究混凝土受硫酸盐侵蚀的机理,以粉煤灰混凝土为研究对象,在高浓度硫酸盐溶液中进行加速腐蚀,并结合受硫酸盐腐蚀后混凝土强度变化规律,采用超声平测法对受腐蚀混凝土进行检测．研究结果表明,超声平测声速与损伤度之间有较好的回归关系．在此基础上,建立了腐蚀混凝土强度与声速之间的关系模型．     

高频超声降解对硫磷的反应动力学及机理

研究了高频超声降解水溶液中对硫磷的反应动力学以及机理.引入拟一级反应动力学模型以及响应面方法对对硫磷初始浓度、超声功率以及频率对对硫磷降解效果的影响进行评估.经过响应面实验设计和实验以及对拟合的二次模型分析发现,拟合模型显著(P=0.000 2),且拟合不足不显著(P=0.113 6),相关系数平方R2=0.973 3,表明模型具有较好的回归性.对于对硫磷降解拟一级动力学表观速率系数具有显著性影响的一次项为超声功率值以及对硫磷的初始浓度值,二次项为超声频率值,交互项均不显著.在实验研究的超声功率、频率以及对硫磷初始浓度范围内,对硫磷降解拟一级动力学表观速率系数随超声功率的增大而减小,随初始浓度的增大而减小,并且存在一个最优的降解频率.     

溶液性质对超声波解吸SO2的影响

研究了在超声波作用下柠檬酸钠溶液的性质对SO2解吸率的影响,探讨了超声场下柠檬酸盐溶液中SO2的解吸机理.结果表明:(1)在柠檬酸钠浓度较低,或者柠檬酸钠溶液初始pH值较低的条件下均能产生较好的解吸效果;(2)少量惰性气体的通入或者表面活性剂的加入能够降低溶液黏度,产生空化效应,从而提高了SO2的解吸率;(3)通过对比实验证明解吸结果与理论分析相吻合,其研究结果为SO2的深度解吸提供了技术思路,也为该项技术的工业放大提供了一定的基础数据.     

关于医用超声波雾化器性能改进的探讨

阐述的主要内容有以下4个,介绍了超声波雾化器的应用范围,指出了用超声波雾化器治疗疾病特点,本文还乐观地估计了超声波雾化器的应用前景;介绍了超声波雾化器的基础电路,并对其工作原理进行了简要的分析;指出了一些超声波雾化器产品的某些不足之处,并提出了相应的改进措施;指出了提高超声波雾化器的雾化量的必要性,并就提高大功率超声波雾化器工作稳定性的技术问题进行分析与探讨.     

超声波对黑曲霉细胞破壁作用的研究

用均匀设计法考察了超声时间、超声温度和超声功率对黑曲霉细胞破壁效果的影响．实验结果表明最优条件为：超声时间50min,超声温度60℃,超声功率200W,超声法与高压均质法比较,超声法破壁效果较好。     

Ultrasonic power features of wire bonding and thermosonic flip chip bonding in microelectronics packaging

The driving voltage and current signals of piezoeeramie transducer (PZT) were measured directly by designing circuits from ultrasonic generator and using a data acquisition software system. The input impedance and power of PZT were investigated by using root mean square (RMS) calculation. The vibration driven by high frequency was tested by laser Doppler vibrometer (PSV-400-M2). And the thermosonic bonding features were observed by scanning electron microscope (JSM-6360LV). The results show that the input power of bonding is lower than that of no load. The input impedance of bonding is greater than that of no load.Nonlinear phase, plastic flow and expansion period, and strengthening bonding process are shown in the impedance and power curves. The ultrasonic power is in direct proportion to the vibration displacement driven by the power, and greater displacements driven by high power (5W) result in welding failure phenomena, such as crack, break, and peeling off in wedge bonding. For thermosonic flip chip bonding, the high power decreases position precision of bonding or results in slippage and rotation phenomena of bumps. To improve reliability and precision of thermosonic bonding, the low ultrasonic power (about 1-5W) should be chosen.     

Fast recognition algorithm of underwater micro-terrain based on ultrasonic detection

An algorithm was proposed to fast recognize three types of underwater micro-terrain, i.e. the level, the gradient and the uneven. With pendulum single beam bathymeter, the hard level concrete floor, the random uneven floor and the gradient wood panel （8°） were ultrasonically detected 20 times, respectively. The results show that the algorithm is right from fact that the first clustering values of the uneven are all less than the threshold value of 60.0% that is obtained by the level and gradient samples. The algorithm based on the dynamic clustering theory can effectively eliminate the influences of the exceptional elevation values produced by the disturbances resulted from the grazing angle; the characteristic of bottom material and environmental noises, and its real-time capability is good. Thus, the algorithm provides a foundation for the next restructuring of the micro-terrain.     

A novel traveling wave ultrasonic motor using a bar shaped transducer

A novel traveling wave ultrasonic motor was proposed. The structure of the motor is rather simple and different from the conventional traveling wave ultrasonic motors. Its production processes are very convenient. It is composed of a stator constituted with a ring and a bar shaped transducer and two cone shaped rotors. The rotors were pressed on inner surface of the ring by means of a pre-pressure system. The bar shaped transducer has a sand- wich-like configuration,where two sets of piezoelectric element are bolted. One set excites a longitudinal vibration of the bar, and the other set excites a flexural vibration of the bar. The ring＇s traveling wave excited with the longitudinal vibration and the bending vibration of the bar transducer was simulated with FEM （finite element method）. The prototype of the motor was made and investigated experimentally for its performance. Its maximum torque and rotating speed are 0.25 N · m and 50 r/min, respectively.     

Fuzzy Logic Supervised Teleoperation Control for Mobile Robot

The supervised teleoperation control is presented for a mobile robot to implement the tasks by using fuzzy logic. The teleoperation control system includes joystick based user interaction mechanism,the high level instruction set and fuzzy logic behaviors integrated in a supervised autonomy teleoperation control system for indoor navigation. These behaviors include left wall following,right wall following,turn left,turn right,left obstacle avoidance,right obstacle avoidance and corridor following based on ultrasonic range finders data. The robot compares the instructive high level command from the operator and relays back a suggestive signal back to the operator in case of mismatch between environment and instructive command. This strategy relieves the operator's cognitive burden,handle unforeseen situations and uncertainties of environment autonomously. The effectiveness of the proposed method for navigation in an unstructured environment is verified by experiments conducted on a mobile robot equipped with only ultrasonic range finders for environment sensing.