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881.
882.
Determination of displacement with a piezoelectric transducer using phase-shift algorithms 总被引:1,自引:0,他引:1
Cheng-Chung Jaing Yi-Lin Shie Chien-Jen Tang Yeuh-Yeong Liou Chun-Ming Chang Chii-Rong Yang 《Optical Review》2009,16(2):170-172
This investigation accurately measures the relationship between applied voltage and the displacement of a piezoelectric transducer
device both by analyzing phase shifting interferometry algorithms and using a Twyman-Green interferometer. Simulations are
performed to calculate unknown phase shifts, especially around π/2 and 3π/2. It is indicated that the Hariharan algorithm is indeed an effective phase shifting interferometry algorithm. 相似文献
883.
Phase-shifting interferometers with three piezoelectric transducers (PZTs) on their phase-shifting adapter (PSA) are widely
used in precision measurement. The guarantee of the PSA to stretch as a flat is very important to the accuracy of the measurement.
In this paper, we propose a systematic self-calibration method to calibrate the different displacements of the PZTs so that
the PSA can be moved evenly as a flat. The proposed method uses only the interference patterns to calibrate the three PZTs
and information about the exact position of the PZTs and the instrument parameters of the interferometer are not required.
Experimental results show that, after calibration by the proposed method, the deviation of the measured phase shift error
could be reduced about 43.1 times from 3.492 to 0.081°. 相似文献
884.
The violet ruthenium complex [(η5-C5Me5)Ru(η5-C3B2Me4R1)] (2a, R1 = Me) reacts with terminal alkynes R2CCH to give yellow 4-borataborepine compounds [(η5-C5Me5)Ru{η7-(MeC)3(R1B)2(R2C2H)}] (4c, R1 = Me, R2 = Ph; 4d, R1 = Me, R2 = SiMe3; 4e, R1 = Me, R2 = H). The insertion of alkynes into the folded C3B2 heterocycle of 2a causes some steric hindrance, which yields with elimination of the distant boranediyl group the corresponding boratabenzene complexes 5 as byproducts. The analogous reactions with internal alkynes R2CCR2 proceed slowly and afford predominantly the boratabenzene complexes [(η5-C5Me5)Ru{η6-(MeC)3(MeB)(R2C)2}] (5f, R2 = Et, 5g, R2 = p-tolyl), respectively. In the latter case, three byproducts are formed: methylboronic acid and 1,2,3,4-tetra-p-tolyl-1,3-butadiene (9) due to hydrolysis of the postulated 2,3,4,5-tetra-p-tolyl-1-methylborole (10) and unexpectedly, the cationic triple-decker complex [{(η5-C5Me5)Ru}2{μ,η7-(MeC)3(MeB)2(CH)2}]Cl (11) having two separated CH groups. The new compounds were characterized by NMR, MS, and single-crystal X-ray studies of 4c, 5f, 9 and 11. 相似文献
885.
Polyaniline (PANI)/glycidyl ether of bisphenol A (SU-8) composite film is elaborated in order to detect ammonia gas. These composite films are characterized by ultraviolet-visible (UV-vis) spectroscopy, Fourier transformed infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The sensitivity to ammonia is measured by optical absorption changes. The ammonia sensing properties of PANI/SU-8 composite films are studied, and then are compared to pure PANI films elaborated by chemical way. Experimental results show that the PANI/SU-8 optical sensor has simultaneously a rapid response to ammonia gas and regenerates easily, that is advantageous compared to pure PANI films. 相似文献
886.
采用固相反应方法在不同烧结升温速率下制备了BaTiO3陶瓷,并对陶瓷样品的晶体结构、表面形貌、介电、压电和铁电性能进行了测试和分析.结果表明:当烧结升温速率为3 ℃/min和5 ℃/min时陶瓷均为四方钙钛矿晶格结构,随升温速率的增大,四方相程度增强,材料平均晶粒尺寸减小,压电系数和铁电性能随之降低,但介电常数随之增大,当烧结升温速率为5 ℃/min介电常数最大,其值为3144.当烧结升温速率为1 ℃/min时陶瓷为正交钙钛矿晶格结构d33和Pr最大,其值为Pr=10 μC/cm2和d33=193 pC/N. 相似文献
887.
The problems of periodic cracks have been widely solved in existing literature of fracture mechanics. Although the assumption of periodicity facilitates the theoretical derivation, practical multiple cracks in most cases are not periodically distributed in materials and structures. The present article performs fracture analysis on a piezoelectric/piezomagnetic/piezoelectric (PE/PM/PE) tri-layered smart structure containing nonperiodic interfacial cracks under magnetic/electric and mechanical loadings. The methods of dislocation simulation, Green's function and Cauchy singular integral equations are employed to solve the problem. Stress intensity factors (SIFs) are numerically calculated, and parametric studies are conducted to demonstrate the variation laws of SIFs versus geometrical parameters. The obtained conclusions may provide references for the optimal design of PE/PM/PE smart structures. 相似文献
888.
物理化学教学内容繁杂且抽象、枯燥乏味,学生容易产生厌学情绪。采用传统教学法往往不能达到较好的教学效果。将Sandwich教学法引入药学专业物理化学的教学实践中,以表面张力的教学为实施例具体阐述了教学设计和实施过程。该教学方法以学生自我学习为主,教师引导为辅,在教学实施的各个环节充分调动学生学习的主动性和积极性,同时培养了学生表达和沟通能力、分析问题和解决问题的能力。 相似文献
889.
Mihály Bessenyei 《Indagationes Mathematicae》2018,29(3):873-877
The aim of this note is to characterize in terms of inequalities those pairs of real functions (acting on a convex subset of a vector space) that possess an affine separator. The main result is originally due to Behrends and Nikodem. Their method is based on the Hahn–Banach Theorem and a variant of the Helly Theorem. In our approach, a direct and independent proof is presented via the Radon and the Helly Theorems. 相似文献
890.
采用了在径向极化情况下横观各向同性的线性本构关系,考虑了材料性质沿径向的梯度分布,对功能梯度压电材料圆环在给定的位移和电势边界条件下,导出了问题的一般解.推导了外壁固定、接地,内壁沿垂向有一微小位移、电势为反对称分布问题的解析解,并计算了该问题在位移和电势作用情况下的位移、电势在不同梯度分布时的数值结果. 相似文献