High-Precision Synchronous Test Method of Vibration Performance Parameters for Fused Quartz Hemispherical Resonator

Measurement ◽  
2021 ◽  
pp. 109924
Author(s):  
Zhennan Wei ◽  
Guoxing Yi ◽  
Yan Huo ◽  
Boqi Xi ◽  
Yu Zhao
2011 ◽  
Vol 383-390 ◽  
pp. 4486-4491
Author(s):  
Zhong Quan Luan ◽  
Hu Yan Ji ◽  
Qing Dong Yang

Linear Motors have been used more and more widely in high precision and high-speed linear motion for CNC machine tools, but uniform testing standards and methods for linear motor performance have not been established in China. Based on the virtual instrument software platform by means of computer technology, research and development of the test platform for synthetic performance parameters of linear motors can realize the rapid and accurate measurement, automatic storage and processing of linear-motor output, currents, positions, temperatures and other performance parameters. , Meanwhile, the platform can also provide the technical direction for design or improvement of linear motors, and technically support the formulation of related standards. Experiments showed that the test platform for synthetic performance parameters of linear motors can achieve high precision and automatic measurement to meet the testing requirements for synthetic performance of linear motors.


Author(s):  
Geng-feng Zheng ◽  
Shun-feng Ma ◽  
Ji-gang Sun ◽  
Long-xu Jin ◽  
Ke Zhang

Author(s):  
Suwari ◽  
Sherlly M.F. Ledoh ◽  
Philiphi de Rozari

ABSTRACT Validation of analytical methods is the process of proving that the methods used are scientifically good and suitable for certain purposes. The aim of this study was to validate the analytical method of lead in fish meal matrix by electrothermal atomic absorption spectroscopy (ETAAS) using a phosphate modifier. The research begins with optimization of the analytical conditions that include pyrolysis (ashing) and atomizing temperature, and continues with the validation process by evaluating the analytical performance parameters using a certified reference material (CRM). Method validation was carried out by determining the level of accuracy and precision as well as lead content in a CRM Cod Muscle-422 from BCR. Each experiment was conducted at a wavelength of 283.3 nm, a lamp current of 9.0 amperes, a slit width of 1.3 nm and an argon carrier gas. The optimal pyrolysis and atomizing temperature of lead obtained by adding phosphate modifier was 650 oC and 2000 oC, respectively. The results obtained in this study indicate that the ETAAS lead analysis method using a phosphate modifier is feasible as a test method with an RSD of 3.79%, precision of 0.0043, relative error of 4.0%, accuracy of 104% and recovery of 98% ± 3%. The results of the validation method obtained that the 95% confidence interval for Pb content was 0.088 ± 0.023 µg/g, still within the range of Pb levels in the certificate, namely 0.085 ± 0.015 µg/g of Pb. Keywords: Validation, CRM, Cod Muscle, ETAAS, Lead


2013 ◽  
Vol 373-375 ◽  
pp. 358-362
Author(s):  
Zhan Wei Xu ◽  
Gui Lin Zheng

A high-precision pH sensor based on electrochemical principle is proposed in the paper. The principle of the sensor, the performance parameters of MCU, hardware architecture and experiment are introduced. The NEC microprocessor, which is low-power and high stability, is adopted as core processor. The three operational amplifiers same-phase parallel amplifying circuit not only matches the impendence of the pH combination electrode, but also eliminates the impact of wire resistance on pH measurement. The system's capacity of resisting disturbance is improved. Using 18-bit AD converter, which has programmable amplifier on chip, improves measurement accuracy. Both theoretical analysis and experimental results show the effectiveness of the pH sensor. A full description of the pH sensor and implementation are presented.


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