Measurement of molecular orientation using longitudinal ultrasound and its first application in in-situ characterization

In this study, a method for measuring the degree of molecular orientation with longitudinal ultrasonic waves is proposed. Based on the ultrasonic-wave equation and linear superposition principle, the relationship between the ultrasound velocity and degree of orientation was established. Online and offline experiments were performed to validate the proposed method by measuring the degrees of orientation with dichromic Fourier transform infrared spectroscopy and two-dimensional wide-angle X-ray diffraction. The experimental results show a negative correlation between the ultrasound velocity and degree of orientation, which agrees well with our mathematical model. Furthermore, the mechanism of the orientation measurement through the ultrasound velocity and the deviations of the proposed method were analyzed. The combined uncertainties of orientation in the offline measurement were found within the range of ±0.30 - 2.54%. In general, the proposed method is safe, non-destructive and valid for the in-situ characterization of molecular orientation.
Source: Polymer - Category: Chemistry Source Type: research

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Publication date: Available online 25 January 2020Source: Clinics and Research in Hepatology and GastroenterologyAuthor(s): Wen-Yi Liu, Jian-Hong Wang, Yuan Guo, Xin Wang, Xiao-Dong Wu, Chuan-Shen Xu, Yang Zhao, Yun-Jin ZangSummaryBackgroundAn objective and accurate evaluation of liver grafts is required to improve the prognosis of liver transplant recipients and to increase the number of available liver grafts.AimTo compare outcomes using FibroScan with that of pathology in liver grafts from brain-dead donors (DBD).MethodsLiver grafts from 52 DBD were examined using ultrasound (US), FibroScan before liver transplantation ...
Source: Clinics and Research in Hepatology and Gastroenterology - Category: Gastroenterology Source Type: research
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Source: Brazilian Journal of Otorhinolaryngology - Category: ENT & OMF Source Type: research
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Source: International Journal of Radiation Biology - Category: Radiology Tags: Int J Radiat Biol Source Type: research
Authors: Tagliaferri S, Esposito FG, Esposito G, Saccone G, Signorini MG, Magenes G, Campanile M, Guida M, Zullo F Abstract Analysing antepartum and intrapartum computerised cardiotocographic (cCTG) parameters in physiological term pregnancies with nuchal (NC) or body cord (BC), in order to correlate them with labour events and neonatal outcome. We enrolled 808 pregnant women, composed of 264 with 'one NC', 121 with 'multiple NCs', 39 with BC and 384 with 'no NC', were monitored from the 37th week of gestation before labour, while 49 pregnant women with 'one or more NCs' and 47 with 'no NCs' were analysed during la...
Source: Journal of Obstetrics and Gynaecology - Category: OBGYN Tags: J Obstet Gynaecol Source Type: research
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Source: Sensors and Actuators B: Chemical - Category: Chemistry Source Type: research
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Source: MICCAI International Conference on Medical Image Computing and Computer-Assisted Intervention - Category: Radiology Tags: Med Image Comput Comput Assist Interv Source Type: research
Source: Journal of Maternal-Fetal and Neonatal Medicine - Category: Perinatology & Neonatology Authors: Source Type: research
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Source: Biomedical Signal Processing and Control - Category: Biomedical Science Source Type: research
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Source: Inorganic Chemistry Communications - Category: Chemistry Source Type: research
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