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speeds of sound and Excess Isentropic Compressibilities of Butyl Acetate＋Aromatic Hydrocarbons

Chinese Journal of Chemical Engineering 2008年第4期16卷 599-604页

作者： Bal Raj Deshwal Anu Sharma Krishan Chander Singh Department of Chemistry All India Jat Heroes Memorial College Rohtak-124001 India Department of Chemistry Maharshi Dayanand University Rohtak-124001 India

speed of sound data for butyl acetate＋benzene, or toluene, or o-xylene, or m-xylene, or p-xylene binary mixtures have been measured over the entire range of mole fraction at 308.15 K. The excess isentropic compressibilities （ Ks^E ） were computed from speed of sound and density data, derived from molar excess volume data. The Ks^E values were analyzed by using graph theoretical approach. The Ks^E values evaluated by graph theory compared reasonably well with their corresponding experimental values. The Ks^E data were also expressed in terms of Redlich-Kister polynomial equation to derive the coefficients and the standard deviation.

关键词： speed of sound isentropic compressibilities graph theory butyl acetate aromatic hydrocarbon

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Temperature imaging with speed of ultrasonic transmission tomography for medical treatment control:A physical model-based method

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Chinese Physics B 2015年第10期24卷 297-302页

作者：储哲琦袁杰 Stephen Z.Pinter Oliver D.Kripfgans 王学鼎 Paul L.Carson 刘晓峻 School of Electronic Science and Engineering Nanjing University Department of Radiology University of Michigan School of Physics Nanjing University

Hyperthermia is a promising method to enhance chemo and radiation therapy of breast cancer. In the process of hyperthermia, temperature monitoring is of great importance to assure the effectiveness of treatment. The transmission speed of ultrasound in biomedical tissue changes with temperature. However, when mapping the speed of sound directly to temperature in each pixel as desired for using all speeds of ultrasound data, temperature bipolar edge enhancement artifacts occur near the boundary of two tissues with different speeds of ultrasound. After the analysis of the reasons for causing these artifacts, an optimized method is introduced to rebuild the temperature field image by using the continuity constraint as the judgment criterion. The significant smoothness of the rebuilding image in the transitional area shows that our proposed method can build a more precise temperature image for controlling the medical thermal treatment.

关键词： temperature imaging speed of sound continuous constrain thermal therapy

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Novel Image Optimization Method for Joint Photoacoustic Tomography

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Chinese Physics Letters 2014年第5期31卷 84-88页

作者：李文超袁杰沈庆宏于耀周余都思丹刘晓峻徐冠王学鼎 School of Electronic Science and Engineering Nanjing University Nanjing 210093 School of Physics Nanjing University Nanjing 210093 Department of Radiology University of Michigan Ann Arbor MI 48109 USA

The distribution of speed of sound （SOS） in biomedical tissue and delay compensation （DC） have significant impact on the image quality of photoacoustic tomography （PAT）. When imaging human peripheral joints, using fixed SOS and DC can only ensure that the reconstructed images are focused in a limited depth range, whereas they are defoeused at other depths, which cause severe artifacts and blurring. In this work, a linear-DC based reconstruction approach is proposed to focus the whole PAT image region. It is proved by two in vivo experiments that, compared with traditional delay-and-sum back projection algorithms, the proposed method can effectively optimize the image quality of articular tissues in PAT.

关键词： speed of sound PHOTOACOUSTIC effect IMAGE quality analysis sound pressure TIME-of-flight spectrometry

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Combating acoustic heterogeneity in photoacoustic computed tomography:A review

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Journal of Innovative Optical Health Sciences 2020年第3期3卷 32-47页

作者： Tong Wang Wen Liu Chao Tian Department of Optics and Optical Engineering University of Science and Technology of China Hefei Anhui 230026 P.R.China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of China Hefei Anhui 230026P.R.China Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of China Hefei Anhui 230026P.R.China

Based on the energy conversion of light into sound,photoacoustic computed tomography(PACT)is an emerging biomedical imaging modality and has unique applications in a range of biomedical *** PACT,image formation relies on a process called acoustic inversion from received photoacoustic *** most PACT systems perform this inversion with a basic assumption that biological tissues are acoustically homogeneous,the community gradually rea-lizes that the intrinsic acoustic heterogeneity of tissues could pose distortions and artifacts to finally formed *** paper surveys the most recent research progress on acoustic het-erogeneity correction in *** major strategies are reviewed in detail,including half-time or partial-time reconstruction,autofocus reconstruction by optimizing sound speed maps,joint reconstruction of optical absorption and sound speed maps,and ultrasound computed tomog-raphy(USCT)enhanced *** correction of acoustic heterogeneity helps improve the imaging performance of PACT.

关键词： Photoacoustic computed tomography image reconstruction acoustic heterogeneity ultrasound computed tomography speed of sound

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Unleashing the Power of Information Theory: Enhancing Accuracy in Modeling Physical Phenomena

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Journal of Applied Mathematics and Physics 2023年第3期11卷 760-779页

作者： Boris Menin Mechanical & Refrigeration Expert Beer-Sheva Israel

When building a model of a physical phenomenon or process, scientists face an inevitable compromise between the simplicity of the model (qualitative-quantitative set of variables) and its accuracy. For hundreds of years, the visual simplicity of a law testified to the genius and depth of the physical thinking of the scientist who proposed it. Currently, the desire for a deeper physical understanding of the surrounding world and newly discovered physical phenomena motivates researchers to increase the number of variables considered in a model. This direction leads to an increased probability of choosing an inaccurate or even erroneous model. This study describes a method for estimating the limit of measurement accuracy, taking into account the stage of model building in terms of storage, transmission, processing and use of information by the observer. This limit, due to the finite amount of information stored in the model, allows you to select the optimal number of variables for the best reproduction of the observed object and calculate the exact values of the threshold discrepancy between the model and the phenomenon under study in measurement theory. We consider two examples: measurement of the speed of sound and measurement of physical constants.

关键词： Finite Information Quantity International System of Units Modelling Physical Constant speed of sound

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