The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Mariya Lazebnik - One of the best experts on this subject based on the ideXlab platform.
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highly accurate debye models for normal and malignant breast tissue Dielectric Properties at microwave frequencies
IEEE Microwave and Wireless Components Letters, 2007Co-Authors: Mariya Lazebnik, J H Booske, M Okoniewski, Susan C HagnessAbstract:The finite difference time domain (FDTD) method is widely used as a computational tool for development, validation, and optimization of emerging microwave breast cancer detection and treatment techniques. When expressed in terms of Debye parameters, dispersive breast tissue Dielectric Properties can be efficiently incorporated into FDTD codes. Previously, we experimentally characterized the Dielectric Properties of a large number of excised normal and malignant breast tissue samples from 0.5 to 20 GHz. We subdivided the large database of normal tissue data into three groups based on the percent adipose tissue present in a particular sample. In addition, we formed a group of all cancer samples that contained at least 30% malignant tissue. We summarized the data using one-pole Cole-Cole models that were rigorously fit to the median Dielectric Properties of the three normal tissue groups and one malignant tissue group. In this letter, we present computationally simpler one- and two-pole Debye models that retain the high accuracy of the Cole-Cole models. Model parameters are derived for two sets of frequency ranges: the entire measurement frequency range from 0.5 to 20 GHz, and the 3.1-10.6 GHz FCC band allocated for ultrawideband medical applications. The proposed Debye models provide a means for creating computationally efficient FDTD breast models with realistic wideband Dielectric Properties derived from the largest and most comprehensive experimental study conducted to date on human breast tissue.
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a large scale study of the ultrawideband microwave Dielectric Properties of normal benign and malignant breast tissues obtained from cancer surgeries
Physics in Medicine and Biology, 2007Co-Authors: Mariya Lazebnik, D Popovic, L Mccartney, Cynthia B Watkins, Mary J Lindstrom, Josephine Harter, Sarah Sewall, Travis Ogilvie, Anthony M Magliocco, Tara M BreslinAbstract:The development of microwave breast cancer detection and treatment techniques has been driven by reports of substantial contrast in the Dielectric Properties of malignant and normal breast tissues. However, definitive knowledge of the Dielectric Properties of normal and diseased breast tissues at microwave frequencies has been limited by gaps and discrepancies across previously published studies. To address these issues, we conducted a large-scale study to experimentally determine the ultrawideband microwave Dielectric Properties of a variety of normal, malignant and benign breast tissues, measured from 0.5 to 20 GHz using a precision open-ended coaxial probe. Previously, we reported the Dielectric Properties of normal breast tissue samples obtained from reduction surgeries. Here, we report the Dielectric Properties of normal (adipose, glandular and fibroconnective), malignant (invasive and non-invasive ductal and lobular carcinomas) and benign (fibroadenomas and cysts) breast tissue samples obtained from cancer surgeries. We fit a one-pole Cole–Cole model to the complex permittivity data set of each characterized sample. Our analyses show that the contrast in the microwave-frequency Dielectric Properties between malignant and normal adipose-dominated tissues in the breast is considerable, as large as 10:1, while the contrast in the microwave-frequency Dielectric Properties between malignant and normal glandular/fibroconnective tissues in the breast is no more than about 10%. For more information on this article, see medicalphysicsweb.org
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a large scale study of the ultrawideband microwave Dielectric Properties of normal benign and malignant breast tissues obtained from cancer surgeries
Physics in Medicine and Biology, 2007Co-Authors: Mariya Lazebnik, D Popovic, L Mccartney, Cynthia B Watkins, Mary J Lindstrom, Josephine Harter, Sarah Sewall, Travis Ogilvie, Anthony M Magliocco, Tara M BreslinAbstract:The development of microwave breast cancer detection and treatment techniques has been driven by reports of substantial contrast in the Dielectric Properties of malignant and normal breast tissues. However, definitive knowledge of the Dielectric Properties of normal and diseased breast tissues at microwave frequencies has been limited by gaps and discrepancies across previously published studies. To address these issues, we conducted a large-scale study to experimentally determine the ultrawideband microwave Dielectric Properties of a variety of normal, malignant and benign breast tissues, measured from 0.5 to 20 GHz using a precision open-ended coaxial probe. Previously, we reported the Dielectric Properties of normal breast tissue samples obtained from reduction surgeries. Here, we report the Dielectric Properties of normal (adipose, glandular and fibroconnective), malignant (invasive and non-invasive ductal and lobular carcinomas) and benign (fibroadenomas and cysts) breast tissue samples obtained from cancer surgeries. We fit a one-pole Cole-Cole model to the complex permittivity data set of each characterized sample. Our analyses show that the contrast in the microwave-frequency Dielectric Properties between malignant and normal adipose-dominated tissues in the breast is considerable, as large as 10:1, while the contrast in the microwave-frequency Dielectric Properties between malignant and normal glandular/fibroconnective tissues in the breast is no more than about 10%.
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ultrawideband temperature dependent Dielectric Properties of animal liver tissue in the microwave frequency range
Physics in Medicine and Biology, 2006Co-Authors: Mariya Lazebnik, M C Converse, J H Booske, S C HagnessAbstract:The development of ultrawideband (UWB) microwave diagnostic and therapeutic technologies, such as UWB microwave breast cancer detection and hyperthermia treatment, is facilitated by accurate knowledge of the temperature- and frequency-dependent Dielectric Properties of biological tissues. To this end, we characterize the temperature-dependent Dielectric Properties of a representative tissue type—animal liver—from 0.5 to 20 GHz. Since discrete-frequency linear temperature coefficients are impractical and inappropriate for applications spanning wide frequency and temperature ranges, we propose a novel and compact data representation technique. A single-pole Cole–Cole model is used to fit the Dielectric Properties data as a function of frequency, and a second-order polynomial is used to fit the Cole–Cole parameters as a function of temperature. This approach permits rapid estimation of tissue Dielectric Properties at any temperature and frequency.
Tara M Breslin - One of the best experts on this subject based on the ideXlab platform.
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a large scale study of the ultrawideband microwave Dielectric Properties of normal benign and malignant breast tissues obtained from cancer surgeries
Physics in Medicine and Biology, 2007Co-Authors: Mariya Lazebnik, D Popovic, L Mccartney, Cynthia B Watkins, Mary J Lindstrom, Josephine Harter, Sarah Sewall, Travis Ogilvie, Anthony M Magliocco, Tara M BreslinAbstract:The development of microwave breast cancer detection and treatment techniques has been driven by reports of substantial contrast in the Dielectric Properties of malignant and normal breast tissues. However, definitive knowledge of the Dielectric Properties of normal and diseased breast tissues at microwave frequencies has been limited by gaps and discrepancies across previously published studies. To address these issues, we conducted a large-scale study to experimentally determine the ultrawideband microwave Dielectric Properties of a variety of normal, malignant and benign breast tissues, measured from 0.5 to 20 GHz using a precision open-ended coaxial probe. Previously, we reported the Dielectric Properties of normal breast tissue samples obtained from reduction surgeries. Here, we report the Dielectric Properties of normal (adipose, glandular and fibroconnective), malignant (invasive and non-invasive ductal and lobular carcinomas) and benign (fibroadenomas and cysts) breast tissue samples obtained from cancer surgeries. We fit a one-pole Cole-Cole model to the complex permittivity data set of each characterized sample. Our analyses show that the contrast in the microwave-frequency Dielectric Properties between malignant and normal adipose-dominated tissues in the breast is considerable, as large as 10:1, while the contrast in the microwave-frequency Dielectric Properties between malignant and normal glandular/fibroconnective tissues in the breast is no more than about 10%.
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a large scale study of the ultrawideband microwave Dielectric Properties of normal benign and malignant breast tissues obtained from cancer surgeries
Physics in Medicine and Biology, 2007Co-Authors: Mariya Lazebnik, D Popovic, L Mccartney, Cynthia B Watkins, Mary J Lindstrom, Josephine Harter, Sarah Sewall, Travis Ogilvie, Anthony M Magliocco, Tara M BreslinAbstract:The development of microwave breast cancer detection and treatment techniques has been driven by reports of substantial contrast in the Dielectric Properties of malignant and normal breast tissues. However, definitive knowledge of the Dielectric Properties of normal and diseased breast tissues at microwave frequencies has been limited by gaps and discrepancies across previously published studies. To address these issues, we conducted a large-scale study to experimentally determine the ultrawideband microwave Dielectric Properties of a variety of normal, malignant and benign breast tissues, measured from 0.5 to 20 GHz using a precision open-ended coaxial probe. Previously, we reported the Dielectric Properties of normal breast tissue samples obtained from reduction surgeries. Here, we report the Dielectric Properties of normal (adipose, glandular and fibroconnective), malignant (invasive and non-invasive ductal and lobular carcinomas) and benign (fibroadenomas and cysts) breast tissue samples obtained from cancer surgeries. We fit a one-pole Cole–Cole model to the complex permittivity data set of each characterized sample. Our analyses show that the contrast in the microwave-frequency Dielectric Properties between malignant and normal adipose-dominated tissues in the breast is considerable, as large as 10:1, while the contrast in the microwave-frequency Dielectric Properties between malignant and normal glandular/fibroconnective tissues in the breast is no more than about 10%. For more information on this article, see medicalphysicsweb.org
Di Zhou - One of the best experts on this subject based on the ideXlab platform.
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synthesis and microwave Dielectric Properties of zn3b2o6 ceramics for substrate application
Journal of the American Ceramic Society, 2012Co-Authors: Di Zhou, Hong Wang, Yuehua ChenAbstract:A novel microwave Dielectric ceramics of Zn3B2O6 for substrate application with low sintering temperature was synthesized by the solid-state reaction method. The sintering temperature ranges from 875°C to 950°C. The best microwave Dielectric Properties were obtained in the ceramic sintered at 925°C for 4 h with a permittivity ~6.7, a Q × f value about 58, 500 GHz and a temperature coefficient value of −58 ppm/°C. From the X-ray diffraction, backscattered electron imaging results of the co-fired sample with 20 wt% silver additive, the Zn3B2O6 ceramic was found not to react with Ag at 950°C. The microwave Dielectric Properties and low sintering temperature of Zn3B2O6 ceramic make it a promising candidate for Low temperature co-fired ceramic applications as substrate.
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Dielectric Properties of an ultra low temperature cofiring bi2mo2o9 multilayer
Journal of the American Ceramic Society, 2010Co-Authors: Clive A Randall, Di Zhou, Amanda Baker, Hong Wang, Lixia Pang, Xi YaoAbstract:A Bi2Mo2O9 multilayer ceramic capacitor structure was fabricated in a thick-film process involving tape casting and screen-printing forming techniques. A novel base metal, Al, was used as the internal electrode, and these Dielectrics were co-sintered at 645°C in air. Scanning electron microscopy and energy dispersive spectroscopy (EDS) were used to investigate the local chemical compatibility between the electrode layer and ceramic layer, and no reaction or interdiffusion was found. Dielectric Properties of electroded monolithic ceramic, multilayer, and monolayer samples at 100 Hz–10 MHz in a temperature range of −55°–+175°C were measured; values of the Dielectric Properties were similar to bulk measurements consistent with the absence of any interfacial reaction. Collectively, the data show that it is possible to use the low-temperature firing Bi2Mo2O9 ceramic and Al internal electrode for an ultra-low-temperature cofired ceramic technology.
Jun Liang - One of the best experts on this subject based on the ideXlab platform.
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microwave Dielectric Properties of li2tio3 ceramics doped with zno b2o3 frit
Journal of the American Ceramic Society, 2009Co-Authors: Jun LiangAbstract:A type of new low sintering temperature ceramic, Li2TiO3 ceramic, has been found. Although it is difficult for the Li2TiO3 compound to be sintered compactly at temperatures above 1000°C for the volatilization of Li2O, dense Li2TiO3 ceramics were obtained by conventional solid-state reaction method at the sintering temperature of 900°C with the addition of ZnO–B2O3 frit. The sintering behavior and microwave Dielectric Properties of Li2TiO3 ceramics with less ZnO–B2O3 frit (≤3.0 wt%) doping were investigated. The addition of ZnO–B2O3 frit can lower the sintering temperature of the Li2TiO3 ceramics, but it does not apparently degrade the microwave Dielectric Properties of the Li2TiO3 ceramics. Typically, the good microwave Dielectric Properties of ɛr=23.06, Q×f=32 275 GHz, τf=35.79 ppm/°C were obtained for 2.5 wt% ZnO–B2O3 frit-doped Li2TiO3 ceramics sintered at 900°C for 2 h. The porosity was 0.08%. The Li2TiO3 ceramic system may be a promising candidate for low-temperature cofired ceramics applications.
Hong Wang - One of the best experts on this subject based on the ideXlab platform.
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phase stability low temperature cofiring and microwave Dielectric Properties of bati5o11 ceramics with bacu b2o5 addition
Journal of Materials Science: Materials in Electronics, 2013Co-Authors: Huanfu Zhou, Hong Wang, Liang Fang, Xiaobin Liu, Xiuli ChenAbstract:The effects of BaCu(B2O5) (BCB) additions on the sintering temperature, microstructure and microwave Dielectric Properties of BaTi5O11 modified with 1.0 wt% CuO (BTC) ceramic have been investigated using X-ray diffraction, scanning electron microscopy and Dielectric measurement. The BTC ceramic shows a high sintering temperature (~1,100 °C) and good microwave Dielectric Properties as Q × f = 44,530 GHz, er = 40.5, τf = 39 ppm/°C. The addition of BCB to BTC effectively reduced the sintering temperature from 1,100 to 925 °C. The reduced sintering temperature was attributed to the BCB liquid phase. The BTC ceramic doped with 4 wt% BCB has a good microwave Dielectric Properties with Q × f = 25,502 GHz, er = 37.4, τf = 33.1 ppm/°C. The chemical compatibility of silver electrodes and low-fired samples has also been investigated.
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synthesis and microwave Dielectric Properties of zn3b2o6 ceramics for substrate application
Journal of the American Ceramic Society, 2012Co-Authors: Di Zhou, Hong Wang, Yuehua ChenAbstract:A novel microwave Dielectric ceramics of Zn3B2O6 for substrate application with low sintering temperature was synthesized by the solid-state reaction method. The sintering temperature ranges from 875°C to 950°C. The best microwave Dielectric Properties were obtained in the ceramic sintered at 925°C for 4 h with a permittivity ~6.7, a Q × f value about 58, 500 GHz and a temperature coefficient value of −58 ppm/°C. From the X-ray diffraction, backscattered electron imaging results of the co-fired sample with 20 wt% silver additive, the Zn3B2O6 ceramic was found not to react with Ag at 950°C. The microwave Dielectric Properties and low sintering temperature of Zn3B2O6 ceramic make it a promising candidate for Low temperature co-fired ceramic applications as substrate.
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Dielectric Properties of an ultra low temperature cofiring bi2mo2o9 multilayer
Journal of the American Ceramic Society, 2010Co-Authors: Clive A Randall, Di Zhou, Amanda Baker, Hong Wang, Lixia Pang, Xi YaoAbstract:A Bi2Mo2O9 multilayer ceramic capacitor structure was fabricated in a thick-film process involving tape casting and screen-printing forming techniques. A novel base metal, Al, was used as the internal electrode, and these Dielectrics were co-sintered at 645°C in air. Scanning electron microscopy and energy dispersive spectroscopy (EDS) were used to investigate the local chemical compatibility between the electrode layer and ceramic layer, and no reaction or interdiffusion was found. Dielectric Properties of electroded monolithic ceramic, multilayer, and monolayer samples at 100 Hz–10 MHz in a temperature range of −55°–+175°C were measured; values of the Dielectric Properties were similar to bulk measurements consistent with the absence of any interfacial reaction. Collectively, the data show that it is possible to use the low-temperature firing Bi2Mo2O9 ceramic and Al internal electrode for an ultra-low-temperature cofired ceramic technology.
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low temperature sintering and microwave Dielectric Properties of ba3ti5nb6o28 ceramics with bacu b2o5 additions
Materials Chemistry and Physics, 2009Co-Authors: Huanfu Zhou, Hong Wang, Yuehua Chen, Kecheng LiAbstract:Abstract The effects of BaCu(B2O5) (BCB) additions on the sintering temperature and microwave Dielectric Properties of Ba3Ti5Nb6O28 ceramic have been investigated using dilatometer, X-ray diffraction, scanning electron microscopy and Dielectric measurement. The pure Ba3Ti5Nb6O28 ceramic shows a high sintering temperature (∼1250 °C) and good microwave Dielectric Properties as Q × f of 11,400 GHz, ɛr of 37.0, τf of −8 ppm °C−1. It was found that the addition of BCB to Ba3Ti5Nb6O28 could lower the sintering temperature from 1250 to 925 °C. The reduced sintering temperature was attributed to the BCB liquid phase. The addition of BCB also enhanced the microwave Dielectric Properties to Q × f of 19,191 GHz, ɛr of 38.2, τf of 12 ppm °C−1.
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structures phase transformations and Dielectric Properties of pyrochlores containing bismuth
Journal of the American Ceramic Society, 2005Co-Authors: Xiaoli Wang, Hong Wang, Xi YaoAbstract:The structures, phase transformations, and Dielectric Properties of pyrochlore ceramics containing bismuth were studied. The relation between the orthorhombic and cubic pyrochlores in the Bi2O3-ZnO-Nb2O5 (BZN) system has been investigated. The effect of bismuth in distorted cubic pyrochlore structures is discussed. BZN compositions with pyrochlore structures have excellent Dielectric Properties, very low Dielectric loss, and high Dielectric constants with stable frequency and temperature dependence.
