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Journal of Forestry Research 2015年第3期26卷 777-783页

作者： Xinyu Chen Huwei Yuan Xiange Hu Jingxiang Meng Xianqing Zhou Xiao-Ru Wang Yue Li National Engineering Laboratory for Forest Tree Breeding Key Laboratory of Genetic and Breeding in Forest Trees and Ornamental Plants of Ministry of Education College of Biological Sciences and Technology Beijing Forestry University State-owned Forest Farm in Hebei Province Department of Ecology and Environmental Science UmeUniversity SE-901 87 Ume Sweden

electrical impedance （El） and phase angle （PHI） parameters in AC impedance spectroscopy are important electrical parameters in the study of medical pathology. However, little is known about their application in variation and genetic relationship studies of forest trees. In order to test whether impedance parameters could be used in genetic relationship analysis among conifer species, E1 and PHI were measured in a seedling experiment test composed of Pinus tabuliformis, Pinus yunnanensis, and Pinus densata in a habitat of Pinus tabuliformis. The results showed that variations in both EI and PHI among species were sig- nificant in different electric frequencies, and the EI and PHI values measured in the two populations of P. densata were between the two parental species, P. yunnanensis and P. tabuliformis. These results show that these two impedance parameters could reflect the genetic relationship among pine species. This was the first time using the two AC impedance spectroscopy parameters to test the genetic relationship analysis between tree species, and would be a hopeful novelreference methodology for future studies in evolution and genetic variation of tree species.

关键词： electrical impedance Phase angle Pinustabuliformis Pinus yunnanensis . Pinus densata . Seedlingneedle Genetic variation

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Non-destructive experimental testing and modeling of electrical impedance behavior of untreated and treated ultra-soft clayey soils

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第3期9卷 161-168页

作者： Aram M.Raheem Cumaraswamy Vipulanandan Mohammad S. Joshaghani Department of Civil Engineering University of Kirkuk Kirkuk Iraq Department of Civil and Environmental Engineering University of Houston Houston TX USA

The characterization of ultra-soft clayey soil exhibits extreme challenges due to low shear strength of such ***,inspecting the non-destructive electrical impedance behavior of untreated and treated ultra-soft clayey soils gains more *** shear strength and electrical impedance were measured experimentally for both untreated and treated ultra-soft clayey *** shear strength of untreated ultra-soft clayey soil reached 0.17 kPa for 10% bentonite content,while the shear strengths increased to 0.27 kPa and 6.7 kPa for 10% bentonite content treated with 2% lime and 10% polymer,*** electrical impedance of the ultra-soft clayey soil has shown a significant decrease from 1.6 kΩ to 0.607 kΩ when the bentonite content increased from 2% to 10% at a frequency of 300 ***10%lime and 10% polymer treatments have decreased the electrical impedances of ultra-soft clayey soil with 10%bentonite from 0.607 kΩ to 0.12 kΩ and 0.176 kΩ,respectively,at a frequency of 300 kHz.A new mathematical model has been accordingly proposed to model the non-destructive electrical impedancefrequency relationship for both untreated and treated ultra-soft clayey *** new model has shown a good agreement with experimental data with coefficient of determination（R;）up to 0.99 and root mean square error（RMSE） of 0.007 kΩ.

关键词： Ultra-soft clayey soil Bentonite Lime Polymer Shear strength Non-destructive testing electrical impedance

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Assessing the supercooling of fresh-cut onions at−5℃ using electrical impedance analysis

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Food Quality and Safety 2020年第2期4卷 55-58页

作者： Shoji Koide Ami Yoneyama Takahiro Orikasa Matsuo Uemura Faculty of Agriculture Iwate UniversityMoriokaJapan Iwate Agri-Innovation Center Iwate UniversityMoriokaJapan

We supercooled fresh-cut onion at−5℃ for 12 *** supercooling,the electric impedance properties of the samples were evaluated by electrical impedance spectroscopy over the frequency range of 42 Hz−5 *** time-temperature profiles of samples indicated that the freezing point and supercooling point were−2.3℃±0.7℃ and−6.9℃±1.0℃,*** results indicated that 34 of the 36 supercooled samples exhibited a definite circular arc in the Cole-Cole plot,which suggested that the cell membrane remained intact during *** the other two samples which did not exhibit a definite circular arc,the cell membrane had sustained serious damage during ***,there was large difference in drip loss percentage between supercooled samples exhibited a definite circular arc in the Cole-Cole plot and samples not exhibiting a definite circular *** results suggest that fresh-cut onions can be supercooled at−5℃.

关键词： supercooling fresh-cut onion electrical impedance Cole-Cole plot supercooling point

Application　of　electrical　impedance　Principle　in　the　Diagnosis　of　Diaphragm　Fatigue

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Journal of Huazhong University of Science and Technology(Medical Sciences) 1995年第4期15卷 227-230,237页

作者：牛汝楫 Institute of Respiratory Diseases Tongji Hospital Tongji Medical University Wuhan

The chest and abdomen impedance respirographs (IRG) , including the one dimensional IRG and the two dimensional IRG were designed and produced by applying the principle of bioelectrical impedance. Using IRG the non-synchronized chest and abdomen respiratory motions occurring in diaphragmatic fatigue were measured. The results showed that all 203 normal controls showed synchronized style of chest and abdomen respiratory motions. In 189 COPD patients 117 (61.9%) showed non-synchronized respiratory motions which could be further divided into three types: type Ⅰ showed complete contra-directional respiratory movements of chest and abdomen respiration, with M>24 % and a angle>120°; type Ⅱ showed staggered peak of the chest and abdomen motion curves (13 %

关键词： electrical impedance diaphragm fatigue COPD

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Interspecific Variation and Phylogenic Architecture of Pinus densata and the Hybrid of Pinus tabuliformis×Pinus Yunnanensis in the Pinus densata Habitat:an electrical impedance Spectra Perspective

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Journal of Botanical Research 2021年第1期3卷 1-15页

作者： Fengxiang Ma Xiaoyang Chen Yue Li School of Sciences Beijing Forestry UniversityBeijing 100083China College of Forestry and Landscape Architecture South China Agricultural UniversityGuangzhouGuangdong 510642China National Engineering Laboratory for Forest Tree Breeding Key Laboratory for Genetics and Breeding of Forest Trees and Ornamental Plants of Ministry of EducationBeijing Forestry UniversityBeijing 100083China

We evaluated a novel and non-destructive method of the electrical impedance spectroscopy(EIS)to elucidate the genetic and evolutionary relationship of homoploid hybrid conifer of Pinus densata(P.d)and its parental species Pinus tabuliformis(P.t)and Pinus yunnanensis(P.y),as well as the artificial hybrids of the P.t and *** common garden tests of96 trees sampled from 760 seedlings and 480 EIS records of 1,440 needles assessed the interspecific variation of the P.d,P.t,P.y and the artificial *** found that(1)EIS at different frequencies diverged significantly among germplasms;P.y was the highest,P.t was the lowest,and their artificial hybrids were within the range of P.t and P.y;(2)maternal species effect of EIS magnitudes in the hybrids and P.d was stronger than the paternal species characteristics;(3)EIS of the artificial hybrid confirmed the mid-parent and partial maternal species characteristics;(4)unified exponential model of EIS for the interspecific and hybrids can be constructed as|Z|=Af^(-B);(5)cluster analysis for species and hybrid combinations in total corroborated with the previous hybrid model of Pinus *** non-destructive EIS method complemented the previous finding that Pinus densata was originated from P.t and *** conclude that the impedance would be a viable indicator to investigate the interspecific genetic variations of conifers.

关键词： Pinus densata Artificial hybrid electrical impedance Interspecific genetic variation Homoploid hybrid

Assessment of regional ventilation distribution:Comparison of vibration response imaging with electrical impedance tomography

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Assessment of regional ventilation distribution:Comparison o...

YBa2Cu3O7-y氧化物超导体在不同电流密度下的电阻转变特性

中国毒理学会第六届全国毒理学大会

作者： SHI Chang Stefan BOEHME Alexander H BENTLEY Erik K HARTMANN Klaus U KLEIN Marc BODENSTEIN Roman ULLRICH Klaus MARKSTALLER Department of Anaesthesiology Medical Centre of the Johannes Gutenberg-University Mainz National Beijing Center for Drug Safety Evaluation and Research Beijing Institute of Pharmacology and Toxicology

＜正＞OBJECTIVE Vibration response imaging（VRI） is a new bedside technology to monitor ventilation by detecting lung sound *** is currently unknown whether VRI is able to accurately monitor the local distribution of ventilation within the *** therefore compared VRI to electrical impedance tomography（EIT）,an established technique used for the assessment of regional ventilation. METHODS For peer review,simultaneous EIT and VRI measurements were performed in the healthy and injured lungs（ALI;induced by saline lavage） at different PEEP levels（0,5,10,15 mbar） in nine *** energy amplitude（VEA） by VRI,and amplitudes of relative impedance changes（rel. AZ） by EIT,were evaluated in seven regions of interest（ROIs）.To assess the distribution of VT by VRI and EIT,absolute values were normalized to the VT obtained by simultaneous spirometry measurements. RESULTS Redistribution of ventilation by ALI and PEEP was detected by VRI and *** linear correlation between pooled VT by VEA and *** was R =***-Altman analysis showed a bias of -1.07±24.71 ml and limits of agreement of -49.05 to +47.36 *** the different ROIs, correlations of VT - distribution by EIT and VRI ranged between R values ofO.29 and *** and PEEP did not alter the agreement of VT between VRI and *** Measurements of regional ventilation distribution by VRI are similar to those obtained by EIT.

关键词： electrical impedance lung injury ventilation vibration imaging

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陕西师大学报(自然科学版) 1988年第4期 87-88页

作者：仝天魁孙凤林卢克箴董诠键陕西师大物理系

1 同一电流密度下的电阻特性YBa2Cu3O7-y超导体（Φ10×2.5）采用四引线法测量电阻,电极间隔为1.5m,测量表明,对于名义成份为 YBa2Cu3O7-y,的样品,室温电阻约为5Ω,电阻随温度降低而减小.图1是恒流为20mA 的 R—T 曲线.温度在128k 以上... 详细信息

1 同一电流密度下的电阻特性YBa2Cu3O7-y超导体（Φ10×2.5）采用四引线法测量电阻,电极间隔为1.5m,测量表明,对于名义成份为 YBa2Cu3O7-y,的样品,室温电阻约为5Ω,电阻随温度降低而减小.图1是恒流为20mA 的 R—T 曲线.温度在128k 以上样品呈金属行为;当温度降到128k 时,电

关键词： superconductor electrical impedance initial transition temperature