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六边形环复合吸波超材料性能的等效电路分析方法

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电子与信息学报 2018年第8期40卷 1873-1878页

作者：于家傲彭世蕤陈晓坤李有权空军预警学院六系武汉430019 华中农业大学理学院武汉430070

该文提出一种针对六边形环复合吸波超材料吸波性能的等效电路分析方法。基于六边形环谐振特性建立了等效电路模型,通过对六边形点阵分布的傅里叶分析,提出了等效分布周期参数,给出了基于模型尺寸的RLC参数提取方法。与全波仿真结果比较... 详细信息

该文提出一种针对六边形环复合吸波超材料吸波性能的等效电路分析方法。基于六边形环谐振特性建立了等效电路模型,通过对六边形点阵分布的傅里叶分析,提出了等效分布周期参数,给出了基于模型尺寸的RLC参数提取方法。与全波仿真结果比较,所提出的等效电路模型对分析多种尺寸的六边形环复合吸波材料具有较好的适用性和准确性。通过样品制作和测量,进一步验证了该模型的有效性,最后实现了一款工作于1.7~5.7 GHz的宽带雷达吸波材料。

关键词：复合吸波超材料等效电路模型六边形环宽带雷达吸波材料

双六边形环电路模拟吸波材料及其等效电路模型

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国防科技大学学报 2019年第3期41卷 153-158页

作者：于家傲彭世蕤刘立国李有权空军预警学院信息对抗系湖北武汉430019 海军工程大学电子工程学院湖北武汉430019

提出以双六边形环为单元结构的电路模拟吸波材料。根据单元的双频特性建立等效电路模型,根据六边形环周期分布规律提出等效周期概念,给出等效分布电参数的计算方法。利用该模型对双六边形环电路模拟吸波材料的结构进行参数分析,并与HFS... 详细信息

提出以双六边形环为单元结构的电路模拟吸波材料。根据单元的双频特性建立等效电路模型,根据六边形环周期分布规律提出等效周期概念,给出等效分布电参数的计算方法。利用该模型对双六边形环电路模拟吸波材料的结构进行参数分析,并与HFSS全波分析结果进行对比,验证该方法的准确性。加工样品和实测,结果发现所设计吸波材料在1.9~8.9 GHz频段内对正入射波具有良好的吸波特性,实测结果与等效电路模型仿真结果吻合较好,进一步验证了该方法的有效性。

关键词：电路模拟吸波材料双六边形环等效电路模型

Simple Biochemical Detection and 16S rRNA-Based analysis of veterinary Salmonella enterica

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In vitro infection of bovine and ovine red blood cells with Theileria annulata schizonts

第四届全国牛病防制及产业发展大会

作者： Qiwei Chen Xiaowei Gong Fuying Zheng Xiaoan Cao Hong Yin youquan li Jizhang Zhou State Key Laboratory of Veterinary Etiological Biology Key Laboratory of Veterinary Public Health of Ministry of AgricultureLanzhou Veterinary Research InstituteChinese Academy of Agricultural Sciences

In this study,we provide more rapid,unambiguous identification of Salmonella enterica.A total of seventeen isolates of Salmonella（***）enterica were identified from swine（n=7）,cattle（n=5）and sheep（n=5）from *** isolates were confirmed as *** by 16S rRNA sequence analysis and traditional Biochemical profiling identification,which was the combination of two methods in order to promote meaningful and scientifically accurate communications with identified isolates.

关键词： Salmonella enterica 16S rRNA Biochemical Detection Rapid identification

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In vitro infection of bovine and ovine red blood cells with ...

中国奶业协会第26次繁殖学术年会暨国家肉牛牦牛/奶牛产...

作者： youquan li Guiquan Guan Zhijie liu Jifei Yang Qingli Niu Jianxun Luo Hong Yin State Key Laboratory of Veterinary Etiological Biology Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Science

Theileria annulata,the causative agents of tropical theileriosis,is protozoan parasites that cause lymphoproliferative diseases of *** vivo,parasitized cells undergo clonal expansion and in?Itrate both lymphoid and non-lymphoid tissues of the infected *** this study,in vitro infection of bovine and ovine red blood cells with Theileria annulata schizonts is firstly carried *** experiments showed that Theileria annulata schizonts can infect bovine red blood cells from cattle 2 and cattle 30 in vitro,and also infect ovine red blood cells from sheep 2 and sheep 82 in ***,*** schizonts can infect both bovine red blood cells and ovine red blood cells in *** proliferation of Theileria annulata schizonts-infected lymphocytes is obviously suppressed by bovine red blood cells and ovine red blood *** schizonts could provide an intriguing model for the study of parasite-host interactions in vitro in the future.

关键词： In vitro infection bovine red blood cells ovine red blood cells Theileria annulata schizonts

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利用PLC和变频器进行速度同步控制

电气传动 2000年第5期30卷 6-7页

作者：李友泉詹永麒上海交通大学

本文就传动系统中速度同步控制进行了简要说明 ,通过实例介绍了利用可编程控制器 (PL C)

关键词：变频器速度同频控制电气传动系统 PLC

Probiotics isolated from animals in Northwest China improve the intestinal performance of mice

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^(68)Gallium-labelled PSMA-PET/CT as a diagnostic and clinical decision-making tool in Asian prostate cancer patients following prostatectomy

2021中国畜牧兽医学会兽医寄生虫学分会第二届青年科学家学术论坛

作者： Yingying li Dan Jia Jiahui Wang Hehai li Xijuan Yin Junlong liu Jinming Wang Guiquan Guan Jianxun Luo Hong Yin Sa Xiao youquan li

Antibiotic resistance is an increasingly prevalent problem *** are live microorganisms that provide health benefits to human beings and animals and also antimicrobial activity against pathogens and might be an antibiotic *** gastrointestinal tract of animals can be a suitable source of finding novel antimicrobial agents,where the vast majority of gut microbes inhabit and a plurality of antimicrobial producers exhibit either a wide or narrow *** that live in Northwest China might possess a special commensal community in the ***,the purpose of this study was to assess the effects of three probiotic strains(including Lactobacillus salivarius ZLP-4 b from swine,Lactobacillus plantarum FBL-3 a from beef cattle,and Bacillus velezensis JT3-1 from yak),which were isolated from livestock in this area,on the overall growth performance,immune function,and gut microbiota of *** results showed that the *** ZLP-4 b group not only improved the growth performance but also amended the intestinal mucosa morphology of ***,the supplementation of *** FBL-3 a and *** ZLP-4 b strains significantly increased the content of anti-inflammatory cytokines IL-4 and IL-10 but decreased the pro-inflammatory factor IL-17 *** levels of pro-inflammatory factors IL-6,IL-17 A,and TNF-α were also decreased by the *** JT3-1 group *** 16 S rDNA sequence results showed that the probiotic administration could increase the proportion of Firmicutes/Bacteroidetes intestinal microbes in ***,the relative abundance of Lactobacillus was boosted in the JT3-1-and ZLP-4 b-treated groups,and that of opportunistic pathogens(including Proteobacteria and Spirochaetes) was diminished in all treated groups compared with the control *** conclusion,*** JT3-1 and *** ZLP-4 b supplementation enhanced the overall performance,intestinal epithelial mucosal integrity,and immune

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Cancer Biology & Medicine 2019年第1期16卷 157-165页

作者： Janice S.H.Tan Charles X.Y.Goh Yen Sin Koh youquan li Jeffrey K.L.Tuan Eu Tiong Chua Terence W.K.Tan Michael L.C.Wang Lui Shiong Lee Kae Jack Tay Ravindran Kanesvaran Chee Keong Toh Aaron K.T.Tong Winnie W.C.Lam Melvin L.K.Chua Division of Radiation Oncology National Cancer Centre Singapore Department of Nuclear Medicine and Molecular Imaging Singapore General Hospital Radiological Sciences Academic Clinical Programme Duke-NUS Medical School Oncology Academic Clinical Programme Duke-NUS Medical School Department of Urology Singapore General Hospital Department of Surgery Sengkang General Hospital Division of Medical Oncology National Cancer Centre Singapore Division of Medical Sciences National Cancer Centre Singapore

Objective: Prostate cancers(PCa) in Asian individuals are molecularly distinct from those found in their Caucasian *** is no risk stratification tool for Asian men with rapid biochemical recurrence(BCR) following radical prostatectomy(Rad P). This study aims to assess the detection rate of ^(68)Ga-prostate-specific membrane antigen-positron emission tomography/computed tomography(PSMA-PET/CT) for diagnosis of clinical recurrence and as a treatment decision making tool in Asian patients with BCR post-Rad ***: ^(68)Ga PSMA-PET and CT body with/without bone scan [conventional workup(CWU)] were performed in 55 Asian patients with BCR within 36 months post-Rad P. Two blinded reviewers assessed the images. Detection rates of ^(68)Ga PSMAPET/CT were evaluated, and impact on management was reviewed by comparison with ***: Median time to BCR post-Rad P was 8.1 months. Detection rate for ^(68)Ga PSMA-PET/CT was 80%(44/55). A positive scan was significantly associated with increasing prostate-specific antigen(PSA) level [odds ratio(OR) = 1.13(95% CI 1.05–1.30), P =0.017], but not with higher Gleason grade or shorter PSA doubling time. Compared to CWU, ^(68)Ga PSMA-PET/CT detected an additional 106 lesions in 33/44 patients with a positive scan, resulting in a change in management in 25/44(56.8%) patients: 10 to hormonal therapy(HT) and whole pelvis radiotherapy(RT) in addition to bed RT, and 15 to palliative HT ***: In the present report, we demonstrated the diagnostic and treatment decision utility of ^(68)Ga PSMA-PET/CT in Asian men with rapid BCR. Detection of small volume nodal and systemic recurrences at low PSA levels(lights the role of the tool in assigning patients to treatment intensification with HT-RT or palliative HT in polymetastatic disease.

关键词： ^68Ga PSMA PET/CT prostate cancer Asian diagnostic recurrence prostatectomy salvage radiotherapy

利用试井技术确定低渗透油藏CO2驱替前缘的方法

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油气地质与采收率 2020年第1期27卷 120-125页

作者：李友全阎燕于伟杰中国石化胜利油田分公司勘探开发研究院

为了认识CO2驱替过程中压力响应特征,确定驱替前缘位置,进行了CO2驱替前缘试井解释方法研究。考虑CO2驱油机理、低渗透油藏启动压力梯度、储层非均质性等因素的影响,建立了低渗透油藏多组分CO2驱试井模型。采用非结构化网格进行网格剖分... 详细信息

为了认识CO2驱替过程中压力响应特征,确定驱替前缘位置,进行了CO2驱替前缘试井解释方法研究。考虑CO2驱油机理、低渗透油藏启动压力梯度、储层非均质性等因素的影响,建立了低渗透油藏多组分CO2驱试井模型。采用非结构化网格进行网格剖分,基于有限体积方法,利用牛顿迭代进行全隐式求解。根据流动形态特征,将试井曲线划分为井筒存储段、过渡段、CO2区平面径向流动段、CO2波及区流动段和CO2未波及区流动段等5个主要阶段。通过追踪流体性质变化对试井曲线的影响,进一步研究了CO2浓度变化对压力的影响,建立了驱替前缘确定方法。矿场应用实践表明,该方法可分析CO2驱替前缘位置,预测前缘推进状况,为认识低渗透油藏CO2驱开发规律和优化开发方案提供了有效手段。

关键词： CO2驱试井模型数值试井压力监测驱替前缘低渗透油藏

房颤患者CCTA左心耳充盈缺损中血栓征象分析

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临床放射学杂志 2023年第11期42卷 1741-1746页

作者：刘家骥王倩李有权陈剑方进遵义市第一人民医院/遵义医科大学第三附属医院影像科 563000 遵义市第一人民医院/遵义医科大学第三附属医院心内科 563000

目的研究心房颤动(AF)患者心脏CT血管造影(CCTA)左心耳(LAA)充盈缺损病例中提示左心耳血栓(LAAT)的影像征象。方法搜集行CCTA检查并出现LAA充盈缺损的AF患者64例,分析充盈缺损区与正常密度心腔交界面的形状、走行和清晰度,充盈缺损区密... 详细信息

目的研究心房颤动(AF)患者心脏CT血管造影(CCTA)左心耳(LAA)充盈缺损病例中提示左心耳血栓(LAAT)的影像征象。方法搜集行CCTA检查并出现LAA充盈缺损的AF患者64例,分析充盈缺损区与正常密度心腔交界面的形状、走行和清晰度,充盈缺损区密度均匀度,环绕征、飘带征等征象,与最终结果对照,分析上述征象诊断LAA的敏感度(TPR)、特异度(TNR)、阳性预测值(PPV)、阴性预测值(NPV)。结果64例最终诊断LAAT 27例,所有征象中,交界面走行的TPR(100%)和NPV(100%)最高,TNR(59%)较低;环绕征的TNR(100%)和PPV(100%)最高,TPR(33%)较低,交界面形状的TPR(78%)和TNR(73%)最为均衡;飘带征TPR(11%)和TNR(70%)均较低,但征象特殊;通过交界面形状与清晰度两征象联合应用,可显著提高TNR(95%)和PPV(90%),而交界面形状、清晰度与密度均匀度三征象联合应用,可获得除环绕征外最佳的TNR(97%)和PPV(94%)。结论对LAA出现充盈缺损的AF患者重点从交界面走行、形态、清晰度、密度均匀度进行综合分析,交界面走行呈曲面且形态不规则、密度不均匀,是LAAT的高风险征象,环绕征是LAAT的特异性征象;飘带征可能预示LAA处于高凝状态,值得进一步研究。

关键词：心房颤动心脏CT 左心耳血栓