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双频双极化频率选择表面

电子与信息学报 2007年第2期29卷 506-508页

作者：高强闫敦豹袁乃昌付云起国防科技大学微波技术发展中心长沙410073

该文对分形的频率选择表面的特性进行了详细地研究。由于分形包含初始形状的很多比例,谐振也具有分形的比例,同时加上形状的对称性,所以双频双极化频率选择表面就得以实现。利用周期矩量法设计了几种频率选择表面,仿真和实验结果基本相... 详细信息

该文对分形的频率选择表面的特性进行了详细地研究。由于分形包含初始形状的很多比例,谐振也具有分形的比例,同时加上形状的对称性,所以双频双极化频率选择表面就得以实现。利用周期矩量法设计了几种频率选择表面,仿真和实验结果基本相吻合。

关键词：频率选择表面分形周期矩量法

Universal paradigm of ternary metacomposites with tunable epsilon-negative and epsilon-near-zero response for perfect electromagnetic shielding

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Rare Metals 2024年第2期43卷 796-809页

作者： yun-Peng Qu yun-Lei Zhou Yang Luo Yao Liu Jun-Fei Ding Yan-Li Chen Xiu Gong Jing-Liang Yang qiong Peng Xiao-Si qi College of Physics Guizhou UniversityGuiyang550025China Hangzhou Institute of Technology Xidian UniversityHangzhou311231China Department of Materials ETH Zurich8093ZurichSwitzerland Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan250061China

CaCu_(3)Ti_(4)O_(12)(CCTO)ceramic nanocomposites incorporating graphene–carbon black(GRCB)fillers were fabricated by spark plasma sintering *** percolative effects of conductive GRCB fillers on dielectric response of GRCB/CCTO ternary metacomposites were systematically *** weakly real permittivity(ε′)-negative response(ε′~−1×10^(2))was achieved which originated from weakly low-frequency plasmonic state of free carriers within constructed GRCB *** enhancing three-dimensional GRCB network,the plasma frequency of metacomposites increased while the damping factor ***,theε′-negative values of metacomposites were tuned from−10^(2) to−10^(4) orders of magnitude andε′-near-zero(ENZ)frequencies from~142 to~340 MHz which substantially benefited from the moderate carrier concentration of GRCB dual *** Drude model and equivalent circuit models were adopted to demonstrate dielectric and electrical *** obtained metacomposites show strong EM shielding effect along with enhanced plasmonic oscillation and even better achieving perfect EM shielding effect in ENZ *** work achieves the tunableε′-negative andε′-near-zero response and more importantly clarifies its regulation mechanism in ceramic-based ternary metacomposites,which opens up the possibility of designing high-performance EM shielding materials based on metacomposites.

关键词： Metacomposites Ceramic matrix composites Negative permittivity Epsilon-near-zero Electromagnetic shielding

幅相同调的吸波-对消雷达散射截面减缩超表面设计

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物理学报 2022年第8期71卷 90-99页

作者：袁方毛瑞棋高冕郑月军陈强付云起国防科技大学电子科学学院长沙410073

更宽的工作频带和更低的雷达散射截面(radar cross section,RCS)一直是低可探测领域研究的热点,然而这两者往往难以兼顾.鉴于此,本文提出了一种幅相同调的吸波-对消RCS减缩超表面,通过在宽带范围内同时设计两个单元的反射相位和反射幅度... 详细信息

更宽的工作频带和更低的雷达散射截面(radar cross section,RCS)一直是低可探测领域研究的热点,然而这两者往往难以兼顾.鉴于此,本文提出了一种幅相同调的吸波-对消RCS减缩超表面,通过在宽带范围内同时设计两个单元的反射相位和反射幅度,使目标RCS在空间域和能量域分别获得10 d B以上减缩,从而通过叠加获得20 d B以上的宽带RCS减缩.仿真和实验结果表明,在两种极化下,幅相同调的吸波-对消RCS减缩超表面可以在6.10—12.15 GHz频带范围内获得20 d B以上的RCS减缩效果,同时10 d B减缩带宽为4.3—14.2 GHz.所设计的超表面具有减缩幅度大、减缩频带宽、质量轻、单层结构、极化稳定性好、柔性易共形等优点,有望为低可探测材料研制以及低可探测装备性能提升提供新的技术途径.

关键词：雷达散射截面减缩超表面幅相同调吸波相位对消

Safety and efficacy of transcatheter arterial embolization in autosomal dominant polycystic kidney patients with gross hematuria: Six case reports

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World Journal of Clinical Cases 2024年第11期12卷 1954-1959页

作者： Wei-Fan Sui yun-Xin Duan Jian-yun Li Wei-Bin Shao Jian-Hua fu Department of Interventional Radiology Zhenjiang First People's HospitalZhenjiang 212000Jiangsu ProvinceChina Department of Nephrology Zhenjiang First People’s HospitalZhenjiang 212000Jiangsu ProvinceChina

BACKGROUND To retrospectively report the safety and efficacy of renal transcatheter arterial embolization for treating autosomal dominant polycystic kidney disease(ADPKD)patients with gross *** SUMMARY The purpose of this study is to retrospectively report the safety and efficacy of renal transcatheter arterial embolization for treating ADPKD patients with gross *** and methods:During the period from January 2018 to December 2019,renal transcatheter arterial embolization was carried out on 6 patients with polycystic kidneys and gross *** arteriography was performed first,and then we determined the location of the hemorrhage and performed embolization under digital subtraction angiography *** in routine blood test results,routine urine test results,urine color and postoperative reactions were observed and ***:Renal transcatheter arterial embolization was successfully conducted in 6 *** indices of 5 patients and the color of gross hematuria improved after surgery compared with before *** severe complication reactions *** For autosomal dominant polycystic kidney syndrome patients with gross hematuria,transcatheter arterial embolization was safe and effective.

关键词： Renal artery Autosomal dominant polycystic kidney disease Gross hematuria Interventional radiology Embolization Case report

Prognostic Nutritional Index Associates with the Severity of Silicosis:A Study from a Tertiary Class A Prevention and Treatment Institute for Occupational Diseases in China

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Biomedical and Environmental Sciences 2024年第1期37卷 122-126页

作者： HE La Gu LIANG yun Lai YANG Lu qi YUAN Hua Min Medical laboratory Department Hunan Prevention and Treatment Institute for Occupational DiseasesChangsha 410000HunanChina Laboratory Medicine Department Xiangya HospitalCentral South UniversityChangsha 410013HunanChina

Pneumoconiosis is a group of heterogeneous fibrotic lung diseases caused by inorganic mineral dust and includes coal workers’pneumoconiosis and *** involves diffuse or nodular interstitial pulmonary fibrosis caused by exposure to asbestos or silica *** is thought to have the highest number of silicosis cases,with 6,000 new cases reported annually^([1]).Currently,the clinical diagnosis and monitoring of silicosis relies mainly on a history of occupational exposure and radiological abnormalities^([2]).Therefore,determining further indicators is crucial to reflect the severity of silicosis.

关键词： diagnosis lung diseases

A functionalized activated carbon adsorbent prepared from waste amidoxime resin by modifying with H_(3)PO_(4) and ZnCl_(2) and its excellent Cr(Ⅵ)adsorption

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 585-598页

作者： Chunlin He yun Liu Mingwei qi Zunzhang Liu Yuezhou Wei Toyohisa fujita Guifang Wang Shaojian Ma Wenchao Yang School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi UniversityNanning 530004China School of Nuclear Science and Technology University of South ChinaHengyang 421000China School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of New Low-carbon Green Chemical Technology Education Department of Guangxi Zhuang Autonomous RegionNanning 530004China

With the application of resins in various fields, numerous waste resins that are difficult to treat have been produced. The industrial wastewater containing Cr(Ⅵ) has severely polluted soil and groundwater environments, thereby endangering human health. Therefore, in this paper, a novel functionalized mesoporous adsorbent PPR-Z was synthesized from waste amidoxime resin for adsorbing Cr(Ⅵ). The waste amidoxime resin was first modified with H3PO4 and ZnCl_(2), and subsequently, it was carbonized through slow thermal decomposition. The static adsorption of PPR-Z conforms to the pseudo-second-order kinetic model and Langmuir isotherm, indicating that the Cr(Ⅵ) adsorption by PPR-Z is mostly chemical adsorption and exhibits single-layer adsorption. The saturated adsorption capacity of the adsorbent for Cr(Ⅵ) could reach 255.86 mg/g. The adsorbent could effectively reduce Cr(Ⅵ) to Cr(Ⅲ) and decrease the toxicity of Cr(Ⅵ) during adsorption. PPR-Z exhibited Cr(Ⅵ) selectivity in electroplating wastewater. The main mechanisms involved in the Cr(Ⅵ) adsorption are the chemical reduction of Cr(Ⅵ) into Cr(Ⅲ) and electrostatic and coordination interactions. Preparation of PPR-Z not only solves the problem of waste resin treatment but also effectively controls Cr(Ⅵ) pollution and realizes the concept of “treating waste with waste”.

关键词： waste amidoxime resin mesoporous adsorbent H_(3)PO_(4)and ZnCl_(2)processing Cr(VI)adsorption electroplating wastewater

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新型电磁带隙结构加载的微带天线阵

国防科技大学学报 2010年第4期32卷 68-71,77页

作者：李有权张光甫付云起袁乃昌国防科技大学电子科学与工程学院湖南长沙410073

研究了以EBG结构为衬底的微带天线阵。将EBG结构置于微带天线阵的底部取代微带天线阵列的金属底板,不仅能增加天线带宽,还能提高天线阵的增益。测试结果表明,天线单元带宽从3.81%提高到8.86%,在工作频带内天线阵增益都在10dB以上,同时... 详细信息

研究了以EBG结构为衬底的微带天线阵。将EBG结构置于微带天线阵的底部取代微带天线阵列的金属底板,不仅能增加天线带宽,还能提高天线阵的增益。测试结果表明,天线单元带宽从3.81%提高到8.86%,在工作频带内天线阵增益都在10dB以上,同时天线单元间的耦合系数也得到有效降低。

关键词：微带天线阵电磁带隙结构耦合系数带宽增益

Current status and future development of aortic stent fenestration-assisted techniques

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Chinese Medical Journal 2024年第6期137卷 752-754页

作者： Gezheng Chen Xiaoyu qi Wanying Wu Dongsheng fu Li qin Chao Yang Department of Vascular Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430022China Department of Vascular Surgery Nanjing Drum Tower HospitalAffiliate Hospital of Nanjing University Medical SchoolNanjingJiangsu 210008China

To the Editor:In 1996,Parodi et al^([1])introduced the technique of fenestrated endovascular aneurysm repair(f-EVAR)for treatment of pararenal abdominal aortic *** use physician modified stent grafts(PMSGs)for fenestration,which allows for stent grafts to gain sufficient proximal sealing zones and maintain the blood perfusion of visceral arteries.^([2])Stent grafts used in the f-EVAR technique developed from PMSGs to Company Modified Devices(CMDs)and off-the-shelf devices.^([3])To improve the precision of PMSGs and shorten the time of stent graft modification,various techniques that assist in the process of fenestration have been researched and developed,including 3-dimensional(3D)printing technique,the Mixed Reality(MR)technique,and the 3D parametric surface planar topological guide *** article describes the current status and future development of these techniques.

关键词： aortic perfusion arteries

Electrochemical chemoselective thiocarbamylation of late-stage Tyr-containing drugs and peptides

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Science China Chemistry 2024年第10期67卷 3382-3388页

作者： Wan-Jie Wei Xin-Yu Wang Hai-Tao Tang Fei-Hu Cui yun-qi Wu Ying-Ming Pan State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China)Collaborative Innovation Center for Guangxi Ethnic MedicineSchool of Chemistry and Pharmaceutical SciencesGuangxi Normal University

The synthesis and modification of peptides occupy a unique position in the field of drug development, and the functionalization of amino acids is a valuable strategy as an alternative to peptide modification. Currently, the development of tyrosine(Tyr) as a target amino acid is a major challenge in the field of chemistry. Herein, we report an electrochemical radical coupling reaction of labeling tyrosine-containing active drugs and peptides with thiocarbamate derivatives for the first time. This tri-component, onepot reaction can be performed smoothly under simple, gentle, and clean electrochemical conditions and is suitable for the functionalization of various Tyr-containing drug molecular derivatives and peptides.

关键词： tyrosine electrochemical radical coupling chemical modification peptides

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