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Reconfigurable paper-based metamaterial antenna: Structural transition from 2D to 3D

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Science China Technological Sciences 2024年第9期67卷 2811-2816页

作者： PANG YaChen GAO Song YAO HuiMing WANG LiWei CAO JinQing ZHANG ZiDong xu jianchun GUO YunSheng BI Ke State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and Telecommunications Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) Shandong University School of Electronic Information Engineering Inner Mongolia University

Paper-based electronics offer a simple and cost-effective means to fabricate reconfigurable devices. In response to the problem of fixed shape and single function of most antennas, which limits their applications, a reconfigurable paper-based metamaterial antenna with 2D and 3D forms is presented for tunable operating frequency. The proposed antenna consists of two square split resonant rings fed by a coplanar waveguide. The working frequency of the 2D antenna is adjusted by the length, width, and opening size of the internal open resonant ring. While the folding angle of the antenna turns from 0° to 90°, the operating frequency of the paper-based metamaterial antenna changes from 2.759 to 4.223 GHz. In terms of 3D form, an additional resonant peak is generated by bending the paper-based metamaterial antenna, thus further realizing dual-band antenna *** a simple process flow, a series of proposed antennas are fabricated and evaluated. The simulated and measured results both demonstrate that the proposed antenna has a good performance in turning the working band. The environment-friendly nature and pliability of paper, as well as simple fabrication procedures, make paper-based metamaterial promising candidates for future green electronics.

关键词： paper-based reconfigurable antennas metamaterial

万古霉素诱导人肾小管上皮细胞损伤及其Smad4表达的研究

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现代药物与临床 2024年第1期39卷 8-13页

作者：高瑞肖晓琳许建春宋玮天津市第五中心医院药剂科天津300450 天津市第五中心医院中心实验室天津300450

目的研究万古霉素诱导人肾小管上皮细胞(HK-2)损伤及其Smad同源物4(Smad4)表达,并探讨其潜在的作用机制。方法使用不同终浓度(0、1、2、3、4、5 mmol/L)的万古霉素溶液作用于HK-2细胞24 h,显微镜下观察万古霉素对细胞形态的影响;蛋白... 详细信息

目的研究万古霉素诱导人肾小管上皮细胞(HK-2)损伤及其Smad同源物4(Smad4)表达,并探讨其潜在的作用机制。方法使用不同终浓度(0、1、2、3、4、5 mmol/L)的万古霉素溶液作用于HK-2细胞24 h,显微镜下观察万古霉素对细胞形态的影响;蛋白质免疫印迹法检测Smad4、B淋巴细胞瘤-2(Bcl-2)相关X蛋白(Bax)、Bcl-2的蛋白水平;TUNEL法检测HK-2细胞凋亡情况;CCK8法检测HK-2细胞活力来研究万古霉素对肾脏的毒性作用。构建Smad4过表达质粒,通过CCK8法和TUNEL实验检测Smad4过表达对万古霉素诱导的HK-2细胞损伤的影响。结果与对照组比较,随着万古霉素浓度升高,HK-2细胞逐渐变形,数量逐渐减少;细胞活力显著降低,凋亡率显著增加(P<0.05、0.01)。与对照组比较,促凋亡蛋白Bax表达显著增高,而抗凋亡蛋白Smad4、Bcl-2表达则显著降低(P<0.05、0.01、0.001)。过表达Smad4后,使万古霉素诱导的HK-2的细胞活力显著增加,凋亡率显著降低(P<0.05、0.001)。结论万古霉素能够诱导人肾小管上皮细胞损伤,其作用机制可能与调控Smad4的蛋白降解密切相关。

关键词：万古霉素人肾近曲小管上皮细胞肾损伤 Smad同源物4 B淋巴细胞瘤-2 B淋巴细胞瘤-2相关X蛋白

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基于层间耦合的宽带毫米波超表面天线

电子元件与材料 2024年第1期43卷 110-114页

作者：李晗逯景桐张帅许建春毕科北京邮电大学理学院北京100876 北京航天众信科技有限公司北京100195

通信技术快速发展,对高速、大容量通信需求迫切。然而,传统频谱资源受限,难以满足需求,毫米波天线备受瞩目。本研究旨在改善传统微带贴片天线的带宽和增益问题。通过加载超表面结构和加强层间耦合的方法,设计了24~50 GHz宽带毫米波超表... 详细信息

通信技术快速发展,对高速、大容量通信需求迫切。然而,传统频谱资源受限,难以满足需求,毫米波天线备受瞩目。本研究旨在改善传统微带贴片天线的带宽和增益问题。通过加载超表面结构和加强层间耦合的方法,设计了24~50 GHz宽带毫米波超表面天线。该天线采用层压方式将超表面加载在介质层中,通过仿真分析了超表面参数对天线带宽的影响,从而确定最佳天线结构尺寸,并进行了天线的制作和性能测试。仿真和实测结果表明,该天线能够实现24~50 GHz的宽带,相比传统贴片天线,其带宽增加了52.23%,并具有良好的辐射特性和增益性能。该宽带毫米波超表面天线在宽频段通信、5G通信等领域具备广阔的应用前景。

关键词：毫米波天线超表面微带天线宽带设计

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基于电阻膜的宽带超材料吸波体设计

电子元件与材料 2024年第2期43卷 176-181页

作者：杨佳蓬逯景桐张帅许建春毕科北京邮电大学理学院北京100876 北京航天众信科技有限公司北京100195

基于吸波材料有效吸收和耗散电磁波能量的特性,研究人员实现了对电磁波的精确控制与隔离,这对电磁波的调控起到至关重要的作用。为实现宽带平稳吸收电磁波,提出了一种基于电阻膜的宽频带超材料吸波体,该结构由三层构成,顶层采用周期排... 详细信息

基于吸波材料有效吸收和耗散电磁波能量的特性,研究人员实现了对电磁波的精确控制与隔离,这对电磁波的调控起到至关重要的作用。为实现宽带平稳吸收电磁波,提出了一种基于电阻膜的宽频带超材料吸波体,该结构由三层构成,顶层采用周期排布的电阻膜结构,中间层采用FR-4介质基板,底层采用金属背板。电阻膜主要由导电油墨构成,其作用是吸收电磁波能量后将其转化为热能进行耗散。仿真测试表明,所设计的吸波体在14.2~25.3 GHz频率范围内达到了90%以上的吸收率,平均吸收率高达98.23%,且具备偏振不敏感特性。为了验证设计的可行性,通过控制丝网印刷的参数和条件成功制备了吸波体样品,实际测量值与全波模拟结果展现了较好的一致性,为宽带吸波体的设计提供了参考依据。

关键词：电阻膜超材料宽带吸波体

Synthesis of carbon dots with predictable photoluminescence by the aid of machine learning

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Nano Research 2024年第3期17卷 1984-1989页

作者： Chenyu Xing Gaoyu Chen Xia Zhu Jiakun An jianchun Bao xuan Wang Xiuqing Zhou Xiuli Du Xiangxing xu Jiangsu Key Laboratory of Biofunctional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China School of Mathematical Sciences Nanjing Normal UniversityNanjing 210023China State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

Carbon dots(CDs)have wide application potentials in optoelectronic devices,biology,medicine,chemical sensors,and quantum techniques due to their excellent fluorescent ***,synthesis of CDs with controllable spectrum is challenging because of the diversity of the CD components and *** this report,machine learning(ML)algorithms were applied to help the synthesis of CDs with predictable photoluminescence(PL)under the excitation wavelengths of 365 and 532 *** combination of precursors was used as the *** PL peaks of the strongest intensity(λ_(s))and the longest wavelength(λ_(l))were used as target *** six investigated ML models,the random forest(RF)model showed outstanding)performance in the prediction of the PL peaks.

关键词： carbon dots(CDs) synthesis photoluminescence(PL) machine learning(ML) PL prediction

Electronic structure and spin state regulation of vanadium nitride via a sulfur doping strategy toward flexible zinc-air batteries

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Journal of Energy Chemistry 2024年第2期89卷 239-249,I0007页

作者： Daijie Deng Honghui Zhang jianchun Wu Xing Tang Min Ling Sihua Dong Li xu Henan Li Huaming Li Institute for Energy Research Institute of Quantum and Sustainable TechnologySchool of Chemistry and Chemical EngineeringSchool of Materials Science and EngineeringJiangsu Province and Education Ministry Co-Sponsored Synergistic Innovation Center of Modern Agricultural EquipmentJiangsu UniversityZhenjiang 212013JiangsuChina Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province Nanjing 210023JiangsuChina Zhenjiang Kangyuan Electrical Appliance Co. Ltd.Zhenjiang 212013JiangsuChina College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310027ZhejiangChina YTO Group Corporation Dongfanghong(Henan)Agricultural Service Technology Co. Ltd.Luoyang 471033HenanChina

Owing to the distinctive structural characteristics,vanadium nitride(VN)is highly regarded as a catalyst for oxygen reduction reaction(ORR)in zinc-air batteries(ZABs).However,VN exhibits limited intrinsic ORR activity due to the weak adsorption ability to O-containing ***,the S-doped VN anchored on N,S-doped multi-dimensional carbon(S-VN/Co/NS-MC)was constructed using the solvothermal and in-situ doping *** sulfur atoms into VN species alters the electron spin state of vanadium in the S-VN/Co/NS-MC for regulating the adsorption energy of vanadium sites to oxygen *** introduced sulfur atoms polarize the V 3d_(z)^(2) electrons,shifting spin-down electrons closer to the Fermi level in the S-VN/Co/***,the introduction of sulfur atoms into VN species enhances the adsorption energy of vanadium sites for oxygen ****OOH dissociation transitions from being unspontaneous on the VN surface to a spontaneous state on the S-doped VN ***,the ORR barrier on the S-VN/Co/NS-MC surface is *** S-VN/Co/NS-MC demonstrates a higher half-wave potential and limiting current density compared to the VN/Co/*** S-VN/Co/NS-MC-based liquid ZABs display a power density of 195.7 m W cm^(-2),a specific capacity of 815.7 m A h g^(-1),and a cycling stability exceeding 250 *** S-VN/Co/NS-MC-based flexible ZABs are successfully employed to charge both a smart watch and a mobile *** approach holds promise for advancing the commercial utilization of VN-based catalysts in ZABs.

关键词： S-doped VN Electronic structures Spin state regulation Oxygen reduction reaction Zinc-air batteries

Microfluidic synthesis of hollow CsPbBr3 perovskite nanocrystals through the nanoscale Kirkendall effect

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Nano Research 2024年第9期17卷 8487-8494页

作者： Yue Chen Xiaoyu Zhang Jinzhou Jiang Gaoyu Chen Kunhong Zhou Xinwen Zhang Fajing Li Caojin Yuan jianchun Bao Xiangxing xu Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China Key Laboratory for Organic Electronics and Information Displays Institute of Advanced Materials(IAM)Nanjing University of Posts and TelecommunicationsNanjing 210023China Frontiers Science Center for Flexible Electronics Institute of Flexible Electronics(IFE)Northwestern Polytechnical UniversityXi’an 710072China Jiangsu Key Laboratory for Opto-Electronic Technology School of Physics and TechnologyNanjing Normal UniversityNanjing 210023China State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

All inorganic metal halide perovskite nanocrystals(NCs)have attracted much attention for their outstanding optoelectronic properties,which can be tuned by the composition,surface,size and morphology in ***,we report the microfluidic synthesis of hollow CsPbBr_(3)perovskite NCs through the nanoscale Kirkendall *** formation mechanism of the hollow structure(Kirkendall void)controlled by the temperature,flow rate,ratios of precursors and ligands was *** with the solid CsPbBr_(3)NCs of the same size,the hollow CsPbBr_(3)NCs exhibit blue shifts in ultraviolet-visible(UV-vis)absorption and photoluminescence(PL)spectra,and remarkably longer PL average lifetime(~98.2 ns).Quantum confinement effect,inner surface induced additional trap states and lattice strain of the hollow CsPbBr_(3)NCs were discussed in understanding their unique optoelectronic *** hollow CsPbBr_(3)NC based photodetector exhibits an outstanding negative photoconductivity(NPC)detectivity of 8.9×10^(12)*** also show potentials in perovskite NC based photovoltaic and light emitting diodes(LEDs).

关键词： perovskite nanocrystals hollow nanocrystals nanoscale Kirkendall effect microfluidic synthesis

Study of Residual Basin and Tectonolayering Based on Airborne Gravity and Magnetic Data

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Acta Geologica Sinica(English Edition) 2013年第4期87卷 1137-1153页

作者： LI Wenyong ZHOU Jianxin XIONG Shengqing LIU Yanxu xu jianchun China Aero Geophysical Survey and Remote Sensing Center for Land and Resources

This paper takes the South Yellow Sea as an example to show a new method for comprehensive geological-geophysical research such as residual basin and tectonolayering using airborne gravity and magnetic data in China. Based on airborne gravity and magnetic data, by measuring and analyzing stratigraphic density and susceptibility, the depths to the pre-Sinian magnetic basement top, the pre-Jurassic top and the Cenozoic bottom, are obtained by forward and inverse methods constrained by seismic and drilling data; and furthermore, the residual thicknesses of the Sinian-Triassic, the Jurassic-Cretaceous and the Cenozoic are calculated. Based on airborne gravity and magnetic anomalies, the faults in the pre-Sinian magnetic basement, the Jurassic-Cretaceous and the Cenozoic are respectively interpreted by the qualitative and quantitative methods. On the basis of the above study, and combining regional important tectonic events, four tectonolayers are divided in the vertical succession in South Yellow Sea, namely the pre-Sinian magnetic basement, the Sinian-Triassic, the Jurassic-Cretaceous and the Cenozoic. The result shows that there are thick Cenozoic and Jurassic-Cretaceous strata and thin residual Sinian-Triassic strata in the Suzhong-Huangnan depression area, but there are thin or only sporadic Mesozoic-Cenozoic terrestrial strata and thick Sinian-Triassic marine strata reserved in Subei-Huangzhong uplift area and Sunan-Wunansha uplift area. The four tectonolayers are very different in structures as well as distributions in plane.

关键词： airborne gravity and magnetics comprehensive interpretation residual basin,tectonolayering South Yellow Sea

Superimposed versus residual basin:The North Yellow Sea Basin

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Geoscience Frontiers 2012年第1期3卷 33-39页

作者： Wenyong Li Wenfen Lu Yanxu Liu jianchun xu China Aero Geophysical Survey and Remote Sensing Center for Land and Resources Beijing 100083China

The North Yellow Sea Basin is a Mesozoic and Cenozoic basin. Based on basin-margin facies, sedimentary thinning, size and shape of the basin and vitrinite reflectance, North Yellow Sea Basin is not a residual basin. Analysis of the development of the basin＇s three structural layers, self-contained petroleum systems, boundary fault activity, migration of the Mesozoic--Cenozoic sedimentation centers, different basin structures formed during different periods, and superposition of a two-stage extended basin and one-stage depression basin, the North Yellow Sea Basin is recognized as a superimposed basin.

关键词： Superimposed basin Residual basin Identification method Basinal structures Basin superposition North Yellow Sea Basin