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An asymmetric coplanar waveguide(ACPW)resonant antenna based on the composite right/left-handed transmission line

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Science China(Information Sciences) 2013年第12期56卷 139-147页

作者： wei shengjun FENG QuanYuan The Institute of Microelectronics Southwest Jiaotong University

An asymmetric coplanar waveguide(ACPW)resonant antenna based on a composite right/lefthanded transmission line(CRLH TL)is *** proposed antenna consists of an asymmetric coplanar waveguide feeding line and mushroom unit *** on the fundamental structure,an improvement on the antenna is *** novel structures including a strip-shaped extended ground plane and a rectangular extended ground plane are *** antenna with the strip-shaped extended ground plane exhibits bandwidth enhancement *** operating bandwidths with 10 dB return loss over 210MHz(1.57–1.78 GHz)is *** fractional bandwidth is enhanced from 0.31%to 12.5%,an improvement factor of approximately ***,the antenna with the rectangular extended ground plane presents broadband *** measured results,the impedance bandwidth over 3.19 GHz(2.65–5.84 GHz)was *** covers WiMAX 3.5/5.5 GHz and WLAN 5.2/5.8 GHz bands,and therefore could well apply to WiMAX/WLAN ***,the radiation patterns,peak gain and radiation efciency are also presented and discussed.

关键词： asymmetric coplanar waveguide(ACPW) composite right/left-handed transmission line(CRLH TL) bandwidth enhancement characteristic broadband feature

Dual-additives enable stable electrode-electrolyte interfaces for long life Li-SPAN batteries

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Chinese Chemical Letters 2024年第5期35卷 459-465页

作者： Zhenqiang Guo Huicong Yang Qian wei shengjun Xu Guangjian Hu Shuo Bai Feng Li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Biochemistry and Molecular Biology College of Life ScienceChina Medical UniversityShenyang 110122China Dalian National Laboratory for Clean Energy Dalian 116023China Shenyang King Power Technology Co. Ltd.Shenyang 110016China

Sulfurized polyacrylonitrile(SPAN)is proposed as a promising cathode material for lithium sulfur ***,the continuous side reactions at the electrolyte-electrode interfaces as well as the slow redox kinetics of SPAN cathode deteriorate the electrochemical *** this study,an electrolyte with dual-additives comprising 2-fluoropyridine(2-FP)and lithium difluorobis(oxalato)phosphate(LiDFBOP)was used to improve the performance of Li||SPAN cells.2-FP has a lower lowest occupied molecular orbital energy than that of the solvents in the electrolyte,leading to its prior reduction.A LiF-rich film can be formed on the electrode,effectively improving the stability of the electrolyte-electrode interfaces and prolonging the ***,LiDFBOP could form an electrolyte-electrode interface film containing a large amount of Li_(x)PO_(y)F_(z) species,compensating for the kinetic deterioration caused by the lower ionic conductive of LiF formed at the electrolyte-electrode ***,an electrode-interface film with good chemical stability and high Li^(+) transport was established by LiF and Li_(x)PO_(y)F_(z)-rich *** Li||SPAN cell with the electrolyte containing dual-additives demonstrates an excellent capacity retention of 97.5%after 200 cycles at 1.0 C,25℃,comparing to 56.2%capacity retention without ***,the rate capacities of cells with dual-additives can reach 1128.1 mAh/g at 5 C,comparing to only 813.5 mAh/g using electrolyte without *** results shown that the dual-additives in electrolyte provide a promising strategy for practical application of lithium sulfur batteries with SPAN cathodes.

关键词： Sulfurized polyacrylonitrile Lithium metal Interface film 2-Fluoropyridine Difluorobis(oxalato)phosphate

Cauliflower-like Ni_(3)S_(2) foam for ultrastable oxygen evolution electrocatalysis in alkaline seawater

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Nano Research 2024年第8期17卷 6820-6825页

作者： Qiuying Dai Xun He Yongchao Yao Kai Dong Xuwei Liu Xiankun Guo Jie Chen Xiaoya Fan Dongdong Zheng Yongsong Luo shengjun Sun Luming Li wei Chu Asmaa Farouk Mohamed SHamdy Xuping Sun Bo Tang Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJinan 250014China Institute for Advanced Study Chengdu UniversityChengdu 610106China Department of Chemistry College of ScienceKing Khalid UniversityP.O.Box 900461413 AbhaSaudi Arabia Center for High Altitude Medicine West China HospitalSichuan UniversityChengdu 610041China Laoshan Laboratory Qingdao 266237China

It is of great importance to design and develop electrocatalysts that are both long-lasting and efficient for seawater ***,a three-dimensional porous cauliflower-like Ni_(3)S_(2) foam on Ni foam(Ni_(3)S_(2) foam/NF)is proposed as a high-performance electrocatalyst for the oxygen evolution reaction in alkaline *** as-synthesis Ni_(3)S_(2) foam/NF achieves exceptional efficacy,achieving a current density of 100 mA·cm^(−2)at mere overpotential of 369 ***,its electrocatalytic stability extends up to 1000 h at 500 mA·cm^(−2).

关键词： Ni_(3)S_(2)foam oxygen evolution reaction seawater electrolysis electrocatalyst

高密度聚乙烯(HDPE)近海养殖网箱框架抗弯刚度分析

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渔业现代化 2022年第1期49卷 38-43页

作者：魏盛军福建省水产研究所福建省海洋生物增养殖与高值化利用重点实验室福建厦门361013

为研究高密度聚乙烯(HDPE)近海养殖网箱(俗称塑胶渔排)框架易变形的原因,从而找到提高改进的方法,解决易变形问题。本研究分析了影响网箱框架抗弯刚度关键要素,即框架截面、框架材料弹性模量和框架下方捆绑浮球跨距,并与传统海水养殖网... 详细信息

为研究高密度聚乙烯(HDPE)近海养殖网箱(俗称塑胶渔排)框架易变形的原因,从而找到提高改进的方法,解决易变形问题。本研究分析了影响网箱框架抗弯刚度关键要素,即框架截面、框架材料弹性模量和框架下方捆绑浮球跨距,并与传统海水养殖网箱进行比较。结果显示:HDPE近海养殖网箱框架边与传统养殖网箱的木质框架边的截面惯性矩差异性很小,截面结构几何性能相近;HDPE近海养殖网箱与传统养殖网箱木质框架边下方捆绑浮球跨距基本一致,不是导致刚性差异的主要因素;影响两者刚性差异的主要原因是材料性能,HDPE的弹性模量约为传统养殖网箱框架材料铁杉木的8.18%;研究表明:与传统养殖网箱相比,HDPE近海养殖网箱刚度有所不足,容易对安全生产造成影响;生产应用中需要适当提高HDPE近海养殖网箱的刚度,如通过优化框架结构、对HDPE进行改性,提升其弹性模量、增加辅助刚性设施等方式达到提升刚性等,以满足安全要求。

关键词：塑胶网箱框架抗弯刚度网箱养殖海水网箱

Surface-derived phosphate layer on NiFe-layered double hydroxide realizes stable seawater oxidation at the current density of 1 A·cm^(−2)

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Nano Research 2024年第7期17卷 5786-5794页

作者： Chaoxin Yang Zhengwei Cai Jie Liang Kai Dong Zixiao Li Hang Sun shengjun Sun Dongdong Zheng Hui Zhang Yongsong Luo Yongchao Yao Yan Wang Yuchun Ren Qian Liu Luming Li wei Chu Xuping Sun Bo Tang College of Chemistry Chemical Engineering and Materials ScienceShandong Normal UniversityJinan 250014China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Department of Science and Environmental Studies Faculty of Liberal Arts and Social Sciencethe Education University of Hong KongHong Kong 999077China Institute for Advanced Study Chengdu UniversityChengdu 610106China Laoshan Laboratory Qingdao 266237China

Seawater electrolysis,especially in coastlines,is widely considered as a sustainable way of making clean and high-purity H2 from renewable energy;however,the practical viability is challenged severely by the limited anode durability resulting from side reactions of chlorine ***,we report an effective Cl^(−) blocking barrier of NiFe-layer double hydroxide(NiFe-LDH)to harmful chlorine chemistry during alkaline seawater oxidation(ASO),a pre-formed surface-derived NiFe-phosphate(Pi)***,the PO_(4)^(3−)-enriched outer-layer is capable of physically and electrostatically inhibiting Cl−adsorption,which protects active Ni^(3+)sites during *** NiFe-LDH with the NiFe-Pi outer-layer(NiFe-LDH@NiFe-Pi)exhibits higher current densities(j)and lower overpotentials to afford 1 A·cm^(−2)(η1000 of 370 mV versusη1000 of 420 mV)than the NiFe-LDH in 1 M KOH+***,the NiFe-LDH@NiFe-Pi also demonstrates longer-term electrochemical durability than NiFe-LDH,attaining 100-h duration at the j of 1 A·cm^(−2).Additionally,the importance of surface-derived PO_(4)^(3−)-enriched outer-layer in protecting the active centers,γ-NiOOH,is explained by ex situ characterizations and in situ electrochemical spectroscopic studies.

关键词： seawater oxidation phosphate outer-layer layered double hydroxide electrostatic repulsion in situ Raman

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智慧小区的安防管理系统设计

集成电路应用 2022年第10期39卷 140-141页

作者：魏胜君中山职业技术学院广东528400

阐述智慧安防小区管理系统的设计,将手机终端作为基本载体,灵活使用自助录入平台,在建立报警和警戒系统时,能够确保系统设置的完善性,探讨管控系统架构优化和完善。

关键词：智慧城市小区安防警戒系统

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一种具有补光性能的人脸识别装置设计

电子技术（上海） 2022年第2期51卷 172-173页

作者：魏胜君中山职业技术学院广东528471

阐述在复杂的光线条件下的面部识别算法,提供了一个面部识别装置,它可以在不可见的环境中提供照明,包括面部识别装置、控制至少两种不同类型的补光亮度。

关键词：人脸识别人脸库光照

新能源汽车燃料电池用质子交换膜的制备及性能

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合成树脂及塑料 2021年第4期38卷 11-14,25页

作者：魏胜君中山职业技术学院机电工程学院广东中山528400

制备了一系列降冰片烯共聚物,经过接枝和交联,得到了交联度和咪唑磷酸盐基团含量不同的交联型降冰片烯共聚物薄膜,并研究了其性能。随着交联度的提升,薄膜的拉伸强度由24.4 MPa提升至36.6 MPa,断裂伸长率有所降低;薄膜具有优异的热稳定... 详细信息

制备了一系列降冰片烯共聚物,经过接枝和交联,得到了交联度和咪唑磷酸盐基团含量不同的交联型降冰片烯共聚物薄膜,并研究了其性能。随着交联度的提升,薄膜的拉伸强度由24.4 MPa提升至36.6 MPa,断裂伸长率有所降低;薄膜具有优异的热稳定性,初始分解温度均达到300℃以上;高交联度薄膜的初始分解温度高达405℃。咪唑磷酸盐基团是主要的质子传导基团,也是造成甲醇透过的基团,因此,高交联度薄膜具有较高的质子传导率和甲醇透过率。降冰片烯与5-降冰片烯-2-亚乙基乙酸酯用量均为10.0 mmol时,相应薄膜的质子传导率和甲醇透过率分别为0.0043 S/cm^(2),3.74×10^(-6)cm^(-1)·s,与Nafion115薄膜相当。

关键词：降冰片烯共聚物交联质子交换膜燃料电池

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高速注采储气库井套管螺纹密封性研究

西南石油大学学报（自然科学版） 2024年第3期46卷 170-178页

作者：宋巍周岩吴艳杨燕叶盛军中国石油冀东油田公司采油工艺研究院河北唐山063000

套管螺纹密封性是影响周期性高速注采作业的储库气井安全性的关键因素,因此保证储气库井的密封性完整极其重要。需要重点研究储气库井注采过程中对其套管柱密封性的影响,特别是循环注采过程中产生的交变载荷对储气库套管柱特殊螺纹接头... 详细信息

套管螺纹密封性是影响周期性高速注采作业的储库气井安全性的关键因素,因此保证储气库井的密封性完整极其重要。需要重点研究储气库井注采过程中对其套管柱密封性的影响,特别是循环注采过程中产生的交变载荷对储气库套管柱特殊螺纹接头密封结构性能的影响。基于有限元法理论,针对中国北部某储气库井所选用的特殊螺纹接头,结合储气库井实际工况和现场数据,建立套管接头螺纹有限元计算模型,研究了循环注采条件下,温度、注采压力、轴向载荷及点蚀对储气库套管螺纹密封状态的影响。结果表明,温度对套管螺纹接头的结构完整性和密封完整性影响较小,注采压力、轴向载荷和点蚀对其影响较大,需控制在一个较低值。研究可为储气库井套管柱密封失效判定及其套管柱设计提供参考。

关键词：储气库井特殊螺纹接头套管密封性高速注采交变载荷

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