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Development of a Front End Array for Broadband Phased Array Receiver

Research in Astronomy and Astrophysics 2024年第4期24卷 60-70页

作者： Kai Wang liang Cao Jun Ma Xue-Feng duan Hao Yan Mao-Zheng Chen Yun-wei Ning Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 8300lChina University of the Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

The receiver is a signal receiving device placed at the focus of the *** order to improve the observation efficiency,the concept of phased array receiver has been proposed in recent years,which places a small phased array at the focal plane of the reflector,and flexible pattern and beam scanning functions can be achieved through a beamforming *** combined with the element multiplexing,all beams within the entire field of view can be observed simultaneously to achieve continuous sky *** article focuses on the front-end array of phased array receiver at 0.7-1.8 GHz for QiTai Telescope,and designs a Vivaldi antenna array of PCB structure with dual line *** polarization antenna is designed to arrange in a rectangle manner by 11×*** on the simulation results of the focal field,32,18,and eight elements were selected to form one beam at 0.7,1.25,and1.8 *** analog beamforming network was constructed,and the measured gains of axial beam under uniform weighting were 19.32,13.72,and 15.22 *** the beam scanning method of reflector antenna,the pattern test of different position element sets required for PAF beam scanning was carried out under independent *** pattern optimization at 1.25 GHz was carried out by weighting method of conjugate field *** with uniform weighting,the gain,sidelobe level,and main beam direction under conjugate field matching have been *** the above test and simulation results are slightly different,which is related to the passive array and laboratory testing condition,the relevant work has accumulated experience in the development of the front-end array for the phased array receiver,and has good guiding significance for future performance verification after the array is installed on the telescope.

关键词： telescopes instrumentation:detectors techniques:radar astronomy

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Highly sensitive nanozyme strip:An effective tool for forensic material evidence identification

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Nano Research 2024年第3期17卷 1785-1791页

作者： Juanji Hong Zhanjun Guo Dihan duan Yi Zhang Xin Chen Yongjiu li Zheng Tu Lei Feng Lei Chen Xiyun Yan lizeng Gao Minmin liang Demin duan Experimental Center of Advanced Materials School of Materials Science&EngineeringBeijing Institute of TechnologyBeijing 100081China College of Bioscience and Biotechnology Shenyang Agricultural UniversityShenyang 110866China Chongqing kangjuquanhong biology science and technology Co. ltdChongqing 400026China Key Laboratory of Forensic Genetics Institute of Forensic ScienceMinistry of Public SecurityBeijing 100038China CAS Engineering Laboratory for Nanozyme Key Laboratory of BiomacromoleculesInstitute of BiophysicsChinese Academic of ScienceBeijing 100101China

During criminal case investigations,blood evidence tracing is critical for criminal ***,the blood stains are often cleaned or covered up after the crime,resulting in trace residue and difficult ***,a highly sensitive and specific method for the rapid detection of human blood stains remains *** solve this problem,we established a nanozyme-based strip for rapid detection of blood evidence with high sensitivity and *** construct reliable nanozyme strips,we synthesized CoFe_(2)O_(4) nanozymes with high peroxidase-like activity by scaling up to gram level,which can be supplied for six million tests,and conjugated antibody as a detection probe in nanozyme *** developed CoFe_(2)O_(4) nanozyme strip can detect human hemoglobin(HGB)at a concentration as low as 1 ng/mL,which is 100 times lower than the commercially available colloidal gold strips(100 ng/mL).Moreover,this CoFe_(2)O_(4) nanozyme strip showed high generality on 12 substrates and high specificity to human HGB among 13 animal blood ***,we applied the developed CoFe_(2)O_(4) nanozyme strip to successfully detect blood stains in three real cases,where the current commercial colloidal gold strip failed to *** results suggest that the CoFe_(2)O_(4) nanozyme strip can be used as an effective on-scene detection method for human blood stains,and can further be used as a long-term preserved material evidence for traceability inquiry.

关键词： CoFe_(2)O_(4)nanozyme nanozyme strip peroxidase-like activity human hemoglobin blood evidence

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Design and preparation of highly crystalline K-intercalated W@PCN:an efficient material for aniline elimination

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Rare Metals 2024年第3期43卷 1337-1342页

作者： Hao-Fei li Kai-Wen Yu Xiao-Bi Jing Lei duan Yi-Yang Zhang School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou225002China School of Mechanical Engineering Yangzhou UniversityYangzhou225127China School of Material Science and Engineering Huazhong University of Science and TechnologyWuhan430071China School of Chemical Engineering and Materials Changzhou Institute of TechnologyChangzhou213032China Department of Basic Courses Army Engineering University of PLANanjing211101China

In this paper,we designed and prepared the polymeric carbon nitride-supported tungsten(W@PCN)*** were employed as the catalysts for photocatalytic oxidation of aniline in *** the process,H_(2)O_(2)was initially generated via the PCN-catalyzed *** by supported tungsten,aniline was oxidized by the in situ generated H_(2)O_(2)to obtain less toxicpoly aniline.

关键词： materials aniline crystalline

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A Review on Engineering Transition Metal Compound Catalysts to Accelerate the Redox Kinetics of Sulfur Cathodes for lithium–Sulfur Batteries

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Nano-Micro Letters 2024年第5期16卷 300-332页

作者： liping Chen Guiqiang Cao Yong li Guannan Zu Ruixian duan Yang Bai Kaiyu Xue Yonghong Fu Yunhua Xu Juan Wang Xifei li Shaanxi Key Laboratory of Nanomaterials and Nanotechnology Xi’an University of Architecture and TechnologyXi’an 710055People’s Republic of China Institute of Advanced Electrochemical Energy and School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048People’s Republic of China Yulin University Yulin 719000People’s Republic of China School of Materials Science and Engineering Fuzhou UniversityFuzhou 350108People’s Republic of China

Engineering transition metal compounds(TMCs)catalysts with excellent adsorption-catalytic ability has been one of the most effec-tive strategies to accelerate the redox kinetics of sulfur ***,this review focuses on engineering TMCs catalysts by cation doping/anion doping/dual doping,bimetallic/bi-anionic TMCs,and TMCs-based heterostructure *** is obvious that introducing cations/anions to TMCs or constructing heterostructure can boost adsorption-catalytic capacity by regulating the electronic structure including energy band,d/p-band center,electron filling,and valence ***,the elec-tronic structure of doped/dual-ionic TMCs are adjusted by inducing ions with different electronegativity,electron filling,and ion radius,resulting in electron redistribution,bonds reconstruction,induced vacancies due to the electronic interaction and changed crystal structure such as lat-tice spacing and lattice *** from the aforementioned two strategies,heterostructures are constructed by two types of TMCs with different Fermi energy levels,which causes built-in electric field and electrons transfer through the interface,and induces electron redistribution and arranged local atoms to regulate the electronic ***,the lacking studies of the three strategies to comprehensively regulate electronic structure for improving catalytic performance are pointed *** is believed that this review can guide the design of advanced TMCs catalysts for boosting redox of lithium sulfur batteries.

关键词： lithium–sulfur battery Redox kinetic Transition metal compounds catalyst Multiple metals/anions

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Comprehensive evaluation of an ionic liquid based deep purification process for NH_(3)-containing industrial gas

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Journal of Environmental Sciences 2024年第2期136卷 698-708页

作者： Guoxiong Zhan Fei Cao Jianjun Chen Zhen Chen Yuanmeng duan Fei Chang Shaojuan Zeng Yinge Bai Zengxi li Xiangping Zhang Junhua li State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Sino-Danish College University of Chinese Academy of SciencesBeijing 100049China Institute of Process Engineering Chinese Academy of SciencesBeijing 100190China College of Chemical and Engineering University of Chinese Academy of SciencesBeijing 100049China

Ammonia(NH_(3))emission has caused serious environment issues and aroused worldwide *** emerging ionic liquid(IL)provides a greener way to efficiently capture NH_(3).This paper provides rigorous process simulation,optimization and assessment for a novel NH_(3)deep purification process using *** process was designed and investigated by simulation and optimization using ionic liquid[C_(4)im][NTF_(2)]as *** objective functions,total purification cost(TPC),total process CO_(2)emission(TPCOE)and thermal efficiency(ηeff)were employed to optimize the absorption *** simulation and optimization results indicate that at same purification standard and recovery rate,the novel process can achieve lower cost and CO_(2)emission compared to benchmark *** process optimization,the optimal functions can achieve 0.02726$/Nm~3(TPC),311.27 kg CO_(2)/hr(TP-COE),and 52.21%(ηeff)for enhanced ***,compared with conventional process,novel process could decrease over$3 million of purification cost and 10000 tons of CO_(2)emission during the life *** results provide a novel strategy and guidance for deep purification of NH_(3)capture.

关键词： NH_(3) Capture Process Ionic liquid Process Simulation Process Optimization Deep purification

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The Negative Thermal Expansion Property of NdMnO_(3) Based on Pores Effect and Phase Transition

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 39-43页

作者：李玉成张扬 ZHANG Muqun duan Rong liU Xiteng Department of Avionics Engineering Aviation Maintenance NCO Academy of Air Force Engineering UniversityXinyang 464000China

A novel negative thermal expansion(NTE) material NdMnO_(3) was synthesized by solid-state method at 1 523 K. The crystal structure, phase transition, pores effect and negative expansion properties of NdMnO_(3) were investigated by variable temperature X-ray diffraction(XRD), scanning electron microscope(SEM) and variable temperature Raman spectra. The compound exhibits NTE properties in the orderly O' phase crystal structure. When the temperature is from 293 to 759 K, the ceramic NdMnO_(3) shows negative thermal expansion of-4.7×10^(-6)/K. As temperature increases, the ceramic NdMnO_(3) presents NTE property range from 759 to 1 007 K. The average linear expansion coefficient is-18.88×10^(-6)/K. The physical mechanism of NTE is discussed and clarified through experiments.

关键词： negative thermal expansion NdMnO_(3) pores effect phase transition

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Extremum seeking control for UAV close formation flight via improved pigeon-inspired optimization

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Science China(Technological Sciences) 2024年第2期67卷 435-448页

作者： YUAN GuangSong duan HaiBin State Key Laboratory of Virtual Reality Technology and Systems School of Automation Science and Electrical EngineeringBeihang University(BUAA)Beijing 100083China

This paper proposes a comprehensive design scheme for the extremum seeking control(ESC)of the unmanned aerial vehicle(UAV)close formation *** proposed design scheme combines a Newton-Raphson method with an extended Kalman filter(EKF)to dynamically estimate the optimal position of the following UAV relative to the leading *** reflect the wake vortex effects reliably,the drag coefficient induced by the wake vortex is considered as a performance ***,the performance function is parameterized by the first-order and second-order terms of its Taylor series *** the excellent performance of nonlinear estimation,the EKF is used to estimate the gradient and the Hessian matrix of the parameterized performance *** output feedback of the proposed scheme is determined by iterative calculation of the Newton-Raphson *** with the traditional ESC and the classic ESC,the proposed design scheme avoids the slow continuous time integration of the *** allows a faster convergence of relative position ***,the proposed method can provide a smoother command during the seeking process as the second-order term of the performance function is taken into *** convergence analysis of the proposed design scheme is accomplished by showing that the output feedback is a supermartingale *** improve estimation performance of the EKF,a improved pigeon-inspired optimization(IPIO)is proposed to automatically tune the noise covariance *** Carlo simulations for a three-UAV close formation show that the proposed design scheme is robust to the initial position of the following UAV.

关键词： unmanned aerial vehicle close formation extremum seeking control Newton-Raphson method improved pigeon-inspired optimization

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Manure substitution improves maize yield by promoting soil fertility and mediating the microbial community in lime concretion black soil

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Journal of Integrative Agriculture 2024年第2期23卷 698-710页

作者： Minghui Cao Yan duan Minghao li Caiguo Tang Wenjie Kan Jiangye li Huilan Zhang Wenling Zhong lifang Wu The Center for Ion Beam Bioengineering&Green Agriculture Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Zhongke Taihe Experimental Station Taihe 236626China Institute of Resources and Environment Jiangsu Academy of Agricultural SciencesNanjing 210014China

Synthetic nitrogen(N)fertilizer has made a great contribution to the improvement of soil fertility and productivity,but excessive application of synthetic N fertilizer may cause agroecosystem risks,such as soil acidification,groundwater contamination and biodiversity ***,organic substitution has received increasing attention for its ecologically and environmentally friendly and productivity ***,the linkages between manure substitution,crop yield and the underlying microbial mechanisms remain *** bridge this gap,a three-year field experiment was conducted with five fertilization regimes:i)Control,non-fertilization;CF,conventional synthetic fertilizer application;CF_(1/2)M_(1/2),1/2 N input via synthetic fertilizer and 1/2 N input via manure;CF_(1/4)M_(3/4),1/4 N input synthetic fertilizer and 3/4 N input via manure;M,manure *** fertilization treatments were designed to have equal N *** results showed that all manure substituted treatments achieved high soil fertility indexes(SFI)and productivities by increasing the soil organic carbon(SOC),total N(TN)and available phosphorus(AP)concentrations,and by altering the bacterial community diversity and composition compared with ***,AP,and the soil C:N ratio were mainly responsible for microbial community *** co-occurrence network revealed that SOC and AP had strong positive associations with Rhodospirillales and Burkholderiales,while TN and C:N ratio had positive and negative associations with Micromonosporaceae,*** specific taxa are implicated in soil macroelement *** Forest analysis predicted that both biotic(bacterial composition and Micromonosporaceae)and abiotic(AP,SOC,SFI,and TN)factors had significant effects on crop *** present work strengthens our understanding of the effects of manure substitution on crop yield and provides theoretical support for optimizing fertilization strategies.

关键词： fertilization manure substitution soil fertility maize yield bacterial community

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Super-high bed sintering for iron ores: inhomogeneous phenomena and its mechanism during mineralizing

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Journal of Iron and Steel Research International 2024年第8期31卷 1850-1860页

作者： Hui-bo liu liang-ping Xu Xi-duan Yang Zhong-lin Dong Qiang Zhong Guang-hui li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

The inhomogeneous sinter properties in super-high bed sintering have been reported in our previous *** inves-tigate the reasons for the inhomogeneous phenomena,detailed sampling and analysis of mixed material bed and sintered bed in super-high bed sintering plant were *** results indicated that the higher porosity and thinner dendrite of silico-ferrite of calcium and aluminum in the upper layer as well as dense structure and higher secondary hematite content in the lower layer led to the heterogeneities of mechanical strength and reduction properties exceeding 20%and 10%,*** the bed top downward,the basicity of mixed material decreased from 2.13 to 1.68 because the average particle size increased from 2.65 to 4.56 *** and fuels gathered in finer particles(-3 mm)of mixed material,and the-3 mm particles of mixed material generated more liquid phase than+3 mm *** heat input of super-high sintering bed was inhomogeneous due to the heat accumulation effect and unreasonable fuel *** inhomo-geneous sintering heat condition in sintering bed resulted in the different quantities and properties of liquid *** inhomogeneous quantities and properties of liquid phase that were influenced by inhomogeneous distribution of chemical composition,particle size,and heat input led to inhomogeneous mineralizing *** mineralizing condition is the key for homogeneous super-high bed sintering.

关键词： Iron ore Super-high bed sintering Mineralization Material segregation Heat accumulation

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Enhanced bifunctional oxygen electrochemical catalytic performance using La-doped CoFe_(2)O_(4)spinel supported by 3D-G for Zn-air batteries

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Journal of Energy Chemistry 2024年第7期94卷 778-788页

作者： Yinggang Sun Tingwei Zhang Peng Sun Jigang Wang Wenjie duan Yanqiong Zhuang likai Wang Zhongfang li School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255049ShandongChina

The preparation of bifunctional catalysts for oxygen reduction(ORR)and oxygen evolution(OER)is crucial for Zn-air ***,we report a La doped CoFe_(2)O_(4) spinel catalyst supported on threedimensional graphene(3D-G),where La can facilitate electron transfer from Co to Fe,leading to increased electron cloud density in Fe and improved catalytic *** redshift of the G peak in the Raman spectra indicates the interaction between theπbond of 3D-G and d orbitals in La_(0.2)CoFe_(1.8)O_(4).La_(0.2)CoFe_(1.8)/3D-G exhibits superior ORR performance(E_(1/2)=0.86 V ***)and OER performance(E_(j=10)=1.55 V ***)to CoFe_(2)O_(4)/3D-G(E_(1/2)=0.831 V ***,E_(j=10)=1.603 V ***).Furthermore,it demonstrates excellent bifunctional oxygen catalytic performance while maintaining high power density and stability in liquid zinc-air batteries(ZABs)and flexible ZABs(F-ZABs).This work presents a viable strategy for utilizing rare earth element doped spinels to enhance oxygen catalyst and ZABs performance.

关键词： Zn-air batteries Electrocatalysts La_(0.2)CoFe_(1.8)/3D-G Electron pump Bifunctional oxygen catalytic performance

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