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A 27 GHz,simple 2-bit 1×8 phased array

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Journal of Electronic Science and Technology 2024年第3期22卷 26-34页

作者： Jun-Xian Liu yun-Ying Man Hao Yang peng Yang School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

This study demonstrates a simple 2-bit phased array operating at 27 GHz that supports one-dimensional beam scanning with left-handed circular polarization(LHCP).The antenna is constructed using a compact four-layer printed circuit board(PCB)structure,consisting of a 90°phase shifter layer with microstrip structures,a ground(GND)layer,a direct current(DC)control layer,and a circularly polarized annular radiation patch layer with 1-bit phase *** on the proposed unit structure,a 1×8 array with half-wavelength inter-element spacing was designed and *** results show that the array achieves a peak gain of 10.23 dBi and is capable of beam scanning within±50°.

关键词： 27 GHz 2-bit P-i-n diodes Phased array Reconfigurable antennas

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

Farnesoid X receptor regulators from natural products and their biological function

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Journal of Traditional Chinese Medicine 2023年第3期43卷 618-626页

作者： peng Wan NI Hengfan GUO Dale DENG yun DAI Manyun Institute of Rare Diseases West China HospitalSichuan UniversityChengdu 610065China Department of Pharmacy West China HospitalSichuan UniversityChengdu 610041China School of Pharmacy Chengdu University of Traditional Chinese MedicineState Key Laboratory of Southwestern Chinese Medicine ResourcesChengdu 611137China School of Medicine Ningbo UniversityNingbo 315000China

Metabolic syndrome(Met S)has been a growing public health concern worldwide without specific *** summarizing the chemical structure type and effect mechanisms of natural products targeted on farnesoid X receptor(FXR),to provide the research basis for exploring the treatment of Met *** following databases were searched for natural products which targeting FXR:Pub Med,Embase,the Cochrane Library,Web of Science,China National Knowledge Infrastructure Database,Wanfang Database,China Science and Technology Journal Database,and Chinese Biomedical Literature *** 120 natural products were summarized,including terpenoids(51 compounds),steroidal saponins(27 compounds),phenylpropanolds(19 compounds),flavonoids(13 compounds),alkaloids(3 compounds)and others(7 compounds),most researches focus on terpenoids and part of synthetic FXR regulators were based on the structure of *** regulators could improve cholestasis and liver injury,hyperlipidemia,diabetes and *** is a potential target of treating Met *** products are characteristics with unique novel structures and special biological activity,and they are important sources of bioactive precursor compounds and drug *** the effects and mechanism of natural products and its derivative on Met S by targeting FXR may be a new way to develop the new drugs of treating Met S.

关键词： farnesoid X receptor metabolic syndrome biological products molecular docking simulation biological activity

Sodiophilicity/potassiophilicity chemistry in sodium/potassium metal anodes

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Journal of Energy Chemistry 2020年第12期29卷 1-6页

作者： Xiang Chen yun-Ke Bai Xin Shen Hong-Jie peng Qiang Zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Department of Chemical Engineering Stanford UniversityStanfordCA 94305USA

Heteroatom-doped carbon materials have been widely used as sodium(Na) and potassium(K) metal anode frameworks to achieve uniform Na and K depositions. If the origin of the Sodiophilicity and potassiophilicity of doping sites in heteroatom-doped carbon host are clearly understood, the nucleation and growth behavior of Na and K can be precisely regulated in working batteries. Herein the Sodiophilicity and potassiophilicity chemistries of carbon materials are probed through first-principles calculations. The local dipole of doping functional groups and charge transfer during Na/K deposition are regarded as key principles to reveal the sodiophilic and potassiophilic nature of doping sites. Especially, O–B, O–S, and O–P co-doping strategy are predicted to be effective methods to improve the Sodiophilicity and potassiophilicity of carbon hosts and thus render safe and dendrite-free Na and K metal anodes. This work affords a deep and insightful understanding of Sodiophilicity and potassiophilicity chemistry of Na and K anodes and establishes general principles of designing highly sodiophilic and potassiophilic carbon frameworks.

关键词： Sodium and potassium metal anodes Sodiophilicity and potassiophilicity Carbon materials First-principles calculations Dendrite-free electrode

Study on the thermo-hydraulic behaviors of the new-pattern fuel assembly in lead-based fast reactors based on OpenFOAM

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Nuclear Science and Techniques 2024年第10期35卷 250-263页

作者： yun-Xiang Li Run-Sheng Yang Yue Li Xing-kang Su Zi-Nan Huang Lu Meng Song Li Bin Xi You-peng Zhang Lu Zhang Wei Jiang Institute of Modern Physics Fudan UniversityShanghai 200433China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China

To improve the heat transfer efficiency of the coolant in lead-based fast reactors,this study optimized the configuration and rotational direction of the spacer wires in fuel assemblies to design a new-pattern fuel *** study conducted detailed comparisons between traditional and new pattern fuel assembly rod bundles utilizing the open-source computational fluid dynamics platform,*** results indicated that the new design may significantly reduce the pressure drop along the rod bundle,which is beneficial for lowering the pressure ***,this new design improved coolant mixing in the subchannels,which facilitated a more uniform temperature distribution and lower thermal gradients at the assembly *** factors collectively reduced the thermal fatigue and creep in nearby internal ***,the newpattern fuel assembly proposed in this study may have better heat transfer performance,thereby enhancing the Integrated Thermal-Hydraulic Factor by 48.2% compared to the traditional pattern.

关键词： Spacer wires Enhanced coolant mixing OpenFOAM CFD simulations

Syntheses, Crystal Structures, and Properties of Two New Lanthanide Coordination Polymers Constructed from Benzimidazole-5,6-dicarboxylic Acid

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Chinese Journal of Structural Chemistry 2019年第6期38卷 1029-1037页

作者： WANG Yong-Li WEI Zhen MAO Wei-Xi ZHOU Song-Jia GENG kang-Shua DOU yun-peng kang Yan-Fei LIAO Bo State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Hebei North University Zhangjiakou 075000China

Two lanthanide coordination polymers, {[Ln（Hbidc）（bidc）（H2 O）3]·3 H2 O}n（H3 bidc = benzimidazole-5,6-dicarboxylic acid, Ln = Eu（1）, Sm（2）） have been hydrothermally synthesized. Both compounds are isostructure and crystallize in the P21/c space group of monoclinic system. Complex 1: a = 11.087（6）, b = 8.972（5）, c = 23.064（13） ?, b = 95.027（5）o, V = 2285.4（2） ?3, Z = 4, Mr = 669.35, Dc = 1.945 g/cm3, F（000） = 1328, S = 1.044, μ = 2.827 mm-1, R = 0.0393 and wR = 0.0801 for 3458 observed reflections（I > 2s（I））. Complex 2: a = 11.087（6）, b = 8.972（5）, c = 23.064（13） ?, b = 95.027（5）°, V = 2285.4（2） ?3, Z = 4, Mr = 667.74, Dc = 1.941 g/cm3, F（000） = 1324, S = 1.071, μ = 2.652 mm-1, R = 0.0329 and wR = 0.0809 for 3744 observed reflections（I > 2s（I））. Complexes 1 and 2 have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectroscopy, and thermogravimetric analyses（TGA）. The single-crystal X-ray diffraction analysis reveals that complexes 1 and 2 are the isostructural 1 D zigzag chain structures, which are further extended into a 3 D supramolecular structure through hydrogen bonds and p···p stacking interactions. Furthermore, the thermal stability, UV-vis absorption spectra and fluorescent properties of complexes 1 and 2 have been investigated and discussed in detail.

关键词： benzimidazole-5,6-dicarboxylic acid coordination polymer crystal structure,thermal stability fluorescence properties

Effect of initial ammonium concentration on a one-stage partial nitrification/anammox biofilm system:Nitrogen removal performance and the microbial community

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Journal of Environmental Sciences 2024年第9期143卷 176-188页

作者： Mengyu Zhou yun Han Yang Zhuo Fen Yu Gaoyuan Hu Dangcong peng School of Municipal and Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Key Laboratory of Northwest Water Resource Environment and EcologyMOEXi’an University of Architecture and TechnologyXi’an 710055China

One-stage partial nitrification coupled with anammox(PN/A)technology effectively reduces the energy consumption of a biological nitrogen removal *** nitrite-oxidizing bacteria(NOB)is essential for this technology to maintain efficient nitrogen removal *** ammonium concentration(IAC)affects the degree of inhibited *** this study,the effect of the IAC on a PN/A biofilm was investigated in a moving bed biofilm *** results showed that nitrogen removal efficiency decreased from 82.49%±1.90%to 64.57%±3.96%after the IAC was reduced from 60 to 20 mg N/L,while the nitrate production ratio increased from 13.87%±0.90%to 26.50%±3.76%.NOB activity increased to1,133.86 mg N/m^(2)/day after the IAC decreased,approximately 4-fold,indicating that the IAC plays an important inhibitory role in *** rate-limiting step in the mature biofilm of the PN/A system is the nitritation process and is not shifted by the *** analysis of the microbial community structure in the biofilm indicates that the IAC was the dominant factor in changes in community *** and *** were the main anammox bacteria,and Nitrosomonas and Nitrospira were the main AOB and NOB,*** did not affect the difference in growth between *** and ***,modulating the IAC promoted the PN/A process with efficient nitrogen removal performance at medium to low ammonium concentrations.

关键词： Biological nitrogen removal Partial nitrification Anammox Ammonium concentration Biofilm

Classification of the Gut Microbiota of Patients in Intensive Care Units During Development of Sepsis and Septic Shock

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Genomics, Proteomics & Bioinformatics 2020年第6期18卷 696-707页

作者： Wanglin Liu Mingyue Cheng Jinman Li peng Zhang Hang Fan Qinghe Hu Maozhen Han Longxiang Su Huaiwu He Yigang Tong kang Ning yun Long Department of Critical Care Medicine Peking Union Medical College HospitalBeijing 100730China Key Laboratory of Molecular Biophysics of the Ministry of Education College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and EpidemiologyBeijing 100071China Beijing Advanced Innovation Center for Soft Matter Science and Engineering(BAIC-SM) College of Life Science and TechnologyBeijing University of Chemical TechnologyBeijing 100029China

The gut microbiota of intensive care unit(ICU)patients displays extreme dysbiosis associated with increased susceptibility to organ failure,sepsis,and septic ***,such dysbiosis is difficult to characterize owing to the high dimensional complexity of the gut *** tested whether the concept of enterotype can be applied to the gut microbiota of ICU patients to describe the *** collected 131 fecal samples from 64 ICU patients diagnosed with sepsis or septic shock and performed 16S rRNA gene sequencing to dissect their gut microbiota *** the development of sepsis or septic shock and during various medical treatments,the ICU patients always exhibited two dysbiotic microbiota patterns,or ICU-enterotypes,which could not be explained by host properties such as age,sex,and body mass index,or external stressors such as infection site and antibiotic ***-enterotype I(ICU E1)comprised predominantly Bacteroides and an unclassified genus of Enterobacteriaceae,while ICU-enterotype II(ICU E2)comprised predominantly *** more critically ill patients with Acute Physiology and Chronic Health Evaluation II(APACHE II)scores>18,septic shock was more likely to occur with ICU E1(P=0.041).Additionally,ICU E1 was correlated with high serum lactate levels(P=0.007).Therefore,different patterns of dysbiosis were correlated with different clinical outcomes,suggesting that ICU-enterotypes should be diagnosed as independent clinical ***,the microbial-based human index classifier we propose is precise and effective for timely monitoring of ICU-enterotypes of individual *** work is a first step toward precision medicine for septic patients based on their gut microbiota profiles.

关键词： Sepsis Septic shock Gut microbiota Enterotype Precision medicine

Analysis of mechanical strengths of extreme line casing joint considering geometric, material, and contact nonlinearities

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Petroleum Science 2024年第3期21卷 1992-2004页

作者： Ji-yun Zhang Chi peng Jian-Hong Fu Quan Cao Yu Su Jian-yun Pang Zi-Qiang Yu Petroleum Engineering School Southwest Petroleum UniversityChengdu610500SichuanChina Engineering Technology Research Institute of CNPC Southwest Oil and Gas Field Company Chengdu610017SichuanChina

To address the challenges associated with difficult casing running,limited annular space,and poor cementing quality in the completion of ultra-deep wells,the extreme line casing offers an effective solution over conventional ***,due to its smaller size,the joint strength of extreme line casing is reduced,which may cause failure when running in the *** address this issue,this study focuses on the CST-ZTΦ139.7 mm×7.72 mm extreme line casing and employs the elastic-plastic mechanics to establish a comprehensive analysis of the casing joint,taking into account the influence of geometric and material nonlinearities.A finite element model is developed to analyze the forces and deformations of the extreme line casing joint under axial tension and external collapse *** model investigates the stress distribution of each thread tooth subjected to various tensile forces and external ***,the tensile strength and crushing strength of the extreme line casing joint are determined through both analytical and experimental *** findings reveal that,under axial tensile load,the bearing surface of each thread tooth experiences uneven stress,with relatively high equivalent stress at the root of each thread *** end thread teeth are valuable spots for *** is observed that the critical fracture axial load of thread decreases linearly with the increase of thread tooth *** external pressure,the circumferential stress is highest at the small end of the external thread,leading to yield *** tensile strength of the joint obtained from the finite element model exhibits a relative error of less than 7%compared to the analytical and experimental values,proving the reliability of the finite element *** tensile strength of the joint is 3091.9 k ***,in terms of anti-collapse capability,the joints demonstrate higher resistance to collapse compared to the casing body,which is consistent with the test resul

关键词： Extreme line casing Elastic-plastic mechanics Finite element analysis Tensile strength Collapse strength