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The Electromagnetic Compatibility between FAST and Public Mobile Communication Stations and its Cognitive Using Frequency Strategy

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Research in Astronomy and Astrophysics 2022年第12期22卷 183-197页

作者： Jian Wang yi-bo zhao Ya-Fei Shi Cheng Yang Yu-Long Hao Jian-Min Sun School of Microelectronics Tianjin UniversityTianjin 300072China Qingdao Institute for Ocean Technology Tianjin UniversityQingdao 266200China Guizhou Radio Monitoring Station Guiyang 550005China

To master the electromagnetic environment characteristics around the Five-hundred-meter Aperture Spherical radio Telescope(FAST)and ensure a better ecological environment in the radio-quiet zone of FAST,we analyzed the radiation characteristics of the public communication stations around *** comparing the FAST received signal power from the communication stations and the interference protection threshold of the radio astronomy applications,we found that the total proportion of the communication stations exceeding the radio astronomy protection threshold is 69.01%.Furthermore,to fully protect the regular operation of FAST,we proposed four interference avoidance and frequency coordination strategies based on the cognitive ***:(1)increasing the operating frequency of the communication station;(2)adjusting the direction of the transmitter antennas;(3)reducing the height of the transmitter antennas;(4)decreasing the transmitting power of the communication *** a result,the impact on FAST can effectively be reduced,and the FAST's received power from the communication stations will be lower than the radio astronomy protection threshold by using the above mentioned four *** the analysis of the experiment,the prediction is consistent with the overall trend of the measurement,and using frequency strategies can significantly reduce the signal power at the receiving ***,we construct a quality evaluation system for frequency coordination and analyze the satisfaction of the four strategies under the four *** results show that adjusting the direction of the transmitter antennas has better satisfaction,and the maximum satisfaction is *** above research results can be further expanded to potentially improve the electromagnetic ecological environment around FAST and support the regular operation of FAST.

关键词： methods:analytical methods:statistical telescopes

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Impact of Startup Strategy and Buffer Tank Volume on the Compressor Inlet State for a 3-MW sCO2 Brayton Cycle

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Journal of Thermal Science 2025年第1期34卷 159-175页

作者： zhao Decai WANG bo Key Laboratory of Advanced Energy and Power Institute of Engineering Thermophysics(IET)Chinese Academy of Sciences (CAS) University of Chinese Academy of Sciences

The supercritical carbon dioxide（sCO2） Brayton cycle system has become an emerging and highly promising method of thermal power conversion due to its efficiency advantage,system compactness,and excellent adaptability of the heat *** the low carbon sCO2Brayton cycle testbed with cycle output power approaching 3 MW,a relatively detailed dynamic simulation model of the entire system is constructed to explore the dynamic response characteristics of the system with different startup strategies and different buffer tank volumes during the startup *** simulation results indicate that the smaller the volume of the buffer tank,the more rapid and obvious the parameter fluctuation in the buffer tank during the *** the allowable relative deviation limit of density is 5%,then the ratio of the buffer tank volume to the volume of the entire closed loop should not be lower than 36.80%.The strategy of simultaneous temperature and speed increase during turbine bypass start can effectively reduce the fluctuation of compressor inlet parameters and reach the steady-state more *** paper provides the recommended matching table for the opening of the turbine bypass valve（TBV） and the main regulating valve（MGV） to reduce the parameter fluctuation during the bypass *** effectiveness of the proposed turbine bypass and bypass switching startup strategy is verified by simulation,which may be used as a reference for test bench's future debugging and operation.

关键词： buffer tank dynamic characteristic dynamic model sCO2 Brayton cycle startup strategy

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Proof-of-principle experimental demonstration of quantum secure imaging based on quantum key distribution

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Chinese Physics B 2019年第10期28卷 332-337页

作者： yi-bo zhao Wan-Li Zhang Dong Wang Xiao-Tian Song Liang-Jiang Zhou Chi-Biao Ding National Key Laboratory of Microwave Imaging Technology Beijing 100190China Institute of Electronics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

We present a quantum secure imaging(QSI) scheme based on the phase encoding and weak+vacuum decoy-state BB84 protocol of quantum key distribution(QKD). It allows us to implement a computational ghost imaging(CGI) system with more simplified equipment and reconstructed algorithm by using a digital micro-mirror device(DMD) to preset the specific spatial distribution of the light intensity. What is more, the quantum bit error rate(QBER) and the secure key rate analytical functions of QKD are used to see through the intercept-resend jamming attacks and ensure the authenticity of the imaging information. In the experiment, we obtained the image of the object quickly and efficiently by measuring the signal photon counts with a single-photon detector(SPD), and achieved a secure key rate of 571.0 bps and a secure QBER of 3.99%, which is well below the lower bound of QBER of 14.51%. Besides, our imaging system uses a laser with invisible wavelength of 1550 nm, whose intensity is as low as single-photon, that can realize weak-light imaging and is immune to the stray light or air turbulence, thus it will become a better choice for quantum security radar against intercept-resend jamming attacks.

关键词： quantum secure imaging(QSI) quantum key distribution(QKD) digital micro-mirror device(DMD) quantum bit error rate(QBER)

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3D打印柔性可穿戴锂离子电池电极

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现代化工 2018年第3期38卷 81-86,88页

作者：王一博赵九蓬哈尔滨工业大学化工与化学学院黑龙江哈尔滨150001

提出了一种利用挤出式3D打印技术制备纺织物结构的自支撑柔性锂离子电池电极的新方法。并采用高浓度的聚偏氟乙烯(PVDF)作黏度调节剂,碳纳米管(CNT)作导电剂,磷酸铁锂和钛酸锂作电极活性材料,配制了具有可打印性的"墨水",其表观黏度接近... 详细信息

提出了一种利用挤出式3D打印技术制备纺织物结构的自支撑柔性锂离子电池电极的新方法。并采用高浓度的聚偏氟乙烯(PVDF)作黏度调节剂,碳纳米管(CNT)作导电剂,磷酸铁锂和钛酸锂作电极活性材料,配制了具有可打印性的"墨水",其表观黏度接近10~5Pa·s,并且表现出明显的剪切变稀;同时此"墨水"的存储模量平台值也高达10~5Pa,其优异的流变学性质对于打印和固化过程十分有利。电化学测试结果表明,2种打印电极具有稳定且十分匹配的充放电比容量,因此由二者组装的软包袋装全电池也具有高达约108 mAh/g的放电比容量(50 mA/g),弯曲后,在同样的电流密度下其放电比容量保持在约111 mAh/g。

关键词：柔性/可穿戴电子学打印电极 3D打印技术锂离子电池

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Recent advances of metal vacancies in energy and environmental catalysis:Synthesis,characterization,and roles

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Green Energy & Environment 2025年第1期10卷 84-108页

作者： Long Sun Shunzheng zhao Sirui Gao Ronghui Zhu yiran Tan Xiaolong Tang Honghong yi School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Beijing100083China

With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective ***,being one of the hallmarks of modern industry,offers a promising avenue for ***,the question of how to significantly enhance the performance of catalysts has gradually drawn the attention of *** engineering,a commonly employed and effective approach to improve catalyst activity,has become a significant research focus in the catalysis field in recent *** vacancies have received extensive attention due to their simple ***,exploration of metal vacancies has remained stagnant for a considerable period,resulting in a scarcity of comprehensive reviews on this ***,based on the latest research findings,this paper summarizes and consolidates the construction strategies for metal vacancies,characterization techniques,and their roles in typical energy and environmental catalytic ***,it outlines potential challenges in the future,aiming to provide valuable references for researchers interested in investigating metal vacancies.

关键词： Metal vacancies Catalysis Construction strategies Characterization techniques Roles

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Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2982-2997页

作者： Hongli Li Jianhua Huang Di zhao Lemei Zhu Zheyu Zhang Min yi Weijun Peng Department of Integrated Traditional Chinese&Western Medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina National Clinical Research Center for Metabolic Diseases ChangshaHunan ProvinceChina Hunan Academy of Chinese Medicine ChangshaHunan ProvinceChina Academician Workstation Changsha Medical UniversityChangshaHunan ProvinceChina

Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut *** aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease *** do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of ***-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 ***,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 *** findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies.

关键词： Alzheimer’s disease APP/PS1 mice brain-kidney axis gut microbiota heart-brain axis liver-brain axis lung-brain axis microbiota-gut-brain axis peripheral organ metabolism spleen-brain axis

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Application of the improved dung beetle optimizer,muti-head attention and hybrid deep learning algorithms to groundwater depth prediction in the Ningxia area,China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 18-23页

作者： Jiarui Cai bo Sun Huijun Wang yi Zheng Siyu Zhou Huixin Li Yanyan Huang Peishu Zong Collaborative Innovation Center on forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjingChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) ZhuhaiChina China Meteorological Administration Key Laboratory of Transportation MeteorologyNanjingChina Jiangsu Meteorological Observatory NanjingChina

Due to the lack of accurate data and complex parameterization,the prediction of groundwater depth is a chal-lenge for numerical *** learning can effectively solve this issue and has been proven useful in the prediction of groundwater depth in many *** this study,two new models are applied to the prediction of groundwater depth in the Ningxia area,*** two models combine the improved dung beetle optimizer(Dbo)algorithm with two deep learning models:The Multi-head Attention-Convolution Neural Network-Long Short Term Memory networks(MH-CNN-LSTM)and the Multi-head Attention-Convolution Neural Network-Gated Recurrent Unit(MH-CNN-GRU).The models with Dbo show better prediction performance,with larger R(correlation coefficient),RPD(residual prediction deviation),and lower RMSE(root-mean-square error).Com-pared with the models with the original Dbo,the R and RPD of models with the improved Dbo increase by over 1.5%,and the RMSE decreases by over 1.8%,indicating better prediction *** addition,compared with the multiple linear regression model,a traditional statistical model,deep learning models have better prediction performance.

关键词： Groundwater depth Multi-head attention Improved dung beetle optimizer CNN-LSTM CNN-GRU Ningxia

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CoTCPP integrates with BiOBr microspheres for improved solar-driven CO_(2)reduction performance

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Green Energy & Environment 2025年第1期10卷 193-202页

作者： Lina Li yi Zhang Gaopeng Liu Tiange Wei Junze zhao Bin Wang Mengxia Ji Yuanbin She Jiexiang Xia Huaming Li School of Chemistry and Chemical Engineering Institute for Energy ResearchJiangsu University301 Xuefu RoadZhenjiang212013China State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

CO_(2) photoreduction into carbon-based chemicals has been considered as an appropriate way to alleviate the energy issue and greenhouse ***,the 5,10,15,20-tetra(4-carboxyphenyl)porphyrin cobalt(II)(CoTCPP)has been integrated with BiOBr microspheres and formed the CoTCPP/BiOBr *** as-prepared CoTCPP/BiOBr-2 composite shows optimized photocatalytic performance for CO_(2) conversion into CO and CH_(4) upon irradiation with 300 W Xe lamp,which is 2.03 and 2.58 times compared to that of BiOBr,*** introduced CoTCPP significantly enhanced light absorption properties,promoted rapid separation of photogenerated carriers and boosted the chemisorption of CO_(2) *** metal Co^(2+) at the center of the porphyrin molecules also acts as adsorption center for CO_(2) molecules,accelerating the CO_(2) conversion into CO and *** possible mechanism of CO_(2) photoreduction was explored by in-situ FT-IR *** work offers a new possibility for the preparation of advanced photocatalysts.

关键词： BiOBr CoTCPP CO_(2)photoreduction Carriers transfer CO_(2)adsorption-activation

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Formation and evolution of supercritical geofluid

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Science China Earth Sciences 2025年第1期68卷 39-51页

作者： Huaiwei NI yilin XIAO Xiaolin XIONG Xiandong LIU Chunxiao GAO yi-Xiang CHEN Yunguo LI Wan-Cai LI Xuan GUO Yang-Yang WANG Dong-bo TAN Li ZHANG State Key Laboratory of Lithospheric and Environmental Coevolution University of Science and Technology of China Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of China Guangzhou Institute of Geochemistry Chinese Academy of Sciences School of Earth Sciences and Engineering Nanjing University State Key Lab of Superhard Materials Jilin University

In this work, we provide a comprehensive review on the formation, evolution, properties, and effects of supercritical geofluid. In Earth's interior, enhanced miscibility between H2O and silicate by the addition of special components or by the increase of pressure and temperature gives rise to supercritical geofluid with a significant amount of both H2O and silicate *** formation of supercritical geofluid in magmatic-hydrothermal systems, typified by pegmatite system, is governed by meltfluid critical curve. The formation of supercritical geofluid in metamorphic systems, typified by subducted slab, is governed by the second critical end point. Experimental results suggest that the presence of boron and fluorine in pegmatite system makes it possible to form supercritical geofluid at crustal depths, but the release of supercritical geofluid from subducted slab is withheld until almost 100 km depth. A major presence of both H2O and depolymerized structural units（monomers, dimers, etc.） endows supercritical geofluid with unique physical properties including low density, low elastic moduli, low viscosity, high diffusivity,and high electrical conductivity. Supercritical geofluid can effectively mobilize a variety of elements even including high field strength elements and heavy rare earth elements. The chemical signatures of supercritical geofluid can be inherited by metasomatized mantle and mantle-derived melts, and this could give an explanation of the oxidation of arc magmas. Phase separation of supercritical geofluid through the mechanism of spinodal decomposition leads to formation of a melt network. Multiphase fluid inclusions recovered from subduction zone rocks and pegmatites are possible relics of supercritical geofluid. Supercritical geofluid can cause electrical anomaly and low seismic velocity near the top of subducted slab, and can be linked with intermediate-focus earthquakes. Supercritical geofluid may have played a crucial role in the formation of pe

关键词： Supercritical geofluid Miscibility Subduction zone Pegmatite

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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-bo Li Qi Zhang Jun-zhao Xiao yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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