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Atmospheric and Oceanic Science Letters 2024年第1期17卷 28-33页

作者： Yimin Liu wei Yu Jilan jiang Tingting Ma jiangyu mao Guoxiong Wu State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina School of Atmospheric Sciences Sun Yat-sen UniversitySouthern Marine Science and Engineering Guangdong Laboratory(Zhuhai)ZhuhaiChina Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen UniversityZhuhaiChina

本文回顾了青藏高原桥梁作用方面的最新研究进展,涉及北大西洋气候异常对春,夏亚洲季风和厄尔尼诺-南方涛动(ENSO)事件的遥相关影响,热带海洋异常和中国东部极端气候异常之间的联系以及华南春雨的季节内变化等.介绍了年际时间尺度上,冬... 详细信息

本文回顾了青藏高原桥梁作用方面的最新研究进展,涉及北大西洋气候异常对春,夏亚洲季风和厄尔尼诺-南方涛动(ENSO)事件的遥相关影响,热带海洋异常和中国东部极端气候异常之间的联系以及华南春雨的季节内变化等.介绍了年际时间尺度上,冬-春季北大西洋海表温度强迫如何影响南亚季风的季节性转变以及随后ENSO事件的触发.5月份青藏高原上空显著的负感热斜压结构,为北大西洋影响亚洲季风和ENSO提供了桥梁效应,夏季北大西洋涛动与华东夏季降水变化显著相关,高原潜热在这一关系中起着桥梁作用.另一方面,这种高原桥梁效应也存在于从热带海洋异常到东亚夏季极端降水事件的连接中,以及从中纬度波列到华南春雨准双周振荡的联系中.

关键词：青藏高原桥梁作用遥相关北大西洋厄尔尼诺-南方涛动热带对流气候异常和极端事件

Development of a Front End Array for Broadband Phased Array Receiver

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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

High toughness and CMAS resistance of REAlO_(3)/RE_(2)Zr_(2)O_(7)(RE=La,Nd,Sm,Eu,Gd,and Dy)composites with eutectic composition for thermal barrier coatings

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Journal of Advanced Ceramics 2024年第6期13卷 800-809页

作者： Zijian Zhang jian Sun Guanghua Liu Yi Han wei Liu Yi Li wei Wang Xiangyang Liu Peng Zhang wei Pan Chunlei Wan State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China China United Gas Turbine Technology Co. Ltd.Beijing 100015China College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

Although rare earth zirconates(RE_(2)Zr_(2)O_(7))have garnered attention as viable candidates for thermal barrier coatings(TBCs),they suffer from low fracture toughness and accelerated calcium–magnesium–alumina–silicate(CMAS)melt corrosion at high service temperatures,which impedes their practical *** this work,we developed a series of REAlO_(3)/RE_(2)Zr_(2)O_(7)(RE=La,Nd,Sm,Eu,Gd,and Dy)composites with a eutectic composition that not only significantly enhanced the fracture toughness by more than 40%relative to that of RE_(2)Zr_(2)O_(7)but also exhibited improved resistance to CMAS *** increase in toughness arises from multiple mechanisms,such as ferroelastic toughening,fine-grain strengthening,and residual stress toughening,all of which trigger more crack defects and energy ***,the CMAS penetration depth of the REAlO_(3)/RE_(2)Zr_(2)O_(7)composites is approximately 36%lower than that of RE_(2)Zr_(2)O_(7).Al–O constituents in composites can capture CaO,SiO_(2),and MgO in CMAS melts and increase their viscosity,resulting in enhanced CMAS corrosion *** thermophysical properties of the REAlO_(3)/RE_(2)Zr_(2)O_(7)composites were also investigated,and their coefficient of thermal expansion and thermal conductivity are comparable to those of 7–8 wt%Y_(2)O_(3)partially stabilized ZrO2(YSZ),indicating their potential as TBC materials.

关键词： fracture toughness thermal property calcium-magnesium-alumina-silicate(CMAS)corrosion REAlO_(3)/RE_(2)Zr_(2)O_(7) eutectic composition

Measurement of atmospheric non-reciprocity effects for satellite-based two-way time-frequency transfer

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Photonics Research 2024年第6期12卷 1274-1282页

作者： TING ZENG QI SHEN YUAN CAO jian-YU GUAN MENG-ZHE LIAN JIN-jian HAN LEI HOU jian LU XIN-XIN PENG MIN LI wei-YUE LIU JIN-CAI WU YONG WANG JUAN YIN JI-GANG REN HAI-FENG jianG QIANG ZHANG CHENG-ZHI PENG jian-wei PAN Hefei National Research Center for Physical Sciences at the Microscale and School of Physical Sciences University of Science and Technology of ChinaHefei 230026China Shanghai Research Center for Quantum Science and CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaShanghai 201315China Hefei National Laboratory University of Science and Technology of ChinaHefei 230094China Faculty of Information Science and Engineering Ningbo UniversityNingbo 315211China Key Laboratory of Space Active Opto-Electronic Technology Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

Future optical clock networks will require high-precision optical time-frequency transfer between satellites and ground ***,due to atmospheric turbulence,satellite motion and time delay between the satellite–ground transmission links will cause spatial and temporal variations,respectively,resulting in the breakdown of the time-of-flight reciprocity on which optical two-way time-frequency transfer is ***,we experimentally simulate the atmospheric effects by two-way spatio-temporally separated links between two stationary terminals located 113 km apart and measure the effects for optical two-way time-frequency *** experiment shows that the effect on the link instability is less than 2.3×10^(−19) at 10,000 *** indicates that when the link instability of satellite-ground optical time-frequency transfer is on the order of 10^(−19),it is not necessary to consider the atmospheric non-reciprocity effects.

关键词： breakdown transfer satellite

Preparation and Rheological Characterization of Long Chain Branching Polyglycolide

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Chinese Journal of Polymer Science 2024年第8期42卷 1177-1184页

作者： wei-Lin Liu Ming-Fu Lyu Heng-Yuan Zhang jian-Ye Liu Shi-Jun Zhang Beijing University of Chemical Technology Beijing 100029China SINOPEC(Beijing)Research Institute of Chemical Industry Co. Ltd.Beijing 100013China

The long chain branching(LCB)polyglycolide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher viscosity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are *** melt strength of PGA is finally improved greatly and can make su re that the supercritical CO_(2)foaming can be carried out successfully.

关键词： Polyglycolide(PGA) Long chain branching(LCB) Rheology

Investigation of wake-induced vibration interference between two staggered wave-cone cylinders at subcritical Reynolds number

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Journal of Hydrodynamics 2024年第2期36卷 378-393页

作者： Lin Zou Di-wei Liu jian Liu Hong-cheng Zuo Yin-huan Zheng Hao Xia School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan430070China Department of Aeronautical and Automotive Engineering Loughborough UniversityLoughboroughUK

The wake induced vibration(WIV)of a one-and two-degree-of-freedom(1DOF,2DOF)downstream wave-cone cylinder(WCC)behind a stationary equal-size upstream wave-cone cylinder in the staggered arrangement is numerically investigated at subcritical Reynolds number of 3900 by using shear stressed transfer(SST)k-ωturbulence *** streamwise pitch ratios(P/Dm)vary from 4 to 6 with a fixed incident angleα=8°.Experimental measurements were also performed for the validation of the present numerical *** is found that the largest vibration amplitude in crossflow direction occurred at P/Dm=4,Ur=8 with small difference of streamwise vibration at P/Dm=4,*** from single wavy-cone cylinder(SWCC),the downstream flexible one of a pair staggered WCCs got larger vibration amplitude during phase switching stage instead of in-phase *** upstream wake will suppress the triple frequency of main frequency in the power spectra density(PSD)functions of Cl but stimulate the double one of *** intriguing vibration mechanism happened in all 2DOF cases where the trajectory of downstream WCC is a significant ellipse rather than a figure of *** transformation of phase switching and the variation of the main frequency of drag coefficient(Cd)can be explained by the vortex-shedding modes of downstream WCC.

关键词： Two wave-cone cylinders staggered arrangement wake induced vibration phase switching vortex shedding

Defect-modulated and heteroatom-functionalized Ti_(3−x)C_(2)T_(y)MXene 3D nanocavities induce growth of MoSe_(2)nanoflakes toward electrocatalytic hydrogen evolution in all pH electrolytes

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Nano Research 2024年第7期17卷 6294-6304页

作者： Ming Du Xianzhi Yang jian Zhang wei Chen Huajie Huang Xinbao Zhu Xing’ao Li State Key Laboratory for Organic Electronics and Information Displays and Institute of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Centre for Advanced Materials(SICAM)Nanjing University of Posts and Telecommunications(NJUPT)Nanjing 210023China College of Electronic and Optical Engineering and College of Flexible Electronics Nanjing University of Posts and Telecommunications(NJUPT) Nanjing 210023China New Energy Technology Engineering Lab of jiangsu Province College of ScienceNanjing University of Posts and Telecommunications(NJUPT)Nanjing 210023China College of Pharmaceutical and Chemical Engineering Taizhou UniversityJiaojiang 318000China College of Mechanics and Materials Hohai UniversityNanjing 210098China College of Chemical Engineering Nanjing Forestry UniversityNanjing 210037China

Reducing kinetic energy barriers and developing accessible active sites are critical to deliver high hydrogen evolution reaction(HER)*** this paper,we synthesized defect-modulated and heteroatom(boron)-functionalized three-dimensional(3D)bowl-shaped Ti_(3−x)C_(2)T_(y)MXene(B-TCT)nanocavities coupled with the vertical growth of MoSe_(2)*** B-TCT@MoSe_(2)nanohybrids catalyst delivers the overpotentials of 49.9,52.7,and 67.8 mV to reach a HER current density of 10 mA·cm^(−2)under acidic,alkaline,and neutral conditions,*** outstanding HER activity is predominantly attributed to the heteroatom functionalization,self-adapting Ti vacancy(VTi)defect modulation,and spatial configuration design in the 3D B-TCT nanocavity,which synergistically regulate the electronic structure,activate the basal plane/edge unsaturated sites,and reduce the reaction energy *** and theoretical calculations demonstrate that strong heterogeneous interfacial bonding interactions between B-TCT and MoSe_(2)can dramatically reduce the free energy of hydrogen adsorption and facilitate efficient interfacial charge migration,thus essentially improving the HER *** used this 3D porous nanohybrid system assembled by defectrich lamellar structures to elucidate the advantageous synergistic effects of multiple mechanisms among defect structure,heteroatom functionalization,and interfacial coupling,which provided important insights for the development of efficient hybridtype catalysts.

关键词： electrocatalytic H_(2)evolution three-dimensional(3D)MXene nanocavity MoSe_(2)nanoflake self-adapting Ti vacancy defect heteroatom-functionalized interfacial interaction

Progress in preparation of AlN-reinforced magnesium matrix composites:A review

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China Foundry 2024年第1期21卷 1-10页

作者： Lu Chen Shu-lin Lü Di-jia Zhao wei Guo jian-yu Li Shu-sen Wu State Key Lab of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

As a ceramic material,AlN has very good thermophysical and mechanical *** addition,AlN is an effective refining agent for Mg alloys because it has a lattice constant similar to that of ***,AlN is an ideal reinforcement for magnesium matrix composites(MMCs),and is attracting increasing *** review addresses the development of preparation technologies for AlN-reinforced Mg matrix *** mainstream preparation techniques include stir casting,melt infiltration,powder metallurgy,and in-situ *** addition,the advantages and disadvantages of these techniques are analyzed in depth,and it is pointed out that the next direction for the preparation of high-performance AlN-reinforced MMCs is less aluminization and multiple technologies integration.

关键词： AlN MMCs preparation thermophysical property mechanical property

Effect of a systemic intervention combined with a psychological intervention in stroke patients with oropharyngeal dysfunction

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World Journal of Psychiatry 2024年第6期14卷 904-912页

作者： Jie Song jian-Dong Wang Di Chen Jing Chen Jin-Feng Huang mao Fang Second Ward Department of NeurologyThe Second Affiliated Hospital of Qiqihar Medical CollegeQiqihar 161006Heilongjiang ProvinceChina Third Ward Department of NeurologyThe Second Affiliated Hospital of Qiqihar Medical CollegeQiqihar 161006Heilongjiang ProvinceChina

BACKGROUND Stroke frequently results in oropharyngeal dysfunction(OD),leading to difficulties in swallowing and eating,as well as triggering negative emotions,malnutrition,and aspiration pneumonia,which can be detrimental to ***,routine nursing interventions often fail to address these issues *** and psychological interventions can improve dysphagia symptoms,relieve negative emotions,and improve quality of ***,there are few clinical reports of systemic interventions combined with psychological interventions for stroke patients with *** To explore the effects of combining systemic and psychological interventions in stroke patients with *** This retrospective study included 90 stroke patients with OD,admitted to the Second Affiliated Hospital of Qiqihar Medical College(January 2022–December 2023),who were divided into two groups:regular and *** function grading(using a water swallow test),swallowing function[using the standardized swallowing assessment(SSA)],negative emotions[using the selfrating anxiety scale(SAS)and self-rating depression scale(SDS)],and quality of life(SWAL-QOL)were compared between groups before and after the intervention;aspiration pneumonia incidence was *** Post-intervention,the coalition group had a greater number of patients with grade 1 swallowing function compared to the regular group,while the number of patients with grade 5 swallowing function was lower than that in the regular group(P<0.05).Post-intervention,the SSA,SAS,and SDS scores of both groups decreased,with a more significant decrease observed in the coalition group(P<0.05).Additionally,the total SWAL-QOL score in both groups increased,with a more significant increase observed in the coalition group(P<0.05).During the intervention period,the total incidence of aspiration and aspiration pneumonia in the coalition group was lower than that in the control group(4.44%vs 20.00%;P<0.05).CONCLUSION Systemic int

关键词： Stroke Oropharyngeal dysfunction Systemic interventions Psychological intervention Curative effect Negative emotion

Manipulation of internal blockage in triangular triple quantum dot

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Chinese Physics B 2024年第5期33卷 588-593页

作者：齐月魏建华 Department of Physics Renmin UniversityBeijing 100876China

We utilize the calculation of hierarchical equations of motion to demonstrate that the spin-dependent properties between adjacent quantum dots(QDs)can be changed by breaking the internal symmetry configuration,corresponding to the inversion of dominant chiral *** the linear triple quantum dots(LTQDs)connected to two electron reservoirs,we can observe that the blockage appears at the triangle triple quantum dots(TTQDs)by gradually increasing the coupling strength between next-nearest double *** the initial coupling between LTQDs has altered,the internal chiral circulation also undergoes the corresponding transform,thus achieving qualitative regulation and detection of the blocking *** also investigate the response of the chiral circulation to the dot–lead coupling strength,indicating the overall robust chiral circulation of the TTQDs frustration.

关键词： quantum dots chiral topology blocking