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Rapid instrument exchanging system for the Cassegrain focus of the Lijiang 2.4-m Telescope

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Research in Astronomy and Astrophysics 2015年第6期15卷 918-928页

作者： yu-feng fan Jin-Ming Bai Ju-Jia Zhang Chuan-Jun Wang Liang Chang yu-Xin Xin Rui-Long Zhang yunnan Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences

As a facility used for astronomical research, the Lijiang 2.4-m telescope of yunnan Astronomical Observatories, requires the ability to change one auxiliary instrument with another in as short a time as possible. This arises from the need to quickly respond to scientific programs （e.g. transient observation, time domain studies） and changes in observation conditions （e.g. seeing and weather conditions）. In this paper, we describe the design, construction and test of hardware and software in the rapid instrument exchange system （RIES） for the Cassegrain focal station of this telescope, which enables instruments to be quickly changed at night without much loss of observing time. Tests in the laboratory and at the telescope show that the image quality and pointing accuracy of RIES are satisfactory. With RIES, we observed the same Landolt standard stars almost at the same time with the Princeton Instruments VersArray 1300B Camera （PICCD） and the yunnan Faint Object Spectrograph and Camera （YFOSC）, while both were mounted at the Cassegrain focus. A quasi-simultaneous comparison shows that the image quality of the optical system inside the YFOSC is comparable with that provided by the PICCD.

关键词： telescopes Lijiang 2.4-m Telescope -- instrumentation photometers -- instrumentation spectrographs -- telescopes automation

Layered metastructure containing freely-designed local resonators for wave attenuation

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Defence Technology（防务技术） 2024年第2期32卷 23-31页

作者： yu Li Huguang He Jiang feng Hailong Chen fengnian Jin Hualin fan State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007China Rocket Force University of Engineering Xi'an 710025China Henan International Joint Laboratory of Dynamics of Impact and Disaster of Engineering Structures Department of Civil EngineeringNanyang Institute of TechnologyNanyang 473004China Guangxi Key Laboratory of Disaster Prevention and Engineering Safety and Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing 210016China

Combining periodic layered structure with three-dimensional cylindrical local resonators,a hybrid metastructure with improved wave isolation ability was designed and investigated through theoretical and numerical *** metastructure is composed of periodic rubber layers and concrete layers embedded with three-dimensional resonators,which can be freely designed with multi local resonant frequencies to attenuate vibrations at required frequencies and widen the attenuation *** metastructure can also effectively attenuate seismic *** with layered rubber-based structures,the metastructure has more excellent wave attenuation effects with greater attenuation and wider bandgap.

关键词： Layered metastructure Local resonator Wave attenuation

Microstructure evolution,mechanical properties and fracture behavior of Al-xSi/AZ91D bimetallic composites prepared by a compound casting

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Journal of Magnesium and Alloys 2024年第5期12卷 1944-1964页

作者： Guangyu Li Wenming Jiang feng Guan Junwen Zhu Yang yu Zitian fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

In this paper,the effect of the Si content on microstructure evolution,mechanical properties,and fracture behavior of the Al-xSi/AZ91D bimetallic composites prepared by compound casting was investigated *** obtained results showed that all the Al-xSi/AZ91D bimetallic composites had a metallurgical reaction layer(MRL),whose thickness increased with increasing Si content for the hypoeutectic Al-Si/AZ91D composites,while the hypereutectic Al-Si/AZ91D composites were *** MRL included eutectic layer(E layer),intermetallic compound layer(IMC layer)and transition region layer(T layer).In the IMC layer,the hypereutectic Al-Si/AZ91D composites contained some Si solid solution and flocculent Mg_(2)Si+Al-Mg IMCs phases not presented in the hypoeutectic Al-Si/AZ91D ***,increasing Si content,the thickness proportion of the T layer increased,forming an inconsistent preferred orientation of the *** shear strengths of the Al-xSi/AZ91D bimetallic composites enhanced with increasing Si content,and the Al-15Si/AZ91D composite obtained a maximum shear strength of 58.6 MPa,which was 73.4% higher than the Al-6Si/AZ91D *** fractures of the Al-xSi/AZ91D bimetallic composites transformed from the T layer into the E layer with the increase of the Si *** improvement of the shear strength of the Al-xSi/AZ91D bimetallic composites was attributed to the synergistic action of the Mg_(2)Si particle reinforcement,the reduction of oxidizing inclusions and the ratio of Al-Mg IMCs as well as the orientation change of the MRL.

关键词： Al/Mg bimetallic composites Si content Mg_(2)Si reinforcement Microstructure Mechanical properties Fracture behavior

Rapid lithium-ion insertion/extraction and migration behavior of Na_(2)WO_(4)-encapsulated lithium-rich layered oxide cathode

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Rare Metals 2024年第8期43卷 3647-3660页

作者： yu-Shen Zhao fan-fan Wang Jian-Cang Wang Peng-Fei Wang Ting-feng Yi Jun-Hong Zhang School of Materials Science and Engineering Northeastern UniversityShenyangShenyang 110819China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology College of Chemistry and Chemical EngineeringLiaocheng UniversityLiaocheng 252059China

Due to the low cost,high working voltage and high storage capacity,Li-rich Mn-based layered compounds show promise as the cathode materials for lithiumion batteries(LIBs).However,the side reactions at the solid-liquid interface of the cathode will lead to rapid capacity decay and inferior rate ***,this article proposes a liquid-phase dispersion strategy to introduce a Na_(2)WO_(4)layer on the Li_(1.2)Ni_(0.13)-Co_(0.13)Mn_(0.54)O_(2) cathode,which can reduce the side effects between raw materials and electrolyte and promote the insertion/extraction rate of Li^(+),thus enhancing the material stability and rate *** a result,the capacity retention rate is 96.9%after 200 cycles under ***,the capacities are 177.5,149.5,111.1 and58.3 mAh·g^(-1)at 1C,2C,5C and 10C,implying a superior fast charging *** exceptional performance can be ascribed to both the increased conductivity and enhanced structural stability of the cathode ***'s more,based on the investigation of ion insertion/extraction behavior in electrode materials and the ion migration kinetics in the electrolyte,this study suggests that coating Li-rich Mn-based materials with Na_(2)WO_(4)can be a promising strategy to improve their performance in LIBs.

关键词： Li-ion battery Coating Rate performance Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2) Reaction kinetics

Phase separation of GRP7 facilitated by FERONIAmediated phosphorylation inhibits mRNA translation to modulate plant temperature resilience

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Molecular Plant 2024年第3期17卷 460-477页

作者： fan Xu Long Wang Yingbin Li Junfeng Shi Dorothee Staiger feng yu state Key Laboratory of Chemo/Biosensing and Chemometrics College of Biologyand Hunan Key Laboratory of Plant Functional Genomics and Developmental RegulationHunanUniversityChangsha 410082P.R.China State Key Laboratory of Hybrid Rice Hunan Agricultural Biotechnology Research InstituteHunan Academy of Agricultural SciencesChangsha 410125P.R.China RNA Biology and Molecular Physiology Faculty of BiologyBielefeld University33615 BielefeldGermany

Changes in ambient temperature profoundly affect plant growth and ***,the molecu-larbasis of plant acclimation to temperature fluctuation is of great *** this study,we discovered that GLYCINE-RICH RNA-BINDING PROTEIN 7(GRP7)contributes to cold and heat tolerance in Arabidopsis *** found that exposure to a warm temperature rapidly induces GRP7 condensates in planta,which can be reversed by transfer to a lower *** biology and biochemical assays revealed that GRP7 undergoes liquid-liquid phase separation(LLPS)in vivo and in *** of GRP7 in the cyto-plasm contributes to the formation of stress granules that recruit RNA,along with the translation machinery component eukaryotic initiation factor 4E1(elF4E1)and the mRNA chaperones COLD SHOCK PROTEIN 1(CSP1)and CSP3,to inhibit ***,natural variations in GRP7 affecting the residue phos-phorylated by the receptorkinase FERONIA alter its capacity to undergo LLPS and correlate with the adap-tation of some Arabidopsis accessions to a widertemperature *** together,ourfindings illustrate the role of translational control mediated by GRP7 LLPS to confer plants with temperature resilience.

关键词： fluctuating temperature glycine-rich RNA-binding protein phase separation cold shock proteins translation

Application of GNSS-PPP on Dynamic Deformation Monitoring of Offshore Platforms

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China Ocean Engineering 2024年第2期38卷 352-361页

作者： yu Li-na XIONG Kuan GAO Xi-feng LI Zhi fan Li-long ZHANG Kai Institute of Ocean Energy and Intelligent Construction Tianjin University of TechnologyTianjin 300384China China Railway Construction Bridge Engineering Bureau Group Co.LTD Tianjin 300300China School of Civil Engineering Tianjin UniversityTianjin 300072China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong KongChina State Key Laboratory of Precision Blasting Jianghan UniversityWuhan 430056China

The real-time dynamic deformation monitoring of offshore platforms under environmental excitation is crucial to their safe *** Global Navigation Satellite System-Precise Point Positioning(GNSS-PPP)has been considered for this purpose,its monitoring accuracy is relatively ***,the influence of background noise on the dynamic monitoring accuracy of GNSS-PPP remains ***,it is imperative to further validate the feasibility of GNSS-PPP for deformation monitoring of offshore *** address these concerns,vibration table tests with different amplitudes and frequencies are *** results demonstrate that GNSS-PPP can effectively monitor horizontal vibration displacement as low as±30 mm,which is consistent with ***,the spectral characteristic of background noise in GNSS-PPP is similar to that of GNSS-RTK(Real Time Kinematic).Building on this observation,an improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)has been proposed to de-noise the data and enhance the dynamic monitoring accuracy of *** monitoring application research is also undertaken,successfully extracting and analyzing the dynamic deformation of an offshore platform structure under environmental excitation using GNSS-PPP monitoring in conjunction with improved CEEMDAN *** comparing the de-noised dynamic deformation trajectories of the offshore platform during different periods,it is observed that the platform exhibits reversible alternating vibration responses under environmental excitation,with more pronounced displacement deformation in the direction of load *** research results confirm the feasibility and potential of GNSS-PPP for dynamic deformation monitoring of offshore platforms.

关键词： GNSS-PPP offshore platform dynamic deformation monitoring improved CEEMDAN de-noising

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-Lin fan feng Zhang Qian Chen Hao-Chen Song Lu-yu Zhong yue-Xiang Dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and ***,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal *** this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection *** spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response *** with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal *** approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal *** accuracy level is ten times higher compared to density accuracy calculated using calibration ***,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density Perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration

Rational design of metal selenides nanomaterials for alkali metal ion(Li^(+)/Na^(+)/K^(+))batteries:current status and perspectives

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Rare Metals 2024年第5期43卷 1906-1931页

作者： Rui Sun feng Xu Cai-Hong Wang Sheng-Jun Lu yu-Fei Zhang Hao-Sen fan College of Materials Science and Metallurgy Engineering Guizhou UniversityGuiyang550025China School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou510006China

Recently,metal selenides have obtained widespread attention as electrode materials for alkali(Li^(+)/Na^(+)/K^(+))batteries due to their promising theoretical capacity and ***,metal selenides,similar to metal oxides and sulfides,also suffer from severe volume explosion during repeated charge/discharge processes,which results in the structure collapse and the following pulverization of electrode ***,it leads to poor cycle stability and influencing their further *** order to solve these issues,some special strategies,including elemental doping,coupling with carbon materials,synthesis of the bimetal selenides with heterostructure,etc.,have been gradually applied to design novel electrode materials with outstanding electrochemical ***,the recent research progress on metal selenides as anodes for alkali ion batteries is summarized,including the regulation of crystal structure,synthesis strategies,modification methods,and electrochemical mechanisms and ***,the challenges of metal selenides and the perspective for future electrode material design are *** is hoped to pave a way for the development of metal selenide electrode materials for the potential applications for alkali metal ion(Li^(+)/Na^(+)/K^(+))batteries.

关键词： Rational design Metal selenides Nanostructure Li^(+) batteries Na^(+) batteries K^(+) batteries

Assembling ionic liquid into porous molecular filler of mixed matrix membrane to trigger high gas permeability,selectivity,and stability for CO_(2)/CH_(4) separation

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Nano Research 2024年第5期17卷 4535-4543页

作者： Liting yu Liqin Hao Yang feng Jia Pang Mengwei Guo Liangjun Li Weidong fan Lili fan Rongming Wang Zixi Kang Daofeng Sun School of Materials Science and Engineering State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum(East China)Qingdao 266580China College of Chemistry Nankai UniversityTianjin 300071China College of Chemistry and Chemical Engineering China University of Petroleum(East China)Qingdao 266580China College of New Energy China University of Petroleum(East China)Qingdao 266580China

As an emerging zero-dimensional nano crystalline porous material,porous organic cages(POCs)with soluble properties in organic solvents,are promising candidates as molecular fillers in mixed matrix membranes(MMMs).The pore structure of POCs should be adjusted to trigger efficient gas separation performance,and the interaction between filler and matrix should be *** this work,ionic liquid(IL)was introduced into the molecular fillers of CC3,to construct the IL@CC3/PIM-1 membrane to effectively separate CO_(2) from CH_(4).The advantages of doping IL include:(1)narrowing the cavity size of POCs from 4.4 to 3.9Åto enhance the diffusion selectivity,(2)strengthening the CO_(2) solubility to heighten the gas permeability,and(3)improving the compatibility between filler and matrix to upgrade membrane *** the optimization of the membrane composite,the IL@CC3/PIM-1-10%membrane possesses the CO_(2) permeability of 7868 Barrer and the CO_(2)/CH_(4) selectivity of 73.4,which compared to the CC3/PIM-1-10%membrane,improved by 15.9%and 106.2%,***,the membrane has maintained a stable separation performance at varied temperatures and pressures during the long-term *** proposed method offers an efficient way to improve the performance of POCs-based MMMs in gas separation.

关键词： porous organic cage mixed matrix membrane ionic liquid gas separation