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Autonomous navigation of an asteroid orbiter enhanced by a beacon satellite in a high-altitude orbit

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Astrodynamics 2024年第3期8卷 375-400页

作者： Weidong Yin Yu Shi Leizheng shu yang gao University of Chinese Academy of Sciences Beijing100049China Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing100094China

This study aims to assess the autonomous navigation performance of an asteroid orbiter enhanced using an inter-satellite link to a beacon *** navigation includes the orbit determination of the orbiter and beacon,and asteroid gravity estimation without any ground station *** measurements were acquired using satellite-to-satellite tracking(SST)and optical observation of asteroid surface *** study presents a new orbiter-beacon SST scheme,in which the orbiter circumnavigates the asteroid in a low-altitude strongly-perturbed orbit,and the beacon remains in a high-altitude weakly-perturbed *** used Asteroid 433 Eros as an example,and analyzed and designed low-and high-altitude orbits for the orbiter and *** navigation measurements were precisely modeled,extended Kalman filters were devised,and observation configuration was analyzed using the Cramer-Rao lower bound(CRLB).Monte Carlo simulations were carried out to assess the effects of the orbital inclination and altitudes of the orbiter and beacon as key influencing *** simulation results showed that the proposed SST scheme was an effective solution for enhancing the autonomous navigation performance of the orbiter,particularly for improving the accuracy of gravity estimation.

关键词： asteroid exploration gravity estimation orbit determination satellite-to-satellite tracking(SST) optical observation

Evolution of inclusions in vacuum induction melting of superalloys containing 70%return material

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Journal of Iron and Steel Research International 2024年第3期31卷 719-728页

作者： Jin-guo gao shu-lei yang shu-feng yang Jing-she Li Wei Liu Meng-jing Zhao An-ren Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Metallurgical and Building Materials Business Department China International Engineering Consulting CorporationBeijing 100048China

The variation law of inclusions type and size in the vacuum induction melting process and ingot of Ni-based superalloy containing 70%return material was studied by industrial test sampling,and the mechanism of inclusions formation was analyzed with thermodynamic *** results show that there are mainly two types of composite inclusions in the vacuum induction melting of Ni-based superalloys,which are nitride-and oxide-based composite inclusions,like Al_(2)O_(3)-SiO_(2)-Cr_(2)O_(3),TiN-(Mo,Nb)C,*** type and proportion of inclusions from the center to the edge of the vacuum induction ingot did not change *** number density of inclusions from the center to the edge of the ingot varied less,and the size of inclusions became smaller from the center to the *** addition,thermodynamic calculations show that oxides(M_(2)O_(3))are present in the liquid phase and mainly contain Al,Ti,Cr,Fe and O *** nitride consists mainly of Ti and N and contains small amounts of Cr,C,Nb,and Mo *** is consistent with the results of industrial *** the temperature decreases,the precipitation phases such as M_(2)O_(3),MN,γ,MC,δ,γ'andμphases are gradually precipitated,where oxides and nitrides are present in the liquid *** contents of O and N elements are the main influencing factors for the inclusions content and precipitation temperature;when the nitrogen content is reduced to below 0.0015%,it can make MN precipitate below the liquid-phase line.

关键词： Ni-based superalloy Vacuum induction melting Return material Inclusion Thermodynamic

Asymptotic normality of error density estimator in stationary and explosive autoregressive models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 140-158页

作者： WU Shi-peng yang Wen-zhi gao Min HU shu-he School of Mathematical Sciences&School of Big Data and Statistics Anhui UniversityHefei 230601China School of Statistics Shanxi University of Finance and EconomicsTaiyuan030006China

In this paper,we consider the limit distribution of the error density function estima-tor in the rst-order autoregressive models with negatively associated and positively associated random *** mild regularity assumptions,some asymptotic normality results of the residual density estimator are obtained when the autoregressive models are stationary process and explosive *** order to illustrate these results,some simulations such as con dence intervals and mean integrated square errors are provided in this *** shows that the residual density estimator can replace the density\estimator"which contains errors.

关键词： explosive autoregressive models residual density estimator asymptotic distribution association sequence

Anti-osteosarcoma trimodal synergistic therapy using NiFe-LDH and MXene nanocomposite for enhanced biocompatibility and efficacy

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1329-1344页

作者： Yani Xu Lan yang Min Li Haozhou shu Na Jia Yunzhen gao Rongying Shi Xiaojia yang Zhirong Zhang Ling Zhang Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry West China School of PharmacySichuan UniversityChengdu 610041China Med-X Center for Materials College of Polymer Science and EngineeringSichuan UniversityChengdu 610065China

Osteosarcoma is usually resistant to immunotherapy and,thus primarily relies on surgical resection and high-dosage ***,less invasive or toxic therapies such as photothermal therapy(PTT)and chemodynamic therapy(CDT)generally failed to show satisfactory *** multimodal therapies with proper safety profiles may provide better solutions for ***,a simple nanocomposite that synergistically combines CDT,PTT,and chemotherapy for osteosarcoma treatment was *** this composite,small 2D Ni Fe-LDH flakes were processed into 3D hollow nanospheres via template methods to encapsulate 5-Fluorouracil(5-FU)with high loading *** nanospheres were then adsorbed onto larger 2D Ti3C2MXene monolayers and finally shielded by bovine serum albumin(BSA)to form 5-FU@Ni Fe-LDH/Ti3C2/BSA nanoplatforms(5NiTiB).Both in vitro and in vivo data demonstrated that the 5-FU induced chemotherapy,Ni Fe-LDH driven chemodynamic effects,and MXene-based photothermal killing collectively exhibited a synergistic“all-in-one”anti-tumor effect.5NiTiB improved tumor suppression rate from<5%by 5-FU alone to~80.1%.This nanotherapeutic platform achieved higher therapeutic efficacy with a lower agent dose,thereby minimizing side ***,the composite is simple to produce,enabling the fine-tuning of dosages to suit different ***,the platform is versatile and efficient,with potential for further development.

关键词： Osteosarcoma NiFe-LDH MXene Chemodynamic therapy Photothermal therapy Chemotherapy 5-Fluorouracil Nanocomposite

A 30-year overview of sodium-ion batteries

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Carbon Energy 2024年第6期6卷 56-98页

作者： Yun gao Hang Zhang Jian Peng Lin Li Yao Xiao Li Li yang Liu Yun Qiao shu-Lei Chou School of Environmental and Chemical Engineering Shanghai UniversityShanghaiChina College of Chemistry and Materials Engineering Wenzhou UniversityWenzhouZhejiangChina Institute for Superconducting and Electronic Materials University of WollongongWollongongNew South WalesAustralia

Sodium-ion batteries(NIBs)have emerged as a promising alternative to commercial lithium-ion batteries(LIBs)due to the similar properties of the Li and Na elements as well as the abundance and accessibility of Na *** of the current research has been focused on the half-cell system(using Na metal as the counter electrode)to evaluate the performance of the cathode/anode/*** relationship between the performance achieved in half cells and that obtained in full cells,however,has been neglected in much of this ***,the trade-off in the relationship between electrochemical performance and cost needs to be given more ***,systematic and comprehensive insights into the research status and key issues for the full-cell system need to be gained to advance its ***,this review evaluates the recent progress based on various cathodes and highlights the most significant challenges for full *** strategies have also been proposed to enhance the electrochemical performance of NIBs,including designing electrode materials,optimizing electrolytes,sodium compensation,and so ***,perspectives and outlooks are provided to guide future research on sodium-ion full cells.

关键词： commercial application electrode electrolyte sodium-ion full cell strategies

Celastrol inhibits inflammatory factors expression in glioblastoma

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Traditional Medicine Research 2024年第6期9卷 1-11页

作者： Na Qin shu-Xian yang Shi-Man gao Ting Zhu Institute of Neuroregeneration&Neurorehabilitation Department of PathophysiologySchool of Basic MedicineQingdao UniversityQingdao 266071China Department of Pharmacy Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China Women and Children’s Hospital Qingdao UniversityQingdao 266034China

Background:Glioblastoma is one of the most common primary intracranial tumors of the central nervous system in *** chemotherapy is an important component of glioblastoma treatment,its effectiveness remains *** to multiple immunosuppressive mechanisms,glioblastoma immunotherapy has not been effective in treating many patients as a result of the clinical breakthroughs in the ***,the development of cancer immunotherapy relies on the understanding of how tumors interact with the immune system and the analysis of their molecular *** study identified the key interactions between immune cells in the glioma microenvironment using RNA microarrays and single-cell ***:First,we screened differentially expressed genes in tumor and control samples from GSE29796 and GSE50161 datasets using *** differentially expressed genes were used to perform enrichment analysis and construct protein-protein interaction topological analysis to analyze the interaction between *** single-cell RNA sequencing data from the GSE162631 database,we identified immune cell types within the glioblastoma microenvironment,and validated the hub gene expression in these *** addition,based on the GEPIA and TIMER databases,hub genes were investigated and compared with immune infiltration to determine differential ***,CellChat was used to visualize the gene expression distribution and cell-to-cell communication analysis of the proteins between different types of ***:We found that monocytes/macrophages may communicate with each other in the tumor microenvironment through MIF-(CD74+CXCR4)and MIF-(CD74+CD44).In addition,our study indicated that celastrol has the ability to inhibit inflammatory factors expression by MIF/CD74 signaling pathway in U87 ***:This study improved the effectiveness of cancer immunotherapy strategies and developed new ideas for immunotherapy that can be applied to gl

关键词： glioblastoma monocytes/macrophages single-cell RNA sequencing MIF/CD74 signaling pathway celastrol

Love wave propagation in one-dimensional piezoelectric quasicrystal multilayered nanoplates with surface effects

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 619-632页

作者： Xin FENG Liaoliang KE yang gao College of Science China Agricultural UniversityBeijing 100083China School of Mechanical Engineering Tianjin UniversityTianjin 300350China

The exact solutions for the propagation of Love waves in one-dimensional(1D)hexagonal piezoelectric quasicrystal(PQC)nanoplates with surface effects are *** electro-elastic model is developed to investigate the anti-plane strain problem of Love wave *** introducing three shape functions,the wave equations and electric balance equations are decoupled into three uncorrelated *** the boundary conditions of the top surface on the covering layer,the interlayer interface,and the matrix,a dispersive equation with the influence of multi-physical field coupling is provided.A surface PQC model is developed to investigate the surface effects on the propagation behaviors of Love waves in quasicrystal(QC)multilayered structures with nanoscale thicknesses.A novel dispersion relation for the PQC structure is derived in an explicit closed form according to the non-classical mechanical and electric boundary *** examples are given to reveal the effects of the boundary conditions,stacking sequence,characteristic scale,and phason fluctuation characteristics on the dispersion curves of Love waves propagating in PQC nanoplates with surface effects.

关键词： piezoelectric quasicrystal(PQC)material multilayered plate dispersion characteristic surface effect

Novel Optimal Dispatch Method for Multiple Energy Sources in Regional Integrated Energy Systems Considering Wind Curtailment

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 2166-2173页

作者： yang gao Qian Ai Key Laboratory of Control of Power Transmission and Conversion Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China

Power-to-gas technology uses temporary surplus electricity to create either renewable hydrogen or renewable natural gas,which can then be stored in natural-gas pipelines and used when *** a result,P2G transforms conventional one-way coupling of a power/heat/natural-gas system into twoway ***,its operating characteristics makes it possible to more effectively utilize *** paper describes a new optimal dispatch model for integrated electricity/gas/heat energy *** model considers the effective use of surplus wind-energy with electricity-to-gas ***,a multi-energy network model is built,taking into account both equipment and network ***,we apply a novel two-layer optimization method,which uses P2G,to“absorb”wind *** the top-layer model is used for the dayahead dispatch of the natural-gas network containing P2G,the bottom-layer model describes the day-ahead economic dispatch of the electricity/heat system,which includes wind *** on the Karush-Kuhn-Tucher conditions of the bottom-layer model,the two-layer model is transformed into a single-layer model,and we linearize the nonlinear equation to convert the nonlinear model into a mix-integer linear programming problem,which is solvable using the General Algebraic Modeling ***,numerical case-studies are performed to evaluate the accuracy and effectiveness of the proposed method.

关键词： Multi-enery coupling power-to-gas two-layer optimization wind-power consumption

Highly anti-corrosive NiFe LDHs–NiFe alloy hybrid enables long-term stable alkaline seawater electrolysis

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Rare Metals 2024年第9期43卷 4321-4332页

作者： Jia-Hong Li Hao Chen Si-Hang You Gan-Xin yang Peng Liu Meng-Qi gao shu-Guang Chen Fei-Fei Zhang School of Materials Science and Engineering Changsha University of Science and TechnologyHunan 410114China Department of Materials Science and Engineering Faculty of EngineeringNational University of SingaporeSingapore 117576Singapore School of Materials Science and Engineering Jilin UniversityJilin 130022China

Owing to the significant potential of alkalin seawater electrolysis for converting surplus power into eco friendly hydrogen fuel,we developed bifunctional elec trodes that integrate low-crystalline NiFe LDHs and amorphous NiFe alloy on a Ni foam(NF)substrate to enhance this *** by the battery-like charac teristics of NiFe LDHs,an anti-corrosive and active oute layer of NiFe^(vac)OOH continuously forms over time in th hybrid on the anode for the oxygen evolution reaction(OER),effectively mitigating powder shedding caused by corrosion induced by multiple anions in *** while,the strong bond between the hybrid and the NF substrate maintains intact hybrid coatings to ensure a rel atively high overall conductivity of the electrodes,signif icantly reducing the negative effects of structura degradation during the OER and hydrogen evolution reaction(HER),as well as the accumulation of contami nants on the electrode *** long-term tests,thes bifunctionalhybridelectrodesmaintained stable performance,even at a high current density o500 mA·cm^(-2).The cell voltage increased by only 88 m V over 1000 h to 1.970 V during saline electrolysis and by103 mV over 500 h to 2.062 V during seawater electroly ***,this study provides valuable insights into efficient and stable seawater electrolysis using NiFe LDHs–NiFe alloy hybrids.

关键词： NiFe LDHs Bifunctional Corrosion Stability Seawater electrolysis