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Evaluating the Impact of Optical Axis Stability on Exoplanet Detection

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Research in Astronomy and Astrophysics 2022年第2期22卷 86-91页

作者： Dong-jie Tan Jia-cheng Liu Zi zhu Niu Liu School of Astronomy and Space Science Key Laboratory of Modern Astronomy and Astrophysics(Ministry of Education)Nanjing University163 Xianlin Avenue210023 NanjingChina

For detecting exoplanets with high precision,using the angular distance between the two stars to detect the periodic motion of the star will be a better choice.This approach can avoid importing the position error of the reference catalog in the process that uses a traditional photographic plate to derive the star position suffers.At the precision level of microarcseconds,the error caused by optical axis deviation is not negligible.In this paper,we evaluate the impact of the stability of the optical axis on the relative angular distance measurement from the aspects of theoretical analysis and numerical simulation.When the angular distance error limit of 1 microarcsecond is given,the upper limit of optical axis deviation is estimated to be 68 milliarcsecond.In addition,when limiting the deviation of the optical axis,we give the corresponding error allowance of angular distance measurement.Moreover,we also discuss the way to resolve the problem of CCD distortion and focal length change on the measurement of angular distance.The work in this paper is of guiding significance to the design of a telescope.

关键词： instrumentation:high angular resolution methods:numerical planets and satellites:detection

Construction of SnS-Mo-graphene nanosheets composite for highly reversible and stable lithium/sodium storage

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Journal of Materials Science & Technology 2022年第26期121卷 190-198页

作者： Deliang cheng Lichun Yang Renzong Hu jie Cui Jiangwen Liu Min zhu School of Materials Science and Engineering South China University of TechnologyGuangzhou 510640China Institute of Advanced Materials Jiangxi Normal UniversityNanchang 330022China Analytical and Testing Center South China University of TechnologyGuangzhou 510640China

Sn-based chalcogenides are considered as one of the most promising anode materials for lithium-ion batteries(LIBs)because of their high capacities through both conversion and alloying reactions.However,the realization of full capacities of Sn-based chalcogenides is mainly hindered by the large volume variation and inferior reversibility of conversion reaction during cycling.In present work,a new ternary Sn SMo-graphene nanosheets(Sn S-Mo-GNs)composite is fabricated by a simple and scalable plasma milling method,in which Sn S nanoparticles are tightly bonded with Mo and GNs.The Mo and GNs additives can effectively alleviate the large volume change of Sn S upon cycling,which leads to a stable electrochemical framework.Moreover,they can significantly suppress the Sn agglomeration in lithiated Sn S,which enables highly reversible conversion reaction during cycling.As anode for LIBs,the Sn S-Mo-GNs composite exhibits a high initial coulombic efficiency of 86.9%(almost complete reversibility of Sn S,~97.3%),high cyclic coulombic efficiency after initial three cycles(>99.5%),and long lifespan(up to 600 cycles).Moreover,it also demonstrates superior electrochemical performance for sodium storage.Thus,this work demonstrates a potential anode for batteries application and provides a viable strategy to obtain highly reversible and stable anodes for lithium/sodium storage.

关键词： SnS nanoparticle Mo metal Graphene nanosheets Reversibility Anode

Calcitonin gene-related peptide inhibits neuronal apoptosis in heatstroke rats via PKA/p-CREB pathway

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Chinese Journal of Traumatology 2024年第1期27卷 18-26页

作者： jie zhu Ya-Hong Chen Jing-Jing Ji cheng-Xiang Lu Zhi-Feng Liu Department of Pediatric General Hospital of Southern Theater Command of PLAGuangzhou510010China Department of Medical Intensive Care Unit General Hospital of Southern Theater Command of PLAGuangzhou510010China Department of Intensive Care Unit Zhongshan Hospital Xiamen UniversityXiamenFujian province361004China

Purpose:The incidence of heatstroke(HS)is not particularly high;however,once it occurs,the consequences are serious.It is reported that calcitonin gene-related peptide(CGRP)is protective against brain injury in HS rats,but detailed molecular mechanisms need to be further investigated.In this study,we further explored whether CGRP inhibited neuronal apoptosis in HS rats via protein kinase A(PKA)/p-cAMP response element-binding protein(p-CREB)pathway.Methods:We established a HS rat model in a pre-warmed artificial climate chamber with a temperature of(35.5±0.5)℃and a relative humidity of 60%±5%.Heatstress was stopped once core body temperature reaches above 41℃.A total of 25 rats were randomly divided into 5 groups with 5 animals each:control group,HS group,HS+CGRP group,HS+CGRP antagonist(CGRP8-37)group,and HS+CGRP+PKA/p-CREB pathway blocker(H89)group.A bolus injection of CGRP was administered to each rat in HS+CGRP group,CGRP8-37(antagonist of CGRP)in HS+CGRP8-37 group,and CGRP with H89 in HS+CGRP+H89 group.Electroencephalograms were recorded and the serum concentration of S100B,neuron-specific enolase(NSE),neuron apoptosis,activated caspase-3 and CGRP expression,as well as pathological morphology of brain tissue were detected at 2 h,6 h,and 24 h after HSin vivo.The expression of PKA,p-CREB,and Bcl-2 in rat neurons were also detected at 2 h after HSin vitro.Exogenous CGRP,CGRP8-37,or H89 were used to determine whether CGRP plays a protective role in brain injury via PKA/p-CREB pathway.The unpairedt-test was used between the 2 samples,and the mean±SD was used for multiple samples.Double-tailedp<0.05 was considered statistically significant.Results:Electroencephalogram showed significant alteration ofθ(54.50±11.51vs.31.30±8.71,F=6.790,p=0.005)andαwave(16.60±3.21vs.35.40±11.28,F=4.549,p=0.020)in HS group compared to the control group 2 h after HS.The results of triphosphate gap terminal labeling(TUNEL)showed that the neuronal apoptosis of HS rats was increased in the cortex(9.67±3.16vs.1.80±1.10,F=11.002,p=0.001)and

关键词： Heatstroke Calcitonin gene-related peptide Brain injury Apoptosis

Some remarks on Wente's inequality and the Lorentz-Sobolev space

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Applied Mathematics(A Journal of Chinese Universities) 2016年第3期31卷 355-361页

作者： zhu Xiang-rong CHEN jie-cheng Department of Mathematica Zhejiang Normal University

In this note we consider Wente＇s type inequality on the Lorentz-Sobolev space. If f∈L^p1,q1（Rn）,G∈L^p2,q2 （Rn） and div G ≡ 0 in the sense of distribution where 1/p1＋1/p2=1/q ＋1/q2=1,1〈p1,p2〈∞, it is known that G. f belongs to the Hardy space H1 and furthermore ‖G· f‖N1≤C‖ f‖Lp1,q1（R2）‖G‖Lp2,q2（R2）Reader can see [9] Section 4 Here we give a new proof of this result. Our proof depends on an estimate of a maximal operator on the Lorentz space which is of some independent interest. Finally, we use this inequality to get a generalisation of Bethuel＇s inequality.

关键词： Lorentz space Wente type inequality Hardy space

Hybridized triboelectric-electromagnetic nanogenerators and solar cell for energy harvesting and wireless power transmission

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Nano Research 2022年第3期15卷 2069-2076页

作者： Yandong Chen Yang jie Jiaqing zhu Qixin Lu Yu cheng Xia Cao Zhong Lin Wang Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 100083China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China Research Center for Bioengineering and Sensing Technology Beijing Key Laboratory for Bioengineering and Sensing TechnologySchool of Chemistry and Biological EngineeringBeijing Municipal Key Laboratory of New Energy Materials and Technologiesand Center for Green InnovationSchool of Mathematics and PhysicsUniversity of Science and Technology BeijingBeijing 100083China Center on Nanoenergy Research School of Physical Science and Technology Guangxi UniversityNanning 530004China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA30332-0245USA

Energy harvesting and power transmission is a signiﬁcant challenge for the self-powered technologies towards mobile electronic devices.Here,we propose a hybridized energy harvester to complement each other's strengths for simultaneously scavenging multiple types of energy and then wirelessly transmit the power.The harvester consists of electromagnetic-triboelectric nanogenerator units for collecting rotational energy and a commercial water-proof flexible solar cell.At a rotation rate of 500 rpm,the output current of electromagnetic-triboelectric nanogenerator units can reach about 630 mA through energy management.Moreover,the power harvested by hybridized energy harvester can be wirelessly transmitted up to a distance of about 100 cm in real time to charge mobile phone,anemometer,and hygrometer based on self-resonant coils.The hybridized energy harvester with wireless power transmission has potential applications in large-scale energy collection,long-distance wireless power transmission and sustainably driving mobile electronic devices.

关键词： triboelectric nanogenerator electromagnetic generator solar cell hybridized energy harvester

Evolution of interfacial heat transfer,contact behavior and microstructure during sub-rapid solidification of molten steel with different hydrogen contents

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Journal of Iron and Steel Research(International) 2024年第1期31卷 215-223页

作者： cheng Lu Wan-lin Wang Chen-yang zhu jie Zeng Xin-yuan Liu Hua-long Li School of Metallurgy and Environment Central South UniversityChangsha410083HunanChina National Center for International Research of Clean Metallurgy Central South UniversityChangsha410083HunanChina Institute of Research of Iron and Steel ShasteelZhangjiagang215625JiangsuChina

Typical Q235 low-carbon steel samples with different hydrogen contents(0.0004,0.0008,and 0.0013 wt.%)were prepared by adjusting the environment humidity and moisture.The effects of hydrogen on interfacial heat transfer,contact behavior,and microstructure evolution were investigated using a novel droplet solidification technique.The results revealed that when the hydrogen content increases from 0.0004 to 0.0013 wt.%,the maximum heat flux between the molten steel and cooling substrate decreases from 8.01 to 6.19 MW/m^(2),and the total heat removed in the initial 2 s reduces from 10.30 to 8.27 MJ/m^(2).Moreover,the final contact angle between the molten steel and substrate increases from 103.741°to 113.697°,and the number of pores on the droplet bottom surface increases significantly from 21 to 210 with the increase in hydrogen.The surface roughness of the droplet bottom surface increases from 20.902 to 49.181 pm.In addition,the average grain size of the droplet increases from 14.778 to 33.548 pm with the increase in the hydrogen content.The interfacial contact condition becomes worse due to the escape of hydrogen from the steel matrix during the cooling process,which leads to the reduction in the interfacial heat transfer and the increase in the grain size.

关键词： Strip casting Hydrogen content Interfacial heat transfer behavior Contact behavior Microstructure evolution

Elliptical distortion of the Milky Way＇s rotation traced by high-mass star-forming regions

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Research in Astronomy and Astrophysics 2017年第11期17卷 85-94页

作者： Ping-jie Ding Zi zhu Jia-cheng Liu School of Astronomy and Space Science Nanjing University Nanjing 210023 China Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education Nanjing 210023 China

The gravitational potential of the Milky Way is non-axisymmetric, caused by a bar or triaxial halo, which dominates elliptical rotation of the Milky Way. Employing a likelihood analysis, we exploit the astrometric data of masers thoroughly and constrain the elliptical rotation of the Galaxy. Masers in high-mass star-forming regions, observed by VLBA, are more distant tracers than stars observed in the optical bandpass, and thus are more appropriate for studying the global feature of the Milky Way＇s rotation. A clear elliptical potential of the Milky Way is detected, with an ellipticity of ε0-0.09 at the Sun, and the ellipticity increases towards the outer disk. The minor axis of the elliptical potential （the major axis of the rotation orbit） is found to be near the Sun with a displacement of -32°. Based on the rotation model assumed for an elliptical potential, we also make a kinematical calibration of the Galactocentric distance of the Sun, which gives R0 = 7.63±0.34 kpc.

关键词： astrometry -- Galaxy： fundamental parameters -- Galaxy： kinematics and dynamics --methods： data analysis

Spatial variation in bigeye tuna Thunnus obesus size at sexual maturity in the eastern Pacific Ocean

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Aquaculture and Fisheries 2023年第5期8卷 572-578页

作者： Hongji Huang cheng Zhou Liuxiong Xu Jiangfeng zhu Xuefang Wang jie Cao College of Marine Sciences Shanghai Ocean University999 Huchenghuan RoadLingang New DistrictShanghai201306PR China National Engineering Research Center for Oceanic Fisheries Shanghai201306China Department of Applied Ecology Center for Marine Sciences and TechnologyNorth Carolina State UniversityMorehead CityNC28557USA

Understanding the reproductive characteristics of a species is of crucial for accurate stock assessment and management plans to ensure sustainable fisheries.In this study,the size at 50%sexual maturity(L50)parameters in different bio-ecological provinces were estimated for bigeye tuna,Thunnus obesus,sampled from the Eastern Pacific Ocean tuna fisheries-dependent survey from 2013 to 2019.The overall sex ratio of the catch during the sampling differed significantly from 1:1.Bigeye tuna exhibit sexual dimorphism in the growth of males and females,with a clear shift in predominance from female to male with increasing sizes.In the North Pacific Sub-tropical Gyre(east)(NPST-east),North Pacific Tropical Gyre(NPTG),Pacific North Equatorial Countercurrent(PNEC),and Pacific Equatorial Divergence(PEQD),females(meals)reached sexual maturity round 102 cm(106 cm),106 cm(100 cm),125 cm(110 cm),and 113 cm(110 cm),respectively,the estimated L50 of bigeye tuna was 124.08 cm,121.97 cm,139.92 cm and 132.45 cm,respectively.The degree of populations mixing between equatorial(PNEC and PEQD)and high-latitude regions(NPST-east and NPTG)is extremely small,but it is reasonably high between the NPST-east and NPTG or PNEC and PEQD.These parameters were significantly different,suggesting the occurrence of a spatial difference in the size-at-maturity of bigeye tuna between these bio-ecological provinces.The findings of this study provide the key information for understanding the life history of bigeye tuna in the Eastern Pacific Ocean and will contribute to the conservation and sustainable yield of this species.

关键词： Eastern Pacific ocean Bigeye tuna Sexual maturity Mixed-effects model

Artificial intelligence-aided discovery of prolyl hydroxylase 2 inhibitors to stabilize hypoxia inducible factor-1α and promote angiogenesis

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中国化学快报：英文版 2023年第2期34卷 412-415页

作者： Jianzhong zhu cheng Chen jie Dong Shasha cheng Guodong Li Chunming Wang Defang Ouyang Chung-Hang Leung Ligen Lin State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao 999078China Xiangya School of Pharmaceutical Science Central South UniversityChangsha 410083China

From ZINC database with a total of 1.8 million small molecules, four compounds are identified as prolyl hydroxylase 2 inhibitors through a virtual screening workflow that sequentially incorporates machine learning, molecular docking, and molecular dynamics. Among them, compound 103,(E)-5-(5-((2-(1Htetrazol-5-yl)hydrazineylidene)methyl)furan-2-yl)isoindoline-1,3-dione, promotes the migration and capillary tube formation capacity of human umbilical vein endothelial cells through enhancing the stability of hypoxia inducible factor-1α and increasing the level of vascular endothelial growth factor.

关键词： Machine learning Virtual screening PHD2 Angiogenesis Wound healing