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Synergy between CSST galaxy survey and gravitational-wave observation: Inferring the Hubble constant from dark standard sirens

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 7-19页

作者： Ji-Yu Song ling-Feng Wang Yichao Li Ze-Wei zhao Jing-Fei Zhang Wen zhao Xin Zhang Key Laboratory of Cosmology and Astrophysics(Liaoning)&College of Sciences Northeastern UniversityShenyang 110819China CAS Key Laboratory for Researches in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaChinese Academy of SciencesHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityShenyang 110819China Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern Universty Shenyang 110819China

Gravitational waves(GWs) from compact binary coalescences encode the absolute luminosity distances of GW sources. Once the redshifts of GW sources are known, one can use the distance-redshift relation to constrain cosmological parameters. One way to obtain the redshifts is to localize GW sources by GW observations and then use galaxy catalogs to determine redshifts from a statistical analysis of redshift information of the potential host galaxies, commonly referred to as the dark siren method. The third-generation(3G) GW detectors are planned to work in the 2030s and will observe numerous compact binary *** these GW events as dark sirens requires high-quality galaxy catalogs from future sky survey projects. The China Space Station Telescope(CSST) will be launched in 2024 and will observe billions of galaxies within a 17500 deg^(2) survey area with redshift up to z ~ 4, providing photometric and spectroscopic galaxy catalogs. In this work, we simulate the CSST galaxy catalogs and the 5-year GW data from the 3G GW detectors and combine them to infer the Hubble constant(H_(0)). Our results show that the measurement precision of H0could reach the sub-percent level, meeting the standard of precision cosmology. We conclude that the synergy between CSST and the 3G GW detectors is of great significance in measuring the Hubble constant.

关键词： CSST galaxy survey galaxy catalogs gravitational waves dark sirens the Hubble constant

Analytical solution for the effective elastic properties of rocks with the tilted penny-shaped cracks in the transversely isotropic background

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Petroleum Science 2024年第1期21卷 221-243页

作者： Zheng-Qian Ma Xing-yao Yin zhao-Yun Zong Yuan-Yuan Tan ya-Ming yang National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266200ShandongChina

Seismic prediction of cracks is of great significance in many disciplines,for which the rock physics model is ***,up to now,multitudinous analytical models focus primarily on the cracked rock with the isotropic background,while the explicit model for the cracked rock with the anisotropic background is rarely investigated in spite of such case being often encountered in the ***,we first studied dependences of the crack opening displacement tensors on the crack dip angle in the coordinate systems formed by symmetry planes of the crack and the background anisotropy,respectively,by forty groups of numerical *** on the conclusion from the experiments,the analytical solution was derived for the effective elastic properties of the rock with the inclined penny-shaped cracks in the transversely isotropic ***,we comprehensively analyzed,according to the developed model,effects of the crack dip angle,background anisotropy,filling fluid and crack density on the effective elastic properties of the cracked *** analysis results indicate that the dip angle and background anisotropy can significantly either enhance or weaken the anisotropy degrees of the P-and SH-wave velocities,whereas they have relatively small effects on the SV-wave velocity ***,the filling fluid can increase the stiffness coefficients related to the compressional modulus by reducing crack compliance parameters,while its effects on shear coefficients depend on the crack dip *** increasing crack density reduces velocities of the dry rock,and decreasing rates of the velocities are affected by the crack dip *** comparing with exact numerical results and experimental data,it was demonstrated that the proposed model can achieve high-precision estimations of stiffness ***,the assumption of the weakly anisotropic background results in the consistency between the proposed model and Hudson's published theory for the or

关键词： Effective elastic property Tilted crack Transverse isotropy Analytical solution Crack opening displacement

Characteristics and distribution of microstructures in high pressure die cast alloys with X-ray microtomography:A review

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China Foundry 2024年第5期21卷 427-444页

作者： Hai-dong zhao Xue-ling Wang Qian Wan Wen-hui Bai Fei Liu School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China

Al and Mg alloy high pressure die castings(HPDC)are increasingly used in automotive *** microstructures in the castings have decisive effect on the casting mechanical properties,in which the microstructure characteristics are fundamental for the investigation of the microstructure-property *** the past decade,the microstructure characteristics of HPDC Al and Mg alloys,especially micro-pores andα-Fe,have been investigated from two-dimensional(2D)to threedimensional with X-ray micro-computed tomography(μ-CT).This paper provides an overview of the current understanding regarding the 3D characteristics and formation mechanisms of microstructures in HPDC alloys,their spatial distributions,and the impact on mechanical ***,it outlines future research directions for the formation and control of heterogeneous microstructures in HPDC alloys.

关键词： high pressure die casting microstructure three-dimensional characteristics distribution Al and Mg alloys

Hourly land surface temperature retrieval over the Tibetan Plateau using Geo-LightGBM framework: Fusion of Himawari-8 satellite, ERA5 and site observations

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Advances in Climate Change Research 2024年第4期15卷 623-635页

作者： zhao-Hua LIU Shan-Shan WENG zhao-Liang ZENG Ming-Hu DING ya-Qiang WANG Zhehao LIANG Civil and Surveying&Mapping Engineering Jiangxi University of Science and TechnologyGanzhou 341000China State Key Laboratory of Severe Weather Chinese Academy of Meteoroogical Sciences Beijing 100081China Space Geodesy and Geoinformation Technical Unviersity of BerlinBerlin 10623Germany

The Tibetan Plateau(TP)is highly sensitive to even minor fluctuations in land surface temperature(LST),which can result in permafrost melting and degradation of alpine grasslands,leading to serious ecological ***,it is crucial to have high-temporal-resolution and seamless hourly estimating and monitoring of LST for a better understanding of climate change on the ***,we employed Himawari-8 satellite,Digital Elevation Model(DEM),ERA5 reanalysis and meteorological station observations data to develop a new LightGBM framework(called Geo-LightGBM)for estimating LST on the TP,and then analyzed the spatiotemporal variations of those ***-LightGBM demonstrated excellent LST estimation accuracy,with an R2(coefficient of determination)of 0.971,RMSE(root-mean-square error)of 2.479℃,and MAE(mean absolute error)of 1.510℃.The estimated LST values for the year 2020 agreed well with observed values,with remarkable differences in hourly LST ***,the estimated LST was more accurate than that from ***,there were two high LST centers,located in the yarlung Zangbo River Basin and the Qaidam Basin,and a low LST center located in the central *** SHAP(SHapley Additive exPlanations)and correlation analyses revealed DSCS(the mean ground downward shortwave radiation under clear-sky conditions)to be the most importantly input variable for estimating *** dummy variables(e.g.,longitude,latitude,DEM)were also found to be crucial for model accuracy *** findings indicate the potential for constructing a high-precision and seamless 24-h LST real-time retrieval and monitoring platform for the TP by combining satellite and China's independently developed CLDAS(China Land Data Assimilation System)data in future.

关键词： Tibetan Plateau Himawari-8 ERA5 Land surface temperature Geo-LightGBM

Phosphotungstic acid immobilized on amino-functionalized TS-1 zeolite as a solid acid catalyst for the synthesis of tributyl citrate

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Chinese Journal of Chemical Engineering 2024年第6期70卷 199-210页

作者： Pei Li Bianfang Shi Junyao Shen Ran Cui Wenze Guo ling zhao Zhenhao Xi State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

The amino-functionalization of TS-1 zeolite followed by immobilization of phosphotungstic acid(HPW)was presented to prepare a strong solid acid catalyst for the synthesis of bio-based tributyl citrate from the esterification of citric acid and n-butanol.γ-Aminopropyltriethoxysilane(APTES)was first grafted on the TS-1 zeolite via the condensation reactions with surface hydroxyl groups,and subsequently the HPW was immobilized via the reaction between the amino groups and the protons from HPW-forming strong ionic *** Keggin structure of HPW and MFI topology of TS-1 zeolite were well maintained after the *** amino-functionalization generated abundant uniformly distributed active sites on TS-1 for HPW immobilization,which promoted the dispersity,abundance,as well as the stability of the acid *** tetrahedrally coordinated framework titanium and non-framework titania behaved as weak Lewis acid sites,and the protons from the immobilized HPW acted as the moderate or strong Brønsted acid *** optimized TBC yield of 96.2%(mol)with a conversion of-COOH of 98.1%(mol)was achieved at 150℃for 6 h over the HPW immobilized on amino-functionalized *** catalyst exhibited good stability after four consecutive reaction runs,where the activity leveled off at still a relatively high level after somewhat deactivation possibly caused by the leaching of a small portion of weakly anchored APTES or HPW.

关键词： Amino-functionalization Phosphotungstic acid TS-1 zeolite Esterification Tributyl citrate

Ginsenoside Rd Induces Differentiation of Myeloid Leukemia Cells via Regulating ERK/GSK-3βSignaling Pathway

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Chinese Journal of Integrative Medicine 2024年第7期30卷 588-599页

作者： JIANG Yu-xia zhao yan-na YU Xiao-ling YIN Li-ming Department of Hematology Tongde Hospital of Zhejiang ProvinceHangzhou310012China Institute of Hematology Research the First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine)Hangzhou310006China

Objective To investigate the role of ginsenoside Rd(GRd)in acute myeloid leukemia(AML)cell *** AML cells were treated with GRd(25,50,100 and 200µg/mL),retinoic acid(RA,0.1g/L)and PD98059(20 mg/mL)for 72 h,cell survival was detected by methylthiazolyldiphenyl-tetrazolium bromide and colony formation assays,and cell cycle was detected by flow *** morphology and differentiation were observed by Wright-Giemsa staining,peroxidase chemical staining and cellular immunochemistry assay,*** protein expression levels of GATA binding protein 1(GATA-1),purine rich Box-1(PU.1),phosphorylated-extracellular signal-related kinase(p-ERK),ERK,phosphorylated-glycogen synthase kinase-3β(p-GSK3β),GSK3βand signal transducer and activator of transcription 1(STAT1)were detected by Western ***-six mice were randomly divided into 3 groups using a random number table:model control group(non-treated),GRd group[treated with 200 mg/(kg·d)GRd]and homoharringtonine(HTT)group[treated with 1 mg/(kg·d)HTT].A tumor-bearing nude mouse model was established,and tumor weight and volume were *** of subcutaneous tumor tissue were observed after hematoxylin and eosin ***1 and GATA-1 expressions were detected by immunohistochemical *** The cell survival was inhibited by GRd in a dose-dependent manner and GRd caused G0/G1 cell arrest(p<0.05).GRd treatment induced leukemia cell differentiation,showing increased expressions of peroxidase and specific proteins concerning erythrogenic or granulocytic differentiation(p<0.05).GRd treatment elicited upregulation of p-ERK,p-GSK-3βand STAT1 expressions in cells,and reversed the effects of PD98059 on inhibiting the expressions of peroxidase,GATA-1 and PU.1(P<0.05).After GRd treatment,tumor weight and volume of mice were decreased,and tumor cells underwent massive apoptosis and necrosis(P<0.05).WT1 level was decreased,and GATA-1 level was significantly increased in subcutaneous tumor ti

关键词： ginsenoside Rd myeloid leukemia survival differentiation extracellular signal-related kinase signaling pathway

Chemoselective and Living/Controlled Polymerization of Alkenyl Methacrylates by the Phosphonium Ylide/Organoaluminum Lewis Pairs

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Chinese Journal of Polymer Science 2024年第2期42卷 159-167,I0005页

作者： Zhi-Kang Chen Wu-Chao zhao Yi-ling zhao Cong-Lei Liu Liu-Yin Jiang Yue-Tao Zhang Hong-Ping Zhu State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012China

Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been *** P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were *** the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy *** pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)*** thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.

关键词： Phosphonium ylide Alkenyl methacrylate Chemoselectivity Living/controlled polymerization Post-functionalization

Efficient spectral single-pixel imaging via Morton frequency-domain scanning [Invited]

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Chinese Optics Letters 2024年第6期22卷 8-14页

作者： Zi-Dong zhao zhao-Hua yang Zhi-Hao zhao ling-An Wu Yuan-Jin Yu School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Automation MIIT Key Laboratory of Complex-field Intelligent SensingBeijing Institute of TechnologyBeijing 100081China yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing 314019China

Single-pixel imaging (SPI) captures two-dimensional images utilizing a sequence of modulation patterns and measurements recorded by a single-pixel detector. However, the sequential measurement of a scene is time-consuming, especially for high-spatial-resolution imaging. Furthermore, for spectral SPI, the enormous data storage and processing time requirements substantially diminish imaging efficiency. To reduce the required number of patterns, we propose a strategy by optimizing a Hadamard pattern sequence via Morton frequency domain scanning to enhance the quality of a reconstructed spectral cube at low sampling rates. Additionally, we expedite spectral cube reconstruction, eliminating the necessity for a large Hadamard matrix. We demonstrate the effectiveness of our approach through both simulation and experiment,achieving sub-Nyquist sampling of a three-dimensional spectral cube with a spatial resolution of 256×256 pixels and181 spectral bands and a reduction in reconstruction time by four orders of magnitude. Consequently, our method offers an efficient solution for compressed spectral imaging.

关键词： single-pixel imaging spectral imaging optimized Hadamard basis

Enhanced vision-transformer integrating with semi-supervised transfer learning for state of health and remaining useful life estimation of lithium-ion batteries

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Energy and AI

Energy and AI 2024年第3期17卷 380-396页

作者： ya-Xiong Wang Shangyu zhao Shiquan Wang Kai Ou Jiujun Zhang School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350108China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China

The state of health(SOH)and remaining useful life(RUL)of lithium-ion batteries are crucial for health management and ***,most data-driven estimation methods heavily rely on scarce labeled data,while traditional transfer learning faces challenges in handling domain shifts across various battery *** paper proposes an enhanced vision-transformer integrating with semi-supervised transfer learning for SOH and RUL estimation of lithium-ion batteries.A depth-wise separable convolutional vision-transformer is developed to extract local aging details with depth-wise convolutions and establishes global dependencies between aging information using multi-head *** mean discrepancy is employed to initially reduce the distribution difference between the source and target domains,providing a superior starting point for fine-tuning the target domain ***,the abundant aging data of the same type as the target battery are labeled through semi-supervised learning,compensating for the source model's limitations in capturing target battery aging *** regularization incorporates the cross-entropy between predictions with and without adversarial perturbations into the gradient backpropagation of the overall *** particular,across the experimental groups 13–15 for different types of batteries,the root mean square error of SOH estimation was less than 0.66%,and the mean relative error of RUL estimation was 3.86%.Leveraging extensive unlabeled aging data,the proposed method could achieve accurate estimation of SOH and RUL.

关键词： State of health(S0H) Remaining useful life(RUL) Depth-wise separable convolutional vision-transformer Transfer learning Maximum mean discrepancy Semi supervised learning