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High-precision Measurements of Cosmic Curvature from Gravitational Wave and Cosmic Chronometer Observations

Research in Astronomy and Astrophysics 2022年第8期22卷 198-205页

作者： Yuan He Yu Pan dong-ping Shi Jin Li Shuo Cao Wei Cheng School of Science Chongqing University of Posts and TelecommunicationsChongqing 400065China School of Electronic and Electrical Engineering Chongqing University of Arts and SciencesChongqing 402160China Department of Physics and Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China Department of Astronomy Beijing Normal UniversityBeijing 100875China

Although the spatial curvature has been measured with very high precision,it still suffers from the well-known cosmic curvature *** this paper,we use an improved method to determine the cosmic curvature,by using the simulated data of binary neutron star mergers observed by the second generation space-based DECi-hertz Interferometer Gravitational-wave Observatory(DECIGO).By applying the Hubble parameter observations of cosmic chronometers to the DECIGO standard sirens,we explore different possibilities of making measurements of the cosmic curvature referring to a distant past:one is to reconstruct the Hubble parameters through the Gaussian process without the influence of hypothetical models,and the other is deriving constraints onΩKin the framework of the non-flatΛcold dark matter *** is shown that in the improved method DECIGO could provide a reliable and stringent constraint on the cosmic curvature(ΩK=-0.007±0.016),while we could only expect the zero cosmic curvature to be established at the precision ofΔΩK=0.11 in the second model-dependent ***,our results indicate that in the framework of methodology proposed in this paper,the increasing number of well-measured standard sirens in DECIGO could significantly reduce the bias of estimations for cosmic *** a constraint is also comparable to the precision of Planck 2018 results with the newest cosmic microwave background(CMB)observations(ΔΩK≈0.018),based on the concordanceΛCDM model.

关键词： (cosmology:)cosmological parameters gravitational waves cosmology:observations

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Microstructures and properties of Al_2O_3 dispersion-strengthened copper alloys prepared through different methods

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International Journal of Minerals,Metallurgy and Materials 2016年第12期23卷 1437-1443页

作者： Zhi-qiao Yan Feng Chen Fu-xing Ye dong-ping Zhang Yi-xiang Cai Guangdong Institute of Materials and Processing Guangdong Academy of Sciences State Key Laboratory of Powder Metallurgy Central South University

Al2O3 dispersion copper alloy powder was prepared by intemal oxidation, and three consolidation methods--high-velocity compaction （HVC）, hot pressing （HP）, and hot extrusion （HE）--were used to prepare Al2O3 dispersion-strengthened copper （Cu-Al2O3） alloys. The microstructures and properties of these alloys were investigated and compared. The results show that the alloys prepared by the HP and HE methods exhibited the coarsest and finest grain sizes, respectively. The alloy prepared by the HVC method exhibited the lowest relative density （98.3% vs. 99.5% for HP and 100% for HE）, which resulted in the lowest electrical conductivity （81% IACS vs. 86% IACS for HP and 87% IACS for HE）. However, this alloy also exhibited the highest hardness （77 HRB vs. 69 HRB for HP and 70 HRB for HE）, the highest compressive strength （443 MPa vs. 386 MPa for I/P and 378 MPa for HE）, and the best hardness retention among the investigated alloys. The results illustrate that the alloy prepared by the HVC method exhibits high softening temperature and good mechanical properties at high temperatures, which imply long service life when used as spot-welding electrodes.

关键词： dispersion-strengthened alloys copper alloys alumina preparation methods microstructure properties

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Radical gastrectomy for D2 distal gastric cancer

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Chinese Journal of Cancer Research 2013年第4期25卷 468-470页

作者： ping dong Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine

Patient＇s information The patient is a 56-year-old man who visited our hospital for ＂repeated epigastric pain for more than two months.＂ Physical examination showed nearly pale appearance; abdomen was soft and no m... 详细信息

关键词： Figure Radical gastrectomy for D2 distal gastric cancer

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SYNTHESIS AND PHOTOLUMINESCENCE OF AN ANTHRACENE-CONTAINING HYPERBRANCHED POLY(ARYLENEETHYNYLENE)

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Chinese Journal of Polymer Science 2005年第6期23卷 665-669页

作者： Yong-qiang dong Zhen Li Jacky W. Y. Lam Yu-ping dong Xin-de Feng Ben-zhong Tang Department of Polymer Science and Engineering College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Department of Chemistry Center for Display Research The Hong Kong University of Science ＆ Technology Clear Water Bay Kowloon Hong Kong China

A hyperbranched poly（aryleneethynylene） containing anthracene chromophore was synthesized by palladiumcatalyzed cross-coupling reaction of 2,4,6-triiodophenyl 9-anthracenylcarboxylate with 9,9-bis[4-（2-propynyloxy）phenyl]- 9H-fluorene. The structure and properties of the polymer are characterized and evaluated by NMR, IR, UV, PL and TGA analyses. The polymer is soluble in common organic solvents, possesses high thermal stability （Td 〉 330℃）, and emits a strong blue light of 465 nm in both solution and solid states.

关键词： Hyperbranched polymer Cross-coupling Blue light emission

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Chromium Recycling from Argon-oxygen Decarburization Dust in Hot Metal Pre-dephosphorization Process

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Journal of Iron and Steel Research International 2016年第9期23卷 867-873页

作者： dong-ping ZHAN Yang-peng ZHANG Zhou-hua JIANG De-wei WANG Hui-shu ZHANG School of Metallurgy Northeastern University Metallurgical Engineering College Liaoning Institute of Science and Technology

The chromium recycling from the stainless steel dust of an argon-oxygen decarburization （AOD） furnace during a hot metal pretreatment process was investigated. Experiments at different temperatures or with different amounts of AOD dusts were carried out in a laboratory furnace equipped with MoSi2 heating elements and subsequently industrial experiments were conducted in a stainless steelmaking factory, in order to study the thermodynamic mechanism of C and Si reacted with Cr2O3 to get Cr from AOD dust. The results showed that the reaction between C and Cr2 O1 occurred below 1572.18 K. Although its reducing ability was weaker than that of Si, C enabled the Cr in Cr2O3 in the AOD dust to be recycled using the Si in the slag. By combining the AOD dust added in an earlier stage, the hot metal pretreatment slag added in a later stage could not only recycle Cr from AOD dust but also remove Si, S, and P. Higher hot metal temperatures resulted in higher Cr content and lower remained P concentration in the molten iron.

关键词： stainless steelmaking AOD dust chromium recycling hot metal pre-dephosphorization

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老年慢性病患者疼痛状况与主观预期寿命的关系：日常活动能力与抑郁的链式中介作用

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现代预防医学 2025年第2期52卷 310-314+341页

作者：张宝轩罗金萍孙嘉颖耿铭慧牟艺帆尹文强陈钟鸣马东平山东第二医科大学管理学院 “健康山东”重大社会风险预测与治理协同创新中心健康风险预警治理协同创新中心

目的探讨日常活动能力与抑郁在老年慢性病患者疼痛状况与主观预期寿命间的中介作用，为积极老龄化提供建议与参考。方法基于中国健康与养老追踪调查(CHARLS)2020年数据，选取≥60岁慢性病患者5 768名作为研究对象，运用Spearman相关... 详细信息

目的探讨日常活动能力与抑郁在老年慢性病患者疼痛状况与主观预期寿命间的中介作用，为积极老龄化提供建议与参考。方法基于中国健康与养老追踪调查(CHARLS)2020年数据，选取≥60岁慢性病患者5 768名作为研究对象，运用Spearman相关分析方法探讨疼痛、日常活动能力、抑郁和主观预期寿命之间的相关性，采用PROCESS 4.1程序Model 6构建链式中介模型。结果疼痛与日常活动能力受损、抑郁呈正相关(r=0.399,P<0.001;r=0.370,P<0.001),与主观预期寿命呈负相关(r=-0.221,P<0.001);日常活动能力与抑郁在疼痛与主观预期寿命之间的中介效应显著，简单中介效应值分别为-0.023(95%CI:-0.031～-0.016)和-0.042(95%CI:-0.049～-0.034),链式中介效应为-0.013(95%CI:-0.016～-0.010)。日常活动能力和抑郁在疼痛与主观预期寿命间的总中介效应值为-0.078,效应占比为57.78%。结论日常活动能力与抑郁在老年慢性病患者疼痛状况与主观预期寿命间存在链式中介效应。随着基层医疗卫生服务的普及，家庭医生服务团队需要提高对老年慢性病患者综合管理力度，从疼痛管理、日常活动能力干预、抑郁调节等多方面提升老年慢性病患者的主观幸福感，延长主观预期寿命。

关键词：老年人慢性病疼痛主观预期寿命链式中介

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Simulated moving bed separation of tocopherol homologues:simulation and experiments

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第5期10卷 758-766页

作者： Yu-bin LU Bao-gen SU Yi-wen YANG Qi-long REN ping-dong WU National Laboratory of Secondary Resources Chemical Engineering Zhejiang University Hangzhou 310027 China Hangzhou Zhongmei Huadong Pharmaceutical Co. Ltd. Hangzhou 310011 China

Chromatograms of tocopherol homologues were obtained by a column of analytical size (inner diameter (ID) 0.46 cm cm×10 cm) packed with silica gel. Adsorption isotherms and film mass-transfer coefficient were estimated from the chroma-tograms by using a general rate model, which considers axial dispersion, external mass-transfer and intraparticle diffusion. Based on the obtained isotherms and mass-transfer coefficient, the separation process of tocopherol homologues on simulated moving bed (SMB) was simulated using the same model. According to the simulated results, a mixture of α-, γ-, δ-tocopherols and other impurities was separated on an SMB equipment. The SMB equipment was composed of 8 columns of ID 2 cm×10 cm, with 2 columns in each section. The solid phase was silica gel, and the mobile phase was n-hexane/2-propanol (99/1 by volume). γ-and δ-tocopherols of purity greater than 98% were obtained with recovery greater than 98%. The effects of operating conditions (flow rates and switching time) on the performance of SMB were studied by both simulation and experiments. It was found that all the simulation results were quite close to the experimental results. We conclude that process development and optimization of operating conditions of SMB by simulation are feasible.

关键词： Simulated moving bed (SMB) Separation Modeling Simulation Tocopherol homologues

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Migration of harmful elements in municipal sludge under hightemperature oxidation conditions

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Journal of Iron and Steel Research International 2023年第9期30卷 1701-1713页

作者： Xiao-dong ping Hai-feng Wang Feng Wang Xin-yu Wan Zhi-wei An Jian-lei Pan State Key Laboratory of Advanced Steel Processes and Products Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China Department of Science and Technology Development China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China Production and Equipment Department Chengde Jianlong Special Steel Co.Ltd.Chengde 067200HebeiChina Technology Department Chengde Jianlong Special Steel Co.Ltd.Chengde 067200HebeiChina

Municipal sludge is produced in large amounts and is difficult to *** is the most direct and thorough treatment *** order to study the feasibility of sintering for municipal sludge treatment,the municipal sludge reforming process was studied under high-temperature oxidation *** results showed that the sludge reforming process could be divided into four stages:the precipitation and evaporation of adsorbed water,the precipitation and combustion of the volatile,the combustion of the residual volatile and solid carbon,and the decomposition of salts and the melting of *** increase in the heating rate resulted in more intense sludge combustion and improved the sludge reaction capacity and combustion *** burning at 1300℃,Si,Ca,Mg,Al,K,Na,and Cu formed new phases and entered the slag.75%of P remained in the slag.80%of the S formed SO_(2) and entered the flue *** formed gaseous chlorides like HCl upon combustion and entered the flue *** sintering is a feasible method for treating municipal sludge,care must be taken to limit the amount of P that ends up in the ore.

关键词： Municipal sludge Oxidizing atmosphere Mini-sintering Reforming process Element migration

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Seasonal Suspended Particles Distribution Patterns in Western South Yellow Sea Based on Acoustic Doppler Current Profiler Observation

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Journal of Ocean University of China 2015年第3期14卷 385-398页

作者： LI Jianchao LI Guangxue XU Jishang QIAO Lulu dong ping DING dong LIU Shidong SUN pingkuo Key Lab of Submarine Sciences & Prospecting Techniques MOE Ocean University of China College of Marine Geosciences Ocean University of China

An Acoustic Doppler Current Profiler （ADCP） observation site was set up in the Western South Yellow Sea from 2012 to 2013 to study the local suspended particle matters （SPM） distribution pattern. The SPM concentration could be semi-quantitatively represented by backscatter intensity （Sv）, converted by the echo intensity （E/） of ADCP. Results show two types of SPM in the water column： the quasi-biological SPM and quasi-mineral SPM. The quasi-biological SPM mainly exists in summer half year and is con- centrated above the thermocline. It has periodically diurnal variations with high concentration at night and low concentration in the daytime. The quasi-mineral SPM is located in lower part of the water column, with similar relation to monthly tidal current variation all year round. However, the daily quasi-mineral SPM distribution patterns vary between summer and winter half year. The sunlight is thought to be the origin factor leading to the diurnally vertical motion of the biological features, which might cause the diurnal Sv variation. Unlike in winter half year when tidal current is relatively single driving force of the monthly SPM pattern, the high speed current near the thermocline is also responsible for the concentration of quasi-mineral SPM in summer half year. The sediment input difference between summer and winter half year contribute to the varied daily variation of quasi-mineral SPM with re-suspended SPM ir~ winter and sediments from Yellow Sea Mud Area （YSMA） in summer. The seasonal variations in hydrodynamics, water structure and heavy-wind incidents are the primary factors influencing the differential seasonal SPM distribution patterns.

关键词： the South Yellow Sea backscatter intensity suspended particle matters seasonal distribution patterns diurnal periodicvariation

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Three-dimensional numerical simulation of wave interaction with perforated quasi-ellipse caisson

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Water Science and Engineering 2011年第1期4卷 46-60页

作者： Yong-xue WANG Xiao-zhong REN ping dong Guo-yu WANG State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 P. R. China Department of Civil Engineering School of Engineering Physics and Mathematics University of Dundee Dundee DD1 4HN UK

The finite difference method and the volume of fluid （VOF） method were used to develop a three-dimensional numerical model to study wave interaction with a perforated caisson. The partial cell method was adopted to solve this type of problem for the first time. The validity of the present model, with and without the presence of caisson structures, was examined by comparing the model results with experimental data. Then, the numerical model was used to investigate the effects of various wave and structure parameters on the wave force and wave runup of the perforated quasi-ellipse caisson. Compared with the solid quasi-ellipse caisson, the wave force on the perforated quasi-ellipse caisson is significantly reduced with increasing porosity of the perforated quasi-ellipse caisson. Furthermore, the perforated quasi-ellipse caisson can also reduce the wave runup, and it tends to decrease with the increase of the porosity of the perforated quasi-ellipse caisson and the relative wave height.

关键词： VOF method, partial cell method, perforated quasi-ellipse caisson, wave pressure,wave force wave runup

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