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New evidence for lack of CMB power on large scales

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 567-570页

作者： liu hao1 & {2. {2.1,2.3 1 key laboratory of particle astrophysics, institute of high energy physics, chinese academy of sciences, beijing 100049, china 2.Department of {12. & Center for astrophysics, Tsinghua University, beijing 100084, china 3 Department of Engineering {12. & Center for astrophysics, Tsinghua University, beijing 100084, china 1. key laboratory of {2. astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China2. Department of Physics & Center for Astrophysics Tsinghua University Beijing 100084 China3. Department of Engineering Physics & Center for Astrophysics Tsinghua University Beijing 100084 China

A digitalized temperature map is recovered from the first light sky survey image published by the Planck team, from which an angular power spectrum of the cosmic microwave background (CMB) is derived. The amplitudes of the low multipoles (low-l) measured from the preliminary Planck power spectrum are significantly lower than those reported by the WMAP team. Possible systematical effects are far from enough to explain the observed low-l differences.

关键词： cosmology cosmic microwave background data analysis

Inconsistency between WMAP data and released map

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chinese Science Bulletin 2010年第10期55卷 907-909页

作者： liu hao1 & {2. {2.1,2.3 1 key laboratory of particle astrophysics,institute of high energy physics,chinese academy of sciences,beijing 100049,china 2.Department of {12. & Center for astrophysics,Tsinghua University,beijing 100084,china 3 Department of Engineering {12. & Center for astrophysics,Tsinghua University,beijing 100084,china key laboratory of {2. astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of physics & Center for astrophysics Tsinghua University Beijing China Department of Engineering physics & Center for astrophysics Tsinghua University Beijing China

A remarkable inconsistency between the calibrated differential time-ordered data (TOD) of the Wilkinson Microwave Anisotropy Probe (WMAP) mission,which is the input for map-making,and the cosmic microwave background (CMB) temperature maps published by the WMAP team is revealed,indicating that there must exist a serious problem in the map making routine of the WMAP *** inconsistency is easy to be confirmed without the use of WMAP map-making *** view of the importance of this issue for cosmology study,we invite readers to check it by themselves.

关键词：威尔金森微波各向异性探测器 WMAP 地图制作宇宙微波背景有序数据制作软件 TOD CMB

Implementation of a particle-in-cell method for the energy solver in 3D spherical geodynamic mode{2.ng

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Earth and Planetary physics 2024年第3期8卷 549-563页

作者： hao Dong ZeBin Cao liJun {2. YanChong li SanZhong li liMing Dai XinYu li Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Laboratory of Submarine Geosciences and Prospecting TechniquesMinistry of Education and College of Marine GeosciencesOcean University of ChinaQingdao 266100China State key laboratory of {2.thospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China laboratory for Marine Geology Laoshan LaboratoryQingdao 266237China Department of Earth Science&Environmental Change University of Illinois at Urbana-ChampaignUrbanaIL 61801USA laboratory of Seismology and physics of Earth’s Interior School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

The thermal evolution of the Earth’s interior and its dynamic effects are the focus of Earth ***,the commonly adopted grid-based temperature solver is usually prone to numerical oscillations,especially in the presence of sharp thermal gradients,such as when modeling subducting slabs and rising *** phenomenon prohibits the correct representation of thermal evolution and may cause incorrect implications of geodynamic *** examining several approaches for removing these numerical oscillations,we show that the Lagrangian method provides an ideal way to solve this *** this study,we propose a {2.-in-cell method as a strategy for improving the solution to the energy equation and demonstrate its effectiveness in both one-dimensional and three-dimensional thermal problems,as well as in a global spherical simulation with data *** have implemented this method in the open-source finite-element code CitcomS,which features a spherical coordinate system,distributed memory parallel computing,and data assimilation algorithms.

关键词： numerical oscillation overshooting and undershooting particle-in-cell method three-dimensional spherical geodynamic modeling energy solver finite element method

Normalized glandular dose coefficients for digital breast tomosynthesis using detailed chinese breast models

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Nuclear Science and Techniques 2024年第5期35卷 42-59页

作者： Jia-hao Wang Rui Qiu An-Kang Hu Ye-Qi liu Zhen Wu Hui Zhang Jun-{2. {2. Department of Engineering physics Tsinghua UniversityBeijing 100084China key laboratory of {2. and Radiation Imaging Ministry of EducationTsinghua UniversityBeijing 100084China Joint institute of Tsinghua University Nuctech Company Limited BeijingBeijing 100084China

The rise in breast cancer diagnoses among chinese women has necessitated the use of X-ray breast screening,which carries a radiation *** study aimed to provide a dosimetry protocol for the chinese female population to replace the traditional standard that uti{2.zes simp{2.fied breast models,for the accurate estimation of the mean glandular dose of a patient undergoing digital breast tomosynthesis(DBT).The first set of detailed chinese female breast models and representative breast parameters was *** backscatter radiation and computational efficiency,we improved the combination of these models and the chinese reference adult female whole-body voxel *** acquisition for four commercial DBT systems that are widely employed in china was simulated using the Monte Carlo method to obtain the norma{2.zed glandular dose coefficients of DBT(D_(gN)^(DBT))and the glandular depth dose(D_(g)^(dep)(z))for different breast characteristics and X-ray *** calculated a series of D_(gN)^(DBT) values for breasts with different percentage mass glandularities(5%,2.%,50%,75%,and 100%)and compressed breast thicknesses(2.3,4,5,6,and 7 cm)at various tube potentials(2.,2.,30,32.35,and 49 kV)and target/filter combinations(W/Rh,W/Al,Mo/Mo,Rh/Rh,and Rh/Ag).The parameter dependence of the breast characteristics and beam conditions on D_(gN)^(DBT) in detailed breast models was *** D_(gN)^(DBT) results were 14.6-51.0%lower than those of the traditional dosimetry standard in *** difference in D_(gN)^(DBT) was mainly due to a decrease in the depth of the main energy deposition area caused by the glandular distribution along the depth *** results obtained in this study may be used to improve breast dosimetry in china and provide more detailed information on risk assessment during DBT.

关键词： Digital breast tomosynthesis Normalized glandular dose coefficients Detailed breast model Monte Carlo simulation

Effect of coral sand on the mechanical properties and hydration mechanism of magnesium potassium phosphate cement mortar

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Journal of Zhejiang University-Science A(Applied physics & Engineering) 2024年第2期25卷 116-129页

作者： hao liu Huamei YANG Houzhen WEI Jining YU Qingshan MENG Rongtao YAN College of Civil Engineering and Architecture Guilin University of TechnologyGuilin541004China Guangxi key laboratory of Geomechanics and Geotechnical Engineering Guilin University of TechnologyGuilin541004China State key laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China School of Intelligent Construction Wuchang University of TechnologyWuhan430002China Hydraulic Concrete institute China Three Gorges CorporationBeijing100038China The First Railway Survey and Design institute Group Corporation Xi’an710043China

Damaged structures on coral islands have been spalling and cracking due to the dual corrosion of tides and *** ensure easy access to aggregate materials,magnesium potassium phosphate cement(MKPC)and coral sand(CS)are mixed to repair damaged structures on coral ***,CS is significantly different from land-sourced sand in mineral composition,particle morphology,and *** has a substantial impact on the hydration characteristics and macroscopic properties of MKPC ***,in this study we investigated the compressive strength,interfacial mechanical properties,and corrosion resistance of MKPC CS *** in the morphology,microstructure,and relative contents of hydration products were revealed by scanning electron microscope-{2. dispersive spectrometer(SEM-EDS)and X-ray diffraction(XRD).The results indicated that the compressive strength increased linearly with the interfacial micro-hardness,and then stabilized after long-term immersion in pure water and Na2.O4 solution,showing excellent corrosion *** with MKPC river sand(RS)mortar,the hydration products of CS mortar were an intermediate product 6KPO2.8H2. with a relative content of 3.9%at 1 h and 4.1%at 12.*** hydration product MgKPO_(4)·6H_(2.O increased rapidly after 7-d curing,with an increased growth rate of 1100%.Our results showed that CS promoted the nucleation and formation of hydration products of MKPC,resulting in better crystallinity,tighter overlapping,and a denser interfacial transition *** results of this study provide technical support for applying MKPC mortar as a rapid repair material for damaged structures on coral islands.

关键词： Magnesium potassium phosphate cement(MKPC) Coral sand(CS) Mechanical properties Corrosion resistance Hydration mechanism

Alternative technology for the recovery of butyl acetate with low concentration:high capacity adsorbent and high efficiency adsorption

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Green Chemical Engineering 2024年第2期5卷 236-244页

作者： Chi Ma lihong Zhao Zhengxin Mao hao Su Qingfen liu CAS key laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

Industrial pharmaceutical wastewater usually contains butyl acetate(BA)with a concentration of 1 wt%-7 wt%,and the traditional method for BA recovery is distillation with high energy *** method is developed to recover BA with low concentration for the high efficiency and low energy *** polar polyacrylate resins with macroporous structure of 2.3.1 nm and average particle size of about 52..5μm are successfully synthesized by suspension polymerization and used for the BA adsorption and *** maximum adsorption capacity reaches 171.1 mg g^(-1)with relative standard deviation(RSD)value of 0.2.,which is more than twice the results in the *** BA desorption rate is 97.0%at 100℃with RSD value of 0.4%,and the resins are beneficial to the reuse in the adsorption-desorption *** adsorption thermodynamics and kinetics are investigated,and the BA adsorption is a spontaneous and endothermic process with the increase of disorder *** process is mainly contributed by physical absorption and agree well with Freundlich model and pseudo-first-order adsorption kinetic *** adsorption method avoids boiling a large amount of wastewater and hopefully provides a novel alternative technology for the BA recovery.

关键词： Butyl acetate recovery Resin adsorption Desorption Thermodynamics Kinetics

Bi-level Multi-leader Multi-follower Stackelberg Game Model for Multi-energy Retail Package Optimization

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Journal of Modern Power Systems and Clean energy 2024年第1期12卷 225-237页

作者： Hongjun Gao Hongjin Pan Rui An hao Xiao Yanhong Yang Shuaijia He Junyong liu the College of Electrical Engineering Sichuan UniversityChengdu 610065China the Electric Power Research institute State Grid Jiangsu Electric Power CompanyNanjing 211100China the institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China

In the competitive energy market,energy retailers are facing the uncertainties of both energy price and demand,which requires them to formulate reasonable energy purchasing and selling strategies for improving their competitiveness in this ***,the attractive multi-energy retail packages are the key for retailers to increase their ***,combined with incentive means and price signals,five types of multi-energy retail packages such as peak-valley time-of-use(TOU)price package and day-night bundled price package are designed in this paper for *** iterative interactions between retailers and end-users are modeled using a bi-level model of stochastic optimization based on multi-leader multi-follower(MLMF)Stackelberg game,in which retailers are leaders and end-users are *** make decisions to maximize the profit considering the conditional value at risk(CVaR)while end-users optimize the satisfaction of both energy comfort and ***,a distributed algorithm is proposed to obtain the Nash equilibrium of above MLMF Stackelberg game model while the particle swarm optimization(PSO)algorithm and CPLEX solver are applied to solve the optimization model for each participant(retailer or end-user).Numeral results show that the designed retail packages can increase the overall profit of retailers,and the overall satisfaction of industrial users is the {12.est while that of residential users is the lowest after game interaction.

关键词： Conditional value at risk(CVaR) energy retailer multi-energy retail package design multi-leader multi-follower(MLMF)Stackelberg game satisfaction

In-beam gamma rays of CSNS Back-n characterized by black resonance filter

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-12页

作者： Wang, Jin-Cheng Ren, Jie Jiang, Wei Ruan, Xi-Chao liu, Ying-Yi Yang, hao-Lan Xu, Kuo-Zhi Pan, Xin-Yi Sun, Qi Bao, Jie Huang, Han-Xiong Bai, hao-Fan Bai, Jiang-Bo Cao, Ping Chen, Qi-Ping Chen, Yong-hao Duan, Wen-hao Fan, An-Chuan Fan, Rui-Rui Feng, Chang-Qing Gu, Min-hao Han, Chang-Cai Han, Zi-Jie He, Guo-Zhu He, Yong-Cheng Hong, Yang Hu, Yi-Wei Jiang, Zhi-Jie Kang, ling Lan, Chang-lin li, Bo li, Feng li, Qiang li, Xiao li, Yang liu, Jie liu, Rong liu, Shu-Bin liu, Yi-Na Luan, Guang-Yuan Ning, Chang-Jun Qiu, Yi-Jia Ren, Wen-Kai Ren, Zhi-Zhou Song, Zhao-Hui Sun, Kang Tan, Zhi-Xin Tang, Jing-Yu Tang, Sheng-Da Wang, li-Jiao Wang, Peng-Cheng Wang, Zhao-Hui Wen, Zhong-Wei Wu, Xiao-Guang Wu, Xuan Wu, Ze-Peng Xia, Cong Xie, li-Kun Yi, Han Yu, Tao Yu, Yong-Ji Zhang, Guo-Hui Zhang, Hang-Chang Zhang, Qi-Wei Zhang, Xian-Peng Zhang, Yu-liang Zhang, Zhi-Yong Zhao, Mao-Yuan Zhou, Zhi-hao Zhu, Ke-Jun Zou, Chong china Inst Atom energy Key Lab Nucl Data Beijing 102413 Peoples R China chinese Acad Sci Inst High Energy Phys Beijing 100049 Peoples R China Spallat Neutron Source Sci Ctr Dongguan 523803 Peoples R China chinese Acad Sci Inst High Energy Phys State Key Lab Particle Detect & Elect Beijing 100049 Peoples R China Univ chinese Acad Sci Beijing 100049 Peoples R China Peking Univ Sch Phys State Key Lab Nucl Phys & Technol Beijing 100871 Peoples R China Fudan Univ Inst Modern Phys Shanghai 200433 Peoples R China Univ Sci & Technol china State Key Lab Particle Detect & Elect Hefei 230026 Peoples R China Univ Sci & Technol china Sch Nucl Sci & Technol Hefei 230026 Peoples R China Univ Sci & Technol china Dept Modern Phys Hefei 230026 Peoples R China china Acad Engn Phys Inst Nucl Phys & Chem Mianyang 621900 Peoples R China Univ Sci & Technol china USTC Archaeometry Lab Hefei 230026 Peoples R China Northwest Inst Nucl Technol Xian 710024 Peoples R China Lanzhou Univ Sch Nucl Sci & Technol Lanzhou 730000 Peoples R China Univ Sci & Technol china Inst Adv Technol Hefei 230027 Peoples R China

The back-streaming white-neutron beamline (Back-n) of the china Spallation Neutron Source is an essential neutron- research platform built for the study of nuclear data, neutron {2., and neutron applications. Many types of cross-sectional neutron-reaction measurements have been performed at Back-n since early 2.18. These measurements have shown that a significant number of gamma rays can be transmitted to the experimental stations of Back-n along with the neutron beam. These gamma rays, commonly referred to as in-beam gamma rays, can induce a non-negligible experimental background in neutron-reaction measurements. Studying the characteristics of in-beam gamma rays is important for understanding the experimental background. However, measuring in-beam gamma rays is challenging because most gamma-ray detectors are sensitive to neutrons; thus, discriminating between neutron-induced signals and those from in-beam gamma rays is difficult. In this study, we propose the use of the black resonance filter method and a CeBr3 scintillation detector to measure the characteristics of the in-beam gamma rays of Back-n. Four types of black resonance filters, Ta-181, Co-59, Ag-nat, and Cd-nat, were used in this measurement. The time-of-flight (TOF) technique was used to select the detector signals remaining in the absorption region of the TOF spectra, which were mainly induced by in-beam gamma rays. The energy distribution and flux of the in-beam gamma rays of Back-n were determined by analyzing the deposited energy spectra of the CeBr3 scintillation detector and using Monte Carlo simulations. Based on the results of this study, the background contributions from in-beam gamma rays in neutron-reaction measurements at Back-n can be reasonably evaluated, which is beneficial for enhancing both the experimental methodology and data analysis.

关键词： In-beam gamma rays Back-n Black filter resonance technique In-beam gamma rays Back-n CeBr3 scintillator Black filter resonance technique C6D6 DETECTOR SYSTEM liNE

Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator

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Nuclear Science and Techniques 2024年第4期35卷 136-143页

作者： Yang Zhang Sheng-Quan Yan Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning {2. Xiao-Fei Wang Jian-Cheng liu Zhao-Hua Peng Zhuo {2.ang Ai-{2.ng {2. Jian Zheng Qi-Wen Fan Yun-Ju {2. You-Bao Wang Zhi-Hong {2. Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-hao {2. Jun-Wen Tian Jiang-{2.n Hou Chang-Xin Guo Zhi-Cheng Zhang Ming-hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao Tian Jin-Long Ma Yi-Hui liu Jing-Yu Dong Run-Long liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping liu Bing Guo china institute of Atomic {2. P.O.Box 275(10)Beijing 102413China College of Science Southern University of Science and TechnologyShenzhen 518055China School of physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as *** samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)*** this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the {2. institute of Atomic energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy *** particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the ***,an^(60)Fe sample with an abundance of 1.12.×10^(-10)was used to test the new AMS *** results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)*** sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples