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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 & li {3.1,2,3.1 key laboratory of particle astrophysics, institute of high energy physics, chinese academy of sciences, beijing 100049, china 2 Department of physics & Center for astrophysics, Tsinghua University, beijing 100084, china 3.Department of Engineering physics & Center for astrophysics, Tsinghua University, beijing 100084, china key laboratory of particle {3. 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 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 & li {3.1,2,3.1 key laboratory of particle astrophysics,institute of high energy physics,chinese academy of sciences,beijing 100049,china 2 Department of physics & Center for astrophysics,Tsinghua University,beijing 100084,china 3.Department of Engineering physics & Center for astrophysics,Tsinghua University,beijing 100084,china key laboratory of particle {3. 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 3. spherical geodynamic modeling

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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 liu 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 lithospheric 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 particle-in-cell method as a strategy for improving the solution to the {3. 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-li li Department of Engineering physics Tsinghua UniversityBeijing 100084China key laboratory of particle 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 utilizes simplified 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 normalized 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%,25%,50%,75%,and 100%)and compressed breast thicknesses(2,3.4,5,6,and 7 cm)at various tube potentials(25,28,3.,3.,3.,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-energy 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 Na2SO4 solution,showing excellent corrosion *** with MKPC river sand(RS)mortar,the hydration products of CS mortar were an intermediate product 6KPO2·8H2O 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 {3. 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 23..1 nm and average particle size of about 526.5μm 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

Research on the knee region of cosmic ray by using a novel type of electron-neutron detector array

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Frontiers of physics 2024年第4期19卷 13-24页

作者： Bing-Bing li Xin-Hua Ma Shu-Wang Cui hao-Kun Chen Tian-Lu Chen Danzengluobu Wei Gao Hai-Bing Hu Denis Kuleshov Kirill Kurinov Hu liu Mao-Yuan liu Ye liu Da-Yu Peng Yao-Hui Qi Oleg Shchegolev Yuri Stenkin li-Qiao Yin Heng-Yu Zhang liang-Wei Zhang College of physics Hebei Normal UniversityShijiazhuang 050024China key laboratory of particle {3. Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China TIANFU Cosmic Ray Research Center Chengdu 610000China College of Science Tibet UniversityLhasa 850000China key laboratory of Comic Rays Ministry of EducationTibet UniversityLhasa 850000China institute for Nuclear Research of the Russian academy of sciences Moscow 117312Russia School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China School of Management Science and Engineering Hebei University of Economics and BusinessShijiazhuang 050061China Moscow institute of physics and Technology Moscow 141700Russia

By accurately measuring composition and energy spectrum of cosmic ray,the origin problem of so called“knee”region(energy>one PeV)can be ***,up to the present,the results of the spectrum in the knee region obtained by several previous experiments have shown obvious differences,so they cannot give effective evidence for judging the theoretical models on the origin of the ***,the Large high Altitude Air Shower Observatory(LHAASO)has reported several major breakthroughs and important results in astro-{3. physics *** on its advantages of wide-sky survey,high altitude location and large area detector arrays,the research content of LHAASO experiment mainly includes ultra high-energy gamma-ray astronomy,measurement of cosmic ray spectra in the knee region,searching for dark matter and new phenomena of {3. physics at higher *** electron and thermal neutron detector(EN-Detector)is a new scintillator detector which applies thermal neutron detection technology to measure cosmic ray extensive air shower(EAS).This technology is an extension of *** EN-Detector Array(ENDA)can highly efficiently measure thermal neutrons generated by secondary hadrons so called“skeleton”of *** this paper,we perform the optimization of ENDA configuration,and obtain expectations on the ENDA results,including thermal neutron distribution,trigger efficiency and capability of cosmic ray composition *** obtained real data results are consistent with those by the Monte Carlo simulation.

关键词： cosmic ray EAS knee region LHAASO ENDA

Nondestructive technique for identifying nuclides using neutron resonance transmission analysis at CSNS Back-n

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Nuclear Science and Techniques 2024年第1期35卷 178-187页

作者： Sheng-Da Tang Yong-hao Chen Jing-Yu Tang Rui-Rui Fan Qiang li Gong li Dong {3. Zheng-Yao Jin Xing-Zhu Cui Tian-Xiang Chen Yi-Wei Yang Rong {3. Han Yi Yang li Zhen Yang Qi An hao-Fan Bai Jiang-Bo Bai Jie Bao Ping Cao Qi-Ping Chen Zhen Chen Zeng-Qi Cui An-Chuan Fan Chang-Qing Feng Fan-Zhen Feng Ke-Qing Gao Min-hao Gu Chang-Cai Han Zi-Jie Han Guo-Zhu He Yong-Cheng He Yang Hong Yi-Wei Hu Han-Xiong Huang Wei-Hua Jia hao-yu Jiang Wei Jiang Zhi-jie Jiang ling Kang Bo li Chao li Jia-Wen li Xiao li Jie {3. Shu-Bin {3. Guang-Yuan Luan Chang-Jun Ning Bin-Bin Qi Jie Ren Zhi-Zhou Ren Xi-Chao Ruan Zhao-Hui Song Kang Sun Zhi-Xin Tan li-Jiao Wang Peng-Cheng Wang Zhao-Hui Wang Zhong-Wei Wen Xiao-Guang Wu Xuan Wu li-Kun Xie Yong-Ji Yu Guo-Hui Zhang lin-hao Zhang Mo-Han Zhang Qi-Wei Zhang Xian-Peng Zhang Yu-liang Zhang Yue Zhang Zhi-Yong Zhang Mao-Yuan Zhao Lu-Ping Zhou Zhi-hao Zhou Ke-Jun Zhu Sino-French institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China institute of high-energy {3. Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China State key laboratory of particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China State key laboratory of particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China USTC Archaeometry laboratory University of Science and Technology of ChinaHefei 230026China institute of Nuclear physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Department of Modern physics University of Science and Technology of ChinaHefei 230026China State key laboratory of Nuclear physics and Technology School of PhysicsPeking UniversityBeijing 100871China key laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China Northwest institute of Nuclear Technology Xi’an 710024China University of chinese academy of sciences Beijing 100049China

Nondestructive and noninvasive neutron assays are essential applications of neutron *** resonance transmission analysis(NRTA)is a powerful nondestructive method for investigating the elemental composition of an *** back-streaming neutron line(Back-n)is a newly built time-of-flight facility at the china Spallation Neutron Source(CSNS)that provides neutrons in the eV to 3.0 MeV range.A feasibility study of the NRTA method for nuclide identification was conducted at the CSNS Back-n via two test *** results demonstrate that it is feasible to identify different elements and isotopes in samples using the NRTA method at *** study reveals its potential future applications.

关键词： CSNS White neutron beam NRTA Nuclide identification Nondestructive method

Design and prototyping of the readout electronics for the transition radiation detector in the high energy cosmic radiation detection facility

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Nuclear Science and Techniques 2024年第4期35卷 189-199页

作者： Jie-Yu Zhu Yang-Zhou Su Hai-Bo Yang Fen-Hua Lu Yan Yang Xi-Wen liu Ping Wei Shu-Cai Wan hao-Qing Xie Xian-Qin li Cong Dai Hui-Jun Hu Hong-Bang liu Shu-Wen Tang Cheng-Xin Zhao institute of Modern physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Guangxi key laboratory for Relativistic astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

The high energy cosmic-radiation detection(HERD)facility is planned to launch in 2027 and scheduled to be installed on the {3. Space *** serves as a dark matter particle detector,a cosmic ray instrument,and an observatory for high-energy gamma rays.A transition radiation detector placed on one of its lateral sides serves dual purpose,(ⅰ)calibrating HERD's electromagnetic calorimeter in the TeV energy range,and(ⅱ)serving as an independent detector for high-energy gamma *** this paper,the prototype readout electronics design of the transition radiation detector is demonstrated,which aims to accurately measure the charge of the anodes using the SAMPA application specific integrated circuit *** electronic performance of the prototype system is evaluated in terms of noise,linearity,and *** the presented design,each electronic channel can achieve a dynamic range of 0–100 fC,the RMS noise level not exceeding 0.15 fC,and the integral nonlinearity was<0.2%.To further verify the readout electronic performance,a joint test with the detector was carried out,and the results show that the prototype system can satisfy the requirements of the detector's scientific goals.

关键词： HERD Dark matter particle detection TRD Readout electronics SAMPA Data acquisition Performance test