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Neutrino Mass Constraints from Reconstructing the Large-scale Structure:Systematic Uncertainty

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Research in Astronomy and Astrophysics 2023年第6期23卷 65-73页

作者： Chok Lap Chung Derek Inman Xin Wang Erhao Shang zi Zhuang Fucheng Yuan Ue-li pen School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 5109082China Kavli IPMU(WPI) UTIASThe University of TokyoKashiwaChiba 277-8583Japan CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area SYSUChina Institute of Astronomy and Astrophysics Academia Sinica645 N Aohoku PlHiloHI 96720USA Canadian Institute for Theoretical Astrophysics 60 St.George StreetTorontoON M5S 3H8Canada Canadian Institute for Advanced Research 180 Dundas St WestTorontoON M5G 1Z8Canada Dunlap Institute for Astronomy and Astrophysics University of Toronto50 St George StreetTorontoON M5S 3H4Canada Perimeter Institute of Theoretical Physics 31 Caroline Street NorthWaterlooON N2L 2Y5Canada

We examine the possibility of applying the baryonic acoustic oscillation reconstruction method to improve the neutrino massΣm_ν*** to the Gaussianization of the process,we demonstrate that the reconstruction algorithm could improve the measurement accuracy by roughly a factor of *** the other hand,the reconstruction process itself becomes a source of systematic *** the algorithm is supposed to produce the displacement field from a density distribution,various approximations cause the reconstructed output to deviate on intermediate ***,it is still possible to benefit from this Gaussianized field,given that we can carefully calibrate the“transfer function”between the reconstruction output and theoretical displacement divergence from *** limitation of this approach is then set by the numerical stability of this transfer *** an ensemble of simulations,we show that such systematic error could become comparable to statistical uncertainties for a DESI-like survey and be safely neglected for other less ambitious surveys.

关键词： (cosmology:)large-scale structure of universe cosmology:observations neutrinos

Blind search for 21-cm absorption systems using a new generation of Chinese radio telescopes

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Research in Astronomy and Astrophysics 2017年第6期17卷 1-4页

作者： Hao-Ran Yu Ue-li pen Tong-Jie Zhang Di li Xuelei Chen Kavli Institute for Astronomy & Astrophysics Peking University Beijing 100871 China Canadian Institute for Theoretical Astrophysics University of Toronto Toronto M5S 3H8 ON Canada Dunlap Institute for Astronomy and Astrophysics University of Toronto Toronto M5S 3H4 ON Canada Canadian Institute for Advanced Research Program in Cosmology and Gravitation Toronto ON M5G 1Z8 Canada Perimeter Institute for Theoretical Physics Waterloo ON N2L 2Y5 Canada Department of Astronomy Beijing Normal University Beijing 100875 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Key Laboratory of Radio Astronomy Chinese Academy of Sciences Nanjing 210008 China Key Laboratory for Computational Astrophysics National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Neutral hydrogen clouds are known to exist in the Universe, however their spatial distributions and physical properties are poorly understood. Such missing information can be studied by the new generation of Chinese radio telescopes through a blind search of 21-cm absorption systems. We forecast the capabilities of surveys of 21-cm absorption systems by two representative radio telescopes in China - the Five-hundred-meter Aperture Spherical radio Telescope （FAST） and Tianlai 21-cm cosmology experiment （Tianlai）. Facilitated by either the high sensitivity （FAST） or wide field of view （Tianlai） of these telescopes, more than a thousand 21-cm absorption systems can be discovered in a few years, representing orders of magnitude improvement over the cumulative discoveries in the past half a century.

关键词： telescopes - surveys - cosmology observations

Effects of Land Use on Heavy Metal Accumulation in Soils and Sources Analysis

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Agricultural Sciences in China 2010年第11期9卷 1650-1658页

作者： BAI ling-yu ZENG Xi-bai li lian-fang pen Chang li Shu-hui Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Environment and Climate Change Ministry of Agriculture Beijing 100081 P.R.China Center of Research for Environment ＆ Resource Jilin Academy of Agricultural Sciences Changchun 136100 P.R.China

Heavy metal accumulation and its influential factors were studied in the different land use soils, which would provide a theoretical basis for controlling the content of heavy metals in soils. To identify the effects of land use on the accumulation of heavy metals in soils, 148 soil samples were collected from four land use patterns including greenhouse field, uncovered vegetable field, maize field, and forest field in Siping area of Jilin Province, China, and Cr, Ni, Cu, As, Cd, Pb, and Zn contents of those samples were determined with ICP and ICP-Mass. The result showed that there was a rather large difference in effects of the accumulation of Cr, Ni, Cu, As, Cd, and Zn in soils under different land use patterns, except Pb. Based on the assessment which compared with background concentrations in soil, the higher accumulation of heavy metals was found in greenhouse and uncovered vegetable field, much less in maize field and forest field. The mean contents of heavy metals in soils from high to low were arranged in order of greenhouse field, uncovered vegetable field, maize field, and forest field. Cd and Cu had relatively serious accumulation in soils compared to Cr, Ni, As, and Zn. The mean content of Cd in greenhouse field was 0.467 mg kg-x,which exceeded the grade II of the Chinese Soil Quality Criterion GB15618-1995 （6.5 〈pH〈7.5） for Cd standard of 0.3 mg kg^-1, while it was 5.2 times of Cd standard in the forest fields. The mean contents ofCr, Ni, Cu, As, Pb, and Zn in soils under four land use patterns were lower than the grade II of the Chinese Soil Quality Criterion. Compared with the soil cultivated years, the agricultural chemical compounds and manures application, especially the quality and quantity of applied fertilizer was one of the main reasons for leading to different accumulation of heavy metals in soils under the studied land use patterns. The accumulation of heavy metals, such as Cr, Ni, Cu, As, Cd, and Zn in soils was significantly affected by la

关键词： soil land use pattern heavy metal accumulation

Micromagnetism simulation on effects of soft phase size on Nd2Fe14B/α-Fe nanocomposite magnet with soft phase imbedded in hard phase

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Chinese Physics B 2018年第8期27卷 529-534页

作者： Yu-Qing li Ming Yue Yi pen Hong-Guo Zhang College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

In this study, micromagnetism simulation by using timte dltterence method is cameo out on the Ncl21-el415/a-Fe nanocomposite magnet with soft phase imbedded in hard phase. The effects of soft magnetic phase size （S） on the magnetic properties and magnetic reversal modes are systematically analyzed. As S increases from 1 nm to 48 nm, the remanence （Jr） increases, while the coercivity （Hci） decreases, leading to the result that the magnetic energy prod- uct [（BH）max] first increases slowly, and then decreases rapidly, peaking at S = 24 nm with the （BH）max of 72.9 MGOe （1 MGOe = 7.95775 kJ.m-3）. Besides, with the increase of S, the coercivity mechanism of the nanocomposite magnet changes from nucleation to pinning. Furthermore, by observing the magnetic moment evolution in demagnetization pro- cess, the magnetic reversal of the soft phase in the nanocomposite magnet can be divided into three modes with the increase of S： coherent rotation （S 〈 3 nm）, quasi-coherent rotation （3 nm≤S 〈 36 nm）, and the vortex-like rotation （S ≥36 nm）.

关键词： micromagnetism simulation magnetization dynamics, Nd2Fe14B/a-Fe nanocomposite magnets

Microstructure Evolution and Grain Coarsening Behaviour During Partial Remelting of Cyclic Extrusion Compression Formed AZ61 Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2013年第2期26卷 149-156页

作者： Changpeng WANG Huasheng MEI Rongqiang li Difan li ling WANG Jie liU Zehui HUA lijin ZHAO Feifei pen Hui li No.59 Institute of China Ordnance Industry

The effects of CEC passes, isothermal holding time and reheating temperature on the microstructure evolution and grain coarsening behaviour of AZ61 magnesium alloy produced by the recrystallisation and partialmelting （RAP） process were investigated. Before partial remelting, as-cast AZ61 alloy was deformed by cyclic extrusion compression （CEC） with one pass and two pass at 330 ℃. After CEC, the microstructure consisted of unrecrystallized grains and deformed eutectic compounds. Increasing isothermal holding time resulted in the formation of spheroidal grains surrounded by liquid films. With increasing the isothermal holding time, the solid grain size increased and the degree of spheroidization was improved. With increasing the reheating temperature, namely increasing liquid fraction, the solid grain size obviously decreased during the period from 560 ℃ to 570 ℃ and then slightly increased after 570 ℃, while the shape factor increased monotonously. During partial remelting, increasing reheating temperature can properly short the isothermal holding time to obtain fine structure. Moreover, increasing the numbers of CEC passes could produce finer semi-solid microstructure. The coarsening behavior of solid grains in the semi-solid state obeys Ostwald ripening and grain coalescence mechanisms. The coarsening rate constant, K, 595 ℃. After CEC plus partial remelting, the ideal and fine was suitable for thixoforming. was 80μm^3.s^-1 for samples partially remelted at semi-solid state structure can be obtained, which

关键词： AZ61 magnesium alloy Cyclic extrusion compression Microstructureevolution Grain coarsening

Hybrid Hydrogels Toughened by Chemical Covalent Bonding and Physical Electrostatic Interactions

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Chemical Research in Chinese Universities 2018年第3期34卷 500-505页

作者： liU li PAN Ge WANG licheng pen Xiuyan ZHANG Xinyue WU Guangfeng School of Chemical Engineering Changchun University of Technology Changehun 130012 P. R. China College of Chemistry Jilin University Changchun 130012 P. R. China

Polystyrene nanoparticles with negative charges（n-PSs） were synthesized using styrene（St） and sodium styrene sulfonate（NaSS） as initial materials by surfactant-free emulsion polymerization. Subsequently, a hybrid hydrogel was prepared using acrylamide（AAm） and methacryloyloxyethyltrimethyl ammonium chloride（DMC） as co-monomers with N,N＇-methylenebisacrylmnide（MBA） as a chemical crosslinker and n-PSs as a physical electrostatic interaction agent. The resulting hybrid hydrogels exhibited excellent tensile strength and elongation at break. The tensile stress of hybrid hydrogels was seven times greater than that ofhydrogels without n-PSs. The elongation at break of hydrogels reached 700%, which was much higher compared to those of the hydrogels without n-PSs. Furthermore, swelling measurements of the hydrogels indicate that there is an overshoot in the swelling process and the extent of overshoot decreases with the increasing n-PSs. Therefore, the work presented here provides a method for improving the mechanical properties of hydrogels via the introduction of polymeric nanoparticles.

关键词： Hydrogel Electrostatic interaction Mechanical property Swelling property

ZnO-chitosan/Rectorite Nanocomposite Exhibiting High Photocatalytic Activities under Visible-light Irradiation

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 310-319页

作者： li Shiqian pen-Chi Chiang DING ling Kinjal JShah CHEN Qinghua CHEN Sheng College of Ocean and Bio-chemical Engineering Fujian provincial Key Lab of Coastal Basin EnvironmentFuqing Branch of Fujian Normal UniversityFuqing 350300China Graduate Institute of Environmental Engineering National Taiwan UniversityTaipei City 10673TaiwanChina College of Chemistry and Chemical Engineering Wuhan University of Science and TechnologyWuhan 430081China College of Urban Construction Nanjing Tech UniversityNanjing 211800China Engineering Research Center of Polymer Green Recycling Ministry of Education(Fujian Normal University)Fuzhou 350007China

Chitosan(CS),hydrated zinc acetate,and rectorite(REC) were used as raw materials to prepare CS-embedded zinc oxide(ZnO) nanoparticle by a chemical precipitation ***-bonded REC-loaded ZnO-CS nanoparticle was to form ZnO-CS/REC nanocomposite photocatalyst,its morphology and structure were analyzed by means of FTIR,XRD,TGA,SEM,and *** effects of the catalyst dosage,methyl orange(MO) initial concentration and solution pH on photocatalytic performance were also *** experimental results show that the ZnO-CS/REC nanocomposite has a particle size of 100 nm with good dispersion and *** irradiation of visible light,0.6 g/L photocatalyst was used to degrade MO in solution for 90 min at pH 6,then the MO solution(10 mg/L) was decolored by more than 99%,indicating that the ZnO-CS/REC nanocomposite exhibited highly photocatalytic degradation ***,the photodegradation kinetic mechanism of MO in aqueous solution is presumed.

关键词： ZnO-Chitosan/rectorite nanocomposite visible-light methyl orange photodegradation

ASLOP:A field-access affinity-based structure data layout optimizer

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Science China(Information Sciences) 2011年第9期54卷 1769-1783页

作者： YEW pen-Chung Department of Computer Science and Engineering University of Minnesota at Twin-Cities

By rearranging the data,data layout optimizations improve the utilization of a cache line between two of its successive refills,thus reducing the total number of cache line refills and improving the performance of a *** this paper,we show that to enable structure data layout optimizations to be effective,two parameters,namely intra-instance affinity and inter-instance affinity,need to be considered at the same time in order to model the cache line utilization more *** also propose a lightweight approach to measure intra-instance affinity and inter-instance affinity to avoid complex memory trace analyses.A prototype,called ASLOP,has been implemented in the Open64 compiler and evaluated using benchmarks from SPEC CPU 2000,SPEC CPU 2006 and Olden benchmark suites that have extensive structure *** approach can achieve up to 48.1% performance improvement over the original programs,and 11.9% over the optimized programs using maximal reshaping,an existing approach that is known to produce close to the best results,on the two platforms we tested.

关键词： compiler optimization data-layout optimization memory hierarchy inter-instance affinity intra-instance affinity

要么忠实,要么美丽——以策兰、里尔克、狄金森为例谈诗歌翻译技巧

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南都学坛 2025年第1期45卷 32-43页

作者：岩子欧洲华文笔会奥地利维也纳1230

诗歌是一种具有偶然性的、关乎灵感的精神产物,呈现出非数据性、非实事性和非技术性的特点,常常令人难以进行翻译。诗歌翻译中难以传递和把握的意象、意境和用典,不仅记载着写作个体发生于刹那间的、灵感突现式的“理解与情感的复杂经验... 详细信息

诗歌是一种具有偶然性的、关乎灵感的精神产物,呈现出非数据性、非实事性和非技术性的特点,常常令人难以进行翻译。诗歌翻译中难以传递和把握的意象、意境和用典,不仅记载着写作个体发生于刹那间的、灵感突现式的“理解与情感的复杂经验”,亦蕴含着来自出发语的千百年来沉淀而成的文化和艺术的审美经验。翻译工作者在“摆渡”不同语言写成的文学作品时,难免会遇到直译或意译、押韵与否、是否可译、死译或活译等问题。诗歌翻译要最大程度地保持原作的结构、风貌乃至气韵,力求精神上的忠实,以灵活的方式穿越语言和文化的屏障,以译入语的语言系统为准绳,使原诗脱胎换骨,美丽再生,打动目的语受众的心弦。

关键词：诗歌翻译摆渡策兰里尔克狄金森

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