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Mantle geochemistry: Insights from ocean island basalts

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Science China Earth Sciences 2017年第11期60卷 1976-2000页

作者： huang ShiChun zheng YongFei Department of Geoscience University of Nevada CAS Key Laboratory of Crust-Mantle Material and Environment School of Earth and Space Sciences University of Science and Technology of China

The geochemical study of the Earth's mantle provides important constraints on our understanding of the formation and evolution of Earth, its internal structure, and the mantle dynamics. The bulk Earth composition is inferred by comparing terrestrial mantle rocks with chondrites, which leads to the chondritic Earth model. That is, Earth has the same relative proportions of refractory elements as that in chondrites, but it is depleted in volatiles. Ocean island basalts(OIB) may be produced by mantle plumes with possible deep origins; consequently, they provide unique opportunity to study the deep Earth. Isotopic variations within OIB can be described using a limited number of mantle endmembers, such as EM1, EM2 and HIMU, and they have been used to decipher important mantle processes. Introduction of crustal material into the deep mantle via subduction and delamination is important in generating mantle heterogeneity; however, there is active debate on how they were sampled by mantle melting, i.e.,the role of olivine-poor lithologies in the OIB petrogenesis. The origin and location of high 3He/4He mantle remain controversial,ranging from unprocessed(or less processed) primitive material in the lower mantle to highly processed materials with shallow origins, including ancient melting residues, mafic cumulates under arcs, and recycled hydrous minerals. Possible core-mantle interaction was hypothesized to introduce distinctive geochemical signatures such as radiogenic 186 Os and Fe and Ni enrichment in the OIB. Small but important variations in some short-lived nuclides, including 142 Nd, 182 W and several Xe isotopes, have been reported in ancient and modern terrestrial rocks, implying that the Earth's mantle must have been differentiated within the first 100 Myr of its formation, and the mantle is not efficiently homogenized by mantle convection.

关键词： Mantle structure Mantle composition Crustal components Crust-mantle interaction Crustal recycling

EFFECTS OF SMALL ADDITIONS OF Mg AND Ag ON PRECIPITATION PROCESS OF Al-Cu-Li-(Mg)-(Ag)-Zr ALLOYS

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中国有色金属学会会刊：英文版 1998年第3期8卷 2-7页

作者： Ziqiao, zheng Biping, huang Central South Univ of Technology Changsha China

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｔｅｒｎａｒｙＡｌＣｕＭｇａｌｏｙｓｗｉｔｈｈｉｇｈＣｕ∶Ｍｇｍａｓｓｒａｔｉｏｓ，ｓｍａｌａｄｄｉｔｉｏｎｓｏｆＭｇｐｒｏｍｏｔｅｔｈｅｐｒｅｃｉｐｉｔａｔｉｏｎｏｆｓｔｒｅｎｇｔ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｔｅｒｎａｒｙＡｌＣｕＭｇａｌｏｙｓｗｉｔｈｈｉｇｈＣｕ∶Ｍｇｍａｓｓｒａｔｉｏｓ，ｓｍａｌａｄｄｉｔｉｏｎｓｏｆＭｇｐｒｏｍｏｔｅｔｈｅｐｒｅｃｉｐｉｔａｔｉｏｎｏｆｓｔｒｅｎｇｔｈｅｎｉｎｇｐｈａｓｅｓｗｈｉｃｈ...

关键词： Al Li alloys microstructure precipitation silver magnesium

Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith

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Science China Earth Sciences 2025年第1期68卷 195-207页

作者： Peng ZHANG Xin LIU Guanghui LIU Wei DAI Hanzhe YANG Haibo zheng Zhi WANG Ran NIU Yifan BAI Yang ZHANG Chengbao LIU Ge YANG Junwei YANG Guang ZHANG Technology and Engineering Center for Space Utilization Chinese Academy of Sciences Beijing Hegong Simulation Co. Ltd

The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions. The classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar resources. In this study, we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation method. The scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic properties. Detailed modeling of the dry magnetic separation device is conducted, and the three-dimensional distribution of magnetic parameters is calculated and analyzed. Based on the characterization and analysis of the chang E-5's samples, the morphologies and physical parameters of lunar regolith particles are modeled and simulated. A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed, and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are investigated. Our results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum speed. Additionally, we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process, showing that these factors can obviously enhance the beneficiation process of lunar ilmenites. This study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith, providing a theoretical basis for the scientific tasks of collecting, processing, and utilizing lunar mineral resources.

关键词： Lunar regolith In-situ resource utilization Magnetic separation Classified sampling

An Analogue of Beurling's Theorem for NA Groups

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Acta Mathematica Sinica,English Series 2013年第5期29卷 841-856页

作者： Ji zheng huang College of Sciences North China University of Technology

In this paper, we prove Beurling＇s theorem for NA groups, from which we derive some other versions of uncertainty principles.

关键词： NA groups uncertainty principle Beurling's theorem radon transform

Heavy soil drying during mid-to-late grain filling stage of the main crop to reduce yield loss of the ratoon crop in a mechanized rice ratooning system

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The Crop Journal 2022年第1期10卷 280-285页

作者： chang zheng Yuechao Wang Shen Yuan Sen Xiao Yating Sun Jianliang huang Shaobing Peng National Key Laboratory of Crop Genetic Improvement Hubei Hongshan LaboratoryMARA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze RiverCollege of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070HubeiChina

Yield loss(Y_(Loss)) in the ratoon crop due to crushing damage to left stubble from mechanical harvesting of the main crop is a constraint for wide adoption of mechanized rice ratooning *** drying before the harvest of the main crop has been proposed to overcome this *** objective of this study was to determine the effect of soil drying during the mid-to-late grain filling stage of the main crop on grain yield of the ratoon crop in a mechanized rice ratooning *** experiments were conducted to compare Y_(Loss) between light(LD) and heavy(HD) soil drying treatments in Hubei province,central China in 2017 and 2018.Y_(Loss) was calculated as the percentage of yield reduction in the ratoon crop with the main crop harvested mechanically,relative to the grain yield of the ratoon crop with the main crop harvested *** comparison with LD,soil hardness was increased by 42.8%-84.7% in HD at the 5-20 cm soil depth at maturity of the main *** hardness at 5 and 10 cm depths reached respectively 4.05 and 7.07 kg cm^(-2) in *** drying treatment did not significantly affect the grain yield of the main *** mechanical harvesting of the main crop,HD increased the grain yield of the ratoon crop by 9.4% relative to ***,Y_(Loss) was only 3.4% in HD,in contrast to 16.3% in *** differences in grain yield and Y_(Loos) between the two soil drying treatments were explained mainly by panicles m^(-2),which was increased significantly by HD in the track zone of the ratoon crop compared with *** results suggest that heavy soil drying practice during the mid-to-late grain filling stage of the main crop is effective for reducing Y_(Loss) of the ratoon crop in a mechanized rice ratooning system.

关键词： Crushing damage Mechanical harvesting Ratoon rice Soil drying Yield loss

A proposal on complementary determination of the effective electro-weak mixing angles via doubly heavy-flavored hadron production at a super Z-factory

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Science China(Physics,Mechanics & Astronomy) 2020年第8期63卷 61-70页

作者： Xu-chang zheng Chao-Hsi chang Tai-Fu Feng Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics Chongqing UniversityChongqing 401331China China Center of Advanced Science and Technology(CCAST)(World Laboratory) Beijing 100190China Department of Physics Hebei UniversityBaoding 071002China

To test the standard model(SM)precisely and to look for the clues deviating from SM,a proposal for determining the effective electro-weak mixing angles sin2θefff(particularly f=lept,c,b)is *** is via observing the asymmetries(the forward-backward one AFB,the left-right one ALR and the combined left-right forward-backward one ALRFB)of the doubly heavy-flavored hadrons in the production at a super Z-factory(an e+e-collider designed with a luminosity as high as possible for modernday techniques runs around the center-of-mass energy s1/2=mZ).To see the sensitivity,uncertainties as well as the event accumulation precisely,the observables for describing the asymmetries of the produced hadrons are computed numerically with varying effective mixing angles,and based on the result analyses,it is concluded that the proposal may offer an independent complement determination of the effective mixing angles.

关键词： electro-weak mixing angle production of doubly heavy-flavored hadron asymmetries super Z-factory

Synthesis and characterization of a tetradentate PNCP iridium complex for catalytic alkane dehydrogenation

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Science China Chemistry 2015年第8期58卷 1340-1344页

作者： Xiangqing Jia zheng huang State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

A novel hydrido iridium chloride complex supported by a tetradentate PNCP ligand has been synthesized and characterized. Upon activation with NaOtBu, the PNCP-IrHC1 complex is active for transfer dehydrogenation of cy... 详细信息

关键词： alkane dehydrogenation iridium tetradentate ligand

Effects of the momentum dependence of nuclear symmetry potential on pion observables in Sn+Sn collisions at 270 MeV/nucleon

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Nuclear Science and Techniques 2022年第12期33卷 147-158页

作者： Gao‑Feng Wei Xin huang Qi‑Jun Zhi Ai‑Jun Dong chang‑Gen Peng zheng‑Wen Long School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550025China Guizhou Provincial Key Laboratory of Public Big Data Guizhou UniversityGuiyang 550025China College of Physics Guizhou UniversityGuiyang 550025China

Within a transport model,we investigated the effects of the momentum dependence of the nuclear symmetry potential on the pion observables in central Sn+Sn collisions at 270 MeV/*** this end,the quantity U^(∞)_(sym)(ρ_(0))(i.e.,the value of the nuclear symmetry potential at the saturation densityρ_(0) and infinitely large nucleon momentum)was used to characterize the momentum dependence of the nuclear symmetry *** a certain L(i.e.,the slope of the nuclear symmetry energy at(ρ_(0))),the characteristic parameter U^(∞)_(sym)(ρ_(0))of the symmetry potential significantly affects the production of−and+and their pion ***,by comparing the charged pion yields,pion ratios,and spectral pion ratios of the theoretical simulations for the reactions ^(108) Sn+^(112) Sn and ^(132)Sn+^(124)Sn with the corresponding data in the SRIT experiments,we found that our results favor a constraint on U^(∞)_(sym)(ρ_(0))(i.e.,−160_(−9)^(+18) MeV),and L is also suggested within a range of 62.7 MeV

关键词： Nuclear symmetry potential Momentum dependence Symmetry energy

Assessment of composite failure and ultimate strength without experiment on composite

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Acta Mechanica Sinica 2014年第4期30卷 569-588页

作者： zheng-Ming huang Ling Liu School of Aerospace Engineering & Applied Mechanics Tongji University Micromechanics of Materials Zernike Institute for Advanced MaterialsUniversity of Groningen

This paper attempts to estimate the ultimate strength of a laminated composite only based on its con- stituent properties measured independently. Three important issues involved have been systematically addressed, i.e., stress calculation for the constituent fiber and matrix materials, failure detection for the lamina and laminate upon the internal stresses in their constituents, and input data determination of the constituents from monolithic measurements. There are three important factors to influence the accuracy of the strength prediction. One is the stress concentration factor （SCF） in the matrix. Another is matrix plasticity. The third is thermal residual stresses in the constituents. It is these three factors, however, that have not been sufficiently well realized in the composite community. One can easily find out the elastic and strength parameters of a great many laminae and laminates in the current literature. Unfortunately, necessary information to determine the SCF, the matrix plasticity, and the thermal residual stresses of the composites is rare or incomplete. A useful design methodology is demonstrated in the paper.

关键词： Composite · Strength · Stress concentrations ·Plasticity · Residual stress · Bridging model