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Journal of Environmental Sciences 2009年第7期21卷 872-876页

作者： ZHANG Lizhu MA Jun LI xin WANG Shutao School of Science Harbin Institute of Technology Harbin 150090 China School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

The effect of permanganate preoxidation on organic matter removal during the coagulation with aluminum chloride was investigated using tannic acid as a model compound. Results showed that a small amount of KMnO4 （0.75 mg/L） increased the removal efficiency of tannic acid up to 20%, as compared to the process of coagulation by aluminum chloride alone. The key factor enhancing the removal efficiency of tannic acid in preoxidation process was the in situ formation of a reductant manganese dioxide. The complexation model was used to describe the reaction between MnO2 and tannic acid. Under weak pH condition, tannic acid was difficult to be adsorbed by MnO2 due to the static electrical repulsive forces. The presence of Ca2＋ served as a bridge to hold the negative charged MnO2 and tannic acid together, which could be a crucial factor influencing tannic acid adsorption by in-situ manganese dioxide.

关键词： KMnO4 MnO2 adsorption coagulation oxidation tannic acid

Congruences for finite triple harmonic sums

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 946-948页

作者： FU Xu-dan ZHOU xia CAI Tian-xin Department of Mathematics Zhejiang University Hangzhou 310028 China Hangzhou Foreign Language School Hangzhou 310023 China

Zhao （2003a） first established a congruence for any odd prime p〉3, S（1,1,1 ;p）=-2Bp-3 （mod p）, which holds when p=3 evidently. In this paper, we consider finite triple harmonic sum S（α,β, γ,ρ）（modp） is considered for all positive integers α,β, γ. We refer to w=α＋β＋ γ as the weight of the sum, and show that if w is even, S（α,β, γ,ρ）=0 （mod p） for p≥w＋3; if w is odd, S（α,β, γ,ρ）=-rBp-w （mod p） for p≥w, here r is an explicit rational number independent ofp. A congruence of Catalan number is obtained as a special case.

关键词： Finite triple harmonic sums Recursive relation Bernoulli numbers Catalan numbers

Carbody Structural Lightweighting Based on Implicit Parameterized Model

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 483-487页

作者： CHEN xin MA Fangwu WANG Dengfeng xiE Chen State Key Laboratory of Automotive Simulation and Control Jilin University Zhejiang Geely Automobile Research Institute Co. Ltd

Most of recent research on carbody lightweighting has focused on substitute material and new processing technologies rather than structures. However, new materials and processing techniques inevitably lead to higher costs. Also, material substitution and processing lightweighting have to be realized through body structural profiles and locations. In the huge conventional workload of lightweight optimization, model modifications involve heavy manual work, and it always leads to a large number of iteration calculations. As a new technique in carbody lightweighting, the implicit parameterization is used to optimize the carbody structure to improve the materials utilization rate in this paper. The implicit parameterized structural modeling enables the use of automatic modification and rapid multidisciplinary design optimization （MDO） in carbody structure, which is impossible in the traditional structure finite element method （FEM） without parameterization. The structural SFE parameterized model is built in accordance with the car structural FE model in concept development stage, and it is validated by some structural performance data. The validated SFE structural parameterized model can be used to generate rapidly and automatically FE model and evaluate different design variables group in the integrated MDO loop. The lightweighting result of body-in-white （BIW） after the optimization rounds reveals that the implicit parameterized model makes automatic MDO feasible and can significantly improve the computational efficiency of carbody structural lightweighting. This paper proposes the integrated method of implicit parameterized model and MDO, which has the obvious practical advantage and industrial significance in the carbody structural lightweighting design.

关键词： carbody structural lightweighting implicit parameterization MDO BIW

Chemical Potential Dependence of the Dressed-Quark Propagator in a Simple Confining QCD Model

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Chinese Physics Letters 2004年第7期21卷 1232-1235页

作者： ZONGHong-Shi HOUFeng-Yao CHENxiang-Song LIUYu-xin DepartmentofPhysics NanjingUniversityNanjing210093 DepartmentofPhysics SichuanUniversityChengdu610064 DepartmentofPhysics PekingUniversityBeijing100871

Based on the Dyson-Schwinger approach, a method for obtaining the chemical potential dependence of the dressed quark propagator in the "Nambu-Goldstone" and the "Wigner" phase is developed. The bag constant in the pre... 详细信息

关键词： Nuclear physics

Modeling of shell-mixing into the central hotspot in inertial confinement fusion implosion

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Modeling of shell-mixing into the central hotspot in inertia...

2016第八届全国计算物理会议

作者： YU cheng-xin FAN Zheng-feng Institute of Applied Physics and Computational Mathematics

Starting from the mass conservation and energy conservation of hotspot,the dynamics of hotspot combustion involving shell-mix are constructed by recalculating the special internal energy and heat capacity,in which the bremsstrahlung radiation loss and other energy transfer are *** the power balance in the hotspot,the relations between the fractions of shell-mixing in the hotspot and the ignition threshold and self-sustainable combustion are *** theoretical analysis and numerical simulation show that the enhancement of radiation loss induced by the shell-mixing plays the dominated role in the failure of *** adjusting different materials and the mixing fraction,the effects to the combustion paths are studied.

关键词： Inertial confinement fusion Implosion mixing Hotspot combustion Degradation of shell-mixing

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汾渭断陷带现今垂直形变与近期地震活动性

地震 2012年第4期32卷 123-130页

作者：张四新张希中国地震局第二监测中心陕西西安710054

本文针对2008年汶川地震后鄂尔多斯块体周缘出现的小震活跃现象,利用分布于汾渭断陷带不同部位的跨断裂水准资料,分析了其近期的垂直形变演化过程。结果表明:①各水准剖面的垂直差异运动幅度基本稳定在±20mm之间,且在小震活动期间未出... 详细信息

本文针对2008年汶川地震后鄂尔多斯块体周缘出现的小震活跃现象,利用分布于汾渭断陷带不同部位的跨断裂水准资料,分析了其近期的垂直形变演化过程。结果表明:①各水准剖面的垂直差异运动幅度基本稳定在±20mm之间,且在小震活动期间未出现明显的形变异常;②鄂尔多斯块体周缘近期小震活跃可能是缘于汶川地震后,青藏块体挤压应力减弱,华北块体对其推挤作用相对增强而造成鄂尔多斯块体的水平挤压应力场的"暂态失稳"所致。

关键词：跨断裂水准垂直形变地震活动性汾渭断陷带

Pore Engineering for Covalent Organic Framework Membranes

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Chemical Research in Chinese Universities 2022年第2期38卷 364-372页

作者： YAO Jin LU Ya SUN Huihui ZHAO xin Key Laboratory of Synthetic and Self-assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032P.R.China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024P.R.China College of Chemistry and Materials Science Shanghai Normal UniversityShanghai 200234P.R.China

Membrane technology is of particular significance for the sustainable development of society owing to its potential capacity to tackle the energy shortage and environmental *** materials are the core part of membrane *** have always been pursuing predictable structures of advanced membrane materials,which provides a possibility to fully unlock the potential of *** organic frameworks(COFs),with the advantage of controllable pore microenvironment,are considered to be promising candidates to achieve this design *** customizable function of COF membranes through pore engineering does well in the enhancement of selective permeability performance,which offers COF membranes with great application potentials in separation and transportation *** this context,COF-based membranes have been developed rapidly in recent ***,we present a brief overview on the strategies developed for pore engineering of COF membranes in recent years,including skeleton engineering,pore surface engineering,host-guest chemistry and membrane ***,the features of transmission or separation of molecules/ions based on COF membranes and corresponding applications are also *** the last part,the challenges and prospects of the development of COF membranes are discussed.

关键词： Membrane technology Covalent organic framework(COF) Pore engineering Separation Ion transportation

Carbon Enrichment in the Lithospheric Mantle:Evidence from the Melt Inclusions in Mantle Xenoliths from the Hainan Basalts

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Acta Geologica Sinica(English Edition) 2023年第1期97卷 358-375页

作者： XU xin TIAN Wei ZHANG Lifei LI Huijuan The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking UniversityBeijing 100871China

It is generally believed that the lithospheric mantle and the mantle transition zone are important carbon ***,the location of carbon storage in Earth's interior and the reasons for carbon enrichment remain *** this study,we report CO_(2)-rich olivine-hosted melt inclusions in the mantle xenoliths of late Cenozoic basalts from the Penglai area,Hainan Province,which may shed some light on the carbon enrichment process in the lithospheric *** also present a detailed petrological and geochemical investigation of the late Cenozoic basalts and mantle xenoliths from northern Hainan *** collected samples of late Cenozoic Hainan Island basalts belong to both alkaline and subalkaline series,showing fractionated REE patterns with high(La/Yb)_(N)values of 3.52–11.77,which are typical for *** on Al-in-olivine thermometry,the temperatures estimated for the mantle xenoliths can be divided into two *** group has temperatures of less than 1050℃,and the other group has temperature ranging from 1050℃to 1282℃.Clinopyroxene(La/Yb)_(N)–Ti/Eu and clinopyroxene Ca/Al–Mg^(#)diagrams indicate that the mantle peridotite experienced metasomatism from both silicate and carbonate *** inclusions in the olivine of mantle xenoliths include(1)CO_(2)bubble–rich melt inclusions;(2)multiphase melt inclusions(glass+CO_(2)bubble+daughter minerals);(3)pure glass melt *** is a daughter mineral in the olivine-hosted melt inclusions,which could be interpreted as a secondary mineral formed by the interactions of CO_(2)-rich fluids with an olivine host,due to post-entrapment *** glasses in olivine-hosted melt inclusions have high SiO_(2)contents(60.21–77.72 wt%).Our results suggest that a considerable amount of CO_(2)-rich melt inclusions are captured in the lithospheric mantle during *** lithospheric mantle can therefore act as is a‘carbon trap',with much CO_(2)being absorbed by the lithospheric mantle in this way.

关键词： melt inclusions lithospheric mantle metasomatism carbon trap Hainan Island

Study of CO adsorption on perfect and defective pyrite (100) surfaces by density functional theory

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Journal of Natural Gas Chemistry 2011年第1期20卷 60-64页

作者： Yudong Du Wenkai Chen Yongfan Zhang xin Guo Department of Chemistry Fuzhou University Fuzhou 350108 Fujian China： State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 410074 Hubei China

First-principles calculations based on density functional theory （DFT） and the generalized gradient approximation （GGA） have been used to study the adsorption of CO molecule on the perfect and defective FeS 2 （100） surfaces. The defective Fe 2 S（100） surfaces are caused by sulfur deficiencies. Slab geometry and periodic boundary conditions are employed with partial relaxations of atom positions in calculations. Two molecular orientations, Cand O-down, at various distinct sites have been considered. Total energy calculations indicated that no matter on perfect or deficient surfaces, the Fe position is relatively more favored than the S site with the predicted binding energies of 120.8 kJ/mol and 140.8 kJ/mol, respectively. Moreover, CO was found to be bound to Fe atom in vertical configuration. The analysis of density of states and vibrational frequencies before and after adsorption showed clear changes of the C–O bond.

关键词： density functional theory carbon monoxide FeS 2 (100) sulfur vacancy adsorption

Synthesis and characterization of cadmium-calcium hydroxyapatite solid solutions

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International Journal of Minerals,Metallurgy and Materials 2014年第6期21卷 604-608页

作者： xin Zhao Yi-nian Zhu Liu-qin Dai College of Light Industry and Food Engineering Guangxi University College of Environmental Science and Engineering Guilin University of Technology

A series of cadmium-calcium hydroxyapatite solid solutions was prepared by an aqueous precipitation method. By various means, the characterizations confirmed the formation of continuous solid solutions over all ranges of Cd/（Cd＋Ca） atomic ratio. In the results, both lattice parameters a and c display slight deviations from Vegard’s rule when the Cd/（Cd＋Ca） atomic ratio is greater than 0.6. The particles change from smaller acicular to larger hexagonal columnar crystals as the Cd/（Cd＋Ca） atomic ratio increases from 0-0.60 to 0.60-1.00. The area of the phosphate peak for symmetric P-O stretching decreases with the increase in Cd/（Cd＋Ca） atomic ratio, and the peak disappears when the Cd/（Cd＋Ca） atomic ratio is greater than 0.6; the two phosphate peaks of P-O stretching gradually merge together for the Cd/（Cd＋Ca） atomic ratio near 0.60. These variations can be explained by a slight tendency of larger Cd ions to occupy M（2） sites and smaller Ca ions to prefer M（1） sites in the structure.

关键词： hydroxyapatite solid solutions cadmium calcium substitution