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Propagation and Evolution of a Scalar Field in Einstein-Power-Maxwell Spacetime

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Chinese Physics Letters 2012年第1期29卷 31-34页

作者： LIU Yan jing Ji-liang Department of Physics and Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of EducationHunan Normal UniversityChangsha 410081

The propagation and dynamical evolution of a scalar field in the background of a(2+1)-dimensional Einstein–Power–Maxwell(EPM)black hole are *** obtain an analytical expression for the greybody factor,which shows that the greybody factor increases as the electric charge increases and approaches unity for large *** also find the quasinormal modes of the black hole,which tell us that the EPM spacetime is very stable.

关键词： Maxwell black Power

Size-controlled chalcopyrite CuInS_2 nanocrystals:One-pot synthesis and optical characterization

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Science China Chemistry 2012年第7期55卷 1236-1241页

作者： PENG ShengJie liang Yanliang CHENG FangYi liang jing Key Laboratory of Functional Polymer Materials Ministry of EducationCollege of ChemistryNankai UniversityTianjin 300071China

Chalcopyrite ternary CulnS2 semiconductor nanocry stals have been synthesized via a facile one-pot chemical approach by using oleylamine and oleic acid as solvents. The as-prepared CuInS2 nanocrystals have been characterized by instrumental analyses such as X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, transmission electron microscopy （TEM）/high-resolution TEM （HRTEM）, energy-dispersive X-ray spectroscopy （EDS）, UV-vis absorption spectroscopy （UV-vis） and photoluminescence （PL） spectroscopy. The particle sizes of the CuInS2 nanocrystals could be tuned from 2 to 10 nm by simply varying reaction conditions. Oleylamine, which acted as both a reductant and an effective capping agent, plays an important role in the size-controlled synthesis of CulnS2 nanocrystals. Based on a series of comparative experiments under different reaction conditions, the probable formation mechanism of CulnS2 nanocrystals has been proposed. Furthermore, the UV-vis absorption and PL emission spectra of the chalcopyrite CulnS2 nanocrystals have been found to be adjustable in the range of 527-815 nm and 625-800 rim, respectively, indicating their potential application in photovoltaic devices.

关键词： CuInS2 nanocrystals one-pot synthesis optical property

Inhibition Performance of Enhanced-Mo Inhibitor for Carbon Steel in 55% LiBr Solution

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Journal of Iron and Steel Research International 2008年第1期15卷 49-54页

作者： liang Cheng-hao HU Xian-qi Electromechanics and Materials Engineering College Dalian Maritime University Dalian 116026 Liaoning China School of Chemical Engineering Dalian University of Technology Dalian 116012 Liaoning China

The inhibition performance of enhanced-Mo inhibitor for carbon steel in 55% LiBr solution was measured by means of chemical immersion,electrochemical measurements,and physical detection *** indicated that enhanced-Mo inhibitor showed excellent inhibition performance of carbon steel in 55% LiBr solution,especially at high *** increasing the temperature of solution from 160 ℃ to 240 ℃,the corrosion rates of carbon steel increased from 17.67 μm/a to 33.07 μm/***-Mo inhibitor might improve the anodic polarization performance of carbon steel and widen the passive potential region of carbon steel in 55% LiBr ***-Mo inhibitor belongs to anodic *** 55% LiBr solution,the relationship between corrosion current density icorr and corrosion potential Ecorr of carbon steel accorded with the equation lgicorr=-2.66-3.54Ecorr,and the value of cathodic Tafel constant βc for the H2 reaction was 282 *** 55% LiBr solution contained enhanced-Mo inhibitor,a passive film comprising Fe3O4 and MoO2 was formed on the carbon steel surface by electrochemical *** corrosion of carbon steel might be retarded by this protective film,and the anticorrosion performance of carbon steel in 55% LiBr solution might be improved by enhanced-Mo inhibitor.

关键词： corrosion enhanced-Mo inhibitor carbon steel

Trace Element Geochemistry of Magnetite from the Fe(-Cu) Deposits in the Hami Region, Eastern Tianshan Orogenic Belt, NW China

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 176-195页

作者： HUANG Xiaowen qi liang MENG Yumiao State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Laser ablation–inductively coupled plasma–mass spectrometry（LA–ICP–MS） was used to determine the trace element concentrations of magnetite from the Heifengshan, Shuangfengshan, and Shaquanzi Fe（–Cu） deposits in the Eastern Tianshan Orogenic Belt. The magnetite from these deposits typically contains detectable Mg, Al, Ti, V, Cr, Mn, Co, Ni, Zn and Ga. The trace element contents in magnetite generally vary less than one order of magnitude. The subtle variations of trace element concentrations within a magnetite grain and between the magnetite grains in the same sample probably indicate local inhomogeneity of ore–forming fluids. The variations of Co in magnetite between samples are probably due to the mineral proportion of magnetite and pyrite. Factor analysis has discriminated three types of magnetite： Ni–Mn–V–Ti（Factor 1）, Mg–Al–Zn（Factor 2）, and Ga– Co（Factor 3） magnetite. Magnetite from the Heifengshan and Shuangfengshan Fe deposits has similar normalized trace element spider patterns and cannot be discriminated according to these factors. However, magnetite from the Shaquanzi Fe–Cu deposit has affinity to Factor 2 with lower Mg and Al but higher Zn concentrations, indicating that the ore–forming fluids responsible for the Fe–Cu deposit are different from those for Fe deposits. Chemical composition of magnetite indicates that magnetite from these Fe（–Cu） deposits was formed by hydrothermal processes rather than magmatic differentiation. The formation of these Fe（–Cu） deposits may be related to felsic magmatism.

关键词： trace elements magnetite LA–ICP–MS Fe(–Cu) deposits Eastern Tianshan Orogenic Belt Xinjiang

PREPARATION AND CHARACTERIZATION OF INCLUSION COMPLEXES OF TWO-ARM LINEAR AND FOUR-ARM STAR-SHAPED POLY(ε-CAPROLACTONE)S WITHα-CYCLODEXTRIN

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Chinese Journal of Polymer Science 2006年第3期24卷 245-252页

作者： Lu Wang jing-liang Wang 董常明 Department of Polymer Science ＆ Engineering School of Chemistry and Chemical Technology Shanghai Jiao Tong University Shanghai 200240 China

Both four-ann star-shaped poly（ε-caprolactone）（4sPCL） and two-ann linear PCL （2LPCL） were synthesized and their inclusion complexation with α-cyclodextrin （α-CD） were studied. The inclusion complexes （ICs） formed between the PCL polymers and α-CD were characterized by ^1H-NMR, DSC, TGA, WAXD, and FT-1R, respectively. Both branch ann number and molecular weight of the PCL polymers have apparent effect on the stoichiometry （CL：CD, mol：mol） of these ICs. All these analytical results indicate that the branch arms of the PCL polymers are incorporated into the hydrophobic α-CD cavities and their original crystalline properties are completely suppressed. Moreover, the inclusion complexation between two-ann linear or four-ann star-shaped PCL polymers and α-CD not only enhances the thermal stability of the guest PCL polymers but also improves that of α-CD.

关键词： Inclusion complexes Linear poly(ε-caprolactone) Star-shaped poly(ε-caprolactone) Thermal stability.

Estimates for parametric Marcinkiewicz integrals in BMOand Campanato spaces

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Applied Mathematics(A Journal of Chinese Universities) 2011年第2期26卷 230-252页

作者： FANG qi-quan SHI Xian-liang College of Mathematics and Computer Science Hunan Normal University Changsha Hunan 410081China

In this paper, the authors consider the behaviors of a class of parametricMarcinkiewicz integrals μ_Ω~ρ, μ_（Ω,）^（＊,）~ρ_λ and μ_Ω~ρ,S on BMO（Rn） and Campanato spaces with com-plex parameter ρ and the kernel Ω in Llog~＋ L（S^（n-1））. Here μ_（Ω,）^（＊,）~ρ_λand μ_Ω~ρ,S are parametricMarcinkiewicz functions corresponding to the Littlewood-Paley g_λ~＊-function and the Lusin areafunction S, respectively. Under certain weak regularity condition on Ω, the authors prove thatif f belongs to BMO（Rn） or to a certain Campanato space, then [μ_（Ω,）^（＊,）~ρ_λ（f）]~2, [μ_Ω~ρ,_S（f）]~2 and[μ_Ω~ρ（f）]~2 are either infinite everywhere or finite almost everywhere, and in the latter case, somekind of boundedness are also established.

关键词： parametric Marcinkiewicz integrals Campanato space weak Dini-type regularity condition.

Geomorphologic Study of Anhui Section of Changjiang River Using Landsat TM Image

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Chinese Geographical Science 2007年第3期17卷 250-256页

作者： qi Yueming Tan Haiqiao liang Xing Institue of Earth Resources and Geosciences China University of Mining and TechnologyXuzhou221008China Institue of Environment China University of GeosciencesWuhan430074China

Fluvial landforms in the Anhui section of the Changjiang(Yangtze)River are often considered as the main factors for frequent *** is these special landforms that influence the channel changes of the Changjiang *** Landsat TM image of 2000,this paper conducted a series of image processing,including principal component analysis,multi-spectral composition,gray value statistics,and spectral analysis of ground *** it got a new interpretation map of different kinds of fluvial landforms of the Changjiang River in the Anhui *** on the interpretation mentioned above,the paper analyzes the distribution and characteristics of such typical landforms as terraces,floodplains and battures,and their functions on the changes of river *** results show a consistence with the earlier conclusion that the Anhui section of the Changjiang River tends to deflect gradually toward south,which provides more implications for further study on the geomorphologic evolution of the river channel.

关键词： Anhui section of the Changjiang River fluvial landform remote sensing Optimum Index Factor(OIF) Principal Component Analysis(PCA)

Multi-domain Spectral Immersed Interface Method for Solving Elliptic Equation with a Global Description of Discontinuous Functions

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Chinese Journal of Aeronautics 2012年第3期25卷 297-310页

作者： JIANG Yongsong liang An SUN Xiaofeng jing Xiaodong School of Jet Propulsion Beihang University Beijing 100191 China Department of Compressor Design Shenyang Aeroengine Research Institute Shenyang 110015 China AVIC Commercial Aircrafl Engine Co. Ltd. Shanghai 200241 China

This paper presents the extension of the global description approach of a discontinuous function, which is proposed in the previous paper, to a spectral domain decomposition method. This multi-domain spectral immersed interlace method（IIM） divides the whole computation domain into the smooth and discontinuous parts. Fewer points on the smooth domains are used via taking advantage of the high accuracy property of the spectral method, but more points on the discontinuous domains are employed to enhance the resolution of the calculation. Two that the domain decomposition technique can placed around the discontinuity. The present reached, in spite of the enlarged computational discontinuous problems are tested to verify the present method. The results show reduce the error of the spectral IIM, especially when more collocation points are method is t：avorable for the reason that the same level of the accuracy can be domain.

关键词： computational aerodynamics immersed interface method immersed boundary method Chebyshev spectral method domain decomposition method

时空异质性视角下华北地区碳足迹评估及驱动因子分析

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生态经济 2025年第1期41卷 70-79页

作者：袁亮柴林何伟军孔阳祁煜智三峡大学经济与管理学院湖北宜昌443002

碳足迹是衡量碳排放的重要指标,削减碳足迹是实现“双碳”目标的前提条件。华北地区作为我国高耗能、高排放的集中区域,客观量化碳足迹并探究主要驱动因子对加快推进碳减排具有重要意义。为此,论文基于IPCC法对华北地区“十五”至“十... 详细信息

碳足迹是衡量碳排放的重要指标,削减碳足迹是实现“双碳”目标的前提条件。华北地区作为我国高耗能、高排放的集中区域,客观量化碳足迹并探究主要驱动因子对加快推进碳减排具有重要意义。为此,论文基于IPCC法对华北地区“十五”至“十三五”期间的碳足迹进行测算,运用标准差椭圆分析碳足迹的分布及转移特征,使用地理探测器识别碳足迹的主要驱动因子。研究发现:(1)“十五”至“十三五”期间碳足迹总量经历了“先增长—后下降”两个阶段,由“十五”期间的425452万吨上升至1066353万吨,而后逐渐下降到“十三五”期间的898908万吨。(2)标准差椭圆呈稳定的“南—北”分布,重心分布于山西大同和河北张家口之间,呈向西北方向偏移趋势,已偏移72.56千米。(3)能源强度、产业结构、城镇化率对碳足迹驱动因子解释力度较大,且关键交互因子均含有能源强度、产业结构、研发投入。华北地区不同时期碳足迹分布及影响因子存在时空差异,在制定碳减排政策时应充分考虑区域碳足迹的时空异质性。

关键词：碳足迹驱动因子时空特征地理探测器标准差椭圆

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