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RECONSTRUCTION OF PRECIPITATION SERIES AND ANALYSIS OF CLIMATE CHANGE OVER PAST 500 YEARS IN NORTHERN china

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Journal of Hydrodynamics 2005年第6期17卷 737-745页

作者： RONG Yan-shu TU Qi-pu College of water resources and Environment Hohai University Nanjing 210098 China tianjin institute of Meteorological Science Tianjin 300074 China Nanjing University of Information Science and Technology Nanjing 210044 China

It is important and necessary to get a much longer precipitation series in order to research features of drought/flood and climate change. Based on dryness and wetness grades series of 18 stations in Northern china of 53. years from 1470 to 2002, the Moving Cumulative Frequency Method （MCFM） was developed, moving average precipitation series from 1499 to 2002 were reconstructed by testing three kinds of average precipitation, and the features of ell mate change and dry and wet periods were researched by using reconstructed precipitation series in the present paper. The results showed that there were good relationship between the reconstructed precipitation series and the observation precipiration series sincc 1954 and their relative root mean-square error were below 1.89%, that the relation between reconstructed series and the dryness and wetness grades series were nonlinear and this nonlinear relation implied that reconstructed series were reliable and could became foundation data for researching evolution of the drought and flood. Analysis of climate change upon reconstructed precipitation series revealed that although drought intensity of recent dry period from mid- dle 1970s of 20th century until early 21st century was not the strongest in historical climate of Northern china, intensity and duration of wet period was a great deal decreasing and shortening respectively, climate evolve to aridification situa- tion in Northern china.

关键词： reconstruction series dryness and wetness grades series precipitation series climate change Northern china

Effect of Sn^(4+) B-Site Substitution on the Microstructure and Dielectric Properties of Ba(Mg_(1/3.Ta_(2/3.)O_3.Microwave Ceramics

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Journal of Materials Science & Technology 2005年第5期21卷 773-775页

作者： Shunhua WU Guoqing WANG, Shuang WANG and Dandan LIUinstitute of Electronics and Information Engineering, tianjin University, tianjin 3.0072,{3. institute of Electronics and Information Engineering Tianjin University Tianjin 300072 China

The effect of Sn^4＋（BaSnO3. B-site substitution on the microstructure and dielectric properties of Ba（Mg1/3.a2/3.O3.microwave ceramics was investigated. X-ray diffraction shows that a complex perovskite material Ba（Mg1/3.a2/3.O3.was prepared. As Sn^4＋ content x increases in the （1-x） Ba（Mg1/3.a2/3.O3.xBaSnO3.（x=0.00～0.20） system, the dielectric constant generally keeps unchanged, while TCF changes from positive to negative. Although the addition of Sn^4＋ reduces the ordering degree, Q f0 is still increased when the ceramics density increases. This trend implies that Q f0 of this system is mostly determined by ceramics density rather than ordering degree. After sintering at 1500℃ for 3.h, the system with x=0.15 was found to have excellent dielectric properties as follows：ε≈25, Q f0≥3.0,000 GHz at 7 GHz, TCF=-0.6×10^-6/℃.

关键词： Ba(Mg1/3.a2/3.O3 Complex perovskite Microwave Dielectric properties

Phase Structure and Dielectric Properties of Doped BaTiO_3.Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2007年第3期22卷 522-525页

作者：李媛 institute of Electronics and Information Engineering Tianjin University

The effects of two rare earth oxides such as CeO2 and Sm2O3.on the phase structure and dielectric properties of BaTiO3.ceramic were investigated. Results indicate that the dielectric constant of this system will increase greatly with the increasing content of these two oxides, and Ce^4＋ substitutes for Ba^2＋ located at A-site in ABO3.structure. Quantitative XRD analysis shows that c/a ratio in the sample with addition of CeO2 will increase, which implies the increase of tetragonality in system, causing the augment of dielectric constant, and the decrease of the crystal＇s geometrical symmetry results in curie-temperature moving towards low temperature; Sm^3.（0.096 nm） substitutes for Ba^2＋（0.13. nm） possessing larger radius in A-site and the electrovalency in A-site increases, the mutual effect is strengthened, so the polarization is enhanced, and the dielectric constant increases notablely.

关键词： BaTiO3 dielectric properties additive CeO2 Sm2O3

The possible contribution of a mantle-derived fluid to the Ningwu porphyry iron deposits—Evidence from carbon and strontium isotopes of apatites

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Progress in Natural Science:Materials International 2008年第2期18卷 167-172页

作者： Jinjie Yu ,Jingwen Mao,Changqing Zhang institute of mineral resources,Chinese Academy of Geological Science,Beijing 10003.,{3. institute of mineral resources Chinese Academy of Geological Science Beijing 100037 China

Apatite is a characteristic mineral for the iron deposits in the Ningwu region. Apatite shows a range of d13.PDB values from à9.6& to à0.6&,and most of them with the d13.PDB values distributed in a range of mantle carbon (i.e.,à2& to à9&),except for samples T-06-1 and J-06-3. Apatites in the Ningwu porphyry iron deposits yield a narrow variation range of 87Sr/86Sr values from 0.7063.6 to 0.707577,similar to those of the volcanic and subvolcanic rocks and higher than that of a typical mantle-derived magmatic apatite (i.e.,about 0.7040),indicating that formation of the apatites was involved with crust material contamination. d13.PDB and 87Sr/86Sr values of the apatite indicate a possible contribution of mantle-derived fluid and material to formation of the Ningwu porphyry iron deposits,supported by regional geology,regional gravities and geochemistry of the volcanic and subvolcanic rocks in the Ningwu region.

关键词： Apatite 87Sr/86Sr ratios Fluid inclusion d13. Mantle fluid and material

An approach to 3. NURBS modeling of complex fault network considering its historic tectonics

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Progress in Natural Science:Materials International 2006年第5期16卷 546-553页

作者： ZHONG Denghua, LIU Jie and LI Mingchao (School of Civil Engineering, tianjin University, tianjin 3.0072, china) School of Civil Engineering Tianjin University Tianjin 300072 China

Fault disposal is a research area that presents difficulties in 3. geological modeling and visualization. In this paper, we propose an integrated approach to reconstructing a complex fault network (CFN). Based on the non-uniform rational B-spline (NURBS) techniques, fault surface was constructed, reflecting the regulation of its spatial tendency, and correlative surfaces were enclosed to form a fault body model. Based on these models and considering their historic tectonics, a method was put forward to settle the 3. modeling problem when the intersection of two faults in CFN induced the change of their relative positions. First, according to the relationships of intersection obtained from geological interpretation, we introduced the topological sort to determine the order of fault body construction and rebuilt fault bodies in terms of the order; then, with the disposal method of two intersectant faults in 3. modeling and applying the Boolean operation, we investigated the characteristic of faults at the intersectant part. An example of its application in hydropower engineering project was proposed. Its results show that this modeling approach can increase the computing efficiency while less computer memory is required, and it can also factually and objectively reproduce the CFN in the engineering region, which establishes a theoretical basis for 3. modeling and analysis of complex engineering geology.

关键词： fault network NURBS technique historic tectonics topological sort 3. modeling.

THE EFFECT OF RECLAMATION IN AREAS BETWEEN ISLANDS IN A COMPLEX TIDAL ESTUARY ON THE HYDRODYNAMIC SEDIMENT ENVIRONMENT

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Journal of Hydrodynamics 2010年第3期22卷 338-350页

作者： LI Meng-guo Key Laboratory of Engineering Sediment of Ministry of Transport Tianjin Research Institute of Water Transport Engineering Tianjin 300456 China

The Oujiang Estuary is a very complex tidal estuary with many islands, which is located in Zhejiang Province, china. Reclamation of areas between islands will create a great amount of land. In this article, the feasibility of reclamation of areas between Lingkun Island and Niyu is studied from the angle of its impacts on the hydrodynamic sediment environment. First, the natural hydrodynamic and sediment conditions and the seabed evolution are analyzed according to in-situ data. Second, numerical models of tidal current and sediment movement under the combined action of wave and current are set up with irregular triangular grid to carry out numerical simulations. The following conclusions are drawn from the study. （1） The areas between Linkun Island and Niyu are not a tidal passage. Wenzhou Shoal has been aggraded gradually, a condition favorable for reclamation. （2） The reclamation is feasible as far as its effect on surrounding hydrodynamic sediment environment is concerned. （3. The reclamation has great favorable socio-economic impacts.

关键词： the Oujiang Estuary tidal current numerical model numerical simulation Wenzhou Shoal reclamation

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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Chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of mineral resources Exploration , Chinese Academy of Sciences , Beijing 100101, china 2. {3. of geology , Chinese Academy of Sciences , Beijing 100029, china 3. {3. of High Energy Physics , Chinese Academy of Sciences , Beijing 100817 , china 4. Beijing University of Science and Engineering , Beijing 100083. china Corresponding author The Research Center of mineral resources Exploration Chinese Academy of Sciences Beijing China institute of geology Chinese Academy of Sciences Beijing China institute of High Energy Physics Chinese Academy of Sciences Beijing China Beijing University of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

Estimates of Central Moments for One Kind of Exponential-Type Operators

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Transactions of tianjin University 2011年第2期17卷 85-88页

作者：宋占杰杨振东叶培新 School of Sciences Tianjin University institute of TV and Image Information Tianjin University School of Mathematics and LPMC Nankai University

In this paper,the explicit estimates of central moments for one kind of exponential-type operators are *** estimates play an essential role in studying the explicit approximation properties of this family of *** the proposed method,the results of Ditzian and Totik in 1987,Guo and Qi in 2007,and Mahmudov in 2010 can be improved respectively.

关键词： exponential-type operator central moment approximation property Stirling series

Lipschitz functions on Banach spaces which are actually on Asplund spaces

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Chinese Science Bulletin 1997年第24期42卷 2051-2054页

作者： CHENG Lixin Shi ShuzhongNankai institute of Mathematics, Nankai University, tianjin 3.0071, china Nankai institute of Mathematics Nankai University Tianjin China

SINCE Namioka and Phelps, starting with Asplund’s pioneering work, introduced the no-tion of Asplund spaces (those are Banach spaces on which every continuous convex function isFrechet differentiable on a dense G_δ subset) and proved that the dual of an Asplund space hasthe Radon-Nikodym property (RNP), the study of differentiability properties of functions oninfinite dimensional spaces has continued widely and deeply (see, for instance, Phelps andGiles). The research attained a great achievment after Stegall’s theorem: If the dualspace E~* has the RNP, then E is an Asplund space. Because of the N-Ph-S theorem, we

关键词： mathematics Lipschitz function Radon-Nikodym property subdifferential Banach space.