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ABSOLUTELY E-PURE MODULES AND E-PURE SPLIT MODULES

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Acta Mathematica Scientia 2011年第1期31卷 207-220页

作者：阎舫宇 department of Mathematics Nanjing University department of Basic Courses China Pharmaceutical University

We first introduce the concepts of absolutely E-pure modules and E-pure split modules. Then, we characterize the IF rings in terms of absolutely E-pure modules. The E-pure split modules are also characterized.

关键词： Absolutely E-pure module E-pure split module IF ring copure flat module

Normal Functions and α-Normal Functions

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Acta Mathematica Sinica,English Series 2000年第3期16卷 399-404页

作者： Yan Xu department of Mathematics,nanjing Normal university,nanjing 210097 P.R.china department of Mathematics Nanjing Normal University Nanjing 210097 P. R. China

This paper has studied two open questions about normal functions due to Lappan,and obtained two corresponding results for α-normal functions.

关键词： Spherical derivative Normal function α-Normal function

Strongly peraluminous granites of Mesozoic in Eastern Nanling Range, southern china: Petrogenesis and implications for tectonics

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Science china earth sciences 2005年第2期48卷 165-174页

作者： SUN Tao, ZHOU Xinmin, CHEN Peirong, LI Huimin, ZHOU Hongying, WANG Zhicheng & SHEN Weizhou department of earth sciences, nanjing university, nanjing 2.0093, china Tianjin Institute of Geology and Mineral Resources, china Geological Survey, Tianjin 300170, china 1. department of earth sciences Nanjing University 210093 Nanjing China 2. Tianjin Institute of Geology and Mineral Resources China Geological Survey 300170 Tianjin China

The strongly peraluminous granites (SPGs) of Eastern Nanling Range (ENR) are a characteristic of all bearing highly aluminous minerals, such as muscovite±AI-rich biotite± tourmaline±garnet, and lack of cordierite. In respect of petrography, geochemistry, Nd isotope, and single grain zircon U-Pb dating, the representative granite bodies of them are studied. The research shows that these granites were emplaced in two stages, namely 228-225 Ma BP and J2-3 159-156 Ma BP, belonging to Indosinian and early Yanshanian periods, respectively, and they have low εNd(t) values (-10.6--11.1), high A/CNK, Rb/Sr ratios and tDM values (1887-1817 Ma), and REE's tetrad effect (TE1,3=1.13-1.34). In comparison with related geology, petrology and chronology of granites in adjacent regions, it is suggested that Indosinian SPGs of ENR formed in the circumstance of post-collisional extension 20 Ma after the major collision of Indosinian Movement (258-243 Ma BP) in Indo-china Peninsula, and early Yanshanian SPGs formed in the background of back-arc extension setting controlled by paleo-Pacific tectonic domain, and J1, the interval of two stages, is the interim from Tethyan to Pacific tectonic domains in South china. These SPGs have similar geological and geochemical characteristics, because they all crystallized from the magma of partial melting of early Proterozoic metasedimentary rocks when the thickened crust (≤50 km) became thinning, decompression, and transmitting of water.

关键词： Nanling Range, strongly peraluminous granite, petrogenesis of granite, South china.

Numerical simulations of magnetic reconnection in the lower solar atmosphere

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Research in Astronomy and Astrophysics 2011年第2期11卷 225-236页

作者： Xiao-Yan Xu 1,2,Cheng Fang 2,Ming-De Ding 2 and Dan-Hui Gao 2 1 Purple Mountain Observatory,Chinese Academy of Science,nanjing 210008,china 2.department of Astronomy,nanjing university,nanjing 2.0093,china Purple Mountain Observatory Chinese Academy of Science Nanjing 210008 China department of Astronomy Nanjing University Nanjing 210093 China

Observations indicate that Ellerman bombs （EBs） and chromospheric microflares both occur in the lower solar atmosphere,and share many common features,such as temperature enhancements,accompanying jet-like mass motions,short life-time,and so *** strongly suggest that EBs and chromospheric microflares could both probably be induced by magnetic reconnection in the lower solar *** gravity,ionization and radiation considered,we perform two-dimensional numerical simulations of magnetic reconnection in the lower solar *** influence of different parameters,such as intensity of the magnetic field and anomalous resistivity,on the results are *** result demonstrates that the temperature increases are mainly due to the joule dissipation caused by magnetic *** spectral profiles of EBs and chromospheric microflares are calculated with the non-LTE radiative transfer theory and compared with *** is found that the typical features of the two phenomena can be qualitatively reproduced.

关键词： Sun: chromosphere-- Sun: photosphere -- Sun: magnetic reconnection-- Sun: numerical simulation

Quantitativ　estructure－activity　relationships　for　studying　alkyl（1－phenylsulfonyl）　cycloalkane－carboxylates

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Journal of Environmental sciences 1996年第2期8卷 157-166页

作者： He Yibing Wang Liansheng (department of Environmental Science and Engineering, nanjing university, nanjing 2.0093, china) department of Environmental Science Nanjing University Nanjing 210093 China

Octanol/water partition coefficients,adsorption coefficients for soils and sediments and acute toxicities to Daphnia magna of 28 alkyl (1-phenylsulfonyl) cycloalkane-carboxylates were measured. These properties were correlated by linear solvation energy relationship (LSER) and chromatographic retention data determined by reverse-phase high performance liquid chromatography (RP-HPLC). The accuracy and range of applicability of these two quantitative structure-activity relationship (QSAR) methods were compared in this paper.

关键词： alkyl (1-phenylsulfonyl) cycloalkane-carboxylates LSER R-PHPLC.

Variation of the Fe/Mn ratio of ferromanganese crusts from the Central North Pacific: implication for paleoclimate changes

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Progress in Natural Science:Materials International 2005年第6期15卷 530-537页

作者： LU Zunli1**, LING Hongfei1*, ZHOU Feng1, JIANG Shaoyong1, CHEN Xiaoming1 and ZHOU Huaiyang2(1. State Key Laboratory for Mineral Deposits Research, department of earth sciences, nanjing university, nanjing 2.0093, china 2. Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, china)department of earth & Environmental Science, university of Rochester State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China department of earth & Environmental Science University of Rochester Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Contents of Fe, Mn and other elements in four ferromanganese crusts recovered from the central North Pacific are analyzed at high depth-resolution by electron microprobe for reconstructing factors controlling their deposition. Manganese (IV) in hydrogenetic ferromanganese crusts is mainly supplied as colloidal precipitates from the Oxygen Minimum Zone (OMZ), which concentrates high amounts of dissolved Mn (II). The iron is derived from carbonate dissolution and silicate particles of eolian dust. An increase in paleoproductivity during cooler climate would potentially lead to a decrease in Mn deposition due to enlargement of the OMZ which has a “temporary storage” effect for Mn. On the other hand, not affected by the OMZ, the iron entering the Fe-Mn crust would likely increase with the eolian dust input and surface productivity at glacial stages. As a result, the increasing Fe/Mn ratio should indicate a cooling climate. This is supported by the following observations. In the profile of the past 1 Ma, the variations of Fe/Mn ratio coincide with benthic oxygen isotope fluctuation in glacial-interglacial cycles. Three episodes with high Fe/Mn ratios, approximately at 2.6, 1.8 and 0.8 Ma, are detected within the past 3 Ma and coincide with major climate transitions and cooling events. The secular evolution pattern of Fe/Mn ratio in the Cenozoic is similar to the Pb isotope evolution which is mainly controlled by eolian dust and related to climate. The Fe/Mn evolution pattern is also broadly consistent with the global deep-sea oxygen isotope records. Therefore, Fe/Mn ratio recorded in the ferromanganese crusts may be a new proxy for climate change.

关键词： Fe/Mn ratio ferromanganese crust central North Pacific paleoclimate.

New progress of lake sediments and environmental changes research in china

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Chinese Science Bulletin 1999年第19期44卷 1744-1754页

作者： WANG Sumin and ZHANG ZhenkeLaboratory of Lake Sediment and Environment, nanjing Institute of Geography and Limnology, Chinese Academy of sciences , nanjing 210008, china department of Geography and Oceanology, nanjing university , nanjing 2.0093 , china Laboratory of Lake Sediment and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China department of Geography and Oceanology Nanjing University Nanjing China

Environmental change recorded by lake sediments is one of the important branches of the past global changes study. The new progress of lake sediments and environmental changes in china since the late 1980s has been comprehensively discussed. The highlights emphasized are Asian paleomonsoon migration reflected by lake level fluctuation, uplift of the Qinghai-Xizang Plateau recorded by lacustrine sediments, saltlake sediments and

关键词： lake sediments environmental change.

Y_CΩ_(2n)are easy terms

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Chinese Science Bulletin 1998年第20期43卷 1707-1709页

作者： ZHAO Xishun 1 and WANG Ju 2 1. department of Mathematics, nanjing university, nanjing 2.0093, china 2. Institute of Software, Chinese Academy of sciences, Beijing 100080, china department of Mathematics Nanjing University Nanjing China Institute of Software Chinese Academy of Sciences Beijing China

For any natural number n≥1, Y CΩ 2n is an easy term; that is, for any λ term M, λβ+Y\-CΩ 2n =M is consistent, where Y C is Curry fixed point combinator, Ω 2n ≡ω 2n ω 2n and ω 2n ≡λ***...x (there are 2n occurrences of x after λx ). This result is a partial solution to Jacopini’s conjecture: Y CΩ n is an easy term for any natural number n≥2.

关键词： λβ-calculus Kuper’s theorem easy term.

Light-induced unconventional Landau levels of ultracold fermions in a trilayer honeycomb lattice

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Science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 321-326页

作者： HOU JingMin department of Physics,Southeast university,nanjing 211189,china 1. department of Physics Southeast University Nanjing 211189 China

The spectrum of cold fermionic atoms is studied in a trilayer honeycomb optical lattice subjected to a perpendicular effective magnetic field,which is created with optical means. In the low energy approximation,the spectrum shows unconventional Landau levels,which are proportional to the 3/2 power of integer numbers. The zoro modes exist and the quasiparticles are chiral. It is also proposed to identify the unconventional Landau levels via probing the dynamic structure factor of the system with Bragg spectroscopy.

关键词： cold atoms trilayer honeycomb lattice unconventional Landau levels