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Minimal systems of generators for central division algebra and semi-simple algebra

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Chinese Science Bulletin 1998年第21期43卷 1777-1780页

作者： QIU Qizhang 1 and SUN Ling 2.1. department of Mathematics, wuhan university,{2., china 2. department of Information science, wuhan university,{2., china. department of Mathematics Wuhan University Wuhan China department of Information science Wuhan University Wuhan China

Suppose that F is a field of characteristic zero and (ⅰ) D is a finite-dimensional central division algabra over F; (ⅱ) A is a finite-dimensional semi-simple algabra over F. It is proved that as F-algebras, D and A ... 详细信息

关键词： central division algebra semi-simple algebra generator minimal system of generators.

Joint enhancement of lead accumulation in Brassica plants by EDTA and ammonium sulfate in sand culture

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Journal of Environmental sciences 2002年第2期14卷 216-220页

作者： XIONG Zhi\|ting, LU Ping (department of Environmental sciences,{2., wuhan 430072, china. department of Environmental sciences Wuhan University Wuhan 430072 Chin

When EDTA was added alone in the Pb\|contaminated sand, the plant biomass and the total Pb amount in plant decreased in both species, Brassica pekinensis and B. juncea var. multiceps, though the shoot Pb amount increased. In contrast, when (NH 4) 2.O 4 was added alone in the Pb\|contaminated sand, little effect was observed on the shoot Pb amount, though the root Pb amount was significantly increased in B. juncea var. multiceps. When amending EDTA and (NH 4) 2.O 4 in combination, however, the shoot Pb amount in both species substantially increased, being, on an average, 2.times and 9 times higher than that in EDTA alone or (NH 4) 2.O 4 alone amended treatment, respectively. The two amendments showed antagonism for plant growth, but synergism for Pb bioaccumulation. B. pekinensis showed its highest level of shoot and total Pb amount in the treatment amended with EDTA and (NH 4) 2.O 4 only a half as much as in the other treatments. It is inferred that the mechanisms responsible for the joint\|enhanced Pb accumulation might be concerned with the acidification of the growth medium, cation exchange reaction and relieving EDTA induced toxicity as results by amending ammonium sulfate.

关键词： lead bioaccumulation EDTA ammonium sulfate Brassica

LARGE DEVIATIONS FOR STATIONARY Φ-MIXING SEQUENCES IN τ-TOPOLOGY

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 149-158页

作者： Hu YIJUN department of Mathematics, wuhan university,{2., china. department of Mathematics Wuhan University Wuhan 430072 China

The results of Bryc on large deviations for empirical measures of stationary Φ-mixing sequences are extended. Bryc states his results in the usual weak topology on the space ofprobability measures. In this paper, under somewhat weaker assumptions than those of Bryc,the author extends Bryc's results by taking the finer topology which is generated by the integralsover bounded measurable functions.

关键词： Large deviation Empirical measure Stationary sequence Φ-mixing τ-topology

Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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wuhan university Journal of Natural {2. 2002年第1期7卷 107-112页

作者： Zheng Hua 1 , Du Yu-min 2.1. department of Chemical Engineering, wuhan university of Technology, {2. 430070, Hubei, china 2. College of Chemistry and Molecular sciences, wuhan university, wuhan 430072, Hubei, china wuhan university of Technology Department of Chemical Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization

Large deviation principles for stationary NA sequences

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Chinese Science Bulletin 1998年第7期43卷 536-540页

作者： HU Yijun department of Mathematics, wuhan university,{2., china department of Mathematics Wuhan University Wuhan China

Under general conditions, the large deviation principles for partial sums of stationary NA sequences are proved.

关键词： NA sequence stationary sequence partial sums large deviation principle.

SILYLATION OF CELLULOSE WITH TRICHLOROSILANE AND TRIETHOXYSILANE IN HOMOGENEOUS LiCl/N,N-DIMETHYLACETAMIDE SOLUTION

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Chinese Journal of Polymer Science 2000年第2期18卷 161-168页

作者： Hai-qing Liu Li-na Zhang department of Chemistry, wuhan university,{2., china wuhan Univ Dept Chem Wuhan 430072 Peoples R China

Silyl celluloses (SiC) were prepared by reacting cellulose with chloropropyltrichlorosilane (CPTCSi) and chloropropyltriethoxysilane (CPTESi) in LiCl/N,N-dimethylacetamide (DMAc). The Si content in the silyl cellulose could be controlled by adjustment of the molar ratio of silane and cellulose. FT-IR spectra showed that cellulose was readily reacted with the above two silane reagents, and the reactivity of CPTCSi is higher than that of CPTESi. It was presumed that the reaction process belongs to graft-polymerization. The results of differential thermal analysis (DTA) indicated that the thermostability of the materials produced increased with the increase of Si content in the sample. The acid resistance of the samples SiC in 1 mol/L HCl aqueous solution was improved significantly. When Si content was ca. 2.%, the silyl cellulose has excellent thermostability, hydrophobicity, low density and stability in 1 mol/L HCl aqueous solution, owing to crosslinking of cellulose chain with silane.

关键词： sily cellulose chloropropyltrichlorosilane chloropropyltriethoxysilane LiCl/DMAc thermostability crosslinking

Fabrication of Dense Ultrafine TiAl Alloys by Spark Plasma Synthesis from Mechanically Activiated Powders

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Journal of wuhan university of Technology(Materials Science) 2007年第3期22卷 408-411页

作者：夏力 department of Materials Engineering Wuhan University

Powder of Ti-46at%Al alloy was synthesized through mechanical activation（MA） and then sintered and concurrently consolidated in a short sintering time of 900 s by using a spark plasma sintering（SPS） process. The XRD and SEM profiles show that the microstructures of TiAl alloys contained γ TiAl and small amount α-2.Ti3Al phase, whose amount can be controlled by the sintering temperature. The compacts retained the original fine-grained fully densified bodies by avoiding an excessively high sintering temperature. The alloys sintered at higher temperature with this process showed a coarser microstructure. So it is possible to produce dense nanostructured TiAl alloys by mechanically activated spark plasma sintering （MASPS） within a very short period of time.

关键词： titanium aluminides mechanical activation spark plasma sintering (SPS)

1.55 μm Wavelength Operation of E_r^(3+) -Doped Optical Fiber Bistability

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wuhan university Journal of Natural {2. 1999年第4期4卷 435-438页

作者： SONG Qian 1, ZHANG Yuan cheng 2.1. College of Electronics Information, wuhan university, wuhan 430072,{2. 2. department of Physics, wuhan university, wuhan 430072,{2. wuhan university College of Electronics Information Wuhan China (GRID:grid.49470.3e) (ISNI:***) wuhan university Department of Physics Wuhan China (GRID:grid.49470.3e) (ISNI:***)

An all optical all fiber optical bistability operation has been realized in an all fiber cavity consisted with Er doped fiber and optical fiber loop mirrors. The experimental bistability threshold is consistent w... 详细信息

关键词： optical nonlinearity optical bistability Er doped fiber all fiber device

Large deviations for Glauber dynamics of continuous gas

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Science china Mathematics 2008年第5期51卷 973-986页

作者： SONG QiongXia~(1,2. 1 school of Mathematical sciences,{2. university,{2. 430072,china 2.department of Statistics and Probability,Michigan State university,East Lansing,MI4882.,USA school of Mathematical sciences Wuhan University Wuhan 430072 China department of Statistics Probability Michigan State University East Lansing MI48824 USA

This paper is devoted to the large deviation principles of the Glauber-type dynamics of finite or infinite volume continuous particle systems. We prove that the level-2.empirical process satisfies the large deviation principles in the weak convergence topology, while it does not satisfy the large deviation principles in the τ-topology.

关键词： Gibbs measures Glauber dynamics empirical processes large deviation principles 60J2. 60F10 82.2. 82.2.