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The Ground and Excitation Levels of the Trimer

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wuhan university Journal of Natural Sciences 1998年第2期3卷 163-164页

作者： You Pu(department of physics, wuhan university, wuhan 430072.china) wuhan university Department of Physics Wuhan China (GRID:grid.49470.3e) (ISNI:***)

The ground and excited levels of the trimer (4He)3 are obtained theoretically by solving the 2-D Faddeev integral equation in the momentum space. In solving the equation, the direct matrix inversion method (I. M.) is used instead of the iteration and Pade approximate method. The new HFD-B Aziz potential ν is used in the calculation.

关键词： Trimer Faddeev equation matrix inversion method

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, wuhan 430072. 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.

THE NON-DIFFERENTIABILITY OF A CLASS OFFRACTAL INTERPOLATION FUNCTIONS

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Acta Mathematica Scientia 1999年第4期19卷 425-430页

作者：陈世荣 wuhan Univ Dept Phys Wuhan 430072 Peoples R China

Hardin and Massopust([1]) introduced a class of fractal interpolation functions and calculated their Bouligand dimensions. This paper deals with the non-differentiability of these functions and shows some conditions under which they are nowhere differentiable. The basic technique here is based on the presentation the author obtains.

关键词： fractal interpolation iterated system nowhere differentiablity Hausdorff metric

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, wuhan 430072. 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. 20%, 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

A PRICE-SETTING NEWSVENDOR MODEL UNDER CVAR DECISION CRITERION WITH EMERGENCY PROCUREMENT

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Journal of Systems Science and Systems Engineering 2010年第1期19卷 85-104页

作者： Minghui XU School of Economics and Management,wuhan university,wuhan 430072.china School of Economics and Management Wuhan University Wuhan China

In this paper, we consider a newsvendor model in which a risk-averse manager faces a stochastic price-dependent demand in either an additive or a multiplicative form. An emergency purchase option is allowed after the realization of demand to satisfy the units that are short. By adopting Conditional value-at-risk （CVaR） as the decision criterion, we aim to investigate the optimal pricing and ordering decisions, and the effects of parameter changes in such a setting. We provide sufficient conditions for the uniqueness of the optimal policy for both demand models. We perforl~, comparative statics analysis to show how the optimal pricing and ordering decision behaves when changing parameters. We also compare our results with those of the newsvendor with a general utility function and with CVaR criterion under lost sales assumption. Our key results include：（i） For both demand models, the optimal selling price is decreasing in risk aversion. Hence, the optimal price of a risk-averse newsvendor is not greater than the optimal price of a risk-neutral newsvendor. （it） In contrary to the lost sales case, for the multiplicative demand model, the optimal order quantity may not be monotonic in risk aversion. Consequently, the optimal risk-averse order quantity may be lower or higher than the optimal risk- neutral counterpart. （iii） For the additive model, the optimal order quantity is strictly increasing in the emergency purchase price, while for the multiplicative model the optimal order quantity has no such a monotonic property. Some numerical examples are conducted to verify our claims and gain more insights about the risk-averse decision-making behaviors.

关键词： Newsvendor model inventory pricing risk aversion conditional value-at-risk

SOLUTION PROPERTIES OF ANTITUMOR CARBOXYMETHYLATED DERIVATIVES OF α-(1→3)-D-GLUCAN FROM GANODERMA LUCIDUM

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Chinese Journal of Polymer Science 2001年第3期19卷 283-289页

作者： Li-na Zhang Mei Zhang Jing-hua Chen Fan-bo Zeng department of Chemistry wuhan university, wuhan 430072. china Pharmacy College, Tongji Medical university, wuhan 430072. china wuhan Univ Dept Chem Wuhan 430072 Peoples R China Tongji Med Univ Coll Pharm Wuhan 430072 Peoples R China

Fractions of a water insoluble α-(1→3)-D-glucan (GL) extracted from Ganoderma lucidum were carboxy-methylated (CM) to obtain water-soluble carboxymethylated derivatives (CM-GL) having a degree of substitution (DS) of0.38～0.51. Weight-average molecular weight M_w and intrinsic viscosity [η] of the samples CM-GL were measured by gelpermeation chromatography combined with laser light scattering (GPC-LLS) and viscometry. The CM-GL exhibits a stifferchain in aqueous solution at 25℃ than the original glucan, The antitumor activities against Ehrlich ascites carcinoma (EAC,5×10~6) of the carboxymethylated derivatives from the α-glucan and curdlan, a β-glucan, are significantly higher than thoseof the original glucans. The effects of the relatively low molecular weight, expanded chains and better water-solubility of theCM-GL on the enhancement of antitumor activity could not be neglected. The chain stiffness decreased speedily withincrease of temperature from 40 to 60℃ or NaOH concentration from 0.1 to 0.4 in the solution, respectively, and the changeof the chain stiffness is reversible.

关键词： Solution properties Antitumor activity Carboxymethylated derivative α-D-glucan Ganoderma lucidum

PROGRESSING WAVE SOLUTIONS TO QUASI-LINEAR SYSTEMS MIXED PROBLEMS

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Chinese Annals of Mathematics,Series B 1994年第4期15卷 401-420页

作者： WANG WEIKE(department of Mathematics,wuhan university,wuhan 430072.china.) wuhan UNIV DEPT MATHWUHAN 430072PEOPLES R CHINA

The author studies the technique of paradifferential operator defined on a space of conormaldistribution with three indeces,and then use this technique to prove that a progressing wavewhich hits the boundary is reflec... 详细信息

关键词： Quasi-linear system Mixed problem Conormal distribution Tangential Paradifferential operator Reflection of progressing wave.

Weak martingale Hardy spaces and weak atomic decompositions

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Science china Mathematics 2006年第7期49卷 912-921页

作者： HOU Youliang & REN Yanbo School of Mathematics and Statistics, wuhan university, wuhan 430072. china department of Mathematics & physics, Henan university of Science and Technology, Luoyang 471003, china 1. School of Mathematics and Statistics Wuhan University Wuhan 430072 China 2. department of Mathematics & physics Henan University of Science and Technology Luoyang 471003 China

In this paper we define some weak martingale Hardy spaces and three kinds of weak atoms. They are the counterparts of martingale Hardy spaces and atoms in the classical martingale Hp-theory. And then three atomic decomposition theorems for martingales in weak martingale Hardy spaces are proved. With the help of the weak atomic decompositions of martingale, a sufficient condition for a sublinear operator defined on the weak martingale Hardy spaces to be bounded is given. Using the sufficient condition, we obtain a series of martingale inequalities with respect to the weak Lp-norm, the inequalities of weak (p ,p)-type and some continuous imbedding relationships between various weak martingale Hardy spaces. These inequalities are the weak versions of the basic inequalities in the classical martingale Hp-theory.

关键词： martingale, weak Hardy space, weak atom, atomic decomposition.

ON THE METHOD OF SOLUTION FOR A KIND OFNONLINEAR SINGULAR INTEGRAL EQUATION

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Acta Mathematica Scientia 2004年第3期24卷 507-512页

作者： LuJianke departmentofMathematics WuhanUniversityWuhan430072China

The solutions of the nonlinear singular integral equation , t 6 L, are considered, where L is a closed contour in the complex plane, b ≠ 0 is a constant and f(t) is a polynomial. It is an extension of the results obt... 详细信息

关键词： Singular integral equation with Cauchy kernel Riemann boundary value problem with square roots modified principal part Plemelj formula