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Taking the width/depth ratio of a river channel as an independent variable, a variational analysis of basic flow relationships shows that alluvial-channel flow adjusts channel geometry to achieve stationary equilibrium when the condition of maximum flow efficiency (MFE) is satisfied. As a test of the veracity of MFE and to examine if this theory of self-adjusting channel morphodynamics can be practically applied to large river systems, this study examines the degree of correspondence between theoretically determined equilibrium channel geometries and actual measurements along the middle and lower Yangtze River. Using four different forms of the Meyer-Peter and Muller bedload relation and relations of flow continuity and resistance we show that the Meyer-Peter and Muller bedload relation modified on the basis of MFE theory predicts channel dimensions most accurately when applied to the middle and lower Yangtze River. This provides convincing evidence supporting MFE equilibrium theory . Copyright (c) 2014 John Wiley & Sons, Ltd.

A series of new complexes of poly(styrene-co-methacrylic acid) with Ln(III) (Ln = La, Eu, Tb) were synthesized and well characterized by means of elemental analysis, FTIR, differential scanning calorimetric (DSC) analysis, TG-DTA analysis, X-ray diffraction (XRD), and fluorescence determination. The elemental analysis and FTIR studies showed that a large part of carboxylic groups on the side chain of the copolymer are coordinated with Ln(III) ions. The TG-DTA and DSC analysis results indicated that the complexes have good thermal stability. XRD experiments showed that copolymers and the complexes are amorphous. Among these complexes, Eu(III) complexes and Tb(III) complexes exhibit characteristic fluorescence with comparatively high brightness and good monochromaticity. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 3388-3394, 2009