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Reservoirs play an important role in the exploitation and utilization of water resources, and the flood limited water level (FLWL) is a key parameter to balance flood control and conservation in reservoir operation. This study is aimed at joint operation of the reservoir and floodplains to improve floodwater utilization and enhance economic benefits. The net profits, namely the benefits from power generation and water supply minus the losses from the flood volume diverted to floodplains, are set as the objective function. To maximize the net profits, an optimization model is then proposed. Finally, a nonlinear optimization technique, the complex method, is used to find the optimal seasonal FLWL. The China's Danjiangkou Reservoir (DR) is selected as a case study. The results show that the joint use of floodplains enables 2.0 m and 0.5 m increment of FLWLs in summer and autumn, respectively, compared to the conventional FLWLs. Since the increment of the FLWL decreases the reservoir flood storage by 0.44 billion m, the flood volume need to be diverted to floodplains is increased by 0.54 billion m per year. Meanwhile, the power generation and water diversion are increased by 0.59% and 2.99%, respectively. The assurance probabilities of power generation, water diversion and minimum flow are also increased by 1.1%, 0.96% and 0.70%, respectively. As a result, the economic benefits can be increased by 0.037 billion USD per year. It is concluded that the reservoir seasonal FLWL can be improved by joint operation of reservoirs and floodplains, which is able to enhance economic benefits without increasing flood risks. Moreover, the increment of economic benefits could be shared by reservoir managers and residents that live in floodplains. This novel operating approach is helpful to the integrated water resources management. [ABSTRACT FROM AUTHOR]

Abstract: A novel cathode material, lithium decavanadate Li6V10O28 with a large tunnel within the framework structure for lithium ion battery has been prepared by hydrothermal synthesis and annealing dehydration treatment. The structure and electrochemical properties of the sample have been investigated. The novel material shows good reversibility for Li+ insertion/extraction and long cycle life. High discharge capacity (132mAh/g) is obtained at 0.2mA/cm2 discharge current and potential range between 2.0 and 4.2V versus Li+/Li. AC impedance of the Li/Li6V10O28 cell reveals that the cathode process is controlled mainly by Li+ diffusion in the active material. The novel material would be a promising cathode material for Li-ion batteries. [Copyright &y& Elsevier]

Abstract: The attractive feature of one-dimensional inorganic nanomaterials grown on substrate at low temperature is the good adhesion between the deposited material and the substrate. In this work inert salt-assisted route has been extended to prepare Ga2O3 product on bare Si substrate. By using CaF2 powder as a dispersant, the vapor pressure of metallic Ga is increased greatly as compared to its non-dispersed state. This allows for the β-Ga2O3 nanostructures to be formed at a relatively low temperature of 650°C as a result of direct oxidation of the well-mixed metallic Ga and CaF2 powder. This temperature is much lower than the synthetic temperature required in the cases of direct oxidation of metallic Ga as reported by others. The as-prepared Ga2O3 nanowires and nanobelts are characterized by XRD, SEM, EDX, TEM and PL. The vapor–solid growth process was also discussed for the as-prepared Ga2O3 product on Si substrate. The interesting results indicate the wide applications of inert salt-assisted route to vapor growth of other nanomaterials at relative low temperature. [Copyright &y& Elsevier]