Lagrangian relaxation has been widely used in hydrothermal scheduling. Complicating constraints are relaxed by multipliers which are usually updated by a subgradient method (SGM). The SGM suffers from slow convergence caused by the non-differentiable characteristics of dual functions. This paper presents an algorithm that utilizes the Bundle Trust Region Method (BTRM) to update the multipliers ...

Nano-sized BaTiO3 powders with particular Nb concentrations were prepared by Rotary- Hydrothermal (RH) method. Hydrothermal method was used at 180 °C for 5 hours with new Ti pressure and the teflon vessel was rotated at a speed of 160 rpm during the hydrothermal reaction. New hydrothermal method was used instead of previous solid state reaction for the system BaTiO3±Nb<sub...

Nano-sized BaTiO3 powders with particular Nb concentrations were prepared by Rotary- Hydrothermal (RH) method. Hydrothermal method was used at 180 °C for 5 hours with new Ti pressure and the teflon vessel was rotated at a speed of 160 rpm during the hydrothermal reaction. New hydrothermal method was used instead of previous solid state reaction for the system BaTiO3±Nb<sub...

h-zsm-5 nano-zeolites were synthesized by hydrothermal method using tetrapropylammonium hydroxide (tpaoh) as a template in the presence of various tpabr concentrations. the effect of different tpabr/tpaoh molar ratios was studied on the catalytic performance of dehydration of methanol to dimethyl ether (dme) in a fixed bed reactor under the same operating conditions (t=300°c, p=1 atm, and whsv=...

in the present work, we report a suitable approach for the preparation of batio3 nanostructures via the hydrothermal condition using dolapix et85 as surfactant. the powders were investigated by x-ray diffraction (xrd), scanning election microscopy (sem), energy-dispersive x-ray spectroscopy (edax), field emission transmission electron microscopy (fetem), selected area electron diffraction (saed...

Tubular ZnO microstructural arrays were fabricated by a hydrothermal decomposition method. The dependence of the morphologies on the growth time and temperature was investigated in detail. An experiment was carried out to determine the mechanism of tubular ZnO formation. Our results showed that ZnO microtubes originated from an ageing process from ZnO microrods at a lower temperature (compared ...

The present paper presents a facile and low-cost hydrothermal method to synthesize stoichiometric FeNi3 alloy nanoparticles by reducing Ni(NO3)2.6H(2)O and Fe(NO3)2.9H(2)O with hydrazine hydrate in strong alkaline media. X-ray diffraction patterns of as-prepared samples synthesized at 180 degrees C for different hydrothermal reaction times reveal that the products are pure stoichiometric FeNi3 ...

Low-temperature aqueous chemical growth methods have shown great potential in the synthesis of ZnO nanostructures. Hexamethylenetetramine (HMTA) is the most common chemical substance used in the hydrothermal synthesis. In this study zinc oxide nanoparticles were prepared via hydrothermal growth using zinc acetate dihydrate and sodium hydroxide, as precursors instead of HMTA, as it is commercial...

A novel method which is based on the hydrothermal reaction was employed to synthesize LiV3O8. First, the mixture solution of LiOH, V2O5, and NH4OH was subjected to the hydrothermal reaction. The hydrothermal treatment yielded a clear, homogeneous solution. The evaporation of this solution led to the formation of a precursor gel. The gel was then heated at different temperatures in the range of ...

in the present work, the effect of ca(no3)2.4h2o and (nh4)2hpo4 primary solutions as the beginning materials in synthesis of a calcium phosphate phase, was examined. so, we investigated the wet chemical reactions in solution at different temperatures by a hydrothermal condition aimed at hydroxyapatite (ca10(po4)6(oh)2); (hap) synthesis. the powders were investigated by xrd,sem, fe-tem, hrtem, e...