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The preparation and characterization of a controlled-release multicomponent (NPK) fertilizer with the coating layer consisting of a biodegradable copolymer of poly(butylene succinate) and a butylene ester of dilinoleic acid (PBS/DLA) is reported. The morphology and structure of the resulting polymer-coated materials and the thickness of the covering layers were examined using X-ray diffraction and scanning electron microscopy coupled with energy dispersive X-ray analysis. The mechanical properties of these materials were determined with a strength-testing machine. Nutrient release was measured in water using spectrophotometry, potentiometry, and conductivity methods. The results of the nutrient release experiments from these polymer-coated materials were compared with the requirements for controlled-release fertilizers. A conceptual model is presented describing the mechanism of nutrient release from the materials prepared in this study. This model is based on the concentrations of mineral components inside the water-penetrated fertilizer granules, the diffusion properties of the nutrients in water, and a diffusion coefficient through the polymer layer. The experimental kinetic data on nutrient release were interpreted using the sigmoidal model equation developed in this study.

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Calcination process was investigated on the laboratory scale with the use of hydrated titanium dioxide containing rutile nuclei from the industrial installation (sulfate process). The influence of temperature (750−900 °C) on the anatase−rutile phase transformation and on the crystallites' growth variation was determined. Phosphate, potassium, lithium, and aluminum were introduced into calcination suspension. It was found that whereas an introduction of lithium, in phosphate presence, either increased or stabilized the anatase−rutile transformation degree, the introduction of potassium significantly decreased it. The intensity of these changes depended on both the temperature of the process and on phosphate content. The introduction of aluminum, in constant phosphate presence, had an intermediate influence on the rutilization of anatase between that of either potassium and phosphate on the one hand and lithium and phosphate on the other. Similarly to potassium, aluminum intensified the influence of phosphate but to a smaller degree and only a lower temperature. The introduction of lithium, regardless of whether or not phosphate and potassium were present, increased rutilization degree. This dependence was more clearly seen at lower temperatures of the process. Aluminum, either in constant phosphate and potassium or phosphate and lithium presence, increased the anatase−rutile transformation. The degree of these changes depended on both the presence of modifying agents in their mixture and on the temperature of the process. It was found that the introduction to hydrated titanium dioxide of additives causing an increase in the surface area of TiO2, as a result of limitations of crystallite growth in the calcination process, results in elevation of temperature of the anatase−rutile phase transformation (phosphates, potassium) whereas the introduction of additives that decrease the surface area (crystallite growth) enhances the degree of transformation of anatase to rutile (lithium).

, Physico-chemical properties and possible photocatalytic applications of titanate nanotubes synthesized via hydrothermal method, Journal of Physics and Chemistry of Solids, doi:10.1016Solids, doi:10. /j.jpcs.2009 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. of TNTs synthesized at 140°C was about 2.5 times higher than that generated with use of TiO 2 P25. To the best of our knowledge this is a first report on the photocatalytic generation of hydrocarbons using TNTs in the current state of the art.

The influence of technological parameters like hydrogen pressure, temperature, glycerol concentration in aqueous solution, amount of catalyst, stirring speed, and reaction time on glycerol hydrogenolysis to 1,2‐propanediol over a Cu/Al2O3 catalyst prepared by coprecipitation was investigated. Functions describing the process were glycerol conversion as well as selectivity to 1,2‐propanediol and to by‐products in the liquid and gas phase. The structure and properties of synthesized Cu/Al2O3 were characterized by X‐ray diffraction, energy dispersive X‐ray microanalysis, BET surface area, average pore volume, and pore diameter. Catalyst recycle studies were also performed.