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This study reports the preparation of gelatin – poly(vinyl alcohol) / graphene oxide composites by combining ultrasound treatment, freeze-thawing and freeze drying techniques. Characterization results highlight the positive effect of graphene oxide on materials structure, morphology, swelling degree and biodegradation, as well as rheology.

This paper deals with an input oriented method called Ecological Rucksack applied on two materials –corn starch polylactic acid (PLA) granules (bottle grade) and polyethylene terephthalate (PET) granules (bottle grade). We calculated the total mass of material inputs of PLA (from the cradle to the point of sale) and made comparative analysis with PET. Case study results indicate that Ecological Rucksack of PET granules (bottle grade) in terms of its abiotic material and biotic material requirement is about 44% lower than the Ecological Rucksack of corn starch PLA granules (bottle grade).However, PLA has significantly lower water requirement compared to PET. The study has highlighted some limitations of the Ecological Rucksack method arising from the limited data availability and uncertainties associated with its application.

The column type reactors play a particularly important role in the chemical industry and technology, because they are successfully used in most of the industrial processes. The inner stirring may be achieved by different mechanical means or by bubbling a gas. This study presents some aspects regarding the heat transfer for a process performed in an experimental bubble gas column reactor. The process in a bubble column reactor was performed at different conditions regarding: temperature, pressure of the inlet gas, nozzle diameters for the inlet gas, packing material inside the reactor; choosing in the end the most convenient conditions for the process energetic consumption efficiency.

The aim of this study was to obtain an edible film polymer matrix naturally extracted from tubers of Helianthus tuberosus L and biologically active components extracted from the roasted seeds of Vitis vinifera, in order to protect the active components from oxidation reactions during food conservation. The film was prepared by filling technique. It was evaluated the antioxidant activity of the film by means of DPPH (98.7%) technique, solubility water solubility (20.4%) and Isothermal sorption of water by GAB (Guggenheim, Anderson, de Boer) technique resulting a value of water activity of 0.167 and a value monolayer of 0.026 g water/g film. Through these values the resulting film ensure a sound management of the evolution of biological systems from the point of view of their complexity, especially food whose degradation can impact on their safety.

The main goal of this study was to modify halloysite with polyethylene glycol methacrylate and polyethylene glycol dimethacrylate in order to realize some pH sensitive controlled drug delivery systems. The obtained samples were characterized by spectral techniques (FTIR, XPS) and thermal techniques (TGA, DSC). There was also studied the influence of clay type and initial clay amount onto the drug adsorption process within halloysite. The hydrocortisone release profile was also investigated in simulated gastric fluid and simulated intestinal fluid.

At global scale, the trend of developing new thermoresistant polymeric structures, obtained from a mixture of dynamically cured elastomer/plastomer, and compatibility and curing agents, broadens their area of application and leads to greening of their processing technology and qualitative performance. Through dynamic curing and compatibilization, the elastomeric particles disperse more readily in the mixture thus making it possible to develop new innovative materials and techniques. Polymer structures were obtained by extrusion granulation technology, tested physico-mechanically (hardness, elasticity, tensile strength) according to current standards and morphologically by electron microscopy (SEM).

The aim of this work is to examine the role of alloying elements (Cu, Mg, Zn) in the complex reactions occurring in the heterogeneous system Al-Cu-Mg-Zn/K2TiF6/KBF4 at high temperatures. The paper presents theoretical and experimental studies to obtain aluminothermic reactions of composite AA7xxx/TiB2, putting into evidence the thermodynamic calculations and X-ray diffraction resulting compounds.

Batch adsorption of 4-nitrophenol (4-NP) from aqueous solutions on some non-ionic porous copolymers based on the styrene and divinylbenzene was investigated. The adsorption studies were performed as a function of various parameters: contact time, initial concentration of 4-NP solution and adsorbent/adsorbate ratio. Equilibrium and kinetics studies were investigated. Also, from the adsorption data the specific surface area of the polymeric adsorbents has been determined. The results showed that the porous beads prepared in presence of porogen mixture (toluene:gasoline) could have potential applications in the treatment of environmental pollution caused by 4-NP.

The poly(betaines) have been still intensively studied due to them biomedical potential. In the present work, two poly(carboxybetaines) derived from poly(4-vinylpyridine) P4VP that have methylene (P4VPB-1) or ethylene (P4VPB-2) spacer between N+ and COO- groups were investigated in order to evaluate its physico-chemical properties in aqueous salted solutions with NaCl or CaCl2. The values of refractive index increment dn/dc, weight-average molecular weight Mw, hydrodynamic radius Rh, and particle size distribution depend on the solvent type and balance between molecular forces as refractometric and laser light scattering measurements showed.

Aeronautic industry is on the trend of development and more comforts are being incorporated in the aircrafts. On the other hand it is necessary to achieve stringent demand of fuel economy and high performance at low cost. To achieve high fuel economy the aeronautics manufacturers are induced to reduce weight in the possible fields. Light weight composite materials like carbon fiber for the impeller of aerodynamic compressors have been used to achieve the requirements of the aeronautics industry. The paper is focused on the FEM modeling and experimental determination of the two tests of the composite material characteristics used for the impeller of aerodynamic compressors.