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Equal Channel Angular Pressing (ECAP) is the most emblematic technique for producing bulk nanostructured materials and ultrafine grained materials (UFG) through severe plastic deformation. In this study, we examined a 6063-T1 aluminum alloy, subjected to ECAP processing at room temperature for one, three, six and nine passes respectively, using a 90° die and the processing route BC. The as-received and ECAP processed samples were firstly analyzed in OES experiments, the accumulated equivalent strain being also estimated based on ECAP die geometry and on the number of passes. All specimens were investigated as well in XRD tests for phase identification. Williamson-Hall method was used for evaluating the crystallite size and the lattice strain. Some correlations with the main processing parameters were also established.

The low biodegradability of petroleum-based plastic materials led to the search for novel biodegradable plastics. In this way, a team of German researchers developed, produced and marketed a material that can help the environment, in terms of 100% biodegradability and renewability, contributing to a more efficient use of resources. The trade name proposed by the team is “liquid wood” and is a high-quality thermoplastic material. It brings together the wood and plastics processing industries, in order to make products with complex design geometry and to process warm material wood (lignin and natural fibers) using the same technique and equipments just like for conventional thermoplastic materials. This paper presents analyses of bending test behavior in case of Arboform L, V3 Nature -“liquid wood” (A-LW) and Arboform reinforced with Aramid Fibers (A-LWAF). The results were compared with technical literature and some plastic materials in case of requirement for greater stiffness of material. Keywords: bending test, Arboform, bending strength, flexural modulus

Metallic iron nanoparticles were synthesized by the hydrazine reduction method in three experimental versions. The average size and particle size distribution obtained by the three versions was determined with a particle size measurement system making use of dynamic light scattering. The presence of the aromatic solvent and anti-caking additive influences the average size and size distribution of the particles. The metallic iron nanoparticles obtained in the three experiments were used in the treatment of waters containing a 6.8 mg/l concentration of hexavalent chromium. Reduction of hexavalent chromium concentrations as well as total chromium, COD and TSS depend on pH and reaction times. Thus, the optimal conditions requires for Cr6+reduction, for obtaining values lower than 0.1 mg/l, are: the pH value of 11, a duration of the process 10 hours. Keywords: nanoparticles, chromium, wastewater, chemical oxygen demand, biochemical oxygen demand

The paper deals with the synthesis of compounds based on standard epoxy resin/ modified epoxy resin with different molar ratios of glycols and with the characterization of cured products to investigate the influence of the addition of various amounts of modified resin on the compound flexibility as compared to standard epoxy resin. Modification of epoxy resins with glycols results in a wide range of specific properties superior to neat epoxy resin. These properties are highlighted by characterizing the products obtained using various types of glycols and different standard resin/ modified resin weight ratios by physical- mechanical analyses and Dynamic Mechanical Analyses (DMA). Keywords: glycol-modified epoxy resins, glass transition, dynamical properties and mechanical properties

This research is based on the study of the chemical polymerization of nanocomposites based conductors polypyrrole PPy(Cl) and the HY Zeolite type Faujasite as reinforcements, at room temperature and atmospheric pressure using FeCl3 as initiator of the reaction and dopant at the same time. After characterization commodity we methods primarily on the polymerization of pyrrole with different molar ratios of [FeCl3] / [Pyrrole] in an aqueous medium, followed by a series of characterizations for the polymers obtained. Won the right ratio was used for the preparation of nanocomposites PPy (Cl) / HY Zeolite. After each synthesis, the developed product is characterized by FTIR, SEM, UV-Vis, XRD, and electrical conductivity in order to confirm the success of the process of synthesis and study their properties to specific applications envisaged. Keywords: nanocomposite, polypyrrole, zeolite HY, conductor polymer

Coatings obtained on cellulose fabrics with nonionic dyes – silica hybrids have been investigated. Composition of the impregnation bath and parameters having a major influence on coloring properties were studied in relationship with washing and light fastness. It was found that cotton can be coated with organic-inorganic nonionic dyes - silica hybrids exhibiting fair washing and light fastness. Properties of the coated materials can be controlled by variation of parameters affecting sol obtaining procedures or impregnation conditions. The presence of only one trialkoxysilane group per chromogen makes the formation of a highly crosslinked silica network to be difficult. The partial condensation of DR1-PTES (Disperse Red 1 dye covalently linked to 3-isocyanatopropyltriethoxysilane) to the stage of oligomeric structures, together with the existence of silanol and unhydrolyzed alkoxysilane groups can explain leaching behavior of the coatings obtained with this type of hybrid materials. Keywords: nonionic dyes, silica hybrids, surface coating, cotton fabrics, sol-gel process

This paper presents the synthesis of some acrylic monomers with pendant carbazole groups. They were copolymerized with N-octyl methacrylate to obtain organic photosensitive materials used in the production of holograms with electrophotographic methods. Keywords: N-vinylcarbazole, N (2-hydroxymethyl carbazole), N-carbazolyl methlacrylate, octylmethacrylate

This paper presents the influence of processing temperatures of high-density polyethylene (HDPE), polymethyl methacrylate (PMMA), polycarbonate and acrylonitrile butadiene styrene blend (PC+ABS) on some mechanical properties when obtained through the injection of items from various industries. The HDPE samples were obtained at the following injection temperatures: 180, 190, 200, 210, and 220°C. The PMMA samples were obtained at the following injection temperatures: 220, 230, 240, 250, and 260°C, and PC+ABS samples were obtained at the following injection temperatures: 230, 240, 250, 260, and 270°C. Determining the mechanical properties was made using determining methods of tensile properties, of Izod impact test, and Shore Durometer hardness test. It was observed in the case of the three analyzed polymers that increasing the processing temperature hardly influences their respective hardness. The Izod shock resistance for the three analyzed polymers decreases along with the increase of the processing temperature by injection. The tensile strength at break is influenced by the processing temperature. The increase of the processing temperatures by injection in the case of the three analyzed polymers leads to the decrease of the tensile strength at break. The lowest values of the tensile strength at break occur at the highest processing temperatures. Keywords: high density polyethylene (HDPE), polymethyl methacrylate (PMMA), acrylonitrile butadiene styrene polycarbonate blend (PC+ABS), tensile tests, Izod impact test, Shore Durometer hardness test

Functionalization of multiwalled carbon nanotubes with carboxyl group (–COOH) and oxaliplatin (OX) was investigated using FTIR spectroscopy, high performance liquid cromatography (HPLC), transmission electron microscopy (TEM), inductively coupled plasma mass spectrometry (ICP-MS). Encapsulation efficiency was computed and in vitro behavior regarding MDA-MB-231 cells was studied. Keywords: carbon nanotubes, oxaliplatin, encapsulation, FTIR, TEM

This paper addresses the theoretical and experimental mechanical properties of specific to monolayer composite plates produced from urban and industrial recycling wastes with elastomeric matrix and fibrous protein reinforcement (leather, textile). Defining the theoretical model of composite material with its structural elements, as well as evaluating physical and mechanical characteristics essential to its default drive to an optimal and efficient design of all products made from such materials. By determining the theoretical and experimental parameters with maximum precision, which affects the properties of the composite structure, it is decided its use in specific technical industrial applications. Keywords: composite material, reinforced lamina, recyclable waste, fibrous material.