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Young’s modulus needed for realizing a numerical analysis model with finite elements dedicated to studying static strain on an artificial bone, made out of composite material (polyester resin reinforced with fiber glass) is determined, as well as Young’s dynamics modulus needed for analysis through numerical simulation of dynamic strain applied to the same structural element (vibrations, shock). Both in, static and dynamic conditions, two methods are utilized in measuring the materials elastic characteristics. Keywords: Young’s modulus, artificial bone, composite material, numerical simulation

The paper presents the obtaining of new biodegradable plastic materials using collagen hydrolysates. As raw materials, to transform into collagen hydrolysates, untanned leathers’ wastes were used. The influence of chemical structure and ratio of protein material on thermoplastic processing were investigated. The effect of protein material contents on physico – mechanical and biodegradability properties has been evidenced. Keywords: biodegradable plastic materials, collagen hydrolysates, protein material

The objective of this study was to obtain graphene oxide starting from graphite and to covalently functionalize this nanomaterial with Cisplatin. The presence of the drug was pointed out using different methods like FTIR Spectroscopy, X-Ray Photoelectron Spectroscopy (XPS), Thermogravimetric analysis (TGA), RAMAN Spectroscopy, X-Ray Diffraction and Scanning electron microscopy (SEM). Keyword: Graphene oxide, covalent activation, Cisplatin

The study was conducted on a powdery mixture derived from mechanical processing of plastics recovered from the instrument panels of ELVs, which contain varying amounts of polypropylene (PP), acrylonitrile butadiene styrene (ABS), polycarbonate (PC),cardboard, rubber, and other materials. The mixture was deposited on a metallic belt-type electrode that introduced them into an area of high intensity electric field created by a rotating cylindrical electrode, connected to a high voltage supply. This electrostatic separation method in association with classical waste processing techniques is a viable solution for the ELVs recycling industry. Keywords: plastic waste, electric fields, electrostatic measurements, electrostatic processes, electrostatic separation

The paper presents the results by application of one method to study the behaviour of packaging material in contact with food products, using different type of adhesives and different types of films for the package manufacturing. The presented method is based on primary aromatic amine determination using spectrophotometer analyze. Three different types of adhesives and three types of different films were considered for testing the migration of aromatic amines. The test was made in the same conditions for each product. Results are used for selecting optimum for material and technology in packaging of food and drinks products by multi-layer lamination in flexible approach. Key words: packaging material, adhesives, migration limit, aromatic amines, food products

Currently the leather industry has to face very high costs to treat and eliminate wastes. Therefore, the aim is to treat organic waste (protein and cellulose) by biochemical processes in order to be recycled in industry and agriculture. All treatments applied to waste mainly aim at substantially reducing environmental pollution. Worldwide research on leather recycling is directed towards obtaining protein composites by biochemical treatments using microorganisms/enzymes and obtaining protein hydrolysates and protein binders with different uses. Leather, even in the form of waste, is a valuable protein source for many areas: leather industry, automotive industry, agriculture, animal husbandry, pharmaceuticals, cosmetics, etc. Organic biopolymers are a source of raw materials for agriculture, as protein waste composition provides sufficient elements to improve the composition of and remediate degraded soils, and plants can benefit from elements such as nitrogen, calcium, magnesium, sodium, potassium, etc. This paper presents a new pilot-scale technology for biochemical hydrolysis of tannery waste and obtaining protein biocomposites - multicomponent systems of protein and cellulose biopolymers with application in the footwear industry and in agriculture for the remediation of degraded soils. Keywords: biotechnology, protein wastes, cellulose, biopolymer, tannery

The paper presents a study about obtaining materials with prolonged biocidal effect based on styrene-butadiene block-copolymers (SBS) grafted with methacrylic acid (ACM) and coupled with antibiotics from the ampicillin group. The IR spectroscopy and the elemental analysis were used to confirm the structure of SBS block-copolymers grafted with methacrylic acid and of the medical ones. The content of grafted methacrylic acid was about 18.8 % in accordance with the 1,2 enchained butadiene content, proving that the methacrylation polymer-analogous reaction takes place at these pendant vinyl groups of the polybutadiene chain. The concentration of the methacrylic acid-ampicillin pendant group is about 38 % and corresponds to the theoretical calculated one. The antibacterial testing of the synthesized polymers showed that the final reaction product has a relatively high biocidal activity on gram-positive and gram-negative microorganisms. Keywords: styrene-butadiene block-copolymers, methacrylic grafting, polymer with antibiotic effect

In this paper we study the non-uniformity that appears in the composite bars reinforced with fiber glass fabric. We defined a factor which characterizes the non-uniformity from the composite materials. We will give a formula for calculating this coefficient and a formula for the elasticity modulus of the composite bars, with two zones in which the volumetric proportions of reinforcement are different. We compared the theoretical results, which give the values of the uniformity coefficient and elasticity modulus, with experimental results obtained for three sets of samples made from ambresit and reinforced with fiber glass fabric. Keywords: composite materials, non-uniformity coefficient, elasticity modulus

Over the last years the use of bioabsorbable materials in orthopaedic surgery has increased exponentially. One of the first surgical interventions to take benefit from these absorbable materials was the reconstructive surgery for the anterior cruciate ligament (ACL) of the knee, meaning the use of interference screws for the primary fixation of the ligament graft. The aim of this paper is to present the main types of screws of this kind, used in current practice, the preferred manufacturing materials and to evaluate the standard implantation procedures in terms of the stability they ensure to the ligament graft. Keywords: bioabsorbable screws, ACL reconstruction, ligamentoplasty

The present study pursues the influence of polyelectrolytes based on maleic co-polymers with styrene and vinyl acetate under the form of natrium salt, on the colour parameters CIEL*a*b* of the Melana type polyacrylonitrile fibers dyed with Methylene blue. The work is part of a study on the metachromacy of cationic dyestuffs at dyeing the polyacrylonitrile fibres in the presence of cationic polyelectrolytes. The colours attributes are analyzed in terms of the tinctorial conditions: polyelectrolyte character and concentration, dyeing temperature and during time. Keywords: maleic polyelectrolytes, polyacrylonitrile fibres, colour differences, tinctorial parameters, methylene Blue