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This paper deals with the analysis of temperature effect over the viscosity of the polymeric mixtures used in plastination studies. Two reaction mixtures were prepared respecting the standard protocol of the Biodur S10/15 technique. For these two mixtures, viscosity measurements were performed at -25 °C, +20 °C and +40 °C, after one day, one week, two weeks, three weeks and four weeks, respectively after preparation. These parameters were chosen rationally, since the standard impregnation time for the cold silicone method is three weeks. These results were also corroborated to the acetones’ vapor pressure, showing that for Biodur silicone, impregnation at room temperature is possible. A maximum of two weeks of impregnation was determined for S10, while for S15, this could be realized over a period of three weeks. Keywords: silicone viscosity, impregnation, S10/S15 technique, room temperature, cold method plastination

In this paper, were determined the mechanical properties for Dammar based composite materials. For the begining, were determined the mechanical properties (elasticity modulus, breaking strength, breaking elongation, transversal Poisson ratio) for samples made from a resin whose Dammar is its main part. Based on this resin, were made composite materials, using as reinforcement fabrics from cotton, silk, flax and hemp. For each composite type were experimentally determined the same mechanical properties as in the case of resin based samples. Keywords: textile composites, mechanical properties, stress/strain curves, elastic properties, fractography

On a total of 150 renal corrosion casts with a single renal artery, the artery of superior segment was examined. Three morphological types have been highlighted: Type I, in which the superior segmental artery originating directly in the trunk of the renal artery (8.67% of cases); Type II, in which the superior segmental artery arises from the anterior branch of the renal artery (81.33% of cases); Type III, in which the superior segmental artery arises from the posterior branch of the renal artery (10% of cases). In 78% of cases, the superior segmental artery arises independently from the trunk or renal artery branches (anterior or posterior). In 22% of cases, the superior segmental artery realizes a common trunk with one or more other segmental arteries. Knowledge of these aspects is important both to investigate morphological imaging and performing partial resection of the renal parenchyma. Keywords: kidney; corrosion casts; superior segmental artery; variations

Dental composites, some of the most used materials in the last decade, have been and still are the focus of the researches in the last period of time. The present study aims to evaluate three of the most used composites given their different behaviour in practice. There were performed: the flexural strength test, the compression strength and resistance test at diametral compression according to ADA Sp.27/1993 specification. The results were surprising given the differences between the values obtained for the samples of each material. The study concludes that the variable properties of the composites in the same conditions originate from their inconstant microscopic structure. Keywords:dental composites, flexural strength test, compression strength, esistance test

Membrane processes are a way to remove unwanted elements from wastewater stream. The permeability is an important parameter to filter wastewater and membrane fouling is of great interest in membrane filtration because reduce wastewater flow through the membrane. In order to improve the filtration process, many studies have investigated the use of nanoparticles added in the polymeric membranes and how much influence the permeation properties of membranes. A variety of nanoparticles have been used to modify polymer membranes, such as Al2O3, SiO2, TiO2, ZrO2, Fe3O4, Ag. Nanoparticles are used to improve the properties of membranes like hydrophilicity, permeability and fouling resistance. This paper shows the influence of the TiO2 nanoparticles with a concentration of 0.125 wt.%, on the permeation properties and dyes rejection of the PES and PSf membranes and makes a comparison with the results obtained by other authors. Keywords: TiO2 nanoparticles, PES, PSf, membranes

Respiratory movements monitoring is critical in ensuring optimal patient supervision, especially in critical cases and also in diagnosing sleep apnea syndrome.The aim of our paper is to assess the possible role of magnetic impedance (MI) effect in respiratory movements recording.The study was carried out on 6 volunteers using a special mat equipped with quasi-non-contact MI sensors. Evaluation consisted in monitoring and recording the amplitude and frequency of the respiratory movements during normal breathing and while performing Valsalva maneuver.The constancy of pattern and amplitude of waves recorded suggests that this kind of respiratory movement monitoring may have considerable clinical application in monitoring critical patients and also sleep disorders, especially for children suspected of sleep apnea. Keywords: Amorphous Ferromagnetic Materials, Magneto impedance, Sensor, Breathing, Apnea

The aim of this study was to point out the effect of porous clay heterostructure (PCH) and polymer concentration on thermal and dynamic mechanical properties of Sodium Alginate (SA) based hybrid films. New hybrid films based on SA and PCH were prepared by solvent casting method using different polymer concentrations and clay loadings. The interactions between nanofiller (PCH) and polymer matrix (SA), thermal stability and dynamic mechanical properties of neat SA and hybrid films were evaluated by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The obtained results showed the influence of PCH within SA on the storage modulus and a moderate change of thermal stability, the glass transition temperature being also recorded. The concentration of SA solution and PCH are significant factors which affect the thermal and mechanical properties of hybrid films. Keywords: sodium alginate, porous clay heterostructures, hybrid films, thermal stability, dynamic mechanical analysis

This study aims to reintroduce the economic circuit of recovered uncontaminated with organic impurities polypropylene sorts, the melt alloying of polyolefin with styrene-isoprene block copolymers. Keywords: styrene-isoprene block-copolymers, recycling waste polypropylene, melt alloying

Protonation, quaternization and addition reactions of poly(N-vinylimidazole) to the imidazole nitrogen atom in the position 3 to obtain the corresponding ionic derivatives were studied by NMR spectroscopy. Information and data on the reaction type and product microstructure are presented. The chain tacticity is a special structure aspect which was in detail studied by means of proton and carbon NMR spectra confirming that the chain configuration is not modified by any of the three polymer-analogous reactions. Keywords: poly(N-vinylimidazole); polyelectrolytes; benzyl chloride; trifluoroacetic acid; acrylic acid; chain tacticity; polymer microstructure

Polyurethanes (PU) are synthetic materials with large structural possibilities and mechanical adaptability that have promising perspectives in medical applications. This paper is focused on the hydrolytic stability and biocompatibility of poly(ester-urethane) and poly(ether-urethane) membranes blended with hydroxypropylcellulose (HPC). FTIR analysis and extended biocompatibility tests were performed. Based on our in vitro results this PU sample is expected to promote a better biological tolerance and lower pro-inflammatory reaction in vivo. Keywords: HPC-modified polyurethanes, hydrolytic stability, cytotoxicity, pro-inflammatory potential