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Oleogels are structured liquid oils with applications in food, cosmetic, and pharmaceutical industries. Structured oils may become alternatives to the commonly used solid fats, such as palm fat or hydrogenated fats. Properties of oleogels are primarily dependent on the structuring agent applied. This paper was intended as an examination of structuring properties and oleogel oil binding capacities of various monomer ingredients (plant and beeswaxes, monoacylglycerol) and comparison of the oleogels produced with palm fat. An oleogel produced with candelilla wax (CLX) exhibited a structure most similar to that of palm fat. These products showed statistically significant differences of colour from palm fat. In addition, textures of the oleogels differed from one another and from palm fat. Oleogel containing rice bran wax (RBX) had the most similar viscosity properties. Oleogels including candelilla wax and yellow bees wax displayed best oil binding structures (assayed by centrifugal and LumiSizer methods). When filtered (at 40°C), on the other hand, minimum oil loss after 24h was demonstrated by the oleogels containing CLX and RBX, possible evidence that these structure-forming substances roduce oleogels that could be used in products exposed to more elevated temperatures. Oleogels may become alternatives to the commonly used solid fats. Thanks to the use of oil structuring agent at the level of 3% liquid oil becomes solid. Using these innovative fat products can stabilize oil in the product, and also it can improve the nutritional value of food products by replacing a popular palm fat rich in saturated fatty acids, which exert an adverse influence on humans’ cardiovascular system, by oils rich in unsaturated fatty acids.

In this paper, optimum hot formation processing parameters for 31VMn12 steel were established, the torsion deformation of 31VMn12 steel was investigated at temperatures from 900, 1000, 11000C and strain rates from 0.05 s-1 to 3 s. –1. There were studied the structural aspects of materials, in microstructures by electronic microscopy. The stress level decreases with increasing deformation temperature and decreasing strain rate, which can be represented by a Zenner-Hollomon parameter. The mathematical model presented in the paper describes the relationship of tension strain, voltage and temperature coefficient 31VMn12 steel at high temperatures. The stress-strain curves determined by the torsion test allowed the calculation of the Zenner–Hollomon parameter corresponding to the maximum stress. By using this parameter has established a set of equations that reproduce completely stress-strain curve, including the hardening, the restoration and dynamic recrystallization area. Comparisons were made between the experimental results and the predicted and confirmed that constitutive equations developed can be used for mathematical modelling and other attempts (forging, compression) and other types of steel.

Breast reconstruction involves two major conditions: to be oncologically safe and to respect the aesthetic of the reconstructed breast. Moreover, every healthcare system in the world manifests a keen tendency to cut back on medical costs, which influences our surgical techniques and breast reconstruction procedures. The use of biological matrices like the acellular dermal matrix has become an acknowledged alternative in implant-based breast reconstruction, in spite of the many impediments and controversies that surround it. However, these matrices are costly and less attainable as compared to synthetic meshes that are conservative with resources and unyielding to the formation of biofilm bacteria. Accordingly, we decided to research the impact of synthetic meshes in implant-based breast reconstruction.

The paper presents the research carried out by our team on achieving amphiphilic polymeric microcomposites, colored in ruby and violet shades for natural fibers dyeing (cotton, wool). The colored polymeric microcomposites were characterized in term of their morpholo- gical (by optical microscopy and SEM analysis) and physicochemical performancies (by FT-IR and UV-Vis spectroscopy, colorimetric analysis). The colored microcapsules were tested by studying the controlled release of the encapsulated dyes in water, to pH variation. This study was necessary to the coloristic characterization of colored polymeric microcomposites to determine the optimal microcapsules dye concentration and dyeing concentration of natural fibers.

In the paper it is presented a new Euler – Bernoulli theory based on an assymetrical distribution of strains towards the median plane, the area subjected to compression has a transversal stretching, while the area subjected to tensile has a transversal contraction. This theory takes into account the transversal contraction factors and consequently the eigenpulsations of bars vibrations with rectangular section depend on the ratio between the bars width and thickness. This theory is experimentally verified for Dammar based composite bars reinforced with cotton, flax, silk and hemp fibers. For the considered bars, we have experimentally determined the eigen frequencies and the damping factor values.

The selective collection of plastic, paper, glass and metal waste represents a desirable behavior in any civilized community with environmental concerns. The collection and recovery of recyclable materials is also a concern for the city of Arad, the purpose of this study being that of identifying the strengths and weaknesses of selective waste collection at the level of this urban community. Starting from the premise that responsible behavior in terms of waste and its collection is an important factor in the ecological development of a community, the present article aims to explore the local realities in this regard, to diagnose the state of things, as it is at present, in the city of Arad. We have highlighted and recorded the population’s existing mentalities and perceptions, the citizens’ expectations from the local authorities, in order to provide optimal intervention opportunities to increase control for a better management of selective collection.

In the paper, are studied the effects of three acids (sulfuric, nitric and hydrochloric) in concentrations of 10% and 20% on the composite materials (type resins reinforced with fiberglass). These composite materials are obtained manually and lends itself to getting various containers (for water for example), but can be obtained containers for temporary storage of acids. Certain composite materials with various combinations of fiberglass with a precise number of layers can be used for temporary storage of acids as a result of experimental research made in these paper are also given.

Polymeric bio-composites have special characteristics and use in various areas such as: automotive, aviation and aeronautic industries, civil engineering and for medical devices manufacturing. This paper presents the evaluation of impact behaviour of some types of materials suitable for orthopaedic use. As composites behave very differently at different rates of loading, static strength tests cannot be used to predict impact behaviour in the perspective of prosthetic medical devices study and manufacture. The used testing machine is Instron Dynatup Impact System with Data Acquisition and Control, model 8200, with assisted system of data acquisition and control.

The Pelton turbines convert hydraulic energy into mechanical energy, through the Pelton runner, by using high heads and small discharges. The runner has a complex geometry, described in drawings by transversal and longitudinal sections that form continuous surfaces. The SolidWorks software was used to design two Pelton runners: the R1 runner with 21 buckets and the R2 runner with 19 buckets. The runners were made of polymeric materials through the Rapid Prototyping process, using the Objet Desktop 3D printer, which is based on the Objet PolyJet technology, with a layer thickness of 28 microns [1]. The runners were used to measure the hydrodynamic characteristics of a Pelton microturbine on a test rig. The paper aims to highlight the advantages of the Rapid Prototyping process compared to the traditional technology used to manufacture Pelton runners that are intended for experimental research.

Polyethylene (PE) insulations have a wide applicability in the insulation of both underground pipelines and underground power cables. In this context, by coupled techniques of thermal analysis (TG/DTG+DTA) and microbiological determinations, have been studied thermooxidability and resistance to moulds action of some polyethylene sorts. Following the processing of the experimental data obtained by thermal analysis it was found that during the applied heat treatment (100 oC), in the first approx. 380 h, there is a growth of LDPE (low density polyethylene) polymerization degree by elongation of the aliphatic chains, after which the predominant process consists in the structure crosslinking. For MDPE (mean density polyethylene) samples, during the thermal treatment applied, it was found that the crosslinking degree of polyethylene (PE) increased without significant molecular weight change (with all the related consequences of increasing the weight of the tertiary and quaternary carbon atoms in the molecule). Microbiological determinations have highlighted that the resistance to filamentous fungal action of LPDE is higher than that of the investigated MDPE. It was found that after heat treatment applied (1000 h & 100 oC), both at LDPE and at MDPE, decreases the resistance to moulds action is decreased. It has also been found that moulds action resistance is substantially decreased when inoculated culture media and PE samples are exposed to an alternative electric field of 50 Hz – 6 Vrms/cm.