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Soil contamination is a component that contributes to the increase of environmental pollution, as soil is the key element that underpins food production for household consumption. The transfer of contaminants from soil to plants is one of the input mechanisms of human exposure to metals through food chain. Mathematical models are documented as effective tools, that could help observe pollutants impact on agricultural products (vegetables and fruits) as well as on environmental systems, to evaluate different scenar...

The aim of the study was to investigate the effect of microcrystalline cellulose fibers on the mechanical properties of flexible starch based foams. During the experiment the foams obtained with potato starch with the addition of glycerol as plasticizer were tested. The starch was blended with glycerol in laboratory mixer with 30 wt.% glycerol addition. The process of making foams have been carried out by microwave heating in laboratory microwave oven. To improve the mechanical properties of starch foams to the mi...

The study solves actual modern problem for obtaining polysilicate solution (as a mineral component of clinkerless binder) based on low-quality siliceous raw materials. A mechanochemical synthesis method of sustainable colloidal silica sol (with a particle size of 5-25 nm) is proposed, as well as a grounded choice of grinding parameters is made. Influence of protolytic properties of liquid phase on dispersion speed, aggregate and sedimentation stability of the silica sol are studied. The obtained dependence of the ...

The paper tries to make a study on the kinematics of the mechanisms involved in robot composition, the theoretical foundations of the dynamics of industrial robotic systems and the structure of a mechatronic micro-position system used in manipulation operations in order to optimize and correct the performances. The robot is a complex automated system that has the role of manipulating the parts and tools, replacing the action of human. An industrial robot is a system that does not operate in isolation, it communica...

The paper presents and analyzes the experimental results obtained by the welding reconditioning of a pressure vessel made of 14CrMoV4, a Romanian trade of steel, which is the equivalent of 13CrMo4-5, in the European norm 10028-2/2009, steel, which functioned for a long period of time in the energetic industry. The welding process used for reconditioning is robotized gas metal arc welding (GMAW). A series of samples were realized using different technological parameters in order to obtain different geometrical conf...

Innovative methods in the investigation of low-grade uranium ores were tested. As the individual ore components in the rock are optically undetectable, we focused on the detection of selected elements (U, Zr, Fe, Nb), their possible associations and distribution. For this purpose, mineral mapping of sample surface was used. The studied samples are uranium-bearing sandstones with remarkable elemental and mineral compositions. Low concentrations of the main ore elements and the small size of mineral phases (in micro...

Engineering novel material structures has continually been pursued to further advance modern technologies. These advancements often rely on novel processing technologies. Although many processing parameters have been thoroughly examined in the field of composition coatings, the formation processes are an exception. In this work, we examine the unique microstructures of composite electrolytic coatings, obtaining from electrolytes-suspension which contains nano-size particles of SiO2 and carbon. Metallographic resea...

Conductive polymer composites due to their unique properties and potential in various applications including chemical and bio sensors are receiving much research attention in recent times. The study investigate the effect of increasing polymer concentration and the influence of mixing time on morphology and electrical conductivity were. A highly conducting nanofiller and reduced graphene oxide (RGO) was incorporated into the matrix of expanded polystyrene; a recycled polymer, and the solution was electrospun under...

Nanostructured black silicon wafers were obtained in a two-stage process of selective chemical etching initiated by metal nanoclusters. The obtained silicon wafer surfaces demonstrate the reflectance of 2-3% in the visible range. Surface-enhanced Raman scattering (SERS) effect was observed on silicon substrates coated with silver or cooper nanoclusters. Test substance of Rhodamine can be detected up to concentration of ~10- 12 ? by using nanostructured silicon substrates covered with silver nanoparticles. Dependen...

Limestone deposits are primary raw material for cement manufacturing plants. However, mining engineers and geologists faces challenges in determining an appropriate, accurate and cost effective estimation method. The aim of this research is to evaluate and compare the applicability of two geostatistical methods, Ordinary Kriging (OrK) and Inverse Distance Weighting (IDW), for estimating quality of the Ta Thiet limestone, a lithological structure deposit at Binh Phuoc province (Vietnam). For this purpose, data coll...

Nanocomposites have been considered as a stimulating route for creating a new type of high performance material that combines the advantages of polymer and the nanoparticles. Polyamide is well known as an engineering thermoplastic material that is widely used in industrial applications for its good mechanical and thermal properties. The paper presents the study of the new nanostructured polymer composites from polyamide/oxidized graphite nanoparticles-PA/GO to manufacture, by injection, bearing seals, contact plat...

A learning algorithm was used as an artificial neural network (ANN) tool to predict the mechanical properties of some iron-based powder metallurgy (P/M) materials. Specimens prepared from atomized iron powder and from pre-alloyed iron base powders powders were analyzed in this paper. The specimens were fabricated by press and sintering of the mixed powders. The samples were compressed in a universal mechanical testing machine to a pressure of 400 and 600 MPa. The sintering temperature was approximately 1.150 пїЅC....

In this paper, the authors discussed one of the Hume-Rothery conditions for occurring substitutional solid solutions in the context of binary relations. The analyzed condition says that substitutional solid solutions may form if the ionic radius of the solute and solvent ions differ by no more than 15%. Because the problem concerns a mathematical connection between two objects, the authors suggested describing this problem using the set-theoretic notion of binary relation. In this context, the possibility of formi...

The current demand for energy production in dissipated systems and the related need for miniaturization of power machines require the use of appropriate technical solutions. Increasingly, power generation microsystems are used to produce electricity that functions in hermetic circuits (e.g. ORC - Organic Rankine Cycle). Rotors of such type of machinery, in order to generate the expected amount of energy, must rotate at speeds up to 100,000 rpm. Rotational speeds of this order represent significant problems in the ...

Aerogels production consists of two main stages: preparation of the gel filled with solvent (alcohols, acetone or hexane) by polymerization or sol-gel process and its supercritical drying. The most energy consuming and complicated from a technical point of view is the drying step [1]. Supercritical drying allows keeping the internal structure by preventing collapse of pores. Supercritical conditions require the use of expensive highpressure apparatus and the process rate is limited by diffusion within the pores of...

The development of materials science is in direct connection to the production of composite material with specific properties and to the technologies for their fabrication. The unique properties of the composites fabricated in Ti-Al-B-C systems makes them attractive for aerospace, power engineering, machine and chemical and other practical applications. Besides, Aluminum matrix composites (AMCs) have great potential as structural materials again due to their excellent physical, mechanical and tribological properti...

The magnetorheological (MR) fluids include ferromagnetic and paramagnetic particles suspensions with sizes included between 0.03 and 10 ?m, located in a carrier fluid (usually mineral oil). The complex fluid viscosity strong depends of magnetic field applied. Each particle can be considered a small magnet, which tends to align in the direction of the magnetic field. The magnetorheological fluids have the ability to change their viscosity when they are introduced into a magnetic field, due to the aligned particles ...

The loss of an organ or part of an organism generates, in addition to loss of function, social and psychological disorders. The modern bio-technologies try to diminish their effects on affected humans. The advancement of modern medicine that uses biomaterials to solve issues related to tissues and organs reconstruction has increased the human life expectancy, rapidly. The most important factors that limit the lifetime of implants are certain corrosion and wear products, which can have negative effects on the human...

The wheat is one of the most important crop in the world, the area cultivated exceeding 200mil ha. One provocation for researchers is represented by the question "In the conditions of continued growth of world population, how can to improve the wheat yield in the condition of maintain or decreasing the cultivated area". The answer can be offered by the seed treatment with cold plasma. This paper contains the results of research regarding the using of cold plasma for wheat seed treatment. The research was performed...

The objective of the study was to increase the solubility of amiodarone hydrochloride by complexation with hydroxypropyl-пїЅ-cyclodextrin. After complexation a cyclodextrin/amiodarone inclusion complex was formed. The use of media containing surfactants is a suitable solubilizing method and as a result, a non-ionic surfactant - Tween 80 and an anionic one - sodium lauryl sulfate have been used. The dissolution profile of amiodarone hydrochloride and that of the inclusion complex, regarding the release of the activ...

This paper focuses on the influence of the fiber glass functionalization agent on the properties of the polymer composites. Thermoplastic polymers are novelty materials, with special properties, depending on the type of elastomer, the degree and type of functionalization agent of the reinforcing material etc. Thus new impact and flame resistant advanced materials were developed and characterized. The polymers chosen for this study were polyamide (PA), a thermoplastic polymer that has high temperature resistance an...

Metal Oxide Varistors are today used for manufacturing state of the art overvoltage protection equipment, at any voltage level, being one of the most common power electronic devices existing on the market. They are widely used because they have a very high non-linear dependence between the applied voltage and the resulting current, and a relatively high energy absorption capability in case of normal overvoltage shocks or even in case of permanent overvoltages. Researches could be carried out both for finding a new...

Membrane processes used in wastewater treatment are categorized as the best techniques available at this time because it has advantages in terms of quality and costs. The membranes have different properties depending on the obtaining parameters. Their properties can be influenced throughout the membrane fabrication steps: when the polymer solution is prepared, when the polymer solution is applied in form of a thin film and also even after the thin film membrane is removed from the coagulation bath. Some important ...

The occurrence of nonconformities in prosthetics or medical instruments as a result of the manufacturing process or final machining (finishing) may lead to the decision of not using them in the medical process. The present paper aims to analyze the welding reconditioning possibilities in order to ensure the necessary geometrical characteristics, using the method of finite element analysis (FEA), of the interlocking intramedullary nail prosthetics made of titanium or titanium alloys. After identifying the nonconfor...

The results of experimental research of hydration process of highly dispersed systems based on saponit-containing waste, extracted as the solid phase of the recycled water suspension kimberlite ore enrichment process of the diamond industry. Saponitcontaining sludge was dehydrated and subjected to mechanical activation on the planetary ball mill. Mechanical activation of raw material more than 60 minutes does not increase the specific surface area of samples was found. Specific surface area is achieves the maximum...

The paper marks evaluation of existing me thodological tools for the formation of polymer composites, summarizes in brief the known technical designs and recent points of view for functioning of the old processi ng methods. Further, to make these systems usable in a practical working environment we will focus on the implementation of well- established utensils and ou tline possible new viewpoints for the modern revelations. Here, we will involve identified developments and routine utilizations, and will propose pr...

Mining and Metallurgy Institute in Bor, Se rbia, has successfully dealt for many years with processing of precious metals. Platinum and palladium have originated from the raw materials of the Bor deposit. By furt her refining in the Institute, the mentioned platinum metals are transformed into high-pu rity metals of which products for various purposes are manufactured. This paper presents the results of comparativ e analysis the high temperature strength of platinum and palladium. The limit of tensile strength as ...

Complex uranium ores of Kazakhstan are a potential raw source of gold and RRE, for example, scandium. Experime ntal researches on opening of ores various leaching systems are spent. It is shown, that uran ium accompanying metals can be extracted in solutions.

Tin selenide SnSe was synthesized from tin and selenium powder precursors by high- energy milling in pl anetary ball mill. X-ray diffractio n analysis confirmed that an orthorhombic tin selenide SnSe phase was formed already after 4 min of milling. 119Sn Mössbauer spectroscopy documented the values of SnSe isomer shifts corresponded to Sn in the oxidation state II. The size and morphology of tin selenide particles were studied by specific surface area measuremen ts, and transmission electron microscopy. Specific ...

The main aim of the work is theoretical and experimental research of nanocomposite systems formation process on the model of chromium electrolytic coatings, ascertainment of laws and mechanis ms of silicon dioxide nano-sized particles influence on the structure and properties of metal. We researched the process of electrolytic formation of chrome - silicon dioxide nanocomposite systems and nanostructured composite electrolytic coatings with silicon dioxide (3-50 nm) used as a dispersed phase. Methods of the resear...