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Coordination compounds of metals and their halides with biologically active organic ligands can be used to produce materials with various optoelectrical and magnetic properties. Some of them can enhance the tunnel effect. Complexes of metal halides with amino acids and halogens with various structures have been synthesized. Lithium halides, which form complexes with electron-donor molecules are of particular interested for biological applications. The studies on coordination compounds of lithium halides with amino...

This paper reports the synthesis of hybrid zirconium sol-gel coatings by solпїЅgel process at room temperature (25 пїЅC), using tetraethoxysilane (TEOS) as a precursor and different alkyltriethoxysilanes (RTES) with variable organic functionality (methyl, vinyl and octyl) as surface modifying agents. All silica materials was prepared with zirconium(IV) propoxide (as cross-linking agent), by keeping the molar ratio of TEOS:RTES at 1:1, in acidic conditions. The zirconium sol-gel films were obtained by depositing th...

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...

New materials based iron powder, with several addition elements obtained by powder metallurgy. The sample were obtained by compacting of 500 M Pa , obtaining a sampless and sintering in dry hydrogen atmosphere at the different temperatures. The sintered samples were metallographic prepared by polishing in order to investigate the porosity and evaluate the microhardness of individual grain and structural constituents. I am studing the effect of addition elements on Rockwell hardness and microhardness. Hardness is t...

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 ...

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...

This article presents results of the studies conducted by authors for determining the influence of ultrasounds, used in the intercritical quenching, on the structure of some low carbon and manganese dual-phase steels (0.087% C and 0.511% Mn, respectively 0.101% C and 0.529% Mn). The samples of these steels were heated to temperatures between 760 and 820 ?C (temperatures between the critical points Ac1 and Ac3), for 30 minutes and then quenched in water, water in ultrasonic field with frequency of 40 kHz and water ...

Comparison of microcrystallites morphological structure of microcrystalline cellulose specimens obtained hydrolytically from plant and bacterial cellulose microfibrils is described. Micromorphological characteristics of the structures are visualized using SEM Sigma VP ZEISS scanning electron microscopy. The crystallinity degree of the microcrystalline cellulose specimens is calculated by new method using X-ray diffractometry (XRD-7000S diffractometer). Native bacterial cellulose is obtained on the glucose media us...

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...

Corrosion is the deterioration of a metal as a result of chemical reactions between it and the surrounding environment. Is a natural process, which converts a refined metal to a more chemically-stable form, such as its oxide, hydroxide, or sulfide. It is the gradual destruction of materials (usually metals) by chemical and/or electrochemical reaction with their environment. Biomaterials are used to replace a part of the body functions lost due to illness or to improve functions and to correct anomalies. The import...

In this paper, thin films TiCx was coated by chemical vapour deposition method, and various duty cycles were carried out in order to observe the influence of this parameter on residual stress and tribology behaviours. The duty cycles were 35, 43 and 50% at 500uC operating temperature. Therefore, wear behaviour, hardness and chemical analyses of TiCx coating were characterised, and it was found that the residual stresses in the coating were compressive, which were- 1.4189, - 0.2985 and -0.1749 MPa at three differen...

Cyclophosphamide - N,N - bis (2 - chloroethyl) - 1,3,2 пїЅ oxazaphosphinan пїЅ 2 -amine 2-oxide is one of the widely used drugs in cancer treatment, which presents genotoxic, carcinogenic, mutagenic and teratogenic potential. Previously reported studies proved that long time exposure to cyclophosphamide and their metabolites leads to negative effects upon the environment and human health. Therefore, there is a need for more performant treatment processes for cyclophosphamide advanced degradation from which heterog...

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...