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Erythromycin (E), a hydrophobic macrolide antibiotic, is prescribed for the treatment of acute bacterial infections, such as respiratory, urine, skin, and mouth infections. The main disadvantage of ER is its poor water solubility (2 mg/mL) that limits both formulation using hydrophilic bases and skin permeability. Cyclodextrins (CDs) are biocompatible cyclic oligomers of glucose, with a hydrophobic core and a hydrophilic exterior. CDs are used to improve the bioavailability of drugs by increasing their solubility ...

Mesoporous silica nanoparticles have recently attracted researchersпїЅ attention by opening a new perspective on the development of new drug delivery systems. Such mesoporous materials are characterized by a uniform distribution of pore size, welldefined walls with a high volume that enables functionalization at the level of silanol group, having a large specific surface and good hydrothermal stability. The objective of this study is the synthesis and characterization of MCM -48 and KIT-6 silicate matrices, biomat...

The paper considers the problems that arise in the process of seeding in the production of sapphire single crystals by the method of Kyropoulos. This stage is the most important in the entire technological process, but at the same time the least automated. An approach is proposed for visualization of this stage, using technical vision. It is based on the processing of images received from the ip-camera. To observe the dynamics of growth and the crystallization front at the stage of seeding, we reviewed different a...

Machinery from all industries is subject to aging processes. For economic and time reasons, damage cannot be repaired by replacing worn or damaged parts, but the product must be reconditioned. One of the most used reconditioning technologies in the industry is welding. Reconditioning technologies are credible, when samples are tested standardized. In most cases, welded structures have undergone various types of destructive tests: tension, compression, torsion and fatigue.[1] Since fatigue tests cannot be made duri...

The fruit represents the group of foods with vegetable origin, very precious from nutritional point of view, rich in carbohydrates, cellulose, minerals and organic acids, needed daily for the human body. A popular form often used for preserving fruit in cold periods, are fruit compotes which occupies an important place in our daily diet. Pineapples and mango fruit are consumed fresh, cooked, juiced and also can be preserved. The aim of the study was to evaluate some physicochemical characteristics (pH, total solub...

The possibility of manufacturing compact accelerometer based on prefabricated elements has been shown. Since most of the sensitive element designs at the lowest cost possible to produce at different ranges of sensitivity, so accelerometer design will be flexible in terms of wide range measuring of linear accelerations. Paper describes an original method of calibrating an autonomous unit of accelerometers. Without the use of precision rotary tables, centrifuges, and independent of the vibration reason, it is possib...

The properties of aluminum and its alloy make them to be the first choice as manufacturing materials for different equipments and accessories. The light weight, high strength and improved corrosion resistance recommend aluminum and its alloy to be used specially in transportation and construction industries. The native aluminum oxide film formed after exposure in air presents voids and cracks and the exposure aluminum parts to corrosive environments which lead to the degradation and reducing their lifetime. In ord...

Surface modified superparamagnetic iron oxide nanoparticles (SPIONs) are a kind of novel functional materials, which have been widely used in the various areas. The main requirements to magnetic nanoparticles for biomedical applications are the nontoxicity, biocompatibility and high-level accumulation in the target tissue or organ, chemical stability, simplicity and reproducibility of synthesis. The composition and characteristics of the SPION surface have a strong influence on their stability, distribution, and b...

The present research is a part of the obtaining innovative medicine domain and is concerned with conceiving and developing new anti depressive medicines, endowed with a high therapeutically degree, low secondary effects and impact on the quality of life, through a research partnership. The impact of Borderline personality disorder (BPD) diseases, especially depression, is continuously growing and as a treatment, are used anorganic products based on lithium, such as lithium carbonate, lithium citrate or lithium oro...

In the automotive industry, but also in other sectors, since the 80s one of the most used methods of reconditioning is welding. In this way, various technologies have been developed for each batch taking into consideration their characteristics and use. To observe and determine the correctness and economic impact of these technologies, the samples must be checked by different types of destructive and non-destructive standard tests.The most demanding destructive testing on samples is the fatigue test with alternati...

High performance environmentally friendly aqueous adhesive nanodispersions for shoe manufacture were obtained by improving the polychloroprene adherence by chemical grafting of polychloroprene latex DISPERCOLL C 84 with methyl methacrylate in the presence of benzoyl peroxide as initiator. Grafting is demonstrated by the absence of monomer and polmethylmethacrylate in dispersions, decreasing of intensity of some bands assigned to polychloroprene as well as broadening and splitting of its C-C stretching band due to ...

Worldwide there is a need to develop new advanced materials based on silicone elastomers with high-performance properties, reinforced with nanoparticles. The curing process as a primary step has a major impact on the properties of the final product, including the determination of the optimal amount of reinforcing agent in the nanometer range and cross-linking agent (peroxides - specific to food, pharmaceutical, medical and consumer goods industries). The aim of the study is to obtain an antibacterial elastomer com...

The paper presents an automatic sorting process of different color pieces. This paper is the result of a multidisciplinary depth study focused on industrial automation field more specifically on robotics, informatics, or control of the flexible manufacturing systems. The hardware and software system is formed by a robotic arm, a color sensor, sensors, a conveyor, a system of outlet cubes and a storage system, a transporting system for the robotic arm. The goal of this paper is to remove cubes from the deposit use ...

In past decades design of experiments and simulation analysis have been recognised as powerful tools for resource efficiency improvement in various areas of technics and technology, especially for energy-consuming industries such as ceramics production. Silicon carbide ceramics is widely used for structural applications, yet production of such materials invokes high temperatures and sintering aids, thus it becomes an important task to carefully adjust ceramics compositions and methods of manufacturing. Promising s...

During the last decades, problems related to environmental pollution have become even more acute. Therefore there is a need for new sources of a clean energy. Steam reforming of alcohols, which are much morechemically active, proceeds at considerable lower temperatures. It is important also that alcohols produced from biomass (bio alcohols) can be considered as a renewable raw material. The aim of this work were the development of catalysts based on the complex oxides (ZrO2 - Al2O3 - CeO2) support and the study of...

The goal of the present study is to evaluate the use of mesoporous silicate nanoparticles MCM-41 for the loading and release of the magnolol. MCM-41 has a hexagonal arrangement of mesopores, with diameters ranging from 2 to 10 nm. The homogeneity of the cylindrical pores, high surface area with uniform porosity, and good thermal stability, which make them an attractive molecular sieve for applications in sorption of large organic molecules, as well as host for quantum confinement of guest molecules. Also, the bioc...

The purpose of this paper was to study the effect of carbon content on the dimensional characteristics of some powder metallurgy (PM) materials. The powders used in this study are atomized pure iron and prealloyed iron-based powders with Cu, Ni and Mo. Some elements as copper, nickel, molybdenum, manganese and phosphorus are the most common alloying element added in powders form because of its low cost, availability and capability to improve the properties of alloys. The particle size of the analyzed powders is ra...

The objective of the study was to evaluate the effect of processing parameters such as pressing and sintering time on microstructural characteristics including porosity and microstructure of some iron-based powder metallurgy (PM) materials. The powders used in this study are prealloyed iron-based powders. The particle size of the powders is ranging from 45 to 150 ?m. Following mixing the powders with zinc stearate 1% for 30 minutes, the studied powders were single pressed in a die at a pressure of 600 MPa. Zn-stea...

Based on a previous research, a thermal bimorph actuator was used for a development of a micromirror element. An existing technological process for the manufacturing of IC was used as base for micromirror. An analysis of the available construction materials was made, on the basis of which a choice was made for silicon as the main material for the micromirror, aluminum as the reflective coating and the first element of the bimorph beam, and silicon dioxide as the second element of the bimorph beam. ? polysilicon he...

Total (specular+diffusive) reflection of nanostructured Si layers prepared by metal assisted chemical etching (MACE) of crystalline silicon (c-Si) wafers is investigated. The thickness of nanostructured Si layers is varied from 0.3 to 100 ?m by increasing the MACE time. The time dependence of silicon nanostructured layers thickness on the etching time was found to be logarithmic. Spectra of the total reflection were measured in optical range from 0.2 to 2 ?m. Depending on the thickness of sample, it was observed a...

Anthocyanins are known as safe colouring materials, although they have poor stability which often limits their use. To solve this drawback, mesoporous silica with high surface area was used as an adsorbent for anthocyanins. This study proposes the enhancement of the anthocyanins photo stability by their incorporation into the pores of mesoporous silica containing various metal ions. The anthocyanins were adsorbed on the silica by pouring a highly-concentrated anthocyanins solution to the dried silica. Improved sta...

Polyoxometalates (POMs) are discrete, anionic metal-oxygen clusters of early d bloc metal ions in high oxidation status (e.g. MoVI, WVI) with a very large structural and compositional variety, leading to interest in many different areas (catalysts in homogeneous and heterogeneous catalytic oxidation of organic compounds or biochemical reactions, activity in enzymatic redox processes, as antitumoral, antibacterial and antiviral treatments etc). An important subclass of POMs is the {XMo6O24} structure type, Anderson...

Phosphate removal from wastewater is necessary at sewage treatment plant before discharging into the natural streams due to many reasons especially to preserve phosphate and to avoid eutrophication. Magnetite nanoparticles stabilized on ZSM-5 zeolites were used to adsorb, remove and recover phosphate from said wastewater. Three samples namely, magnetite, magnetite@ZSM5 and ZSM-5 were used for batch adsorption experiments. Results indicated the highest phosphate removal efficiency for magnetite@ZSM-5 material. Magn...

Wear-resistant composite coatings reinforced with Al2O3 nanoparticles (20nm) obtained by electroless technique are analysed in this paper. The structure and surface morphology of coatings with alumina nanoparticles embedded in the Ni-P alloy for different quantities of alumina in the nickel-plating bath (3g/L, 5g/L and 8g/L) are presented. Nanocomposite electroless coatings are characterized by optical microscopy, XRD and SEM. Microstructure of the composites has revealed uniform distribution of Al2O3 nanoparticle...

1050 aluminum alloys are used in the conventional engineering applications where the increased corrosion resistance is required (e.g. automotive industries or construction, containers). Improving the corrosion resistance of 1050 aluminum alloy is an extensively studied topic. Different methods are applied to improve the corrosion resistance of 1050 aluminum alloy as: painting, waxing, zinc-chromate priming, thin layer of pure aluminum, coatings with a liquid protective solution, conversion coatings and also anodic...

In this article, the authors have analysed the influence of ultrasound, used in the quenching from the intercritical range (? + ?), on the volume fraction of martensite in the microstructure of a dual-phase steel with 0.087% C and 0.511% Mn. The ultrasonic oscillations, applied to the medium in which the quenching takes place, under the action of pressure and cavitation phenomenon, destroys and prevents the formation of vapor and gas films, thereby ensuring a more prolonged contact between the workpiece and the co...

In this work, the organic silicon-based composites were obtained from resorcinol, formaldehyde, TEOS, N-(b-aminoethyl)-g-aminopropyl-trimethoxysilane (AEAPTES) as initial materials for carbon-silica composites producing. The solvent was acetone, those molar ratio to resorcinol varied in following: sample S1 ? 1:11; sample S2 ? 1:14 and sample S3 ? 1:19. Gels were prepared by one-stage method. The silica-organic gels were supper-critical dried. It was shown that the heat treatment of silica-organic gels allows gett...

It is well known that the use of aluminium and its alloys in transports, aeronautics or in the car industry as a vehicle downweighting material, also decreases fuel and energy consumption and lowers greenhouse gas emissions. In our study, an innovative thermomechanical processing technology for obtaining flat ultra-strength aluminium products by subsequent cold rolling after equal channel angular pressing (ECAP) was proposed and experimented. ECAP is an advanced severe plastic deformation (SPD) method for controll...

Recent surge in the number of studies on inorganic nanoparticles has raised concerns over possible commercial implication of the same. The developmental stage of regulations and standards controlling the same amplifies this problem. In this perspective, we tried to analyze the current trends on lignocellulose nanomaterials (viz. Nanocellulose and lignin) and its global potential to offer an environmentally benign alternate. We used number of studies indexed in Scopus database to get an idea of trends. An additiona...

The aim of the present work is to develop, substantiate, and study a fundamentally new method of derivation of composite electrolytic films making it possible to control their composition and structure. We assume that, after the termination of the stirring-up of a bath containing the electrolyte-suspension with monodisperse spherical particles of the same density, a uniform sedimentation space is established. The upper boundary of this field will descend with a velocity depending on the dispersity and density of a...

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...

The importance of wastewater treatment is growing rapidly with the populationпїЅs need of access to pure water and industrial process water. Different wastewater treatment technologies are available worldwide but the membrane treatment technology has earned popularity in the last decades because of cost/efficiency reasons. Polymeric membranes lead the market in membrane manufacture because they are very competitive in performance and economics. Polysulfone is one of the most used membrane material and has advantag...

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...

The results of microstructure study, X-ray microanalysis, microhardness, porosity of sintered samples from a powder high-speed steel before and after hardening by the wave intensive plastic deformation are presented. It has been established that the basic elements in the composition of sintered samples from tungsten powders are C, O, Mo, Ca, V, Cr, Fe, W. Based on the analysis of the sintered samples microstructure, it was determined that the there is a uniform distribution of solid carbide in the base material vo...

The processes of nanogold deposition and concentration in the environment, which have been occurring with enlargement of metal grain size, may be considered as the natural nanotechnologies. The mechanisms of nanogold concentrations in geological objects are established and described on the example of many deposits in Russia (the Urals, Siberia) and abroad (Canada). They produce different morphological and chemical aggregations of gold nanoparticles. Among them variable growths on the placer metal surface, globular...

Nanoparticles of magnetic fluids are stabilized with various surfactants. Lignosulfonates are water-soluble byproducts of sulfite pulping process. The aim of our work is to estimate possibility of using nitrated lignosulfonates for stabilization of water-based magnetic fluid and determine optimal nitration conditions. Nitrolignosulfonates were synthesized by nitration of sodium lignosulfonates with nitric acid and the products without further purification were used for preparation of magnetic fluid. Magnetic nanop...

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 the present work, polymer-silica hybrid latexes based on methyl methacrylate (MMA), butyl acrylate (BuA), 2-hydroxyethyl methacrylate (HEMA), and different inorganic precursors (tetraethoxysilane (TEOS), isobutyltriethoxysilane (IBTES), diethoxydimethylsilane (DEDMS), vinyltriethoxysilane (VTES)) were synthesized by emulsion polymerization and sol-gel process. The resulting latexes were characterized both as materials placed into plastic vials and as films deposited onto clean glass slides by various techniques...

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...

Iodine adducts are increasingly being used as the drugs and materials with antimicrobial properties. Using them as biocidal reactive materials in the highly crowded premises, hospitals and maternity homes, can stop the development of epidemics caused by microbes that are resistant to common antibiotics. The iodine adducts formed in the lysine-iodine-potassium iodide system served as the object of the present study. The purpose of the work was to obtain data on structural-phase transformations in the genesis of iod...

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 ...