Articles Related to Materials

In literature are reported various use of activated charcoal AC and derivates in biopharmaceutical purifications.Aim of this work is to verify impurity proficle when using this technology.Various commercial products are reported here but it is not the scope of this work put in relation with any toxicological reaction: only to describe the technique used in this field.Because various drugs and bioproduct need purification steps it is if of interest to see some material science peculiarity

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Increasing the nickel content in the layered LiNixCoyMnzO2 (x + y + z = 1), the most promising cathode materials for lithium ion batteries (LIBs), has been a dominant strategy to increase their energy density. In this study, we report the control on the primary particle morphology of precursors with different nickel contents, e.g. Ni0.5Co0.2Mn0.3(OH)2 Ni0.6Co0.2Mn0.2(OH)2 and Ni0.8Co0.1Mn0.1(OH)2 by adjusting the preparation process. The scanning electron microscopy (SEM) images demonstrate that by decreasing the pH value and increasing the ammonia concentration, the order of precursors with different nickel contents increases, resulting in gradually directional and orderly stack or interlaced arrangement in the primary particles. With the increase of nickel content, the precursor changes from nano-sheet stacking like plug-in stereoscopic spheres to nano-needle interweaving like wool balls, all of which tend to grow in the direction of [001].

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Dental practice involves a risk of exposure to microorganisms causing many infectious diseases. The risk of contamination starts at the beginning of the prosthetic workflow through impressions. Various chemical disinfection protocols for dental impressions are reported in the literature.

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Introduction: The prosthetic act must obey the rules of asepsis with a certain rigour for the decontamination of impressions to reduce the risk of cross-contamination. The objective of this study was to evaluate the knowledge and attitudes of practitioners in the Dakar region (Senegal) regarding the decontamination of impressions. Materials and Methods: This was a cross-sectional descriptive epidemiological survey of 150 dentists in the Dakar region. Results: The sample consisted of 59,3% men and 40,7% women. Practitioners practising in private practice were 61,0% against 39% in public practice. The majority (83.3%) of dentists in the study had not received any continuing education on aseptic procedures in prosthetics and had a vague idea of the term "decontamination of impressions". Nevertheless, almost all practitioners (94,0%) systematically rinsed the impressions with water after disinsertion, 48.7% of practitioners decontaminated their impressions with a disinfectant. The most used decontamination methods were immersion at 70.3% followed by spraying at 17.1%. Sodium hypochlorite (63.9%) was the most used solution due to its effectiveness, simplicity of use and cost. Conclusion: There is diversity in the attitude and knowledge of dentists. Disinfection protocols that are simple to implement and adapted to the impression materials should be put in place. Moreover, a rinsing as soon as the mouth is removed must be carried out, then a post-disinfection rinsing for a better dimensional stability of our impressions.

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A new method for repacking optical metamaterials formed from fiber or spherical elements of various diameters is proposed for ultraviolet C (UVC) decontamination of infected liquids that flow between these elements. It is proposed the method of repacking of metamaterial formed from closed packing big fibers/spheres with other subsystems of thin fibers/ bubbles replaced in the free space between the first packing fibers/spheres.

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The encapsulation method is a process applied to increase the shelf life of the active food components, ensure their stability, perform their controlled release and improve their functional properties. Active particles such as fatty acids, peptides, vitamins and probiotics are coated with coating materials such as starch derivatives, gelatin, gum arabic to eliminate external effects.

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Tooth decay is a progressive disease caused by acid fermentation of carbohydrates by pathogenic microorganisms in the mouth, leading to demineralization of teeth.

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In this paper we analyzed changing of dynamics of redistribution of dopant during manufacturing of diffusion-junction rectifier in a heterostructure due to radiation processing.

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A kind of alcohol-soluble phosphate adhesive was prepared by using phosphate solution as raw material. A hybrid high temperature and high strength adhesive was prepared by adding phenolic resin. The wetting condition of water-soluble and alcohol-soluble phosphate adhesive on the surface of hydrophobic material, the composition and mechanical properties of the adhesive were analyzed by means of liquid drop shape analyzer (DSA), X-ray diffraction instrument and universal tensile force machine. The results show that the alcohol-soluble phosphate adhesive has good wetting effect on hydrophobic materials and has excellent high temperature resistance and mechanical properties.

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Pollution, being a social and environmental problem, has been a subject of inquiry by environmental economists. Environmental economists see pollution as an externality problem or a market failure, and have therefore investigated factors affecting pollution and its control.

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The term biomaterial is used for materials used in medical implants, extracorporeal and disposable devices, and must have compatible biological, physical, chemical and mechanical characteristics for use in humans. Objective: to identify and characterize the biomaterials used for the preparation of orthopedic orthoses.

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Security agencies are always saddled with huge responsibilities of trying to establish evidences to link a suspect to a particular crime. But in most cases, there are always very limited physical evidences due to the complexity of the crime. However, forensic palynology provides a very good option, because pollen and spores from plants are very minute, ubiquitous in distribution and are seldom useful in recovery of vegetation of a certain locality. This present study aims to assess the feasibility of pollen, spores, and sand grains as associative evidences recovered from a suspect linked with a crime scene. Forensic materials including soil samples from foot wear, dirt from clothes, earlobes and nostrils were retrieved from the body of a suspect at a particular location in Nigeria. The retrieved materials were subjected to standard laboratory palynological, biochemical and lithological procedures. The dionex analysis (anion) and atomic absorption spectrometry (cation) shows great similarity in the results obtained with an exception to Zinc. A considerable similarity was observed in the potential of hydrogen and salinity values of soil samples from both the suspect and crime scene. The lithological data reveals a great correlation in the colour, grain size, grain sorting, and grain texture and grain shape of these two different soil samples. The palynological analysis yielded a recovery of palynomorphs including pollen of Elaeis guineensis, Alchornea cordifoliia, Cassia fistula, Syzygium guineense, Cyperus papyrus, Pteris species and Nephrolepis biserrata were also recovered. This reveals the potential of retrieved materials from the body of a suspect as good sources of pollen and spores. It is however important to corroborate the use of palynomorphs and sand grains with other lines of evidences in solving crime-related disputes.

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The increase in the population of the planet and the rapid economic growth and, consequently, the high consumption of energy has created many environmental problems. Due to these reasons and the lack of renewability of these fossil fuels, there has been a steep trend towards the production of renewable fuels, one of which is the production of energy from biomass. In this study, biofuel production from biomass has been investigated using the pyrolysis method, a method that reduces the production of oil from millions of years to a few seconds, and is the most industrialized thermochemical method for producing fuel from biomass. This research focuses on thermochemical processes, pyrolysis principles, specifications, chemical composition and applications of biofuels, and the devices and equipment needed for it. This research is the A new approach for research and study on bio-refineries in the future.

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Vital pulp preservation in the treatment of deep caries is challenging due to sealing issue. The aim of this study was to compare the physicochemical properties and radiopacity of various light curing pulp capping materials. In this study, SEM-EDS analysis and the radiopacity of four different pulp capping materials including ThereCal LC, Biner LC, Calci Plus LC, and Activa-Bioactive were evaluated. Each material was characterized by scanning electron microscopy (SEM) and chemical composition of each material was analyzed by energy dispersive x-ray spectroscopic (EDS) analysis. The diskshaped specimens (8 mm diameter and 1 mm thickness) were prepared from each material and exposed to a digital x-ray along with an aluminum step wedge for the radiopacity assay. The statistical analysis was performed with ANOVA and Duncan’s post-hoc test.

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The results are presented of obtaining anodic aluminum oxide with an ordered pore arrangement by employing two anodizing modes - galvanostatic mode and combined (galvanostatic + potentiostatic) mode, at high values of the current density and voltage. Use has been made of an oxalate electrolyte and a complex electrolyte comprising oxalic acid and phosphoric acid. Scanning electron microscopy has been used to investigate the surface morphology of the barrier and porous layers and to determine pore sizes and inter-pore distance.

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Self-organized anodic porous alumina films with hexagonal pore lattice have attracted a considerable attention for biological arrays and confinement of various organic probes dyes in solutions. A molecular structure with axial symmetry in bis-heterocyclic indole chains and conjugate system, such as cyanine fluorophore Cy3 dye, was investigated here with respect to its fluorescence when loaded in the anodic alumina pores.

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Two basic reactions occur during the anodizing of aluminum: 1) the aluminum is consumed and 2) an oxide grows. By accepting this statement as true, the anodizing process can be viewed as a corrosion process, and anodizing can be modeled using the Tafel Equation. Anodizing process parameters of electrolyte chemistry and concentration, temperature, aluminum substrate resistance and current density are presented as they relate to the Tafel Equation and how they impact the anodic aluminum oxide structure and properties. Understanding this relationship is consequent in making anodizing an engineering process, one that enables tuning the structure such that it yields distinct characteristics to fulfill design and application requirements.

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The anodization of aluminum foils having micrometer thickness is a common process and results in hexagonally self-ordered alumina membranes. However, anodic aluminum oxide (AAO) membranes fabricated from nanometer-thin films present new challenges to the anodization process, since aluminum films adheres poorly on supporting substrates and the smoothness of the film is highly related to the kind of substrate.

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Anodisation of pure titanium has been carried out in sulphuric and in phosphoric acid solutions at potentials ranging from 50 to 150V. The SEM and AFM morphological analysis indicates that, within this potential range, oxidation in sulphuric acid solution produces better developed mesoporous oxide layers.

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We investigated a method for preparation of ordered nanopore arrays with the interpore distance of 60 nm by guided self-organization of anodic aluminum oxide with a prepatterned array of pits in the starting Al film.

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The design of an electrochemical reactor for the preparation of self-supported comparatively thin (up to 10 μm) and large area (up to 50 cm2) anodic alumina membranes is described allowing growth of porous alumina at high applied potential (up to 150 V) without burning.

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Vertical Cu2ZnSnS4 (CZTS) nanowire arrays have been synthesized via two-step electroplating method into anodized aluminum oxide template. For deposition of CZTS nanowires, anodized aluminum oxide (AAO) was used as the growth mask for the growth of the nanowires. AAO templates with hole sizes of 70 nm in diameter were used in the experiments.

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Anodic aluminum oxide doped with vanadyl citrate chelate complex anions was formed by a two-step self-organized anodization in 2 wt. % sulfuric acid containing 0.04 M V2O5 and 0.08 M citric acid at voltage range 13-23 V, and at 0 and 15 oC. The combination of two temperatures and at least four voltages (depending on the applied temperature) was applied as the operating conditions of anodization.

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In this paper, we report on the synthesis of BaTiO3 nanowires via the anodic aluminum oxide template method. To fill in the precursors of BaTiO3 into anodic aluminum oxide templates, the vacuum and drop loading method developed in our previous study was used. Ba(CH3COO)2 (barium acetate) and C12H28O4Ti (tetraisopropyl orthotitanate) were used as Ba and Ti sources, respectively. Anodic aluminum oxide membranes with the through-hole diameter of ~200 nm were used as the template for BaTiO3 nanowires.

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