Study Of Mechanical Properties Of Aluminium Lm25 Using Stir Casting Method

The present study deals with the behaviour of aluminium hybrid alloy based composites, reinforced with fly ashnbsp particles and solid lubricants such as activated carbon .The first one of the composites consists of Al. with fly ash particlesnbsp and activated carbon. The other composite has Al with fly ash and solid lubricant: activated carbon at solid state. Both composites are fabricated through lsquoStir Casting Methodrsquo. Mechanical properties of the samples are measured by usual methods such as Hardness,Tensile .The tested samples are examined using Scanning Electron microscope (SEM) for the characterization of microstructure on the surface of composites. The Main Aim is to be results of the proposed Hybrid composites are compared with Al based metal matrix composites at corresponding values of test parameters

Nanoparticles for hyperthermia applications

Cancer is one of the leading causes of death worldwide, and unfortunately many cancer treatments have severe side effects. In order to avoid these, recent investigations into new oncological treatments have been carried out. In this context, composite biomaterials have been developed mainly from biopolymers or magnetic hydroxyapatite nanoparticles with the aim of directing and releasing drugs by means of an external magnetic field (hyperthermia). This chapter reviews recent advances in nanoparticle (NP) systems for hyperthermia applications with particular emphasis on the heating mechanisms of iron NPs (INPs) and their applications as composite biomaterials.Fil: Gutiérrez Carmona, Tomy José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Alvarez, Vera Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentin

Understanding the water absorption from MHEC modified glue mortar into porous tile: influence of pre-drying

This article presents an experimental investigation on the influence of Methylhydroxyethylcellulose (MHEC) modified mortar on water absorption into tile and base substrate using Nuclear Magnetic Resonance (NMR) imaging. Addition of MHEC shifts the absorption behavior from homogeneous to inhomogeneous as a result of increased viscosity of pore solution. The observed reverse flow from tile to mortar is a result of decrease in capillary pressure in mortar as a consequence of decrease in pore size due to hydration. Pre-drying of 1.3 wt% MHEC mortar with dry air shows little wetting by tile due to MHEC transport and formation of dry region at the mortar surface. On the contrary, pre-drying of 1.3 wt% MHEC mortar at 40% RH slows down MHEC transport and delays the formation of dry region at the mortar surface enabling higher wetting by tile

Transport of a water-soluble polymer during drying of a model porous media

This article presents an experimental investigation on transport of methylhydroxyethylcellulose (MHEC) during drying of a model porous material. Nuclear magnetic resonance imaging and thermogravimetric analysis are used to measure water and MHEC transport, respectively. MHEC is added to glue mortars to increase open time, i.e., the time period during which tiles can be applied with sufficiently good adhesion. Previous work showed that MHEC promotes a receding front during drying and therefore leads to differences in the degree of hydration throughout the mortar sample, i.e., the top surface shows poor hydration and the bottom surface shows good hydration. In this study, we investigate the transport of MHEC during drying of a model porous material, consisting of packed glass beads saturated with an aqueous MHEC solution. At MHEC concentration less than 1.3 wt%, homogeneous drying is observed, enabling advective transport of MHEC toward the drying surface. In this case, accumulation of MHEC may form a skin at the top surface and below this skin layer, a gel zone may form, which allows migration of water toward the evaporation surface. When the MHEC concentration is above 1.3 wt%, front receding drying is observed, which prevents transport of MHEC, resulting in a more homogeneous distribution of MHEC

Effect of MHEC on evaporation and hydration characteristics of glue mortar

The influence of methylhydroxyethylcellulose (MHEC) on both moisture distribution and hydration characteristics of glue mortar using nuclear magnetic resonance imaging (NMR) is investigated. MHEC is added to glue mortar in order to control the drying rate by increasing the open time. Besides drying, MHEC might influence hydration characteristics of mortar. In this study, we therefore examined the effect of MHEC on the hydration characteristics of unsealed mortar. Without MHEC, the evaporation time is faster than hydration time and the water distribution is homogeneous in the mortar, resulting in poor hydration. Addition of MHEC > 1.3 wt.% exhibits an evaporation time comparable to the hydration time of mortar. However, in that case, inhomogeneous distribution of water causes differences in the degree of hydration throughout the mortar sample, i.e. the top surface shows poor hydration and the bottom surface shows good hydration, as confirmed by MIP and T2 relaxation analysis

Dependence of pH and surfactant effect in the synthesis of magnetite(Fe3O4) nanoparticles and its properties

Nanoparticles of Fe3O4 were synthesized by co-precipitation in an aqueous solution containing ferrous and ferric salts (1:2) at varying pH with ammonia as a base. It was found that the value of pH influences the reaction mechanism for the formation of Fe3O4. Furthermore, the addition of mercaptoethanol significantly reduced the crystalline size of Fe3O4 nanoparticles from 15.03 to 8.02 nm. X-ray diffraction (XRD) spectra revealed that the synthesized nanoparticles were epsilon-Fe2O3 or Fe3O4 phase. To further prove the composition of the product, as-prepared Fe3O4 were examined by X-rayphotoelectron spectroscopy (XPS). Magnetic properties of the obtained particles were determined by vibrating sample magnetometer (VSM). Further analysis of the X-ray studies shows that while maintaining a pH value of 6 and 9 in a solution containing iron salts II and III ions produces epsilon-Fe2O3. Whereas a pH value of 11 produces magnetite (Fe3O4) phase. All of these results show that the pH has a major role in the observed phase formation of (Fe3O4) nanoparticles

How methylhydroxyethylcellulose (MHEC) influences drying in porous media

This article presents both an experimental as well as a theoretical study on the effect of MethylHy droxyEthylCellulose (MHEC) on drying in porous materials using Nuclear Magnetic Resonance Imaging (NMR). MHEC, a water soluble polymer, is normally added to glue mortars as a water retention agent in order to improve the drying by increasing Accepted the open time. However, the exact processes that determine the drying rate of a glue mortar are unknown. In this study, we therefore focus on investigating the drying of a Fired day Brick (FCB) saturated with an aqueous MHEC solution. By using a FCB as a model system, the influence of hydration and changing of pore sizes due to hydration can be removed. The performed NMR experiments show a transition from homogeneous drying for a water saturated FCB toward an inhomogeneous (front receding) drying behavior for FCB saturated with increasing MHEC concentration. The capillary number (Ca) indicates a homogeneous drying for water saturated brick (Ca«i) and an inhomogeneous drying (Ca»1) in case of saturated brick with more than 1.5 wt% MHEC. Analysis of capillary number shows that the main parameter determining the capillary numbers are viscosity, surface tension, contact angle and evaporation rate. Among this viscosity change match with change in capillary number and therefore viscosity has a major influence on the drying behavior and rate. Based on the measured profiles, the moisture diffusivity is calculated. Using an empirical equation, the moisture diffusivity and NMR profiles were fitted to obtain the key parameters. From these analyses we conclude that 1) the moismre diffusivity scales with viscosity, which is the main parameter in shift in drying behavior. 2) Surprisingly, the presence of MHEC reduced the evaporation, which is unexpected since evaporation of MHEC solutions, for instance present in capillaries do not exhibit this behavior. 3) A minimum moisture diffusivity is found which shows to correlate to the evaporation process, which indicates that this might be the result of a vapor dominated diffusion flux

Effect of MHEC on evaporation and hydration characteristics of glue mortar

The influence ofmethylhydroxyethylcellulose (MHEC) on bothmoisture distribution and hydration characteristic