Microwave-assisted preparation of multi principal element alloys by powder metallurgy approach

According to literature, the synthetic route to produce High entropy alloys (HEAs) should guarantee short alloying time, efficient cooling and capability to operate in controlled atmosphere. Such conditions can be achieved using high frequency electromagnetic fields, like microwave heating. In this work FeCoNiCrAl and FeCoNiCuAl, both equiatomic and reinforced by the 10% wt. of SiC were prepared by microwave assisted techniques. Results show that direct microwave heating of the powder precursors occurs, until the ignition conditions are reached. The temperature and duration of the microwave-assisted process result much lower than other conventional powder metallurgy routes, but at the cost of a higher residual porosity. Sample characterization confirmed that the powder metallurgy approach is suitable to retain the shape of the load imparted during forming by uniaxial pressing. The homogeneity of the samples resulted in being good in all cases, without the dendritic segregation typically occurring by liquid phase processing. © 2017 European Powder Metallurgy Association (EPMA

Vapor-Liquid Equilibria of Binary Systems: A Computer Simulation by LabVIEW

We report the results of the development and realization of a program using LabVIEW software to simulate the technique utilized in the laboratory to construct a phase diagram that represents a liquid–vapor equilibrium. The program has been set up so that the student can work as if in a real laboratory, including mistakes usually made in this kind of measurement

The conductivity of Strong Electrolytes: A Computer Simulation in LabVIEW

In this article, we report the results of the development and the realization of the program CONDSIM using the National Instrument’s LabVIEW software. The LabVIEW software permits the students to simulate the technique utilized in the laboratory to measure the strong electrolyte conductivity as a function of concentration and temperature. The program has been set up so that the student can work as if in a real laboratory, including mistakes usually made in this kind of measurement. The program CONDSIM.EXE and a PDF version of the instructor’s manual, CONDSIMINSTR.PDF, describing the simulation experience are available as supporting material

Characterization and quantitation of short chain fructooligosaccharides and inulooligosaccharides in fermented milks by high-performance anion-exchange chromatography with pulsed amperometric detection

With the increased interest in the possible link between fructooligosaccharides (FOS) intake from functional foods and health, the need for reliable data on the individual FOS content of those foods has become very important. In this study a new high-performance anion-exchange chromatography coupled to pulsed amperometric detection (HPAEC-PAD) method is described for the selective determination of short-chain FOS and inulooligosaccharides (IOS) present in the investigated prebiotic food ingredients. Response factor of PAD was investigated in relationship with degree of polymerization and isomers. The developed HPAEC-PAD method has been applied to characterize short-chain oligosaccharides of the inulin series with DP ranging from DP3 to DP7 and IOS from DP2 to DP7. Their quantification in commercial water-soluble fibers of relevant importance as prebiotic food ingredient added in fermented milks has been performed. in order to evaluate the reliability of the proposed method, results have been compared with those obtained by the official enzymatic method. Furthermore, this new HPAEC-PAD method may contribute to clarify the real importance, prebiotic effectiveness and biological role of these carbohydrates

Osteosintesi delle fratture laterali del collo del femore con chiodo non alesato PNF-A

Il controllo dei primi 20 pazienti affetti da frattura laterale del collo femorale, trattati con il chiodo no alesato PNF-A, ha permesso di dimostrare come tale nuovo mezzo di sintesi sia valido, tanto per la stabilit\ue0 del sitema stesso,quanto nel permettere tempi di esecuzione dell'intervento assai contenut

Validated HPAEC-PAD method for prebiotics determination in synbiotic fermented milks during shelf-life

Interest concerning functional food has been growing in recent years, and much attention has been focused on the choice of prebiotic fibers and probiotic microorganisms added to food products with the aim of improving health, producing synbiotic products. In the work reported here, an innovative analytical method performed by high-performance anion-exchange chromatography (HPAEC) with pulsed electrochemical detection has been optimized and validated for application to the study of prebiotic effects in synbiotic fermented milk prepared by addition of probiotics. The proposed method permits the evaluation of fructooligosaccharides and inulooligosaccharides with degrees of polymerization of 6-7 and 4-7, respectively. Quantitative determination was performed on oligosaccharides, whose standards are not commercially available, by employing calibration curves built by adding a known amount of the fiber used as an ingredient to the matrix. The work provides results from a parallel study on simultaneous variations of prebiotics and probiotics during the shelf life of fermented milk samples. The main advantage over time-consuming, classic enzymatic methods, whose results are limited only to average fiber content, is the possibility of dosing each carbohydrate by performing a single HPAEC run. Validation in terms of detection and quantitation limits, linearity, precision, and recovery was carried out