Marine microorganisms have unique physiological properties and novel metabolites such as biosurfactant to live in extreme habitats (e.g. oil polluted environment). The aim of this study was to characterize some biosurfactant-producing bacteria collected from sediment and seawater samples from the Caspian Sea. These bacteria were isolated using enrichment method in ONR7a medium with crude oil as...

This study focuses on the impact of solidification inclusion morphologies in different sizes production-scale electro-slag remelting (ESR) and under a protected pressure-controlled atmosphere, (PESR), ingots, common martensitic stainless steel grade. The investigation has been carried out to increase knowledge change during ESR PESR remelting. In order optimize process routes for grades, it is ...

Abstract This study analysed the influence of codeposition SiC particles with different sizes: 50 nm, 500 nm and 5 μm, type bath agitation (stirring or ultrasonic) on electrocrystallisation nickel coatings. The composites matrix microstructure was by means SEM, EBSD XRD, to evaluate grain size, crystal orientation, internal stresses benchmarked against pure samples electrodeposited in equivalen...

Qualitative EDX analysis: A map is acquired in low magnification. Results show equiaxial grains finely distributed through out the sample. In spite of the fact that simulations indicate no clear energetic gain or loss for cosegreation over single dopant segregation in this material, we observed that in all grain boundaries these two dopants (Y an La) are segregating together (figure 2). This co...

background and objective: molecular epidemiological studies have shown that certain genotypes of mycobacterium tuberculosis (mtb) are over-represented in limited geographical regions, suggesting of evolution of certain genotypes with increasing virulence and pathogenicity. beijing strain of mtb was initially described by its potential to cause outbreaks worldwide and its association with drug r...

The effect of particle size and sintering temperature the mixtures kyanite metallic aluminum related to thermal transformation into primary mullite free silica was studied. In addition, reaction between ?-Al2O3 (in situ produced by oxidation) obtained in cristobalite structure from obtain secondary mullite. powders were milled 0.5, 3, 6, 12 hours then mixed with powder, which previously 3 hours...

The failure of a chromium plating layer on the surface piston rod was analyzed, and an Ni-based alloy mixed with niobium (Nb) composite coating investigated by means stereomicroscopy, metallographic microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), Vickers hardness testing, wear testing. results show that penetrating cracks were prese...

In this paper, low cycle fatigue life of CK45 steel and SS316 stainless steel under strain-controlled loading are experimentally investigated. In addition, the impact of mean strain and strain amplitude on the fatigue life and cyclic behavior of the materials are studied. Furthermore, it is attempted to predict fatigue life using energy and SWT damage parameters. The experimental results demons...