High strain rate behavior of aluminum die cast components

Abstract Research results of static and dynamic mechanical tests (ɛ = 1 * 10-3 s-1 and ɛ ~ 5 * 102 s-1 conducted on samples obtained from three different die cast products (component A, B and C) of AlSi10MnMg alloy are reported. All the components have thin-walled geometry except some thicker positions of component C. The dynamic (high strain rate) mechanical characterization shows an increase of tensile properties, in respect to static tensile ones (tensile strength increases approximately 15%, and the yield strength 30%, for all the die cast components) together with an evident plastic deformation, with consequent necked region in the fractured section, substantially negligible in case of static tensile tests. Moreover, fractographic observations are conducted on specimens undergone static and high strain rate test conditions, to observe the fracture morphology, together with metallographic analysis on the only polished or etched transverse specimens to reveal the porosity, and the microstructure of dendrite and inter-dendrite morphologies

Metal-based compounds containing selenium: An appealing approach towards novel therapeutic drugs with anticancer and antimicrobial effects

In recent years, both metal-based complexes and selenium-containing compounds have been widely explored for their therapeutic properties due to their roles in biological processes and modulation of diverse molecular tar- gets. However, despite their growing interest, there is no review to date that covers the potential use of the combination of these entities to design new therapeutic derivatives. This review highlights the latest achieve- ments in this particular field, with a focus on compounds with anticancer and/or antimicrobial properties. With this aim, the formation of coordination compounds including several metals bearing selenium either with direct interaction with the metal center or as part of the organic ligand elsewhere is covered. Besides, coordination compounds with a Se(IV) center have been assessed. The biological properties of several selenium-containing organometallic complexes have also been discussed, including metallocenes, half-sandwich complexes, and compounds with N-heterocyclic carbenes, CO, and π-ligands, and other σ-bonded entities. The information compiled in this review may be helpful to design and develop novel, more potent, and safer metal-based com- pounds for the treatment of several pathologies

Ethyl 2-phenyl-3-(4-phenyl-1,2,3-selenadiazol-5-yl)-3-p-tolyl­propano­ate

In the title compound, C26H24N2O2Se, the selenadiazole ring is essentially planar [maximum deviation = 0.004 (3) Å]. The dihedral angle between the selenadiazole ring and the attached benzene ring is 50.17 (1)°. The crystal packing is stabilized by inter­molecular C—H⋯N inter­actions

M13 phages uptake of gold nanoparticles for radio-and thermal-therapy and contrast imaging improvement

The presented work deals with the uptake of gold nanoparticles (Au NPs) by M13 phages in solutions. In particular, the Au NPs uptake modalities and their localization in the filamentous phages are evaluated and measured. Gold spherical nanoparticles (with an average diameter of the order of 10 nm) are obtained by laser ablation in water with a sodium citrated surfactant. The interest of such application comes from the possibility to employ living biological structures to transport heavy metallic nanoparticles inside cells of tumoral tissues. Indeed, phages have the capability to introduce Au NPs in the proximity to the cell nucleus, increasing the efficiency of DNA destruction in the tumoral cells by employing low doses of ionizing radiation during radiotherapy and hyperthermia treatments. Several analyses and microscopy characterizations of the prepared phages samples embedding gold nanoparticles are presented, demonstrating that the presence of Au NPs increases the phages imaging contrast

PECVD Coatings for Magnesium Casting Protection

In this study SiO2-like films have been deposited by Plasma Enhanced Chemical Vapour Deposition(PECVD) on Mg alloys employed in the automotive industry in different experimental conditions in orderto optimize the protective effectiveness of the deposited layers. The experimental apparatus used was acapacitive coupled (CC) parallel-plate-reactor with an asymmetric electrode configuration, theelectromagnetic radiation was applied to a gas mixture containing tetraetoxysilane (TEOS), oxygen andargon in different ratios. The deposition was performed at 100 mTorr of pressure, by varying the inputpower, on as cast and polished samples submitted to a pre-treatment step in H2-containing plasma. A setof Mg alloy specimens has been treated with a standard anodising process (AP).From the overall experimental results, PECVD appears an attractive surface modification techniquewhich allows, through the deposition of SiO2-like films, to increase the corrosion resistance of Mg alloys,usually protected with anodising treatment or with chromium-based coatings. The check of thetransferability of deposition process to a medium scale range is now running. Magnesium framesrepresentative of real automotive parts coated in a PECVD industrial chamber, assembled and paintedare submitted to accelerated corrosion test in order to verify the corrosion resistance of these paintedelements manufactured following the production steps of a real component

Effects of pesticides on Chelon labrosus (Risso, 1827) evaluated by enzymatic activities along the north eastern Sicilian coastlines (Italy)

Pesticides are frequently applied to agricultural activities to improve harvest, in terms of yield and product quality. Useful tools for ecotoxicological studies of marine ecosystems are based on biomarker application on bioindicator key fish species. The main aim of the present study was to detect the potential presence of pesticides in a polluted coastal marine environment, namely Milazzo Gulf, situated in the north eastern coast of Sicily (Italy), by measuring the enzymatic activities of the ecotoxicological biomarkers acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in brain and blood samples of Chelon labrosus. Also, Marinello Reserve was selected as a reference site. The data showed a significant inhibition in AChE (81%) and BChE (71%) activities in fish from Milazzo Gulf in respect to those from the reference site. The esterase inhibition is primarily due to the presence of organophosphorus insecticides and carbamates that resulted, in Milazzo Gulf, higher in concentration in respect to the reference quality standard decree (D.M. 260, 2010). The results obtained in this study confirm the suspected presence of insecticides in waters and fish from Milazzo Gulf, which may lead to a considerable hazard to humans. This study confirms the relevant advantages of the biomarker approach on fish species in the ecotoxicological evaluation of marine environments

Design, synthesis and anticancer evaluation of novel Se-NSAID hybrid molecules: Identification of a Se-indomethacin analog as a potential therapeutic for breast cancer

A total of twenty-five novel carboxylic acid, methylester, methylamide or cyano nonsteroidal anti-inflammatory drug (NSAID) derivatives incorporating Se in the chemical form of selenoester were reported. Twenty Se-NSAID analogs exhibited an increase in cytotoxic potency compared with parent NSAID scaffolds (aspirin, salicylic acid, naproxen, indomethacin and ketoprofen). Top five analogs were selected to further study their cytotoxicity in a larger panel of cancer cells and were also submitted to the DTP program of the NCI’s panel of 60 cancer cell lines. Compounds 4a and 4d stood out with IC50 values below 10 μM in several cancer cells along with a selectivity index higher than 5 in breast cancer cells. Remarkably, analog 4d was found to inhibit cell growth notably in two breast cancer cell lines by inducing apoptosis, and to be metabolized to release the parent NSAID along with the Se fragment. Taken together, our results show that Se-NSAID analog 4d could be a potential chemotherapeutic drug for breast cancer