We present a quantitative evaluation of the influence of the electron transfer on the magnetic properties of mixed-valence polyoxometalates reduced by two electrons. For that purpose, we extract from valence-spectroscopy ab initio calculations on embedded fragments the value of the transfer integrals between W nearest-neighbor atoms in a mixed-valence alphaPW(12)O(40) polyoxowolframate Keggin a...

Effect of addition of filler material to the natural fiber composite was experimentally investigated. Composites are manufactured by the conventional hand-layup method. All composites are made with a fixed banana fiber with 15% weight fraction addition of different weight fraction of (0, 3, 5, 7.5%) groundnut shell ash is added to the composite. Tensile, hardness, impact and compressive strengt...

the organo-metal salt of aluminum triacrylate (alta) with a general formula of (ch2=chcoo)3al was  synthesized  as  a  reactive  fller  for  elastomers through a two-step synthetic procedure. fourier transform-infrared spectroscopy (ftir), dsc and dta were employed for alta analysis and to study its cure characteristics. in this research, two composites based on ethylene propylene diene monomer...

In this study, polyaniline-graphene composites with different nano-structures are synthesized and the behaviour of the obtained composites serving as electrode materials in electrochemical capacitors is studied. The morphology, crystal structure, and thermal stability of the composites are examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Thermal gravimetric analys...

nasoohi n 1 hoorizad m1 torabzadeh tari n 2   1- assistant prof, department of operative dentistry, islamic azad university, dental branch, tehran,iran   2-dentist   corresponding author : nasoohi n: department, no 4, 10th neyestan ave, pasdaran, tehran   tel : 09125392175 email: [email protected]     background and aim: discoloration of dental composites is one of the major reasons of the...

Metal matrix composite (MMC) is engineered combination of the metal (matrix) and hard particle (reinforcement) to get tailored properties. MMCs are either in use or prototyping for the space shuttle, commercial airliners, electronic substrates, automobiles, golf clubs, and a variety of other applications.In this study, carbon nanotubes (CNTs) reinforced aluminum MMCs were synthesized by DPDS fo...

The use of agriculture residues as filler in composites is increasing due to their strength, abundance and low cost. Soya stalks show promising renewable natural fiber. In polyethylene composites the physical and mechanical properties (flexural resistance, tensile, impacted absorbed energy, water uptake and thickness swelling) was examined at different composites. The results showed that, the m...

in this research, effects of concentration and time of silane treatment of rice straw flour on the morphology and mechanical strengths of rice straw flour/polypropylene composites were investigated. tri ethoxy vinyl silane (c8h18o3si) with 98% purity in two concentrations of 5 and 10%, that each concentration had two immersion times including, 45 and 90 min for using treatment rice straw flour....

Co-Continuous Ceramic Composites, referred to as C4, have bi-continuous, interconnected and interpenetrating phases of a metal and ceramic. This bestows such composites with a higher strength to weight ratio compared with traditional composites. In this research work, a C4 composite of AA5083/SiC is fabricated for personal body armour, using gravity infiltration technique. A numerical simulatio...

industrial production of thermoset composite components involves the application of a vacuum bagging and autoclave pressure to minimize void percentage, usually to less than 5%. phenolic resin systems generate water as a reaction byproduct via condensation reactions during curing at elevated temperatures. in this paper, vacuum bagging and simple manufactured autoclave curing systems are used fo...