Dense W and W-Zr composites reinforced with Sc2O3 particles were produced through powder metallurgy and subsequent spark plasma sintering (SPS) at 1700 °C and 58 MPa. Results showed that the W-1vol.%Zr/2vol.%Sc2O3 composites exhibited optimal performance with the best relative density of up to 98.93% and high Vickers microhardness of approximately 583 Hv. The thermal conductivity of W-Zr/Sc2O3 ...

Despite SiGe being one of the most widely studied thermoelectric materials owing to its application in radioisotope thermoelectric generators (RTG), the thermoelectric figure-of merit (ZT) of p-type SiGe is still quite low, resulting in poor device efficiencies. In the present study, we report a substantial enhancement in ZT∼ 1.2 at 900 °C for p-type nanostructured Si80Ge20 alloys by creating s...

Ca(+) sparks are vascular smooth muscle cell (VSMC) Ca(2+)-release events that are mediated by ryanodine receptors (RyR) and promote vasodilation by activating large-conductance Ca(2+)-activated potassium channels and inhibiting myogenic tone. We have previously reported that exposing rats to intermittent hypoxia (IH) to simulate sleep apnea augments myogenic tone in mesenteric arteries through...

The concept of minimum ignition energy (MIE) has traditionally formed the basis for studying ignition hazards of fuels. However, the viewpoint of ignition as a statistical phenomenon appears to be more consistent with the inherent variability in engineering test data. We have developed a very low-energy capacitive spark ignition system to produce short sparks with fixed lengths of 1 to 2 mm, an...

Cu–Al bronzes are interesting metallic materials, demonstrating higher hardness, wear resistance, corrosion resistance and a lower friction coefficient as compared with unalloyed copper. The powder metallurgy approach to the fabrication of these alloys presents opportunities tailor their phase composition grain size. In present work, structural characteristics, properties Cu-10 wt.% Al obtained...

The article presents a method of mathematical correction to be applied the results measuring intensity spectral lines using charge-coupled devices (CCDs) in presence blooming effect. This technique is particularly applicable atomic emission spectroscopy. It enables expansion dynamic range spark spectrometers and significantly minimizes result distortions measurements taken area high element con...

In this work, Al-20Si-10Fe-6Cr and Al-20Si-10Fe-6Mn (wt %) alloys were prepared by a combination of short-term mechanical alloying and spark plasma sintering. The microstructure was composed of homogeneously dispersed intermetallic particles forming composite-like structures. X-ray diffraction analysis and TEM + EDS analysis determined that the α-Al along with α-Al15(Fe,Cr)₃Si₂ or α-Al15(Fe,Mn)...

the molybdenum dicilicide is an intermetallic compound with two allotropies tetragonal ?-mosi2 and hexagonal ?-mosi2.the ?-mosi2 phase is established to 1900 ?c and ?-mosi2 phase from 1900 to 2050 ?c. this material has considerable properties that provide different applications in different industries such as air-space industry and gas turbines. the molybdenum synthesis can be down in various w...

A survey of the development of the spark chamber from the spark counter is given. An effort has been made to clarify the early history of the device. Some unpublished recent Russian work on spark chambers is summarized. A consistent terminology for the various times relevant to spark chamber operation is suggested.

Almost perfect embedding of SnO2 nanocrystallites in carbon nanopores was achieved by in situ synthesis using vaporized SnCl2 and silica opal-derived nanoporous carbons. The reversibility of SnO2-Sn conversion and Sn-Li alloying/de-alloying reactions was greatly enhanced by the confinement in regulated carbon nanospace.