Shear coaxial injectors are a common injector type for liquid-rocket-propulsion applications and can be found in many oxygen/hydrogen engines. These injectors rely on the shear between an outer lower-density, high-velocity annulus and a higher-density, low-velocity inner jet to atomize and mix the propellants. Because of the dense-jet core, the optical densities of these sprays are high, partic...

Langmuir probe, optical emission spectroscopy, and biased quartz crystal microbalance measurements were used to investigate an argon and copper plasma used for ionized physical vapor deposition of copper. Copper vapor generated by a magnetron sputter discharge is ionized upon passing through an argon discharge excited by an internal rf induction antenna. Argon plasma characteristics such as ele...

We compare the H I column densities from Lyα absorption to the metal column densities from X-ray absorption in γ-ray burst (GRB) afterglows. Eight bursts of seventeen entering the sample, have significant extragalactic X-ray absorptions. Of these we find a range in metallicities from sub-solar to a few hundred times the solar value. There is a complete lack of correlation between the X-ray and ...

We present far-UV and UV spectroscopic observations of Proxima Centauri obtained as part of our continued investigation into the optically thin approximation assumed for the transition regions of late-type stars. Significant opacity is found in the C iii lines during both the quiescent and flaring states of Proxima Cen, with up to 70% of the expected flux being lost in the latter. Our findings ...

This study reports an application of instrumental color measurement for quantifying and comparing the optical properties of high density polyethylene HDPE and low density polyethylene LDPE blend films and the effect of blending ratio and miscibility on these properties. The technique of spectrophotometry in transmission and reflectance modes can be used as a versatile tool to evaluate the color...

In this article, ZnO and ZnO:Mn nanoparticles prepared by reverse micelle method. The various crystalline properties of these nanoparticles such as size, d-spacing, strain, stress, dislocation density and texture coefficient have been calculated with the help of XRD spectrum. The XRD results indicated that the synthesized ZnO and ZnO:Mn nanoparticles have a pure wurtzite (hexagonal phase) struc...

A new strategy for enhancing the efficiency of TiO2 dye-sensitized solar cells (DSSCs) by doping foreign ion into TiO2 lattice via sol-gel process is reported. DSSCs are based on a semiconductor (i.e., TiO2), formed between a photo-sensitized anode and an electrolyte. In order to reach high conversion efficiency, it is important to increase the electron injection and optical absorption. One pro...