Liquid oxygen/liquid hydrogen boost/vane pump for the advanced orbit transfer vehicles auxiliary propulsion system

A rotating, positive displacement vane pump with an integral boost stage was designed to pump saturated liquid oxygen and liquid hydrogen for auxiliary propulsion system of orbit transfer vehicle. This unit is designed to ingest 10% vapor by volume, contamination free liquid oxygen and liquid hydrogen. The final pump configuration and the predicted performance are included

Newly formed cystic lesions for the development of pneumomediastinum in Pneumocystis jirovecii pneumonia

<p>Abstract</p> <p>Background</p> <p><it>Pneumocystis jirovecii</it>, formerly named <it>Pneumocystis carinii</it>, is one of the most common opportunistic infections in human immunodeficiency virus (HIV)-infected patients.</p> <p>Case presentations</p> <p>We encountered two cases of spontaneous pneumomediastinum with subcutaneous emphysema in HIV-infected patients being treated for <it>Pneumocystis jirovecii </it>pneumonia with trimethoprim/sulfamethoxazole.</p> <p>Conclusion</p> <p>Clinicians should be aware that cystic lesions and bronchiectasis can develop in spite of trimethoprim/sulfamethoxazole treatment for <it>P. jirovecii </it>pneumonia. The newly formed bronchiectasis and cyst formation that were noted in follow up high resolution computed tomography (HRCT) but were not visible on HRCT at admission could be risk factors for the development of pneumothorax or pneumomediastinum with subcutaneous emphysema in HIV-patients.</p

Strain relief via island ramification in submonolayer heteroepitaxy

The mechanisms of strain relief in submonolayer heteroepitaxy of Cu/Ni(100) are studied using variable temperature scanning tunneling microscopy and high resolution low energy electron diffraction. It is demonstrated that pseudomorphic copper islands, as they grow in size, undergo a spontaneous shape transition. Below a critical island size of about 500 atoms the islands have a compact shape, while above this size they become ramified. The shape transition of the coherently strained islands, predicted theoretically by Tersoff and Tromp, is driven by the size-dependent outward relaxation of the step edge atoms due to the positive lattice mismatch. The ramified island shape, which reflects the energy minimum of binding and strain energy, is characterized by only one parameter: the arm width of the monolayer-high copper islands w = (22 +/- 1) atoms

Studies on transparent spinel magnesium indium oxide thin films prepared by chemical spray pyrolysis

Ternary semiconducting oxide compound magnesium indium oxide films (MgIn2O4), manifesting high transparency were prepared by metal organic chemical spray pyrolysis technique. Precursors prepared for various cationic ratios of Mg/In=0.35, 0.40, 0.45 and 0.50 were thermally sprayed onto quartz substrates, decomposed at 450 °C and the spinel phase evolution was studied. X-ray diffraction, Rutherford backscattering and X-ray photoelectron spectroscopy studies have been conducted to confirm the formation of single-phase MgIn2O4 films with Mg/In ratio 0.50. From optical transmission studies, the observed optical band gaps varied from 3.18 to 3.86 eV (0.35bMg/Inb0.5). The electrical conductivity variations of these films were measured in the temperature range between 30 and 150 °C by four-probe technique (34.07–1.44×10−5 S cm−1) and the Hall coefficient showed n-type electrical conduction and high carrier concentration (0.16×1020–0.89×17 cm−3)