Asatov, U T
In the present work the characteristics of backward (90 sup d eg
The design, development, fabrication and testing of a shingle-type terrestrial solar cell module which produces 98 watts/m/sup 2/ of exposed module area at 1 kW/m/sup 2/ insolation and 61/sup 0/C are reported. These modules make it possible to easily incorporate photovoltaic power generation into the sloping roofs of residential or commercial buildings by simply nailing the modules to the plywood roof sheathing. This design consists of nineteen series-connected 53 mm diameter solar cells arranged in a closely packaged hexagon configuration. These cells are individually bonded to the embossed surface of a 3 mm thick thermally tempered hexagon-shaped piece of ASG SUNADEX glass. Monsanto SAFLEX polyvinyl butyral is used as the laminating adhesive. RTVII functions as the encapsulant between the underside of the glass superstrate and a rear protective sheet of 0.8 mm thick TEXTOLITE. The semi-flexible portion of each shingle module is a composite laminate construction consisting of outer layers of B.F. Goodrich FLEXSEAL and an epichlorohydrin closed cell foam core. The module design has satisfactorily survived the JPL-defined qualification testing program which includes 50 thermal cycles between -40 and +90/sup 0/C, a seven-day temperature-humidity exposure test and a mechanical integrity test consisting of a bidirectional cyclic loading at 2390 Pa (50 lb/ft/sup 2/) which is intended to simulate loads due to a 45 m/s (100 mph) wind.
de la Torre, Rosa; Sancho, Leopoldo G.; Horneck, Gerda; Ríos, Asunción de los; Wierzchos, Jacek; Olsson-Francis, Karen; Cockell, Charles S.; Rettberg, Petra; Berger, Thomas; de Vera, Jean-Pierre P.; Ott, Sieglinde; Frías, Jesus Martinez; Melendi, Pablo Gonzalez; Lucas, Maria Mercedes; Reina, Manuel; Pintado, Ana; Demets, René
In the space experiments Lithopanspermia, experimental support was provided to the likelihood of the lithopanspermia concept that considers a viable transport of microorganisms between the terrestrial planets by means of meteorites. The rock colonising lichens Rhizocarpon geographicum and Xanthoria elegans, the vagrant lichen Aspicilia fruticulosa, and endolithic and endoevaporitic communities of cyanobacteria and bacteria with their natural rock substrate were exposed to space for 10 days onboard the Biopan facility of the European Space Agency (ESA). Biopan was closed during launch and re-entry. In addition, in the Stone facility, one sample of R. geographicum on its natural granitic substrate was attached at the outer surface of the re-entry capsule close to the stagnation point, only protected by a thin cover of glass textolite. Post-flight analysis, which included determination of the photosynthetic activity, LIVE/DEAD staining, and germination capacity of the ascospores, demonstrated that all three lichen were quite resistant to outer space conditions, which include the full spectrum of solar extraterrestrial electromagnetic radiation or selected wavelength ranges. This high resistance of the lichens to space appears to be due to their symbiotic nature and protection by their upper pigmented layer, the cortex. In contrast, the rock- or halite-inhabiting bacteria were severely damaged by the same exposure. After atmospheric re-entry, the granite of the Stone sample was transformed into a glassy, nearly homogenous material, with several friction striae. None of the lichen cells survived this re-entry process. The data suggest that lichens are suitable candidates for testing the concept of lithopanspermia, because they are extremely resistant to the harsh environment of outer space. The more critical event is the atmospheric re-entry after being captured by a planet. Experiments simulating the re-entry process of a microbe-carrying meteoroid did not show any
Г. В. Камарчук
Full Text Available Background: The problem of detecting the different strains of H. pylori has gained great importance today due to the worldwide prevalence of this bacterium and its role in the pathogenesis of a number of serious gastric and extragastric diseases. However, not all H. pylori strains are aggressive and require antibiotic treatment. Thus, the question arises about the necessity of differentiating these bacterium strains with respect to their virulence factors. In accordance with the IV Maastricht Consensus Report, among the variety of ways to diagnose H. pylori infection, non-invasive methods should be given preference. Most of them are based on the analysis of gas which is exhaled by a human. Mass spectrometry, gas chromatography, and IR spectroscopy are currently the mostly used ones. However, despite the obvious advantages, these techniques have a number of disadvantages that make them difficult to use in everyday medical practice. Modern sensor devices can become an inexpensive and easy to access alternative to these technologies. Objectives: The aim of the work is to develop a new type of sensor device for selective recognition of H. pylori strains which is based on analysis of a mixture of gases exhaled by human. Such a kind of device can be designed on the basis of a point-contact gas sensor. Materials and methods: Anion-radical salts of the organic conductor TCNQ were chosen as the sensitive material for point-contact sensors. The fundamental properties of point contacts which are used in the Yanson point-contact spectroscopy make it possible to create a point-contact mesoscopic matrix on the basis of this material, which is sensitive to small concentrations of components in complex gas media. The sensors were obtained by electrochemical deposition of salts from a solvent characterized by a high vapor pressure on a textolite substrate. Gas exhaled by a human served as the substance to be analyzed. The measurements were carried out following