Inhibited solid propellant composition containing beryllium hydride

An object of this invention is to provide a composition of beryllium hydride and carboxy-terminated polybutadiene which is stable. Another object of this invention is to provide a method for inhibiting the reactivity of beryllium hydride toward carboxy-terminated polybutadiene. It was found that a small amount of lecithin inhibits the reaction of beryllium hydride with the acid groups in carboxy terminated polybutadiene

Suppressants for lowering propellant binder burning rate

Addition of boron compound to lower burning rate of solid propellant binder is reported. Chemical reactions involved in propellant binder modification are described. Advantages of method for lowering burning rate are analyzed

Preliminary investigation of the electrodynamics of a conducting tether

An introductory study of the properties of an electrically conducting tether flown from the shuttle is presented. Only a single configuration is considered: a vertical conductor moving normally across the Earth's field, connecting the shuttle to a large conducting balloon that passively extracts electrons from the ionosphere. The distortions in the plasma at maximum current collection are described, as are the local and distant wakes. Numerical values are given

Foreign direct investment and the SME sector

Purpose: Although foreign direct investment (FDI) and entrepreneurship are potential routes to recovery (Girma and Wakelin, 2001; Lyon et al., 2002), existing literature is divided on the relationship between the two. This study examines the influence of foreign investment on the local SME sector after the 2008 financial crisis. Design/methodology/approach: Local authority district data from Great Britain is used to examine the influence of foreign firm employment on the size of the local SME sector as a proportion of all firms, and foreign firm influence on firm births in the locality. In order to control for local geographical, infrastructural, and economic conditions regression analysis is used to examine the relationship between foreign business employment and indigenous business activities. Findings: The potential for technological spillovers and spinout activities appears to dominate with firm birth rates higher where there is greater foreign firm employment. However, there is also evidence of crowding out in relation to the existing SME sector, which is found to be reduced in size where foreign influence through employment is greater. Research Implications: The results here indicating a complementarity relationship between foreign influence on employment and firm births is important for policy makers looking to revive struggling local economies. However, the relevant support needs to be in place to maximise the benefit from the supply of new entrepreneurs generated. Originality/value: Unlike many other studies the relationship between the SME sector, firm births and foreign influence is considered at a local level and where economic conditions are more uncertain and economic recovery is less taken for granted. A better understanding of the relationship allows more appropriate policy to be developed in order to aid local economies to recover

Goldstone radar observations of Mars: The 1986 opposition

Radar echoes from the planet Mars were obtained on 27 S-band (wavelength = 12.5 cm) and 2 X-band (wavelength = 3.5 cm) tracks using the Goldstone Solar System Radar. These observations took advantage of the favorable 1986 opposition since the Earth-Mars distance was 0.40 AU at opposition and radar echo strength is proportional to inverse-fourth-power of the distance to the target. The coverages of the Goldstone observations are summarized. The observations were conducted via the CW-spectra techniques described by Harmon et al. A continuous tone was transmitted at Mars and the radar echo was sampled to obtain a Doppler spread spectrum. Each received event was separated into polarized (opposite sense circular) and depolarized (same sense circular) periods. There was one successful ranging run which had a resolution of 2 microseconds. This should yield surface heights accurate to 300 meters

Breadboard development of a fluid infusion system

A functional breadboard of a zero gravity Intravenous Infusion System (IVI) is presented. Major components described are: (1) infusate pack pressurizers; (2) pump module; (3) infusion set; and (4) electronic control package. The IVI breadboard was designed to demonstrate the feasibility of using the parallel solenoid pump and spring powered infusate source pressurizers for the emergency infusion of various liquids in a zero gravity environment. The IVI was tested for flow rate and sensitivity to back pressure at the needle. Results are presented

High resolution radar map of the Moon

Previous radar mappings of the Moon at 70 cm wavelength in the late 1960's by Thompson have been replaced with a new set of observations using the 430 MHz radar at the Arecibo Observatory, Puerto Rico. Radar resolution was reduced to 2 to 5 km radar cell size and a beam-sweep, limb-to-limb calibration was conducted. Advances in computer technology provided the principle means of improving lunar radar mapping at this wavelength. Observation techniques and data processing are described and scattering differences found in the orthographic projection of the radar data are discussed

Vibration exciting mechanisms induced by flow in turbomachine stages

The quasisteady computer analysis of the perturbated centrifugal impeller passage flow was reviewed. A total of 115 stage calculations were used to define the fluid damping coefficient, delta sub fluid. Results indicate that the average total damping coefficient per stage needed for stability is delta sub total 1.85

Turbulent transport in the solar nebula

It is likely that turbulence played a major role in the evolution of the solar nebula, which is the flattened disk of dust and gas out of which our solar system formed. Relevant turbulent processes include the transport of angular momentum, mass, and heat, which were critically important to the formation of the solar system. This research will break ground in the modeling of compressible turbulence and its effects on the evolution of the solar nebula. The computational techniques which were developed should be of interest to researchers studying other astrophysical disk systems (e.g., active galactic nuclei), as well as turbulence modelers outside the astrophysics community