Completely modular Thermionic Reactor Ion Propulsion System (TRIPS)

The nuclear reactor powered ion propulsion system described is an advanced completely modularized system which lends itself to development of prototype and/or flight type components without the need for complete system tests until late in the development program. This modularity is achieved in all of the subsystems and components of the electric propulsion system including (1) the thermionic fuel elements, (2) the heat rejection subsystem (heat pipes), (3) the power conditioning modules, and (4) the ion thrusters. Both flashlight and external fuel type in-core thermionic reactors are considered as the power source. The thermionic fuel elements would be useful over a range of reactor power levels. Electrical heated acceptance testing in their flight configuration is possible for the external fuel case. Nuclear heated testing by sampling methods could be used for acceptance testing of flashlight fuel elements. The use of heat pipes for cooling the collectors and as a means of heat transport to the radiator allows early prototype or flight configuration testing of a small module of the heat rejection subsystem as opposed to full scale liquid metal pumps and radiators in a large vacuum chamber. The power conditioner (p/c) is arranged in modules with passive cooling

Stability and control characteristics of a monoplanar elliptic missile model at Mach numbers from 1.60 to 2.86

An investigation was conducted of a monoplanar maneuverable missile concept having a nose forebody with a circular cross section and a centerbody and afterbody with elliptical cross sections. The tests involved several component changes and were conducted in the low Mach number test section of the Langley Unitary Plan wind tunnel at Mach numbers of 1.60, 2.16, and 2.86, at angles of attack ranging from -4 degs to 28 degs and at sideslip angles ranging from -4 degs to 8 degs. The most significant result was that at the highest Mach number (2.86), the configuration with the infrared nose produced nearly twice the axial force as the same configuration with the radar nose. The cranked wing had a destabilizing effect on the longitudinal stability and had no effect on the lateral-directional stability. The nose strakes had no effect longitudinally and were detrimental to the lateral-directional stability

Evaluation of the Illinois Soil Nitrogen Test in the North Central Region

Data from 96 locations across the North Central Region was complied to evaluate the usefulness of the Illinois soil nitrogen test (ISNT) in identifying fields where corn will not respond to additional N fertilizer and predicting the yield optimizing N rate (YONR) for each field. The ISNT could not accurately predict non-responsive sites, nor could it predict YONR. Sub-setting the data based on soil drainage class and previous crop did not improve the predictive capability of the ISNT. The ISNT was related to soil organic matter and was measuring a constant fraction of total soil N. The ISNT is not a meaningful tool upon which N rate decisions should be based

An Appraisal of the Potential for Soybeans in the United Kingdom

Soybean is a most important crop worldwide, accounting for 56% of world oilseed production and 69% of world protein meal consumption in 2003 (Soystats, 2004). Since their introduction in the early 1800\u27s, forage soybeans have been grown widely in USA. Used originally as a forage crop, this use largely had been forgotten until Dr T. E. Devine (United States Department of Agriculture, Agricultural Research Service; USDA-ARS) released 4 new forage cultivars. Soybeans potentially offer UK farmers a high quality protein source in a short season and also meet the requirements of supermarket chains to remain GM free. This paper aims to indicate whether soybeans can be grown successfully in the UK